Novel Method of Aluminum to Copper Bonding by Cold Spray

NASA Astrophysics Data System (ADS)

Fu, Si-Lin; Li, Cheng-Xin; Wei, Ying-Kang; Luo, Xiao-Tao; Yang, Guan-Jun; Li, Chang-Jiu; Li, Jing-Long

2018-04-01

Cold spray bonding (CSB) has been proposed as a new method for joining aluminum and copper. At high speeds, solid Al particles impacted the groove between the two substrates to form a bond between Al and Cu. Compared to traditional welding technologies, CSB does not form distinct intermetallic compounds. Large stainless steel particles were introduced into the spray powders as in situ shot peen particles to create a dense Al deposit and to improve the bond strength of joints. It was discovered that introducing shot peen particles significantly improved the flattening ratio of the deposited Al particles. Increasing the proportion of shot peen particles from 0 to 70 vol.% decreased the porosity of the deposits from 12.4 to 0.2%, while the shear strength of joints significantly increased. The tensile test results of the Al-Cu joints demonstrated that cracks were initiated at the interface between the Al and the deposit. The average tensile strength was 71.4 MPa and could reach 81% of the tensile strength of pure Al.

Femtosecond laser etching of dental enamel for bracket bonding.

PubMed

Kabas, Ayse Sena; Ersoy, Tansu; Gülsoy, Murat; Akturk, Selcuk

2013-09-01

The aim is to investigate femtosecond laser ablation as an alternative method for enamel etching used before bonding orthodontic brackets. A focused laser beam is scanned over enamel within the area of bonding in a saw tooth pattern with a varying number of lines. After patterning, ceramic brackets are bonded and bonding quality of the proposed technique is measured by a universal testing machine. The results are compared to the conventional acid etching method. Results show that bonding strength is a function of laser average power and the density of the ablated lines. Intrapulpal temperature changes are also recorded and observed minimal effects are observed. Enamel surface of the samples is investigated microscopically and no signs of damage or cracking are observed. In conclusion, femtosecond laser exposure on enamel surface yields controllable patterns that provide efficient bonding strength with less removal of dental tissue than conventional acid-etching technique.

Effect of Bonding Agent Application Method on Titanium-Ceramic Bond Strength.

PubMed

Curtis, Joseph G; Dossett, Jon; Prihoda, Thomas J; Teixeira, Erica C

2015-07-01

Although milled titanium may be used as a substructure in fixed and implant prosthodontics, the application of the veneering porcelain presents particular challenges compared to traditional alloys. To address these challenges, some Ti ceramic systems incorporate the application of a bonding agent prior to the opaque layer. Vita Titankeramik's bonding agent is available as a powder, paste, and spray-on formulation. We examined the effect of these three application methods on the bond strength. Four titanium bars were milled from each of 11 wafers cut from grade II Ti using the Kavo Everest milling unit and a custom-designed milling toolpath. An experienced technician prepared the 25 × 3 × 0.5 mm(3) metal bars and applied bonding agent using one of three application methods, and then applied opaque, dentin, and enamel porcelains according to manufacturer's instructions to a 8 × 3 × 1 mm(3) porcelain. A control group received no bonding agent prior to porcelain application. The four groups (n = 11) were blindly tested for differences in bond strength using a universal testing machine in a three-point bend test configuration, based on ISO 9693-1:2012. The average (SD) bond strengths for the control, powder, paste, and spray-on groups, respectively, were: 24.8 (2.6), 24.6 (2.6), 25.3 (4.0), and 24.1 (3.9) MPa. One-way ANOVA and Tukey's multiple comparison tests were performed between all groups. There were no statistically significant differences among groups (p = 0.951). Titanium-porcelain bond strength was not affected by the use of a bonding agent or its application method when tested by ISO 9693-1 standard. © 2014 by the American College of Prosthodontists.

Elasticity and Strength of Biomacromolecular Crystals: Lysozyme

NASA Technical Reports Server (NTRS)

Holmes, A. M.; Witherow, W. K.; Chen, L. Q.; Chernov, A. A.

2003-01-01

The static Young modulus, E = 0.1 to 0.5 GPa, the crystal critical strength (sigma(sub c)) and its ratio to E,sigma(sub c)/E is approximately 10(exp 3), were measured for the first time for non cross-linked lysozyme crystals in solution. By using a triple point bending apparatus, we also demonstrated that the crystals were purely elastic. Softness of protein crystals built of hard macromolecules (26 GPa for lysozyme) is explained by the large size of the macromolecules as compared to the range of intermolecular forces and by the weakness of intermolecular bonds as compared to the peptide bond strength. The relatively large reported dynamic elastic moduli (approximately 8 GPa) from resonance light scattering should come from averaging over the moduli of intracrystalline water and intra- and intermolecular bonding.

Friction pull plug welding: chamfered heat sink pull plug design

NASA Technical Reports Server (NTRS)

Coletta, Edmond R. (Inventor); Cantrell, Mark A. (Inventor)

2005-01-01

The average strength of a pull plug weld is increased and weak bonding eliminated by providing a dual included angle at the top one third of the pull plug. Plugs using the included angle of the present invention had consistent high strength, no weak bonds and were substantially defect free. The dual angle of the pull plug body increases the heat and pressure of the weld in the region of the top one third of the plug. This allows the plug to form a tight high quality solid state bond. The dual angle was found to be successful in elimination of defects on both small and large plugs.

Effect of metal surface topography on mechanical bonding at simulated total hip stem-cement interfaces.

PubMed

Chen, C Q; Scott, W; Barker, T M

1999-01-01

Bonding and loosening mechanisms between bone cement and joint prostheses have not been well identified. In this study, the effects of simulated hip stem surface topography on the interfacial shear strength were examined. Six different surface topographies were used. They were described by several surface characterization parameters that may directly relate to the interfacial bonding strength: average surface roughness R(a), root mean square slope R(Deltaq), correlation length beta, and fluid retention index R(ri). The shear strengths between Palacos E bone cement and stainless steel rods were measured using an Instron materials testing machine. We found that cement can "flow" into the surface microtopography and establish good contact with the metal surface. The results show that the interfacial strength increases monotonically with the increase of R(Deltaq) instead of with R(a). The relationship between interfacial strength and surface parameters shows that a metal stem with an isotropic surface texture, higher R(Deltaq), and greater R(ri) gives a higher interfacial strength. Copyright 1999 John Wiley & Sons, Inc.

Veneer Ceramic to Y-TZP Bonding: Comparison of Different Surface Treatments.

PubMed

Kirmali, Omer; Kapdan, Alper; Kustarci, Alper; Er, Kursat

2016-06-01

The purpose of this study was to evaluate the effects of various surface-treatment techniques for enhancing the bond strength between veneering ceramic and yttria-stabilized tetragonal zirconia polycrystals (Y-TZP). Pre-sintered Y-TZP specimens were divided into eight groups (n = 10) according to the surface-treatment technique used: (a) untreated (control); (b) air abrasion with aluminum oxide particles; (c) erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser irradiation at different energy intensities (1 to 6 W). All specimens were then sintered and veneered with veneering ceramic according to the manufacturer's instructions. The obtained zirconia-ceramic specimens were immersed in 37°C distilled water for 24 hours before a shear bond strength test using a universal testing device at a 1 mm/min crosshead speed. The average values were calculated. After debonding, the Y-TZP surfaces were examined under a stereomicroscope to determine their fracture pattern, and the surface topography was evaluated with scanning electron microscopy after surface treatments. The bond strength ranged from 13.24 to 20.54 MPa. All surface treatments increased the bond strength between the veneering ceramic and Y-TZP; however, the value for the 6 W irradiation group was significantly different from the values for other groups (p ˂ 0.05). The present study's findings showed that higher energy densities were needed for the laser irradiation to improve the bond strength between the veneering ceramic and zirconia. Y-TZP is commonly used as a core material in fixed restorations. The bond strength between zirconia and the veneering ceramic can be affected by various surface treatments. © 2015 by the American College of Prosthodontists.

Geometry, packing, and evolutionary paths to increased multicellular size

NASA Astrophysics Data System (ADS)

Jacobeen, Shane; Graba, Elyes C.; Brandys, Colin G.; Day, Thomas C.; Ratcliff, William C.; Yunker, Peter J.

2018-05-01

The evolutionary transition to multicellularity transformed life on earth, heralding the evolution of large, complex organisms. Recent experiments demonstrated that laboratory-evolved multicellular "snowflake yeast" readily overcome the physical barriers that limit cluster size by modifying cellular geometry [Jacobeen et al., Nat. Phys. 14, 286 (2018), 10.1038/s41567-017-0002-y]. However, it is unclear why this route to large size is observed, rather than an evolved increase in intercellular bond strength. Here, we use a geometric model of the snowflake yeast growth form to examine the geometric efficiency of increasing size by modifying geometry and bond strength. We find that changing geometry is a far more efficient route to large size than evolving increased intercellular adhesion. In fact, increasing cellular aspect ratio is on average ˜13 times more effective than increasing bond strength at increasing the number of cells in a cluster. Modifying other geometric parameters, such as the geometric arrangement of mother and daughter cells, also had larger effects on cluster size than increasing bond strength. Simulations reveal that as cells reproduce, internal stress in the cluster increases rapidly; thus, increasing bond strength provides diminishing returns in cluster size. Conversely, as cells become more elongated, cellular packing density within the cluster decreases, which substantially decreases the rate of internal stress accumulation. This suggests that geometrically imposed physical constraints may have been a key early selective force guiding the emergence of multicellular complexity.

Grinding damage assessment on four high-strength ceramics.

PubMed

Canneto, Jean-Jacques; Cattani-Lorente, Maria; Durual, Stéphane; Wiskott, Anselm H W; Scherrer, Susanne S

2016-02-01

The purpose of this study was to assess surface and subsurface damage on 4 CAD-CAM high-strength ceramics after grinding with diamond disks of 75 μm, 54 μm and 18 μm and to estimate strength losses based on damage crack sizes. The materials tested were: 3Y-TZP (Lava), dense Al2O3 (In-Ceram AL), alumina glass-infiltrated (In-Ceram ALUMINA) and alumina-zirconia glass-infiltrated (In-Ceram ZIRCONIA). Rectangular specimens with 2 mirror polished orthogonal sides were bonded pairwise together prior to degrading the top polished surface with diamond disks of either 75 μm, 54 μm or 18 μm. The induced chip damage was evaluated on the bonded interface using SEM for chip depth measurements. Fracture mechanics were used to estimate fracture stresses based on average and maximum chip depths considering these as critical flaws subjected to tension and to calculate possible losses in strength compared to manufacturer's data. 3Y-TZP was hardly affected by grinding chip damage viewed on the bonded interface. Average chip depths were of 12.7±5.2 μm when grinding with 75 μm diamond inducing an estimated loss of 12% in strength compared to manufacturer's reported flexural strength values of 1100 MPa. Dense alumina showed elongated chip cracks and was suffering damage of an average chip depth of 48.2±16.3 μm after 75 μm grinding, representing an estimated loss in strength of 49%. Grinding with 54 μm was creating chips of 32.2±9.1 μm in average, representing a loss in strength of 23%. Alumina glass-infiltrated ceramic was exposed to chipping after 75 μm (mean chip size=62.4±19.3 μm) and 54 μm grinding (mean chip size=42.8±16.6 μm), with respectively 38% and 25% estimated loss in strength. Alumina-zirconia glass-infiltrated ceramic was mainly affected by 75 μm grinding damage with a chip average size of 56.8±15.1 μm, representing an estimated loss in strength of 34%. All four ceramics were not exposed to critical chipping at 18 μm diamond grinding. Reshaping a ceramic framework post sintering should be avoided with final diamond grits of 75 μm as a general rule. For alumina and the glass-infiltrated alumina, using a 54 μm diamond still induces chip damage which may affect strength. Removal of such damage from a reshaped framework is mandatory by using sequentially finer diamonds prior to the application of veneering ceramics especially in critical areas such as margins, connectors and inner surfaces. Copyright © 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Influence of Thin-Film Adhesives in Pullout Tests Between Nickel-Titanium Shape Memory Alloy and Carbon Fiber-Reinforced Polymer Matrix Composites

NASA Technical Reports Server (NTRS)

Quade, Derek J.; Jana, Sadhan; McCorkle, Linda S.

2018-01-01

Strips of nickel-titanium (NiTi) shape memory alloy (SMA) and carbon fiber-reinforced polymer matrix composite (PMC) were bonded together using multiple thin film adhesives and their mechanical strengths were evaluated under pullout test configuration. Tensile and lap shear tests were conducted to confirm the deformation of SMAs at room temperature and to evaluate the adhesive strength between the NiTi strips and the PMC. Optical and scanning electron microscopy techniques were used to examine the interfacial bonding after failure. Simple equations on composite tensile elongation were used to fit the experimental data on tensile properties. ABAQUS models were generated to show the effects of enhanced bond strength and the distribution of stress in SMA and PMC. The results revealed that the addition of thin film adhesives increased the average adhesive strength between SMA and PMC while halting the room temperature shape memory effect within the pullout specimen.

Advanced thermoplastic resins, phase 2

NASA Technical Reports Server (NTRS)

Brown, A. M.; Hill, S. G.; Falcone, A.

1991-01-01

High temperature structural resins are required for use on advanced aerospace vehicles as adhesives and composite matrices. NASA-Langley developed polyimide resins were evaluated as high temperature structural adhesives for metal to metal bonding and as composite matrices. Adhesive tapes were prepared on glass scrim fabric from solutions of polyamide acids of the semicrystalline polyimide LARC-CPI, developed at the NASA-Langley Research Center. Using 6Al-4V titanium adherends, high lap shear bond strengths were obtained at ambient temperature (45.2 MPa, 6550 psi) and acceptable strengths were obtained at elevated temperature (14.0 MPa, 2030 psi) using the Pasa-Jell 107 conversion coating on the titanium and a bonding pressure of 1.38 MPa (200 psi). Average zero degree composite tensile and compressive strengths of 1290 MPa (187 ksi) and 883 MPa (128 ksi) respectively were obtained at ambient temperature with unsized AS-4 carbon fiber reinforcement.

Temperature Effects on Adhesive Bond Strengths and Modulus for Commonly Used Spacecraft Structural Adhesives

NASA Technical Reports Server (NTRS)

Ojeda, Cassandra E.; Oakes, Eric J.; Hill, Jennifer R.; Aldi, Dominic; Forsberg, Gustaf A.

2011-01-01

A study was performed to observe how changes in temperature and substrate material affected the strength and modulus of an adhesive bondline. Seven different adhesives commonly used in aerospace bonded structures were tested. Aluminum, titanium and Invar adherends were cleaned and primed, then bonded using the manufacturer's recommendations. Following surface preparation, the coupons were bonded with the adhesives. The single lap shear coupons were then pull tested per ASTM D 1002 Standard Test Method for Apparent Shear Strength of Single- Lap-Joint over a temperature range from -150 deg C up to +150 deg C. The ultimate strength was calculated and the resulting data were converted into B-basis design allowables. Average and Bbasis results were compared. Results obtained using aluminum adherends are reported. The effects of using different adherend materials and temperature were also studied and will be reported in a subsequent paper. Dynamic Mechanical Analysis (DMA) was used to study variations in adhesive modulus with temperature. This work resulted in a highly useful database for comparing adhesive performance over a wide range of temperatures, and has facilitated selection of the appropriate adhesive for spacecraft structure applications.

Ceramic Inlays: Effect of Mechanical Cycling and Ceramic Type on Restoration-dentin Bond Strength.

PubMed

Trindade, F Z; Kleverlaan, C J; da Silva, L H; Feilzer, A J; Cesar, P F; Bottino, M A; Valandro, L F

2016-01-01

This study aimed to evaluate the bond strength between dentin and five different ceramic inlays in permanent maxillary premolars, with and without mechanical cycling. One hundred permanent maxillary premolars were prepared and divided into 10 groups (n=10) according to the ceramic system (IPS e.Max Press; IPS e.Max CAD; Vita PM9; Vita Mark II; and Vita VM7) and the mechanical cycling factor (with and without [100 N, 2 Hz, 1.2×10(6) cycles]). The inlays were adhesively cemented, and all of the specimens were cut into microbars (1×1 mm, nontrimming method), which were tested under microtensile loading. The failure mode was classified and contact angle, roughness, and microtopographic analyses were performed on each ceramic surface. The mechanical cycling had a significant effect (p=0.0087) on the bond strength between dentin and IPS e.max Press. The Vita Mark II group had the highest bond strength values under both conditions, with mechanical cycling (9.7±1.8 MPa) and without (8.2±1.9 MPa), while IPS e.Max CAD had the lowest values (2.6±1.6 and 2.2±1.4, respectively). The adhesive failure mode at the ceramic/cement interface was the most frequent. Vita Mark II showed the highest value of average roughness. IPS e.max Press and Vita Mark II ceramics presented the lowest contact angles. In conclusion, the composition and manufacturing process of ceramics seem to have an influence on the ceramic surface and resin cement bond strength. Mechanical cycling did not cause significant degradation on the dentin and ceramic bond strength under the configuration used.

Study of the physical properties of Ge-S-Ga glassy alloy

NASA Astrophysics Data System (ADS)

Rana, Anjli; Sharma, Raman

2018-05-01

In the present work, we have studied the effect of Ga doping on the physical properties of Ge20S80-xGax glassy alloy. The basic physical parameters which have important role in determining the structure and strength of the material viz. average coordination number, lone-pair electrons, mean bond energy, glass transition temperature, electro negativity, probabilities for bond distribution and cohesive energy have been computed theoretically for Ge-S-Ga glassy alloy. Here, the glass transition temperature and mean bond energy have been investigated using the Tichy-Ticha approach. The cohesive energy has been calculated by using chemical bond approach (CBA) method. It has been found that while average coordination number increases, all the other parameters decrease with the increase in Ga content in Ge-S-Ga system.

Effect of CO2, Nd:YAG and Er:YAG Lasers on Microtensile Bond Strength of Composite to Bleached-Enamel.

PubMed

Basir, Mahshid Mohammadi; Rezvani, Mohammad Bagher; Chiniforush, Nasim; Moradi, Zohreh

2016-01-01

Tooth restoration immediately after bleaching is challenging due to the potential problems in achieving adequate bond strength. The aim of this study was to evaluate the effect of surface treatment with ER:YAG, ND:YAG, CO2 lasers and 10% sodium ascorbate solution on immediate microtensile bond strength of composite resin to recently bleached enamel. Ninety sound molar teeth were randomly divided into three main groups (n:30) : NB (without bleaching), HB (bleached with 38% carbamide peroxide) and OB (bleached with Heydent bleaching gel assisted by diode laser). Each group was divided into five subgroups (n:6) : Si (without surface treatment), Er (Er:YAG laser), CO2 (CO2 laser), Nd (Nd:YAG laser) and As (Immersion in 10% sodium ascorbate solution). The bonding system was then applied and composite build-ups were constructed. The teeth were sectioned by low speed saw to obtain enamel- resin sticks and submitted to microtensile bond testing. Statistical analyses were done using two- way ANOVA, Tukey and Tamhane tests. µTBS of bleached teeth irradiated with ND:YAG laser was not significantly different from NB-Nd group. Microtensile bond strength of OB-Er group was higher than NB-Er and HB-Er groups. The mean µTBS of HB-CO2 group was higher than NB-CO2 group; the average µTBS of HB-As and OB-As groups was also higher than NB-As group. Use of Nd:YAG, CO2 lasers and 10% sodium ascorbate solution could improve the bond strength in home-bleached specimens. Application of ND:YAG laser on nonbleached specimens and Er:YAG laser on office-bleached specimens led to the highest µTBS in comparison to other surface treatments in each main group.

Numerical simulation of microstructural damage and tensile strength of snow

NASA Astrophysics Data System (ADS)

Hagenmuller, Pascal; Theile, Thiemo C.; Schneebeli, Martin

2014-01-01

This contribution uses finite-element analysis to simulate microstructural failure processes and the tensile strength of snow. The 3-D structure of snow was imaged by microtomography. Modeling procedures used the elastic properties of ice with bond fracture assumptions as inputs. The microstructure experiences combined tensile and compressive stresses in response to macroscopic tensile stress. The simulated nonlocalized failure of ice lattice bonds before or after reaching peak stress creates a pseudo-plastic yield curve. This explains the occurrence of acoustic events observed in advance of global failure. The measured and simulated average tensile strengths differed by 35%, a typical range for strength measurements in snow given its low Weibull modulus. The simulation successfully explains damage, fracture nucleation, and strength according to the geometry of the microstructure of snow and the mechanical properties of ice. This novel method can be applied to more complex snow structures including the weak layers that cause avalanches.

Photodiodes integration on a suspended ridge structure VOA using 2-step flip-chip bonding method

NASA Astrophysics Data System (ADS)

Kim, Seon Hoon; Kim, Tae Un; Ki, Hyun Chul; Kim, Doo Gun; Kim, Hwe Jong; Lim, Jung Woon; Lee, Dong Yeol; Park, Chul Hee

2015-01-01

In this works, we have demonstrated a VOA integrated with mPDs, based on silica-on-silicon PLC and flip-chip bonding technologies. The suspended ridge structure was applied to reduce the power consumption. It achieves the attenuation of 30dB in open loop operation with the power consumption of below 30W. We have applied two-step flipchip bonding method using passive alignment to perform high density multi-chip integration on a VOA with eutectic AuSn solder bumps. The average bonding strength of the two-step flip-chip bonding method was about 90gf.

Influence of electric field on the hydrogen bond network of methanol.

PubMed

Suresh, S J; Prabhu, Arun Laxman; Arora, Abhinav

2007-04-07

The understanding of the structure of hydrogen (H) bonding liquids in electric (E) fields is important in the context of several areas of research, such as electrochemistry, surface science, and thermodynamics of electrolyte solutions. We had earlier presented a general thermodynamic framework for this purpose, and had shown that the application of E field enhances H-bond interactions among water molecules. The present investigation with methanol suggests a different result-the H-bond structure, as indicated by the average number of H bonds per molecule, goes through a maxima with increasing field strength. This result is explained based on the symmetry in the location of the H-bonding sites in the two types of molecules.

The study of a light-activated albumin protein solder to bond layers of porcine small intestinal submucosa.

PubMed

Ware, Mark H; Buckley, Christine A

2003-01-01

This study investigated the feasibility of bonding layers of porcine small intestinal submucosa (SIS, Cook Biotech, Inc.) with a light-activated protein solder. SIS is an acellular, collagen-based extracellular matrix material that is approximately 100 microns thick. The solder consists of bovine serum albumin and indocyanine green dye (ICG) in deionized water. The solder is activated by an 808 nm diode laser, which denatures the albumin, causing the albumin to bond with the collagen of the tissue. The predictable absorption and thermal energy diffusion rates of ICG increase the chances of reproducible results. To determine the optimal condition for laser soldering SIS, the following parameters were varied: albumin concentration (from 30-45% (w/v) in increments of 5%), the concentration of ICG (from 0.5-2.0 mg/ml H2O) and the irradiance of the laser (10-64 W/cm2). While many of the solder compositions and laser irradiance combinations resulted in no bonding, a solder composition of 45% albumin, ICG concentration of 0.5 mg/ml H2O, and a laser irradiance of 21 W/cm2 did produce a bond between two pieces of SIS. The average shear strength of this bond was 29.5 +/- 17.1 kPa (n = 14). This compares favorably to our previous work using fibrin glue as an adhesive, in which the average shear strength was 27 +/- 15.8 kPa (n = 40).

Wafer-Level Hermetic Package by Low-Temperature Cu/Sn TLP Bonding with Optimized Sn Thickness

NASA Astrophysics Data System (ADS)

Wu, Zijian; Cai, Jian; Wang, Qian; Wang, Junqiang; Wang, Dejun

2017-10-01

In this paper, a wafer-level package with hermetic sealing by low-temperature Cu/Sn transient liquid phase (TLP) bonding for a micro-electromechanical system was introduced. A Cu bump with a Sn cap and sealing ring were fabricated simultaneously by electroplating. The model of Cu/Sn TLP bonding was established and the thicknesses of Cu and Sn were optimized after a series of bonding experiments. Cu/Sn wafer-level bonding was undertaken at 260°C for 30 min under a vacuum condition. An average shear strength of 50.36 MPa and a fine leak rate of 1.9 × 10-8 atm cc/s were achieved. Scanning electron microscope photos of the Cu/Sn/Cu interlayers were presented, and energy dispersive x-ray analysis was conducted simultaneously. The results showed that the Sn was completely consumed to form the stable intermetallic compound Cu3Sn. An aging test of 200 h at 200°C was conducted to test the performance of the hermetic sealing, while the results of shear strength, fine leak rate and bonding interface were also set out.

Dentine bond strength and antimicrobial activity evaluation of adhesive systems.

PubMed

André, Carolina Bosso; Gomes, Brenda Paula Figueiredo Almeida; Duque, Thais Mageste; Stipp, Rafael Nobrega; Chan, Daniel Chi Ngai; Ambrosano, Glaucia Maria Bovi; Giannini, Marcelo

2015-04-01

This study evaluated the dentine bond strength (BS) and the antibacterial activity (AA) of six adhesives against strict anaerobic and facultative bacteria. Three adhesives containing antibacterial components (Gluma 2Bond (glutaraldehyde)/G2B, Clearfil SE Protect (MDPB)/CSP and Peak Universal Bond (PUB)/chlorhexidine) and the same adhesive versions without antibacterial agents (Gluma Comfort Bond/GCB, Clearfil SE Bond/CSB and Peak LC Bond/PLB) were tested. The AA of adhesives and control groups was evaluated by direct contact method against four strict anaerobic and four facultative bacteria. After incubation, according to the appropriate periods of time for each microorganism, the time to kill microorganisms was measured. For BS, the adhesives were applied according to manufacturers' recommendations and teeth restored with composite. Teeth (n=10) were sectioned to obtain bonded beams specimens, which were tested after artificial saliva storage for one week and one year. BS data were analyzed using two-way ANOVA and Tukey test. Saliva storage for one year reduces the BS only for GCB. In general G2B and GCB required at least 24h for killing microorganisms. PUB and PLB killed only strict anaerobic microorganisms after 24h. For CSP the average time to eliminate the Streptococcus mutans and strict anaerobic oral pathogens was 30 min. CSB showed no AA against facultative bacteria, but had AA against some strict anaerobic microorganisms. Storage time had no effect on the BS for most of the adhesives. The time required to kill bacteria depended on the type of adhesive and never was less than 10 min. Most of the adhesives showed stable bond strength after one year and the Clearfil SE Protect may be a good alternative in restorative procedures performed on dentine, considering its adequate bond strength and better antibacterial activity. Copyright © 2015 Elsevier Ltd. All rights reserved.

Shear Bond Strength of Three Orthodontic Bonding Systems on Enamel and Restorative Materials.

PubMed

Hellak, Andreas; Ebeling, Jennifer; Schauseil, Michael; Stein, Steffen; Roggendorf, Matthias; Korbmacher-Steiner, Heike

2016-01-01

Objective. The aim of this in vitro study was to determine the shear bond strength (SBS) and adhesive remnant index (ARI) score of two self-etching no-mix adhesives (iBond ™ and Scotchbond ™ ) on different prosthetic surfaces and enamel, in comparison with the commonly used total etch system Transbond XT ™ . Materials and Methods . A total of 270 surfaces (1 enamel and 8 restorative surfaces, n = 30) were randomly divided into three adhesive groups. In group 1 (control) brackets were bonded with Transbond XT primer. In the experimental groups iBond adhesive (group 2) and Scotchbond Universal adhesive (group 3) were used. The SBS was measured using a Zwicki 1120 ™ testing machine. The ARI and SBS were compared statistically using the Kruskal-Wallis test ( P ≤ 0.05). Results . Significant differences in SBS and ARI were found between the control group and experimental groups. Conclusions . Transbond XT showed the highest SBS on human enamel. Scotchbond Universal on average provides the best bonding on all other types of surface (metal, composite, and porcelain), with no need for additional primers. It might therefore be helpful for simplifying bonding in orthodontic procedures on restorative materials in patients. If metal brackets have to be bonded to a metal surface, the use of a dual-curing resin is recommended.

Hydrogen bonds, interfacial stiffness moduli, and the interlaminar shear strength of carbon fiber-epoxy matrix composites

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cantrell, John H., E-mail: john.h.cantrell@nasa.gov

2015-03-15

The chemical treatment of carbon fibers used in carbon fiber-epoxy matrix composites greatly affects the fraction of hydrogen bonds (H-bonds) formed at the fiber-matrix interface. The H-bonds are major contributors to the fiber-matrix interfacial shear strength and play a direct role in the interlaminar shear strength (ILSS) of the composite. The H-bond contributions τ to the ILSS and magnitudes K{sub N} of the fiber-matrix interfacial stiffness moduli of seven carbon fiber-epoxy matrix composites, subjected to different fiber surface treatments, are calculated from the Morse potential for the interactions of hydroxyl and carboxyl acid groups formed on the carbon fiber surfacesmore » with epoxy receptors. The τ calculations range from 7.7 MPa to 18.4 MPa in magnitude, depending on fiber treatment. The K{sub N} calculations fall in the range (2.01 – 4.67) ×10{sup 17} N m{sup −3}. The average ratio K{sub N}/|τ| is calculated to be (2.59 ± 0.043) × 10{sup 10} m{sup −1} for the seven composites, suggesting a nearly linear connection between ILSS and H-bonding at the fiber-matrix interfaces. The linear connection indicates that τ may be assessable nondestructively from measurements of K{sub N} via a technique such as angle beam ultrasonic spectroscopy.« less

Photochemical tissue bonding with chitosan adhesive films

PubMed Central

2010-01-01

Background Photochemical tissue bonding (PTB) is a promising sutureless technique for tissue repair. PTB is often achieved by applying a solution of rose bengal (RB) between two tissue edges, which are irradiated by a green laser to crosslink collagen fibers with minimal heat production. In this study, RB has been incorporated in chitosan films to create a novel tissue adhesive that is laser-activated. Methods Adhesive films, based on chitosan and containing ~0.1 wt% RB were manufactured and bonded to calf intestine by a solid state laser (λ = 532 nm, Fluence~110 J/cm2, spot size~0.5 cm). A single-column tensiometer, interfaced with a personal computer, tested the bonding strength. K-type thermocouples recorded the temperature (T) at the adhesive-tissue interface during laser irradiation. Human fibroblasts were also seeded on the adhesive and cultured for 48 hours to assess cell growth. Results The RB-chitosan adhesive bonded firmly to the intestine with adhesion strength of 15 ± 2 kPa, (n = 31). The adhesion strength dropped to 0.5 ± 0.1 (n = 8) kPa when the laser was not applied to the adhesive. The average temperature of the adhesive increased from 26°C to 32°C during laser exposure. Fibroblasts grew confluent on the adhesive without morphological changes. Conclusion A new biocompatible chitosan adhesive has been developed that bonds photochemically to tissue with minimal temperature increase. PMID:20825632

Resin-dentin bond stability and physical characterization of a two-step self-etching adhesive system associated with TiF4.

PubMed

Torres, Gabriele Barbosa; da Silva, Tânia Mara; Basting, Rosanna Tarkany; Bridi, Enrico Coser; França, Fabiana Mantovani Gomes; Turssi, Cecilia Pedroso; do Amaral, Flávia Lucisano Botelho; de Paiva Gonçalves, Sérgio Eduardo; Basting, Roberta Tarkany

2017-10-01

To evaluate the bond strength to superficial (SD) and deep (DD) dentin after the use of 2.5% (T2.5%) or 4% (T4%) titanium tetrafluoride (TiF 4 ) in aqueous solution as a dentin pretreatment, or when incorporated into the primer (T2.5%P and T4%P) of an adhesive system (Clearfil SE Bond/CL). Degree of conversion (DC), particle size (PS), polydispersity index (PI) and zeta potential (ZP) of the solutions were evaluated. Fifty molars were sectioned longitudinally to obtain two slices of each tooth, which were demarcated into SD and DD. Treatments were applied (n=10): CL; T2.5%; T4%; T2.5%P; T4%P. After 24h or 180days storage, microshear bond strength tests were performed. The DC values of T2.5%P and T4%P were evaluated by FTIR. PS, PI and ZP were measured using dynamic light scattering. Analysis of mixed models showed significant effect of concentration of TiF 4 * solution * storage time (p=0.0075). There were higher bond strength values in SD than in DD (p=0.0105) for all treatments in both times. The failure mode showed adhesive failures in the majority of groups, irrespective of depth and time (p=0.3746). The bond strength values were not affected by treatments. Lower average particle size was observed for T2.5%P and T4%P at baseline. T2.5% and T4% showed a trend towards agglomeration. Higher bond strength values were achieved at SD for all treatments and times. The failure modes observed were adhesive. TiF 4 incorporation did not affect DC. T2.5%P and T4%P presented excellent stability over time. Copyright © 2017 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Bond strength evaluation in adhesive joints using NDE and DIC methods

NASA Astrophysics Data System (ADS)

Poudel, Anish

Adhesive bonding of graphite epoxy composite laminates to itself or traditional metal alloys in modern aerospace and aircraft structural applications offers an excellent opportunity to use the most efficient and intelligent combination of materials available thus providing an attractive package for efficient structural designs. However, one of the major issues of adhesive bonding is the occasional formation of interfacial defects such as kissing or weak bonds in the bondline interface. Also, there are shortcomings of existing non-destructive evaluation (NDE) methods to non-destructively detect/characterize these interfacial defects and reliably predicting the bond shear strength. As a result, adhesive bonding technology is still not solely implemented in primary structures of an aircraft. Therefore, there is a greater demand for a novel NDE tool that can meet the existing aerospace requirement for adhesive bondline characterization. This research implemented a novel Acoustography ultrasonic imaging and digital image correlation (DIC) technique to detect and characterize interfacial defects in the bondline and determine bond shear strength in adhesively bonded composite-metal joints. Adhesively bonded Carbon Fiber Reinforced Plastic (CFRP) laminate and 2024-T3 Aluminum single lap shear panels subjected to various implanted kissing/weak bond defects were the primary focus of this study. Kissing/weak bonds were prepared by controlled surface contamination in the composite bonding surface and also by improperly mixing the adhesive constituent. SEM analyses were also conducted to understand the surface morphology of substrates and their interaction with the contaminants. Morphological changes were observed in the microscopic scale and the chemical analysis confirmed the stability of the contaminant at or very close to the interface. In addition, it was also demonstrated that contaminants migrated during the curing of the adhesive from CFRP substrate which caused a decrease of bond shear strength in single lap shear test samples. Through-transmission ultrasonics (TTU) Acoustography at 3.8 MHz showed promising results on the detectability of bondline defects in adhesively bonded CFRP-Al lap shear test samples. A correlation between Acoustography ultrasonic attenuation and average bond shear strength in CFRP-Al lap shear panels demonstrated that differential attenuation increased with the reduction of the bond shear strength. Similarly, optical DIC tests were conducted to identify and quantify kissing bond defects in CFRP-Al single lap shear joints. DIC results demonstrated changes in the normal strain (epsilonyy) contour map of the contaminated specimens at relatively lower load levels (15% ~ 30% of failure loads). Kissing bond regions were characterized by negative strains, and these were attributed to high compressive bending strains and the localized disbonding taking placed at the bondline interface as a result of the load application. It was also observed that contaminated samples suffered from more compressive strains (epsilonyy) compared to the baseline sample along the loading direction and they suffered from less compressive strains (epsilonxx) compared to the baseline sample perpendicular to the loading direction. This demonstrated the adverse effect of the kissing bond on the adhesive joint integrity. This was a very significant finding for the reason that hybrid ultrasonic DIC is being developed as a faster, more efficient, and more reliable NDE technique for determining bond quality and predicting bond shear strength in adhesively bonded structures.

Adhesive bonding of super-elastic titanium-nickel alloy castings with a phosphate metal conditioner and an acrylic adhesive.

PubMed

Matsumura, H; Tanoue, N; Yanagida, H; Atsuta, M; Koike, M; Yoneyama, T

2003-06-01

The purpose of the current study was to evaluate the bonding characteristics of super-elastic titanium-nickel (Ti-Ni) alloy castings. Disk specimens were cast from a Ti-Ni alloy (Ti-50.85Ni mol%) using an arc centrifugal casting machine. High-purity titanium and nickel specimens were also prepared as experimental references. The specimens were air-abraded with alumina, and bonded with an adhesive resin (Super-Bond C & B). A metal conditioner containing a phosphate monomer (Cesead II Opaque Primer) was also used for priming the specimens. Post-thermocycling average bond strengths (MPa) of the primed groups were 41.5 for Ti-Ni, 30.4 for Ti and 19.5 for Ni, whereas those of the unprimed groups were 21.6 for Ti, 19.3 for Ti-Ni and 9.3 for Ni. Application of the phosphate conditioner elevated the bond strengths of all alloy/metals (P < 0.05). X-ray fluorescence analysis revealed that nickel was attached to the debonded resin surface of the resin-to-nickel bonded specimen, indicating that corrosion of high-purity nickel occurred at the resin-nickel interface. Durable bonding to super-elastic Ti-Ni alloy castings can be achieved with a combination of a phosphate metal conditioner and a tri-n-butylborane-initiated adhesive resin.

Shear Bond Strength of Three Orthodontic Bonding Systems on Enamel and Restorative Materials

PubMed Central

Ebeling, Jennifer; Schauseil, Michael; Stein, Steffen; Roggendorf, Matthias; Korbmacher-Steiner, Heike

2016-01-01

Objective. The aim of this in vitro study was to determine the shear bond strength (SBS) and adhesive remnant index (ARI) score of two self-etching no-mix adhesives (iBond™ and Scotchbond™) on different prosthetic surfaces and enamel, in comparison with the commonly used total etch system Transbond XT™. Materials and Methods. A total of 270 surfaces (1 enamel and 8 restorative surfaces, n = 30) were randomly divided into three adhesive groups. In group 1 (control) brackets were bonded with Transbond XT primer. In the experimental groups iBond adhesive (group 2) and Scotchbond Universal adhesive (group 3) were used. The SBS was measured using a Zwicki 1120™ testing machine. The ARI and SBS were compared statistically using the Kruskal–Wallis test (P ≤ 0.05). Results. Significant differences in SBS and ARI were found between the control group and experimental groups. Conclusions. Transbond XT showed the highest SBS on human enamel. Scotchbond Universal on average provides the best bonding on all other types of surface (metal, composite, and porcelain), with no need for additional primers. It might therefore be helpful for simplifying bonding in orthodontic procedures on restorative materials in patients. If metal brackets have to be bonded to a metal surface, the use of a dual-curing resin is recommended. PMID:27738633

Shear Bond Strength of Superficial, Intermediate and Deep Dentin In Vitro with Recent Generation Self-etching Primers and Single Nano Composite Resin.

PubMed

Singh, Kulshrest; Naik, Rajaram; Hegde, Srinidhi; Damda, Aftab

2015-01-01

This in vitro study is intended to compare the shear bond strength of recent self-etching primers to superficial, intermediate, and deep dentin levels. All teeth were sectioned at various levels and grouped randomly into two experimental groups and two control groups having three subgroups. The experimental groups consisted of two different dentin bonding system. The positive control group consisted of All Bond 2 and the negative control group was without the bonding agent. Finally, the specimens were subjected to shear bond strength study under Instron machine. The maximum shear bond strengths were noted at the time of fracture. The results were statistically analyzed. Comparing the shear bond strength values, All Bond 2 (Group III) demonstrated fairly higher bond strength values at different levels of dentin. Generally comparing All Bond 2 with the other two experimental groups revealed highly significant statistical results. In the present investigation with the fourth generation, higher mean shear bond strength values were recorded compared with the self-etching primers. When intermediate dentin shear bond strength was compared with deep dentin shear bond strength statistically significant results were found with Clearfil Liner Bond 2V, All Bond 2 and the negative control. There was a statistically significant difference in shear bond strength values both with self-etching primers and control groups (fourth generation bonding system and without bonding system) at superficial, intermediate, and deep dentin. There was a significant fall in bond strength values as one reaches deeper levels of dentin from superficial to intermediate to deep.

Preliminary assessment of metal-porcelain bonding strength of CoCrW alloy after 3wt.% Cu addition.

PubMed

Lu, Yanjin; Zhao, Chaoqian; Ren, Ling; Guo, Sai; Gan, Yiliang; Yang, Chunguang; Wu, Songquan; Lin, Junjie; Huang, Tingting; Yang, Ke; Lin, Jinxin

2016-06-01

In this work, a novel Cu-bearing CoCrW alloy fabricated by selective laser melting for dental application has been studied. For its successful application, the bonding strength of metal-porcelain is essential to be systematically investigated. Therefore, the aim of this study was to evaluate the metal-porcelain bonding strength of CoCrWCu alloy by three-point bending test, meanwhile the Ni-free CoCrW alloy was used as control. The oxygen content was investigated by an elemental analyzer; X-ray photoelectron spectroscopy (XPS) was used to analyze the surface chemical composition of CoCrW based alloy after preoxidation treatment; the fracture mode was investigated by X-ray energy spectrum analysis (EDS) and scanning electron microscope (SEM). Result from the oxygen content analysis showed that the content of oxygen dramatically increased after the Cu addition. And the XPS suggested that Co-oxidation, Cr2O3, CrO2, WO3, Cu2O and CuO existed on the preoxidated surface of the CoCrWCu alloy; the three-point bending test showed that the bonding strength of the CoCrWCu alloy was 43.32 MPa, which was lower than that of the CoCrW group of 47.65 MPa. However, the average metal-porcelain bonding strength is significantly higher than the minimum value in the ISO 9693 standard. Results from the SEM images and EDS indicated that the fracture mode of CoCrWCu-porcelain was mixed between cohesive and adhesive. Based on the results obtained in this study, it can be indicated that the Cu-bearing CoCrW alloy fabricated by the selective laser melting is a promising candidate for use in dental application. Copyright © 2016 Elsevier B.V. All rights reserved.

Liquefaction of kenaf (Hibiscus cannabinus L.) core for wood laminating adhesive.

PubMed

Juhaida, M F; Paridah, M T; Mohd Hilmi, M; Sarani, Z; Jalaluddin, H; Mohamad Zaki, A R

2010-02-01

A study was carried out to produce polyurethane (PU) as a wood laminating adhesive from liquefied kenaf core (LKC) polyols by reacting it with toluene-2,4-diisocyanate (TDI) and 1,4-butanediol (BDO). The LKC polyurethane (LKCPU) adhesive has a molecular weight (MW) of 2666, viscosity of 5370 mPa s, and solids content of 86.9%. The average shear strength of the rubberwood (RW) bonded with LKCPU adhesive was 2.9 MPa. Most of the sheared specimens experienced a total adhesive failure. The formation of air bubbles through the liberation of carbon dioxide was observed to reduce the adhesive penetration and bonding strength which was obviously seen on the sheared specimens. The percentage of catalyst used can be varied based on the usage and working time needed. Nonetheless, the physical properties of LKCPU produced in this work had shown good potential as edge-bonding adhesive.

An energetic scale for equilibrium H/D fractionation factors illuminates hydrogen bond free energies in proteins

PubMed Central

Cao, Zheng; Bowie, James U

2014-01-01

Equilibrium H/D fractionation factors have been extensively employed to qualitatively assess hydrogen bond strengths in protein structure, enzyme active sites, and DNA. It remains unclear how fractionation factors correlate with hydrogen bond free energies, however. Here we develop an empirical relationship between fractionation factors and free energy, allowing for the simple and quantitative measurement of hydrogen bond free energies. Applying our empirical relationship to prior fractionation factor studies in proteins, we find: [1] Within the folded state, backbone hydrogen bonds are only marginally stronger on average in α-helices compared to β-sheets by ∼0.2 kcal/mol. [2] Charge-stabilized hydrogen bonds are stronger than neutral hydrogen bonds by ∼2 kcal/mol on average, and can be as strong as –7 kcal/mol. [3] Changes in a few hydrogen bonds during an enzyme catalytic cycle can stabilize an intermediate state by –4.2 kcal/mol. [4] Backbone hydrogen bonds can make a large overall contribution to the energetics of conformational changes, possibly playing an important role in directing conformational changes. [5] Backbone hydrogen bonding becomes more uniform overall upon ligand binding, which may facilitate participation of the entire protein structure in events at the active site. Our energetic scale provides a simple method for further exploration of hydrogen bond free energies. PMID:24501090

In vitro evaluation of an adhesive monomer as a bonding agent for orthodontic brackets to primary teeth and nickel-chromium ion crowns.

PubMed

Ergas, R P; Hondrum, S O; Mathieu, G P; Koonce, J D

1995-01-01

The adhesive monomer, Clearfil New Bond, was used to enhance the bond strength between orthodontic brackets and primary molars, premolars, and NiCr crowns. Twenty specimens of each had this dental adhesive applied according to the manufacturer's instructions in addition to a chemically cured composite material. The remaining specimens (20 each) were bonded without the adhesive monomer. Shear bond strengths were determined using a universal testing machine. Fracture sites were examined to determine the type of bond failure. All bond strengths were significantly increased with the addition of Clearfil New Bond (P < or = 0.0001). The shear bond strength to NiCr crowns with the addition of the adhesive monomer was 7.76 kg. This is comparable to the shear bond strength observed for primary molars (8.66 kg) and premolars (8.65 kg) without adhesive monomer. The observed decrease in adhesive bond failures with the addition of Clearfil New Bond indicated a stronger shear bond strength between the tooth surface and the bracket base. Clearfil New Bond can significantly increase the shear bond strength of orthodontic brackets to both primary molars and premolars. Additionally, it was shown that orthodontic brackets can be successfully bonded to Ni-Cr crowns at strengths comparable to primary or permanent enamel.

Influence of Abutment Design on Stiffness, Strength, and Failure of Implant-Supported Monolithic Resin Nano Ceramic (RNC) Crowns.

PubMed

Joda, Tim; Huber, Samuel; Bürki, Alexander; Zysset, Philippe; Brägger, Urs

2015-12-01

Recent technical development allows the digital manufacturing of monolithic reconstructions with high-performance materials. For implant-supported crowns, the fixation requires an abutment design onto which the reconstruction can be bonded. The aim of this laboratory investigation was to analyze stiffness, strength, and failure modes of implant-supported, computer-assisted design and computer-aided manufacturing (CAD/CAM)-generated resin nano ceramic (RNC) crowns bonded to three different titanium abutments. Eighteen monolithic RNC crowns were produced and loaded in a universal testing machine under quasi-static condition according to DIN ISO 14801. With regard to the type of titanium abutment, three groups were defined: (1) prefabricated cementable standard; (2) CAD/CAM-constructed individualized; and (3) novel prefabricated bonding base. Stiffness and strength were measured and analyzed statistically with Wilcoxon rank sum test. Sections of the specimens were examined microscopically. Stiffness demonstrated high stability for all specimens loaded in the physiological loading range with means and standard deviations of 1,579 ± 120 N/mm (group A), 1,733 ± 89 N/mm (group B), and 1,704 ± 162 N/mm (group C). Mean strength of the novel prefabricated bonding base (group C) was 17% lower than of the two other groups. Plastic deformations were detectable for all implant-abutment crown connections. Monolithic implant crowns made of RNC seem to represent a feasible and stable prosthetic construction under laboratory testing conditions with strength higher than the average occlusal force, independent of the different abutment designs used in this investigation. © 2014 Wiley Periodicals, Inc.

Effect of ultraviolet light irradiation and sandblasting treatment on bond strengths between polyamide and chemical-cured resin.

PubMed

Asakawa, Yuya; Takahashi, Hidekazu; Iwasaki, Naohiko; Kobayashi, Masahiro

2014-01-01

The aim of this study was to evaluate the effects of ultraviolet light (UV) irradiation and sandblasting treatment on the shear bond strength between polyamide and chemical-cured resin. Three types of commercial polyamides were treated using UV irradiation, sandblasting treatment, and a combining sandblasting and UV irradiation. The shear bond strength was measured and analyzed using the Kruskal-Wallis test (α=0.05). Comparing shear bond strengths without surface treatment, from 4.1 to 5.7 MPa, the UV irradiation significantly increased the shear bond strengths except for Valplast, whose shear bond strengths ranged from 5.2 to 9.3 MPa. The sandblasting treatment also significantly increased the shear bond strengths (8.0 to 11.4 MPa). The combining sandblasting and UV irradiation significantly increased the shear bond strengths (15.2 to 18.3 MPa) comparing without surface treatment. This combined treatment was considered the most effective at improving the shear bond strength between polyamide and chemical-cured resin.

Relationship between thin-film bond strength as measured by a scratch test, and indentation hardness for bonding agents.

PubMed

Kusakabe, Shusuke; Rawls, H Ralph; Hotta, Masato

2016-03-01

To evaluate thin-film bond strength between a bonding agent and human dentin, using a scratch test, and the characteristics and accuracy of measurement. One-step bonding agents (BeautiBond; Bond Force; Adper Easy Bond; Clearfil tri-S Bond) and two-step bonding agents (Cleafil SE Bond; FL-Bond II) were investigated in this study. Flat dentin surfaces were prepared for extracted human molars. The dentin surfaces were ground and bonding agents were applied and light cured. The thin-film bond strength test of the specimens was evaluated by the critical load at which the coated bonding agent failed and dentin appeared. The scratch mark sections were then observed under a scanning electron microscope. Indentation hardness was evaluated by the variation in depth under an applied load of 10gf. Data were compared by one-way ANOVA with the Scheffé's post hoc multiple comparison test (p<0.05). In addition, thin-film bond strength and indentation hardness were analyzed using analysis of correlation and covariance. The thin-film bond strength of two-step bonding agents were found to be significantly higher than that of one-step bonding agents with small standard deviations. Scratch marks consistently showed adhesive failure in the vicinity of the bonding agent/dentin interface. The indentation hardness showed a trend that two-step bonding agents have greater hardness than one-step bonding agents. A moderately significant correlation (r(2)=0.31) was found between thin-film bond strength and indentation hardness. Thin-film bond strength test is a valid and reliable means of evaluating bond strength in the vicinity of the adhesive interface and is more accurate than other methods currently in use. Further, the thin-film bond strength is influenced by the hardness of the cued bonding agent. Copyright © 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Strength of bond with Comspan Opaque to three silicoated alloys and titanium.

PubMed

Hansson, O

1990-06-01

In Sweden high-gold alloys or cobalt-chromium alloys are used for resin-bonded prostheses. The bond strength between a resin cement and different sandblasted or silicoated metals were measured before and after thermocycling; in connection with this some rapid thermocycling methods were studied. The effect of different storage times and different protection coatings on bond strength were tested. Finally, the influence of rubbing and contamination with saliva on bond strength were investigated. Silicoating increased the bond strength significantly. The highest bond strengths were these of silicoated Wirobond and titanium, unsusceptible to thermal stress; the bond strengths of the sandblasted metals were the weakest, and sensitive to thermocycling as well. The influence on bond strength for silicoated gold alloys, protected with an unpolymerized composite resin coating, stored in sealed plastic bags up to 7 days, was negligible. Rubbing and contamination with saliva did not influence bond strength. Preferably, silicoated Wirobond and titanium should be used for resin-bonded prostheses, but gold alloys may still be adequate for clinical use. The experimental method described for storing, sealing, and cleaning the silicoated metal surfaces in this article can be recommended for laboratory and clinical use.

Experimental study of self-compacted concrete in hardened state

NASA Astrophysics Data System (ADS)

Parra Costa, Carlos Jose

The main aim of this work is to investigate the hardened behaviour of Self-Compacting Concrete (SCC). Self compacting Concrete is a special concrete that can flow in its gravity and fill in the formwork alone to its self-weight, passing through the bars and congested sections without the need of any internal or external vibration, while maintaining adequate homogeneity. SCC avoids most of the materials defects due to bleeding or segregation. With regard to its composition, SCC consists of the same components as traditional vibrated concrete (TC), but in different proportions. Thus, the high amount of superplasticizer and high powder content have to taken into account. The high workability of SCC does not allow to use traditional methods for measuring the fresh state properties, so new tests has developed (slump-flow, V-funnel, L-box, and others). The properties of the hardened SCC, which depend on the mix design, should be different from traditional concrete. In order to study the possible modifications of SCC hardened state properties, a review of the bibliography was done. The state of art was focused on the mechanical behaviour (compressive strength, tension strength and elastic modulus), on bond strength of reinforcement steel, and on material durability. The experimental program consisted in the production of two types of concretes: Self-Compacting Concrete and Traditional Concrete. Four different dosages was made with three different water/cement ratio and two strength types of Portland cement, in order to cover the ordinary strength used in construction. Based on this study it can be concluded that compressive strength of SCC and TC are similar (the differences are lesser than 10%), whereas the tensile strength of TC are up to 18% higher. The values of elastic modulus of both concrete are similar. On the other hand, in the ultimate state the bond strength of SCC and TC is similar, although SCC shows higher bond stiffness in the serviceability state (initial displacement). Thus SCC reaches higher average bond strength. Although the variation in bond strength at different elevations, due to top-bar effect, is also observed in SCC the extent is less significant than that of TC. Finally, tests show that water depth penetration under pressure is much lower for SCC than for TC.

Influence of technique and manipulation on self-adhesive resin cements used to cement intraradicular posts.

PubMed

Shiratori, Fábio Kenji; Valle, Accácio Lins do; Pegoraro, Thiago Amadei; Carvalho, Ricardo Marins; Pereira, Jefferson Ricardo

2013-07-01

Resin cements are widely used to cement intraradicular posts, but bond strength is significantly influenced by the technique and material used for cementation. The purpose of this study was to evaluate the bond strength of 3 self-adhesive cements used to cement intraradicular glass fiber posts. The cements all required different application and handling techniques. Forty-five human maxillary canines were selected and randomly divided into 3 groups n= 15 by drawing lots: Group BIS - Biscem, Group BRE - Breeze, and Group MAX - Maxcem. Each group was divided into 3 subgroups according to application and handling techniques: Sub-group A - Automix/Point tip applicator, Sub-group L - Handmix/Lentulo, and Sub-group C - Handmix/Centrix. Cementation of the posts was performed according to the manufacturers' instructions. The push-out test was performed with a crosshead speed of 0.5 mm/min, and bond strength was expressed in megapascals. The results were evaluated by 2-way ANOVA and the all pairwise multiple comparison procedures (Tukey test) (α=.05). Breeze cement showed the highest average for the subgroups A, L, and C when compared to the Biscem cement and Maxcem Elite (P<.05). Statistically significant differences among the subgroups were only observed for Biscem. This study shows that application and handling techniques may influence the bond strength of different self-adhesive cements when used for intraradicular post cementation. Copyright © 2013 The Editorial Council of the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.

Effect of additional etching and ethanol-wet bonding on the dentin bond strength of one-step self-etch adhesives

PubMed Central

Ahn, Joonghee; Jung, Kyoung-Hwa; Son, Sung-Ae; Hur, Bock; Kwon, Yong-Hoon

2015-01-01

Objectives This study examined the effects of additional acid etching on the dentin bond strength of one-step self-etch adhesives with different compositions and pH. The effect of ethanol wetting on etched dentin bond strength of self-etch adhesives was also evaluated. Materials and Methods Forty-two human permanent molars were classified into 21 groups according to the adhesive types (Clearfil SE Bond [SE, control]; G-aenial Bond [GB]; Xeno V [XV]; Beauti Bond [BB]; Adper Easy Bond [AE]; Single Bond Universal [SU]; All Bond Universal [AU]), and the dentin conditioning methods. Composite resins were placed on the dentin surfaces, and the teeth were sectioned. The microtensile bond strength was measured, and the failure mode of the fractured specimens was examined. The data were analyzed statistically using two-way ANOVA and Duncan's post hoc test. Results In GB, XV and SE (pH ≤ 2), the bond strength was decreased significantly when the dentin was etched (p < 0.05). In BB, AE and SU (pH 2.4 - 2.7), additional etching did not affect the bond strength (p > 0.05). In AU (pH = 3.2), additional etching increased the bond strength significantly (p < 0.05). When adhesives were applied to the acid etched dentin with ethanol-wet bonding, the bond strength was significantly higher than that of the no ethanol-wet bonding groups, and the incidence of cohesive failure was increased. Conclusions The effect of additional acid etching on the dentin bond strength was influenced by the pH of one-step self-etch adhesives. Ethanol wetting on etched dentin could create a stronger bonding performance of one-step self-etch adhesives for acid etched dentin. PMID:25671215

Shear bond strength of a new one-bottle dentin adhesive.

PubMed

Swift, E J; Bayne, S C

1997-08-01

To test the shear bond strength of a new adhesive, 3M Single Bond, to dentin surfaces containing different degrees of moisture. Two commercially available one-bottle adhesives (Prime & Bond, One-Step) and a conventional three-step system (Scotchbond Multi-Purpose Plus) were included for comparison. 120 bovine teeth were embedded in acrylic and the labial surfaces were polished to 600 grit to create standardized dentin surfaces for testing. Resin composite was bonded to dentin using a gelatin capsule technique. Four adhesive systems were evaluated with three different degrees of surface moisture (moist, wet, and overwet). Shear bond strengths of adhesives to dentin were determined using a universal testing machine and analyzed by ANOVA and Tukey's post hoc tests. Single Bond had mean shear bond strengths of 19.2, 23.2 and 20.3 MPa to moist, wet, and overwet dentin, respectively. Bond strengths of the three-component system Scotchbond Multi-Purpose Plus ranged from 23.1 to 25.3 MPa, but were not significantly higher than the values for Single Bond. Prime & Bond had bond strengths similar to those of Single Bond, but One-Step had significantly lower bond strengths (P < 0.05) in the wet and overwet conditions.

Shear bond strength of one-step self-etch adhesives: pH influence

PubMed Central

Poggio, Claudio; Beltrami, Riccardo; Scribante, Andrea; Colombo, Marco; Chiesa, Marco

2015-01-01

Background: The aim of this study was to compare the shear bond strength of four one-step self-etch adhesives with different pH values to enamel and dentin. Materials and Methods: In this in vitro study, 200 bovine permanent mandibular incisors were used. Four one-step self-etch adhesives with different pH values were tested both on enamel and on dentin: Adper™ Easy Bond Self-Etch Adhesive (pH = 0.8-1), Futurabond NR (pH=2), G-aenial Bond (pH = 1.5), Clearfil S3 Bond (pH = 2.7). After adhesive systems application, a nanohybrid composite resin was inserted into the bonded surface. The specimens were placed in a universal testing machine. The shear bond strength was performed at a cross-head speed of 1 mm/min until the sample rupture. The shear bond strength values (MPa) of the different groups were compared with analysis of variance after that Kolmogorov and Smirnov tests were applied to assess normality of distributions. P < 0.05 was considered as significant. Results: In enamel shear bond strength, the highest shear bond strength values were reported with Futurabond NR (P < 0.01); however, no significant differences were found with Clearfil S3 Bond. The others adhesive systems showed lower shear bond strength values with significant differences between them (P < 0.05). When comparing the dentin shear bond strength, the lowest shear bond strength values were reported with Clearfil S3 Bond (P < 0.05), while there were no significant differences among the other three products (P > 0.05). Conclusion: The pH values of adhesive systems did not influence significantly their shear bond strength to enamel or dentin. PMID:26005459

Analysis of Adhesively Bonded Ceramics Using an Asymmetric Wedge Test

DTIC Science & Technology

2008-12-01

4 Figure 2. Average crack ...flexure specimen. The flaw, indicated by the white arrow, is a subsurface semi-elliptical crack induced by surface machining damage...strength-limiting orthogonal surface machining crack in an alumina flexure specimen coated with a single layer of film adhesive. The white arrow

SEMICONDUCTOR TECHNOLOGY: Wafer level hermetic packaging based on Cu-Sn isothermal solidification technology

NASA Astrophysics Data System (ADS)

Yuhan, Cao; Le, Luo

2009-08-01

A novel wafer level bonding method based on Cu-Sn isothermal solidification technology is established. A multi-layer sealing ring and the bonding processing are designed, and the amount of solder and the bonding parameters are optimized based on both theoretical and experimental results. Verification shows that oxidation of the solder layer, voids and the scalloped-edge appearance of the Cu6Sn5 phase are successfully avoided. An average shear strength of 19.5 MPa and an excellent leak rate of around 1.9 × 10-9 atm cc/s are possible, meeting the demands of MIL-STD-883E.

Comparative evaluation of shear bond strength of metallic brackets bonded with two different bonding agents under dry conditions and with saliva contamination.

PubMed

Khanehmasjedi, Mashallah; Naseri, Mohammad Ali; Khanehmasjedi, Samaneh; Basir, Leila

2017-02-01

This study compared the shear bond strength of metallic brackets bonded with Single Bond and Assure bonding agents under dry and saliva-contamination conditions. Sixty sound premolar teeth were selected, and stainless-steel brackets were bonded on enamel surfaces with Single Bond and Assure bonding agents under dry condition or with saliva contamination. Shear bond strength values of brackets were measured in a universal testing machine. The adhesive remnant index scores were determined after debonding of the brackets under a stereomicroscope. One-way analysis of variance (ANOVA) was used to analyze bond strength. Two-by-two comparisons were made with post hoc Tukey tests (p<0.001). Frequencies of adhesive remnant index scores were analyzed by Kruskal-Wallis test. Bond strength values of brackets to tooth structure were 9.29±8.56 MPa and 21.25±8.93 MPa with the use of Assure resin bonding agent under saliva-contamination and dry conditions, respectively. These values were 10.13±6.69 MPa and 14.09±6.6 MPa, respectively, under the same conditions with the use of Single Bond adhesive. Contamination with saliva resulted in a significant decrease in the bond strength of brackets to tooth structure with the application of Assure adhesive resin (p<0.001). There were no significant differences in the adhesive remnant index scores between the study groups. Application of Single Bond and Assure bonding agents resulted in adequate bond strength of brackets to tooth structures. Contamination with saliva significantly decreased the bond strength of Assure bonding agent compared with dry conditions. Copyright © 2016. Published by Elsevier Taiwan LLC.

Comparison of enamel bond fatigue durability of universal adhesives and two-step self-etch adhesives in self-etch mode.

PubMed

Tsujimoto, Akimasa; Barkmeier, Wayne W; Hosoya, Yumiko; Nojiri, Kie; Nagura, Yuko; Takamizawa, Toshiki; Latta, Mark A; Miyazaki, Masashi

2017-10-01

To comparatively evaluate universal adhesives and two-step self-etch adhesives for enamel bond fatigue durability in self-etch mode. Three universal adhesives (Clearfil Universal Bond; G-Premio Bond; Scotchbond Universal Adhesive) and three two-step self-etch adhesives (Clearfil SE Bond; Clearfil SE Bond 2; OptiBond XTR) were used. The initial shear bond strength and shear fatigue strength of the adhesive to enamel in self-etch mode were determined. The initial shear bond strengths of the universal adhesives to enamel in self-etch mode was significantly lower than those of two-step self-etch adhesives and initial shear bond strengths were not influenced by type of adhesive in each adhesive category. The shear fatigue strengths of universal adhesives to enamel in self-etch mode were significantly lower than that of Clearfil SE Bond and Clearfil SE Bond 2, but similar to that OptiBond XTR. Unlike two-step self-etch adhesives, the initial shear bond strength and shear fatigue strength of universal adhesives to enamel in self-etch mode was not influenced by the type of adhesive. This laboratory study showed that the enamel bond fatigue durability of universal adhesives was lower than Clearfil SE Bond and Clearfil SE Bond 2, similar to Optibond XTR, and was not influenced by type of adhesive, unlike two-step self-etch adhesives.

The impact of chlorhexidine mouth rinse on the bond strength of polycarbonate orthodontic brackets.

PubMed

Hussein, Farouk Ahmed; Hashem, Mohammed Ibrahim; Chalisserry, Elna P; Anil, Sukumaran

2014-11-01

The purpose of the current in-vivo study was to assess the effect of using 0.12% chlorhexidine (CHX) mouth rinse, before bonding, on shear bond strength of polycarbonate brackets bonded with composite adhesive. Eighteen orthodontic patients with a mean age 21.41 ± 1.2 years, who were scheduled to have 2 or more first premolars extracted, were included in this study. Patients were referred for an oral prophylaxis program which included, in part, the use of a mouth rinse. Patients were divided into 2 groups, a test group of 9 patients who used 0.12% CHX gluconate mouth rinse twice daily and a control group of 9 patients who used a mouth rinse without CHX, but with same color. After 1 week, polycarbonate brackets were bonded to first premolars with Transbond XT composite adhesive. Premolars were extracted after 28 days and tested for shear bond strength on a universal testing machine. Student's t-test was used to compare shear bond strengths of both groups. No statistically significant difference was found in bond strengths' values between both groups. The test group (with CHX) has mean shear bond strength of 14.21 ± 2.42 MPa whereas the control group (without CHX) revealed a mean strength of 14.52 ± 2.31 MPa. The use of 0.12% CHX mouth rinse, for one week before bonding, did not affect the shear bond strength of polycarbonate brackets bonded with Transbond composite. Furthermore, these brackets showed clinically acceptable bond strength.

Shear bond strengths of self-etching adhesives to caries-affected dentin on the gingival wall.

PubMed

Koyuturk, Alp Erdin; Sengun, Abdulkadir; Ozer, Fusun; Sener, Yagmur; Gokalp, Alparslan

2006-03-01

The purpose of this study was to evaluate the bonding ability of five current self-etching adhesives to caries-affected dentin on the gingival wall. Seventy extracted human molars with approximal dentin caries were employed in this study. In order to obtain caries-affected dentin on the gingival wall, grinding was performed under running water. Following which, specimens mounted in acrylic blocks and composite resins of the bonding systems were bonded to dentin with plastic rings and then debonded by shear bond strength. With Clearfil SE Bond, bonding to caries-affected dentin showed the highest bond strength. With Optibond Solo Plus Self-Etch, bonding to caries-affected dentin showed higher shear bond strength than AQ Bond, Tyrian SPE & One-Step Plus, and Prompt-L-Pop (p<0.05). Further, the bond strengths of Clearfil SE Bond and Optibond Solo Plus Self-Etch to sound dentin were higher than those of Prompt-L-Pop, AQ Bond, and Tyrian SPE & One-Step Plus (p<0.05). In conclusion, besides micromechanical interlocking through hybrid layer formation, bond strength of self-etch adhesives to dentin may be increased from additional chemical interaction between the functional monomer and residual hydroxyapatite. The results of this study confirmed that differences in bond strength among self-etching adhesives to both caries-affected and sound dentin were due to chemical composition rather than acidity.

IR spectroscopy as a source of data on bond strengths

NASA Astrophysics Data System (ADS)

Finkelshtein, E. I.; Shamsiev, R. S.

2018-02-01

The aim of this work is the estimation of double bond strength, namely Cdbnd O bonds in ketones and aldehydes and Cdbnd C bonds in various compounds. By the breaking of these bonds one or both fragments formed are carbenes, for which experimental data on the enthalpies of formation (ΔHf298) are scarce. Thus for the estimation of ΔHf298 of the corresponding carbenes, the empirical equations were proposed based on different approximations. In addition, a quantum chemical calculations of the ΔHf298 values of carbenes were performed, and the data obtained were compared with experimental values and the results of earlier calculations. Equations for the calculation of Cdbnd O bond strengths of different ketones and aldehydes from the corresponding stretching frequencies ν(Cdbnd O) were derived. Using the proposed equations, the strengths of Cdbnd O bonds of 25 ketones and 12 conjugated aldehydes, as well as Cdbnd C bonds of 13 hydrocarbons and 7 conjugated aldehydes were estimated for the first time. Linear correlations of Cdbnd C and Cdbnd O bond strengths with the bond lengths were established, and the equations permitting the estimation of the double bond strengths and lengths with acceptable accuracy were obtained. Also, the strength of central Cdbnd C bond of stilbene was calculated for the first time. The uncertainty of the strengths of double bonds obtained may be regarded as accurate ±10-15 kJ/mol.

The Effect on Final Bond Strength of Bracket Manipulation Subsequent To Initial Positioning

NASA Astrophysics Data System (ADS)

Beebe, David A.

The shear bond strength of light activated orthodontic adhesives varies according to the composition of the material, placement protocol, and time prior to light curing. Manipulating brackets after their initial placement on a tooth can disrupt the adhesive's polymerization and compromise final bond strength. No previous research has investigated how a specific degree of manipulation, and the amount of time elapsed prior to curing, under specific lighting conditions, affects the orthodontic adhesives shear bond strength. Victory SeriesRTM, MBT prescription, premolar (3M Unitek, Monrovia, CA) orthodontic brackets were bonded using three different adhesives to sixty (60) bicuspids and varying the time after bracket manipulation before curing. The shear bond strength was calculated for each specimen. The brackets were debonded and the same teeth were rebonded with new, identical brackets, using the same protocol and under the same conditions. The results showed a statistically significant difference between the shear bond strength of Transbond XT and Grengloo, with Transbond XT having the highest strength. There was also a statistically significance difference in bond strength between the group cured 30 seconds after manipulation and the groups manipulated at different intervals prior to curing, with the 30 second group having the highest bond strength. This study confirms that various orthodontic adhesives have different bond strengths depending on manipulation and varying times prior to curing each adhesive.

Enamel and dentin bond strength following gaseous ozone application.

PubMed

Cadenaro, Milena; Delise, Chiara; Antoniollo, Francesca; Navarra, Ottavia Chiara; Di Lenarda, Roberto; Breschi, Lorenzo

2009-08-01

To evaluate the effects of gaseous ozone application on enamel and dentin bond strength produced by two self-etching adhesive systems. The shear bond strength test was conducted to assess adhesion on enamel (protocol 1), while the microtensile bond strength test was performed on dentin (protocol 2). Protocol 1: 96 bovine incisors were randomly divided into 4 groups, and enamel surfaces were bonded in accordance with the following treatments: (1E) ozone + Clearfil Protect Bond; (2E) Clearfil Protect Bond (control); (3E) ozone + Xeno III; (4E) Xeno III (control). Ozone gas was applied for 80 s. Shear bond strength was measured with a universal testing machine. Protocol 2: 40 noncarious human molars were selected. Middle/deep dentin was exposed and bonded in accordance with the following treatments: (1D) ozone+Clearfil Protect Bond; (2D) Clearfil Protect Bond (control); (3D) ozone+Xeno III (4D) Xeno III (control). Four-mm-thick buildups were built on the adhesives, then specimens were sectioned in accordance with the nontrimming technique. Specimens were stressed until failure occurred, and failure modes were analyzed. Shear bond and microtensile bond strength data were analyzed using two-way ANOVA and Tukey's post-hoc test. No statistical differences were found between ozone treated specimens and controls, neither on enamel nor on dentin irrespective of the tested adhesive. Clearfil Protect Bond showed higher bond strength to enamel than Xeno III, irrespective of the ozone treatment (p < 0.05). The use of ozone gas to disinfect the cavity before placing a restoration had no influence on immediate enamel and dentin bond strength.

Effects of blood contamination on microtensile bond strength to dentin of three self-etch adhesives.

PubMed

Chang, Seok Woo; Cho, Byeong Hoon; Lim, Ran Yeob; Kyung, Seung Hyun; Park, Dong Sung; Oh, Tae Seok; Yoo, Hyun Mi

2010-01-01

This study evaluated the effects of blood contamination and decontamination methods during different steps of bonding procedures on the microtensile bond strength of two-step self-etch adhesives to dentin. Sixty extracted human molars were ground flat to expose occlusal dentin. The 60 molars were randomly assigned to three groups, each treated with a different two-step self-etch adhesive: Clearfil SE Bond, AdheSE and Tyrian SPE. In turn, these groups were subdivided into five subgroups (n = 20), each treated using different experimental conditions as follows: control group-no contamination; contamination group 1-CG1: primer application/ contamination/primer re-application; contamination group 2-CG2: primer application/contamination/wash/dry/primer re-application; contamination group 3-CG3: primer application/adhesive application/light curing/contamination/ adhesive re-application/light curing; contamina- tion group 4-CG4: primer application/adhesive application/light curing/contamination/wash/ dry/adhesive re-application/light curing. Composite buildup was performed using Z250. After 24 hours of storage in distilled water at 37 degrees C, the bonded specimens were trimmed to an hourglass shape and serially sectioned into slabs with 0.6 mm2 cross-sectional areas. Microtensile bond strengths (MTBS) were assessed for each specimen using a universal testing machine. The data were analyzed by two-way ANOVA followed by a post hoc LSD test. SEM evaluations of the fracture modes were also performed. The contaminated specimens showed lower bond strengths than specimens in the control group (p < 0.05), with the exception of CG1 in the Clearfil SE group and CG2 and CG3 in the Tyrian SPE group. Among the three self-etch adhesives, the Tyrian SPE group exhibited a significantly lower average MTBS compared to the Clearfil SE Bond and AdheSE (p < 0.05) groups. Based on the results of the current study, it was found that blood contamination reduced the MTBS of all three self-etch adhesives to dentin, and water-rinsing was unable to overcome the effects of blood contamination.

Irradiation resistance of silicon carbide joint at light water reactor–relevant temperature

DOE PAGES

Koyanagi, T.; Katoh, Y.; Kiggans, J. O.; ...

2017-03-10

We fabricated and irradiated monolithic silicon carbide (SiC) to SiC plate joints with neutrons at 270–310 °C to 8.7 dpa for SiC. The joining methods included solid state diffusion bonding using titanium and molybdenum interlayers, SiC nanopowder sintering, reaction sintering with a Ti-Si-C system, and hybrid processing of polymer pyrolysis and chemical vapor infiltration (CVI). All the irradiated joints exhibited apparent shear strength of more than 84 MPa on average. Significant irradiation-induced cracking was found in the bonding layers of the Ti and Mo diffusion bonds and Ti-Si-C reaction sintered bond. Furthermore, the SiC-based bonding layers of the SiC nanopowdermore » sintered and hybrid polymer pyrolysis and CVI joints all showed stable microstructure following the irradiation.« less

Effects of Mechanical and Chemical Pretreatments of Zirconia or Fiber Posts on Resin Cement Bonding

PubMed Central

Li, Rui; Zhou, Hui; Wei, Wei; Wang, Chen; Sun, Ying Chun; Gao, Ping

2015-01-01

The bonding strength between resin cement and posts is important for post and core restorations. An important method of improving the bonding strength is the use of various surface pretreatments of the post. In this study, the surfaces of zirconia (fiber) posts were treated by mechanical and/or chemical methods such as sandblasting and silanization. The bonding strength between the zirconia (fiber) post and the resin cement was measured by a push-out method after thermocycling based on the adhesion to Panavia F 2.0 resin cement. The zirconia and fiber posts exhibited different bonding strengths after sandblasting and/or silanization because of the different strengths and chemical structures. The zirconia post showed a high bonding strength of up to 17.1 MPa after a combined treatment of sandblasting and silanization because of the rough surface and covalent bonds at the interface. This effect was also enhanced by using 1,2-bis(trimethoxysilyl)ethane for the formation of a flexible layer at the interface. In contrast, a high bonding strength of 13.9 MPa was obtained for the fiber post treated by silane agents because the sandblasting treatment resulted in damage to the fiber post, as observed by scanning electron microscopy. The results indicated that the improvement in the bonding strength between the post and the resin cement could be controlled by different chemical and/or mechanical treatments. Enhanced bonding strength depended on covalent bonding and the surface roughness. A zirconia post with high bonding strength could potentially be used for the restoration of teeth in the future. PMID:26066349

Bond strength of etch-and-rinse and self-etch adhesive systems to enamel and dentin irradiated with a novel CO2 9.3 μm short-pulsed laser for dental restorative procedures.

PubMed

Rechmann, Peter; Bartolome, N; Kinsel, R; Vaderhobli, R; Rechmann, B M T

2017-12-01

The objective of this study was to evaluate the influence of CO 2 9.3 μm short-pulsed laser irradiation on the shear bond strength of composite resin to enamel and dentin. Two hundred enamel and 210 dentin samples were irradiated with a 9.3 µm carbon dioxide laser (Solea, Convergent Dental, Inc., Natick, MA) with energies which either enhanced caries resistance or were effective for ablation. OptiBond Solo Plus [OptiBondTE] (Kerr Corporation, Orange, CA) and Peak Universal Bond light-cured adhesive [PeakTE] (Ultradent Products, South Jordan, UT) were used. In addition, Scotchbond Universal [ScotchbondSE] (3M ESPE, St. Paul, MN) and Peak SE self-etching primer with Peak Universal Bond light-cured adhesive [PeakSE] (Ultradent Products) were tested. Clearfil APX (Kuraray, New York, NY) was bonded to the samples. After 24 h, a single plane shear bond test was performed. Using the caries preventive setting on enamel resulted in increased shear bond strength for all bonding agents except for self-etch PeakSE. The highest overall bond strength was seen with PeakTE (41.29 ± 6.04 MPa). Etch-and-rinse systems achieved higher bond strength values to ablated enamel than the self-etch systems did. PeakTE showed the highest shear bond strength with 35.22 ± 4.40 MPa. OptiBondTE reached 93.8% of its control value. The self-etch system PeakSE presented significantly lower bond strength. The shear bond strength to dentin ranged between 19.15 ± 3.49 MPa for OptiBondTE and 43.94 ± 6.47 MPa for PeakSE. Etch-and-rinse systems had consistently higher bond strength to CO 2 9.3 µm laser-ablated enamel. Using the maximum recommended energy for dentin ablation, the self-etch system PeakSE reached the highest bond strength (43.9 ± 6.5 MPa).

The effects of dentin and intaglio indirect ceramic optimized polymer restoration surface treatment on the shear bond strength of resin cement

NASA Astrophysics Data System (ADS)

Puspitarini, A.; Suprastiwi, E.; Usman, M.

2017-08-01

Ceramic optimized polymer (ceromer) bonds to the tooth substrate through resin cements. The bond strength between dentin, resin cement, and ceromer depends on the applied surface treatment. To analyze the effects of dentin and intaglio ceromer surface treatment on the shear bond strength self-adhesive resin cement. Forty-five dentin premolar and ceromer specimens were bonded with resin cement and divided into three groups as follows: in group 1, no treatment was applied; in group 2, dentin surface treatment was carried out with acid etching and a bonding agent; and in group 3, dentin surface treatment was carried out with acid etching, a bonding agent, and intaglio ceromer surface treatment with etching and silane. All specimens were incubated at 37 °C for 24 hours, and the shear bond strength was measured using a universal testing machine. Group 3 showed the highest shear bond strength, followed by group 2. The surface treatment of dentin and intaglio ceromer showed significantly improved shear bond strength in the group comparison. Dentin and intaglio ceromer surface treatment can improved the shear bond strength self-adhesive resin cement.

Effect of layered manufacturing techniques, alloy powders, and layer thickness on metal-ceramic bond strength.

PubMed

Ekren, Orhun; Ozkomur, Ahmet; Ucar, Yurdanur

2018-03-01

Direct metal laser sintering (DMLS) and direct metal laser melting (DMLM) have become popular for fabricating the metal frameworks of metal-ceramic restorations. How the type of layered manufacturing device, layer thickness, and alloy powder may affect the bond strength of ceramic to metal substructure is unclear. The purpose of this in vitro study was to evaluate the bond strength of dental porcelain to metal frameworks fabricated using different layered manufacturing techniques (DMLS and DMLM), Co-Cr alloy powders, and layer thicknesses and to evaluate whether a correlation exists between the bond strength and the number of ceramic remnants on the metal surface. A total of 75 bar-shaped metal specimens (n=15) were fabricated using either DMLS or DMLM. The powder alloys used were Keramit NP-S and EOS-Cobalt-Chrome SP-2 with layer thicknesses of 20 μm and 30 μm. After ceramic application, the metal-ceramic bond strength was evaluated with a 3-point-bend test. Three-way ANOVA followed by the Tukey honest significance difference test were used for statistical analysis (α=.05). De-bonding surface microstructure was observed with scanning electron microscopy. Energy dispersive spectroscopy analysis was conducted to evaluate the correlation between ceramic remnants on the metal surface and bond strength values. The mean bond strength value of DMLS was significantly higher than that of DMLM. While no statistically significant difference was found between layer thicknesses, alloy powders closely affected bond strength. Statistical comparisons revealed that the highest bond strength could be achieved with DMLS-Cobalt-Chrome SP2-20μm, and the lowest bond strength was observed in DMLS-Keramit NP-S-20μm (P≤.05). No correlation was found between porcelain remnants on the metal surface and bond strength values. The layered manufacturing device and the alloy powders evaluated in the current study closely affected the bond strength of dental porcelain to a metal framework. However, layer thickness did not affect the bond strength. Copyright © 2017 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

In vitro comparison of the tensile bond strength of denture adhesives on denture bases.

PubMed

Kore, Doris R; Kattadiyil, Mathew T; Hall, Dan B; Bahjri, Khaled

2013-12-01

With several denture adhesives available, it is important for dentists to make appropriate patient recommendations. The purpose of this study was to evaluate the tensile bond strength of denture adhesives on denture base materials at time intervals of up to 24 hours. Fixodent, Super Poligrip, Effergrip, and SeaBond denture adhesives were tested with 3 denture base materials: 2 heat-polymerized (Lucitone 199 and SR Ivocap) and 1 visible-light-polymerized (shade-stable Eclipse). Artificial saliva with mucin was used as a control. Tensile bond strength was tested in accordance with American Dental Association specifications at 5 minutes, 3 hours, 6 hours, 12 hours, and 24 hours after applying the adhesive. Maximum forces before failure were recorded in megapascals (MPa), and the data were subjected to a 2-way analysis of variance (α=.05). All 4 adhesives had greater tensile bond strength than the control. Fixodent, Super Poligrip, and SeaBond had higher tensile bond strength values than Effergrip. All adhesives had the greatest tensile bond strength at 5 minutes and the least at 24 hours. The 3 denture bases produced significantly different results with each adhesive (P<.001). Lucitone 199 with the adhesives had the greatest tensile bond strength, followed by Ivocap and Eclipse. All 4 adhesives had greater tensile bond strength than the control, and all 4 adhesives were strongest at the 5-minute interval. On all 3 types of denture bases, Effergrip produced significantly lower tensile bond strength, and Fixodent, Super Poligrip, and SeaBond produced significantly higher tensile bond strength. At 24 hours, the adhesive-base combinations with the highest tensile bond strength were Fixodent on Lucitone 199, Fixodent on Eclipse, Fixodent on Ivocap, and Super Poligrip on Ivocap. Copyright © 2013 Editorial Council for the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.

Bond strength and microleakage of current dentin adhesives.

PubMed

Fortin, D; Swift, E J; Denehy, G E; Reinhardt, J W

1994-07-01

The purpose of this in vitro study was to evaluate shear bond strengths and microleakage of seven current-generation dentin adhesive systems. Standard box-type Class V cavity preparations were made at the cemento-enamel junction on the buccal surfaces of eighty extracted human molars. These preparations were restored using a microfill composite following application of either All-Bond 2 (Bisco), Clearfil Liner Bond (Kuraray), Gluma 2000 (Miles), Imperva Bond (Shofu), OptiBond (Kerr), Prisma Universal Bond 3 (Caulk), Scotchbond Multi-Purpose (3M), or Scotchbond Dual-Cure (3M) (control). Lingual dentin of these same teeth was exposed and polished to 600-grit. Adhesives were applied and composite was bonded to the dentin using a gelatin capsule technique. Specimens were thermocycled 500 times. Shear bond strengths were determined using a universal testing machine, and microleakage was evaluated using a standard silver nitrate staining technique. Clearfill Liner Bond and OptiBond, adhesive systems that include low-viscosity, low-modulus intermediate resins, had the highest shear bond strengths (13.3 +/- 2.3 MPa and 12.9 +/- 1.5 MPa, respectively). Along with Prisma Universal Bond 3, they also had the least microleakage at dentin margins of Class V restorations. No statistically significant correlation between shear bond strength and microleakage was observed in this study. Adhesive systems that include a low-viscosity intermediate resin produced the high bond strengths and low microleakage. Similarly, two materials with bond strengths in the intermediate range had significantly increased microleakage, and one material with a bond strength in the low end of the spectrum exhibited microleakage that was statistically greater. Thus, despite the lack of statistical correlation, there were observable trends.

Comparison of the tensile bond strength of high-noble, noble, and base metal alloys bonded to enamel.

PubMed

Sen, D; Nayir, E; Pamuk, S

2000-11-01

Although the bond strengths of various resin composite luting materials have been reported in the literature, the evaluation of these systems with various cast alloys of different compositions has not been completely clarified. To evaluate the tensile bond strength of sandblasted high-noble, noble, and base metal alloys bonded to etched enamel by 2 different bonding agents of different chemical composition: Panavia-Ex (BIS-GMA) and Super-Bond (4-META acrylic). Flat enamel surfaces were prepared on buccal surfaces of 60 extracted noncarious human incisors. Teeth were divided into 3 groups of 20 each. Twenty circular disks of 5 mm diameter were prepared for casting for each group. Group I was cast with a high-noble, group II with a noble, and group III with a base metal alloy. The surfaces of the disks were sandblasted with 250 microm Al(2)O(3). Ten disks of each group were bonded to exposed enamel surfaces with Super-Bond and 10 disks with Panavia-Ex as recommended by the manufacturer. The tensile bond strength was measured with an Instron universal testing machine with a crosshead speed of 0.5 mm/min until failure occurred. Two-way ANOVA was used to evaluate the results. The differences in bond strengths of Super-Bond and Panavia-Ex with different alloys were not significant. The highest bond strengths were obtained in base metal alloys, followed by noble and high-noble alloys. These results were significant. Panavia-Ex and Super-Bond exhibited comparable tensile bond strengths. For both luting agents, the highest bond strengths were achieved with base metal alloys and the lowest with high-noble alloys.

Bond strength of self-etch adhesives after saliva contamination at different application steps.

PubMed

Cobanoglu, N; Unlu, N; Ozer, F F; Blatz, M B

2013-01-01

This study evaluated and compared the effect of saliva contamination and possible decontamination methods on bond strengths of two self-etching adhesive systems (Clearfil SE Bond [CSE], Optibond Solo Plus SE [OSE]). Flat occlusal dentin surfaces were created on 180 extracted human molar teeth. The two bonding systems and corresponding composite resins (Clearfil AP-X, Kerr Point 4) were bonded to the dentin under six surface conditions (n=15/group): group 1 (control): primer/bonding/composite; group 2: saliva/drying/primer/bonding/composite; group 3: primer/saliva/rinsing/drying/primer/bonding/composite; group 4: primer/saliva/rinsing/drying/bonding/composite; group 5: primer/bonding (cured)/saliva/rinsing/drying/primer/bonding/composite; group 6: primer/bonding (cured)/saliva/removing contaminated layer with a bur/rinsing/drying/primer/bonding/composite. Shear bond strength was tested after specimens were stored in distilled water at 37°C for 24 hours. One-way analysis of variance and Tukey post hoc tests were used for statistical analyses. For CSE, groups 2, 3, and 4 and for OSE, groups 6, 2, and 4 showed significantly lower bond strengths than the control group (p<0.05). CSE groups 5 and 6 and OSE groups 3 and 5 revealed bond strengths similar to the control. When saliva contamination occurred after light polymerization of the bonding agent, repeating the bonding procedure recovered the bonding capacity of both self-etch adhesives. However, saliva contamination before or after primer application negatively affected their bond strength.

Innovations in bonding to zirconia based ceramics: Part III. Phosphate monomer resin cements.

PubMed

Mirmohammadi, Hesam; Aboushelib, Moustafa N M; Salameh, Ziad; Feilzer, Albert J; Kleverlaan, Cornelis J

2010-08-01

To compare the bond strength values and the ranking order of three phosphate monomer containing resin cements using microtensile (microTBS) and microshear (microSBS) bond strength tests. Zirconia discs (Procera Zirconia) were bonded to resin composite discs (Filtek Z250) using three different cements (Panavia F 2.0, RelyX UniCem, and Multilink). Two bond strength tests were used to determine zirconia resin bond strength; microtensile bond strength test (microTBS) and microshear bond strength test (microSBS). Ten specimens were tested for each group (n=10). Two-way analysis of variance (ANOVA) was used to analyze the data (alpha=0.05). There were statistical significant differences in bond strength values and in the ranking order obtained using the two test methods. microTBS reported significant differences in bond strength values, whereas microSBS failed to detect such effect. Both Multilink and Panavia demonstrated basically cohesive failure in the resin cement while RelyX UniCem demonstrated interfacial failure. Based on the findings of this study, the data obtained using either microTBS or microSBS could not be directly compared. microTBS was more sensitive to material differences compared to microSBS which failed to detect such differences. Copyright 2010 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Mechanical and bond strength properties of light-cured and chemically cured glass ionomer cements.

PubMed

McCarthy, M F; Hondrum, S O

1994-02-01

The purpose of this study was to evaluate the mechanical and bond strength properties of a commercially available light-cured glass ionomer cement and of a chemically cured glass ionomer cement. Sixty recently extracted human molars were randomly divided into six equal groups, and the bond strengths of the two cement types were evaluated at 1 hour, 24 hours, and 7 days. Stainless steel lingual buttons were bonded to prepared enamel surfaces, and the samples were placed in a water bath at 37 degrees C until testing. The shear bond strength of each sample was determined with a universal testing instrument. The mechanical strength properties of the two cements were then evaluated. The transverse flexural strength, compressive strength, rigidity, and diametral tensile strength were tested for each cement at 1 hour, 24 hours, and 7 days. The results of the mechanical property strength tests were then compared with the results of the bond strength tests.(ABSTRACT TRUNCATED AT 250 WORDS)

Comparison of the effect of different surface treatments on the bond strength of different cements with nickel chromium metal alloy: An in vitro study

PubMed Central

Kapoor, Saumya; Balakrishnan, Dhanasekar

2017-01-01

Background For success of any indirect metal restoration, a strong bond between cement and the intaglio surface of metal is imperative. The aim of this study is to evaluate and compare the effect of different surface treatment on the tensile and shear bond strength of different cements with nickel–chromium alloy. Material and Methods 120 premolars were sectioned horizontally parallel to the occlusal surface to expose the dentin. Wax patterns were fabricated for individual tooth followed by casting them in nickel chromium alloy. 60 samples were tested for tensile bond strength, and the remaining 60 for shear bond strength. The samples were divided into three groups (of 20 samples each) as per the following surface treatment: oxidation only, oxidation and sandblasting, or oxidation, sandblasting followed by application of alloy primer. Each group was subdivided into 2 subgroups of 10 samples each, according to the bonding cement i.e RM-GIC and resin cement. Samples were subjected to thermocycling procedure followed by evaluation of bond strength. Results Two-way analyses of variance (ANOVA) was performed to compare the means of tensile and shear bond strength across type of surface treatment and cement, followed by post hoc parametric analysis. For all tests ‘p’ value of less than 0.05 was considered statistically significant. Conclusions The surface treatment of oxidation and sandblasting followed by application of alloy primer offered the maximum tensile and shear bond strength for both RM GIC and resin cement. Resin cement exhibited greater tensile and shear bond strength than RM-GIC for all the three surface treatment methods. Key words:Resin cement, resin modified glass ionomer cement, oxidation, sandblasting, alloy primer, tensile bond strength, shear bond strength, universal testing machine. PMID:28828160

Determination of high-strength materials diamond grinding rational modes

NASA Astrophysics Data System (ADS)

Arkhipov, P. V.; Lobanov, D. V.; Rychkov, D. A.; Yanyushkin, A. S.

2018-03-01

The analysis of methods of high-strength materials abrasive processing is carried out. This method made it possible to determine the necessary directions and prospects for the development of shaping combined methods. The need to use metal bonded diamond abrasive tools in combination with a different kind of energy is noted to improve the processing efficiency and reduce the complexity of operations. The complex of experimental research on revealing the importance of mechanical and electrical components of cutting regimes, on the cutting ability of diamond tools, as well as the need to reduce the specific consumption of an abrasive wheel as one of the important economic indicators of the processing process is performed. It is established that combined diamond grinding with simultaneous continuous correction of the abrasive wheel contributes to an increase in the cutting ability of metal bonded diamond abrasive tools when processing high-strength materials by an average of 30% compared to diamond grinding. Particular recommendations on the designation of technological factors are developed depending on specific production problems.

The influence of main bar corrosion on bond strength in selfcompacting concrete

NASA Astrophysics Data System (ADS)

Ayop, S. S.; Emhemed, A. N. K.; Jamaluddin, N.; Sadikin, A.

2017-11-01

The experimental study was conducted to determine the influence of main bar corrosion on bond strength in self-compacting concrete (SCC). A total 16 tension pullout tests specimens reinforced with 10 mm and 14 mm diameter bar were used for the bond strength test. The properties of SCC were determined from the slump flow, T50cm, V-funnel and L box test. Reinforcing bars in the concrete were submitted to impressed current to accelerate the corrosion of the bar. It was found that the relationship between bond strength and concrete strength in un-corroded specimens differed from that of corroded specimens set in high-strength concrete because of brittleness in the corroded specimens, which caused a sudden loss of bond strength. The results revealed that specimens of un-corroded and corroded showed a higher percentage of bond strength degradation during the pullout tests.

Composite bonding to stainless steel crowns using a new universal bonding and single-bottle systems.

PubMed

Hattan, Mohammad Ali; Pani, Sharat Chandra; Alomari, Mohammad

2013-01-01

Aim. The aim of this study is to evaluate the shear bond strength of nanocomposite to stainless steel crowns using a new universal bonding system. Material and Methods. Eighty (80) stainless steel crowns (SSCs) were divided into four groups (20 each). Packable nanocomposite was bonded to the lingual surface of the crowns in the following methods: Group A without adhesive (control group), Group B using a new universal adhesive system (Scotchbond Universal Adhesive, 3M ESPE, Seefeld, Germany), and Group C and Group D using two different brands of single-bottle adhesive systems. Shear bond strengths were calculated and the types of failure also were recorded. Results. The shear strength of Group B was significantly greater than that of other groups. No significant differences were found between the shear bond strengths of Groups C and D. The control group had significantly lower shear bond strength (P < 0.05) to composite than the groups that utilized bonding agents. Conclusion. Composites bonding to stainless steel crowns using the new universal bonding agent (Scotchbond Universal Adhesive, 3M ESPE, Seefeld, Germany) show significantly greater shear bond strengths and fewer adhesive failures when compared to traditional single-bottle systems.

Shear bond strength between an indirect composite layering material and feldspathic porcelain-coated zirconia ceramics.

PubMed

Fushiki, Ryosuke; Komine, Futoshi; Blatz, Markus B; Koizuka, Mai; Taguchi, Kohei; Matsumura, Hideo

2012-10-01

This study aims to evaluate the effect of both feldspathic porcelain coating of zirconia frameworks and priming agents on shear bond strength between an indirect composite material and zirconia frameworks. A total of 462 airborne-particle-abraded zirconia disks were divided into three groups: untreated disks (ZR-AB), airborne-particle-abraded zirconia disks coated with feldspathic porcelain, (ZR-PO-AB), and hydrofluoric acid-etched zirconia disks coated with feldspathic porcelain (ZR-PO-HF). Indirect composite (Estenia C&B) was bonded to zirconia specimens with no (CON) or one of four priming agents--Clearfil Photo Bond (CPB), Clearfil Photo Bond with Clearfil Porcelain Bond Activator (CPB + activator), Estenia Opaque primer, or Porcelain Liner M Liquid B (PLB)--with or without an opaque material (Estenia C&B Opaque). All specimens were tested for shear bond strength before and after 20,000 thermocycles. The Steel-Dwass test and Mann-Whitney U test were used to compare shear bond strength. In ZR-AB specimens, the initial bond strength of the CPB and CPB + Activator groups was significantly higher as compared with the other three groups (P < 0.05), whereas the PLB and CPB + Activator groups had the highest pre- and post-thermocycling bond strengths in ZR-PO-AB and ZR-PO-HF specimens. Among CON disks without opaque material, bond strength was significantly lower in ZR-AB specimens than in ZR-PO-AB and ZR-PO-HF specimens (P < 0.05). Feldspathic porcelain coating of a Katana zirconia framework enhanced the bond strength of Estenia C&B indirect composite to zirconia independent of surface treatment. The use of a silane coupling agent and opaque material yields durable bond strength between the indirect composite and feldspathic-porcelain-coated zirconia. The results of the present study suggest that feldspathic porcelain coating of zirconia frameworks is an effective method to obtain clinically acceptable bond strengths of a layering indirect composite material to a zirconia framework.

Post-thermocycling shear bond strength of a gingiva-colored indirect composite layering material to three implant framework materials.

PubMed

Komine, Futoshi; Koizuka, Mai; Fushiki, Ryosuke; Taguchi, Kohei; Kamio, Shingo; Matsumura, Hideo

2013-09-01

To evaluate shear bond strength of a gingiva-colored indirect composite to three implant framework materials, before and after thermocycling, and verify the effect of surface pre-treatment for each framework. Commercially pure titanium (CP-Ti), American Dental Association (ADA) type 4 casting gold alloy (Type IV) and zirconia ceramics (Zirconia) were assessed. For each substrate, 96 disks were divided into six groups and primed with one of the following primers: Alloy Primer (ALP), Clearfil Photo Bond (CPB), Clearfil Photo Bond with Clearfil Porcelain Bond Activator (CPB+Activator), Estenia Opaque Primer (EOP), Metal Link (MLP) and V-Primer (VPR). The specimens were then bonded to a gingiva-colored indirect composite (Ceramage Concentrate GUM-D). Shear bond strengths were measured at 0 and 20 000 thermocycles and data were analyzed with the Steel-Dwass test and Mann-Whitney U-test. Shear bond strengths were significantly lower after thermocycling, with the exception of Type IV specimens primed with CPB (p = 0.092) or MLP (p = 0.112). For CP-Ti and Zirconia specimens, priming with CPB or CPB+Activator produced significantly higher bond strengths at 0 and 20 000 thermocycles, as compared with the other groups. For Type IV specimens, priming with ALP or MLP produced higher bond strengths at 0 and 20 000 thermocycles. Shear bond strength of a gingiva-colored indirect composite to CP-Ti, gold alloy and zirconia ceramics was generally lower after thermocycling. Application of a hydrophobic phosphate monomer and polymerization initiator was effective in maintaining bond strength of CP-Ti and zirconia ceramics. Combined use of a thione monomer and phosphoric monomer enhanced the durable bond strength of gold alloy.

Temporal heating profile influence on the immediate bond strength following laser tissue soldering.

PubMed

Rabi, Yaron; Katzir, Abraham

2010-07-01

Bonding of tissues by laser heating is considered as a future alternative to sutures and staples. Increasing the post-operative bond strength remains a challenging issue for laser tissue bonding, especially in organs that have to sustain considerable tension or pressure. In this study, we investigated the influence of different temporal heating profiles on the strength of soldered incisions. The thermal damage following each heating procedure was quantified, in order to assess the effect of each heating profile on the thermal damage. Incisions in porcine bowel tissue strips (1 cmx4 cm) were soldered, using a 44% liquid albumin mixed with indocyanine green and a temperature controlled laser (830 nm) tissue bonding system. Heating was done either with a linear or a step temporal heating profile. The incisions were bonded by soldering at three points, separated by 2 mm. Set-point temperatures of T(set) = 60, 70, 80, 90, 100, 110, 150 degrees C and dwell times of t(d) = 10, 20, 30, 40 seconds were investigated. The bond strength was measured immediately following each soldering by applying a gradually increased tension on the tissue edges until the bond break. Bonds formed by linear heating were stronger than the ones formed by step heating: at T(set) = 80 degrees C the bonds were 40% stronger and at T(set) = 90 degrees C the bonds strength was nearly doubled. The bond strength difference between the heating methods was larger as T(set) increased. Linear heating produced stronger bonds than step heating. The difference in the bond strength was more pronounced at high set-point temperatures and short dwell times. The bond strength could be increased with either higher set-point temperature or a longer dwell time.

Shear bond strength of a denture base acrylic resin and gingiva-colored indirect composite material to zirconia ceramics.

PubMed

Kubochi, Kei; Komine, Futoshi; Fushiki, Ryosuke; Yagawa, Shogo; Mori, Serina; Matsumura, Hideo

2017-04-01

To evaluate the shear bond strengths of two gingiva-colored materials (an indirect composite material and a denture base acrylic resin) to zirconia ceramics and determine the effects of surface treatment with various priming agents. A gingiva-colored indirect composite material (CER) or denture base acrylic resin (PAL) was bonded to zirconia disks with unpriming (UP) or one of seven priming agents (n=11 each), namely, Alloy Primer (ALP), Clearfil Photo Bond (CPB), Clearfil Photo Bond with Clearfil Porcelain Bond Activator (CPB+Act), Metal Link (MEL), Meta Fast Bonding Liner (MFB), MR. bond (MRB), and V-Primer (VPR). Shear bond strength was determined before and after 5000 thermocycles. The data were analyzed with the Kruskal-Wallis test and Steel-Dwass test. The mean pre-/post-thermalcycling bond strengths were 1.0-14.1MPa/0.1-12.1MPa for the CER specimen and 0.9-30.2MPa/0.1-11.1MPa for the PAL specimen. For the CER specimen, the ALP, CPB, and CPB+Act groups had significantly higher bond strengths among the eight groups, at both 0 and 5000 thermocycles. For the PAL specimen, shear bond strength was significantly lower after thermalcycling in all groups tested. After 5000 thermocycles, bond strengths were significantly higher in the CPB and CPB+Act groups than in the other groups. For the PAL specimens, bond strengths were significantly lower after thermalcycling in all groups tested. The MDP functional monomer improved bonding of a gingiva-colored indirect composite material and denture base acrylic resin to zirconia ceramics. Copyright © 2016 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

Bonding measurement -Strength and fracture mechanics approaches.

PubMed

Anunmana, Chuchai; Wansom, Wiroj

2017-07-26

This study investigated the effect of cross-sectional areas on interfacial fracture toughness and bond strength of bilayered dental ceramics. Zirconia core ceramics were veneered and cut to produce specimens with three different cross-sectional areas. Additionally, monolithic specimens of glass veneer were also prepared. The specimens were tested in tension until fracture at the interface and reported as bond strength. Fracture surfaces were observed, and the apparent interfacial toughness was determined from critical crack size and failure stress. The results showed that cross-sectional area had no effect on the interfacial toughness whereas such factor had a significant effect on interfacial bond strength. The study revealed that cross-sectional area had no effect on the interfacial toughness, but had a significant effect on interfacial bond strength. The interfacial toughness may be a more reliable indicator for interfacial bond quality than interfacial bond strength.

Influence of dentin pretreatment on bond strength of universal adhesives.

PubMed

Poggio, Claudio; Beltrami, Riccardo; Colombo, Marco; Chiesa, Marco; Scribante, Andrea

2017-01-01

Objective: The purpose of the present study was to compare bond strength of different universal adhesives under three different testing conditions: when no pretreatment was applied, after 37% phosphoric acid etching and after glycine application. Materials and methods: One hundred and fifty bovine permanent mandibular incisors were used as a substitute for human teeth. Five different universal adhesives were tested: Futurabond M+, Scotchbond Universal, Clearfil Universal Bond, G-Premio BOND, Peak Universal Bond. The adhesive systems were applied following each manufacturer's instructions. The teeth were randomly assigned to three different dentin surface pretreatments: no pretreatment agent (control), 37% phosphoric acid etching, glycine pretreatment. The specimens were placed in a universal testing machine in order to measure and compare bond strength values. Results: The Kruskal-Wallis analysis of variance and the Mann-Whitney test were applied to assess significant differences among the groups. Dentin pretreatments provided different bond strength values for the adhesives tested, while similar values were registered in groups without dentin pretreatment. Conclusions: In the present report, dentin surface pretreatment did not provide significant differences in shear bond strength values of almost all groups. Acid pretreatment lowered bond strength values of Futurabond and Peak Universal Adhesives, whereas glycine pretreatment increased bond strength values of G Praemio Bond adhesive system.

Influence of dentin pretreatment on bond strength of universal adhesives

PubMed Central

Poggio, Claudio; Beltrami, Riccardo; Colombo, Marco; Chiesa, Marco; Scribante, Andrea

2017-01-01

Abstract Objective: The purpose of the present study was to compare bond strength of different universal adhesives under three different testing conditions: when no pretreatment was applied, after 37% phosphoric acid etching and after glycine application. Materials and methods: One hundred and fifty bovine permanent mandibular incisors were used as a substitute for human teeth. Five different universal adhesives were tested: Futurabond M+, Scotchbond Universal, Clearfil Universal Bond, G-Premio BOND, Peak Universal Bond. The adhesive systems were applied following each manufacturer’s instructions. The teeth were randomly assigned to three different dentin surface pretreatments: no pretreatment agent (control), 37% phosphoric acid etching, glycine pretreatment. The specimens were placed in a universal testing machine in order to measure and compare bond strength values. Results: The Kruskal–Wallis analysis of variance and the Mann–Whitney test were applied to assess significant differences among the groups. Dentin pretreatments provided different bond strength values for the adhesives tested, while similar values were registered in groups without dentin pretreatment. Conclusions: In the present report, dentin surface pretreatment did not provide significant differences in shear bond strength values of almost all groups. Acid pretreatment lowered bond strength values of Futurabond and Peak Universal Adhesives, whereas glycine pretreatment increased bond strength values of G Praemio Bond adhesive system. PMID:28642929

[Evaluation of shear bond strengths of self-etching and total-etching dental adhesives to enamel and dentin].

PubMed

Yu, Ling; Liu, Jing-Ming; Wang, Xiao-Yan; Gao, Xue-Jun

2009-03-01

To evaluate the shear bond strengths of four dental adhesives in vitro. The facial surfaces of 20 human maxillary incisors were prepared to expose fresh enamel and randomly divided into four groups, in each group 5 teeth were bonded with one adhesives: group A (Clearfil Protect Bond, self-etching two steps), group B (Adper( Prompt, self-etching one step), group C (SwissTEC SL Bond, total-etching two steps), group D (Single Bond, total-etching two steps). Shear bond strengths were determined using an universal testing machine after being stored in distilled water for 24 h at 37 degrees C. The bond strengths to enamel and dentin were (25.33 +/- 2.84) and (26.07 +/- 5.56) MPa in group A, (17.08 +/- 5.13) and (17.93 +/- 4.70) MPa in group B, (33.14 +/- 6.05) and (41.92 +/- 6.25) MPa in group C, (22.51 +/- 6.25) and (21.45 +/- 7.34) MPa in group D. Group C showed the highest and group B the lowest shear bond strength to enamel and dentin among the four groups. The two-step self-etching adhesive showed comparable shear bond strength to some of the total-etching adhesives and higher shear bond strength than one-step self-etching adhesive.

Effect of universal adhesive etching modes on bond strength to dual-polymerizing composite resins.

PubMed

Michaud, Pierre-Luc; Brown, Matthew

2018-04-01

Information is lacking as to the effect on bond strength of the etching modes of universal adhesives when they are used to bond dual-polymerizing composite resins to dentin. The purpose of this in vitro study was to investigate the bonding of dual-polymerizing foundation composite resins to dentin when universal bonding agents are used in self-etch or etch-and-rinse modes. Sixty caries-free, extracted third molar teeth were sectioned transversely in the apical third of the crown and allocated to 12 groups (n=5). Three different bonding agents (Scotchbond Universal, OptiBond XTR, All-Bond Universal) were used to bond 2 different dual-polymerizing composite resins (CompCore AF or CoreFlo DC) to dentin, using 2 different etching approaches (etch-and-rinse or self-etch). The specimens were sectioned into sticks (1×1×8 mm) with a precision saw. The bond strength of the specimens was tested under microtensile force at a crosshead speed of 0.5 mm/min. The data were analyzed using a 3-way ANOVA, a Games-Howell post hoc comparisons model, and Student t tests with Bonferroni corrections (α=.05). In the overall model, the composite resin used had no effect on bond strength (P=.830). The etching protocol by itself also did not have a significant effect (P=.059), although a trend was present. The bonding agent, however, did have an effect (P<.001) on bond strength. Also, a significant interaction effect was found for the bonding agent and etching protocol on bond strength (P<.001). The etching protocol influenced the bond strength when Scotchbond Universal (P<.008) and All-Bond Universal (P<.004) were used but not when OptiBond XTR was used (P=1.00). A self-etch protocol provided significantly higher bond strength when Scotchbond Universal was used, whereas with All-Bond Universal, an etch-and-rinse protocol, provided higher bond strength. When universal bonding agents were used to secure dual-polymerizing composite resins to dentin, no single etching protocol is better than another. Depending on which bonding agent is being used, one etching mode may perform better. Copyright © 2017 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Adhesion of resin composite core materials to dentin.

PubMed

O'Keefe, K L; Powers, J M

2001-01-01

This study determined (1) the effect of polymerization mode of resin composite core materials and dental adhesives on the bond strength to dentin, and (2) if dental adhesives perform as well to dentin etched with phosphoric acid as to dentin etched with self-etching primer. Human third molars were sectioned 2 mm from the highest pulp horn and polished. Three core materials (Fluorocore [dual cured], Core Paste [self-cured], and Clearfil Photo Core [light cured]) and two adhesives (Prime & Bond NT Dual Cure and Clearfil SE Bond [light cured]) were bonded to dentin using two dentin etching conditions. After storage, specimens were debonded in microtension and bond strengths were calculated. Scanning electron micrographs of representative bonding interfaces were analyzed. Analysis showed differences among core materials, adhesives, and etching conditions. Among core materials, dual-cured Fluorocore had the highest bond strengths. There were incompatibilities between self-cured Core Paste and Prime & Bond NT in both etched (0 MPa) and nonetched (3.0 MPa) dentin. Among adhesives, in most cases Clearfil SE Bond had higher bond strengths than Prime & Bond NT and bond strengths were higher to self-etched than to phosphoric acid-etched dentin. Scanning electron micrographs did not show a relationship between resin tags and bond strengths. There were incompatibilities between a self-cured core material and a dual-cured adhesive. All other combinations of core materials and adhesives produced strong in vitro bond strengths both in the self-etched and phosphoric acid-etched conditions.

A Comparative Evaluation of the Effect of Bonding Agent on the Tensile Bond Strength of Two Pit and Fissure Sealants Using Invasive and Non-invasive Techniques: An in-vitro Study.

PubMed

Singh, Shamsher; Adlakha, Vivek; Babaji, Prashant; Chandna, Preetika; Thomas, Abi M; Chopra, Saroj

2013-10-01

Newer technologies and the development of pit and fissure sealants have shifted the treatment philosophy from 'drill and fill' to that of 'seal and heal'. The purpose of this in-vitro study was to evaluate the effects of bonding agents on the tensile bond strengths of two pit and fissure sealants by using invasive and non-invasive techniques. One hundred and twenty bicuspids were collected and teeth were divided into two groups: Group-I (Clinpro) and Group-II (Conseal f) with 60 teeth in each group. For evaluating tensile bond strengths, occlusal surfaces of all the teeth were flattened by reducing buccal and lingual cusps without disturbing fissures. Standardised polyvinyl tube was bonded to occlusal surfaces with respective materials. Sealants were applied, with or without bonding agents, in increments and they were light cured. Tensile bond strengths were determined by using Universal Testing Machine. Data were then statistically analysed by using Student t-test for comparison. A statistically significant difference was found in tensile bond strength in invasive with bonding agent group than in non-invasive with bonding agent group. This study revealed that invasive techniques increase the tensile bond strengths of sealants as compared to non- invasive techniques and that the use of a bonding agent as an intermediate layer between the tooth and fissure sealant is beneficial for increasing the bond strength.

Fluxless eutectic bonding of GaAs-on-Si by using Ag/Sn solder

NASA Astrophysics Data System (ADS)

Eo, Sung-Hwa; Kim, Dae-Seon; Jeong, Ho-Jung; Jang, Jae-Hyung

2013-11-01

Fluxless GaAs-on-Si wafer bonding using Ag/Sn solder was investigated to realize uniform and void-free heterogeneous material integration. The effects of the diffusion barrier, Ag/Sn thickness, and Ar plasma treatment were studied to achieve the optimal fluxless bonding process. Pt on a GaAs wafer and Mo on a Si wafer act as diffusion barriers by preventing the flow of Ag/Sn solder into both the wafers. The bonding strength is closely related to the Ag/Sn thickness and Ar plasma treatment. A shear strength test was carried out to investigate the bonding strength. Under identical bonding conditions, the Ag/Sn thickness was optimized to achieve higher bonding strength and to avoid the formation of voids due to thermal stress. An Ar plasma pretreatment process improved the bonding strength because the Ar plasma removed carbon contaminants and metal-oxide bonds from the metal surface.

In vitro Comparative Evaluation of Tensile Bond Strength of 6(th), 7(th) and 8(th) Generation Dentin Bonding Agents.

PubMed

Kamble, Suresh S; Kandasamy, Baburajan; Thillaigovindan, Ranjani; Goyal, Nitin Kumar; Talukdar, Pratim; Seal, Mukut

2015-05-01

Newer dentin bonding agents were developed to improve the quality of composite restoration and to reduce time consumption in its application. The aim of the present study was to evaluate tensile bond strength of 6(th), 7(th) and 8(th) generation bonding agents by in vitro method. Selected 60 permanent teeth were assigned into 20 in each group (Group I: 6(th) generation bonding agent-Adper SE plus 3M ESPE, Group II: 7(th) generation bonding agent-G-Bond GC Corp Japan and Group III: 8(th) generation dentin adhesives-FuturaBond, DC, Voco, Germany). With high-speed diamond disc, coronal dentin was exposed, and selected dentin bonding agents were applied, followed by composite restoration. All samples were saved in saline for 24 h and tensile bond strength testing was done using a universal testing machine. The obtained data were tabulated and statistically analyzed using ANOVA test. The tensile bond strength readings for 6(th) generation bonding agent was 32.2465, for 7(th) generation was 31.6734, and for 8(th)-generation dentine bonding agent was 34.74431. The highest tensile bond strength was seen in 8(th) generation bonding agent compared to 6(th) and 7(th) generation bonding agents. From the present study it can be conclude that 8(th) generation dentine adhesive (Futura DC, Voco, Germany) resulted in highest tensile bond strength compared to 6(th) (Adper SE plus, 3M ESPE) and 7(th) generation (G-Bond) dentin bonding agents.

Comparison of sodium naphthenate and air-ionization corona discharge as surface treatments for the ethylene-tetrafluoroethylene polymer (ETFE) to improve adhesion between ETFE and acrylonitrile-butadiene-styrene polymer (ABS) in the presence of a cyanoacrylate adhesive (CAA)

NASA Astrophysics Data System (ADS)

Lucía Johanning-Solís, Ana; Stradi-Granados, Benito A.

2014-09-01

This study compares two ethylene-tetrafluoroethylene (ETFE) surface activation treatments, namely chemical attack with a solution of sodium naphthenate and plasma erosion via air-ionization corona discharge in order to improve the adhesive properties of the ETFE. An experimental design was prepared for both treatments in order to assess the effect of the treatment characteristics on the tensile load needed to break the bond between the ETFE and the acrylonitrile-butadiene-styrene polymer (ABS) formed with a cyanoacrylate adhesive (CAA) applied between them. The reason for the selection of this problem is that both polymers are frequently used in the biomedical industry for their properties, and they need to be joined firmly in biomedical devices, and the cyanoacrylate adhesive is the adhesive traditionally used for fluoropolymers, in this case the ETFE, and the same CAA has also shown good adhesion with ABS. However, the strength of the bond for the triplet ETFE-CAA-ABS has not been reported and the improvement of the strength of the bond with surface treatments is not found in scholarly journals for modern medical devices such as stents and snares. Both treatments were compared based on the aforementioned design of experiments. The case where ETFE receives no surface treatment serves as the reference. The results indicated that the three factors evaluated (initial drying of the material, temperature of the chemical bath, and immersion time), and their interactions have no significant effect over the tensile load at failure (tensile strength) of the adhesive bond being evaluated. For the air-ionization corona discharge treatment, two factors were evaluated: discharge exposition time and air pressure. The results obtained from this experimental design indicate that there is no significant difference between the levels of the factors evaluated. These results were unexpected as the ranges used were representative of the maximum ranges permissible in manufacturing operations. As for the comparison of the treatments, it was determined that the treatments have statistically significant differences. It was also determined that there is a significant statistical difference between the processes where a surface treatment is performed and the process where no surface treatment is applied to the ETFE. The chemical treatment results in a higher tensile load at failure (tensile strength) of 276.6 N on average, the air ionization treatment has an average of 248.4 N, and the process with no treatment has the lower ultimate tensile strength average of 53 N. This comparison has demonstrated that the best treatment is the chemical treatment with sodium naphthenate under the conditions tested.

Effect of UV irradiation on the shear bond strength of titanium with segmented polyurethane through gamma-mercapto propyl trimethoxysilane.

PubMed

Sakamoto, Harumi; Hirohashi, Yohei; Doi, Hisashi; Tsutsumi, Yusuke; Suzuki, Yoshiaki; Noda, Kazuhiko; Hanawa, Takao

2008-01-01

The objective of this study was to investigate the effect of UV irradiation on shear bond strength between a titanium (Ti) and a segmented polyurethane (SPU) composite through gamma-mercapto propyl trimethoxysilane (gamma-MPS). To this end, the shear bond strength of Ti/SPU interface of Ti-SPU composite under varying conditions of ultraviolet ray (UV) irradiation was evaluated by a shear bond test. The glass transition temperatures of SPU with and without UV irradiation were also determined using differential scanning calorimetry. It was found that the shear bond strength of Ti/SPU interface increased with UV irradiation. However, excessive UV irradiation decreased the shear bond strength of Ti/SPU interface. Glass transition temperature was found to increase during 40-60 seconds of UV irradiation. In terms of durability after immersion in water at 37 degrees C for 30 days, shear bond strength was found to improve with UV irradiation. In conclusion, UV irradiation to a Ti-SPU composite was clearly one of the means to improve the shear bond strength of Ti/SPU interface.

Shear Bond Strength between Fiber-Reinforced Composite and Veneering Resin Composites with Various Adhesive Resin Systems.

PubMed

AlJehani, Yousef A; Baskaradoss, Jagan K; Geevarghese, Amrita; AlShehry, Marey A; Vallittu, Pekka K

2016-07-01

The aim of this research was to evaluate the shear bond strength of different laboratory resin composites bonded to a fiber-reinforced composite substrate with some intermediate adhesive resins. Mounted test specimens of a bidirectional continuous fiber-reinforced substrate (StickNet) were randomly assigned to three equal groups. Three types of commercially available veneering resin composites - BelleGlass®, Sinfony®, and GC Gradia® were bonded to these specimens using four different adhesive resins. Half the specimens per group were stored for 24 hours; the remaining were stored for 30 days. There were 10 specimens in the test group (n). The shear bond strengths were calculated and expressed in MPa. Data were analyzed statistically, and variations in bond strength within each group were additionally evaluated by calculating the Weibull modulus. Shear bond values of those composites are influenced by the different bonding resins and different indirect composites. There was a significant difference in the shear bond strengths using different types of adhesive resins (p = 0.02) and using different veneering composites (p < 0.01). Belle-Glass® had the highest mean shear bond strength when bonded to StickNet substrate using both Prime & Bond NT and OptiBond Solo Plus. Sinfony® composite resin exhibited the lowest shear bond strength values when used with the same adhesive resins. The adhesive mode of failure was higher than cohesive with all laboratory composite resins bonded to the StickNet substructure at both storage times. Water storage had a tendency to lower the bond strengths of all laboratory composites, although the statistical differences were not significant. Within the limitations of this study, it was found that bonding of the veneering composite to bidirectional continuous fiber-reinforced substrate is influenced by the brand of the adhesive resin and veneering composite. © 2015 by the American College of Prosthodontists.

[The influence of different opaque thickness on the bond strength of porcelain-fused-to metal restoration].

PubMed

Xu, Kan; He, Fan; Geng, Yi

2009-12-01

To study the influence of different opaque thickness on the bond strength of porcelain-fused-to metal (PFM) restorations. The testing sheets were made as the samples of ISO9693. With different sintering temperature and different opaque thickness on the bond strength of PFM restorations, the primary pressure of porcelain crack was measured by using three-points-bending test. Statistical analysis was carried out using a SPSS 10.0 software package. A post hoc multiple comparison test (Student-Newman-Keuls) was performed to evaluate the differences between the individual groups. In low sintering temperature group, the thin layer of opaque significantly improved the bond strength compared with thick layer of opaque (P<0.05). In high sintering temperature group, the thickness of opaque has no significant influence on the PFM bonding strength. Using the opaque, the bonding strength was better than those without opaque. The thickness of opaque has a little influence on the PFM bonding strength.

Development of FRP composite structural biomaterials: ultimate strength of the fiber/matrix interfacial bond in in vivo simulated environments.

PubMed

Latour, R A; Black, J

1992-05-01

Fiber reinforced polymer (FRP) composites are being developed as alternatives to metals for structural orthopedic implant applications. FRP composite fracture behavior and environmental interactions are distinctly different from those which occur in metals. These differences must be accounted for in the design and evaluation of implant performance. Fiber/matrix interfacial bond strength in a FRP composite is known to strongly influence fracture behavior. The interfacial bond strength of four candidate fiber/matrix combinations (carbon fiber/polycarbonate, carbon fiber/polysulfone, polyaramid fiber/polycarbonate, polyaramid fiber/polysulfone) were investigated at 37 degrees C in dry and in vivo simulated (saline, exudate) environments. Ultimate bond strength was measured by a single fiber-microdroplet pull-out test. Dry bond strengths were significantly decreased following exposure to either saline or exudate with bond strength loss being approximately equal in both the saline and exudate. Bond strength loss is attributed to the diffusion of water and/or salt ions into the sample and their interaction with interfacial bonding. Because bond degradation is dependent upon diffusion, diffusional equilibrium must be obtained in composite test samples before the full effect of the test environment upon composite mechanical behavior can be determined.

Bond strength of the porcelain repair system to all-ceramic copings and porcelain.

PubMed

Lee, Sang J; Cheong, Chan Wook; Wright, Robert F; Chang, Brian M

2014-02-01

The purpose of this study was to investigate the shear bond strength of the porcelain repair system on alumina and zirconia core ceramics, comparing this strength with that of veneering porcelain. Veneering ceramic (n = 12), alumina core (n = 24), and zirconia core (n = 24) blocks measuring 10 × 5 × 5 mm(3) were fabricated. Veneering ceramic blocks were used as the control. Alumina and zirconia core blocks were divided into 2 groups (n = 12 each), and a slot (2 × 2 × 4 mm(3)) filled with veneering ceramics was prepared into one of the alumina and zirconia core groups (n = 12). Followed by surface treatments of micro-abrasion with 30 μm alumina particles, etching with 35% phosphoric acid and silane primer and bond, composite resin blocks (2 × 2 × 2 mm(3)) were built up and light polymerized onto the treated surfaces by 3 configurations: (a) composite blocks bonded onto veneering ceramic surface alone, (b) composite blocks bonded onto alumina core or zirconia core surfaces, (c) a 50% surface area of the composite blocks bonded to veneering ceramics and the other 50% surface area of the composite blocks to alumina core or zirconia core surfaces. The shear bond strength of the composite to each specimen was tested by a universal testing machine at a 0.5 mm/min crosshead speed. The shear bond strength was analyzed by unpaired t-tests for within the configuration groups and ANOVA for among the different configuration groups. When the mean shear bond strength was compared within groups of the same configuration, there were no statistically significant differences. Comparison of the shear bond strength among groups of different configurations revealed statistically significant differences. The mean shear bond strength of composite onto 100% veneering ceramic surface and composite onto 50% veneering 50% all-ceramic cores was statistically higher than that of composite onto 100% all-ceramic cores; however, the differences of the shear bond strength of composite bonded only onto the veneering ceramic surface were not statistically significant from those of 50% surface area of composite bonded onto all-ceramic cores. No statistically significant differences in the bond strength of a porcelain repair system to alumina and zirconia copings were observed. Increasing the surface of veneering ceramics to a porcelain repair system improved the repair material's bond strength. © 2013 by the American College of Prosthodontists.

The effect of five kinds of surface treatment agents on the bond strength to various ceramics with thermocycle aging.

PubMed

Noda, Yukari; Nakajima, Masatoshi; Takahashi, Masahiro; Mamanee, Teerapong; Hosaka, Keiichi; Takagaki, Tomohiro; Ikeda, Masaomi; Foxton, Richard M; Tagami, Junji

2017-11-29

This study evaluated the effects of ceramic surface treatment agents on shear bond strengths to ceramic materials with and without thermocycling. Ceramic plates were prepared from feldspathic ceramic; AAA, lithium disilicate ceramic material; IPS e.max Press, zirconia ceramic; Lava. Ceramic surfaces were pretreated with one of five surface treatment agents (Clearfil PhotoBond mixed with Porcelainbond activator (PB), Clearfil SE One mixed with Porcelainbond activator (SO), Ceramic Primer (CP), Universal Primer (UP), Scotchbond Universal (SU)), and then a resin cement (Clapearl DC) was filled. After 0, 5,000, and 10,000 thermocycles, micro-shear bond strengths between ceramic-cement interfaces were determined. SU exhibited significantly lower initial bond strength to AAA and e.max than PB, SO, CP, and UP. For Lava, PB, SO, CP and SU exhibited higher initial bond strengths than UP. Thermocycles reduced bond strengths to all the ceramic materials with any surface treatment.

High bonding temperatures greatly improve soy adhesive wet strength

Treesearch

Charles R. Frihart; Thomas Coolidge; Chera Mock; Eder Valle

2016-01-01

Soy wood adhesive bond strengths reported in different literature studies are difficult to compare because a variety of temperatures and other conditions have been used for the bonding and testing step. Some reports have indicated bond strengths are sensitive to bonding temperature, but the reason(s) for this has not been intensively investigated. Although these prior...

Shear bond strengths of composite to dentin using six dental adhesive systems.

PubMed

Triolo, P T; Swift, E J; Barkmeier, W W

1995-01-01

The development of adhesive agents for bonding composite to dentin has rapidly evolved in recent years. It is postulated that dentin bond strengths in the range of 17 MPa are sufficient to resist the polymerization shrinkage of composite resins. The purpose of this study was to evaluate the shear bond strengths of the following dentin adhesive systems: All-Bond 2 (Bisco), Imperva Bond (Shofu), Optibond (Kerr), Permagen (Ultradent), ProBond (Caulk/Dentsply), and Scotchbond Multi-Purpose (3M). Sixty human molars (10 per group) were mounted in phenolic rings, and the occlusal surfaces were flat ground in dentin to 600 grit. The prepared dentin bonding sites were treated according to the directions for each of the systems evaluated. A gelatin capsule technique was used to bond Bis-Fil composite cylinders to the teeth. The specimens were stored in water at 37 degrees C for 24 hours. Mean shear bond strengths were as follows: Scotchbond Multi-Purpose: 23.1 +/- 2.6 MPa, All-Bond 2: 21.4 +/- 7.8 MPa, Imperva Bond: 19.8 +/- 6.1 MPa, Optibond: 19.7 +/- 3.6 MPa, ProBond: 16.3 +/- 4.5 MPa, and Permagen: 16.2 +/- 3.0 MPa. There was not a significant difference (P<0.05) in the bond strengths of Scotchbond Multi-Purpose, All-Bond 2, Imperva Bond, and Optibond. The bond strengths of Scotchbond Multi-Purpose and All-Bond 2 were significantly greater (P<0.05) than ProBond and Permagen. Current-generation dentin adhesive systems have approached or exceeded the theoretical threshold value to resist contraction stresses during polymerization of resin materials.

Evaluation of the influence of time and concentration of sodium hypochlorite on the bond strength of glass fibre post.

PubMed

Knight, Beau; Love, Robert M; George, Roy

2017-10-24

This study evaluated the effect of time and concentrations of sodium hypochlorite on the bond strength of a glass fibre post cemented in a root canal with resin cement. A total of 45 single-rooted extracted human teeth were prepared with Protaper ® universal files, randomly allocated into nine groups and then subjected to 1% or 4% NaOCl for a period of 1 min or 2 min. Fibre posts were then bonded into the root canal, sectioned and the bond strength tested using a push-out test. A longer irrigation time resulted in a significant reduction (P < 0.05) in bond strength, while a final additional irrigation with distilled water significantly reduced bond strength. The concentration of NaOCl did not significantly affect bond strength. Within the limitations of this study, it was observed that regardless of the concentration of NaOCl used, shorter irrigation times favoured better fibre post bonding. © 2017 Australian Society of Endodontology Inc.

Shear bond strength between autopolymerizing acrylic resin and Co-Cr alloy using different primers.

PubMed

Sanohkan, Sasiwimol; Urapepon, Somchai; Harnirattisai, Choltacha; Sirisinha, Chakrit; Sunintaboon, Panya

2012-01-01

This study aimed to examine the shear bond strength between cobalt chromium alloy and autopolymerizing acrylic resin using experimental primers containing 5, 10, and 15 wt% of 4-methacryloxyethyl trimellitic anhydride or 1, 2, and 3 wt% of 3-methacryloxypropyl-trimethoxysilane comparison to 5 commercial primers (ML primers, Alloy primer, Metal/Zirconia primer, Monobond S, and Monobond plus). Sixty alloy specimens were sandblasted and treated with each primer before bonded with an acrylic resin. The control group was not primed. The shear bond strengths were tested and statistically compared. Specimens treated with commercial primers significantly increased the shear bond strength of acrylic resin to cobalt chromium alloy (p<0.05). The highest shear bond strength was found in the Alloy primer group. Among experimental group, using 10 wt% of 4-methacryloxyethyl trimellitic anhydride -or 2 wt% of 3-methacryloxypropyltrimethoxysilane enhanced highest shear bond strength. The experimental and commercial primers in this study all improved bonding of acrylic resin to cobalt chromium alloy.

Thin and thick layers of resin-based sealer cement bonded to root dentine compared: Adhesive behaviour.

PubMed

Pane, Epita S; Palamara, Joseph E A; Messer, Harold H

2015-12-01

This study aims to evaluate tensile and shear bond strengths of one epoxy (AH) and two methacrylate resin-based sealers (EZ and RS) in thin and thick layers bonded to root dentine. An alignment device was prepared for accurate positioning of 20 root dentine cylinders in a predefined gap of 0.1 or 1 mm. Sealer was placed in the interface. Bond strength tests were conducted. Mode of failures and representative surfaces were evaluated. Data were analysed using anova and post-hoc tests, with P < 0.05. The thick layer of sealer produced higher bond strength, except for the shear bond strength of EZ. Significant differences between thin and thick layers were found only in tensile bond strengths of AH and RS. Mixed type of failure was constantly found with all sealers. Bond strengths of thick layers of resin-based sealers to root dentine tended to be higher than with thin layers. © 2015 Australian Society of Endodontology.

Tensile Bond Strength of Self Adhesive Resin Cement After Various Surface Treatment of Enamel.

PubMed

Sekhri, Sahil; Mittal, Sanjeev; Garg, Sandeep

2016-01-01

In self adhesive resin cements adhesion is achieved to dental surface without surface pre-treatment, and requires only single step application. This makes the luting procedure less technique-sensitive and decreases postoperative sensitivity. The purpose of this study was to evaluate bond strength of self adhesive resin after surface treatment of enamel for bonding base metal alloy. On the labial surface of 64 central incisor rectangular base metal block of dimension 6 mm length, 5mm width and 1 mm height was cemented with RelyX U200 and Maxcem Elite self adhesive cements with and without surface treatment of enamel. Surface treatment of enamel was application of etchant, one step bonding agent and both. Tensile bond strength of specimen was measured with universal testing machine at a cross head speed of 1mm/min. Least tensile bond strength (MPa) was in control group i.e. 1.33 (0.32) & 1.59 (0.299), Highest bond strength observed when enamel treated with both etchant and bonding agent i.e. 2.72 (0.43) & 2.97 (0.19) for Relyx U200 and Elite cement. When alone etchant and bonding agent were applied alone bond strength is 2.19 (0.18) & 2.24 (0.47) for Relyx U200, and 2.38 (0.27) 2.49 (0.16) for Max-cem elite. Mean bond strength was higher in case of Max-cem Elite as compared to RelyX U200 resin cement, although differences were non-significant (p > 0.05). Surface treatment of enamel increases the bond strength of self adhesive resin cement.

In Vitro Evaluation of Shear Bond Strength of Nanocomposites to Dentin

PubMed Central

Vellanki, Vinay Kumar; Shetty, Vikram K; Kushwah, Sudhanshu; Goyal, Geeta; Chandra, S.M. Sharath

2015-01-01

Aims: To compare the shear bond strength of nanocomposites to dentin using three different types of adhesive systems; and to test few specimens under Scanning Electron Microscope (SEM) for analysing whether the bond failure is adhesive or cohesive. Materials and Methods: Sixty human premolar teeth were selected and were randomly grouped, with 20 specimens in each group: group 1 - fluoride releasing dentin bonding agent; group 2 - antibacterial containing dentin bonding agent; and group 3 - one step conventional self etch adhesive. Each group was treated with its respective bonding agents, composite resin build up was done, and shear bond strengths were tested using Instron Universal testing machine. Few of the specimens were tested under SEM. Results: The results were statistically analysed using One-way ANOVA and paired t-test. It was observed that group 3 has the highest shear bond strength followed by group 2, and then group 1. Adhesive failures and mixed failures were most frequent types of failures as seen under SEM. Conclusion: Addition of antimicrobial agent decreases the bond strength of dentin bonding agent and addition of fluoride further decreases the bond strength. From SEM results it can be concluded that the zone of failure could not be defined and also that the failure mode was independent of the dentin bonding agent used. PMID:25738077

Effect of contamination and etching on enamel bond strength of new light-cured glass ionomer cements.

PubMed

Itoh, T; Matsuo, N; Fukushima, T; Inoue, Y; Oniki, Y; Matsumoto, M; Caputo, A A

1999-10-01

The effect of water and saliva contamination on the bond strength of metal orthodontic brackets cemented to etched (10% polyacrylic acid) and unetched human premolar enamel was investigated. Two bonding agents were used: one commercially available product (LC) and one experimental (EX) light-cured glass ionomer. Shear bond strength was measured after aging for 5 minutes, 15 minutes, and 24 hours. The results were compared by ANOVA and Scheffe's tests at p = 0.05. For LC, the bond strength of brackets bonded to etched enamel, with and without contamination, was statistically higher than that of brackets bonded to unetched enamel for all aging times. An exception was the bond strength to unetched enamel with saliva contamination after 24 hours; for EX, this value was statistically higher than that measured on unetched enamel with water contamination. Contamination by saliva did not reduce bond strength to unetched enamel. For both etched and unetched enamel, there was no significant difference between LC and EX after 24 hours for all contamination conditions.

Deposition of crystalline hydroxyapatite nano-particle on zirconia ceramic: a potential solution for the poor bonding characteristic of zirconia ceramics to resin cement.

PubMed

Azari, Abbas; Nikzad, Sakineh; Yazdani, Arash; Atri, Faezeh; Fazel Anvari-Yazdi, Abbas

2017-07-01

The poor bonding strength of zirconia to different dental substrates is one of the challenging issues in restorative dentistry. Hydroxyapatite is an excellent biocompatible material with fine bonding properties. In this study, it was hypothesized that hydroxyapatite coating on zirconia would improve its bond strength. Forty-five zirconia blocks were prepared and randomly divided into three groups: hydroxyapatite coating, sandblasting, and no preparation (control). The blocks were bonded to cement and the micro-shear bond strength was measured following load application. The bond strength values were analyzed with the Kruskal-Wallis test in 3 groups and paired comparisons were made using the Mann-Whitney U test. The failure patterns of the specimens were studied by a stereomicroscope and a scanning electron microscope and then analyzed by the chi-square test (significance level = 0.05). Deposition of hydroxyapatite on the zirconia surface significantly improved its bond strength to the resin cement in comparison with the control specimens (p < 0.0001). Also, the bond strength was similar to the sandblasted group (p = 0.34). The sandblasted and control group only showed adhesive failure, but the hydroxyapatite coated group had mixed failures, indicating the better quality of bonding (p < 0.0001). As a final point, hydroxyapatite coating on the zirconia surface improved the bond strength quality and values.

Improving the interlaminar shear strength of carbon fiber-epoxy composites through carbon fiber bromination

NASA Technical Reports Server (NTRS)

Jaworske, Donald A.; Maciag, Carolyn

1987-01-01

The use of bromine to improve the interlaminar shear strength of PAN-based carbon fibers was investigated. Composite test specimens fabicated from brominated T-300 fibers and a MY720 matrix exhibited on average a 30% improvement in ILSS over their pristine counterparts. Mass, electrical resistivity, density, contact angle, and scanning Auger microscopy results suggested a mechanism in which the bromine was covalently bonded to the surface of the fiber, and this resulted in an increased van der Waal's adhesion between fiber and matrix.

Microtensile bond strength of three simplified adhesive systems to caries-affected dentin.

PubMed

Scholtanus, J D; Purwanta, Kenny; Dogan, Nilgun; Kleverlaan, Cees J; Feilzer, Albert J

2010-08-01

The purpose of the study was to determine the microtensile bond strength of three different simplified adhesive systems to caries-affected dentin. Fifteen extracted human molars with primary carious lesions were ground flat until dentin was exposed. Soft caries-infected dentin was excavated with the help of caries detector dye. On the remaining hard dentin, a standardized smear layer was created by polishing with 600-grit SiC paper. Teeth were divided into three groups and treated with one of the three tested adhesives: Adper Scotchbond 1 XT (3M ESPE), a 2-step etch-andrinse adhesive, Clearfil S3 Bond (Kuraray), a 1-step self-etching or all-in-one adhesive, and Clearfil SE Bond (Kuraray), a 2-step self-etching adhesive. Five-mm-thick composite buildups (Z-250, 3M ESPE) were built and light cured. After water storage for 24 h at 37ºC, the bonded specimens were sectioned into bars (1.0 x 1.0 mm; n = 20 to 30). Microtensile bond strength of normal dentin specimens and caries-affected dentin specimens was measured in a universal testing machine (crosshead speed = 1 mm/min). Data were analyzed using two-way ANOVA and Tukey's post-hoc test (p < 0.05). No significant differences in bond strength values to normal dentin between the three adhesives were found. Adper Scotchbond 1 XT and Clearfil S3 Bond showed significantly lower bond strength values to caries-affected dentin. For Clearfil SE Bond, bond strength values to normal and caries-affected dentin were not significantly different. All the tested simplified adhesives showed similar bond strength values to normal dentin. For the tested 2-step etch-and-rinse adhesive and the all-in-one adhesive, the bond strength values to caries-affected dentin were lower than to normal dentin.

An Ex-vivo Shear and tensile bond strengths of orthodontic molar tubes bonded using different techniques.

PubMed

Abu-Alhaija, Elham; Jaradat, Mohammad; Alwahadni, Ahed

2017-03-01

Molar bonding procedures need continuous improvement to be widely accepted clinically and eventually replace molar bands. The purpose of this study was to determine the effects of enamel micro-abrasion and silane coating of the base of molar tubes on shear and tensile bond strengths of orthodontic molar tubes. A total of 200 third molars were randomly allocated into five groups of 40 teeth as follows: group 1: molar tubes bonded to etched teeth (37% phosphoric acid gel; control group); group 2: molar tubes bonded to etched teeth (37% phosphoric acid) with the addition of silane to the base of molar tubes; group 3: molar tubes bonded to teeth pre-treated with 18% hydrochloric acid and pumice (micro-abrasion); group 4: molar tubes bonded to teeth pre-treated with microabrasion with the addition of silane to the base of molar tubes; group 5: molar tubes bonded to teeth pre-treated with microabrasion before conventional acid etching combined with the addition of silane to the base of molar tubes. The bond strength testing was performed using a computer control electromechanical universal testing machine. The highest mean shear and tensile bond strengths were recorded in group 5 (13.81±2.54MPa and 13.97±2.29 MPa, respectively). Micro-abrasion alone (group 3) and the combination of enamel micro-abrasion and the addition of silane (group 4) produced bond strength values comparable to the control. Enamel surface pre-treatment (micro abrasion) before conventional acid etching combined with the addition of silane to the base of the molar tube produced the highest bond strengths among all tested groups. Key words: Molar, shear strength, tensile strength, orthodontic appliances.

An Ex-vivo Shear and tensile bond strengths of orthodontic molar tubes bonded using different techniques

PubMed Central

Alwahadni, Ahed

2017-01-01

Background Molar bonding procedures need continuous improvement to be widely accepted clinically and eventually replace molar bands. Material and Methods The purpose of this study was to determine the effects of enamel micro-abrasion and silane coating of the base of molar tubes on shear and tensile bond strengths of orthodontic molar tubes. A total of 200 third molars were randomly allocated into five groups of 40 teeth as follows: group 1: molar tubes bonded to etched teeth (37% phosphoric acid gel; control group); group 2: molar tubes bonded to etched teeth (37% phosphoric acid) with the addition of silane to the base of molar tubes; group 3: molar tubes bonded to teeth pre-treated with 18% hydrochloric acid and pumice (micro-abrasion); group 4: molar tubes bonded to teeth pre-treated with microabrasion with the addition of silane to the base of molar tubes; group 5: molar tubes bonded to teeth pre-treated with microabrasion before conventional acid etching combined with the addition of silane to the base of molar tubes. The bond strength testing was performed using a computer control electromechanical universal testing machine. Results The highest mean shear and tensile bond strengths were recorded in group 5 (13.81±2.54MPa and 13.97±2.29 MPa, respectively). Micro-abrasion alone (group 3) and the combination of enamel micro-abrasion and the addition of silane (group 4) produced bond strength values comparable to the control. Conclusions Enamel surface pre-treatment (micro abrasion) before conventional acid etching combined with the addition of silane to the base of the molar tube produced the highest bond strengths among all tested groups. Key words:Molar, shear strength, tensile strength, orthodontic appliances. PMID:28298990

Solvent-free thermoplastic-poly(dimethylsiloxane) bonding mediated by UV irradiation followed by gas-phase chemical deposition of an adhesion linker

NASA Astrophysics Data System (ADS)

Ahn, S. Y.; Lee, N. Y.

2015-07-01

Here, we introduce a solvent-free strategy for bonding various thermoplastic substrates with poly(dimethylsiloxane) (PDMS) using ultraviolet (UV) irradiation followed by the gas-phase chemical deposition of aminosilane on the UV-irradiated thermoplastic substrates. The thermoplastic substrates were first irradiated with UV for surface hydrophilic treatment and were then grafted with vacuum-evaporated aminosilane, where the alkoxysilane side reacted with the oxidized surface of the thermoplastic substrate. Next, the amine-terminated thermoplastic substrates were treated with corona discharge to oxidize the surface and were bonded with PDMS, which was also oxidized via corona discharge. The two substrates were then hermetically sealed and pressed under atmospheric pressure for 30 min at 60 °C. This process enabled the formation of a robust siloxane bond (Si-O-Si) between the thermoplastic substrate and PDMS under relatively mild conditions using an inexpensive and commercially available UV lamp and Tesla coil. Various thermoplastic substrates were examined for bonding with PDMS, including poly(methylmethacrylate) (PMMA), polycarbonate (PC), poly(ethyleneterephthalate) (PET) and polystyrene (PS). Surface characterizations were performed by measuring the contact angle and performing x-ray photoelectron spectroscopy analysis, and the bond strength was analyzed by conducting various mechanical force measurements such as pull, delamination, leak and burst tests. The average bond strengths for the PMMA-PDMS, PC-PDMS, PET-PDMS and PS-PDMS assemblies were measured at 823.6, 379.3, 291.2 and 229.0 kPa, respectively, confirming the highly reliable performance of the introduced bonding strategy.

Proceedings of the Second Annual Symposium for Nondestructive Evaluation of Bond Strength

NASA Technical Reports Server (NTRS)

Roberts, Mark J. (Compiler)

1999-01-01

Ultrasonics, microwaves, optically stimulated electron emission (OSEE), and computational chemistry approaches have shown relevance to bond strength determination. Nonlinear ultrasonic nondestructive evaluation methods, however, have shown the most effectiveness over other methods on adhesive bond analysis. Correlation to changes in higher order material properties due to microstructural changes using nonlinear ultrasonics has been shown related to bond strength. Nonlinear ultrasonic energy is an order of magnitude more sensitive than linear ultrasound to these material parameter changes and to acoustic velocity changes caused by the acoustoelastic effect when a bond is prestressed. Signal correlations between non-linear ultrasonic measurements and initialization of bond failures have been measured. This paper reviews bond strength research efforts presented by university and industry experts at the Second Annual Symposium for Nondestructive Evaluation of Bond Strength organized by the NDE Sciences Branch at NASA Langley in November 1998.

Adhesive bonding to polymer infiltrated ceramic.

PubMed

Schwenter, Judith; Schmidli, Fredy; Weiger, Roland; Fischer, Jens

2016-01-01

Aim of this study was to investigate the mechanism of adhesive bonding to the polymer-infiltrated ceramic VITA Enamic [VE]. Shear bond strength was measured with three resin composite cements: RelyX Unicem 2 Automix, Clearfil SA and Variolink II on polished surfaces of VE and its components silicate ceramic [SC] and polymer [PM] (n=12). Further, the effect of etching VE with 5% HF for 15-240 s and the application of silane coupling agents was analyzed in a screening test (n=6). Shear bond strength measurements were performed after 24 h of water storage at 37°C. Significant bonding to polished substrates could only be achieved on VE and SC when silane coupling agents were used. Etching of VE with 5% HF increased shear bond strength. Following silanization of etched VE, a further increase in shear bond strength could be established. Etching for more than 30 s did not improve shear bond strength.

[Effects of surface treatment and adhesive application on shear bond strength between zirconia and enamel].

PubMed

Li, Yinghui; Wu, Buling; Sun, Fengyang

2013-03-01

To evaluate the effects of sandblasting and different orthodontic adhesives on shear bond strength between zirconia and enamel. Zirconia ceramic samples were designed and manufactured for 40 extracted human maxillary first premolars with CAD/CAM system. The samples were randomized into 4 groups for surface treatment with sandblasting and non-treated with adhesives of 3M Transbond XT or Jingjin dental enamel bonding resin. After 24 h of bonded fixation, the shear bond strengths were measured by universal mechanical testing machine and analyzed with factorial variance analysis. The shear bond strength was significantly higher in sandblasting group than in untreated group (P<0.05) and comparable between the two groups with the adhesives of Transbond XT and dental enamel bonding resin (P>0.05). The shear bond strength between zirconia and enamel is sufficient after sandblasting regardless of the application of either adhesive.

Development and Demonstration of a Multiplexed Magnetic Tweezers Assay

NASA Astrophysics Data System (ADS)

Johnson, Keith Charles

This dissertation is concerned with the methods and applications of single molecule force spectroscopy. In the introduction, the traditional single molecule force spectroscopy instruments are introduced and the advantages and drawbacks of each are discussed. The first chapter is a review of methods to ensure that biomolecular bond lifetime parameter estimations are not contaminated by multiple bond data. This review culminates in an examination of the literature on the strength of the bond between biotin and streptavidin and finds that by filtering the numerous publications for those that clearly demonstrate specific single bond behavior, there is a consensus of the bond strength and kinetic parameters. The second chapter of the dissertation discusses the capabilities of a magnetic tweezer assay, which combines massive multiplexing, precision bead tracking, and bi-directional force control into a flexible and stabile platform for examining single molecule behavior. Using a novel method for increasing the precision of force estimations on heterogeneous paramagnetic beads, I demonstrate the instrument by examining the force dependence of uncoiling and recoiling velocity of type 1 fimbriae from Eschericia coli (E. coli) bacteria, and see similar results to previous studies. Chapter 3 is a study of the lifetime of the activated FimH-mannose bond under various force conditions using the previously described magnetic tweezer. The bond is found to be extremely long-lived at forces less than 30 pN, with an average lifetime > 1000 times longer than the biotin-streptavidin bond, making it one of the strongest non-covalent interactions known in nature. Furthermore, the average lifetime of the bond is similar between 9 and 30 pN of force, suggesting a force range at which the lifetime is force-independent, demonstrating ideal bond behavior for the first time in a natural system. It is hypothesized that the long lifetime and ideal behavior is due to a gateway that locks mannose into the binding pocket and opens at a rate independent of force. This study elucidates a mechanism for very strong biological binding, and provides insight into approaches for developing novel antiadhesive therapies. This dissertation is concluded with a review of the body of work in chapters 1-3 and a discussion of the future directions for this research.

Bond strengths of Scotchbond Multi-Purpose to moist dentin and enamel.

PubMed

Swift, E J; Triolo, P T

1992-12-01

This in vitro study tested the shear bond strengths of the Scotchbond Multi-Purpose adhesive system to moist and dry enamel and dentin. After the tooth was etched, the surface was either dried with compressed air or blotted with tissue paper, leaving the surface visibly moist. Primer and adhesive were applied according to the manufacturer's directions. Resin composite posts were applied, and the specimens were thermocycled. Shear bond strengths were determined using an Instron universal testing machine. For both enamel and dentin, mean shear bond strengths were higher when the surface was left visibly moist after etching. Bond strengths to moist and dry dentin were 21.8 and 17.8 MPa, respectively. Enamel bond strengths were slightly lower, with values of 17.0 and 14.2 MPa to moist and dry enamel, respectively.

Comparative Evaluation of Impact Strength of Fragment Bonded Teeth and Intact Teeth: An In Vitro Study

PubMed Central

Venugopal, L; Lakshmi, M Narasimha; Babu, Devatha Ashok; Kiran, V Ravi

2014-01-01

Background: To test and compare the impact strength of fragment bonded teeth with that of intact teeth by using impact testing machine (pendulum type) as a mode of load. Materials and Methods: Forty extracted, maxillary, central incisors selected for this study (20 control group and 20 experimental group). In experimental group, teeth crowns were fractured with a microtome at 2.5 mm from mesioincisal angle cervically, fractured portion is attached to original crown portion with 3 M single bond dentin bonding agent and 3 M Z ‘100’, composite resin. Impact strength of fragment bonded teeth and intact teeth tested with impact testing machine and compared. Results: Mean impact strength of fragment bonded teeth (30.76 KJ/M2 ) is not statistically significant deferent from mean impact strength of intact teeth (31.11 KJ/M2 ). Conclusion: Mean impact strength of fragment bonded teeth is not statistically different with that of intact teeth. Hence, after fracture of teeth if it is restored with fragment reattachment by using 3 M single bond dentin bonding agent and 3 M Z ‘100’ composite resin is having impact strength like that of intact teeth. How to cite the article: Venugopal L, Lakshmi MN, Babu DA, Kiran VR. Comparative evaluation of impact strength of fragment bonded teeth and intact teeth: An in vitro study. J Int Oral Health 2014;6(3):73-6. PMID:25083037

Comparison of the push-out shear bond strength of four types of glass ionomers when used to bond amalgam: An in vitro study

PubMed Central

Mathew, Vinod Babu; Ramachandran, S; Indira, R; Shankar, P

2011-01-01

Background: Dental amalgam is the primary direct posterior restorative material used worldwide, but it have certain shortcomings due to the lack of adhesiveness to the cavity. The introduction of the concept of bonded amalgam helped improve the use of amalgam as a restorative material. Aim: Evaluation of the comparative push-out shear bond strength of four types of conventional glass ionomers used to bond amalgam to tooth in simulated class I situations. Materials and Methods: Four chemical cure glass ionomers are used: GC Fuji I, GC Fuji II, GC Fuji III and GC Fuji VII, and are compared with unbonded amalgam. The push-out bond strength was tested using the Instron Universal Testing Machine at a crosshead speed of 0.5 mm/min. Statistical Analysis: One-way ANOVA and post hoc Bonferroni tests were used to analyze the data. Results: The results showed that the use of glass ionomer to bond amalgam resulted in an increase in the bond strength of amalgam. The Type VII glass ionomer showed the highest bond strength in comparison with the other glass ionomers. Conclusions: Conventional glass ionomer bonds to amalgam and shows a beneficial increase in the bond strength of the restoration in comparison with unbonded amalgam. PMID:22144798

Influence of different repair procedures on bond strength of adhesive filling materials to etched enamel in vitro.

PubMed

Hannig, Christian; Hahn, Petra; Thiele, Patrick-Philipp; Attin, Thomas

2003-01-01

Contamination of etched enamel with repair bond agents during repair of dental restorations may interfere with the bonding of composite to enamel. This study examined the bond strength of adhesive filling materials to etched bovine enamel after pre-treatment with the repair systems Monobond S, Silibond and Co-Jet. The materials Tetric Ceram, Dyract and Definite and their corresponding bonding agents (Syntac Single Comp, Prime & Bond NT, Etch and Prime) were tested in combination with the repair systems. One hundred and thirty-five enamel specimens were etched (37% phosphoric acid, 60 seconds) and equally distributed among three groups (A-C). In Group A, the repair materials were applied on etched enamel followed by applying the composite materials without using their respective bonding material. In Group B, the composite materials were placed on etched enamel after applying the repair materials and bonding agents. In control Group C, the composite materials and bonding agents were applied on etched enamel without using the repair systems. In each sub-group, every composite material was applied on 15 specimens. Samples were stored in artificial saliva for 14 days and thermocycled 1,000 times (5 degrees C/55 degrees C). The shear bond strength of the samples were then determined in a universal testing machine (ISO 10477). Applying Monobond or Silibond followed by the use of its respective bonding agents resulted in a bond strength that was not statistically different from the controls for all filling materials (Group C). The three composites that used Monobond and Silibond without applying the corresponding bonding agent resulted in bond strengths that were significantly lower than the controls. Utilizing the Co-Jet-System drastically reduced the bond strength of composites on etched enamel. Contamination of etched enamel with the repairing bonding agents Monobond and Silibond does not interfere with bond strength if the application of Monobond and Silibond is followed by using its corresponding bonding system of the composites tested.

Tensile Bond Strength of Self Adhesive Resin Cement After Various Surface Treatment of Enamel

PubMed Central

Sekhri, Sahil; Garg, Sandeep

2016-01-01

Introduction In self adhesive resin cements adhesion is achieved to dental surface without surface pre-treatment, and requires only single step application. This makes the luting procedure less technique-sensitive and decreases postoperative sensitivity. Aim The purpose of this study was to evaluate bond strength of self adhesive resin after surface treatment of enamel for bonding base metal alloy. Materials and Methods On the labial surface of 64 central incisor rectangular base metal block of dimension 6 mm length, 5mm width and 1 mm height was cemented with RelyX U200 and Maxcem Elite self adhesive cements with and without surface treatment of enamel. Surface treatment of enamel was application of etchant, one step bonding agent and both. Tensile bond strength of specimen was measured with universal testing machine at a cross head speed of 1mm/min. Results Least tensile bond strength (MPa) was in control group i.e. 1.33 (0.32) & 1.59 (0.299), Highest bond strength observed when enamel treated with both etchant and bonding agent i.e. 2.72 (0.43) & 2.97 (0.19) for Relyx U200 and Elite cement. When alone etchant and bonding agent were applied alone bond strength is 2.19 (0.18) & 2.24 (0.47) for Relyx U200, and 2.38 (0.27) 2.49 (0.16) for Max-cem elite. Mean bond strength was higher in case of Max-cem Elite as compared to RelyX U200 resin cement, although differences were non–significant (p > 0.05). Conclusion Surface treatment of enamel increases the bond strength of self adhesive resin cement. PMID:26894165

Chemical, Calcium Phosphate Cements for Geothermal Wells - Corrosion Protection, Bond Strength and Matrix Self-Healing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sugama, Toshifumi

The data set shows performance of economical calcium phosphate cement (Fondu) blended with fly ash, class F (FAF) in carbon steel corrosion protection tests (corrosion rate, corrosion current and potential), bond- and matrix strength, as well as matrix strength recovery after imposed damage at 300C. The corrosion protection and lap-shear bond strength data are given for different Fondu/FAF ratios, the matrix strength data recoveries are reported for 60/40 weight % Fondu/FAF ratios. Effect of sodium phosphate on bond strength, corrosion protection and self-healing is demonstrated.

Shear bond strength of orthodontic brackets and disinclusion buttons: effect of water and saliva contamination.

PubMed

Sfondrini, Maria Francesca; Fraticelli, Danilo; Gandini, Paola; Scribante, Andrea

2013-01-01

The aim of this study was to assess the effect of water and saliva contamination on the shear bond strength and failure site of orthodontic brackets and lingual buttons. 120 bovine permanent mandibular incisors were randomly divided into 6 groups of 20 specimens each. Both orthodontic brackets and disinclusion buttons were tested under three different enamel surface conditions: (a) dry, (b) water contamination, and (c) saliva contamination. Brackets and buttons were bonded to the teeth and subsequently tested using a Instron universal testing machine. Shear bond strength values and adhesive failure rate were recorded. Statistical analysis was performed using ANOVA and Tukey tests (strength values) and Chi squared test (ARI Scores). Noncontaminated enamel surfaces showed the highest bond strengths for both brackets and buttons. Under water and saliva contamination orthodontic brackets groups showed significantly lower shear strengths than disinclusion buttons groups. Significant differences in debond locations were found among the groups under the various enamel surface conditions. Water and saliva contamination of enamel during the bonding procedure lowers bond strength values, more with orthodontic brackets than with disinclusion buttons.

[Bond strength evaluation of four adhesive systems to dentin in vitro].

PubMed

Xiao, Ximei; Xing, Lu; Xu, Haiping; Jiang, Zhe; Su, Qin

2012-08-01

To compare the adhesive strength and observe the bonding interface. According to statistic analysis and scanning electron microscope (SEM) observation, the resistance capacity of four adhesive systems is evaluated. Prime & Bond NT (PBNT), Tetric N-Bond (TNB), Clearfil SE Bond (CSEB), G Bond (GB) were bonded to the occlusal surfaces and mesial surfaces of third molars respectively. The mesial resins received shear force experiment and the fracture load were recorded. The tensile bond strength (TBS) of the remaining parts were tested. The interfacial configuration were observed under SEM. In the shear bond strength (SBS) experiment, PBNT and TNB showed the best result, but there was no significant difference between them (P>0.05). The SBS of PBNT was stronger than that of CSEB and GB (P<0.05). The SBS of TNB was stronger than that of GB (P<0.05). There was no significant difference between TNB and CSEB (P>0.05). In accordance with the shear force result, the TBS of PBNT and TNB was larger than CSEB and GB (P<0.05). Under SEM, resin tags of PBNT and TNB were longer and slender, the bonding layer was thick. Resin tags of CSEB were shorter, the ones of GB were the fewest and shortest. Compared to self-etching system, total-etching system could reach better bonding strength. There is some connection between the interfacial configuration of adhesives and bond strength of them.

Influence of etching time and bonding strategies on the microshear bond strength of self- and light-cured pit-and-fissure sealants.

PubMed

Souza-Junior, Eduardo José; Borges, Boniek Castillo Dutra; Montes, Marcos Antônio Japiassú Resende; Alonso, Roberta Caroline Bruschi; Ambrosano, Glaucia Maria Bovi; Sinhoreti, Mário Alexandre Coelho

2012-01-01

This study evaluated the impact of extended etching and bonding strategies on the microshear bond strength of three sealant materials. Two pit-and-fissure sealants [FluroShield, Dentsply (light-cured) and AlphaSeal, DFL (self-cured)] and one light-cured flowable composite resin (Permaflo, Ultradent) were evaluated according to different enamel etching times (15 s or 30 s) and bonding procedures (no adhesive application, application of primer/hydrophobic resin or hydrophobic resin only). Intact enamel blocks were obtained from bovine teeth and sealed via the tested protocols. After 24 h, the microshear bond strength test was performed in a universal testing machine at a crosshead speed of 0.5 mm/min. Failure modes were classified by stereomicroscopy. Data were submitted to a three-way ANOVA and to Tukey's test (α=0.05). There was no statistically significant difference (p>0.05) among the materials. Permaflo showed higher bond strength when etched for 30 s alone. Enamel overetching decreased the bond strength of the light-cured sealant. Primer/bond previous treatment improved bond performance for AlphaSeal. In conclusion, from the tested conditions, all sealant materials presented similar bond strength values in relation to bonding protocol and etching time. The flowable composite can be used as a pit-and-fissure sealant. The use of a three-step adhesive system was essential for the self-cured sealant application.

Short communication: pre- and co-curing effect of adhesives on shear bond strengths of composite resins to primary enamel and dentine: an in vitro study.

PubMed

Viswanathan, R; Shashibhushan, K K; Subba Reddy, V V

2011-12-01

To evaluate and compare shear bond strengths of composite resins to primary enamel and dentine when the adhesives are pre-cured (light cured before the application of the resin) or co-cured (adhesive and the resin light cured together). Buccal surfaces of 80 caries-free primary molars were wet ground to create bonding surfaces on enamel and dentine and specimens mounted on acrylic blocks. Two bonding agents (Prime and Bond NT® and Xeno III®) were applied to either enamel or dentine as per manufacturer's instructions. In 40 specimens, the bonding agent was light cured immediately after the application (pre-cured). The other 40 specimens were not light cured until the composite resin application (co-cured). Resin composite cylinders were made incrementally using acrylic moulds over the adhesives and light cured. Specimens were stored in deionised water for 24 hours at room temperature. Shear bond strength was measured using an Instron universal testing machine (in MPa) and was analysed with Student's unpaired t test. Light curing the adhesive separately produced significantly higher bond strengths to primary dentine than co-curing (p<0.001). At the same time light curing the adhesive separately did not produce significantly different bond strengths to primary enamel (p>0.05). Curing sequence had no significant effect on shear bond strength of adhesives on the primary enamel. Pre-curing adhesives before curing composite resins produced greater shear bond strength to primary dentine.

Radical Nature of C-Lignin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Berstis, Laura; Elder, Thomas; Crowley, Michael

The recently discovered lignin composed of caffeoyl alcohol monolignols or C-lignin is particularly intriguing given its homogeneous, linear polymeric structure and exclusive benzodioxane linkage between monomers. By virtue of this simplified chemistry, the potential emerges for improved valorization strategies with C-lignin relative to other natural heterogeneous lignins. To better understand caffeoyl alcohol polymers, we characterize the thermodynamics of the radical recombination dimerization reactions forming the benzodioxane linkage and the bond dissociation into radical monolignol products. These properties are also predicted for the cross-coupling of caffeoyl alcohol with the natural monolignols, coniferyl alcohol, sinapyl alcohol, and p-coumaryl alcohol, in anticipation of polymers potentially enabled by genetic modification. The average BDEs for the C-lignin benzodioxanemore » $$\\alpha$$- and β-bonds are 56.5 and 63.4 kcal/mol, respectively, with similar enthalpies for heterodimers. The BDE of the $$\\alpha$$-bond within the benzodioxane linkage is consistently greater than that of the β-bond in all dimers of each stereochemical arrangement, explained by the ability the $$\\alpha$$-carbon radical generated to delocalize onto the adjacent phenyl ring. Relative thermodynamics of the heterodimers demonstrates that the substituents on the phenyl ring directly neighboring the bond coupling the monolignols more strongly impact the dimer bond strengths and product stability, compared to the substituents present on the terminal phenyl ring. Enthalpy comparisons furthermore demonstrate that the erythro stereochemical configurations of the benzodioxane bond are slightly less thermodynamically stable than the threo configurations. The overall differences in strength of bonds and reaction enthalpies between stereoisomers are generally found to be insignificant, supporting that postcoupling rearomatization is under kinetic control. Projecting the lowest-energy stereoisomer internal coordinates to longer polymer C-lignin strands highlights how significantly the stereochemical outcomes in polymerization may impact the macromolecular structure and in turn material and chemical properties. Lastly, through these comparisons of geometry, bond strengths, and reaction enthalpies, we shed light on the distinctive properties of C-lignin's radical recombination and decomposition chemistry, and its potential as a natural lignin solution for biorefinery feedstocks and unique materials science applications.« less

Radical Nature of C-Lignin

DOE PAGES

Berstis, Laura; Elder, Thomas; Crowley, Michael; ...

2016-05-17

The recently discovered lignin composed of caffeoyl alcohol monolignols or C-lignin is particularly intriguing given its homogeneous, linear polymeric structure and exclusive benzodioxane linkage between monomers. By virtue of this simplified chemistry, the potential emerges for improved valorization strategies with C-lignin relative to other natural heterogeneous lignins. To better understand caffeoyl alcohol polymers, we characterize the thermodynamics of the radical recombination dimerization reactions forming the benzodioxane linkage and the bond dissociation into radical monolignol products. These properties are also predicted for the cross-coupling of caffeoyl alcohol with the natural monolignols, coniferyl alcohol, sinapyl alcohol, and p-coumaryl alcohol, in anticipation of polymers potentially enabled by genetic modification. The average BDEs for the C-lignin benzodioxanemore » $$\\alpha$$- and β-bonds are 56.5 and 63.4 kcal/mol, respectively, with similar enthalpies for heterodimers. The BDE of the $$\\alpha$$-bond within the benzodioxane linkage is consistently greater than that of the β-bond in all dimers of each stereochemical arrangement, explained by the ability the $$\\alpha$$-carbon radical generated to delocalize onto the adjacent phenyl ring. Relative thermodynamics of the heterodimers demonstrates that the substituents on the phenyl ring directly neighboring the bond coupling the monolignols more strongly impact the dimer bond strengths and product stability, compared to the substituents present on the terminal phenyl ring. Enthalpy comparisons furthermore demonstrate that the erythro stereochemical configurations of the benzodioxane bond are slightly less thermodynamically stable than the threo configurations. The overall differences in strength of bonds and reaction enthalpies between stereoisomers are generally found to be insignificant, supporting that postcoupling rearomatization is under kinetic control. Projecting the lowest-energy stereoisomer internal coordinates to longer polymer C-lignin strands highlights how significantly the stereochemical outcomes in polymerization may impact the macromolecular structure and in turn material and chemical properties. Lastly, through these comparisons of geometry, bond strengths, and reaction enthalpies, we shed light on the distinctive properties of C-lignin's radical recombination and decomposition chemistry, and its potential as a natural lignin solution for biorefinery feedstocks and unique materials science applications.« less

Does Acid Challenge Affect the Properties and Bond Stability of Restorative Materials on Primary Teeth?

PubMed

Tedesco, Tamara K; Calvo, Ana F B; Yoshioka, Laysa; Fukushima, Karen A; Cesar, Paulo F; Raggio, Daniela P

2018-05-31

To evaluate the effect of acidic challenge (AC) on the properties and bond stability of restorative materials to primary enamel and dentin. One hundred twenty primary molars were assigned to 12 groups according to substrate (enamel or dentin), restorative material (composite, high-viscosity glass ionomer cement [HV-GIC] or resin-modified glass-ionomer cement [RM-GIC]), and immersion after restoration (control [saline solution/7 days] or AC [cola-based drink/5 min/3x per day/7 days]). Twenty-four hours after the restorative procedure, specimens were submitted to one of the proposed challenges. Half of the specimens were immediately subjected to the microshear bond strength test, and the other half after 12 months. To determine flexural strength flexural strength and superficial roughness (SR), 30 specimens were built up. After 24 h, the first measurement of SR from 10 specimens was performed. Specimens were then immersed in one of proposed challenges and SR was measured again. Subsequently, flexural strength testing was performed. Bond strength, surface roughness, and flexural strength data were subjected to ANOVA and Tukey's test. Composite showed the highest bond strengths compared to the others materials on both substrates. The storage period negatively influenced the bond strength only for composite groups in dentin. AC after restoration negatively influenced bond strength when the materials were evaluated in eroded dentin. AC affected the second SR measurement, showing increased SR for all restorative materials. AC did not affect flexural strength. The acidic challenge jeopardizes the surface roughness and bond strength of restorations to eroded dentin.

Bond strength comparison of 2 self-etching primers over a 3-month storage period.

PubMed

Trites, Brian; Foley, Timothy F; Banting, David

2004-12-01

The purpose of this in vitro study was to evaluate the shear-peel bond strength of 2 self-etching primer systems, Transbond Plus (3M/ Unitek, Monrovia, Calif) and First Step (Reliance Orthodontic Products, Itasca, Ill), with their respective adhesives, and compare them with a control adhesive system (Transbond XT, 3M/ Unitek) over a 3-month period. Two hundred seventy extracted human premolars were obtained and randomly divided into 9 groups of 30 teeth. Metal orthodontic brackets were bonded to the enamel, and each adhesive group was stored for 24 horrs (T1), 30 days (T2), or 3 months (T3) in deionized water at 37 degrees C. All bonded specimens were thermocycled at 10 degrees C and 50 degrees C for 24 hours before debonding. Brackets were debonded by using a shear-peel load on a testing machine at a cross-head speed of 2 mm/min. Bond failure was also evaluated. The shear-peel bond strengths of the 3 bonding systems were clinically acceptable with the possible exception of First Step at 30-day storage. Repeated measures analysis of variance showed a statistically significant (P < .0001) difference in mean bond strengths between the 3 adhesive systems. The shear-peel bond strength of the adhesives over the 3 time intervals showed statistically significant (P = .005) changes. In each group, there were statistically significant differences in shear-peel bond strength between time intervals T1-T2 and T2-T3 for Transbond Plus and T2-T3 for First Step. The change in mean shear-peel bond strength of the 3 adhesives demonstrated a consistent pattern of behavior over the 3 storage intervals. The lowest mean shear-peel bond strength values were noted at the 30-day storage. Bond failure analysis (adhesive remnant index) demonstrated mainly cohesive bond failures.

Antibacterial Effect and Tensile Bond Strength of Self-etching Adhesive Resins with and without Methacryloyloxydodecylpyridinium Bromide: An in vitro Study.

PubMed

Krishnamurthy, Madhuram; Kumar, V Naveen; Leburu, Ashok; Dhanavel, Chakravarthy; Selvendran, Kasiswamy E; Praveen, Nehrudhas

2018-04-01

Aim: The aim of the present study was to compare the antibacterial activity of a self-etching primer containing antibacterial monomer methacryloyloxydodecylpyridinium bromide (MDPB) (Clearfil protect bond) with a conventional self-etching primer without MDPB (Clearfil SE bond) against Streptococcus mutans and the effect of incorporation of MDPB on the tensile bond strength of the experimental self-etching primer (Clearfil protect bond). Materials and methods: The antibacterial activity of the self-etching primers was assessed using agar disk diffusion method and the diameters of the zones of inhibition were measured and ranked. For tensile bond strength testing, 20 noncarious human molars were selected and randomly divided into two groups comprising 10 teeth in each group. Group I specimens were treated with Clearfil SE bond (without MDPB). Group II specimens were treated with Clearfil protect bond (with MDPB). Composite material was placed incrementally and cured for 40 seconds in all the specimens. Tensile bond strength was estimated using the Instron Universal testing machine at a crosshead speed of 1 mm/min. Results: The addition of MDPB into a self-etching primer exerts potential antibacterial effect against S. mutans. The tensile bond strength of MDPB containing self-etching primer was slightly lower than that of the conventional self-etching Clearfil protect bond primer, but the difference was not statistically significant. Conclusion: Thus, a self-etching primer containing MDPB will be a boon to adhesive dentistry as it has bactericidal property with adequate tensile bond strength. Clinical significance: The concept of prevention of extension in adhesive dentistry would result in micro/nanoleakage due to the presence of residual bacteria in the cavity. Self-etching primers with MDPB would improve the longevity of such restorations by providing adequate antibacterial activity without compromising the bond strength. Keywords: Antibacterial property, Methacryloyloxydodecy-lpyridinium bromide, Self-etching primers, Tensile bond strength.

Bond strength of different adhesives to normal and caries-affected dentins.

PubMed

Xuan, Wei; Hou, Ben-xiang; Lü, Ya-lin

2010-02-05

Currently, several systems of dentin substrate-reacting adhesives are available for use in the restorative treatment against caries. However, the bond effectiveness and property of different adhesive systems to caries-affected dentin are not fully understood. The objective of this study was to evaluate the bond strength of different adhesives to both normal dentin (ND) and caries-affected dentin (CAD) and to analyze the dentin/adhesive interfacial characteristics. Twenty eight extracted human molars with coronal medium carious lesions were randomly assigned to four groups according to adhesives used. ND and CAD were bonded with etch-and-rinse adhesive Adper Single Bond 2 (SB2) or self-etching adhesives Clearfil SE Bond (CSE), Clearfil S(3) Bond (CS3), iBond GI (IB). Rectangular sticks of resin-dentin bonded interfaces 0.9 mm(2) were obtained. The specimens were subjected to microtensile bond strength (microTBS) testing at a crosshead speed of 1 mm/min. Mean microTBS was statistically analyzed with analysis of variance (ANOVA) and Student-Newman-Keuls tests. Interfacial morphologies were analyzed by Scanning Electron Microscopy (SEM). Etch-and-rinse adhesive Adper(TM) Single Bond 2 yielded high bond strength when applied to both normal and caries-affected dentin. The two-step self-etching adhesive Clearfil SE Bond generated the highest bond strength to ND among all adhesives tested but a significantly reduced strength when applied to CAD. For the one-step self-etching adhesives, Clearfil S(3) Bond and iBond GI, the bond strength was relatively low regardless of the dentin type. SEM interfacial analysis revealed that hybrid layers were thicker with poorer resin tag formation and less resin-filled lateral branches in the CAD than in the ND for all the adhesives tested. The etch-and-rinse adhesive performed more effectively to caries-affected dentin than the self-etching adhesives.

Resin-dentin bonds to EDTA-treated vs. acid-etched dentin using ethanol wet-bonding. Part II: Effects of mechanical cycling load on microtensile bond strengths.

PubMed

Sauro, Salvatore; Toledano, Manuel; Aguilera, Fatima Sánchez; Mannocci, Francesco; Pashley, David H; Tay, Franklin R; Watson, Timothy F; Osorio, Raquel

2011-06-01

To compare microtensile bond strengths (MTBS) subsequent to load cycling of resin bonded acid-etched or EDTA-treated dentin using a modified ethanol wet-bonding technique. Flat dentin surfaces were obtained from extracted human molars and conditioned using 37% H(3)PO(4) (PA) (15s) or 0.1M EDTA (60s). Five experimental adhesives and one commercial bonding agent were applied to the dentin and light-cured. Solvated experimental resins (50% ethanol/50% comonomers) were used as primers and their respective neat resins were used as the adhesives. The resin-bonded teeth were stored in distilled water (24h) or submitted to 5000 loading cycles of 90N. The bonded teeth were then sectioned in beams for MTBS. Modes of failure were examined by scanning electron microscopy. The most hydrophobic resin 1 gave the lowest bond strength values to both acid and EDTA-treated dentin. The hydrophobic resin 2 applied to EDTA-treated dentin showed lower bond strengths after cycling load but this did not occur when it was bonded to PA-etched dentin. Resins 3 and 4, which contained hydrophilic monomers, gave higher bond strengths to both EDTA-treated or acid-etched dentin and showed no significant difference after load cycling. The most hydrophilic resin 5 showed no significant difference in bond strengths after cycling loading when bonded to EDTA or phosphoric acid treated dentin but exhibited low bond strengths. The presence of different functional monomers influences the MTBS of the adhesive systems when submitted to cyclic loads. Adhesives containing hydrophilic comonomers are not affected by cycling load challenge especially when applied on EDTA-treated dentin followed by ethanol wet bonding. Copyright © 2011 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Effects of three silane primers and five adhesive agents on the bond strength of composite material for a computer-aided design and manufacturing system.

PubMed

Shinohara, Ayano; Taira, Yohsuke; Sakihara, Michino; Sawase, Takashi

2018-01-01

Objective The objective of this study was to evaluate the effects of combinations of silane primers and adhesive agents on the bond strength of a composite block for a computer-aided design and manufacturing system. Material and Methods Three silane primers [Clearfil Ceramic Primer (CP), Super-Bond PZ Primer (PZ), and GC Ceramic Primer II (GP)] were used in conjunction with five adhesive agents [G-Premio Bond (P-Bond), Repair Adhe Adhesive (R-Adhesive), Super-Bond D-Liner Dual (SB-Dual), Super-Bond C&B (SB-Self), and SB-Dual without tributylborane derivative (SB-Light)]. The surface of a composite block (Gradia Block) was ground with silicon carbide paper. After treatment with a silane primer, a adhesive agent was applied to each testing specimen. The specimens were then bonded with a light-curing resin composite. After 24 h, the shear bond strength values were determined and compared using a post hoc test (α=0.05, n=8/group). We also prepared control specimens without primer (No primer) and/or without adhesive agent (No adhesive). Results PZ/SB-Dual and GP/SB-Dual presented the highest bond strength, followed by GP/P-Bond, CP/SB-Dual, CP/R-Adhesive, No primer/SB-Dual, GP/R-Adhesive, CP/P-Bond, No primer/R-Adhesive, PZ/R-Adhesive, CP/SB-Self, PZ/P-Bond, PZ/SB-Self, and GP/SB-Self in descending order of bond strength. No primer/P-Bond, No primer/SB-Self, and all specimens in the SB-Light and No adhesive groups presented the lowest bond strengths. Conclusion A dual-curing adhesive agent (SB-Dual) containing a tributylborane derivative in combination with a silane primer (GP or PZ) presents a greater bond strength between the composite block and the repairing resin composite than the comparators used in the study.

Effects of three silane primers and five adhesive agents on the bond strength of composite material for a computer-aided design and manufacturing system

PubMed Central

2018-01-01

Abstract Objective The objective of this study was to evaluate the effects of combinations of silane primers and adhesive agents on the bond strength of a composite block for a computer-aided design and manufacturing system. Material and Methods Three silane primers [Clearfil Ceramic Primer (CP), Super-Bond PZ Primer (PZ), and GC Ceramic Primer II (GP)] were used in conjunction with five adhesive agents [G-Premio Bond (P-Bond), Repair Adhe Adhesive (R-Adhesive), Super-Bond D-Liner Dual (SB-Dual), Super-Bond C&B (SB-Self), and SB-Dual without tributylborane derivative (SB-Light)]. The surface of a composite block (Gradia Block) was ground with silicon carbide paper. After treatment with a silane primer, a adhesive agent was applied to each testing specimen. The specimens were then bonded with a light-curing resin composite. After 24 h, the shear bond strength values were determined and compared using a post hoc test (α=0.05, n=8/group). We also prepared control specimens without primer (No primer) and/or without adhesive agent (No adhesive). Results PZ/SB-Dual and GP/SB-Dual presented the highest bond strength, followed by GP/P-Bond, CP/SB-Dual, CP/R-Adhesive, No primer/SB-Dual, GP/R-Adhesive, CP/P-Bond, No primer/R-Adhesive, PZ/R-Adhesive, CP/SB-Self, PZ/P-Bond, PZ/SB-Self, and GP/SB-Self in descending order of bond strength. No primer/P-Bond, No primer/SB-Self, and all specimens in the SB-Light and No adhesive groups presented the lowest bond strengths. Conclusion A dual-curing adhesive agent (SB-Dual) containing a tributylborane derivative in combination with a silane primer (GP or PZ) presents a greater bond strength between the composite block and the repairing resin composite than the comparators used in the study. PMID:29742254

Microshear bond strength of self-etching systems associated with a hydrophobic resin layer.

PubMed

De Vito Moraes, André Guaraci; Francci, Carlos; Carvalho, Ceci Nunes; Soares, Silvio Peixoto; Braga, Roberto Ruggiero

2011-08-01

To evaluate in vitro the microshear bond strength of adhesive systems applied to dentin according to manufacturers' instructions, associated or not with a hydrophobic layer of unfilled resin. Six self-etching adhesives (Clearfil SE Bond, Kuraray Medical; AdheSE, Ivoclar Vivadent; Xeno III, Dentsply; I Bond, Heraeus-Kulzer; Bond Force, Tokuyama; Futurabond DC, Voco) were tested. The labial dentin of sixty bovine incisors was exposed, and the teeth were divided into two groups according to the application or not of an extra hydrophobic resin layer (Scotchbond Multi Purpose Plus, bottle 3). Six composite cylinders (Filtek Z250, 3M ESPE) were built up on each treated surface. Specimens were stored in distilled water at 37ºC for 24 h and then subjected to the microshear bond strength test in a universal testing machine at a crosshead speed of 0.5 mm/min. Microshear bond strength values were analyzed by 2-way ANOVA and Tukey's post-hoc test. Failure mode was determined using a stereomicroscope under 20X magnification. The application of the hydrophobic resin layer did not affect bond strength, except for AdheSE. However, the bond strengths with the hydrophobic layer were similar among the six tested systems (Clearfil: 17.1 ± 7.9; AdheSE: 14.5 ± 7.1; Xeno lll: 12.8 ± 7.7; I Bond: 9.5 ± 5.8; Bond Force: 17.5 ± 4.1; Futurabond: 7.7 ± 2.3). When used as recommended by the manufacturers, Bond Force presented statistically higher bond strength than AdheSE and I Bond (p < 0.05) (Clearfil 10.4 ± 4.9; AdheSE 1.6 ± 1.6; Xeno lll: 9.0 ± 3.8; I Bond: 3.0 ± 1.5; Bond Force: 14 ± 3.9; Futurabond: 8.8 ± 3.8). Failure mode was predominantly adhesive. The bond strength of the self-etching systems tested was not significantly affected by the application of a hydrophobic layer, but a significant improvement was observed in AdheSE.

Effect of different intracoronal bleaching methods on shear bond strength of ceramic brackets bonded to bleached enamel: An in-vitro study.

PubMed

Chauhan, Vikas; Kumar, Piush; Sharma, Payal; Shetty, Divya

2017-01-01

To investigate the effect of different intracoronal bleaching methods on the shear bond strength and site of failure of ceramic brackets. Sixty freshly extracted human maxillary incisors were randomly divided into four groups ( n = 15). Endodontic access cavity was prepared and root canals were filled, root fillings were removed 2mm apical to the cementoenamel junction, and a 2-mmthick layer of glass ionomer cement base was applied. Group 1 served as the control. Intracoronal bleaching was performed with 35% carbamide peroxide in group 2, sodium perborate in group 3, and 37.5% hydrogen peroxide in group 4. The teeth were immersed in artificial saliva for 4 weeks before bracket bonding. Ceramic brackets were bonded with composite resin and cured with LED light. After bonding, the shear bond strength of the brackets was tested with a universal testing machine. The site of bond failure was determined by modified ARI (Adhesive Remnant Index). The highest value of shear bond strength was measured in control group (18.67 ± 1.59 MPa), which was statistically significant from groups 2,3, and 4. There was no significant difference between groups 2 and 4. The lowest shear bond strength was measured in group 3. ARI scores were not significant from each other. Intracoronal bleaching significantly affected the shear bond strength of ceramic brackets even after 4 weeks of bleaching. Bleaching with sodium perborate affects shear bond strength more adversely than does bleaching with other agents like hydrogen peroxide and carbamide peroxide.

Effect of indirect composite treatment microtensile bond strength of self-adhesive resin cements

PubMed Central

Escribano, Nuria; Baracco, Bruno; Romero, Martin; Ceballos, Laura

2016-01-01

Background No specific indications about the pre-treatment of indirect composite restorations is provided by the manufacturers of most self-adhesive resin cements. The potential effect of silane treatment to the bond strength of the complete tooth/indirect restoration complex is not available.The aim of this study was to determine the contribution of different surface treatments on microtensile bond strength of composite overlays to dentin using several self-adhesive resin cements and a total-etch one. Material and Methods Composite overlays were fabricated and bonding surfaces were airborne-particle abraded and randomly assigned to two different surface treatments: no treatment or silane application (RelyX Ceramic Primer) followed by an adhesive (Adper Scotchbond 1 XT). Composite overlays were luted to flat dentin surfaces using the following self-adhesive resin cements: RelyX Unicem, G-Cem, Speedcem, Maxcem Elite or Smartcem2, and the total-etch resin cement RelyX ARC. After 24 h, bonded specimens were cut into sticks 1 mm thick and stressed in tension until failure. Two-way ANOVA and SNK tests were applied at α=0.05. Results Bond strength values were significantly influenced by the resin cement used (p<0.001). However, composite surface treatment and the interaction between the resin cement applied and surface treatment did not significantly affect dentin bond strength (p>0.05). All self-adhesive resin cements showed lower bond strength values than the total-etch RelyX ARC. Among self-adhesive resin cements, RelyX Unicem and G-Cem attained statistically higher bond strength values. Smartcem2 and Maxcem Elite exhibited 80-90% of pre-test failures. Conclusions The silane and adhesive application after indirect resin composite sandblasting did not improve the bond strength of dentin-composite overlay complex. Selection of the resin cement seems to be a more relevant factor when bonding indirect composites to dentin than its surface treatment. Key words:Bond strength, self-adhesive cement, silane, dentin, indirect composite. PMID:26855700

Comparison of hydroxyapatite and dental enamel for testing shear bond strengths.

PubMed

Imthiaz, Nishat; Georgiou, George; Moles, David R; Jones, Steven P

2008-05-01

To investigate the feasibility of using artificial hydroxyapatite as a future biomimetic laboratory substitute for human enamel in orthodontic bond strength testing by comparing the shear bond strengths and nature of failure of brackets bonded to samples of hydroxyapatite and enamel. One hundred and fifty hydroxyapatite discs were prepared by compression at 20 tons and fired in a furnace at 1300 degrees C. One hundred and five enamel samples were prepared from the buccal and palatal/lingual surfaces of healthy premolars extracted for orthodontic purposes. Orthodontic brackets were bonded to each sample and these were subjected to shear bond strength testing using a custom-made jig mounted in an Instron Universal Testing Machine. The force value at bond failure was obtained, together with the nature of failure which was assessed using the Adhesive Remnant Index. The mean shear bond strength for the enamel samples was 16.62 MPa (95 per cent CI: 15.26, 17.98) and for the hydroxyapatite samples 20.83 MPa (95 per cent CI: 19.68, 21.98). The difference between the two samples was statistically significant (p < 0.001). When the nature of failure was assessed with the ARI Index, 83 per cent of the enamel samples scored 2 or 3, while 49 per cent of the hydroxyapatite samples scored 0 or 1. Hydroxyapatite was an effective biomimetic substrate for bond strength testing with a mean shear bond strength value (20.83 MPa) at the upper end of the normal range attributed to enamel (15-20 MPa). Although the difference between the shear bond strengths for hydroxyapatite and enamel was statistically significant, hydroxyapatite could be used as an alternative to enamel for comparative laboratory studies until a closer alternative is found. This would eliminate the need for extracted teeth to be collected. However, it should be used with caution for quantitative studies where true bond strengths are to be investigated.

Buccal patches of atenolol formulated using fenugreek (Trigonella foenum-graecum L.) seed mucilage.

PubMed

Adhikari, Surya Narayan Ratha; Panda, Satyabrata

2017-01-01

The use of mucoadhesive natural polymers in designing mucoadhesive patch systems has received much attention. The study involved the development and evaluation of buccal patches of atenolol using fenugreek (Trigonella foenum-graecum L.) seed mucilage with hydroxylpropyl methyl cellulose (HPMC K4M) and a backing membrane (ethyl cellulose 5% w/v). These atenolol-releasing buccal patches were prepared using a solvent casting technique. The buccal patches prepared were evaluated for average weight, thickness, drug content, folding endurance and moisture content. Ex vivo mucoadhesive strength, force of adhesion and bonding strength were determined using porcine buccal mucosa. The mucosal permeation of atenolol through the porcine buccal mucosa was carried out using a Franz diffusion cell in phosphate buffer saline, pH 6.8. These buccal patches were also characterized by SEM and FTIR spectroscopy. The average weight, thickness, drug content, folding endurance and moisture content of these atenolol-releasing buccal patches were found satisfactory for all the patches. Amongst all, the F-4 buccal patch showed maximum mucoadhesive strength (31.12 ±1.86 g), force of adhesion (30.53 × 10-2 N) and bond strength (1748.89 N/m2). Ex vivo atenolol permeation from the buccal patches showed drug permeation across the excised porcine buccal mucosa over 12 h. The F-4 buccal patch showed maximum permeation flux (29.12 μg/cm2/h). The developed atenolol-releasing buccal patches can be beneficial over the conventional drug delivery systems to decrease the dosing frequency and enhance patient compliance.

Relationship between surface area for adhesion and tensile bond strength--evaluation of a micro-tensile bond test.

PubMed

Sano, H; Shono, T; Sonoda, H; Takatsu, T; Ciucchi, B; Carvalho, R; Pashley, D H

1994-07-01

The purpose of this study was to test the null hypothesis that there is no relationship between the bonded surface area of dentin and the tensile strength of adhesive materials. The enamel was removed from the occlusal surface of extracted human third molars, and the entire flat surface was covered with resin composite bonded to the dentin to form a flat resin composite crown. Twenty-four hours later, the bonded specimens were sectioned parallel to the long axis of the tooth into 10-20 thin sections whose upper part was composed of resin composite with the lower half being dentin. These small sections were trimmed using a high speed diamond bur into an hourglass shape with the narrowest portion at the bonded interface. Surface area was varied by altering the specimen thickness and width. Tensile bond strength was measured using custom-made grips in a universal testing machine. Tensile bond strength was inversely related to bonded surface area. At surface areas below 0.4 mm2, the tensile bond strengths were about 55 MPa for Clearfil Liner Bond 2 (Kuraray Co., Ltd.), 38 MPa for Scotchbond MP (3M Dental Products), and 20 MPa for Vitremer (3M Dental Products). At these small surface areas all of the bond failures were adhesive in nature. This new method permits measurement of high bond strengths without cohesive failure of dentin. It also permits multiple measurements to be made within a single tooth.

The impact of artificially caries-affected dentin on bond strength of multi-mode adhesives

PubMed Central

Follak, Andressa Cargnelutti; Miotti, Leonardo Lamberti; Lenzi, Tathiane Larissa; Rocha, Rachel de Oliveira; Maxnuck Soares, Fabio Zovico

2018-01-01

Aim: The aim of this study is to evaluate the impact of dentin condition on bond strength of multi-mode adhesive systems (MMAS) to sound and artificially induced caries-affected dentin (CAD). Methods: Flat dentin surfaces of 112 bovine incisors were assigned to 16 subgroups (n = 7) according to the substrate condition (sound and CAD– pH-cycling for 14 days); adhesive systems (Scotchbond Universal, All-Bond Universal, Prime and Bond Elect, Adper Single Bond Plus and Clearfil SE Bond) and etching strategy (etch-and-rinse and self-etch). All systems were applied according to the manufacturer's instructions, and resin composite restorations were built. After 24 h of water storage, specimens were sectioned (0.8 mm2) and submitted to the microtensile test. Statistical Analysis: Data (MPa) were analyzed using three-way analysis of variance and Tukey's test (α = 0.05). Results: MMAS presented similar bond strength values, regardless etching strategy in each substrate condition. Bond strength values were lower when MMAS were applied to CAD in the etch-and-rinse strategy. Conclusion: The etching strategy did not influence the bond strength of MMAS to sound or CAD, considering each substrate separately. However, CAD impact negatively on bond strength of MMAS in etch-and rinse mode. PMID:29674813

Fiber pushout test: A three-dimensional finite element computational simulation

NASA Technical Reports Server (NTRS)

Mital, Subodh K.; Chamis, Christos C.

1990-01-01

A fiber pushthrough process was computationally simulated using three-dimensional finite element method. The interface material is replaced by an anisotropic material with greatly reduced shear modulus in order to simulate the fiber pushthrough process using a linear analysis. Such a procedure is easily implemented and is computationally very effective. It can be used to predict fiber pushthrough load for a composite system at any temperature. The average interface shear strength obtained from pushthrough load can easily be separated into its two components: one that comes from frictional stresses and the other that comes from chemical adhesion between fiber and the matrix and mechanical interlocking that develops due to shrinkage of the composite because of phase change during the processing. Step-by-step procedures are described to perform the computational simulation, to establish bounds on interfacial bond strength and to interpret interfacial bond quality.

Shear Bond Strength of DentStat(trademark) for Bracket Bonding to Gold, Ceramic, and Enamel

DTIC Science & Technology

2012-12-21

i Shear bond strength of DentStatTM for bracket bonding to gold, ceramic, and enamel . A THESIS Presented to the Faculty of Uniform...in the thesis manuscript entitled: ’Shear Bond Strength of DentStatTM for Bracket Bonding to Gold, Ceramic, and Enamel ’ is appropriately...Ceramic, and Enamel ’ 7. Intended publication/meeting: June 2013 8. "Required by" date: 1 July 2013 9. Date of submission for USU approval: 6 June

Shear strengths of a gallium alloy bonded to human enamel following nine different surface treatments.

PubMed

Claire, J; Williams, P T

2001-03-01

Gallium and indium-containing alloys have demonstrated an ability to wet and bond to many types of materials including enamel. The purpose of this study was to evaluate and compare the bond strengths of a gallium-and-indium-containing alloy and a dental amalgam to human enamel surfaces. A flat enamel bonding surface was created by slicing recently extracted human molars with a 180-grit diamond wheel. Cylinders of amalgam or a gallium-indium alloy were bonded to the as-cut surfaces or to as-cut surfaces that had been pumiced, air-abraded or acid-etched for various times. Before testing, samples were stored under different conditions (100% humidity, immersed in water, thermocycled). The shear-bond strength was determined using a crosshead speed of 0.1 mm x min(-1). Sample size was 10. Data was subjected to ANOVA and a post-hoc Tukey's test. The bond strength of amalgam to enamel was zero. The bond strength of the gallium-indium alloy ranged between 6.5 MPa (10s etch with 10% phosphoric acid) and 4.2 MPa (pumiced enamel). Acid-etching significantly increased the bond strength (P>0.0001) The bond strength was not significantly affected by the type of mechanical surface preparation, storage conditions, thermocycling, etching times or acid concentrations. Bonding, particularly chemical bonding, suggests a greater potential for better wetting and therefore better sealing of a cavity. Since microleakage of restorations is one of the principal causes of restoration failure, materials that can bond may in turn posses enhanced resistance to microleakage and ultimately, resistance to restoration failure. The gallium-indium alloy evaluated in this study may be such an alloy.

Effect of blood and saliva contamination on bond strength of brackets bonded with a protective liquid polish and a light-cured adhesive.

PubMed

Sayinsu, Korkmaz; Isik, Fulya; Sezen, Serdar; Aydemir, Bulent

2007-03-01

The application of a polymer coating to the labial enamel tooth surface before bonding can help keep white spot lesions from forming. Previous studies evaluating the effects of blood and saliva contamination on the bond strengths of light-cured composites showed significant reductions in bond strength values. The purpose of this study was to investigate whether the bond strength of a light-cured system (Transbond XT, 3M Unitek, Puchheim, Germany) used with a liquid polish (BisCover, Bisco, Schaumburg, Ill) is affected by contamination with blood or saliva. One hundred twenty permanent human premolars were randomly divided into 6 groups of 20. Various enamel surface conditions were studied: dry, blood contaminated, and saliva contaminated. A light-cured bonding system (Transbond XT) was used in all groups. The teeth in group 1 were bonded with Transbond XT. In the second group, BisCover polymeric resin polish was applied on the etched tooth surfaces before the brackets were bonded with Transbond XT resin. Comparison of the first and second groups showed no statistically significant difference. Groups 3 through 6 were bonded without Transbond XT. For groups 3 and 5, a layer of blood or saliva, respectively, was applied to the etched enamel followed by BisCover. In groups 4 and 6, blood or saliva, respectively, was applied on the light-cured BisCover. Shear forces were applied to the samples with a universal testing machine, and bond strengths were measured in megapascals. The protective liquid polish (BisCover) layer did not affect bond strength. Blood contamination on acid-etched surfaces affects bond strength more than saliva contamination. When a protective liquid polish (BisCover) is applied to the tooth surface, the effect of contamination by blood or saliva is prevented.

Accelerated aging of adhesive-mediated fiber post-resin composite bonds: A modeling approach.

PubMed

Radovic, Ivana; Monticelli, Francesca; Papacchini, Federica; Magni, Elisa; Cury, Alvaro Hafiz; Vulicevic, Zoran R; Ferrari, Marco

2007-08-01

Although fiber posts luted in root canals are not directly exposed to oral fluids, water storage is considered as in vitro accelerated aging test for bonded interfaces. The aim of the study was to evaluate the influence of accelerated water aging on fiber post-resin composite adhesion. Forty fiber posts (DT Light Post, RTD) were randomly divided into two main groups, according to the surface treatment performed. Group I: XPBond adhesive (Dentsply Caulk); Group II: sandblasting (Rocatec-Pre, 3M ESPE) and XPBond. Dual-cured resin cement (Calibra, Dentsply Caulk) and flowable composite (X-Flow, Dentsply Caulk) were applied on the posts to produce cylindrical specimens. The bond strength at the interface between post and cement/composite was measured with the microtensile test according to the non-trimming technique. Half of the sticks were tested immediately for bond strength, while in the other half testing was performed after 1 month of water storage at 37 degrees C. Post-cement/composite interfaces were evaluated under SEM prior and after water aging. Statistical analysis was performed using the Kruskal-Wallis ANOVA followed by Dunn's multiple range test (p<0.05). Immediate bond strength was higher on sandblasted posts. After water aging the two post surface treatments resulted comparable in bond strength. Resin cement achieved higher bond strength to fiber posts than flowable composite. Water aging significantly reduced bond strength. Sandblasting followed by adhesive coating may improve immediate post-resin bond strength in comparison to adhesive alone. However, fiber post-resin bond strength mediated by hydrophilic adhesive tends to decrease after water aging.

Effect of surface treatments on shear bond strength of resin composite bonded to CAD/CAM resin-ceramic hybrid materials

PubMed Central

Güngör, Merve Bankoğlu; Bal, Bilge Turhan; Ünver, Senem; Doğan, Aylin

2016-01-01

PURPOSE The purpose of this study was to assess the effect of surface treatments on shear bond strength of resin composite bonded to thermocycled and non-thermocycled CAD/CAM resin-ceramic hybrid materials. MATERIALS AND METHODS 120 specimens (10×10×2 mm) from each material were divided into 12 groups according to different surface treatments in combination with thermal aging procedures. Surface treatment methods were airborne-particle abrasion (abraded with 50 micron alumina particles), dry grinding (grinded with 125 µm grain size bur), and hydrofluoric acid (9%) and silane application. According to the thermocycling procedure, the groups were assigned as non-thermocycled, thermocycled after packing composites, and thermocycled before packing composites. The average surface roughness of the non-thermocycled specimens were measured after surface treatments. After packing composites and thermocycling procedures, shear bond strength (SBS) of the specimens were tested. The results of surface roughness were statistically analyzed by 2-way Analysis of Variance (ANOVA), and SBS results were statistically analyzed by 3-way ANOVA. RESULTS Surface roughness of GC were significantly lower than that of LU and VE (P<.05). The highest surface roughness was observed for dry grinding group, followed by airborne particle abraded group (P<.05). Comparing the materials within the same surface treatment method revealed that untreated surfaces generally showed lower SBS values. The values of untreated LU specimens showed significantly different SBS values compared to those of other surface treatment groups (P<.05). CONCLUSION SBS was affected by surface treatments. Thermocycling did not have any effect on the SBS of the materials except acid and silane applied GC specimens, which were subjected to thermocycling before packing of the composite resin. PMID:27555894

Shear Bond Strength of Orthodontic Brackets to Tooth Enamel After Treatment With Different Tooth Bleaching Methods.

PubMed

Vahid Dastjerdi, Elahe; Khaloo, Negar; Mojahedi, Seyed Masoud; Azarsina, Mohadese

2015-11-01

Bleaching treatments decrease shear bond strength between orthodontic brackets and teeth; although definite results have not been reported in this regard. This study determined the effects of different bleaching protocols on the shear bond strength of orthodontic brackets to teeth. This experimental study was performed in Iran. Forty-eight extracted human premolars were randomly assigned into four groups. In the control group, no bleaching treatment was performed. In groups 2 - 4, the bleaching procedures were performed using carbamide peroxide 45%, carbamide peroxide 20% and diode laser, respectively. Two weeks later, brackets were bonded to teeth and thermocycled. The shear bond strengths of the brackets to the teeth were measured. Data was analyzed by one-way ANOVA and Dunnett post-hoc test. Shear bond strength of the brackets to the teeth were 10.54 ± 1.51, 6.37 ± 0.92, 7.67 ± 1.01 and 7.49 ± 1.19 MPa, in groups 1 - 4, respectively. Significant differences were found between control group and all other groups (P < 0.001); and also between groups 2 and 3 (P < 0.05). No significant differences were found between the other groups. The bleaching procedures using 20% carbamide peroxide and 45% carbamide peroxide and diode laser significantly decreased shear bond strength of brackets to the teeth. 45% carbamide peroxide had a more significant effect on bond strength compared to 20% carbamide peroxide. The difference in bond strength was not significant between laser group and either carbamide peroxide groups.

Comparison between universal adhesives and two-step self-etch adhesives in terms of dentin bond fatigue durability in self-etch mode.

PubMed

Tsujimoto, Akimasa; Barkmeier, Wayne W; Takamizawa, Toshiki; Watanabe, Hidehiko; Johnson, William W; Latta, Mark A; Miyazaki, Masashi

2017-06-01

This aim of this study was to compare universal adhesives and two-step self-etch adhesives in terms of dentin bond fatigue durability in self-etch mode. Three universal adhesives - Clearfil Universal, G-Premio Bond, and Scotchbond Universal Adhesive - and three-two-step self-etch adhesives - Clearfil SE Bond, Clearfil SE Bond 2, and OptiBond XTR - were used. The initial shear bond strength and shear fatigue strength of resin composite bonded to adhesive on dentin in self-etch mode were determined. Scanning electron microscopy observations of fracture surfaces after bond strength tests were also made. The initial shear bond strength of universal adhesives was material dependent, unlike that of two-step self-etch adhesives. The shear fatigue strength of Scotchbond Universal Adhesive was not significantly different from that of two-step self-etch adhesives, unlike the other universal adhesives. The shear fatigue strength of universal adhesives differed depending on the type of adhesive, unlike those of two-step self-etch adhesives. The results of this study encourage the continued use of two-step self-etch adhesive over some universal adhesives but suggest that changes to the composition of universal adhesives may lead to a dentin bond fatigue durability similar to that of two-step self-etch adhesives. © 2017 Eur J Oral Sci.

Comparing the shear bond strength of direct and indirect composite inlays in relation to different surface conditioning and curing techniques

PubMed Central

Zorba, Yahya Orcun; Ilday, Nurcan Ozakar; Bayındır, Yusuf Ziya; Demirbuga, Sezer

2013-01-01

Objective: The aim of this study was to test the null hypothesis that different surface conditioning (etch and rinse and self-etch) and curing techniques (light cure/dual cure) had no effect on the shear bond strength of direct and indirect composite inlays. Materials and Methods: A total of 112 extracted human molar teeth were horizontally sectioned and randomly divided into two groups according to restoration technique (direct and indirect restorations). Each group was further subdivided into seven subgroups (n = 8) according to bonding agent (etch and rinse adhesives Scotchbond multi-purpose plus, All-Bond 3, Adper Single Bond and Prime Bond NT; and self-etch adhesives Clearfil Liner Bond, Futurabond DC and G bond). Indirect composites were cemented to dentin surfaces using dual-curing luting cement. Shear bond strength of specimens was tested using a Universal Testing Machine. Two samples from each subgroup were evaluated under Scanning electron microscopy to see the failing modes. Data was analyzed using independent sample t-tests and Tukey's tests. Results: Surface conditioning and curing of bonding agents were all found to have significant effects on shear bond strength (P < 0.05) of both direct and indirect composite inlays. With direct restoration, etch and rinse systems and dual-cured bonding agents yielded higher bond strengths than indirect restoration, self-etch systems and light-cured bonding agents. Conclusions: The results of the present study indicated that direct restoration to be a more reliable method than indirect restoration. Although etch and rinse bonding systems showed higher shear bond strength to dentin than self-etch systems, both systems can be safely used for the adhesion of direct as well as indirect restorations. PMID:24932118

Comparing the shear bond strength of direct and indirect composite inlays in relation to different surface conditioning and curing techniques.

PubMed

Zorba, Yahya Orcun; Ilday, Nurcan Ozakar; Bayındır, Yusuf Ziya; Demirbuga, Sezer

2013-10-01

The aim of this study was to test the null hypothesis that different surface conditioning (etch and rinse and self-etch) and curing techniques (light cure/dual cure) had no effect on the shear bond strength of direct and indirect composite inlays. A total of 112 extracted human molar teeth were horizontally sectioned and randomly divided into two groups according to restoration technique (direct and indirect restorations). Each group was further subdivided into seven subgroups (n = 8) according to bonding agent (etch and rinse adhesives Scotchbond multi-purpose plus, All-Bond 3, Adper Single Bond and Prime Bond NT; and self-etch adhesives Clearfil Liner Bond, Futurabond DC and G bond). Indirect composites were cemented to dentin surfaces using dual-curing luting cement. Shear bond strength of specimens was tested using a Universal Testing Machine. Two samples from each subgroup were evaluated under Scanning electron microscopy to see the failing modes. Data was analyzed using independent sample t-tests and Tukey's tests. Surface conditioning and curing of bonding agents were all found to have significant effects on shear bond strength (P < 0.05) of both direct and indirect composite inlays. With direct restoration, etch and rinse systems and dual-cured bonding agents yielded higher bond strengths than indirect restoration, self-etch systems and light-cured bonding agents. The results of the present study indicated that direct restoration to be a more reliable method than indirect restoration. Although etch and rinse bonding systems showed higher shear bond strength to dentin than self-etch systems, both systems can be safely used for the adhesion of direct as well as indirect restorations.

Shear bond strengths of an indirect composite layering material to a tribochemically silica-coated zirconia framework material.

PubMed

Iwasaki, Taro; Komine, Futoshi; Fushiki, Ryosuke; Kubochi, Kei; Shinohara, Mitsuyo; Matsumura, Hideo

2016-01-01

This study evaluated shear bond strengths of a layering indirect composite material to a zirconia framework material treated with tribochemical silica coating. Zirconia disks were divided into two groups: ZR-PRE (airborne-particle abrasion) and ZR-PLU (tribochemical silica coating). Indirect composite was bonded to zirconia treated with one of the following primers: Clearfil Ceramic Primer (CCP), Clearfil Mega Bond Primer with Clearfil Porcelain Bond Activator (MGP+Act), ESPE-Sil (SIL), Estenia Opaque Primer, MR. Bond, Super-Bond PZ Primer Liquid A with Liquid B (PZA+PZB), and Super-Bond PZ Primer Liquid B (PZB), or no treatment. Shear bond testing was performed at 0 and 20,000 thermocycles. Post-thermocycling shear bond strengths of ZR-PLU were higher than those of ZR-PRE in CCP, MGP+Act, SIL, PZA+PZB, and PZB groups. Application of silane yielded better durable bond strengths of a layering indirect composite material to a tribochemically silica-coated zirconia framework material.

Effect of Two-minute Application of 35% Sodium Ascorbate on Composite Bond Strength following Bleaching.

PubMed

Ismail, Eman H; Kilinc, Evren; Hardigan, Patrick C; Rothrock, James K; Thompson, Jeffrey Y; Garcia-Godoy, Cristina

2017-10-01

The aim of this study is to assess the effect of 35% sodium ascorbate on microtensile bond strength of dentin immediately after bleaching with 35% hydrogen peroxide. A total of 25 sound human 3 rd molars were collected. Teeth were randomly divided into five groups for different treatments: Group I [bleaching + immediate bonding (i.e., restoration)], group II (bleaching + delayed bonding), group III (bleaching + sodium ascorbate + immediate bonding), group IV (bleaching + sodium ascorbate + delayed bonding), and group V (bonding only). After bleaching, but before bonding, groups II and IV were stored for 1 week in deionized water at 37°C. All samples were bonded using OptiBoned FL (Kerr) and Filtek Supreme (3M/ESPE). Teeth were sectioned into 1 × 1 mm 2 bars, and microtensile bond strength was tested with a universal testing machine (Instron 8841) at a cross-head speed of 0.5 mm/minute. Microtensile bond strength differed significantly across the five groups, with a significant reduction in microtensile bond strength observed for samples in group I relative to samples in any of the other treatment groups (p < 0.05). The application of a high concentration of sodium ascorbate for a shorter time reversed the negative effect of 35% hydrogen peroxide bleaching on composite bonding strength to dentin. The negative effects of bleaching on composite bonding can be neutralized by the application of the reversing agent sodium ascorbate thus, increasing the efficiency of clinic chair time. This is clinically relevant for those patients requiring restorative treatment immediately after in-office bleaching.

Bond strength of metal brackets bonded to a silica-based ceramic with light-cured adhesive : Influence of various surface treatment methods.

PubMed

Zhang, Zhe-Chen; Qian, Yu-Fen; Yang, Yi-Ming; Feng, Qi-Ping; Shen, Gang

2016-09-01

The purpose of this work was to evaluate the effects of several surface treatment methods on the shear bond strengths of metal brackets bonded to a silica-based ceramic with a light-cured adhesive. Silica-based ceramic (IPS Classic(®)) with glazed surfaces was cut into discs that were used as substrates. A total of 80 specimens were randomly divided into four groups according to the method used: 9.6 % hydrofluoric acid (group 1), 9.6 % hydrofluoric acid (HF) + silane coupling agent (group 2), sandblasting (aluminum trioxide, 50 μm) + silane (group 3), and tribochemical silica coating (CoJet™ sand, 30 μm) + silane (group 4). Brackets were bonded to the treated specimens with a light-cure adhesive (Transbond XT, 3 M Unitek). Shear bond strength was tested after bracket bonding, and the Adhesive Remnant Index (ARI) scores were quantified after debonding. Group 4 showed the highest bond strength (12.3 ± 1.0 MPa), which was not significantly different from that of group 3 (11.6 ± 1.2 MPa, P > 0.05); however, the bond strength of group 4 was substantially higher than that of group 2 (9.4 ± 1.1 MPa, P < 0.05). The shear bond strength of group 1 (3.1 ± 0.6 MPa, P< 0.05) was significantly lower than that of the other groups. Shear bond strengths exceeded the optimal range of ideal bond strength for clinical practice, except for the isolated HF group. HF acid etching followed by silane was the best suited method for bonding on IPS Classic(®). Failure modes in the sandblasting and silica-coating groups revealed signs of damaged ceramic surfaces.

Microstructural and Mechanical Properties of Hot Roll Bonded Titanium Alloy/Low Carbon Steel Plate

NASA Astrophysics Data System (ADS)

Yu, Chao; Qi, Zi-chen; Yu, Hui; Xu, Cheng; Xiao, Hong

2018-03-01

In this paper, a titanium alloy and low carbon steel were bonded via hot rolling in a vacuum, and the effect of roll bonding temperature and reduction ratio on the microstructural and mechanical properties of the plate was studied. When the bonding temperature was between 850 and 1050 °C, the shear strength of the interface increased with an increasing reduction ratio from 18 to 70%. At a bonding temperature of 950 °C and at a rolling reduction ratio of 70%, the best bonding strength was obtained, and a shear fracture occurred on the low carbon steel matrix. At 1050 °C, brittle compounds, i.e., TiC, FeTi, and Fe2Ti, formed at the interface, which decreased the bonding strength. The large reduction ratio can break up compounds at the interface and extrude fresh metal for bonding, thereby increasing the bonding strength.

Effect of light aging on silicone-resin bond strength in maxillofacial prostheses.

PubMed

Polyzois, Gregory; Pantopoulos, Antonis; Papadopoulos, Triantafillos; Hatamleh, Muhanad

2015-04-01

The aim of this study was to investigate the effect of accelerated light aging on bond strength of a silicone elastomer to three types of denture resin. A total of 60 single lap joint specimens were fabricated with auto-, heat-, and photopolymerized (n = 20) resins. An addition-type silicone elastomer (Episil-E) was bonded to resins treated with the same primer (A330-G). Thirty specimens served as controls and were tested after 24 hours, and the remaining were aged under accelerated exposure to daylight for 546 hours (irradiance 765 W/m(2) ). Lap shear joint tests were performed to evaluate bond strength at 50 mm/min crosshead speed. Two-way ANOVA and Tukey's test were carried out to detect statistical significance (p < 0.05). ANOVA showed that the main effect of light aging was the most important factor determining the shear bond strength. The mean bond strength values ranged from 0.096 to 0.136 MPa. The highest values were recorded for auto- (0.131 MPa) and photopolymerized (0.136 MPa) resins after aging. Accelerated light aging for 546 hours affects the bond strength of an addition-type silicone elastomer to three different denture resins. The bond strength significantly increased after aging for photo- and autopolymerized resins. All the bonds failed adhesively. © 2014 by the American College of Prosthodontists.

Comparison of shear bond strength of brackets recycled using micro sandblasting and industrial methods.

PubMed

Montero, Manuela M Haro; Vicente, Ascensión; Alfonso-Hernández, Noelia; Jiménez-López, Manuel; Bravo-González, Luis-Alberto

2015-05-01

To evaluate in vitro the shear bond strength of brackets recycled by sandblasting with aluminum oxide particles of different sizes or reconditioned industrially after successive rebonding. Eighty brackets were bonded and debonded sequentially three times. After the first debonding, brackets were divided into four groups: (group 1) sandblasting with aluminum oxide particles of 25 μ, (group 2) 50 μ, and (group 3) 110 μ, and (group 4) industrial recycling. Bond strength and adhesive material remaining on debonded bracket bases were evaluated for each successive debond. No significant differences were detected between the four groups following the first recycle (P > .05). After the second recycle, bond strength was significantly greater for the industrially recycled group than the other groups (P < .016). When shear bond strength was compared within each recycling method, the bond strength of sandblasted brackets decreased with the increase of particle size and with each recycle; for the industrially recycled group, no significant differences were detected between the three sequences (P > .016). In the evaluation of bond material remnant, the industrially recycled group left significantly less bond material after successive recycling than the other groups did (P < .016). Within each recycling method, the adhesive remnant decreased significantly after successive debond (P < .016). Industrial recycling obtained better results than sandblasting after three successive debondings. The brackets' shear bond strength decreased as the size of the aluminum oxide particle used for sandblasting increased and as recycling was repeated.

Shear bond strength of computer-aided design and computer-aided manufacturing feldspathic and nano resin ceramics blocks cemented with three different generations of resin cement.

PubMed

Ab-Ghani, Zuryati; Jaafar, Wahyuni; Foo, Siew Fon; Ariffin, Zaihan; Mohamad, Dasmawati

2015-01-01

To evaluate the shear bond strength between the dentin substrate and computer-aided design and computer-aided manufacturing feldspathic ceramic and nano resin ceramics blocks cemented with resin cement. Sixty cuboidal blocks (5 mm × 5 mm × 5 mm) were fabricated in equal numbers from feldspathic ceramic CEREC(®) Blocs PC and nano resin ceramic Lava™ Ultimate, and randomly divided into six groups (n = 10). Each block was cemented to the dentin of 60 extracted human premolar using Variolink(®) II/Syntac Classic (multi-steps etch-and-rinse adhesive bonding), NX3 Nexus(®) (two-steps etch-and-rinse adhesive bonding) and RelyX™ U200 self-adhesive cement. All specimens were thermocycled, and shear bond strength testing was done using the universal testing machine at a crosshead speed of 1.0 mm/min. Data were analyzed using one-way ANOVA. Combination of CEREC(®) Blocs PC and Variolink(®) II showed the highest mean shear bond strength (8.71 Mpa), while the lowest of 2.06 Mpa were observed in Lava™ Ultimate and RelyX™ U200. There was no significant difference in the mean shear bond strength between different blocks. Variolink(®) II cement using multi-steps etch-and-rinse adhesive bonding provided a higher shear bond strength than the self-adhesive cement RelyX U200. The shear bond strength was not affected by the type of blocks used.

The effect of grinding and/or airborne-particle abrasion on the bond strength between zirconia and veneering porcelain: a systematic review

PubMed Central

Lundberg, Karin; Wu, Lindsey; Papia, Evaggelia

2017-01-01

Abstract Objective: The aim of the study was to make an inventory of current literature on the bond strength between zirconia and veneering porcelain after surface treatment of zirconia by grinding with diamond bur and/or with airborne-particle abrasion. Material and methods: The literature search for the present review was made following recommended guidelines using acknowledged methodology on how to do a systematic review. The electronic databases PubMed, Cochrane Library, and Science Direct were used in the present study. Results: Twelve studies were selected. Test methods used in the original studies included shear bond strength (SBS) test, tensile bond strength test, and micro-tensile bond strength test. The majority of studies used SBS. Results showed a large variation within each surface treatment of zirconia, using different grain size, blasting time, and pressure. Conclusions: Airborne-particle abrasion might improve the bond strength and can therefore be considered a feasible surface treatment for zirconia that is to be bonded. Grinding has been recommended as a surface treatment for zirconia to improve the bond strength; however, this recommendation cannot be verified. A standardized test method and surface treatment are required to be able to compare the results from different studies and draw further conclusions. PMID:28642927

Shear bond strength of metallic and ceramic brackets using color change adhesives.

PubMed

Stumpf, Aisha de Souza Gomes; Bergmann, Carlos; Prietsch, José Renato; Vicenzi, Juliane

2013-01-01

To determine the shear bond strength of orthodontic brackets using color change adhesives that are supposed to aid in removing excess of bonding material and compare them to a traditional adhesive. Ninety metallic and ninety ceramic brackets were bonded to bovine incisors using two color change adhesives and a regular one. A tensile stress was applied by a universal testing machine. The teeth were observed in a microscope after debonding in order to determine the Adhesive Remnant Index (ARI). The statistical analysis (ANOVA, Tukey, and Kruskall-Wallis tests) demonstrated that the mean bond strength presented no difference when metallic and ceramic brackets were compared, but the bond resistance values were significantly different for the three adhesives used. The most common ARI outcome was the entire adhesive remaining on the enamel. The bond strength was similar for metallic and ceramic brackets when the same adhesive system was used. ARI scores demonstrated that bonding with these adhesives is safe even when ceramic brackets were used. On the other hand, bond strength was too low for orthodontic purposes when Ortho Lite Cure was used.

Comparison of bond strengths of ceramic brackets bonded to zirconia surfaces using different zirconia primers and a universal adhesive.

PubMed

Lee, Ji-Yeon; Ahn, Jaechan; An, Sang In; Park, Jeong-Won

2018-02-01

The aim of this study is to compare the shear bond strengths of ceramic brackets bonded to zirconia surfaces using different zirconia primers and universal adhesive. Fifty zirconia blocks (15 × 15 × 10 mm, Zpex, Tosoh Corporation) were polished with 1,000 grit sand paper and air-abraded with 50 µm Al 2 O 3 for 10 seconds (40 psi). They were divided into 5 groups: control (CO), Metal/Zirconia primer (MZ, Ivoclar Vivadent), Z-PRIME Plus (ZP, Bisco), Zirconia Liner (ZL, Sun Medical), and Scotchbond Universal adhesive (SU, 3M ESPE). Transbond XT Primer (used for CO, MZ, ZP, and ZL) and Transbond XT Paste was used for bracket bonding (Gemini clear ceramic brackets, 3M Unitek). After 24 hours at 37°C storage, specimens underwent 2,000 thermocycles, and then, shear bond strengths were measured (1 mm/min). An adhesive remnant index (ARI) score was calculated. The data were analyzed using one-way analysis of variance and the Bonferroni test ( p = 0.05). Surface treatment with primers resulted in increased shear bond strength. The SU group showed the highest shear bond strength followed by the ZP, ZL, MZ, and CO groups, in that order. The median ARI scores were as follows: CO = 0, MZ = 0, ZP = 0, ZL = 0, and SU = 3 ( p < 0.05). Within this experiment, zirconia primer can increase the shear bond strength of bracket bonding. The highest shear bond strength is observed in SU group, even when no primer is used.

Comparison of bond strengths of ceramic brackets bonded to zirconia surfaces using different zirconia primers and a universal adhesive

PubMed Central

2018-01-01

Objectives The aim of this study is to compare the shear bond strengths of ceramic brackets bonded to zirconia surfaces using different zirconia primers and universal adhesive. Materials and Methods Fifty zirconia blocks (15 × 15 × 10 mm, Zpex, Tosoh Corporation) were polished with 1,000 grit sand paper and air-abraded with 50 µm Al2O3 for 10 seconds (40 psi). They were divided into 5 groups: control (CO), Metal/Zirconia primer (MZ, Ivoclar Vivadent), Z-PRIME Plus (ZP, Bisco), Zirconia Liner (ZL, Sun Medical), and Scotchbond Universal adhesive (SU, 3M ESPE). Transbond XT Primer (used for CO, MZ, ZP, and ZL) and Transbond XT Paste was used for bracket bonding (Gemini clear ceramic brackets, 3M Unitek). After 24 hours at 37°C storage, specimens underwent 2,000 thermocycles, and then, shear bond strengths were measured (1 mm/min). An adhesive remnant index (ARI) score was calculated. The data were analyzed using one-way analysis of variance and the Bonferroni test (p = 0.05). Results Surface treatment with primers resulted in increased shear bond strength. The SU group showed the highest shear bond strength followed by the ZP, ZL, MZ, and CO groups, in that order. The median ARI scores were as follows: CO = 0, MZ = 0, ZP = 0, ZL = 0, and SU = 3 (p < 0.05). Conclusions Within this experiment, zirconia primer can increase the shear bond strength of bracket bonding. The highest shear bond strength is observed in SU group, even when no primer is used. PMID:29487838

An Investigation of Armenite, BaCa2Al6Si9O302H2O.H2O Molecules and H Bonding in Microporous Silicates

NASA Astrophysics Data System (ADS)

Geiger, C. A.; Gatta, G.; Xue, X.; McIntyre, G.

2012-12-01

The crystal chemistry of armenite, ideally BaCa2Al6Si9O30.2H2O, a double-ring structure belonging to the milarite group, was studied to better understand the nature of extra-framework "Ca-oxygen-anion-H2O-molecule quasi-clusters" and H bonding behavior in microporous silicates. Neutron and X-ray single-crystal diffraction and IR powder and 1H NMR spectroscopic measurements were made. Four crystallographically independent Ca and H2O molecule sites were refined from the diffraction data, whereby both sites appear to have partial occupancies such that locally a Ca atom can have only a single H2O molecule bonded to it through an ion-dipole interaction. The Ca cation is further bonded to six O atoms of the framework forming a quasi cluster around it. The neutron results give the first static description of the protons in armenite, allowing bond distances and angles relating to the H2O molecules and H bonds to be determined. The IR spectrum of armenite is characterized in the OH-stretching region at RT by two broad bands at roughly 3470 and 3410 cm-1 and by a single H2O bending mode at 1654 cm-1. At 10 K four intense OH bands are located at 3479, 3454, 3401 and 3384 cm-1 and two H2O bending modes at 1650 and 1606 cm-1. The 1H MAS NMR spectrum shows a single strong resonance near 5.3 ppm and a smaller one near 2.7 ppm. The former can be assigned to H2O molecules bonded to Ca and the latter to weakly bonded H2O located at a site at the center of the structural double ring and it is partially occupied. The nature of H bonding in the microporous Ca-bearing zeolites scolecite, wairakite and epistilbite are also analyzed. The average OH stretching wavenumber shown by the IR spectra of armenite (~3435 cm-1) and scolecite (~3430 cm-1) are similar, while the average OH wavenumbers for wairakite (~3475 cm-1) and epistilbite (~3500 cm-1) are greater. In all cases the average OH stretching wavenumber is more similar to that of liquid water (~3400 cm-1) than of ice (~3220 cm-1). The strength of hydrogen bonding of the H2O molecules in microporous silicates does not appear to change greatly with decreasing temperatures from 300 K down to 10 K. The reason for this and also understanding better the ion-dipole interaction and its effect on H-bonding strength in Ca-quasi clusters need further study. The crystal structure of armenite viewed down [001] and [010].

Effect of a whitening agent application on enamel bond strength of self-etching primer systems.

PubMed

Miyazaki, Masashi; Sato, Hikaru; Sato, Tomomi; Moore, B Keith; Platt, Jeffrey A

2004-06-01

Though reduction in bond strength after tooth whitening has been reported, little is known about it's effect on enamel bond strength of two-step bonding systems that exclude phosphoric acid etching prior to bonding agent application. The purpose of this study was to determine the effect of whitening procedure using an in-office whitening agent on enamel bond strength of self-etching primer systems. Three self-etching primer systems, Imperva Fluoro Bond, Mac Bond II, Clearfil SE Bond, and a one-bottle adhesive system Single Bond as a control material, were used. Bovine mandibular incisors were mounted in self-curing resin and the facial enamel or dentin surfaces were ground wet on 600-grit SiC paper. An in-office whitening agent, Hi-Lite was applied on the tooth surface according to the manufacturer's instruction. Bonding procedures were done soon after rinsing off the whitening agent or after 24 hours storage in distilled water. Specimens without whitening procedure were prepared as controls. Fifteen specimens per test group were stored in 37 degrees C distilled water for 24 hours, then shear tested at a crosshead speed of 1.0 mm/minute. One-way ANOVA followed by Duncan multiple range test were used for statistical analysis of the results. For the specimens made soon after rinsing off the whitening agent, a significant decrease in enamel bond strength was observed for all the bonding systems used. For the specimens made after 24 hours storage in water, a small decrease in enamel bond strength was observed and no significant differences were found compared to those of controls (without whitening). From the results of this study, enamel bond strengths of the self-etching primer systems might be affected to a lesser degree after rinsing with water followed by 24 hours storage in water.

Evaluating the shear bond strength of enamel and dentin with or without etching: A comparative study between dimethacrylate-based and silorane-based adhesives

PubMed Central

Hajizadeh, Hila; Nasseh, Atefeh; Rahmanpour, Naim

2015-01-01

Background Silorane-based composites and their specific self-etch adhesive were introduced to conquest the polymerization shrinkage of methacrylate-based composites. It has been shown that additional etching of enamel and dentin can improve the bond strength of self-etch methacrylate-based adhesives but this claim is not apparent about silorane-based adhesives. Our objective was to compare the shear bond strength (SBS) of enamel and dentin between silorane-based adhesive resin and a methacrylate-based resin with or without additional etching. Material and Methods 40 sound human premolars were prepared and divided into two groups: 1- Filtek P60 composite and Clearfil SE Bond adhesive; 2- Filtek P90 composite and Silorane adhesive. Each group divided into two subgroups: with or without additional etching. For additional etching, 37% acid phosphoric was applied before bonding procedure. A cylinder of the composite was bonded to the surface. After 24 hours storage and 500 thermo cycling between 5-55°C, shear bond strength was assessed with the cross head speed of 0.5 mm/min. Then, bonded surfaces were observed under stereomicroscope to determine the failure mode. Data were analyzed with two-way ANOVA and Fischer exact test. Results Shear bond strength of Filtek P60 composite was significantly higher than Filtek P90 composite both in enamel and dentin surfaces (P<0.05). However, additional etching had no significant effect on shear bond strength in enamel or dentin for each of the composites (P>0.05). There was no interaction between composite type and additional etching (P>0.05). Failure pattern was mainly adhesive and no significant correlation was found between failure and composite type or additional etching (P>0.05). Conclusions Shear bond strength of methacrylate-based composite was significantly higher than silorane-based composite both in enamel and dentin surfaces and additional etching had no significant effect on shear bond strength in enamel or dentin for each of the composites. The mode of failure had no meaningful relation to the type of composite and etching factor. Key words:Shear bond strength, adhesive, composite resin, silorane, methacrylate. PMID:26644830

Effects of Universal and Conventional MDP Primers on the Shear Bond Strength of Zirconia Ceramic and Nanofilled Composite Resin

PubMed Central

Sharafeddin, Farahnaz; Shoale, Soodabe

2018-01-01

Statement of the Problem: The clinical success of ceramic depends on the quality of the bond between the zirconia and resin cement. Purpose: In the present study, the effects of universal and conventional MDP-containing primers were evaluated on the shear bond strength of zirconia ceramic and nanofilled composite resin. Materials and Method: Thirty blocks of zirconia ceramic (6mm×2mm) were prepared. Then the inner surfaces were air-abraded and divided into three groups (n= 10) as follows: untreated with primer (control group, I); All- Bond Universal (group II) and Z-Prime Plus (group III). The specimens in each group were bonded with Variolink N cement to cylinders of composite resin Z350XT. After 24 hour water storage, the shear bond strength test was performed with a universal testing machine at a crosshead speed of 1mm/ min and bond strength values (MPa) were calculated and analyzed with one-way ANOVA and post hoc Tukey tests (p< 0.05). The failure mode of each specimen was evaluated under a stereomicroscope and representative specimens were analyzed by scanning electron microscopy (SEM). Results: The mean shear bond strength values (MPa) were 7.58±1.62, 17.51±1.34 and 22.45±3.60 in groups I, II and III, respectively. These results indicated that the shear bond strength were significantly higher in groups II and III compared to the control group (p< 0.001). Chemical pre-treatment of zirconia with Z- Prime Plus revealed significantly higher bond strength than the All-Bond Universal adhesive (p< 0.002). All the failure modes were adhesive in the control group (I) and when using primer treatment, mixed failures occurred in 40% and 50% of specimens in groups II and III, respectively. Conclusion: Treatment with both primers resulted in higher bond strength values compared to the control group. The use of Z-Prime Plus treatment in combination with air-abrasion procedure resulted in the highest bond strength. PMID:29492416

Effect of laser welding on the titanium composite tensile bond strength.

PubMed

Galo, Rodrigo; Ribeiro, Ricardo Faria; Rodrigues, Renata Cristina Silveira; Pagnano, Valéria de Oliveira; de Mattos, Maria da Glória Chiarello

2009-01-01

The aim of this study was to analyze the shear bond strength between commercially pure titanium, with and without laser welding, after airbone-particle abrasion (Al(2)O(3)) and 2 indirect composites. Sixty-four specimens were cast and divided into 2 groups with and without laser welding. Each group was divided in 4 subgroups, related to Al(2)O(3) grain size: A - 250 microm; B - 180 microm; C- 110 microm; and D - 50 microm. Composite rings were formed around the rods and light polymerized using UniXS unit. Specimens were invested and their shear bond strength at failure was measured with a universal testing machine at a crosshead speed of 2.0 mm/min. Statistical analysis was carried out with ANOVA and Tukey's test (alpha=0.05). The highest bond strength means were recorded in 250 microm group without laser welding. The lowest shear bond strength means were recorded in 50 microm group with laser welding. Statistically significant differences (p<0.05) were found between all groups. In conclusion, airborne particle abrasion yielded significantly lower bond strength as the Al(2)O(3) particle size decreased. Shear bond strength decreased in the laser welded specimens.

Shear Bond Strength of Orthodontic Brackets and Disinclusion Buttons: Effect of Water and Saliva Contamination

PubMed Central

Sfondrini, Maria Francesca; Fraticelli, Danilo; Gandini, Paola

2013-01-01

Purpose. The aim of this study was to assess the effect of water and saliva contamination on the shear bond strength and failure site of orthodontic brackets and lingual buttons. Materials and Methods. 120 bovine permanent mandibular incisors were randomly divided into 6 groups of 20 specimens each. Both orthodontic brackets and disinclusion buttons were tested under three different enamel surface conditions: (a) dry, (b) water contamination, and (c) saliva contamination. Brackets and buttons were bonded to the teeth and subsequently tested using a Instron universal testing machine. Shear bond strength values and adhesive failure rate were recorded. Statistical analysis was performed using ANOVA and Tukey tests (strength values) and Chi squared test (ARI Scores). Results. Noncontaminated enamel surfaces showed the highest bond strengths for both brackets and buttons. Under water and saliva contamination orthodontic brackets groups showed significantly lower shear strengths than disinclusion buttons groups. Significant differences in debond locations were found among the groups under the various enamel surface conditions. Conclusions. Water and saliva contamination of enamel during the bonding procedure lowers bond strength values, more with orthodontic brackets than with disinclusion buttons. PMID:23762825

Effect of Sandblasting and Type of Cement on the Bond Strength of Molar Bands on Stainless Steel Crowns.

PubMed

Bawazir, Omar A; Elaraby, Alaa; Alshamrani, Hamed; Salama, Fouad S

2015-01-01

The purposes of this study were to: (1) compare the bond strength of molar bands cemented to stainless steel crowns (SSCs) using glass ionomer cement (GIC), resin-modified glass ionomer cement (RMGIC), or polycarboxylate cement (PXC); and (2) assess the influence of sandblasting molar bands on the mean bond strength between the band and the SSC. Sixty SSCs and 60 molar bands were used. The inner surfaces of 30 molar bands were roughened by sandblasting prior to cementation. The bond strength was measured after dislodging the SSC using a push-out test. In the nonsandblasted group, a significant difference was observed between PXC and RMGIC (P >.04). In the sandblasted group, a significant difference was observed between PXC and RMGIC (P >.02), while there was only a marginal difference between GIC and RMGIC (P >.05). The sandblasted group exhibited superior bond strength overall. However, the only significant improvement was observed for GIC (P >.03). PXC showed the highest bond strength of molar bands to SSCs, while RMGIC showed the lowest. Sandblasting the inner surface of bands enhanced the bond strength of different cements.

An evaluation of shear bond strength of self-etch adhesive on pre-etched enamel: an in vitro study.

PubMed

Rao, Bhadra; Reddy, Satti Narayana; Mujeeb, Abdul; Mehta, Kanchan; Saritha, G

2013-11-01

To determine the shear bond strength of self-etch adhesive G-bond on pre-etched enamel. Thirty caries free human mandibular premolars extracted for orthodontic purpose were used for the study. Occlusal surfaces of all the teeth were flattened with diamond bur and a silicon carbide paper was used for surface smoothening. The thirty samples were randomly grouped into three groups. Three different etch systems were used for the composite build up: group 1 (G-bond self-etch adhesive system), group 2 (G-bond) and group 3 (Adper single bond). Light cured was applied for 10 seconds with a LED unit for composite buildup on the occlusal surface of each tooth with 8 millimeters (mm) in diameter and 3 mm in thickness. The specimens in each group were tested in shear mode using a knife-edge testing apparatus in a universal testing machine across head speed of 1 mm/ minute. Shear bond strength values in Mpa were calculated from the peak load at failure divided by the specimen surface area. The mean shear bond strength of all the groups were calculated and statistical analysis was carried out using one-way Analysis of Variance (ANOVA). The mean bond strength of group 1 is 15.5 Mpa, group 2 is 19.5 Mpa and group 3 is 20.1 Mpa. Statistical analysis was carried out between the groups using one-way ANOVA. Group 1 showed statistically significant lower bond strength when compared to groups 2 and 3. No statistical significant difference between groups 2 and 3 (p < 0.05). Self-etch adhesive G-bond showed increase in shear bond strength on pre-etched enamel.

Role of Hydrogen Bonding on Nonlinear Mechano-Optical Behavior of L-Phenylalanine-based Poly(ester urea)s.

NASA Astrophysics Data System (ADS)

Chen, Keke; Yu, Jiayi; Guzman, Gustavo; Es-Haghi, S. Shams; Becker, Matthew L.; Cakmak, Miko

The uniaxial mechano-optical behavior of a series of amorphous L-phenylalanine-based poly(ester urea) (PEU) films was studied in the rubbery state using a custom real-time measurement system. When the materials were subjected to deformation at temperatures near the glass transition temperature (Tg) , the photoelastic behavior was manifested by a small increase in birefringence with a significant increase in true stress. At temperatures above Tg, PEUs with a shorter diol chain length exhibited a liquid-liquid (Tll) transition at about 1.06 Tg (K), above which the material transforms from a heterogeneous ``liquid of fixed-structure'' to a ``true liquid'' state. The initial photoelastic behavior disappears with increasing temperature, as the initial slope of the stress optical curves becomes temperature independent. Fourier transform infrared spectra of PEUs revealed that the average strength of hydrogen bonding diminishes with increasing temperature. For PEUs with the longest diol chain length, the area associated with N-H stretching region exhibits a linear temperature dependence. The presence of hydrogen bonding enhances the ``stiff'' segmental correlations between adjacent chains in the PEU structure. As a result, the photoelastic constant decreases with increasing hydrogen bonding strength. This work was supported by the Ohio Department of Development's Innovation Platform Program and The National Science Foundation.

Enamel Wetness Effects on Microshear Bond Strength of Different Bonding Agents (Adhesive Systems): An in vitro Comparative Evaluation Study.

PubMed

Kulkarni, Girish; Mishra, Vinay K

2016-05-01

The purpose of this study was to compare the effect of enamel wetness on microshear bond strength using different adhesive systems. To evaluate microshear bond strength of three bonding agents on dry enamel; to evaluate microshear bond strength of three bonding agents on wet enamel; and to compare microshear bond strength of three different bonding agents on dry and wet enamel. Sixty extracted noncarious human premolars were selected for this study. Flat enamel surfaces of approximately 3 mm were obtained by grinding the buccal surfaces of premolars with water-cooled diamond disks. This study evaluated one etch-and-rinse adhesive system (Single Bond 2) and two self-etching adhesive systems (Clearfil SE Bond and Xeno-V). The specimens were divided into two groups (n = 30). Group I (dry) was air-dried for 30 seconds and in group II (wet) surfaces were blotted with absorbent paper to remove excess water. These groups were further divided into six subgroups (n = 10) according to the adhesives used. The resin composite, Filtek Z 250, was bonded to flat enamel surfaces that had been treated with one of the adhesives, following the manufacturer's instructions. After being stored in water at 37°C for 24 hours, bonded specimens were stressed in universal testing machine (Fig. 3) at a crosshead speed of 1 mm/min. The data were evaluated with one-way and two-way analysis of variance (ANOVA), t-test, and Tukey's Multiple Post hoc tests (a = 0.05). The two-way ANOVA and Tukey's Multiple Post hoc tests showed significant differences among adhesive systems, but wetness did not influence microshear bond strength (p = 0.1762). The one-way ANOVA and t-test showed that the all-in-one adhesive (Xeno-V) was the only material influenced by the presence of water on the enamel surface. Xeno-V showed significantly higher microshear bond strength when the enamel was kept wet. Single Bond 2 adhesive showed significantly higher microshear bond strength as compared with Xeno-V adhesive but no significant difference when compared with Clearfil SE Bond adhesive in dry enamel. Single Bond 2 adhesive showed no significant difference in microshear bond strength as compared with self-etching adhesive systems (Clearfil SE Bond and Xeno-V), when the enamel was kept wet. From the findings of the results, it was concluded that self-etching adhesives were not negatively affected by the presence of water on the enamel surface. The all-in-one adhesive showed different behavior depending on whether the enamel surface was dry or wet. So the enamel surface should not be desiccated, when self-etching adhesives are used.

Orthodontic bracket bonding without previous adhesive priming: A meta-regression analysis.

PubMed

Altmann, Aline Segatto Pires; Degrazia, Felipe Weidenbach; Celeste, Roger Keller; Leitune, Vicente Castelo Branco; Samuel, Susana Maria Werner; Collares, Fabrício Mezzomo

2016-05-01

To determine the consensus among studies that adhesive resin application improves the bond strength of orthodontic brackets and the association of methodological variables on the influence of bond strength outcome. In vitro studies were selected to answer whether adhesive resin application increases the immediate shear bond strength of metal orthodontic brackets bonded with a photo-cured orthodontic adhesive. Studies included were those comparing a group having adhesive resin to a group without adhesive resin with the primary outcome measurement shear bond strength in MPa. A systematic electronic search was performed in PubMed and Scopus databases. Nine studies were included in the analysis. Based on the pooled data and due to a high heterogeneity among studies (I(2)  =  93.3), a meta-regression analysis was conducted. The analysis demonstrated that five experimental conditions explained 86.1% of heterogeneity and four of them had significantly affected in vitro shear bond testing. The shear bond strength of metal brackets was not significantly affected when bonded with adhesive resin, when compared to those without adhesive resin. The adhesive resin application can be set aside during metal bracket bonding to enamel regardless of the type of orthodontic adhesive used.

The assessment of bond strength between heat damaged concrete and high strength fibre reinforced concrete

NASA Astrophysics Data System (ADS)

Zahid, M. Z. A. Mohd; Muhamad, K.

2017-09-01

The aim of this study is to assess the bond strength between heat damaged concrete and high strength fibre reinforced concrete (HPFRC). Firstly, this paper presents the various steps taken to prepare the HPFRC with self-compacting property. The minimum targeted slump flow is 600 mm and minimum targeted compressive strength is 80 MPa. The key mix variables considered are such as type of superplasticizer, water cement ratio and silica fume content. Then, the bond strength between the heat damaged concrete with HPFRC was examined. The experimental parameters are heating temperature, surface treatment technique and curing method and the results show that, all experimental parameters are significantly affected the bond strength between heat damaged concrete and HPFRC.

Evaluation of the Shear Bond Strength of Composite Resin to Wet and Dry Enamel Using Dentin Bonding Agents Containing Various Solvents.

PubMed

Usha, Carounanidy; Ramarao, Sathyanarayanan; John, Bindu Meera; Rajesh, Praveen; Swatha, S

2017-01-01

Bonding of composite resin to dentin mandates a wet substrate whereas, enamel should be dry. This may not be easily achievable in intracoronal preparations where enamel and dentin are closely placed to each other. Therefore, Dentin Bonding Agents (DBA) are recommended for enamel and dentinal bonding, where enamel is also left moist. A research question was raised if the "enamel-only" preparations will also benefit from wet enamel bonding and contemporary DBA. The aim of this study was to compare the shear bond strengths of composite resin, bonded to dry and wet enamel using fifth generation DBA (etch and rinse system) containing various solvents such as ethanol/water, acetone and ethanol. The crowns of 120 maxillary premolars were split into buccal and lingual halves. They were randomly allocated into four groups of DBA: Group 1-water/ethanol based, Group 2-acetone based, Group 3-ethanol based, Group 4-universal bonding agent (control group). The buccal halves and lingual halves were bonded using the wet bonding and dry bonding technique respectively. After application of the DBAs and composite resin build up, shear bond strength testing was done. Group 1 (ethanol/water based ESPE 3M, Adper Single Bond) showed highest bond strength of (23.15 MPa) in dry enamel. Group 2 (acetone based Denstply, Prime and Bond NT, showed equal bond strength in wet and dry enamel condition (18.87 MPa and 18.02 MPa respectively). Dry enamel bonding and ethanol/water based etch and rinse DBA can be recommended for "enamel-only" tooth preparations.

Indirect resin composite restorations bonded to dentin using self-adhesive resin cements applied with an electric current-assisted method.

PubMed

Gotti, Valeria Bisinoto; Feitosa, Victor Pinheiro; Sauro, Salvatore; Correr-Sobrinho, Lourenço; Correr, Americo Bortolazzo

2014-10-01

To evaluate the effects of an electric current-assisted application on the bond strength and interfacial morphology of self-adhesive resin cements bonded to dentin. Indirect resin composite build-ups were luted to prepared dentin surfaces using two self-adhesive resin cements (RelyX Unicem and BisCem) and an ElectroBond device under 0, 20, or 40 μA electrical current. All specimens were submitted to microtensile bond strength test and to interfacial SEM analysis. The electric current-assisted application induced no change (P > 0.05) on the overall bond strength, although RelyX Unicem showed significantly higher bond strength (P < 0.05) than BisCem. Similarly, no differences were observed in terms of interfacial integrity when using the electrical current applicator.

Novel fabrication method for zirconia restorations: bonding strength of machinable ceramic to zirconia with resin cements.

PubMed

Kuriyama, Soichi; Terui, Yuichi; Higuchi, Daisuke; Goto, Daisuke; Hotta, Yasuhiro; Manabe, Atsufumi; Miyazaki, Takashi

2011-01-01

A novel method was developed to fabricate all-ceramic restorations which comprised CAD/CAM-fabricated machinable ceramic bonded to CAD/CAM-fabricated zirconia framework using resin cement. The feasibility of this fabrication method was assessed in this study by investigating the bonding strength of a machinable ceramic to zirconia. A machinable ceramic was bonded to a zirconia plate using three kinds of resin cements: ResiCem (RE), Panavia (PA), and Multilink (ML). Conventional porcelain-fused-to-zirconia specimens were also prepared to serve as control. Shear bond strength test (SBT) and Schwickerath crack initiation test (SCT) were carried out. SBT revealed that PA (40.42 MPa) yielded a significantly higher bonding strength than RE (28.01 MPa) and ML (18.89 MPa). SCT revealed that the bonding strengths of test groups using resin cement were significantly higher than those of Control. Notably, the bonding strengths of RE and ML were above 25 MPa even after 10,000 times of thermal cycling -adequately meeting the ISO 9693 standard for metal-ceramic restorations. These results affirmed the feasibility of the novel fabrication method, in that a CAD/CAM-fabricated machinable ceramic is bonded to a CAD/CAM-fabricated zirconia framework using a resin cement.

A study on the compatibility between one-bottle dentin adhesives and composite resins using micro-shear bond strength.

PubMed

Song, Minju; Shin, Yooseok; Park, Jeong-Won; Roh, Byoung-Duck

2015-02-01

This study was performed to determine whether the combined use of one-bottle self-etch adhesives and composite resins from same manufacturers have better bond strengths than combinations of adhesive and resins from different manufacturers. 25 experimental micro-shear bond test groups were made from combinations of five dentin adhesives and five composite resins with extracted human molars stored in saline for 24 hr. Testing was performed using the wire-loop method and a universal testing machine. Bond strength data was statistically analyzed using two way analysis of variance (ANOVA) and Tukey's post hoc test. Two way ANOVA revealed significant differences for the factors of dentin adhesives and composite resins, and significant interaction effect (p < 0.001). All combinations with Xeno V (Dentsply De Trey) and Clearfil S(3) Bond (Kuraray Dental) adhesives showed no significant differences in micro-shear bond strength, but other adhesives showed significant differences depending on the composite resin (p < 0.05). Contrary to the other adhesives, Xeno V and BondForce (Tokuyama Dental) had higher bond strengths with the same manufacturer's composite resin than other manufacturer's composite resin. Not all combinations of adhesive and composite resin by same manufacturers failed to show significantly higher bond strengths than mixed manufacturer combinations.

[Comparative study of bond strength between zirconia ceramics and 4 luting cements].

PubMed

Zheng, Hu; Zhang, Xian-Fang; Han, Dong-Wei

2007-02-01

To study the bonding strength of zirconia ceramics with 4 kinds of luting cement materials. Blocks of sintered zirconia ceramics were cut and randomly divided into 4 groups with 16 slices in each group. They were treated with sandblasting and bonded with 4 kinds of luting cements respectively. After preserved in 37 degrees C distilled-water for 24 hours and 30 days, the shear bonding strength of these specimens was tested and the data were analyzed by SAS6.12 software package and bond section were observed by scanning electron microscope. Two-way ANOVA revealed that the group of PanaviaF could attain the highest shear bonding strength: (34.7+/-3.44) MPa (after 24 hours), (31.5+/-3.44) MPa (after 1 month), which was significantly different from other treatment methods (P<0.01). The initial shear bonding strength of the groups of resin-reinforced glass ionomer was (15.5+/-2.71) MPa, (16.0+/-1.77) MPa (after 24 hours) but dropped markedly to (6.80+/-1.24) MPa, (3.38+/-2.32) MPa after 30 days (P<0.05). Resin luting cement containing phosphate monomer (MDP) can provide zirconia ceramics a strong and long-lasting bonding. Resin-reinforced glass ionomer can get good bonding strength too, but can't last long.

Effect of digluconate chlorhexidine on bond strength between dental adhesive systems and dentin: A systematic review.

PubMed

Dionysopoulos, Dimitrios

2016-01-01

This study aimed to systematically review the literature for the effect of digluconate chlorhexidine (CHX) on bond strength between dental adhesive systems and dentin of composite restorations. The electronic databases that were searched to identify manuscripts for inclusion were Medline via PubMed and Google search engine. The search strategies were computer search of the database and review of reference lists of the related articles. Search words/terms were as follows: (digluconate chlorhexidine*) AND (dentin* OR adhesive system* OR bond strength*). Bond strength reduction after CHX treatments varied among the studies, ranging 0-84.9%. In most of the studies, pretreatment CHX exhibited lower bond strength reduction than the control experimental groups. Researchers who previously investigated the effect of CHX on the bond strength of dental adhesive systems on dentin have reported contrary results, which may be attributed to different experimental methods, different designs of the experiments, and different materials investigated. Further investigations, in particular clinical studies, would be necessary to clarify the effect of CHX on the longevity of dentin bonds.

Effect of denture cleansing agents on tensile and shear bond strengths of soft liners to acrylic denture base.

PubMed

Mahboub, Farhang; Salehsaber, Fariba; Parnia, Fereydoon; Gharekhani, Vahedeh; Kananizadeh, Yousef; Taghizadeh, Mahsa

2017-01-01

Background. The aim of the present study was to evaluate the effect of Corega and 2.5% sodium hypochlorite cleansing agents on the shear and tensile bond strengths of GC soft liner to denture base. Methods. A total of 144 samples (72 samples for tensile and 72 for shear bond strength evaluations) were prepared. The samples in each group were subdivided into three subgroups in terms of the cleansing agent used (2.5% sodium hypochlorite, Corega and distilled water [control group]). All the samples were stored in distilled water, during which each sample was immersed for 15 minutes daily in sodium hypochlorite or Corega solutions. After 20 days the tensile and shear bond strengths were determined using a universal testing machine. In addition, a stereomicroscope was used to evaluate fracture modes. Data were analyzed with one-way ANOVA, using SPSS 16. Results. The results of post hoc Tukey tests showed significant differences in the mean tensile and shear bond strength values between the sodium hypochlorite group with Corega and control groups (P=0.001 for comparison of tensile bond strengths between the sodium hypochlorite and control groups, and P<0.001 for the comparison of tensile bond strengths between the sodium hypochlorite and Corega groups and the shear bond strengths between the sodium hypochlorite and Corega groups, and sodium hypochlorite and control groups).The majority of failures were cohesive in the control and Corega groups and cohesive/adhesive in the sodium hypochlorite group. Conclusion. Immersion of soft liners in Corega will result in longevity of soft liners compared to immersion in sodium hypochlorite solution and sodium hypochlorite solution significantly decreased the tensile and shear bond strengths compared to the control and Corega groups.

Effect of denture cleansing agents on tensile and shear bond strengths of soft liners to acrylic denture base

PubMed Central

Mahboub, Farhang; Salehsaber, Fariba; Parnia, Fereydoon; Gharekhani, Vahedeh; Kananizadeh, Yousef; Taghizadeh, Mahsa

2017-01-01

Background. The aim of the present study was to evaluate the effect of Corega and 2.5% sodium hypochlorite cleansing agents on the shear and tensile bond strengths of GC soft liner to denture base. Methods. A total of 144 samples (72 samples for tensile and 72 for shear bond strength evaluations) were prepared. The samples in each group were subdivided into three subgroups in terms of the cleansing agent used (2.5% sodium hypochlorite, Corega and distilled water [control group]). All the samples were stored in distilled water, during which each sample was immersed for 15 minutes daily in sodium hypochlorite or Corega solutions. After 20 days the tensile and shear bond strengths were determined using a universal testing machine. In addition, a stereomicroscope was used to evaluate fracture modes. Data were analyzed with one-way ANOVA, using SPSS 16. Results. The results of post hoc Tukey tests showed significant differences in the mean tensile and shear bond strength values between the sodium hypochlorite group with Corega and control groups (P=0.001 for comparison of tensile bond strengths between the sodium hypochlorite and control groups, and P<0.001 for the comparison of tensile bond strengths between the sodium hypochlorite and Corega groups and the shear bond strengths between the sodium hypochlorite and Corega groups, and sodium hypochlorite and control groups).The majority of failures were cohesive in the control and Corega groups and cohesive/adhesive in the sodium hypochlorite group. Conclusion. Immersion of soft liners in Corega will result in longevity of soft liners compared to immersion in sodium hypochlorite solution and sodium hypochlorite solution significantly decreased the tensile and shear bond strengths compared to the control and Corega groups. PMID:29184635

Effect of an Extra Hydrophobic Resin Layer on Repair Shear Bond Strength of a Silorane-Based Composite Resin

PubMed Central

Mohammadi, Narmin; Bahari, Mahmoud; Kimyai, Soodabeh; Rahbani Nobar, Behnam

2015-01-01

Objectives: Composite repair is a minimally invasive and conservative approach. This study aimed to evaluate the effect of an additional hydrophobic resin layer on the repair shear bond strength of a silorane-based composite repaired with silorane or methacrylate-based composite. Materials and Methods: Sixty bar-shaped composite blocks were fabricated and stored in saline for 72 hours. The surface of the samples were roughened by diamond burs and etched with phosphoric acid; then, they were randomly divided into three groups according to the repairing process: Group 1: Silorane composite-silorane bonding agent-silorane composite; group 2: Silorane composite-silorane bonding agent-hydrophobic resin-silorane composite, and group 3: Silorane composite-silorane bonding agent-hydrophobic resin methacrylate-based composite. Repairing composite blocks measured 2.5×2.5×5mm. After repairing, the samples were stored in saline for 24 hours and thermocycled for 1500 cycles. The repair bond strength was measured at a strain rate of 1mm/min. Twenty additional cylindrical composite blocks (diameter: 2.5mm, height: 6mm) were also fabricated for measuring the cohesive strength of silorane-based composite. The data were analyzed using One-way ANOVA and the post hoc Tukey’s test (α=0.05). Results: Cohesive bond strength of silorane composite was significantly higher than the repair bond strengths in other groups (P<0.001). The repair bond strength of group 3 was significantly higher than that of group 1 (P=0.001). Conclusion: Application of an additional hydrophobic resin layer for repair of silorane-based composite with a methacrylate-based composite enhanced the repair shear bond strength. PMID:27559348

Effects of drying agents on bond strength of etch-and-rinse adhesive systems to enamel immediately after bleaching.

PubMed

Niat, Alireza Boruzi; Yazdi, Fatmeh Maleknejad; Koohestanian, Niloufar

2012-12-01

To determine the effect of drying agents and adhesive solvents on the bond strength of resin composite to enamel immediately after bleaching. Sixty healthy human premolars were bleached using 15% carbamide peroxide gel and randomly divided into three groups according to the immersing solutions applied immediately after bleaching: 70% alcohol, acetone, and distilled water. Each group was randomly divided into two subgroups according to the adhesives that were applied: an alcohol-based adhesive (Single Bond) and an acetone-based adhesive (One Step). By using rubber washers, composite Z100 was placed onto the enamel and shear bond strength was evaluated in a universal testing machine at a crosshead speed of 1 mm/min. The type of failure was also assessed using a stereomicroscope. The data were statistically analyzed by two-way ANOVA and Tukey's post-hoc test (α = 0.05). Fisher's Exact test was used to evaluate differences in the failure modes. Statistical analysis showed that the bond strength of the distilled water groups was significantly lower than that of the other groups, but the bond strengths of the two groups where a drying agent was applied were similar to that of the unbleached group. The acetone-based adhesive (One Step) provided higher bond strength than did the alcohol-based adhesive (Single Bond) (p < 0.05). There was no interaction between the two variables (p > 0.05). Fisher's Exact test showed there was no significant difference in the failure mode of all the experimental groups (p > 0.05). The application of drying agents improves the bond strength of resin composite to bleached enamel. Furthermore, the acetone-based adhesive used in the study had a higher bond strength to bleached enamel than did the alcohol-based adhesive used.

Initial Screening of Environmentally Sustainable Surface Pretreatments for Adhesive Bonding Applications

DTIC Science & Technology

2017-05-17

490F Type IV inorganic pretreatments resulted in little to no loss of adhesive bond strength during H/W conditioning and their potential use as bonding...sustainable TT-C-490F pretreatments resulted in little to no loss of adhesive bond strength during H/W conditioning and their potential use as...pretreatment was applied. Environmentally sustainable TT-C-490F Type IV inorganic pretreatments resulted in little to no loss of adhesive bond strength during

Degradation of Multimode Adhesive System Bond Strength to Artificial Caries-Affected Dentin Due to Water Storage.

PubMed

Follak, A C; Miotti, L L; Lenzi, T L; Rocha, R O; Soares, F Z

The purpose of this study was to evaluate the influence of water storage on bond strength of multimode adhesive systems to artificially induced caries-affected dentin. One hundred twelve sound bovine incisors were randomly assigned to 16 groups (n=7) according to the dentin condition (sound; SND, artificially induced caries-affected dentin; CAD, cariogenic challenge by pH cycling for 14 days); the adhesive system (SU, Scotchbond Universal Adhesive; AB, All-Bond Universal; PB, Prime & Bond Elect; SB, Adper Single Bond 2; and CS, Clearfil SE Bond), and the etching strategy (etch-and-rinse and self-etch). All adhesive systems were applied under manufacturer's instructions to flat dentin surfaces, and a composite block was built up on each dentin surface. After 24 hours of water storage, the specimens were sectioned into stick-shaped specimens (0.8 mm 2 ) and submitted to a microtensile test immediately (24 hours) or after six months of water storage. Bond strength data (MPa) were analyzed using three-way repeated-measures analysis of variance and post hoc Tukey test (α=5%), considering each substrate separately (SND and CAD). The etching strategy did not influence the bond strength of multimode adhesives, irrespective of the dentin condition. Water storage only reduced significantly the bond strength to CAD. The degradation of bond strength due to water storage was more pronounced in CAD, regardless of the etching strategy.

Effect of saliva contamination and cleansing solutions on the bond strengths of self-etch adhesives to dentin.

PubMed

Sheikh, Huma; Heymann, Harald O; Swift, Edward J; Ziemiecki, Thomas L; Ritter, André V

2010-12-01

This study determined the effect of saliva contamination and cleansing solutions on microtensile bond strengths of self-etch adhesives to dentin. Seventy-five human molars were ground flat to expose mid-coronal dentin and randomly assigned to five groups (N = 15): no contamination, saliva contamination without cleansing, saliva and cleansing with water, saliva and cleansing with 2% chlorhexidine, and saliva and cleansing with 5% sodium hypochlorite. One-third of the specimens in each group of 15 were bonded with Adper Prompt L-Pop (all-in-one self-etch adhesive; 3M ESPE, St. Paul, MN, USA), one-third with Adper Easy Bond (all-in-one self-etch adhesive; 3M ESPE), and one-third with Clearfil SE Bond (self-etch primer system; Kuraray America, New York, NY, USA). Specimens were restored with composite and processed for microtensile bond strength testing (5-6 rods/tooth). Mean bond strengths ranged from 17.3 MPa for Adper Prompt L-Pop after water cleansing to 69.3 MPa for Clearfil SE Bond after water cleansing. For all three adhesives, there was no statistically significant difference in bond strengths between the saliva contaminated group, the cleansing groups, and the no contamination groups. Neither saliva nor the cleansing solutions adversely affected bond strengths of the self-etch adhesive systems. © 2010, COPYRIGHT THE AUTHORS. JOURNAL COMPILATION © 2010, WILEY PERIODICALS, INC.

Effect of surface treatment methods on the shear bond strength of auto-polymerized resin to thermoplastic denture base polymer.

PubMed

Koodaryan, Roodabeh; Hafezeqoran, Ali

2016-12-01

Polyamide polymers do not provide sufficient bond strength to auto-polymerized resins for repairing fractured denture or replacing dislodged denture teeth. Limited treatment methods have been developed to improve the bond strength between auto-polymerized reline resins and polyamide denture base materials. The objective of the present study was to evaluate the effect of surface modification by acetic acid on surface characteristics and bond strength of reline resin to polyamide denture base. 84 polyamide specimens were divided into three surface treatment groups (n=28): control (N), silica-coated (S), and acid-treated (A). Two different auto-polymerized reline resins GC and Triplex resins were bonded to the samples (subgroups T and G, respectively, n=14). The specimens were subjected to shear bond strength test after they were stored in distilled water for 1 week and thermo-cycled for 5000 cycles. Data were analyzed with independent t-test, two-way analysis of variance (ANOVA), and Tukey's post hoc multiple comparison test (α=.05). The bond strength values of A and S were significantly higher than those of N ( P <.001 for both). However, statistically significant difference was not observed between group A and group S. According to the independent Student's t-test, the shear bond strength values of AT were significantly higher than those of AG ( P <.001). The surface treatment of polyamide denture base materials with acetic acid may be an efficient and cost-effective method for increasing the shear bond strength to auto-polymerized reline resin.

Effects of blood contamination on resin-resin bond strength.

PubMed

Eiriksson, Sigurdur O; Pereira, Patricia N R; Swift, Edward J; Heymann, Harald O; Sigurdsson, Asgeir

2004-02-01

Incremental placement and curing of resin composites has been recommended. However, this requires longer operating time, and therefore, increased risk of contamination. The purpose of this study was to evaluate the effects of blood contamination on microtensile bond strengths (microTBS) between resin interfaces and to determine the best decontamination method to re-establish the original resin-resin bond strength. The top surfaces of 64, 4-mm composite blocks (Z-250, Renew, APX, Pertac II) were untreated as the control, or were treated as follows: blood applied and dried on the surface (Treatment 1), blood applied, rinsed, dried (Treatment 2), blood applied, rinsed, and an adhesive applied (Single Bond, One-Step, Clearfil SE, Prompt L-Pop) (Treatment 3). Fresh composite was applied and light-cured in 2-mm increments. After 24 h storage in water, the specimens were sectioned into 0.7-mm thick slabs, trimmed to a cross-sectional area of 1 mm(2), and loaded to failure at a crosshead speed of 1 mm/min using an Instron universal testing machine. Data were analyzed using two-way ANOVA and Fisher's PLSD test (p<0.05). Control values ranged from 45.1 MPa for Pertac II to 71.5 MPa for APX. Untreated blood contamination resulted in resin-resin bond strengths of only 1.0-13.1 MPa. Rinsing raised bond strengths to over 40 MPa for each material. Use of an adhesive further increased bond strengths except for Pertac II. Rinsing blood from contaminated surfaces increases the resin-resin bond strength significantly and the application of an appropriate adhesive increases the bond strength to control levels.

Push-out bond strengths of fiber-reinforced composite posts with various resin cements according to the root level

PubMed Central

Chang, Hoon-Sang; Noh, Young-Sin; Lee, Yoon; Min, Kyung-San

2013-01-01

PURPOSE The aim of this study was to determine whether the push-out bond strengths between the radicular dentin and fiber reinforced-composite (FRC) posts with various resin cements decreased or not, according to the coronal, middle or apical level of the root. MATERIALS AND METHODS FRC posts were cemented with one of five resin cement groups (RelyX Unicem: Uni, Contax with activator & LuxaCore-Dual: LuA, Contax & LuxaCore-Dual: Lu, Panavia F 2.0: PA, Super-Bond C&B: SB) into extracted human mandibular premolars. The roots were sliced into discs at the coronal, middle and apical levels. Push-out bond strength tests were performed with a universal testing machine at a crosshead speed of 0.5 mm/min, and the failure aspect was analyzed. RESULTS There were no significant differences (P>.05) in the bond strengths of the different resin cements at the coronal level, but there were significant differences in the bond strengths at the middle and apical levels (P<.05). Only the Uni and LuA cements did not show any significant decrease in their bond strengths at all the root levels (P>.05); all other groups had a significant decrease in bond strength at the middle or apical level (P<.05). The failure aspect was dominantly cohesive at the coronal level of all resin cements (P<.05), whereas it was dominantly adhesive at the apical level. CONCLUSION All resin cement groups showed decreases in bond strengths at the middle or apical level except LuA and Uni. PMID:24049569

Shear bond strength of resin composite bonded with two adhesives: Influence of Er: YAG laser irradiation distance

PubMed Central

Shirani, Farzaneh; Birang, Reza; Malekipour, Mohammad Reza; Hourmehr, Zahra; Kazemi, Shantia

2014-01-01

Background: Dental surfaces prepared with different Er:YAG laser distance may have different characteristics compared with those prepared with conventional instruments. The aim of this study was to investigate the effect of Er:YAG laser irradiation distance from enamel and dentin surfaces on the shear bond strength of composite with self-etch and etch and rinse bonding systems compared with conventional preparation method. Materials and Methods: Two hundred caries-free human third molars were randomly divided into twenty groups (n = 10). Ten groups were designated for enamel surface (E1-E10) and ten for dentin surface (D1-D10). Er: YAG laser (2940 nm) was used on the E1-E8 (240 mJ, 25 Hz) and D1-D8 (140 mJ, 30 Hz) groups at four different distances of 0.5 (standard), 2, 4 and 11 mm. Control groups (E9, E10, D9 and D10) were ground with medium grit diamond bur. The enamel and dentin specimens were divided into two subgroups that were bonded with either Single Bond or Clearfil SE Bond. Resin composite (Z100) was dispensed on prepared dentin and enamel. The shear bond strengths were tested using a universal testing machine. Data were analyzed by SPSS12 statistical software using three way analysis of variance, Tukey and independent t-test. P < 0.05 was considered as significant. Results: There was a significant difference between enamel and dentin substrates (P < 0.001) and between lased and un-lased groups; the un-lased group had significantly higher bond strength (P < 0.001). Shear bond strength increased significantly with an increase in the laser irradiation distance (P < 0.05) on enamel surfaces (in both bonding agent subgroups) and on dentin surfaces (in the Single Bond subgroup). Conclusion: Laser irradiation decreases shear bond strength. Irradiation distance affects shear bond strength and increasing the distance would decrease the negative effects of laser irradiation. PMID:25540665

UV irradiation improves the bond strength of resin cement to fiber posts.

PubMed

Zhong, Bo; Zhang, Yong; Zhou, Jianfeng; Chen, Li; Li, Deli; Tan, Jianguo

2011-01-01

The purpose is to evaluate the effect of UV irradiation on the bond strength between epoxy-based glass fiber posts and resin cement. Twelve epoxy-based glass fiber posts were randomly divided into three groups. Group 1 (Cont.): No surface treatment. Group 2 (Low-UV): UV irradiation was conducted from a distance of 10 cm for 10 min. Group 3 (High-UV): UV irradiation was conducted from a distance of 1 cm for 3 min. A resin cement (CLEARFIL SA LUTING) was used for the post cementation to form resin slabs which contained fiber posts in the center. Microtensile bond strengths were tested and the mean bond strengths (MPa) were 18.81 for Cont. group, 23.65 for Low-UV group, 34.75 for High-UV group. UV irradiation had a significant effect on the bond strength (p<0.05). UV irradiation demonstrates its capability to improve the bond strength between epoxy-based glass fiber posts and resin cement.

Effect of ultraviolet light irradiation period on bond strengths between fiber-reinforced composite post and core build-up composite resin.

PubMed

Asakawa, Yuya; Takahashi, Hidekazu; Iwasaki, Naohiko; Kobayashi, Masahiro

2014-01-01

The aim of the present study was to characterize the effects of the ultraviolet light (UV) irradiation period on the bond strength of fiber-reinforced composite (FRC) posts to core build-up resin. Three types of FRC posts were prepared using polymethyl methacrylate, urethane dimethacrylate, and epoxy resin. The surfaces of these posts were treated using UV irradiation at a distance of 15 mm for 0 to 600 s. The pull-out bond strength was measured and analyzed with the Dunnett's comparison test (α=0.05). The bond strengths of the post surfaces without irradiation were 6.9 to 7.4 MPa; those after irradiation were 4.2 to 26.1 MPa. The bond strengths significantly increased after 15 to 120-s irradiation. UV irradiation on the FRC posts improved the bond strengths between the FRC posts and core build-up resin regardless of the type of matrix resin.

Role of oxygen on the optical properties of borate glass doped with ZnO

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abdel-Baki, Manal; El-Diasty, Fouad, E-mail: fdiasty@yahoo.com

2011-10-15

Lithium tungsten borate glass (0.56-x)B{sub 2}O{sub 3}-0.4Li{sub 2}O-xZnO-0.04WO{sub 3} (0{<=}x{<=}0.1 mol%) is prepared by the melt quenching technique for photonic applications. Small relative values of ZnO are used to improve the glass optical dispersion and to probe as well the role of oxygen electronic polarizability on its optical characteristics. The spectroscopic properties of the glass are determined in a wide spectrum range (200-2500 nm) using a Fresnel-based spectrophotometric technique. Based on the Lorentz-Lorenz theory, as ZnO content increases on the expense of B{sub 2}O{sub 3} the glass molar polarizability increased due to an enhanced unshared oxide ion 2p electron density,more » which increases ionicity of the chemical bonds of glass. The role of oxide ion polarizability is explained in accordance with advanced measures and theories such as optical basicity, O 1s binding energy, the outer most cation binding energy in Yamashita-Kurosawa's interionic interaction parameter and Sun's average single bond strength. FT-IR measurements confirm an increase in bridging oxygen bonds, as a result of replacement of ZnO by B{sub 2}O{sub 3}, which increase the UV glass transmission window and transmittance. - Graphical abstract: O1s, Yamashita-Kurosawa's parameter and average single bond strength of charge overlapping between electronic shells are used to explain enhanced oxide ion 2p electron density, which increases refractive index of glasses. Highlights: > New borate glass for photonic application is prepared. > The dispersion property of the glass is effectively controlled using small amounts of ZnO. > ZnO is used to probe the glass structure and investigate the role of oxygen on the obtained optical properties of the glasses. > Modern theories are used to explain enhanced unshared oxide ion 2p electron density, which increases ionicity of chemical bonds of the glass.« less

The effect of air thinning on dentin adhesive bond strength.

PubMed

Hilton, T J; Schwartz, R S

1995-01-01

The purpose of this study was to determine if air thinning three dentin adhesives would affect bond strength to dentin. Ninety human molars were mounted in acrylic and the occlusal surfaces ground to expose a flat dentin surface. Thirty teeth were randomly assigned to one of the following dentin bonding agent/composite combinations: A) Universal Bond 3/TPH (Caulk), B) All-Bond 2/Bis-Fil-P (Bisco), and C) Scotchbond Multi-Purpose/Z-100 (3m). The primers were applied following the manufacturers' instructions. The adhesives were applied by two methods. A thin layer of adhesive was applied with a brush to 15 specimens in each group and light cured. Adhesive was brushed on to the remaining 15 teeth in the group, air thinned for 3 seconds, and then polymerized. The appropriate composite was applied in 2 mm increments and light cured utilizing a 5 mm-in-diameter split Teflon mold. Following 3 months of water storage, all groups were shear tested to failure on an Instron Universal Testing Machine. Bond strength was significantly higher in all groups when the dentin bonding agent was painted on without being air thinned. Scotchbond Multi-Purpose had significantly higher bond strength than All-Bond 2, which had significantly higher bond strength than Universal Bond 3.

Evaluation of shear bond strength of porcelain bonded to laser welded titanium surface and determination of mode of bond failure.

PubMed

Patil, Narendra P; Dandekar, Minal; Nadiger, Ramesh K; Guttal, Satyabodh S

2010-09-01

The aim of this study was to evaluate the shear bond strength of porcelain to laser welded titanium surface and to determine the mode of bond failure through scanning electron microscopy (SEM) and energy dispersive spectrophotometry (EDS). Forty five cast rectangular titanium specimens with the dimension of 10 mm x 8 mm x 1 mm were tested. Thirty specimens had a perforation of 2 mm diameter in the centre. These were randomly divided into Group A and B. The perforations in the Group B specimens were repaired by laser welding using Cp Grade II titanium wire. The remaining 15 specimens were taken as control group. All the test specimens were layered with low fusing porcelain and tested for shear bond strength. The debonded specimens were subjected to SEM and EDS. Data were analysed with 1-way analysis of variance and Student's t-test for comparison among the different groups. One-way analysis of variance (ANOVA) showed no statistically significant difference in shear bond strength values at a 5% level of confidence. The mean shear bond strength values for control group, Group A and B was 8.4 +/- 0.5 Mpa, 8.1 +/- 0.4 Mpa and 8.3 +/- 0.3 Mpa respectively. SEM/EDS analysis of the specimens showed mixed and cohesive type of bond failure. Within the limitations of the study laser welding did not have any effect on the shear bond strength of porcelain bonded to titanium.

Tensile bond strength of metal bracket bonding to glazed ceramic surfaces with different surface conditionings.

PubMed

Akhoundi, Ms Ahmad; Kamel, M Rahmati; Hashemi, Sh Mahmood; Imani, M

2011-01-01

The objective of this study was to compare the tensile bond strength of metal brackets bonding to glazed ceramic surfaces using three various surface treatments. Forty two glazed ceramic disks were assigned to three groups. In the first and second groups the specimens were etched with 9.5% hydrofluoric acid (HFA). Subsequently in first group, ceramic primer and adhesive were applied, but in second group a bonding agent alone was used. In third group, specimens were treated with 35% phosphoric acid followed by ceramic primer and adhesive application. Brackets were bonded with light cure composites. The specimens were stored in distilled water in the room temperature for 24 hours and thermocycled 500 times between 5°C and 55°C. The universal testing machine was used to test the tensile bond strength and the adhesive remenant index scores between three groups was evaluated. The data were subjected to one-way ANOVA, Tukey and Kruskal-Wallis tests respectively. The tensile bond strength was 3.69±0.52 MPa forfirst group, 2.69±0.91 MPa for second group and 3.60±0.41 MPa for third group. Group II specimens showed tensile strength values significantly different from other groups (P<0.01). In spite of limitations in laboratory studies it may be concluded that in application of Scotch bond multipurpose plus adhesive, phosphoric acid can be used instead of HFA for bonding brackets to the glazed ceramic restorations with enough tensile bond strength.

Effects of Chemical Cross-linkers on Caries-affected Dentin Bonding

PubMed Central

Macedo, G.V.; Yamauchi, M.; Bedran-Russo, A.K.

2009-01-01

The achievement of a strong and stable bond between composite resin and dentin remains a challenge in restorative dentistry. Over the past two decades, dental materials have been substantially improved, with better handling and bonding characteristics. However, little attention has been paid to the contribution of collagen structure/stability to bond strength. We hypothesized that the induction of cross-linking in dentin collagen improves dentin collagen stability and bond strength. This study investigated the effects of glutaraldehyde- and grape seed extract-induced cross-linking on the dentin bond strengths of sound and caries-affected dentin, and on the stability of dentin collagen. Our results demonstrated that the application of chemical cross-linking agents to etched dentin prior to bonding procedures significantly enhanced the dentin bond strengths of caries-affected and sound dentin. Glutaraldehyde and grape seed extract significantly increased dentin collagen stability in sound and caries-affected dentin, likely via distinct mechanisms. PMID:19892915

Bonding strength of alkyl-2-cyanoacrylates to bone in vitro.

PubMed

Kilpikari, J; Lapinsuo, M; Törmälä, P; Pätiälä, H; Rokkanen, P

1986-10-01

This study measured the bonding strength between alkyl-2-cyanoacrylates and bone, and examined how treatment of the bone surface with acid, and prolonged exposure to moisture, affected this strength. The initial strength of all cyanoacrylates was high (9.6-11.2 N/mm2). In long-term experiments under water, n- and i-butylcyanoacrylates lost their strength at a far slower rate than ethylcyanoacrylates. However, the butylcyanoacrylates also showed a decrease of 15% in strength after three weeks. Pretreatment of the bone surface with acid did not have a marked effect on bonding strength, although SEM investigation revealed that the acid treatment had increased the porosity of the bone surface. A study of the fracture surface proved that the adhesive film tended to loosen or break after 3 to 6 weeks under water. The decrease in the bonding strength was probably due to the degradation of the adhesive film in water which loosened mechanical bonds between the bone and adhesive. Considering clinical use it would be necessary to achieve better long-term strength.

Room temperature bonding and debonding of polyimide film and glass substrate based on surface activate bonding method

NASA Astrophysics Data System (ADS)

Takeuchi, Kai; Fujino, Masahisa; Matsumoto, Yoshiie; Suga, Tadatomo

2018-02-01

The temporary bonding of polyimide (PI) films and glass substrates is a key technology for realizing flexible devices with thin-film transistors (TFTs). In this paper, we report the surface activated bonding (SAB) method using Si intermediate layers and its bonding and debonding mechanisms after heating. The bonding interface composed of Si and Fe shows a higher bond strength than the interface of only Si, while the bond strengths of both interfaces decrease with post bonding heating. It is also clarified by composition analysis on the debonded surfaces and cross-sectional observation of the bonding interface that the bond strength depends on the toughness of the intermediated layers and PI. The SAB method using Si intermediate layers is found to be applicable to the bonding and debonding of PI and glass.

Effect of surface treatment on bond strength between an indirect composite material and a zirconia framework.

PubMed

Komine, Futoshi; Fushiki, Ryosuke; Koizuka, Mai; Taguchi, Kohei; Kamio, Shingo; Matsumura, Hideo

2012-03-01

The present study evaluated the effect of various surface treatments for zirconia ceramics on shear bond strength between an indirect composite material and zirconia ceramics. In addition, we investigated the durability of shear bond strength by using artificial aging (20,000 thermocycles). A total of 176 Katana zirconia disks were randomly divided into eight groups according to surface treatment, as follows: group CON (as-milled); group GRD (wet-ground with 600-grit silicon carbide abrasive paper); groups 0.05, 0.1, 0.2, 0.4, and 0.6 MPa (airborne-particle abrasion at 0.05, 0.1, 0.2, 0.4, and 0.6 MPa, respectively); and group HF (9.5% hydrofluoric acid etching). Shear bond strength was measured at 0 thermocycles in half the specimens after 24-h immersion. The remaining specimens were subjected to 20,000 thermocycles before shear bond strength testing. Among the eight groups, the 0.1, 0.2, 0.4, and 0.6 MPa airborne-particle abraded groups had significantly higher bond strengths before and after thermocycling. The Mann-Whitney U-test revealed no significant difference in shear bond strength between 0 and 20,000 thermocycles, except in the 0.2 MPa group (P = 0.013). From the results of this study, use of airborne-particle abrasion at a pressure of 0.1 MPa or higher increases initial and durable bond strength between an indirect composite material and zirconia ceramics.

Evaluation of the effect of three innovative recyling methods on the shear bond strength of stainless steel brackets-an in vitro study.

PubMed

Gupta, Neeraj; Kumar, Dilip; Palla, Aparna

2017-04-01

Orthodontists are commonly faced with the decision of what to do with debonded or inaccurately positioned brackets. An economical option to this dilemma is to recycle the brackets. Many recycling methods have been proposed, but the optimal bond strength of these recycled brackets needs further evaluation. Objectives: To evaluate and compare the effect of three recycling methods: (i) Sandblasting (ii) Sandblasting / direct flaming (iii) Sandblasting /direct flaming /acid bath solution on shear bond strength (SBS) of stainless steel brackets. Eighty human premolars were bonded with premolar stainless steel brackets as per manufacturer's instructions. The teeth were divided into 4 groups (n=20): Recycling and initial debonding was not done in Control group (Group I). After initial bonding, the brackets in the rest of the three experimental groups were debonded and recycled by following methods: (i) Sandblasting (Group II) (ii) Sandblasting /direct flaming (Group III) (iii) Sandblasting /direct flaming /acid bath solution (Group IV). Further the recycled brackets were bonded. The specimens were then subjected to testing in a Universal machine. The evaluation of the variation of the shear bond strength (SBS) among test groups was done using one-way ANOVA test and inter-experimental group comparison was done by Newman-Keuls multiple post hoc procedure. Group I (8.6510±1.3943MPa) showed the highest bond strength followed by Group II (5.0185±0.9758MPa), Group IV (2.30±0.65MPa) and Group III (2.0455± 0.6196MPa). Statistically significant variations existed in the shear bond strength (SBS) in all groups analyzed except between Group III and Group IV. The following conclusions were drawn from the study: 1. Shear bond strength of new brackets is significantly higher than the recycled brackets. 2. Brackets sandblasted with 90µm aluminium oxide particle air-abrasion showed significantly higher shear bond strength compared to direct flaming/sandblasting and direct flaming/sandblasting/acid bath solution. 3. Sandblasting with 90µm aluminium oxide particle air-abrasion is the simplest, most efficient and hence, the preferred method of recycling debonded brackets. Key words: Orthodontic bracket, recycling, shear bond strength.

Hydrogen bonding between hydrides of the upper-right part of the periodic table

NASA Astrophysics Data System (ADS)

Simončič, Matjaž; Urbic, Tomaz

2018-05-01

One of the most important electrostatic interactions between molecules is most definitely the hydrogen bond. Understanding the basis of this interaction may offer us the insight needed to understand its effect on the macroscopic scale. Hydrogen bonding is for example the reason for anomalous properties in compounds like water and naturally life as we know it. The strength of the bond depends on numerous factors, among them the electronegativity of participating atoms. In this work we calculated the strength of hydrogen bonds between hydrides of the upper-right part of the periodic table (C, N, O, F, P, S, Cl, As, Se, Br) using quantum-chemical methods. The aim was to determine what influences the strength of strong and weak hydrogen bonds in simple hydrides. Various relationships were checked. A relation between the strength of the bond and the electronegativity of the participating atoms was found. We also observed a correlation between the strength of hydrogen bonds and the inter-atomic distances, along with the dependence on the charge transfer on the atom of the donor. We also report characteristic geometries of different dimers.

Rubbing time and bonding performance of one-step adhesives to primary enamel and dentin.

PubMed

Botelho, Maria Paula Jacobucci; Isolan, Cristina Pereira; Schwantz, Júlia Kaster; Lopes, Murilo Baena; Moraes, Rafael Ratto de

2017-01-01

This study investigated whether increasing the concentration of acidic monomers in one-step adhesives would allow reducing their application time without interfering with the bonding ability to primary enamel and dentin. Experimental one-step self-etch adhesives were formulated with 5 wt% (AD5), 20 wt% (AD20), or 35 wt% (AD35) acidic monomer. The adhesives were applied using rubbing motion for 5, 10, or 20 s. Bond strengths to primary enamel and dentin were tested under shear stress. A commercial etch-and-rinse adhesive (Single Bond 2; 3M ESPE) served as reference. Scanning electron microscopy was used to observe the morphology of bonded interfaces. Data were analysed at p<0.05. In enamel, AD35 had higher bond strength when rubbed for at least 10 s, while application for 5 s generated lower bond strength. In dentin, increased acidic monomer improved bonding only for 20 s rubbing time. The etch-and-rinse adhesive yielded higher bond strength to enamel and similar bonding to dentin as compared with the self-etch adhesives. The adhesive layer was thicker and more irregular for the etch-and-rinse material, with no appreciable differences among the self-etch systems. Overall, increasing the acidic monomer concentration only led to an increase in bond strength to enamel when the rubbing time was at least 10 s. In dentin, despite the increase in bond strength with longer rubbing times, the results favoured the experimental adhesives compared to the conventional adhesive. Reduced rubbing time of self-etch adhesives should be avoided in the clinical setup.

Influence of crosshead speed on micro-tensile bond strength of two-step adhesive systems.

PubMed

Yamaguchi, Kanako; Miyazaki, Masashi; Takamizawa, Toshiki; Tsubota, Keishi; Rikuta, Akitomo

2006-05-01

The purpose of this study was to determine the influence of crosshead speed on the micro-tensile bond strength of two separate adhesive systems to dentin. The systems used were the Clearfil SE Bond (Kuraray Medical) and the Single Bond (3M ESPE) combined with a resin composite Clearfil AP-X (Kuraray Medical). Dentin surfaces of bovine madibular incisors were primed with self-etching primer followed by air blowing for Clearfil SE Bond, or etched with phosphoric acid followed by rinsing with distilled water for Single Bond, and adhesive was applied. The resin composite was then built up in three layers and light activated. After 24 h storage in water, specimens were sectioned and trimmed to a cross-sectional area of 1 mm(2) and subjected to a micro-tensile bond-strength test. Ten samples per test group were tested at crosshead speeds of 0.5, 1.0, 5.0 and 10.0 mm/min. Micro-tensile bond-strength values (in MPa) were calculated from the peak load at failure divided by the specimen surface area. Two-way ANOVA was performed at the 0.05 probability level. The mean dentin bond strength at different crosshead speeds ranged from 34.6 to 37.1MPa for Clearfil SE Bond and from 44.3 to 50.4 MPa for Single Bond. There was no significant difference among the same adhesive systems with the different crosshead speeds tested. The influence of the crosshead speed might be negligible when measuring micro-tensile bond strengths.

Comparative evaluation of compressive strength, diametral tensile strength and shear bond strength of GIC type IX, chlorhexidine-incorporated GIC and triclosan-incorporated GIC: An in vitro study.

PubMed

Jaidka, Shipra; Somani, Rani; Singh, Deepti J; Shafat, Shazia

2016-04-01

To comparatively evaluate the compressive strength, diametral tensile strength, and shear bond strength of glass ionomer cement type IX, chlorhexidine-incorporated glass ionomer cement, and triclosan-incorporated glass ionomer cement. In this study, glass ionomer cement type IX was used as a control. Chlorhexidine diacetate, and triclosan were added to glass ionomer cement type IX powder, respectively, in order to obtain 0.5, 1.25, and 2.5% concentrations of the respective experimental groups. Compressive strength, diametral tensile strength, and shear bond strength were evaluated after 24 h using Instron Universal Testing Machine. The results obtained were statistically analyzed using the independent t-test, Dunnett test, and Tukey test. There was no statistical difference in the compressive strength, diametral tensile strength, and shear bond strength of glass ionomer cement type IX (control), 0.5% triclosan-glass ionomer cement, and 0.5% chlorhexidine-glass ionomer cement. The present study suggests that the compressive strength, diametral tensile strength, and shear bond strength of 0.5% triclosan-glass ionomer cement and 0.5% chlorhexidine-glass ionomer cement were similar to those of the glass ionomer cement type IX, discernibly signifying that these can be considered as viable options for use in pediatric dentistry with the additional value of antimicrobial property along with physical properties within the higher acceptable range.

Effect of dimethyl sulfoxide wet-bonding technique on hybrid layer quality and dentin bond strength.

PubMed

Stape, Thiago Henrique Scarabello; Tjäderhane, Leo; Marques, Marcelo Rocha; Aguiar, Flávio Henrique Baggio; Martins, Luís Roberto Marcondes

2015-06-01

This study examined the effect of a dimethyl sulfoxide (DMSO) wet bonding technique on the resin infiltration depths at the bonded interface and dentin bond strength of different adhesive systems. Flat dentin surfaces of 48 human third molars were treated with 50% DMSO (experimental groups) or with distilled water (controls) before bonding using an etch-and-rinse (SBMP: Scotchbond Multi-Purpose, 3M ESPE) or a self-etch (Clearfil: Clearfil SE Bond, Kuraray) adhesive system. The restored crown segments (n=12/group) were stored in distilled water (24h) and sectioned for interfacial analysis of exposed collagen using Masson's Trichrome staining and for microtensile bond strength testing. The extent of exposed collagen was measured using light microscopy and a histometric analysis software. Failure modes were examined by SEM. Data was analyzed by two-way ANOVA followed by Tukey Test (α=0.05). The interaction of bonding protocol and adhesive system had significant effects on the extension of exposed collagen matrix (p<0.0001) and bond strength (p=0.0091). DMSO-wet bonding significantly reduced the extent of exposed collagen matrix for SBMP and Clearfil (p<0.05). Significant increase in dentin bond strength was observed on DMSO-treated specimens bonded with SBMP (p<0.05), while no differences were observed for Clearfil (p>0.05). DMSO-wet bonding was effective to improve the quality of resin-dentin bonds of the tested etch-and-rinse adhesives by reducing the extent of exposed collagen matrix at the base of the resin-dentin biopolymer. The improved penetration of adhesive monomers is reflected as an increase in the immediate bond strength when the DMSO-wet bonding technique is used with a water-based etch-and-rinse adhesive. Copyright © 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Bond Strength of Composite to Dentin using Resin-Modified Glass Ionomers as Bonding Agents

DTIC Science & Technology

2016-03-02

59 MDW/SGVU SUBJECT: Professional Presentation Approval 2 MAR 20 16 l. Your paper, entitl ed Bond Strength of Composite to Dentin using Resin...Modified G lass Ionomers as Bonding Agents presented at Journal of Dental Research with MDWI 41- 108, and has been assigned local fi le #16086. 2...Vandewalle /Civ/SGDTG (59th CSPG/SGVU) DECS I 5-009 PROTOCOL TITLE Bond Strength of Composite to Dentin using Resin-modified Glass lonomers as

Effects of green tea on the shear bond strength of orthodontic brackets after in-office vital bleaching.

PubMed

Berger, Sandrine Bittencourt; Guiraldo, Ricardo Danil; Lopes, Murilo Baena; Oltramari-Navarro, Paula Vanessa; Fernandes, Thais Maria; Schwertner, Renata de Castro Alves; Ursi, Wagner José Silva

2016-01-01

The application of bleaching agents before placement of resin-bonded fixed appliances significantly, but temporarily, reduces bond strength to tooth structure. Antioxidants have been studied as a means to remove residual oxygen that compromises bonding to bleached enamel. This in vitro study evaluated whether green tea (GT) could restore the shear bond strength between bonded orthodontic brackets and bleached enamel. Six experimental groups were compared: group 1, no bleaching plus bracket bonding (positive control); group 2, bleaching with 35% hydrogen peroxide (HP) plus bracket bonding (negative control); group 3, 35% HP plus 10% sodium ascorbate (SA) plus bracket bonding; group 4, 35% HP plus 10% GT plus bracket bonding; group 5, no bleaching plus 10% SA plus bracket bonding; group 6, no bleaching plus 10% GT plus bracket bonding. Results suggested that GT, like SA, may be beneficial for bracket bonding immediately after bleaching.

Selective Acid Etching Improves the Bond Strength of Universal Adhesive to Sound and Demineralized Enamel of Primary Teeth.

PubMed

Antoniazzi, Bruna Feltrin; Nicoloso, Gabriel Ferreira; Lenzi, Tathiane Larissa; Soares, Fabio Zovico Maxnuck; Rocha, Rachel de Oliveira

To evaluate the influence of enamel condition and etching strategy on bond strength of a universal adhesive in primary teeth. Thirty-six primary molars were randomly assigned to six groups (n = 6) according to the enamel condition (sound [S] and demineralized [DEM]/cariogenic challenge by pH cycling prior to restorative procedures) and adhesive system (Scotchbond Universal Adhesive [SBU]) used in either etch-and-rinse (ER) or selfetching (SE) mode, with Clearfil SE Bond as the self-etching control. The adhesives were applied to flat enamel surfaces and composite cylinders (0.72 mm2) were built up. After 24-h storage in water, specimens were subjected to the microshear test. Bond strength (MPa) data were analyzed using two-way ANOVA and Tukey's post-hoc tests (α = 0.05). Significant differences were found considering the factors adhesive system (p = 0.003) and enamel condition (p = 0.001). Demineralized enamel negatively affected the bond strength, with μSBS values approximately 50% lower than those obtained for sound enamel. SBU performed better in etch-and-rinse mode, and the bond strength found for SBU applied in self-etching mode was similar to that of CSE. Enamel etching with phosphoric acid improves the bond strength of a universal adhesive system to primary enamel. Demineralized primary enamel results in lower bond strength.

Increased fracture toughness of graphite-epoxy composites through intermittent interlaminar bonding. [Mylar interlayer

NASA Technical Reports Server (NTRS)

Felbeck, D. K.; Jea, L. C.

1980-01-01

Intermittent interlaminar bonding, which can lead to a large increase in the fracture surface area, was achieved through the introduction of thin perforated Mylar between the layers of a multi-layer continuous-filament graphite-epoxy composite. For the best optimum condition included in this study, fracture toughness was increased from about 100 kJ/sq m for untreated specimens to an average of about 500 kJ/sq m, while tensile strength dropped from 500 MPa to 400 MPa, and elastic modulus remained the same at about 75 GPa. An approximate analysis is presented to explain the observed improvement in toughness.

Bonding quality of contemporary dental cements to sandblasted esthetic crown copings.

PubMed

Abdelaziz, Khalid M; Al-Qahtani, Nasser M; Al-Shehri, Abdulrahman S; Abdelmoneam, Adel M

2012-05-01

To evaluate the shear bond strength of current luting cements to sandblasted crown-coping substrates. Specimens of nickel-chromium, pressable glass ceramic, and zirconia crown-coping substrates were sandblasted in three groups (n = 30 each) with 50 (group 1), 110 (group 2), and 250 μm (group 3) alumina particles at a pressure of 250 kPa. Cylinders of glass ionomer, universal resin, and self-adhesive resin cements were then built up on the sandblasted substrate surfaces of each group (n = 10). All bonded specimens were stressed to evaluate the cement-substrate shear bond strength. Both the mode and incidence of bond failure were also considered. No difference was noticed between all test groups in terms of cement-substrate bond strength. In comparison to self-adhesive type, the universal resin cement provided lower bond strengths to both metal and glass-ceramic substrates in group 1. The self-adhesive resin cement provided the highest bond strengths to the zirconia substrates in groups 2 and 3. The adhesive type of bond failure was common in the metal and zirconia substrates in all groups. Cement-substrate bonding quality is not affected by the size of sandblasting particles. Resin cements bond better to different coping substrates. Self-adhesive resin cement is the best choice to bond zirconia-based substrates. © 2011 Blackwell Publishing Asia Pty Ltd.

Bonding resin thixotropy and viscosity influence on dentine bond strength.

PubMed

Niem, Thomas; Schmidt, Alexander; Wöstmann, Bernd

2016-08-01

To investigate the influence of bonding resin thixotropy and viscosity on dentine tubule penetration, blister formation and consequently on dentine bond strength as a function of air-blowing pressure (air-bp) intensity. Two HEMA-free, acetone-based, one-bottle self-etch adhesives with similar composition except disparate silica filler contents and different bonding resin viscosities were investigated. The high-filler-containing adhesive (G-Bond) featured a lower viscous bonding resin with inherent thixotropic resin (TR) properties compared to the low-filler-containing adhesive (iBond) exhibiting a higher viscous bonding resin with non-thixotropic resin (NTR) properties. Shear bond strength tests for each adhesive with low (1.5bar; 0.15MPa; n=16) and high (3.0bar; 0.30MPa; n=16) air-bp application were performed after specimen storage in distilled water (24h; 37.0±1.0°C). Results were analysed using a Student's t-test to identify statistically significant differences (p<0.05). Fracture surfaces of TR adhesive specimens were morphologically characterised by SEM. Statistically significant bond strength differences were obtained for the thixotropic resin adhesive (high-pressure: 24.6MPa, low-pressure: 9.6MPa). While high air-bp specimens provided SEM images revealing resin-plugged dentine tubules, resin tags and only marginally blister structures, low air-bp left copious droplets and open dentine tubules. In contrast, the non-thixotropic resin adhesive showed no significant bond strength differences (high-pressure: 9.3MPa, low-pressure: 7.6MPa). A pressure-dependent distinct influence of bonding resin thixotropy and viscosity on dentine bond strength has been demonstrated. Stronger adhesion with high air-bp application is explained by improved resin fluidity and facilitated resin penetration into dentine tubules. Filler particles used in adhesive systems may induce thixotropic effects in bonding resin layers, accounting for improved free-flowing resin properties. In combination with high air-bp this effect allows an easy plugging of dentine tubules and elimination of blister structures, both resulting in superior dentine bond strength. Copyright © 2016 Elsevier Ltd. All rights reserved.

Influence of enamel surface preparation on composite bond strength.

PubMed

Matos, Adriana Bona; Tate, William H; Powers, John M

2003-09-01

To evaluate the influence of air-particle abrasion and treatments on in vitro tensile bond strength of resin composite bonded to human enamel was evaluated using a single-bottle adhesive. Human teeth were divided into 12 groups of three treatments (none, 27-microm Al2O3 air-particle abrasion, 50-microm Al2O3 air-particle abrasion) and four conditioners [none, phosphoric acid (PA), NRC (no-rinse conditioner), and PA/NRC]. Bonding agent (Prime & Bond NT) and a resin composite (TPH Spectrum) were applied as inverted cones. Specimens were stored for 24 hours at 37 degrees C and debonded in tension using a testing machine at 0.5 mm/minute. Phosphoric acid treatment used with Prime & Bond NT produced the best bond strengths (24 MPa) to enamel for surfaces treated with 27-microm air-particle abrasion and for surfaces not treated with air-particle abrasion (control). With one exception, air-particle abraded surfaces resulted in bond strengths between 9 to 16 MPa. NRC with or without the use of phosphoric acid in general did not improve tensile bond strength to enamel when compared to surfaces not treated with NRC.

Influence of drying time and temperature on bond strength of contemporary adhesives to dentine.

PubMed

Garcia, Fernanda C P; Almeida, Júlio C F; Osorio, Raquel; Carvalho, Ricardo M; Toledano, Manuel

2009-04-01

To evaluate the bond strength (microTBS) of self-etching adhesives in different solvent evaporation conditions. Flat dentine surfaces from extracted human third molars were bonded with: (1) 2 two-steps self-etching adhesives (Clearfil SE Bond-CSEB); (Protect Bond-PB) and (2) 2 one-step self-etch systems (Adper Prompt L Pop-ADPLP); (Xeno III-XIII). Bonded dentine surfaces were air-dried for 5s, 20s, 30s or 40s at either 21 degrees C or 38 degrees C. Composite build-ups were constructed incrementally. After storage in water for 24h at 37 degrees C, the specimens were prepared for microtensile bond strength testing. Data were analyzed by two-way ANOVA and Student-Newman-Keuls at alpha=0.05. CSEB and PB performed better at warm temperature with only 20s of air-blowing. The bond strength increased when XIII was performed at warm temperature at 40s air-blowing. Extended air-blowing not affect the performance of ADPLP, except at 30s air-blowing time at warm temperature. The use of a warm air-dry stream seems to be a clinical tool to improve the bond strength to self-etching adhesives.

Development of an easy-debonding orthodontic adhesive using thermal heating.

PubMed

Tsuruoka, Takashi; Namura, Yasuhiro; Shimizu, Noriyoshi

2007-01-01

We produced experimentally a new bonding material that consisted of a mixture of a base resin (4-META/MMA-TBB resin adhesive) and thermoexpandable microcapsules for safe, easy debonding. Microcapsules in the base resin would start expansion at 80 degrees C, leading to a remarkable decrease in bond strength. Stainless steel brackets were bonded to bovine permanent mandibular incisors using bonding materials containing the microcapsules at different contents. After thermal cycling or heating, the shear bond strength of the brackets was measured. Shear bond strength of the bonding materials containing 30-40 wt% microcapsules decreased to about one-third or one-fifth that of the base resin on heating. Heating the brackets for eight seconds increased the temperature in the pulp chamber by 2 degrees C, which should not induce pulp damage. Results obtained suggested that the new bonding material should prove useful for removing brackets easily at the time of bracket debonding without any pain or enamel cracks, while maintaining the bonding strength during active orthodontic treatment.

Behavior of fiber reinforced mortar joints in masonry walls subjected to in-plane shear and out-of-plane bending

NASA Astrophysics Data System (ADS)

Armwood, Catherine K.

In this project, 26 fiber-reinforced mortar (FRM) mixtures are evaluated for their workability and strength characteristics. The specimens tested include two control mixtures and 24 FRMs. The mixtures were made of two types of binders; Type N Portland cement lime (Type N-PCL) and Natural Hydrated Lime 5 (NHL5); and 6 fiber types (5 synthetic fibers and one organic). When tested in flexure, the results indicate that majority of the synthetic fiber mixtures enhanced the performance of the mortar and the nano-nylon and horse hair fibers were the least effective in improving the mortar's modulus of rupture, ductility, and energy absorption. Four FRMs that improved the mortar's mechanical properties most during the flexural strength test were then used to conduct additional experiments. The FRM's compressive strength, as well as flexural and shear bond strength with clay and concrete masonry units were determined. Those four mixtures included Type N-PCL as the binder and 4 synthetic fibers. They were evaluated at a standard laboratory flow rate of 110% +/- 5% and a practical field flow rate of 130% +/- 5%. Results indicate that the use of fibers decreases the compressive strength of the mortar most of the time. However, the bond strength test results were promising: 81% of the FRM mixtures increased the flexural bond strength of the prism. The mixtures at 110 +/- 5% flow rate bonded better with concrete bricks and those ate 130+/-5% flow rate bonded better with clay bricks. The results of the shear bond strength show 50% of the FRM mixtures improved the shear bond strength. The FRM mixtures at 110+/-5% flow rate bonded with clay units provided the most improvement in shear bond strength compared to control specimen results. Along with detailed discussions and derived conclusions of these experiments, this dissertation includes recommendations for the most feasible FRM for different applications.

Evaluation of the Shear Bond Strength of Composite Resin to Wet and Dry Enamel Using Dentin Bonding Agents Containing Various Solvents

PubMed Central

Ramarao, Sathyanarayanan; John, Bindu Meera; Rajesh, Praveen; Swatha, S

2017-01-01

Introduction Bonding of composite resin to dentin mandates a wet substrate whereas, enamel should be dry. This may not be easily achievable in intracoronal preparations where enamel and dentin are closely placed to each other. Therefore, Dentin Bonding Agents (DBA) are recommended for enamel and dentinal bonding, where enamel is also left moist. A research question was raised if the “enamel-only” preparations will also benefit from wet enamel bonding and contemporary DBA. Aim The aim of this study was to compare the shear bond strengths of composite resin, bonded to dry and wet enamel using fifth generation DBA (etch and rinse system) containing various solvents such as ethanol/water, acetone and ethanol. Materials and Methods The crowns of 120 maxillary premolars were split into buccal and lingual halves. They were randomly allocated into four groups of DBA: Group 1-water/ethanol based, Group 2-acetone based, Group 3-ethanol based, Group 4-universal bonding agent (control group). The buccal halves and lingual halves were bonded using the wet bonding and dry bonding technique respectively. After application of the DBAs and composite resin build up, shear bond strength testing was done. Results Group 1 (ethanol/water based ESPE 3M, Adper Single Bond) showed highest bond strength of (23.15 MPa) in dry enamel. Group 2 (acetone based Denstply, Prime and Bond NT, showed equal bond strength in wet and dry enamel condition (18.87 MPa and 18.02 MPa respectively). Conclusion Dry enamel bonding and ethanol/water based etch and rinse DBA can be recommended for “enamel-only” tooth preparations. PMID:28274042

Effect of double-layer application on dentin bond durability of one-step self-etch adhesives.

PubMed

Taschner, M; Kümmerling, M; Lohbauer, U; Breschi, L; Petschelt, A; Frankenberger, R

2014-01-01

The aim of this in vitro study was 1) to analyze the influence of a double-layer application technique of four one-step self-etch adhesive systems on dentin and 2) to determine its effect on the stability of the adhesive interfaces stored under different conditions. Four different one-step self-etch adhesives were selected for the study (iBondSE, Clearfil S(3) Bond, XenoV(+), and Scotchbond Universal). Adhesives were applied according to manufacturers' instructions or with a double-layer application technique (without light curing of the first layer). After bonding, resin-dentin specimens were sectioned for microtensile bond strength testing in accordance with the nontrimming technique and divided into 3 subgroups of storage: a) 24 hours (immediate bond strength, T0), b) six months (T6) in artificial saliva at 37°C, or c) five hours in 10 % NaOCl at room temperature. After storage, specimens were stressed to failure. Fracture mode was assessed under a light microscope. At T0, iBond SE showed a significant increase in microtensile bond strength when the double-application technique was applied. All adhesive systems showed reduced bond strengths after six months of storage in artificial saliva and after storage in 10% NaOCl for five hours; however at T6, iBond SE, Clearfil S(3) Bond, and XenoV(+) showed significantly higher microtensile bond strength results for the double-application technique compared with the single-application technique. Scotchbond Universal showed no difference between single- or double-application, irrespective of the storage conditions. The results of this study show that improvements in bond strength of one-step self-etch adhesives by using the double-application technique are adhesive dependent.

Effect of Er,Cr:YSGG laser, air abrasion, and silane application on repaired shear bond strength of composites.

PubMed

Cho, S D; Rajitrangson, P; Matis, B A; Platt, J A

2013-01-01

Aged resin composites have a limited number of carbon-carbon double bonds to adhere to a new layer of resin. Study objectives were to 1) evaluate various surface treatments on repaired shear bond strength between aged and new resin composites and 2) to assess the influence of a silane coupling agent after surface treatments. Eighty disk-shape resin composite specimens were fabricated and thermocycled 5000 times prior to surface treatment. Specimens were randomly assigned to one of the three surface treatment groups (n=20): 1) air abrasion with 50-μm aluminum oxide, 2) tribochemical silica coating (CoJet), or 3) Er,Cr:YSGG (erbium, chromium: yttrium-scandium-gallium-garnet) laser or to a no-treatment control group (n=20). Specimens were etched with 35% phosphoric acid, rinsed, and dried. Each group was divided into two subgroups (n=10): A) no silanization and B) with silanization. The adhesive agent was applied and new resin composite was bonded to each conditioned surface. Shear bond strength was evaluated and data analyzed using two-way analysis of variance (ANOVA). Air abrasion with 50-μm aluminum oxide showed significantly higher repair bond strength than the Er,Cr:YSGG laser and control groups. Air abrasion with 50-μm aluminum oxide was not significantly different from tribochemical silica coating. Tribochemical silica coating had significantly higher repair bond strength than Er,Cr:YSGG laser and the control. Er,Cr:YSGG laser and the control did not have significantly different repair bond strengths. Silanization had no influence on repair bond strength for any of the surface treatment methods. Air abrasion with 50-μm aluminum oxide and tribochemical silica followed by the application of bonding agent provided the highest repair shear bond strength values, suggesting that they might be adequate methods to improve the quality of repairs of resin composites.

Casein phosphopeptide-amorphous calcium phosphate and shear bond strength of adhesives to primary teeth enamel.

PubMed

Farokh Gisovar, Elham; Hedayati, Nassim; Shadman, Niloofar; Shafiee, Leila

2015-02-01

CPP-ACP (Phosphopeptide-Amorphous Calcium Phosphate) has an important role in caries prevention in pediatric patients. This study was done, because of the great use of CPP-ACP and the need for restoration for teeth treated with CPP-ACP as well as the importance of shear bond strength of adhesives in the success of restorations. This study aimed to evaluate the effect of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) on shear bond strength of dental adhesives to enamel of primary teeth molars. This in vitro study was conducted on 180 extracted primary molars. They were randomly divided into 6 groups and each group was divided into 2 subgroups (treated with CPP-ACP and untreated). In subgroups with CPP-ACP, enamel was treated with CPP-ACP paste 1 h/d for 5 days. Types of adhesives that were evaluated in this study were Tetric N-Bond, AdheSE, AdheSE One F, single Bond 2, SE Bond, and Adper Prompt L-Pop. Shear bond strength was tested with a universal testing machine and mode of failure was evaluated under stereomicroscope. Data were analyzed by T test, 2-way analysis of variance (ANOVA), Tukey and Fisher exact test using SPSS18. P < 0.05 was considered as significance level. Shear bond strengths of different adhesive systems to enamel of primary teeth treated and untreated with CPP-ACP showed no significant difference (P > 0.05). Mode of failure in all groups regardless of CPP-ACP administration was mainly adhesive type. Our results indicated that CPP-ACP did not affect shear bond strength of studied adhesives to primary teeth enamel. To have a successful and durable composite restoration, having a high strength bonding is essential. Considering the wide use of CPP-ACP in preventing tooth decay and the role of adhesive shear bond strength (SBS) in success of composite restoration, we conducted the present study to evaluate the effect of CPP-ACP on the SBS of adhesives to primary teeth enamel.

Effect of surface treatments on the bond strengths of facing composite resins to zirconia copings.

PubMed

Tsumita, M; Kokubo, Y; Kano, T

2012-09-01

The present study evaluated and compared the bond strength between zirconia and facing composite resin using different surface conditioning methods before and after thermocycling. Four primers, three opaque resins, and two facing composite resins were used, and 10 surface treatment procedures were conducted. The bond strength was measured before and after 4,000 cycles of thermocycling. The mean values of each group were statistically analyzed using one-way analysis of variance (ANOVA). The bond strengths of facing composite resins to zirconia after various treatments varied depending on the primers, opaque resins, body resins, and thermocycling. The application of primers and opaque resins to the zirconia surface after sandblasting is expected to yield strong bond strength of the facing composite resin (Estenia CG&B) even after thermocycling.

The effect of water storage, elapsed time and contaminants on the bond strength and interfacial polymerization of a nanohybrid composite.

PubMed

Perriard, Jean; Lorente, Maria Cattani; Scherrer, Susanne; Belser, Urs C; Wiskott, H W Anselm

2009-12-01

To systematically characterize the effect of time lapse, water storage, and selected contaminants on the bond strength of a nanofilled dental composite. Half-dumbbell-shaped samples were fabricated out of light-polymerizing composite resin. To function as substrates they were aged for 30 days in water. Prior to bonding, the substrates' surfaces were subjected to the following treatments: 1) Removing a 0.2- to 0.4-mm layer using a fluted carbide bur; 2) grit blasting with 50 microm alumina particles; 3) etching with phosphoric acid gel; 4) grit blasting followed by etching; 5) blasting with tribochemical particles followed by silane application; 6) sanding with 400-grit paper, air aging of the adherent half-sample before bonding; 7) surface contamination with saliva; 8) surface contamination with blood. In each group (n = 30), freshly polymerized (except in group 6) adherent half-samples were bonded to the substrate half-samples by a layer of unfilled adhesive resin. Fifteen full dumbbell-shaped specimens were subjected to tensile testing after 1 h and 15 after 7 days water storage. In a positive control group, freshly cured half-samples were bonded shortly after fabrication. The tensile strength was analyzed using Weibull statistics and presented in terms of the material's characteristic strength and shape parameter. Fractographs of the two weakest and strongest samples of each group were produced. The surfaces were searched to locate hackle, wake hackle and the origin of the fracture. Surface roughness and time lapse increased the bond strength of the repaired specimens. All groups in which surface roughness was produced before bonding increased in repair strength. Post-bonding aging improved strength. Fractographs yielded interpretable data whenever larger surfaces of single phase bonding resin were present. 1) Roughening and etching an aged composite's surface prior to applying a coat of unfilled resin and the filled material increases repair bond strength by up to 100%. 2) The repair bond strength of a roughened aged composite is 25% to 30% inferior to the tensile strength of solid specimens. 3) After 7 days' storage in water, no detrimental effect could be seen from saliva or blood contamination if the surfaces were properly rinsed.

Tensile and shear bond strength of hard and soft denture relining materials to the conventional heat cured acrylic denture base resin: An In-vitro study.

PubMed

Lau, Mayank; Amarnath, G S; Muddugangadhar, B C; Swetha, M U; Das, Kopal Anshuraj Ashok Kumar

2014-04-01

The condition of the denture bearing tissues may be adversely affected by high stress concentration during function. Chairside Denture (Hard and Soft) reliners are used to distribute forces applied to soft tissues during function. Tensile and shear bond strength has been shown to be dependent on their chemical composition. A weak bond could harbor bacteria, promote staining and delamination of the lining material. To investigate tensile and shear bond strength of 4 different commercially available denture relining materials to conventional heat cured acrylic denture base resin. 4 mm sections in the middle of 160 Acrylic cylindrical specimens (20 mm x 8 mm) were removed, packed with test materials (Mollosil, G C Reline Soft, G C Reline Hard (Kooliner) and Ufi Gel Hard and polymerized. Specimens were divided into 8 groups of 20 each. Tensile and shear bond strength to the conventional heat cured acrylic denture base resin were examined by Instron Universal Tensile Testing Machine using the equation F=N/A (F-maximum force exerted on the specimen (Newton) and A-bonding area= 50.24 mm2). One-way ANOVA was used for multiple group comparisons followed by Bonferroni Test and Hsu's MCB for multiple pairwise comparisons to asses any significant differences between the groups. The highest mean Tensile bond strength value was obtained for Ufi Gel Hard (6.49+0.08 MPa) and lowest for G C Reline Soft (0.52+0.01 MPa). The highest mean Shear bond strength value was obtained for Ufi Gel Hard (16.19+0.1 MPa) and lowest for Mollosil (0.59+0.05 MPa). The Benferroni test showed a significant difference in the mean tensile bond strength and the mean shear bond strength when the two denture soft liners were compared as well as when the two denture hard liners were compared. Hsu's MCB implied that Ufi gel hard is better than its other closest competitors. The Tensile and Shear bond strength values of denture soft reliners were significantly lower than denture hard reliners. How to cite the article: Lau M, Amarnath GS, Muddugangadhar BC, Swetha MU, Das KA. Tensile and shear bond strength of hard and soft denture relining materials to the conventional heat cured acrylic denture base resin: An In-vitro study. J Int Oral Health 2014;6(2):55-61.

Effect of various commercially available mouthrinses on shear bond strength of orthodontic metal brackets: an in vitro study.

PubMed

Meeran, Nazeer Ahmed; George, Ashwin Mathew

2013-01-01

Alcohol is known to degrade and dissolve the bisphenol A glycidyl methacrylate present in the composite resin. The effect of alcohol containing mouthrinses on the shear bond strength of orthodontic metal brackets bonded with composite resin has not been verified until date and is the purpose of this study. The aims and objectives of the present study were to evaluate (1) Whether there is a significant difference in the shear bond strength of metal orthodontic brackets after the 1 year (12 h) and 2 years simulation (24 h) of mouth rinsing with 4 different commercially available mouthrinses (2 alcoholic and 2 alcohol-free mouthrinses) when compared to the control. (2) Whether alcohol containing mouthrinses have more adverse effect on the shear bond strength when compared with alcohol-free mouthrinses. (3) To assess the site of bond failure using adhesive remnant index. Experimental - laboratory based. A total of 100 upper premolars extracted for orthodontic purpose were collected immediately after extraction, cleared soft-tissue debris and blood and immediately stored in distilled water with 0.1% thymol crystals added to inhibit bacterial growth. Two alcohol containing mouthrinses and two alcohol-free mouthrinses were used and the bonded teeth were placed in the mouthrinses for a stipulated period of time (1 year simulation and 2 years simulation) and shear bond strength were tested using Lloyd Universal Testing Machine. The data were analyzed using analysis of variance and paired samples t-test. After the 1 year and 2 years simulation time, samples stored in alcohol containing mouthrinses showed lower bond strength (P < 0.05) when compared to samples stored in alcohol free mouthrinses and distilled water (control). Alcohol containing mouthrinses affect the shear bond strength of the metal orthodontic brackets bonded with composite resin (Transbond XT in the present study), more when compared with alcohol-free mouthrinses. It is, therefore, highly advisable to avoid alcohol containing mouthrinses in patients undergoing orthodontic treatment and use alcohol-free mouthrinses as adjuncts to regular oral hygiene procedures for maintaining good enamel integrity and periodontal health, without compromising the shear bond strength of the bonded metal brackets.

Comparison of shear bond strength of self-etch and self-adhesive cements bonded to lithium disilicate, enamel and dentin.

PubMed

Naranjo, Jennifer; Ali, Mohsin; Belles, Donald

2015-11-01

Comparison of shear bond strength of self-etch and self-adhesive cements bonded to lithium disilicate, enamel and dentin. With several self-adhesive resin cements currently available, there is confusion about which product and technique is optimal for bonding ceramic restorations to teeth. The objective of this study was to compare the shear bond strength of lithium disilicate cemented to enamel and dentin using 5 adhesive cements. 100 lithium disilicate rods were pretreated with 5% hydrofluoric acid, silane, and cemented to 50 enamel and 50 dentin surfaces using five test cements: Variolink II (etch-and-rinse) control group, Clearfil Esthetic (two step self-etch), RelyX Unicem, SpeedCEM, and BifixSE (self-adhesive). All specimens were stored (37 degrees C, 100% humidity) for 24 hours before testing their shear bond strength using a universal testing machine (Instron). Debonded surfaces were observed under a low-power microscope to assess the location and type of failure. The highest bond strength for both enamel and dentin were recorded for Variolink II, 15.1MPa and 20.4MPa respectively, and the lowest were recorded for BifixSE, 0.6MPa and 0.9MPa respectively. Generally, higher bond strengths were found for dentin (7.4MPa) than enamel (5.3MPa). Tukey's post hoc test showed no significant difference between Clearfil Esthetic and SpeedCem (p = 0.059), Unicem and SpeedCem (p = 0.88), and Unicem and BifixSE (p = 0.092). All cements bonded better to lithium disilicate than to enamel or dentin, as all bond failures occurred at the tooth/adhesive interface except for Variolink II. Bond strengths recorded for self-adhesive cements were very low compared to the control "etch and rinse" and self-etch systems. Further improvements are apparently needed in self-adhesive cements for them to replace multistep adhesive systems. The use of conventional etch and rinse cements such as Veriolink II should be preferred for cementing all ceramic restorations over self-adhesive cements until the bond strengths are improved.

Evaluation of bonding agent application on concrete patch performance.

DOT National Transportation Integrated Search

2014-08-01

The durability of partial depth repair is directly related to the bond strength between the repair material and existing : concrete. Bond strength development sensitivity to wait time with the use of bonding agents in partial depth repair was : inves...

DOE Office of Scientific and Technical Information (OSTI.GOV)

Samavatian, Majid, E-mail: m.samavatian@srbiau.ac.ir; Halvaee, Ayoub; Amadeh, Ahmad Ali

Joining mechanism of Ti/Al dissimilar alloys was studied during liquid state diffusion bonding process using Cu/Sn/Cu interlayer at 510 °C under vacuum of 7.5 × 10{sup −5} Torr for various bonding times. The microstructure and compositional changes in the joint zone were analyzed by scanning electron microscopy equipped with energy dispersive spectroscopy and X-ray diffraction. Microhardness and shear strength tests were also applied to study the mechanical properties of the joints. It was found that with an increase in bonding time, the elements of interlayer diffused into the parent metals and formed various intermetallic compounds at the interface. Diffusion processmore » led to the isothermal solidification and the bonding evolution in the joint zone. The results from mechanical tests showed that microhardness and shear strength values have a straight relation with bonding time so that the maximum shear strength of joint was obtained for a bond made with 60 min bonding time. - Highlights: • Liquid state diffusion bonding of Al2024 to Ti–6Al–4V was performed successfully. • Diffusion of the elements caused the formation of various intermetallics at the interface. • Microhardness and shear strength values have a straight relation with bonding time. • The maximum shear strength reached to 36 MPa in 60 min bonding time.« less

Shear Bond Strengths and Morphological Evaluation of Filled and Unfilled Adhesive Interfaces to Enamel and Dentine

PubMed Central

Mortazavi, Vajihesadat; Fathi, Mohammadhosein; Ataei, Ebrahim; Khodaeian, Niloufar; Askari, Navid

2012-01-01

In this laboratory study shear bond strengths of three filled and one unfilled adhesive systems to enamel and dentine were compared. Forty-eight extracted intact noncarious human mandibular molars were randomly assigned to two groups of 24 one for bonding to enamel and the other for bonding to dentine. Buccal and lingual surfaces of each tooth were randomly assigned for application of each one of filled (Prime & Bond NT (PBNT), Optibond Solo Plus (OBSP), and Clearfil SE Bond (CSEB)) and unfilled (Single Bond (SB)) adhesive systems (n = 12). A universal resin composite was placed into the translucent plastic cylinders (3 mm in diameter and 2 mm in length) and seated against the enamel and dentine surfaces and polymerized for 40 seconds. Shear bond strength was determined using a universal testing machine, and the results were statistically analyzed using two-way ANOVA, one-way ANOVA, t-test, and Tukey HSD post hoc test with a 5% level of significance.There were no statistically significant differences in bond strength between the adhesive systems in enamel, but CSEB and SB exhibited significantly higher and lower bond strength to dentine, respectively, than the other tested adhesive systems while there were no statistically significant differences between PBNT and OBSP. PMID:23209471

Relationship between enamel bond fatigue durability and surface free-energy characteristics with universal adhesives.

PubMed

Nagura, Yuko; Tsujimoto, Akimasa; Barkmeier, Wayne W; Watanabe, Hidehiko; Johnson, William W; Takamizawa, Toshiki; Latta, Mark A; Miyazaki, Masashi

2018-04-01

The relationship between enamel bond fatigue durability and surface free-energy characteristics with universal adhesives was investigated. The initial shear bond strengths and shear fatigue strengths of five universal adhesives to enamel were determined with and without phosphoric acid pre-etching. The surface free-energy characteristics of adhesive-treated enamel with and without pre-etching were also determined. The initial shear bond strength and shear fatigue strength of universal adhesive to pre-etched enamel were higher than those to ground enamel. The initial shear bond strength and shear fatigue strength of universal adhesive to pre-etched enamel were material dependent, unlike those to ground enamel. The surface free-energy of the solid (γ S ) and the hydrogen-bonding force (γSh) of universal adhesive-treated enamel were different depending on the adhesive, regardless of the presence or absence of pre-etching. The bond fatigue durability of universal adhesives was higher to pre-etched enamel than to ground enamel. In addition, the bond fatigue durability to pre-etched enamel was material dependent, unlike that to ground enamel. The surface free-energy characteristics of universal adhesive-treated enamel were influenced by the adhesive type, regardless of the presence or absence of pre-etching. The surface free-energy characteristics of universal adhesive-treated enamel were related to the results of the bond fatigue durability. © 2018 Eur J Oral Sci.

Influence of surface treatments on the shear bond strength of orthodontic brackets to porcelain

NASA Astrophysics Data System (ADS)

Wang, Cong; Zeng, Jishan; Wang, Shaoan; Yang, Zheng; Huang, Qian; Chen, Pixiu; Zhou, Shujuan; Liu, Xiaoqing

2008-11-01

The purpose of this study was to investigate the effect of various surface treatments after different storage time and thermocycling on the shear bond strength of orthodontic brackets to the feldspathic porcelain surfaces. 128 disc-shaped porcelain specimens were randomly assigned to the following surface treatments: 9.6% HFA, 9.6% HFA combined with silane, 50 μ aluminum trioxide sandblasting followed by silane and application of silane after 37% phosphoric acid. Metal or ceramic brackets were bonded onto each treated porcelain facet with light cured resin. The samples were stored in 37 °C water 1 day or 7 days, thermocycled 500 times from 5 to 55 °C. The shear bond strengths were measured (1 mm/min), and statistically analyzed. The bond failure sites were classified according to ARI system. The surface of the glazed, sandblasted, hydrofluoric and phosphoric acid etched porcelain were examined with SEM. All groups achieved reasonable bond strengths to withstand the application of orthodontic forces. Water storage for 7 days caused lower shear bond strength than that of 1 day. But there is no statistically significant difference between the two groups. The mean shear bond strength provided by ceramic bracket with mechanical retention had no statistical difference with that of metal bracket. Therefore, the optimal treatment for orthodontic brackets bonding to feldspathic porcelain was to apply phosphoric acid combined with silane.

Correlation of bond strength with surface roughness using a new roughness measurement technique.

PubMed

Winkler, M M; Moore, B K

1994-07-01

The correlation between shear bond strength and surface roughness was investigated using new surface measurement methods. Bonding agents and associated resin composites were applied to set amalgam after mechanically roughening its surface. Surface treatments were noe (as set against glass), 80 grit, and 600 grit abrasive paper. Surface roughness (R(a) as measured parallel and perpendicular (+) to the direction of the polishing scratches and true profile length were measured. A knife-edge was applied (rate = 2.54 mm/min) at the bonding agent/amalgam interface of each sample until failure. Coefficients of determination for mean bond strength vs either roughness (R(a), of profile length were significantly higher for measurements in parallel directions than for those measurements in (+) directions. The shear bond strength to set amalgam for a PENTA-containing adhesives system (L.D. Caulk Division) was not significantly different from that of a PENTA-free adhesive (3M Dental Products Division), even though PENTA has been reported to increase bond strength to nonprecious metals. The shear bond strength of resin composite to amalgam is correlated to surface roughness when it is measured parallel to the polishing scratches. This correlation is significantly lower when surface roughness is measured in the typical manner, perpendicular to the polishing scratches.

Effect of Self-Adhesive and Separate Etch Adhesive Dual Cure Resin Cements on the Bond Strength of Fiber Post to Dentin at Different Parts of the Root.

PubMed

Amiri, Ehsan Mohamadian; Balouch, Fariba; Atri, Faezeh

2017-05-01

Bonding of fiber posts to intracanal dentin is challenging in the clinical setting. This study aimed to compare the effect of self-adhesive and separate etch adhesive dual cure resin cements on the bond strength of fiber post to dentin at different parts of the root. This in-vitro experimental study was conducted on 20 single-rooted premolars. The teeth were decoronated at 1mm coronal to the cementoenamel junction (CEJ), and the roots underwent root canal treatment. Post space was prepared in the roots. Afterwards, the samples were randomly divided into two groups. In group 1, the fiber posts were cemented using Rely X Unicem cement, while in group 2, the fiber posts were cemented using Duo-Link cement, according to the manufacturer's instructions. The intracanal post in each root was sectioned into three segments of coronal, middle, and apical, and each cross-section was subjected to push-out bond strength test at a crosshead speed of 1mm/minute until failure. Push-out bond strength data were analyzed using independent t-test and repeated measures ANOVA. The bond strength at the middle and coronal segments in separate etch adhesive cement group was higher than that in self-adhesive cement group. However, the bond strength at the apical segment was higher in self-adhesive cement group compared to that in the other group. Overall, the bond strength in separate etch adhesive cement group was significantly higher than that in self-adhesive cement group (P<0.001). Bond strength of fiber post to intracanal dentin is higher after the use of separate etch adhesive cement compared to self-adhesive cement.

Bond strength of fiber-reinforced posts to deproteinized root canal dentin.

PubMed

Furuse, Adilson Yoshio; Cunha, Leonardo Fernandes; Baratto, Samantha Pugsley; Leonardi, Denise Piotto; Haragushiku, Gisele Aihara; Gonzaga, Carla Castiglia

2014-09-01

This study evaluated the push-out bond strength of cemented fiber posts after deproteinization of root canal dentin walls with NaOCl. The effect of the application of an antioxidant solution (sodium ascorbate) was also evaluated. A three-step etch-and-rinse (Scotch-bond - 3M Espe) and a one-step self-etching adhesive (Xeno III - Dentsply Caulk) were evaluated. Thirty bovine incisor roots were divided into 3 groups: a. Irrigation with physiologic solution (control). b. Deproteinization with 10 minutes irrigation of 5% NaOCl. c. Deproteinization with NaOCl followed by 10 minutes irrigation with 10% ascorbic acid. Fiber posts were cemented with a dual-cured cement (Rely X ARC - 3M ESPE). The push-out bond strength was evaluated after 24 hours of storage in distilled water. The data were analyzed with three-way ANOVA, one-way ANOVA and Tukey's test (α = 0.05). There were significant differences between groups (p < 0.05). The bond strength of Scotchbond was not influenced by the deproteinization. Xeno III showed a decrease in bond strength when deproteinized with 5% NaOCl (p < 0.05). For Xeno III, the subsequent irrigation with ascorbic acid was able to reverse the effect of the deproteinization. Considering the radicular thirds, the bond strength varied in the sequence-apical < middle < coronal. Only the all-in-one adhesive was influenced by the deproteinization. Considering the respective control groups, both systems showed similar bond strength results. The decreased bond strength of the self-etching adhesive following deproteinization seams to be related to the oxidant effect of the NaOCl solution and the subsequent irrigation with ascorbic acid was able to reverse the effect of the deproteinization.

Effect of Nd: YAG laser irradiation on surface properties and bond strength of zirconia ceramics.

PubMed

Liu, Li; Liu, Suogang; Song, Xiaomeng; Zhu, Qingping; Zhang, Wei

2015-02-01

This study investigated the effect of neodymium-doped yttrium aluminum garnet (Nd: YAG) laser irradiation on surface properties and bond strength of zirconia ceramics. Specimens of zirconia ceramic pieces were divided into 11 groups according to surface treatments as follows: one control group (no treatment), one air abrasion group, and nine laser groups (Nd: YAG irradiation). The laser groups were divided by applying with different output power (1, 2, or 3 W) and irradiation time (30, 60, or 90 s). Following surface treatments, the morphological characteristics of ceramic pieces was observed, and the surface roughness was measured. All specimens were bonded to resin cement. After, stored in water for 24 h and additionally aged by thermocycling, the shear bond strength was measured. Dunnett's t test and one-way ANOVA were performed as the statistical analyses for the surface roughness and the shear bond strength, respectively, with α = .05. Rougher surface of the ceramics could be obtained by laser irradiation with higher output power (2 and 3 W). However, cracks and defects were also found on material surface. The shear bond strength of laser groups was not obviously increased, and it was significantly lower than that of air abrasion group. No significant differences of the shear bond strength were found among laser groups treated with different output power or irradiation time. Nd: YAG laser irradiation cannot improve the surface properties of zirconia ceramics and cannot increase the bond strength of the ceramics. Enhancing irradiation power and extending irradiation time cannot induce higher bond strength of the ceramics and may cause material defect.

Effect of Different Anti-Oxidants on Shear Bond Strength of Composite Resins to Bleached Human Enamel

PubMed Central

Saladi, Hari Krishna; Bollu, Indira Priyadarshini; Burla, Devipriya; Ballullaya, Srinidhi Vishnu; Devalla, Srihari; Maroli, Sohani; Jayaprakash, Thumu

2015-01-01

Introduction The bond strength of the composite to the bleached enamel plays a very important role in the success and longevity of an aesthetic restoration. Aim The aim of this study was to compare and evaluate the effect of Aloe Vera with 10% Sodium Ascorbate on the Shear bond strength of composite resin to bleached human enamel. Materials and Methods Fifty freshly extracted human maxillary central incisors were selected and divided into 5 groups. Group I and V are unbleached and bleached controls groups respectively. Group II, III, IV served as experimental groups. The labial surfaces of groups II, III, IV, V were treated with 35% Carbamide Peroxide for 30mins. Group II specimens were subjected to delayed composite bonding. Group III and IV specimens were subjected to application of 10% Sodium Ascorbate and leaf extract of Aloe Vera following the Carbamide Peroxide bleaching respectively. Specimens were subjected to shear bond strength using universal testing machine and the results were statistically analysed using ANOVA test. Tukey (HSD) Honest Significant Difference test was used to comparatively analyse statistical differences between the groups. A p-value <0.05 is taken as statistically significant. Results The mean shear bond strength values of Group V showed significantly lower bond strengths than Groups I, II, III, IV (p-value <0.05). There was no statistically significant difference between the shear bond strength values of groups I, II, III, IV. Conclusion Treatment of the bleached enamel surface with Aloe Vera and 10% Sodium Ascorbate provided consistently better bond strength. Aloe Vera may be used as an alternative to 10% Sodium Ascorbate. PMID:26674656

The Effect of Food-Simulating Agents on the Bond Strength of Hard Chairside Reline Materials to Denture Base Resin.

PubMed

Fatemi, Farzaneh Sadat; Vojdani, Mahroo; Khaledi, Amir Ali Reza

2018-06-08

To investigate the influence of food-simulating agents on the shear bond strength between direct hard liners and denture base acrylic resin. In addition, mode of failure was evaluated. One hundred fifty cylindrical columns of denture base resin were fabricated and bonded to three types of hard reline materials (Hard GC Reline, Tokuyama Rebase II Fast, TDV Cold Liner Rebase). Specimens of each reline material were divided into five groups (n = 10) to undergo 12-day immersion in distilled water, 0.02 N citric acid aqueous solution, heptane, and 40% ethanol/water solution at 37°C. The control group was not immersed in any solution. The shear bond strength test was performed, and the failure mode was determined. Statistics were analyzed with two-way ANOVA and chi-square test (α = 0.05). Significant interaction was found between the hard liners and food simulating agents (p < 0.001). The shear bond strength of Tokuyama in 40% ethanol and TDV in heptane decreased significantly (p = 0.001, p < 0.001 respectively); however, none of the solutions could significantly affect the shear bond strength of Hard GC Reline (p = 0.208). The mixed failure mode occurred more frequently in Hard GC Reline compared with the other liners (p < 0.001) and was predominant in specimens with higher bond strength values (p = 0.012). Food simulating agents did not adversely affect the shear bond strength of Hard GC Reline; however, ethanol and heptane decreased the bond strength of Tokuyama and TDV, respectively. These findings may provide support to dentists to recommend restricted consumption of some foods and beverages for patients who have to use dentures relined with certain hard liners. © 2018 by the American College of Prosthodontists.

Enhancing integration of articular cartilage grafts via photochemical bonding.

PubMed

Arvayo, Alberto L; Wong, Ivan J; Dragoo, Jason L; Levenston, Marc E

2018-03-25

The integration of osteochondral grafts to native articular cartilage is critical as the lack of graft integration may lead to continued tissue degradation, poor load transfer and inadequate nutrient transport. Photochemical bonding promotes graft integration by activating a photosensitizer at the interface via a light source and avoids negative effects associated with other bonding techniques. We hypothesized that the bond strength depends on photosensitizer type and concentration in addition to light exposure. Photochemical bonding was evaluated using methylene blue (MB), a cationic phenothiazine photosensitizer, and two phthalocyanine photosensitizers, Al(III) phthalocyanine chloride tetrasulfonic acid (CASPc) and aluminum phthalocyanine chloride (AlPc). Exposure was altered by varying irradiation time for a fixed irradiance or by varying irradiance with a fixed irradiation time. MB was ineffective at producing bonding at the range of concentrations tested while CASPc produced a peak twofold bond strength increase over controls. AlPc produced substantial bonding at all concentrations with a peak 3.9-fold bond strength increase over controls. Parametric tests revealed that bond strength depended primarily on the total energy delivered to the bonding site rather than the rate of light delivery or light irradiance. Bond strength persisted for 1 week of in-vitro culture, which warrants further exploration for clinical applications. These studies indicate that photochemical bonding is a viable strategy for enhancing articular cartilage graft integration. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Comparison of shear bond strengths of conventional orthodontic composite and nano-ceramic restorative composite: an in vitro study.

PubMed

Nagar, Namit; Vaz, Anna C

2013-01-01

To compare the shear bond strength of a nano-ceramic restorative composite Ceram-X Mono(TM♦), a restorative resin with the traditional orthodontic composite Transbond XT(TM†) and to evaluate the site of bond failure using Adhesive Remnant Index. Sixty extracted human premolars were divided into two groups of 30 each. Stainless steel brackets were bonded using Transbond XT(TM†) (Group I) and Ceram-X Mono(TM♦) (Group II) according to manufacturer's protocol. Shear bond strength was measured on Universal testing machine at crosshead speed of 1 mm/minute. Adhesive Remnant Index scores were assigned to debonded brackets of each group. Data was analyzed using unpaired 't' test and Chi square test. The mean shear bond strength of Group I (Transbond XT(TM†)) was 12.89 MPa ± 2.19 and that of Group II (Ceram-X Mono(TM)) was 7.29 MPa ± 1.76. Unpaired 't' test revealed statistically significant differences amongst the shear bond strength of the samples measured. Chi-square test revealed statistically insignificant differences amongst the ARI scores of the samples measured. Ceram-X Mono(TM♦) had a lesser mean shear bond strength when compared to Transbond XT(TM†) which was statistically significant difference. However, the mean shear bond of Ceram X Mono was within the clinically acceptable range for bonding. Ceram-X Mono(TM†) and Transbond XT(TM†) showed cohesive fracture of adhesive in 72.6% and 66.6% of the specimens, respectively.

Evaluation of microtensile and tensile bond strength tests determining effects of erbium, chromium: yttrium-scandium-gallium-garnet laser pulse frequency on resin-enamel bonding.

PubMed

Yildirim, T; Ayar, M K; Yesilyurt, C; Kilic, S

2016-01-01

The aim of the present study was to compare two different bond strength test methods (tensile and microtensile) in investing the influence of erbium, chromium: yttrium-scandium-gallium-garnet (Er, Cr: YSGG) laser pulse frequency on resin-enamel bonding. One-hundred and twenty-five bovine incisors were used in the present study. Two test methods were used: Tensile bond strength (TBS; n = 20) and micro-TBS (μTBS; n = 5). Those two groups were further split into three subgroups according to Er, Cr: YSGG laser frequency (20, 35, and 50 Hz). Following adhesive procedures, microhybrid composite was placed in a custom-made bonding jig for TBS testing and incrementally for μTBS testing. TBS and μTBS tests were carried out using a universal testing machine and a microtensile tester, respectively. Analysis of TBS results showed that means were not significantly different. For μTBS, the Laser-50 Hz group showed the highest bond strength (P < 0.05), and increasing frequency significantly increased bond strength (P < 0.05). Comparing the two tests, the μTBS results showed higher means and lower standard deviations. It was demonstrated that increasing μTBS pulse frequency significantly improved immediate bond strength while TBS showed no significant effect. It can, therefore, be concluded that test method may play a significant role in determining optimum laser parameters for resin bonding.

Long-term Bond Strength between Layering Indirect Composite Material and Zirconia Coated with Silicabased Ceramics.

PubMed

Fushiki, Ryosuke; Komine, Futoshi; Honda, Junichi; Kamio, Shingo; Blatz, Markus B; Matsumura, Hideo

2015-06-01

This study evaluated the long-term shear bond strength between an indirect composite material and a zirconia framework coated with silica-based ceramics, taking the effect of different primers into account. A total of 165 airborne-particle abraded zirconia disks were subjected to one of three pretreatments: no pretreatment (ZR-AB), airborne-particle abrasion of zirconia coated with feldspathic porcelain (ZR-PO-AB), and 9.5% hydrofluoric acid etching of zirconia coated with feldspathic porcelain (ZR-PO-HF). An indirect composite material (Estenia C&B) was then bonded to the zirconia disks after they were treated with one of the following primers: Clearfil Photo Bond (CPB), Clearfil Photo Bond with Clearfil Porcelain Bond Activator (CPB + Activator), Estenia Opaque Primer (EOP), Porcelain Liner M Liquid B (PLB), or no priming (CON, control group). Shear bond strength was tested after 100,000 thermocycles, and the data were analyzed using the Steel-Dwass U-test (α = 0.05). For ZR-PO-AB and ZR-PO-HF specimens, bond strength was highest in the CPB+Activator group (25.8 MPa and 22.4 MPa, respectively). Bond strengths were significantly lower for ZR-AB specimens in the CON and PLB groups and for ZR-PO-AB specimens in the CON, CPB, and EOP groups. Combined application of a hydrophobic phosphate monomer (MDP) and silane coupling agent enhanced the long-term bond strength of indirect composite material to a zirconia coated with silica-based ceramics.

Batman-cracks. Observations and numerical simulations

NASA Astrophysics Data System (ADS)

Selvadurai, A. P. S.; Busschen, A. Ten; Ernst, L. J.

1991-05-01

To ensure mechanical strength of fiber reinforced plastics (FRP), good adhesion between fibers and the matrix is considered to be an essential requirement. An efficient test of fiber-matrix interface characterization is the fragmentation test which provides information about the interface slip mechanism. This test consists of the longitudinal loading of a single fiber which is embedded in a matrix specimen. At critical loads the fiber experiences fragmentation. This fragmentation will terminate depending upon the shear-slip strength of the fiber-matrix adhesion, which is inversely proportional to average fragment lengths. Depending upon interface strength characteristics either bond or slip matrix fracture can occur at the onset of fiber fracture. Certain particular features of matrix fracture are observed at the locations of fiber fracture in situations where there is sufficient interface bond strength. These refer to the development of fractures with a complex surface topography. The experimental procedure involved in the fragmentation tests is discussed and the boundary element technique to examine the development of multiple matrix fractures at the fiber fracture locations is examined. The mechanics of matrix fracture is examined. When bond integrity is maintained, a fiber fracture results in a matrix fracture. The matrix fracture topography in a fragmentation test is complex; however, simplified conoidal fracture patterns can be used to investigate the crack extension phenomena. Via a mixed-mode fracture criterion, the generation of a conoidal fracture pattern in the matrix is investigated. The numerical results compare favorably with observed experimental data derived from tests conducted on fragmentation test specimens consisting of a single glass fiber which is embedded in a polyester matrix.

Effect of Quaternary Ammonium Salt on Shear Bond Strength of Orthodontic Brackets to Enamel

PubMed Central

Ghadirian, Hannaneh; Geramy, Allahyar; Najafi, Farhood; Heidari, Soolmaz

2017-01-01

Objectives: This study sought to assess the effect of quaternary ammonium salt (QAS) on shear bond strength of orthodontic brackets to enamel. Materials and Methods: In this in vitro experimental study, 0, 10, 20 and 30% concentrations of QAS were added to Transbond XT primer. Brackets were bonded to 60 premolar teeth using the afore-mentioned adhesive mixtures, and the shear bond strength of the four groups (n=15) was measured using a universal testing machine. After debonding, the adhesive remnant index (ARI) score was determined under a stereomicroscope. Data were analyzed using one-way ANOVA. Results: The mean and standard deviation of shear bond strength of the control and 10%, 20% and 30% groups were 23.54±6.31, 21.81±2.82, 20.83±8.35 and 22.91±5.66 MPa, respectively. No significant difference was noted in shear bond strength of the groups (P=0.83). Study groups were not different in terms of ARI scores (P=0.80). Conclusions: The results showed that addition of QAS to Transbond XT primer had no adverse effect on shear bond strength of orthodontic brackets. PMID:29167688

Effect of Instrumentation Techniques, Irrigant Solutions and Artificial accelerated Aging on Fiberglass Post Bond Strength to Intraradicular Dentin.

PubMed

Santana, Fernanda Ribeiro; Soares, Carlos José; Silva, Júlio Almeida; Alencar, Ana Helena Gonçalves; Renovato, Sara Rodrigues; Lopes, Lawrence Gonzaga; Estrela, Carlos

2015-07-01

To evaluate the effect of instrumentation techniques, irrigant solutions and specimen aging on fiberglass posts bond strength to intraradicular dentine. A total of 120 bovine teeth were prepared and randomized into control and experimental groups resulting from three study factors (instrumentation techniques, irrigant solutions, specimen aging). Posts were cemented with RelyX U100. Samples were submitted to push-out test and failure mode was evaluated under a confocal microscope. In specimens submitted to water artificial aging, nickel-titanium rotary instruments group presented higher bond strength values in apical third irrigated with NaOCl or chlorhexi-dine. Irrigation with NaOCl resulted in higher bond strength than ozonated water. Artificial aging resulted in significant bond strength increase. Adhesive cement-dentin failure was prevalent in all the groups. Root canal preparation with NiTi instruments associated with NaOCl irrigation and ethylenediaminetetra acetic acid (EDTA) increased bond strength of fiberglass posts cemented with self-adhesive resin cement to intraradicular dentine. Water artificial aging significantly increased post-Clinical significance: The understanding of factors that may influence the optimal bond between post-cement and cement-dentin are essential to the success of endodontically treated tooth restoration.

Bonding Effectiveness of Luting Composites to Different CAD/CAM Materials.

PubMed

Peumans, Marleen; Valjakova, Emilija Bajraktarova; De Munck, Jan; Mishevska, Cece Bajraktarova; Van Meerbeek, Bart

To evaluate the influence of different surface treatments of six novel CAD/CAM materials on the bonding effectiveness of two luting composites. Six different CAD/CAM materials were tested: four ceramics - Vita Mark II; IPS Empress CAD and IPS e.max CAD; Celtra Duo - one hybrid ceramic, Vita Enamic, and one composite CAD/CAM block, Lava Ultimate. A total of 60 blocks (10 per material) received various mechanical surface treatments: 1. 600-grit SiC paper; 2. sandblasting with 30-μm Al2O3; 3. tribochemical silica coating (CoJet). Subsequent chemical surface treatments involved either no further treatment (control), HF acid etching (HF), silanization (S, or HF acid etching followed by silanization (HF+S). Two specimens with the same surface treatment were bonded together using two dual-curing luting composites: Clearfil Esthetic Cement (self-etching) or Panavia SA Cement (self-adhesive). After 1 week of water storage, the microtensile bond strength of the sectioned microspecimens was measured and the failure mode was evaluated. The bonding performance of the six CAD/CAM materials was significantly influenced by surface treatment (linear mixed models, p < 0.05). The luting cement had a significant influence on bond strength for Celtra Duo and Lava Ultimate (linear mixed models, p < 0.05). Mechanical surface treatment significantly influenced the bond strength for Celtra Duo (p = 0.0117), IPS e.max CAD (p = 0.0115), and Lava Ultimate (p < 0.0001). Different chemical surface treatments resulted in the highest bond strengths for the six CAD/CAM materials: Vita Mark II and IPS Empress CAD: S, HF+S; Celtra Duo: HF, HF+S; IPS e.max CAD: HF+S; Vita Enamic: HF+S, S. For Lava Ultimate, the highest bond strengths were obtained with HF, S, HF+S. Failure analysis showed a relation between bond strength and failure type: more mixed failures were observed with higher bond strengths. Mainly adhesive failures were noticed if no further surface treatment was done. The percentage of adhesive failures was higher for CAD/CAM materials with higher flexural strength (Celtra Duo, IPS e.max CAD, and Lava Ultimate). The bond strength of luting composites to novel CAD/CAM materials is influenced by surface treatment. For each luting composite, an adhesive cementation protocol can be specified in order to obtain the highest bond to the individual CAD/CAM materials.

Hot Roll Bonding of Aluminum to Twin-Roll Cast (TRC) Magnesium and Its Subsequent Deformation Behavior

NASA Astrophysics Data System (ADS)

Saleh, H.; Schmidtchen, M.; Kawalla, R.

2018-02-01

In an experiment in which twin-roll cast AZ31 magnesium alloy and commercial purity aluminum (AA 1050) sheets were bonded by hot rolling as Al/Mg/Al laminate composites, it was found that increasing the preheating temperatures up to 400 °C enhances the bonding strength of composites. Further increases in the preheating temperatures accelerate the magnesium oxide growth and thus reduce the bonding strength. The influence of the reduction ratio on the bonding properties was also studied, whereby it was observed that increasing the rolling reduction led to an increase in the bonding strength. The experimental results show that the optimum bonding strength can be obtained at rolling temperatures of 375-400 °C with a 50-60% reduction in thickness. On the other hand, the subsequent deformation behavior of composite was assessed using plane strain compression and deep drawing tests. We demonstrate that the composites produced using the optimum roll bonding conditions exhibited sufficient bonding during subsequent deformation and did not reveal any debonding at the bonding interface.

Influence of different methods of cleaning custom bases on the shear bond strength of indirectly bonded brackets.

PubMed

Kanashiro, Lylian K; Robles-Ruíz, Julissa J; Ciamponi, Ana L; Medeiros, Igor S; Tortamano, André; Paiva, João B

2014-09-01

To determine the influence on shear bond strength and bond failure location of four cleaning methods for orthodontic bracket custom bases. In vitro laboratory study. Eighty bovine teeth were divided at random into four groups. The bracket custom bases were cleaned with different methods: group 1 with methyl methacrylate monomer, group 2 with acetone, group 3 with 50 μm aluminium oxide particles and group 4 with detergent. The brackets were indirectly bonded onto the teeth with the Sondhi Rapid-Set self-curing adhesive. The maximum required shear bond strength to debond the brackets was recorded. The bond failure location was evaluated using the Adhesive Remnant Index (ARI). One-way analysis of variance (ANOVA) analysis (P<0·05) was used to detect significant differences in the bond strength. Kaplan-Meier survival plots and log-rank test were done to compare the survival distribution between the groups. The Kruskal-Wallis test (P<0·05) was used to evaluate the differences in the ARI scores. The mean bond strengths in groups 1, 2, 3 and 4 were 23·7±5·0, 25·3±5·1, 25·6±3·7 and 25·7±4·2 MPa, respectively. There were no significant statistically differences in either the bond strength or the ARI score between the groups. The four custom base-cleaning methods presented the same efficiencies on indirect bond of the brackets; thus, practitioners can choose the method that works best for them. © 2014 British Orthodontic Society.

Comparison of the bond strength of stainless steel orthodontic brackets bonded to crown porcelains.

PubMed

Chay, Siew Han; Wattanapayungkul, Pranee; Yap, Adrian U Jin; Loh, Poey Ling; Chung, Sew Meng

2005-05-01

The bond strengths and mode of failure of stainless steel orthodontic brackets bonded to the newer all-ceramic crown systems has not been fully investigated. To compare the shear-peel bond strengths and modes of failure of stainless steel Begg orthodontic brackets bonded to all-ceramic crown systems (Finesse, Empress II) and a conventional feldsphatic crown porcelain (Vita Omega 900). Fifteen flat-surface discs of three crown porcelains (Finesse, Vita Omega 900, Empress II) were made and mounted in acrylic moulds. The discs were pumiced, etched with phosphoric acid, primed with silane, and a flat stainless steel Begg bracket bonded to each disc with a chemical cure composite resin (Unite Bond). The discs were stored for one week in water and debonded with a sheer-peel load in an Instron uniaxial testing system with a crosshead speed of 0.5 mm/min. The composite remnants on the ceramic surfaces were classified using the Adhesive Remnant Index (ARI). The bond strength of Finesse (15.03 +/- 1.90 MPa) was significantly greater (p < 0.001) than Vita Omega 900 11.51 +/- 2.35 MPa) and Empress II (11.12 +/- 1.78 MPa). There were no significant differences among the ARI scores. The mode of failure was a mixture of adhesive and cohesive failure. The results indicate that the bond strengths of stainless steel orthodontic brackets bonded to Finesse and Empress II porcelains are clinically acceptable.

Microstructure and Mechanical Properties of Reaction-Formed Silicon Carbide (RFSC) Ceramics

NASA Technical Reports Server (NTRS)

Singh, M.; Behrendt, D. R.

1994-01-01

The microstructure and mechanical properties of reaction-formed silicon carbide (RFSC) ceramics fabricated by silicon infiltration of porous carbon preforms are discussed. The morphological characterization of the carbon preforms indicates a very narrow pore size distribution. Measurements of the preform density by physical methods and by mercury porosimetry agree very well and indicate that virtually all of the porosity in the preforms is open to infiltrating liquids. The average room temperature flexural strength of the RFSC material with approximately 8 at.% free silicon is 369 +/- 28 MPa (53.5 +/- 4 ksi). The Weibull strength distribution data give a characteristic strength value of 381 MPa (55 ksi) and a Weibull modulus of 14.3. The residual silicon content is lower and the strengths are superior to those of most commercially available reaction-bonded silicon carbide materials.

Evaluation of bond strength of various epoxy resin based sealers in oval shaped root canals.

PubMed

Cakici, Fatih; Cakici, Elif Bahar; Ceyhanli, Kadir Tolga; Celik, Ersan; Kucukekenci, Funda Fundaoglu; Gunseren, Arif Onur

2016-09-30

The aim of this study was to evaluate the bond strength of AH plus, Acroseal, and Adseal to the root canal dentin. A total of 36 single-rooted, mandibular premolar teeth were used. Root canal shaping procedures were performed with ProTaper rotary instruments (Dentsply Maillefer) up to size F4. The prepared samples were then randomly assembled into 3 groups (n = 12). For each group, an ultrasonic tip (size 15, 0.02 taper) which was also coated with an epoxy resin based sealer and placed 2 mm shorter than the working length. The sealer was then activated for 10 s. A push-out test was used to measure the bond strength between the root canal dentine and the sealer. Kruskal-Wallis test to evaluate the push-out bond strength of epoxy based sealer (P = 0.05). The failure mode data were statistically analyzed using Pearson's chi square test (P = 0.05). Kruskal-Wallis test indicated that there were no statistically significant difference among the push out bond strength values of 3 mm (p = 0.123) and 6 mm (P = 0.057) for groups, there was statistically significant difference push out bond strength value of 9 mm (P = 0.032). Pearson's chi square test showed statistically significant differences for the failure types among the groups. Various epoxy resin based sealers activated ultrasonically showed similar bond strength in oval shaped root canals. Apical sections for all groups have higher push out bond strength values than middle and coronal sections.

Shear Bond Strength of Self-etching Adhesives to Cavities Prepared by Diamond Bur or Er,Cr:YSGG Laser and Effect of Prior Acid Etching.

PubMed

Jhingan, Pulkit; Sachdev, Vinod; Sandhu, Meera; Sharma, Karan

2015-12-01

To compare and evaluate shear bond strength of self-etching adhesives bonded to cavities prepared by diamond bur or Er,Cr:YSGG laser and the effect of prior acid etching on shear bond strength. Ninety-six caries-free human premolars were selected and divided into 2 groups depending on mode of cavity preparation (48 teeth each). Cavities were prepared with Er,Cr:YSGG laser in group 1 and diamond burs in an air-turbine handpiece in group 2. Groups 1 and 2 were further subdivided into three subgroups of 8 teeth each, which were bonded with sixth- or seventh-generation adhesives with or without prior acid etching, followed by restoration of all samples with APX Flow. These samples were subjected to shear bond strength testing. In addition, the surface morphology of 24 samples each from groups 1 and 2 was evaluated using SEM. Data were analyzed using the Shapiro-Wilk test, one- and two-way ANOVA, the t-test, and the least significant difference test, which showed that the data were normally distributed (p > 0.05). The shear bond strength of adhesives in cavities prepared by Er,Cr:YSGG laser was significantly higher than in diamond bur-prepared cavities (p < 0.05). SEM analysis showed a smear-layer-free anfractuous surface on laser-ablated teeth, in contrast to conventional bur-prepared teeth. The Er,Cr:YSGG laser-ablated surface proved to be more receptive for adhesion than those prepared by diamond bur irrespective of the bonding agent used. Seventh-generation adhesives yielded higher shear bond strength than did sixth-generation adhesives. Prior acid etching decreased the shear bond strength of self-etching adhesives.

Influence of hydrophilic pre-treatment on resin bonding to zirconia ceramics.

PubMed

Noro, Akio; Kameyama, Atsushi; Haruyama, Akiko; Takahashi, Toshiyuki

2015-01-01

Atmospheric plasma or ultraviolet (UV) treatment alters the surface characteristics of tetragonal zirconia polycrystal (TZP), increasing its hydrophilicity by reducing the contact angle against water to zero. This suggests that such treatment would increase the wettability of bonding resin. The purpose of this study was to determine how increasing the hydrophilicity of TZP through plasma irradiation, UV treatment, or application of ceramic primer affected initial bonding with resin composites. Here, the effect of each pre-treatment on the hydrophilicity of TZP surfaces was determined by evaluating change in shear bond strength. Plasma irradiation, UV, or ceramic primer pre-treatment showed no significant effect on bonding strength between TZP surfaces and resin composites. In addition, alumina blasting yielded no significant increase in bond strength. Plasma irradiation, UV treatment, or ceramic primer pre-treatment did not lead to significant increase in bond strength between TZP and resin composites.

Effect of smear layer thickness and pH of self-adhesive resin cements on the shear bond strength to dentin.

PubMed

Ebrahimi Chaharom, Mohammad Esmaeel; Ajami, Amir Ahmad; Bahari, Mahmoud; Rezazadeh, Haleh

2017-01-01

There are concerns in relation to the bonding efficacy of self-adhesive resin cements to dentin covered with the smear layer. This study aims to evaluate the effect of smear layer thickness and different pH values of self-adhesive resin cements on the shear bond strength to dentin. The dentin on the buccal and lingual surfaces of 48 sound human premolars were abraded with 60- and 600-grit silicon carbide papers to achieve thick and thin smear layers, respectively. The samples were divided into three groups (n = 16) based on the cement pH: Rely-X Unicem (RXU) (pH < 2); Clearfil SA Luting (CSL) (pH = 3); and Speed CEM (SPC) (pH = 4.5). In each group, composite resin blocks were bonded to the buccal and lingual surfaces. After 24 h, the shear bond strength values were measured in MPa, and the failure modes were evaluated under a stereomicroscope. Data were analyzed with two-way ANOVA and post hoc least significant difference tests (P < 0.05). Cement pH had a significant effect on the shear bond strength (P = 0.02); however, the smear layer thickness had no significant effect on the shear bond strength (P > 0.05). The cumulative effect of these variables was not significant, either (P = 0.11). The shear bond strengths of SPC and CSL self-adhesive resin cements were similar and significantly lower than that of RXU. The smear layer thickness was not a determining factor for the shear bond strength value of self-adhesive resin cements.

A molecular scale perspective: Monte Carlo simulation for rupturing of ultra thin polymer film melts

NASA Astrophysics Data System (ADS)

Singh, Satya Pal

2017-04-01

Monte Carlo simulation has been performed to study the rupturing process of thin polymer film under strong confinement. The change in mean square displacement; pair correlation function; density distribution; average bond length and microscopic viscosity are sampled by varying the molecular interaction parameters such as the strength and the equilibrium positions of the bonding, non-bonding potentials and the sizes of the beads. The variation in mean square angular displacement χθ = [ < Δθ2 > - < Δθ>2 ] fits very well to a function of type y (t) = A + B *e-t/τ. This may help to study the viscous properties of the films and its dependence on different parameters. The ultra thin film annealed at high temperature gets ruptured and holes are created in the film mimicking spinodal dewetting. The pair correlation function and density profile reveal rich information about the equilibrium structure of the film. The strength and equilibrium bond length of finite extensible non-linear elastic potential (FENE) and non-bonding Morse potential have clear impact on microscopic rupturing of the film. The beads show Rouse or repetition motion forming rim like structures near the holes created inside the film. The higher order interaction as dipole-quadrupole may get prominence under strong confinement. The enhanced excluded volume interaction under strong confinement may overlap with the molecular dispersion forces. It can work to reorganize the molecules at the bottom of the scale and can imprint its signature in complex patterns evolved.

Rubbing time and bonding performance of one-step adhesives to primary enamel and dentin

PubMed Central

Botelho, Maria Paula Jacobucci; Isolan, Cristina Pereira; Schwantz, Júlia Kaster; Lopes, Murilo Baena; de Moraes, Rafael Ratto

2017-01-01

Abstract Objectives: This study investigated whether increasing the concentration of acidic monomers in one-step adhesives would allow reducing their application time without interfering with the bonding ability to primary enamel and dentin. Material and methods: Experimental one-step self-etch adhesives were formulated with 5 wt% (AD5), 20 wt% (AD20), or 35 wt% (AD35) acidic monomer. The adhesives were applied using rubbing motion for 5, 10, or 20 s. Bond strengths to primary enamel and dentin were tested under shear stress. A commercial etch-and-rinse adhesive (Single Bond 2; 3M ESPE) served as reference. Scanning electron microscopy was used to observe the morphology of bonded interfaces. Data were analysed at p<0.05. Results: In enamel, AD35 had higher bond strength when rubbed for at least 10 s, while application for 5 s generated lower bond strength. In dentin, increased acidic monomer improved bonding only for 20 s rubbing time. The etch-and-rinse adhesive yielded higher bond strength to enamel and similar bonding to dentin as compared with the self-etch adhesives. The adhesive layer was thicker and more irregular for the etch-and-rinse material, with no appreciable differences among the self-etch systems. Conclusion: Overall, increasing the acidic monomer concentration only led to an increase in bond strength to enamel when the rubbing time was at least 10 s. In dentin, despite the increase in bond strength with longer rubbing times, the results favoured the experimental adhesives compared to the conventional adhesive. Reduced rubbing time of self-etch adhesives should be avoided in the clinical setup. PMID:29069150

[Bonding strength of resin and tooth enamel after teeth bleaching with cold plasma].

PubMed

Zhu, Meng-meng; Wang, Guo-min; Sun, Ke; Li, Ying-long; Pan, Jie

2016-02-18

To investigate the immediate bond strength and surface structure of resin and the tooth enamel which treated by cold plasma. In the study, 40 bovine incisors were divided into two equal parts. In this sense, all enamel adhesive samples were prepared and then randomly divided into 4 groups (n =20). group 1: acid + single bond 2+resin composite (control group); group 2:beyond bleaching+ acid+single bond 2+resin composite; group 3: treated by cold plasma for 5 minutes+ acid+single bond 2+resin composite; group 4: treated by cold plasma for 5 minutes+single bond 2+resin composite. Single bond 2 bonding system and Filtek Z250 resin were used in this experiment. The shear bond strength was tested by universal testing machine. The surface of the enamel in different processes was observed by scanning electron microscope (SEM). Statistical analyses by the single factor analysis of variance and multiple pairwise comparisons were performed with SPSS 17.0 . The shear bond strength of group 4 (8.60 MPa) was significantly lower than that of the other three groups (P<0.05). The shear bond strength of group 2 (17.89 MPa) was higher than that of group 4, but lower than group 1 and group 3 (P<0.05).There was no significant difference between group 1 (34.82 MPa) and group 3 (34.69 MPa). Scanning electron microscope indicated that the enamel treated by cold plasma had slight molten form, which was different from etched enamel surface.The fractured surface of group 3 was mix fracture, which was similar to the control group (group 1). Compared with the conventional clinic bleaching, immediate bond strength of resin-enamel that treated by cold plasma has not been affected.

Effectiveness and stability of silane coupling agent incorporated in 'universal' adhesives.

PubMed

Yoshihara, Kumiko; Nagaoka, Noriyuki; Sonoda, Akinari; Maruo, Yukinori; Makita, Yoji; Okihara, Takumi; Irie, Masao; Yoshida, Yasuhiro; Van Meerbeek, Bart

2016-10-01

For bonding indirect restorations, some 'universal' adhesives incorporate a silane coupling agent to chemically bond to glass-rich ceramics so that a separate ceramic primer is claimed to be no longer needed. With this work, we investigated the effectiveness/stability of the silane coupling function of the silanecontaining experimentally prepared adhesives and Scotchbond Universal (3MESPE). Experimental adhesives consisted of Scotchbond Universal and the silane-free Clearfil S3 ND Quick (Kuraray Noritake) mixed with Clearfil Porcelain Bond Activator (Kuraray Noritake) and the two adhesives to which γ-methacryloxypropyltrimethoxysilane (γ-MPTS) was added. Shear bond strength was measured onto silica-glass plates; the adhesive formulations were analyzed using fourier transform infrared spectroscopy (FTIR) and 13C nuclear magnetic resonance (NMR). In addition, shear bond strength onto CAD-CAM composite blocks was measured without and after thermo-cycling ageing. A significantly higher bond strength was recorded when Clearfil Porcelain Bond Activator was freshly mixed with the adhesive. Likewise, the experimental adhesives, to which γ-MPTS was added, revealed a significantly higher bond strength, but only when the adhesive was applied immediately after mixing; delayed application resulted in a significantly lower bond strength. FTIR and (13)C NMR revealed hydrolysis and dehydration condensation to progress with the time after γ-MPTS was mixed with the two adhesives. After thermo-cycling, the bond strength onto CAD-CAM composite blocks remained stable only for the two adhesives with which Clearfil Porcelain Bond Activator was mixed. Only the silane coupling effect of freshly prepared silanecontaining adhesives was effective. Clinically, the use of a separate silane primer or silane freshly mixed with the adhesive remains recommended to bond glass-rich ceramics. Copyright © 2016 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Shore hardness and tensile bond strength of long-term soft denture lining materials.

PubMed

Kim, Bong-Jun; Yang, Hong-So; Chun, Min-Geoung; Park, Yeong-Joon

2014-11-01

Reduced softness and separation from the denture base are the most significant problems of long-term soft lining materials. The purpose of this study was to evaluate the durometer Shore A hardness and tensile bond strength of long-term soft denture lining materials and to investigate the correlation between these 2 properties. A group of 7 soft lining materials, 6 silicone based (Dentusil, GC Reline Soft, GC Reline Ultrasoft, Mucopren Soft, Mucosoft, Sofreliner Tough) and 1 acrylic resin based (Durabase), were evaluated for durometer Shore A hardness and tensile bond strength to heat-polymerized denture base resin (Lucitone 199). A specially designed split mold and loading assembly with a swivel connector were used for the durometer Shore A hardness test and tensile bond strength test to improve accuracy and facilitate measurement. Three specimens of each product were stored in a 37°C water bath, and durometer Shore A hardness tests were carried out after 24 hours and 28 days. A tensile bond strength test was carried out for 10 specimens of each product, which were stored in a 37°C water bath for 24 hours before the test. Repeated-measures ANOVA, the Kruskal-Wallis and Duncan multiple range tests, and the Spearman correlation were used for statistical analyses. The repeated-measures ANOVA found significant durometer Shore A hardness differences for the materials (P<.001) and the interaction effect (aging×materials) (P<.001). GC Reline Ultrasoft showed the lowest mean durometer Shore A hardness (21.30 ±0.29 for 24 hours, 34.73 ±0.47 for 28 days), and GC Reline Soft showed the highest mean durometer Shore A hardness (50.13 ±0.48 for 24 hours, 57.20 ±0.28 for 28 days). The Kruskal-Wallis test found a significant difference in the mean tensile bond strength values (P<.001). GC Reline Ultrasoft (0.82 ±0.32 MPa) and Mucopren Soft (0.96 ±0.46 MPa) had a significantly lower mean tensile bond strength (P<.05). GC Reline Soft had the highest mean tensile bond strength (2.99 ±0.43 MPa) (P<.05), and acrylic resin-based Durabase showed a significantly different tensile bond strength (1.32 ±0.16 MPa), except for Mucopren Soft, among the materials (P<.05). The tensile bond strength and Shore A hardness showed a statistically insignificant moderate positive correlation (r=0.571, P=.180 for Shore A hardness 24 hours versus tensile bond strength; r=0.607, P=.148 for Shore A hardness 28 days versus tensile bond strength). Within the limitations of this study, significant differences were found in durometer Shore A hardness (with aging time) and tensile bond strength among the materials. Adhesive failure was moderately correlated with durometer Shore A hardness, especially after 28 days, but was not significant. Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Push-out bond strengths of two fiber post types bonded with different dentin bonding agents.

PubMed

Topcu, Fulya Toksoy; Erdemir, Ugur; Sahinkesen, Gunes; Mumcu, Emre; Yildiz, Esra; Uslan, Ibrahim

2010-05-01

The aim of this study was to evaluate the regional push-out bond strengths for two fiber-reinforced post types using three different dentin bonding agents. Sixty single-rooted extracted human first premolar teeth were sectioned below the cemento-enamel junction, and the roots were endodontically treated. Following standardized post space preparations, the roots were divided into two fiber-post groups (Glassix and Carbopost), and further divided into three subgroups of 10 specimens each for the bonding systems self-etching dentin bonding agents (Clearfil SE Bond and Optibond all-in-one), and total-etching dentin bonding agent (XP Bond). A dual-cure resin luting cement (Maxcem) was then placed in the post spaces and posts were then seated into the root canals polymerized through the cervical portion. The roots were then cut into 3-mm thick sections. Push-out tests were performed at a crosshead speed of 0.5 mm/min. The data were analyzed with multivariate ANOVA (alpha = 0.05). The morphology of interface between different dentin bonding agents from the cervical sections were analyzed with SEM. Glass fiber-reinforced posts demonstrated significantly higher push-out bond strengths than carbon fiber-reinforced posts (p < 0.001). Bond strength values decreased significantly from the cervical to the apical root canal regions (p < 0.001). Self-etching dentin adhesive Clearfil SE Bond and total-etching dentin adhesive XP Bond demonstrated similar bond strengths values and this was significantly higher compared with the Optibond all-in-one in cervical root canal region. In conclusion, in all root segments, the glass fiber-reinforced posts provided significantly increased post retention than the carbon fiber-reinforced posts, regardless of the adhesive used. (c) 2010 Wiley Periodicals, Inc.

Two-year water degradation of self-etching adhesives bonded to bur ground enamel.

PubMed

Abdalla, Ali I; Feilzer, Albert J

2009-01-01

To evaluate the effect of water storage on the microshear bond strength to ground enamel of three "all-in-one" self-etch adhesives: Futurabond DC, Clearfil S Tri Bond and Hybrid bond; a self-etching primer; Clearfil SE Bond and an etch-and-rinse adhesive system, Admira Bond. Sixty human molars were used. The root of each tooth was removed and the crown was sectioned into two halves. The convex enamel surfaces were reduced by polishing on silicon paper to prepare a flat surface that was roughened with a parallel-sided diamond bur with abundant water for five seconds. The bonding systems were applied on this surface. Prior to adhesive curing, a hollow cylinder (2.0 mm in height/0.75 mm in internal diameter) was placed on the treated surfaces and cured. A resin composite was then inserted into the tube and cured. For each adhesive, two procedures were carried out: A--the specimens were kept in water for 24 hours, then the tube was removed and the microshear bond strength was determined in a universal testing machine at a crosshead speed of 0.5 mm/minute; B--the specimens were stored in water for two-years before microshear testing. The fractured surface of the bonded specimens after each test procedure was examined by SEM. For the 24-hour control, there was no significant difference in bond strength between the tested adhesives. After two years of water storage, the bond strength of Admira Bond, Clearfil SE Bond and Futurabond DC decreased, but the reduction was not significantly different from that of 24 hours. For Clearfil S Tri Bond and Hybrid Bond, the bond strengths were significantly reduced compared to their 24-hour results.

Effect of air-blowing duration on the bond strength of current one-step adhesives to dentin.

PubMed

Fu, Jiale; Saikaew, Pipop; Kawano, Shimpei; Carvalho, Ricardo M; Hannig, Matthias; Sano, Hidehiko; Selimovic, Denis

2017-08-01

To evaluate the influence of different air-blowing durations on the micro-tensile bond strength (μTBS) of five current one-step adhesive systems to dentin. One hundred and five caries-free human molars and five current one-step adhesive systems were used: ABU (All Bond Universal, Bisco, Inc.), CUB (CLEARFIL™ Universal Bond, Kuraray), GPB (G-Premio BOND, GC), OBA (OptiBond All-in-one, Kerr) and SBU (Scotchbond Universal, 3M ESPE). The adhesives were applied to 600 SiC paper-flat dentin surfaces according to each manufacturer's instructions and were air-dried with standard, oil-free air pressure of 0.25MPa for either 0s, 5s, 15s or 30s before light-curing. Bond strength to dentin was determined by using μTBS test after 24h of water storage. The fracture pattern on the dentin surface was analyzed by SEM. The resin-dentin interface of untested specimens was visualized by panoramic SEM image. Data from μTBS were analyzed using two-way ANOVA (adhesive vs. air-blowing time), and Games-Howell (a=0.05). Two-way ANOVA revealed a significant effect of materials (p=0.000) and air-blowing time (p=0.000) on bond strength to dentin. The interaction between factors was also significantly different (p=0.000). Maximum bond strength for each system were recorded, OBA/15s (76.34±19.15MPa), SBU/15s (75.18±12.83MPa), CUB/15s (68.23±16.36MPa), GPB/30s (55.82±12.99MPa) and ABU/15s (44.75±8.95MPa). The maximum bond strength of OBA and SUB were significantly higher than that of GPB and ABU (p<0.05). The bond strength of the current one-step adhesive systems is material-dependent (p=0.000), and was influenced by air-blowing duration (p=0.000). For the current one-step adhesive systems, higher bond strengths could be achieved with prolonged air-blowing duration between 15-30s. Copyright © 2017 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Bonding of acrylic denture teeth to MMA/PMMA and light-curing denture base materials: the role of conditioning liquids.

PubMed

Palitsch, Anne; Hannig, Matthias; Ferger, Paul; Balkenhol, Markus

2012-03-01

The connection between resin denture teeth and the denture base is essential for the integrity of partial and full dentures. The aim of the present study was to analyse the bond strength of acrylic denture teeth to two light curing denture base materials compared to the gold-standard (MMA/PMMA) using different conditioning liquids. The ridge laps of 220 identical denture teeth were ground and pre-treated using different conditioning liquids (MMA, an experimental conditioning liquid as well as the two commercially available liquids Palabond and Versyo.bond). The denture base materials (PalaXpress, Versyo.com, Eclipse) were applied using a split mould to obtain tensile bond strength specimens of identical shape. Ten specimens per test group were either stored in water for 24h or thermocycled (5000×, 5-55°C) prior to tensile bond strength testing (cross-head speed 10mm/min). Data was subjected to parametric statistics (α=0.05). The three-way ANOVA revealed a significant influence of the material, pre-treatment as well as the storage. PalaXpress showed the highest bond strength (24.3MPa) of all materials tested after TC, whereas the use of MMA led to the most constant results. Lower values were recorded for Versyo.com (17.5MPa) and Eclipse (10.4MPa) bonded with Versyo.bond. The results indicate that MMA/PMMA based denture base resins provide reliable and durable bond strength to acrylic denture teeth. Using light-curing denture base materials requires the application of appropriate conditioning liquids to obtain acceptable bond strength. The use of MMA affects bond strength to light-curing denture base materials. The pre-treatment of denture teeth is critical regarding their bond-strength to denture base materials and in turn for the integrity of removable full and partial dentures. Light-curing denture base resins are more sensitive to the correct tooth pre-treatment compared to conventional MMA/PMMA materials, requiring specific conditioning liquids. Copyright © 2011 Elsevier Ltd. All rights reserved.

Effect of Reduced Phosphoric Acid Pre-etching Times 
on Enamel Surface Characteristics and Shear Fatigue Strength Using Universal Adhesives.

PubMed

Tsujimoto, Akimasa; Fischer, Nicholas; Barkmeier, Wayne; Baruth, Andrew; Takamizawa, Toshiki; Latta, Mark; Miyazaki, Masashi

2017-01-01

To examine the effect of reduced phosphoric acid pre-etching times on enamel fatigue bond strength of universal adhesives and surface characteristics by using atomic force microscopy (AFM). Three universal adhesives were used in this study (Clearfil Universal Bond [C], G-Premio Bond [GP], Scotchbond Universal Adhesive [SU]). Four pre-etching groups were employed: enamel pre-etched with phosphoric acid and immediately rinsed with an air-water spray, and enamel pre-etched with phosphoric acid for 5, 10, or 15 s. Ground enamel was used as the control group. For the initial bond strength test, 15 specimens per etching group for each adhesive were used. For the shear fatigue test, 20 specimens per etching group for each adhesive were loaded using a sine wave at a frequency of 20 Hz for 50,000 cycles or until failure occurred. Initial shear bond strengths and fatigue shear strengths of composite adhesively bonded to ground and pre-etched enamel were determined. AFM observations of ground and pre-etched enamel were also conducted, and surface roughness as well as surface area were evaluated. The initial shear bond strengths and fatigue shear strengths of the universal adhesives in the pre-etched groups were significantly higher than those of the control group, and were not influenced by the pre-etching time. Significantly higher surface roughness and surface area of enamel surfaces in pre-etched groups were observed compared with those in the control group. While the surface area was not significantly influenced by etching time, surface roughness of the enamel surfaces in the pre-etched groups significantly increased with pre-etching time. The results of this in vitro study suggest that reduced phosphoric acid pre-etching times do not impair the fatigue bond strength of universal adhesives. Although fatigue bond strength and surface area were not influenced by phosphoric-acid etching times, surface roughness increased with increasing etching time.

An insight into current concepts and techniques in resin bonding to high strength ceramics.

PubMed

Luthra, R; Kaur, P

2016-06-01

Reliable bonding between high strength ceramics and resin composite cement is difficult to achieve because of their chemical inertness and lack of silica content. The aim of this review was to assess the current literature describing methods for resin bonding to ceramics with high flexural strength such as glass-infiltrated alumina and zirconia, densely sintered alumina and yttria-partially stabilized tetragonal zirconia polycrystalline ceramic (Y-TZP) with respect to bond strength and bond durability. Suitable peer reviewed publications in the English language were identified through searches performed in PubMed, Google Search and handsearches. The keywords or phrases used were 'resin-ceramic bond', 'silane coupling agents', 'air particle abrasion', 'zirconia ceramic' and 'resin composite cements'. Studies from January 1989 to June 2015 were included. The literature demonstrated that there are multiple techniques available for surface treatments but bond strength testing under different investigations have produced conflicting results. Within the scope of this review, there is no evidence to support a universal technique of ceramic surface treatment for adhesive cementation. A combination of chemical and mechanical treatments might be the recommended solution. The hydrolytic stability of the resin ceramic bond should be enhanced. © 2016 Australian Dental Association.

Influence of dentinal regions on bond strengths of different adhesive systems.

PubMed

Ozer, F; Unlü, N; Sengun, A

2003-06-01

This in vitro study assessed comparatively the shear bond strengths of three composite resins, 3M Valux Plus (3MVP), Herculite (H), Clearfil AP-X (CAP-X), a polyacid modified composite resin Dyract (D), and a resin modified glass-ionomer materials Vitremer (V), to cervical and buccal dentine regions of extracted human molar teeth. Four different bonding systems, 3M ScotchBond Multipurpose (SB), Clearfil Liner Bond 2 (LB2), Opti Bond (OB), and Prime & Bond 2.1 (PB 2.1) were used with the manufacturer's respective composite and compomer materials. One hundred freshly extracted mandibular molar teeth were selected for this study. Flat buccal dentine surfaces were created on 50 teeth and cylindrical rods of the five materials were bonded to the dentine surfaces. For assessment of cervical bond strengths, the materials were bonded to mesial and distal enamel bordered occlusal dentinal surfaces of the remaining 50 teeth. The five groups of restorative procedures were applied as follows; Group 1: SB + 3MVP, Group 2: LB2 + CAP-X, Group 3: OB + H, Group 4: PB2.1 + D, Group 5: Vitremer primer (VP) VP + V. Each restorative procedure thus had 20 specimens (10 buccal + 10 cervical). After 24 h of water storage (37 degrees C), the specimens were tested on a Universal Testing machine in shear with a cross head speed of 0.5 mm min-1. The bond strength values were calculated in MPa and the results were evaluated statistically using Kruskal-Wallis one-way/anova and Mann-Whitney U-tests. It was found that the bond strengths of SB + 3MVP, LB2 + CAP-X and VP + V to buccal dentine surfaces were significantly stronger (P < 0.05) than those to the occluso-cervical dentine floors. When the bond strengths to the occluso-cervical dentine and buccal dentine surface were compared, there was no significant difference between the materials (P > 0.05). Vitremer was found the least successful adhesive material in terms of shear bond strength on both buccal and occluso-cervical dentine surfaces.

The bond of different post materials to a resin composite cement and a resin composite core material.

PubMed

Stewardson, D; Shortall, A; Marquis, P

2012-01-01

To investigate the bond of endodontic post materials, with and without grit blasting, to a resin composite cement and a core material using push-out bond strength tests. Fiber-reinforced composite (FRC) posts containing carbon (C) or glass (A) fiber and a steel (S) post were cemented into cylinders of polymerized restorative composite without surface treatment (as controls) and after grit blasting for 8, 16, and 32 seconds. Additional steel post samples were sputter-coated with gold before cementation to prevent chemical interaction with the cement. Cylindrical composite cores were bonded to other samples. After sectioning into discs, bond strengths were determined using push-out testing. Profilometry and electron microscopy were used to assess the effect of grit blasting on surface topography. Mean (standard deviation) bond strength values (MPa) for untreated posts to resin cement were 8.41 (2.80) for C, 9.61(1.88) for A, and 19.90 (3.61) for S. Prolonged grit blasting increased bond strength for FRC posts but produced only a minimal increase for S. After 32 seconds, mean values were 20.65 (4.91) for C, 20.41 (2.93) for A, and 22.97 (2.87) for S. Gold-coated steel samples produced the lowest bond strength value, 7.84 (1.40). Mean bond strengths for untreated posts bonded to composite cores were 6.19 (0.95) for C, 13.22 (1.61) for A, and 8.82 (1.18) for S, and after 32 seconds of grit blasting the values were 17.30 (2.02) for C, 26.47 (3.09) for A, and 20.61 (2.67) for S. FRC materials recorded higher roughness values before and after grit blasting than S. With prolonged grit blasting, roughness increased for A and C, but not for S. There was no evidence of significant bonding to untreated FRC posts, but significant bonding occurred between untreated steel posts and the resin cement. Increases in the roughness of FRC samples were material dependent and roughening significantly increased bond strength values (p<0.05). Surface roughening of the tested FRC posts is required for effective bonding.

Effects of etching time on enamel bond strengths.

PubMed

Triolo, P T; Swift, E J; Mudgil, A; Levine, A

1993-12-01

This study evaluated the effects of etching time on bond strengths of composite to enamel. Proximal surfaces of extracted molars were etched with either a conventional etchant (35% phosphoric acid) or one of two dentin/enamel conditioners, 10% maleic acid (Scotchbond Multi-Purpose Etchant), or a solution of oxalic acid, aluminum nitrate, and glycine (Gluma 1 & 2 Conditioner). Each agent was applied for 15, 30, or 60 seconds. Specimens etched with 35% phosphoric acid had the highest mean bond strengths at each etching time. At the manufacturer's recommended application times, the other two agents gave significantly lower shear bond strengths than phosphoric acid.

New Fukui, dual and hyper-dual kernels as bond reactivity descriptors.

PubMed

Franco-Pérez, Marco; Polanco-Ramírez, Carlos-A; Ayers, Paul W; Gázquez, José L; Vela, Alberto

2017-06-21

We define three new linear response indices with promising applications for bond reactivity using the mathematical framework of τ-CRT (finite temperature chemical reactivity theory). The τ-Fukui kernel is defined as the ratio between the fluctuations of the average electron density at two different points in the space and the fluctuations in the average electron number and is designed to integrate to the finite-temperature definition of the electronic Fukui function. When this kernel is condensed, it can be interpreted as a site-reactivity descriptor of the boundary region between two atoms. The τ-dual kernel corresponds to the first order response of the Fukui kernel and is designed to integrate to the finite temperature definition of the dual descriptor; it indicates the ambiphilic reactivity of a specific bond and enriches the traditional dual descriptor by allowing one to distinguish between the electron-accepting and electron-donating processes. Finally, the τ-hyper dual kernel is defined as the second-order derivative of the Fukui kernel and is proposed as a measure of the strength of ambiphilic bonding interactions. Although these quantities have never been proposed, our results for the τ-Fukui kernel and for τ-dual kernel can be derived in zero-temperature formulation of the chemical reactivity theory with, among other things, the widely-used parabolic interpolation model.

Comparison of the metal-to-ceramic bond strengths of four noble alloys with press-on-metal and conventional porcelain layering techniques.

PubMed

Khmaj, Mofida R; Khmaj, Abdulfatah B; Brantley, William A; Johnston, William M; Dasgupta, Tridib

2014-11-01

New noble alloys for metal ceramic restorations introduced by manufacturers are generally lower-cost alternatives to traditional higher-gold alloys. Information about the metal-to-ceramic bond strength for these alloys, which is needed for rational clinical selection, is often lacking. The purpose of this study was to evaluate the bond strength of 4 recently introduced noble alloys by using 2 techniques for porcelain application. Aquarius Hard (high-gold: 86.1 gold, 8.5 platinum, 2.6 palladium, 1.4 indium; values in wt. %), Evolution Lite (reduced-gold: 40.3 gold, 39.3 palladium, 9.3 indium, 9.2 silver, 1.8 gallium), Callisto 75 Pd (palladium-silver containing gold: 75.2 palladium, 7.1 silver, 2.5 gold, 9.3 tin, 1.0 indium), and Aries, (conventional palladium-silver: 63.7 palladium, 26.0 silver, 7.0 tin, 1.8 gallium, 1.5 indium) were selected for bonding to leucite-containing veneering porcelains. Ten metal ceramic specimens that met dimensional requirements for International Organization for Standardization (ISO) Standard 9693 were prepared for each alloy by using conventional porcelain layering and press-on-metal methods. The 3-point bending test in ISO Standard 9693 was used to determine bond strength. Values were compared with 2-way ANOVA (maximum likelihood analysis, SAS Mixed Procedure) and the Tukey test (α=.05). Means (standard deviations) for bond strength with conventional porcelain layering were as follows: Aquarius Hard (50.7 ±5.5 MPa), Evolution Lite (40.2 ±3.3 MPa), Callisto 75 Pd (37.2 ±3.9 MPa), and Aries (34.0 ±4.9 MPa). For the press-on-metal technique, bond strength results were as follows: Aquarius Hard (33.7 ±11.5 MPa), Evolution Lite (34.9 ±4.5 MPa), Callisto 75 Pd (37.2 ±11.9 MPa), and Aries (30.7 ±10.8 MPa). From statistical analyses, the following 3 significant differences were found for metal-to-ceramic bond strength: the bond strength for Aquarius Hard was significantly higher for conventional porcelain layers compared with the press-on-metal technique; the bond strength for Aquarius Hard with conventional porcelain layers was significantly higher than the bond strengths for the other 3 alloys with conventional porcelain layers; and the bond strength for Aquarius Hard with conventional porcelain layers was significantly higher than the bond strength for Callisto 75 Pd with conventional porcelain layers and the other 3 alloys with the press-on-metal technique. For both conventional layering and press-on-metal techniques, all 4 noble alloys had a mean metal-to-ceramic bond strength that substantially exceeded the 25 MPa minimum in the ISO Standard 9693. The results for Aries support the manufacturer's recommendation not to use the press-on-metal technique for alloys that contain more than 10% silver. Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Assessing the effects of hydrogen peroxide bleaching agent on the shear bond strength of orthodontic brackets.

PubMed

Andrighetto, Augusto Ricardo; de Leão Withers, Eduardo Henrique; Grando, Karlos Giovani; Ambrosio, Aldrieli Regina; Shimizu, Roberto Hideo; Melo, Ana Cláudia

2016-01-01

Tooth bleaching is, today, one of the most widespread cosmetic treatments in dental practice,  so it is important to determine whether it can interfere with orthodontic bonding or not. The aim of this study was to assess the in vitro effects of 35% hydrogen peroxide bleaching agent on the shear bond strength of orthodontic brackets. Forty-five upper bicuspids were divided into three groups (n = 15). In the control Group (C), the brackets were bonded without previous bleaching treatment. Group 1 (G1) was treated with 35% hydrogen peroxide bleaching agent 24 h before bracket bonding. Group 2 was also bleached, and the brackets were bonded after 30 days. The shear bond strength of the brackets was measured using an EMIC machine, and the results were analyzed by ANOVA. There were no statistically significant differences between the three groups (P > 0.05), with Group C showing a mean bond strength of 9.72 ± 2.63 MPa, G1 of 8.09 ± 2.63 MPa, and G2 of 11.15 ± 4.42 MPa. It was possible to conclude that 35% hydrogen peroxide bleaching agent does not affect the shear strength of orthodontic brackets bonded 24 h and 30 days after bleaching.

Experimental and Theoretical Investigations on Bond Strength of GFRP Rebars in Normal and High Strength Concrete

NASA Astrophysics Data System (ADS)

Eswanth, P.; Dhinakaran, G.

2017-07-01

Bond behavior between GFRP bars and concrete is the most important parameter for constructing corrosion free structures by implementing the material. Serviceability of reinforced concrete structures are controlled by bond behavior. GFRP materials behave differently from reinforcing steel in terms of bond. They are of non-homogeneous and anisotropic. Due to this outstanding behavior, there is a difference in transfer of loads between GFRP bars and concrete which made it as an idealized choice of a material. In the present work, the bond strength of GFRP bars in normal and high strength concrete was studied. In total, 12 specimens containing 12 mm, 16 mm diameter rebars which were embedded in 150 mm x 150 mm x 150 mm cubes were investigated. The specimens were subjected to direct tension pull out test in accordance with IS 2770 part 1. The comparison of bond properties of GFRP rebar in normal and high strength concrete showed that pull out load of non-metallic rebar fell well within the range.

Bonding strength and durability of alkaline-treated titanium to veneering resin.

PubMed

Ban, Seiji; Kadokawa, Akihiko; Kanie, Takahito; Arikawa, Hiroyuki; Fujii, Koichi; Tanaka, Takuo

2004-09-01

The shear bonding strengths of a veneering resin to polished, sandblasted, and retention bead-cast commercially pure titanium (cpTi) plates with and without alkaline treatment were measured before and after thermal cycling. The bonding strengths to polished cpTi with and without alkaline treatment decreased remarkably with thermal cycling (p<0.01). The bonding strength to sandblasted cpTi with alkaline treatment at 5,000 thermal cycles showed no significant differences from those before thermal cycling (p>0.05), and those at 20,000 thermal cycles showed values which were quite small (p<0.01). On the other hand, there were no significant differences in the bonding strengths of veneering resin to retention bead-cast cpTi in all conditions (p>0.05). These results suggested that although alkaline treatment is a simple and effective surface modification technique for titanium improving adhesion to resin due to formation of tight-fine rutile particles, it does not provide sufficient bonding durability for long-period restorations.

Evaluation of the effect of three innovative recyling methods on the shear bond strength of stainless steel brackets-an in vitro study

PubMed Central

Kumar, Dilip; Palla, Aparna

2017-01-01

Background Orthodontists are commonly faced with the decision of what to do with debonded or inaccurately positioned brackets. An economical option to this dilemma is to recycle the brackets. Many recycling methods have been proposed, but the optimal bond strength of these recycled brackets needs further evaluation. Objectives: To evaluate and compare the effect of three recycling methods: (i) Sandblasting (ii) Sandblasting / direct flaming (iii) Sandblasting /direct flaming /acid bath solution on shear bond strength (SBS) of stainless steel brackets. Material and Methods Eighty human premolars were bonded with premolar stainless steel brackets as per manufacturer’s instructions. The teeth were divided into 4 groups (n=20): Recycling and initial debonding was not done in Control group (Group I). After initial bonding, the brackets in the rest of the three experimental groups were debonded and recycled by following methods: (i) Sandblasting (Group II) (ii) Sandblasting /direct flaming (Group III) (iii) Sandblasting /direct flaming /acid bath solution (Group IV). Further the recycled brackets were bonded. The specimens were then subjected to testing in a Universal machine. The evaluation of the variation of the shear bond strength (SBS) among test groups was done using one-way ANOVA test and inter-experimental group comparison was done by Newman-Keuls multiple post hoc procedure. Results Group I (8.6510±1.3943MPa) showed the highest bond strength followed by Group II (5.0185±0.9758MPa), Group IV (2.30±0.65MPa) and Group III (2.0455± 0.6196MPa). Statistically significant variations existed in the shear bond strength (SBS) in all groups analyzed except between Group III and Group IV. Conclusions The following conclusions were drawn from the study: 1. Shear bond strength of new brackets is significantly higher than the recycled brackets. 2. Brackets sandblasted with 90µm aluminium oxide particle air-abrasion showed significantly higher shear bond strength compared to direct flaming/sandblasting and direct flaming/sandblasting/acid bath solution. 3. Sandblasting with 90µm aluminium oxide particle air-abrasion is the simplest, most efficient and hence, the preferred method of recycling debonded brackets. Key words:Orthodontic bracket, recycling, shear bond strength. PMID:28469821

Comparative evaluation of tensile bond strength of a polyvinyl acetate-based resilient liner following various denture base surface pre-treatment methods and immersion in artificial salivary medium: An in vitro study.

PubMed

Philip, Jacob M; Ganapathy, Dhanraj M; Ariga, Padma

2012-07-01

This study was formulated to evaluate and estimate the influence of various denture base resin surface pre-treatments (chemical and mechanical and combinations) upon tensile bond strength between a poly vinyl acetate-based denture liner and a denture base resin. A universal testing machine was used for determining the bond strength of the liner to surface pre-treated acrylic resin blocks. The data was analyzed by one-way analysis of variance and the t-test (α =.05). This study infers that denture base surface pre-treatment can improve the adhesive tensile bond strength between the liner and denture base specimens. The results of this study infer that chemical, mechanical, and mechano-chemical pre-treatments will have different effects on the bond strength of the acrylic soft resilient liner to the denture base. Among the various methods of pre-treatment of denture base resins, it was inferred that the mechano-chemical pre-treatment method with air-borne particle abrasion followed by monomer application exhibited superior bond strength than other methods with the resilient liner. Hence, this method could be effectively used to improve bond strength between liner and denture base and thus could minimize delamination of liner from the denture base during function.

Bond strengths of custom cast and prefabricated posts luted with two cements.

PubMed

Aleisa, Khalil Ibrahim

2011-02-01

This in vitro study evaluated the bond strength of custom cast and prefabricated posts luted with resin or zinc phosphate cements into unobturated canals of extracted teeth. Forty-eight custom cast and prefabricated posts were placed into extracted single-rooted human teeth. Post-cavity preparation was 1.5 mm in diameter and 10 mm in depth. Specimens were randomly divided into 4 groups of 12 each. Two of the groups were then luted with resin cement, while the other two groups were luted with zinc phosphate cement. A pull-out bond strength evaluation was performed using a universal testing machine. The Kolmogorov-Smirnov test was used to prove normal distribution. Data were statistically analyzed using two-way ANOVA and the Student t test (alpha = .05). For both luting agents, the prefabricated posts group exhibited significantly less bond strength than the custom cast posts group (P = .0001). There were statistically significant differences in mean bond strength for the prefabricated posts group luted with resin cement vs the group cemented with zinc phosphate cement (P = .002). There was no significant difference between the mean bond strength values of custom cast posts luted with resin cement or zinc phosphate cement. Custom cast posts showed significantly greater bond strength than prefabricated posts when luted with either resin or zinc phosphate cements. The type of cement had less significance on the retention of custom cast posts.

[Effect of a nano hydroxyapatite desensitizing paste application on dentin bond strength of three self-etch adhesive systems].

PubMed

Pei, D D; Liu, S Y; Yang, H Y; Gan, J; Huang, C

2017-05-09

Objective: To evaluate a nano-hydroxyapatite (nano-HA) desensitizing paste application on the bond strength of three self-etch adhesives. Methods: Three dentin specimens of about 1 mm thick were cut from two teeth. Scanning electron microscope (SEM) was used to evaluate the dentin surfaces without treatment, after citric acid treatment and after nano-HA treatment. Thirty-six intact third molars extracted for surgical reasons were cut to remove the occlusal enamel with isomet, and then were etched with 1% citric acid for 20 s to simulate the sensitive dentin and divided into two groups randomly using a table of random numbers ( n= 18): the control group (no treatment) and the HA treated group (with nano-HA paste treatment). Each group was divided into three subgroups randomly using a table of random numbers ( n= 6). Subgroup A, B and C was bonded with G-Bond, Clearfil S(3) Bond and FL-Bond Ⅱ according to the manufacture's instruction separately. At 24 h after bonding procedure, and after water storage for 6 months, microtensile bond strength of the specimens was tested and the failure mode was analyzed. Results: SEM obeservation showed that citric acid could open the dentin tubules to set up the sensitive dentin model, and the nano-HA could occlude the dentin tubules effectively. For subgroup A, bonding strength of specimens treated with nano-HA ([41.14±8.91] MPa) was significantly high than that of the control group ([34.27±6.16] MPa) at 24 h after bonding procedure ( P< 0.05). However, after 6 month water ageing, the bonding strength of the control group and the HA treated group showed no significant difference ( P> 0.05). For subgroup B, specimens with nano-HA application showed lower bonding strength ([30.87±6.41] MPa) than that of the control group ([36.73±5.82] MPa) at 24 h after bonding procedure ( P< 0.05), and after 6 month water ageing, the bond strength of nano-HA application ([25.73±6.99] MPa) was also lower than that of the control group ([32.33±5.08] MPa) ( P< 0.05). For subgroup C, the bond strength of the control group and the HA treated group have no significant difference either before or after 6 month water ageing ( P> 0.05). Failure mode analysis showed that more than half of the samples in all groups were adhesive failure. Conclusions: Nano-HA treatment decreased the bond strength of subgroup B, while had no adverse effect on subgroup A and subgroup C.

Interconnect mechanisms in microelectronic packaging

NASA Astrophysics Data System (ADS)

Roma, Maria Penafrancia C.

Global economic, environmental and market developments caused major impact in the microelectronics industry. Astronomical rise of gold metal prices over the last decade shifted the use of copper and silver alloys as bonding wires. Environmental legislation on the restriction of the use of Pb launched worldwide search for lead-free solders and platings. Finally, electrical and digital uses demanded smaller, faster and cheaper devices. Ultra-fine pitch bonding, decreasing bond wire sizes and hard to bond substrates have put the once-robust stitch bond in the center of reliability issues due to stitch bond lift or open wires .Unlike the ball bond, stitch bonding does not lead to intermetallic compound formation but adhesion is dependent on mechanical deformation, interdiffusion, solid solution formation, void formation and mechanical interlocking depending on the wire material, bond configuration, substrate type , thickness and surface condition. Using Au standoff stitch bonds on NiPdAu plated substrates eliminated stitch bond lift even when the Au and Pd layers are reduced. Using the Matano-Boltzmann analysis on a STEM (Scanning Transmission Analysis) concentration profile the interdiffusion coefficient is measured to be 10-16 cm 2/s. Wire pull strength data showed that the wire pull strength is 0.062N and increases upon stress testing. Meanwhile, coating the Cu wire with Pd, not only increases oxidation resistance but also improved adhesion due to the formation of a unique interfacial adhesion layers. Adhesion strength as measured by pull showed the Cu wire bonded to Ag plated Cu substrate (0.132N) to be stronger than the Au wire bonded on the same substrate (0.124N). Ag stitch bonded to Au is predicted to be strong but surface modification made the adhesion stronger. However, on the Ag ball bonded to Al showed multiple IMC formation with unique morphology exposed by ion milling and backscattered scanning electron microscopy. Adding alloying elements in the Ag wire alloy showed differences in adhesion strength and IMC formation. Bond strength by wire pull testing showed the 95Ag alloy with higher values while shear bond testing showed the 88Ag higher bond strength. Use of Cu pillars in flip chips and eutectic bonding in wafer level chip scale packages are direct consequences of diminishing interconnect dimension as a result of the drive for miniaturization. The combination of Cu-Sn interdiffusion, Kirkendall mechanism and heterogeneous vacancy precipitation are the main causes of IMC and void formation in Cu pillar - Sn solder - Cu lead frame sandwich structure. However, adding a Ni barrier agent showed less porous IMC layer as well as void formation as a result of the modified Cu and Sn movement well as the void formation. Direct die to die bonding using Al-Ge eutectic bonds is necessary when 3D integration is needed to reduce the footprint of a package. Hermeticity and adhesion strength are a function of the Al/Ge thickness ratio, bonding pressure, temperature and time. Scanning Electron Microscope (SEM) and Focused Ion Beam (FIB) allowed imaging of interfacial microstructures, porosity, grain morphology while Scanning Transmission Electron microscope (STEM) provided diffusion profile and confirmed interdiffusion. Ion polishing technique provided information on porosity and when imaged using backscattered mode, grain structure confirmed mechanical deformation of the bonds. Measurements of the interfacial bond strength are made by wire pull tests and ball shear tests based on existing industry standard tests. However, for the Al-Ge eutectic bonds, no standard strength is available so a test is developed using the stud pull test method using the Dage 4000 Plus to yield consistent results. Adhesion strengths of 30-40 MPa are found for eutectic bonded packages however, as low as 20MPa was measured in low temperature bonded areas.

Orthodontic brackets removal under shear and tensile bond strength resistance tests - a comparative test between light sources

NASA Astrophysics Data System (ADS)

Silva, P. C. G.; Porto-Neto, S. T.; Lizarelli, R. F. Z.; Bagnato, V. S.

2008-03-01

We have investigated if a new LEDs system has enough efficient energy to promote efficient shear and tensile bonding strength resistance under standardized tests. LEDs 470 ± 10 nm can be used to photocure composite during bracket fixation. Advantages considering resistance to tensile and shear bonding strength when these systems were used are necessary to justify their clinical use. Forty eight human extracted premolars teeth and two light sources were selected, one halogen lamp and a LEDs system. Brackets for premolar were bonded through composite resin. Samples were submitted to standardized tests. A comparison between used sources under shear bonding strength test, obtained similar results; however, tensile bonding test showed distinct results: a statistical difference at a level of 1% between exposure times (40 and 60 seconds) and even to an interaction between light source and exposure time. The best result was obtained with halogen lamp use by 60 seconds, even during re-bonding; however LEDs system can be used for bonding and re-bonding brackets if power density could be increased.

Experimetal study on the FRP-concrete bond behavior under repeated loadings

NASA Astrophysics Data System (ADS)

Lee, J.-Y.; Yi, C.-K.; Cheong, Y.-G.

2009-11-01

In this study, the effects of repeated loads on the FRP-concrete bond strength were investigated experimentally by direct pull out tests according to CSA S806-02. A conventional reinforcing steel bar and two types of glass-fiber-reinforced plastic (GFRP) bars were embedded in concrete and tested under four different loading patterns. The bond strength-slip curves of the bars were obtained and analyzed. The results showed that the maximum bond strengths under the repeated loads differed from those obtained under monotonic ones. In addition, noticeable differences in degradation of the bond strength with respect to the magnitude of slip were observed between the different bar types tested. On the basis of an image analysis of failure surfaces, they were attributed to the different bond failure mechanisms associated with the steel and GFRP bars.

[Effect of a chemical primer on the bond strength of a zirconia ceramic with self-adhesive resin cement].

PubMed

Zhang, Hong; Jing, Ye; Nie, Rongrong; Meng, Xiangfeng

2015-10-01

To evaluate the bond strength and durability of a self-adhesive resin cement with a zirconia ceramic pretreated by a zirconia primer. Zirconia ceramic (Vita Inceram YZ) plates with a thickness of 2.5 mm were fired, polished, and then cleaned. Half of the polished ceramic plates were sandblasted with 50 μm alumina particles at 0.3 MPa for 20 s. The surface compound weight ratios were measured via X-ray fluorescence microscopy. The polished and sandblasted ceramic plates were directly bonded with self-adhesive resin cement (Biscem) or were pretreated by a zirconia primer (Z Primer Plus) before bonding with Biscem. The specimens of each test group were divided into two subgroups (n=10) and subjected to the shear test after 0 and 10,000 thermal cycles. The data were analyzed via three-way ANOVA. After air abrasion, 8.27% weight ratio of alumina attached to the zirconia surface. Compared with air abrasion, primer treatment more significantly improved the primary resin bond strength of the zirconia ceramic. The primary resin bond strength of the zirconia ceramic with no primer treatment was not affected by thermocycling (P>0.05). However, the primary resin bond strength of the zirconia ceramic with primer treatment was significantly decreased by thermocycling (P<0.05). Primer treatment can improve the primary resin bond strengths of zirconia ceramics. However, the bond interface of the primer is not stable and rapidly degraded during thermocycling.

Effects of long-term repeated topical fluoride applications and adhesion promoter on shear bond strengths of orthodontic brackets

PubMed Central

Endo, Toshiya; Ishida, Rieko; Komatsuzaki, Akira; Sanpei, Shinya; Tanaka, Satoshi; Sekimoto, Tsuneo

2014-01-01

Objective: The purpose of this study was to assess the effects of long-term repeated topical application of fluoride before bonding and an adhesion promoter on the bond strength of orthodontic brackets. Materials and Methods: A total of 76 bovine incisors were collected and divided equally into four groups. In group 1, the brackets were bonded without topical fluoride application or adhesion promoter. In group 2, before bonding, the adhesion promoter was applied to nonfluoridated enamel. In group 3, the brackets were bonded without the application of the adhesion promoter to enamel, which had undergone long-term repeated topical fluoride treatments. Teeth in group 4 received the long-term repeated topical applications of fluoride, and the brackets were bonded using the adhesion promoter. All the brackets were bonded using BeautyOrtho Bond self-etching adhesive. The shear bond strength was measured and the bond failure modes were evaluated with the use of the adhesive remnant index (ARI) after debonding. Results: The mean shear bond strength was significantly lower in group 3 than in groups 1, 2, and 4, and there were no significant differences between the groups except for group 3. There were significant differences in the distribution of ARI scores between groups 2 and 3, and between groups 3 and 4. Conclusions: The adhesion promoter can recover the bond strength reduced by the long-term repeated topical applications of fluoride to the prefluoridation level and had a significantly great amount of adhesives left on either fluoridated or nonfluoridated enamel. PMID:25512720

Microshear Bond Strength of Tri-Calcium Silicate-based Cements to Different Restorative Materials.

PubMed

Cengiz, Esra; Ulusoy, Nuran

To evaluate the microshear bond strength of tri-calcium silicate-based materials to different restorative materials. Thirty-five disks of TheraCal LC and Biodentine were fabricated using teflon molds according to manufacturers' instructions. Then the specimens were randomly divided into 7 groups according to the materials applied: Fuji IX, Fuji II, Equia Fil, Vertise Flow, Filtek Bulk Fill Posterior Restorative, Filtek Z250 with Prime&Bond NT and with Clearfil SE Bond. All restorative materials were placed onto the disks using tygon tubes. Following a storage period, the specimens underwent microshear bond strength testing in a universal testing machine, and fracture modes were analyzed. Data were analyzed using one-way ANOVA and Tukey's post-hoc test. For all restorative materials, TheraCal LC showed significantly higher μSBS values compared to Biodentine. GIC based materials showed the lowest μSBS for TheraCal and Biodentine. For Biodentine, Filtek Z250 applied with Prime&Bond NT and Filtek Bulk Fill Posterior Restorative applied with Scotchbond Universal Adhesive exhibited the highest μSBS, while Filtek Z250 applied with Clearfil SE Bond revealed the highest bond strength to TheraCal LC. For all restorative materials tested in this study, TheraCal LC showed higher μSBS compared to Biodentine. For both TheraCal LC and Biodentine, the placement of GIC-based materials prior to composite resin restorations might decrease the bond strength. Composite resins applied with self-etching adhesives increased the bond strength of TheraCal LC; however, for Biodentine, application of etch-and-rinse adhesives may improve the adhesion of composite resins.

Effects of moisture conditions of dental enamel surface on bond strength of brackets bonded with moisture-insensitive primer adhesive system.

PubMed

Endo, Toshiya; Ozoe, Rieko; Sanpei, Sugako; Shinkai, Koichi; Katoh, Yoshiroh; Shimooka, Shohachi

2008-07-01

The purposes of this study were to evaluate the effects of different degrees of water contamination on the shear bond strength of orthodontic brackets bonded to dental enamel with a moisture-insensitive primer (MIP) adhesive system and to compare the modes of bracket/adhesive failure. A total of 68 human premolars were divided into four groups by primers and enamel surface conditions (desiccated, blot dry, and overwet). In group I, the hydrophobic Transbond XT primer adhesive system was used under desiccated conditions for bonding the brackets; in group II, the hydrophilic Transbond MIP adhesive system was used under desiccated conditions; in group III, the hydrophilic Transbond MIP adhesive system was used under blot dry conditions; and in group IV, the hydrophilic Transbond MIP adhesive system was used under overwet conditions. Shear bond strength was measured with a universal testing machine, and the mode of bracket/adhesive failure was determined according to the adhesive remnant index. The mean shear bond strengths were not significantly different among groups I, II, and III, and were higher than the clinically required range of 6 to 8 MPa. The mean shear bond strength achieved in group IV was significantly lower than that achieved in groups I, II, and III, and also lower than the clinically required values. Bond failure occurred at the enamel-adhesive interface more frequently in group IV than in groups I and III. To achieve clinically sufficient bond strengths with the hydrophilic MIP adhesive system, excess water should be blotted from the water-contaminated enamel surface.

In vitro tensile bond strength of adhesive cements to new post materials.

PubMed

O'Keefe, K L; Miller, B H; Powers, J M

2000-01-01

The purpose of this study was to measure the in vitro tensile bond strength of 3 types of adhesive resin cements to stainless steel, titanium, carbon fiber-reinforced resin, and zirconium oxide post materials. Disks of post materials were polished to 600 grit, air abraded, and ultrasonically cleaned. Zirconium oxide bonding surfaces were pretreated with hydrofluoric acid and silanated. Bis-Core, C&B Metabond, and Panavia cements were bonded to the post specimens and placed in a humidor for 24 hours. Post specimens were debonded in tension. Means and standard deviations (n = 5) were analyzed by 2-way analysis of variance. Tukey-Kramer intervals at the 0.05 significance level were calculated. Failure modes were observed. Panavia 21 provided the highest bond strengths for all types of post materials, ranging from 22 MPa (zirconium oxide) to 37 MPa (titanium). C&B Metabond bonded significantly more strongly to stainless steel (27 MPa) and titanium (22 MPa) than to zirconium oxide (7 MPa). Bis-Core results were the lowest, ranging from 16 MPa (stainless steel) to 8 MPa (zirconium oxide). In most cases, bonds to carbon fiber post materials were weaker than to stainless steel and titanium, but stronger than to zirconium oxide. In general, higher bond strengths resulted in a higher percentage of cohesive failures within the cement. Panavia 21 provided the highest bond strengths to all post materials, followed by C&B Metabond. In most cases, adhesive resins had higher bond strengths to stainless steel, titanium, and carbon fiber than to zirconium oxide.

Evaluating the bonding of two adhesive systems to enamel submitted to whitening dentifrices.

PubMed

Briso, André Luiz Fraga; Toseto, Roberta Mariano; de Arruda, Alex Mendes; Tolentino, Patricia Ramos; de Alexandre, Rodrigo Sversut; dos Santos, Paulo Henrique

2010-01-01

The aim of this study was to evaluate by micro-shear bond strength test, the bond strength of composite resin restoration to enamel submitted to whitening dentifrices. Forty bovine teeth were embedded in polystyrene resin and polished. The specimens were randomly divided into eight groups (n=5), according to the dentifrice (carbamide peroxide, hydrogen peroxide and conventional dentifrice) and the adhesive system (Prime & Bond 2.1 and Adper Single Bond 2). Dentifrice was applied for 15 minutes a day, for 21 days. Thirty minutes after the last exposure to dentifrice, the samples were submitted to a bonding procedure with the respective adhesive system. After that, four buttons of resin were bonded in each sample using transparent cylindrical molds. After 24 hours, the teeth were submitted to the micro-shear bond strength test and subsequent analysis of the fracture mode. Data were submitted to analysis of variance and Fisher's PLSD test (alpha = 0.05). The micro-shear bond strength showed no difference between adhesives systems but a significant reduction was found between the control and carbamide groups (p = 0.0145) and the control and hydrogen groups (p = 0.0370). The evaluation of the failures modes showed that adhesive failures were predominant. Cohesive failures were predominant in group IV The use of dentifrice with peroxides can decrease bonding strength in enamel.

Effect of etching on bonding of a self-etch adhesive to dentine affected by amelogenesis imperfecta.

PubMed

Epasinghe, Don Jeevanie; Yiu, Cynthia Kar Yung

2018-02-01

Dentine affected by amelogenesis imperfecta (AI) is histologically altered due to loss of hypoplastic enamel and becomes hypermineralized. In the present study, we examined the effect of additional acid etching on microtensile bond strength of a self-etch adhesive to AI-affected dentine. Flat coronal dentine obtained from extracted AI-affected and non-carious permanent molars were allocated to two groups: (a) Clearfil SE Bond (control); and (b) Clearfil SE Bond and additional etching with 34% phosphoric acid for 15 seconds. The bonded teeth were sectioned into .8-mm 2 beams for microtensile bond strength testing, and stressed to failure under tension. The bond strength data were analyzed using two-way analysis of variance (dentine type and etching step) and Student-Newman-Keuls multiple comparison test (P<.05). Representative fractured beams from each group were examined under scanning electron microscopy. Both factors, dentine substrate (P<.001) and etching step (P<.05), and their interactions (P<.001), were statistically significant. Additional etching had an adverse effect on the bond strength of Clearfil SE Bond to normal dentine (P<.005), and no significant improvement was found for AI-affected dentine (P=.479). Additional acid etching does not improve the bond strength of a self-etch adhesive to AI-affected dentine. © 2017 John Wiley & Sons Australia, Ltd.

Effect of Fluoride and Simplified Adhesive Systems on the Bond Strength of Primary Molars and Incisors.

PubMed

Firoozmand, Leily Macedo; Noleto, Lawanne Ellen Carvalho; Gomes, Isabella Azevedo; Bauer, José Roberto de Oliveira; Ferreira, Meire Coelho

2015-01-01

The aim of this study was evaluate in vitro the influence of simplified adhesive systems (etch-and-rinse and self-etching) and 1.23% acidulated phosphate fluoride (APF) on the microshear bond strength (μ-SBS) of composite resins on primary molars and incisors. Forty primary molars and forty incisors vestibular enamel was treated with either the self-etching Clearfil SE Bond (CSE, Kuraray) or etch-and-rinse Adper Single Bond 2 (SB2, 3M/ESPE) adhesive system. Each group was subdivided based on the prior treatment of the enamel with or without the topical application of 1.23% APF. Thereafter, matrices were positioned and filled with composite resin and light cured. After storage in distilled water at 37 ± 1°C for 24 h, the specimens were submitted to μ-SBS in a universal testing machine. Kruskal-Wallis and Mann-Whitney tests (p < 0.05) showed that the prior application of 1.23% APF led to a significant reduction in bond strength. The type of adhesive exerted no significant influence bond strength. In the inter-group analysis, however, significantly bond strength reduction was found for the incisors when CSE was employed with APF. Adhesive failure was the most common type of fracture. The bond strength was affected by the prior application of 1.23% APF and type of tooth.

[Effect of casein phosphopeptide-amorphouscalcium phosphate (CPP-ACP) treatment on the shear bond strength of orthodontic brackets after tooth bleaching].

PubMed

Lu, Jing; Ding, Xiao-jun; Yu, Xiao-ping; Gong, Yi-ming

2015-10-01

To evaluate the effect of casein phosphopeptide-amorphouscalcium phosphate (CPP-ACP) treatment on the shear bond strength of orthodontic brackets after tooth bleaching. One hundred extracted human premolars were randomly divided and treated according to 5 groups (n=20) : (1) no treatment; (2) 10% carbamide peroxide bleaching; (3) 38% hydrogen peroxide bleaching; (4)10% carbamide peroxide bleaching and CPP-ACP paste; (5)38% hydrogen peroxide bleaching and CPP-ACP paste. In all groups, the brackets were bonded using a conventional acid-etch and bond system (Transbond XT, 3M Unitek, Monrovia, Calif). The shear bond strength adhesive remnant index (ARI) of the brackets were determined and the data was analyzed by ANOVA and Bonferroni test using SPSS13.0 software package. The use of 10% carbamide peroxide and 38% hydrogen peroxide bleaching significantly decreased the shear bond strength of orthodontic brackets when compared with untreated group (P<0.05). After combination of tooth bleaching and CPP-ACP treatment, group 4 (10% carbamide peroxide bleaching + CPP-ACP) and group 5 (38% hydrogen peroxide bleaching + CPP-ACP) showed higher levels of shear bond strength than group 2 and 3; however, no significant difference was found (P>0.05). The ARI did not show any significant difference before and after CPP-ACP treatment. After tooth bleaching, CPP-ACP treatment have little influence on the shear bond strength of orthodontic brackets.

Effects of dentin surface treatments on shear bond strength of glass-ionomer cements

PubMed Central

Poggio, Claudio; Beltrami, Riccardo; Scribante, Andrea; Colombo, Marco; Lombardini, Marco

2014-01-01

Summary Aim The aim of this in vitro study was to evaluate the effect of different surface treatments on shear bond strength of a conventional glass-ionomer cement (GIC) and a resin-modified glass-ionomer cement (RMGIC) to dentin. Materials and methods 80 bovine permanent incisors were used. 40 cylindrical specimens of a GIC (Fuji IX GP Extra) and 40 cylindrical specimens of a RMGIC (Fuji II LC) were attached to the dentin. The teeth were then randomly assigned to 8 groups of equal size (n=10), 4 for every type of glass-ionomer cement, corresponding to type of dentin surface treatments. Group 1: GC Cavity Conditioner; Group 2: 37% phosphoric acid gel; Group 3: Clearfil SE Bond; Group 4: no dentin conditioning (control). The specimens were placed in a universal testing machine (Model 3343, Instron Corp., Canton, Mass., USA) and subsequently tested for shear bond strength (MPa). Results ANOVA showed the presence of significant differences among the various groups. Post hoc Tukey test showed different values of shear bond strength for Fuji IX GP Extra and for Fuji II LC. The different conditioners variably influence the adhesion of the glass-ionomer cements tested. Conclusions. RMGIC shear bond to dentin was higher than GIC. The use of a Self-etch adhesive system improved the shear bond strength values of RMGIC and lowered the shear bond strength values of GIC significantly. PMID:24753797

Bonding durability between acrylic resin adhesives and titanium with surface preparations.

PubMed

Yanagida, Hiroaki; Minesaki, Yoshito; Matsumura, Kousuke; Tanoue, Naomi; Muraguchi, Koichi; Minami, Hiroyuki

2017-01-31

The purpose of the present study was to evaluate the efficacy of pretreatment on the bonding durability between titanium casting and two acrylic adhesives. Cast titanium disk specimens treated with four polymer-metal bonding systems as follow: 1) air-abraded with 50-70 μm alumina, 2) 1)+Alloy Primer, 3) 1)+M.L. Primer and 4) tribochemical silica/silane coating system (Rocatec System). The specimens were bonded with M bond or Super-bond C&B adhesive. The shear bond strengths were determined before and after thermocycling (20,000 cycles). The surface characteristics after polishing, and for the 1) and 4) preparations were determined. The bond strengths for all combinations significantly decreased after thermocycling. The combination of Super-bond C&B adhesive and 2) led to significantly higher bond strength than the other preparations after thermocycling. The maximum height of the profile parameters for the polishing group was lower than other preparations.

In vitro evaluation of casein phosphopeptide-amorphous calcium phosphate effect on the shear bond strength of dental adhesives to enamel.

PubMed

Shadman, Niloofar; Ebrahimi, Shahram Farzin; Shoul, Maryam Azizi; Sattari, Hasti

2015-01-01

Casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) is applied for remineralization of early caries lesions or tooth sensitivity conditions and may affect subsequent resin bonding. This in vitro study investigated the effect of CPP-ACP on the shear bond strength of dental adhesives to enamel. Sixty extracted human molar teeth were selected and randomly divided into three groups and six subgroups. Buccal or lingual surfaces of teeth were prepared to create a flat enamel surface. Adhesives used were Tetric N-Bond, AdheSE and AdheSE One F. In three subgroups, before applying adhesives, enamel surfaces were treated with Tooth Mousse CPP-ACP for one hour, rinsed and stored in 37°C temperature with 100% humidity. This procedure was repeated for 5 days and then adhesives were applied and Tetric N-Ceram composite was adhered to the enamel. This procedure was also fulfilled for the other three subgroups without CPP-ACP treatment. After 24 hour water storage, samples were tested for shear bond strength test in a universal testing machine. Failure modes were determined by stereomicroscope. Data were analyzed by t-test and one-way analysis of variance with P < 0.05 as the level of significance. In comparison between applied and non-applied CPP-ACP subgroups, there was no significant decrease in the shear bond strength to enamel only in Tetric N-Bond (P > 0.05). In non-applied CPP-ACP subgroups, there were statistically significant differences among all subgroups. Tetric N-Bond had the highest and AdheSE One F had the lowest shear bond strength. CPP-ACP application reduces the shear bond strength of AdheSE and AdheSE One F to enamel but not Tetric N-Bond.

Effect of Delayed Bonding and Antioxidant Application on the Bond Strength to Enamel after Internal Bleaching.

PubMed

Kılınç, Halil İbrahim; Aslan, Tuğrul; Kılıç, Kerem; Er, Özgür; Kurt, Gökmen

2016-07-01

This study evaluated the effect of delayed bonding and antioxidant application (AA, 10% sodium ascorbate) after internal bleaching (35% carbamide peroxide) on the shear bond strength of an adhesive cement to enamel. Eighty-four human maxillary central incisors were endodontically treated. The control group remained unbleached with no AA. Experimental groups were all internally bleached. The buccal enamel was finished and polished with metallographic paper to a refinement of #600, in order to obtain a 5-mm(2) flat bonding area. An adhesive cement (Clearfil Esthetic) was placed into a plastic tube with internal diameter of 3 mm and a 3-mm height and cured on the enamel. Bonding occurred either immediately after bleaching (group Im), a 7-day delay (group 7), or a 14-day delay (group 14), and half the specimens were treated with antioxidant application (groups Im-AA, 7-AA, and 14-AA). Shear bond strength testing was performed on a universal testing machine, and data were analyzed with ANOVA and Fisher test (5%). Delaying of bonding is a useful factor for enhancing shear bond strength (p < 0.05), whereas AA only enhanced shear bond strength after 7 days delayed bleaching (p < 0.05). The highest bond strength was noted in groups 7-AA (20.51 ± 4.5 MPa), 14 (19.82 ± 4.6), 14-AA (20.27 ± 4.4), and control (20.51 ± 5.1), which were not significantly different from each other. After internal bleaching, adhesive cementation to enamel is recommended only when delayed 14 days, or delayed 7 days with sodium ascorbate application. © 2015 by the American College of Prosthodontists.

In vitro evaluation of casein phosphopeptide-amorphous calcium phosphate effect on the shear bond strength of dental adhesives to enamel

PubMed Central

Shadman, Niloofar; Ebrahimi, Shahram Farzin; Shoul, Maryam Azizi; Sattari, Hasti

2015-01-01

Background: Casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) is applied for remineralization of early caries lesions or tooth sensitivity conditions and may affect subsequent resin bonding. This in vitro study investigated the effect of CPP-ACP on the shear bond strength of dental adhesives to enamel. Materials and Methods: Sixty extracted human molar teeth were selected and randomly divided into three groups and six subgroups. Buccal or lingual surfaces of teeth were prepared to create a flat enamel surface. Adhesives used were Tetric N-Bond, AdheSE and AdheSE One F. In three subgroups, before applying adhesives, enamel surfaces were treated with Tooth Mousse CPP-ACP for one hour, rinsed and stored in 37°C temperature with 100% humidity. This procedure was repeated for 5 days and then adhesives were applied and Tetric N-Ceram composite was adhered to the enamel. This procedure was also fulfilled for the other three subgroups without CPP-ACP treatment. After 24 hour water storage, samples were tested for shear bond strength test in a universal testing machine. Failure modes were determined by stereomicroscope. Data were analyzed by t-test and one-way analysis of variance with P < 0.05 as the level of significance. Results: In comparison between applied and non-applied CPP-ACP subgroups, there was no significant decrease in the shear bond strength to enamel only in Tetric N-Bond (P > 0.05). In non-applied CPP-ACP subgroups, there were statistically significant differences among all subgroups. Tetric N-Bond had the highest and AdheSE One F had the lowest shear bond strength. Conclusion: CPP-ACP application reduces the shear bond strength of AdheSE and AdheSE One F to enamel but not Tetric N-Bond. PMID:25878683

The effect of Er:YAG laser irradiation on the bond stability of self-etch adhesives at different dentin depths.

PubMed

Karadas, Muhammet; Çağlar, İpek

2017-07-01

The aim of this study was to evaluate the effect of Er:YAG laser irradiation on the micro-shear bond strength of self-etch adhesives to the superficial dentin and the deep dentin before and after thermocycling. Superficial dentin and deep dentin surfaces were prepared by flattening of the occlusal surfaces of extracted human third molars. The deep or superficial dentin specimens were randomized into three groups according to the following surface treatments: group I (control group), group II (Er:YAG laser; 1.2 W), and group III (Er:YAG laser; 0.5 W). Clearfil SE Bond or Clearfil S 3 Bond was applied to each group's dentin surfaces. After construction of the composite blocks on the dentin surface, the micro-shear bond testing of each adhesive was performed at 24 h or after 15,000 thermal cycles. The data were analyzed using a univariate analysis of variance and Tukey's test (p < 0.05). Laser irradiation in superficial dentin did not significantly affect bond strength after thermocycling (p > 0.05). However, deep-dentin specimens irradiated with laser showed significantly higher bond strengths than did control specimens after thermocycling (p < 0.05). Thermocycling led to significant deterioration in the bond strengths of all deep-dentin groups. The stable bond strength after thermocycling was measured for all of the superficial-dentin groups. No significant difference was found between the 0.5 and 1.2 W output power settings. In conclusion, the effect of laser irradiation on the bond strength of self-etch adhesives may be altered by the dentin depth. Regardless of the applied surface treatment, deep dentin showed significant bond degradation.

Effect of Peracetic Acid as A Final Rinse on Push Out Bond Strength of Root Canal Sealers to Root Dentin.

PubMed

Gaddala, Naresh; Veeramachineni, Chandrasekhar; Tummala, Muralidhar

2015-05-01

Smear layer which was formed during the instrumentation of root canals hinders the penetration of root canal sealers to root dentin and affect the bond strength of root canal sealers to root dentin. Final irrigant such as demineralizing agents are used to remove the inorganic portion of the smear layer. In the present study, peracetic acid used as a final rinse, to effect the bond strength of root canal sealers to root dentin. The purpose of the present study was to evaluate the efficacy of peracetic acid as a final irrigant on bond strength of root canal sealers to root dentin. Sixty six freshly extracted human single rooted mandibular premolars were used for this study. After decoronation the samples were instrumented with Protaper upto F3 and irrigated with 5.25% NaOcl. The teeth were then divided into three groups based on final irrigant used: Group-1(control group) Canals were irrigated with distilled water. Group-2: Canals were irrigated with peracetic acid. Group-3: Canals were irrigated with smear clear. Each group was further divided into three subgroups (n=30) based on the sealer used to obturate the canals. Subgroup-1: kerr, Subgroup-2: Apexit plus, Subgroup-3: AH PLUS. Each sealer was mixed and coated to master cone and placed in the canal. The bonding between sealer and dentin surface was evaluated using push out bond strength by universal testing machine. The mean bond strength values of each group were statistically evaluated using Two-way ANOVA followed by Tukey post-hoc test. Significant difference was found among the bond strength of the sealers. But, there is no statistically significant difference between the groups irrigated with peracetic acid and smear clear compared to control group. AH Plus showed highest bond strength irrespective of the final irrigant used. Peracetic acid when employed as final irrigant improved the bond strength of root canal sealers compared to control group but not statistically significant than smear clear.

Effect of Peracetic Acid as A Final Rinse on Push Out Bond Strength of Root Canal Sealers to Root Dentin

PubMed Central

Gaddala, Naresh; Veeramachineni, Chandrasekhar

2015-01-01

Background Smear layer which was formed during the instrumentation of root canals hinders the penetration of root canal sealers to root dentin and affect the bond strength of root canal sealers to root dentin. Final irrigant such as demineralizing agents are used to remove the inorganic portion of the smear layer. In the present study, peracetic acid used as a final rinse, to effect the bond strength of root canal sealers to root dentin. Aim The purpose of the present study was to evaluate the efficacy of peracetic acid as a final irrigant on bond strength of root canal sealers to root dentin. Materials and Methods Sixty six freshly extracted human single rooted mandibular premolars were used for this study. After decoronation the samples were instrumented with Protaper upto F3 and irrigated with 5.25% NaOcl. The teeth were then divided into three groups based on final irrigant used: Group-1(control group) Canals were irrigated with distilled water. Group-2: Canals were irrigated with peracetic acid. Group-3: Canals were irrigated with smear clear. Each group was further divided into three subgroups (n=30) based on the sealer used to obturate the canals. Subgroup-1: kerr, Subgroup-2: Apexit plus, Subgroup-3: AH PLUS. Each sealer was mixed and coated to master cone and placed in the canal. The bonding between sealer and dentin surface was evaluated using push out bond strength by universal testing machine. The mean bond strength values of each group were statistically evaluated using Two-way ANOVA followed by Tukey post-hoc test. Results Significant difference was found among the bond strength of the sealers. But, there is no statistically significant difference between the groups irrigated with peracetic acid and smear clear compared to control group. AH Plus showed highest bond strength irrespective of the final irrigant used. Conclusion Peracetic acid when employed as final irrigant improved the bond strength of root canal sealers compared to control group but not statistically significant than smear clear. PMID:26155568

Bond strength of one-step self-etch adhesives and their predecessors to ground versus unground enamel

PubMed Central

Yazici, A. Ruya; Yildirim, Zeren; Ertan, Atila; Ozgunaltay, Gül; Dayangac, Berrin; Antonson, Sibel A; Antonson, Donald E

2012-01-01

Objective The aim of this study was to compare the shear bond strength of several self-etch adhesives to their two-step predecessors to ground and unground enamel. Methods: Seventy-five extracted, non-carious human third molar teeth were selected for this study. The buccal surfaces of each tooth were mechanically ground to obtain flat enamel surfaces (ground enamel), while the lingual surfaces were left intact (unground enamel). The teeth were randomly divided into five groups according to the adhesive systems (n=15): one-step self-etch adhesive - Clearfil S3 Bond, its two-step predecessor - Clearfil SE Bond, one-step self-etch adhesive - AdheSE One, and its two-step predecessor - AdheSE, and a two-step etch-and-rinse adhesive - Adper Single Bond 2(control). After application of the adhesives to the buccal and lingual enamel surfaces of each tooth, a cylindrical capsule filled with a hybrid composite resin (TPH) was seated against the surfaces. The specimens were stored in distilled water at 37°C for 24 hours, followed by thermocy-cling (5°C–55°C/500 cycles). They were subjected to shear bond strength test in a universal testing machine at a crosshead speed of 1.0 mm/minute. The data were compared using a two-way ANOVA, followed by Bonferroni test at P<.05. Results: All adhesives exhibited statistically similar bond strengths to ground and unground enamel except for the etch-and-rinse adhesive that showed significantly higher bond strengths than the self-etch adhesives (P<.05). No significant differences in bond strength values were observed between ground and unground enamel for any of the adhesives tested (P=.17). Conclusion: Similar bond strengths to ground and unground enamel were achieved with one-step self-etch adhesives and their predecessors. Enamel preparation did not influence the bonding performance of the adhesives tested. PMID:22904656

Bond strength of one-step self-etch adhesives and their predecessors to ground versus unground enamel.

PubMed

Yazici, A Ruya; Yildirim, Zeren; Ertan, Atila; Ozgunaltay, Gül; Dayangac, Berrin; Antonson, Sibel A; Antonson, Donald E

2012-07-01

The aim of this study was to compare the shear bond strength of several self-etch adhesives to their two-step predecessors to ground and unground enamel. Seventy-five extracted, non-carious human third molar teeth were selected for this study. The buccal surfaces of each tooth were mechanically ground to obtain flat enamel surfaces (ground enamel), while the lingual surfaces were left intact (unground enamel). The teeth were randomly divided into five groups according to the adhesive systems (n=15): one-step self-etch adhesive - Clearfil S3 Bond, its two-step predecessor - Clearfil SE Bond, one-step self-etch adhesive - AdheSE One, and its two-step predecessor - AdheSE, and a two-step etch-and-rinse adhesive - Adper Single Bond 2(control). After application of the adhesives to the buccal and lingual enamel surfaces of each tooth, a cylindrical capsule filled with a hybrid composite resin (TPH) was seated against the surfaces. The specimens were stored in distilled water at 37°C for 24 hours, followed by thermocy-cling (5°C-55°C/500 cycles). They were subjected to shear bond strength test in a universal testing machine at a crosshead speed of 1.0 mm/minute. The data were compared using a two-way ANOVA, followed by Bonferroni test at P<.05. All adhesives exhibited statistically similar bond strengths to ground and unground enamel except for the etch-and-rinse adhesive that showed significantly higher bond strengths than the self-etch adhesives (P<.05). No significant differences in bond strength values were observed between ground and unground enamel for any of the adhesives tested (P=.17). Similar bond strengths to ground and unground enamel were achieved with one-step self-etch adhesives and their predecessors. Enamel preparation did not influence the bonding performance of the adhesives tested.

Shear bond strength of porcelain laminate veneers to enamel, dentine and enamel-dentine complex bonded with different adhesive luting systems.

PubMed

Öztürk, Elif; Bolay, Şükran; Hickel, Reinhard; Ilie, Nicoleta

2013-02-01

The aim of this study was to evaluate the shear bond strength of porcelain laminate veneers to 3 different surfaces by means of enamel, dentine, and enamel-dentine complex. One hundred thirty-five extracted human maxillary central teeth were used, and the teeth were randomly divided into 9 groups (n=15). The teeth were prepared with 3 different levels for bonding surfaces of enamel (E), dentine (D), and enamel-dentine complex (E-D). Porcelain discs (IPS e.max Press, Ivoclar Vivadent) of 2mm in thickness and 4mm in diameter were luted to the tooth surfaces by using 2 light-curing (RelyX Veneer [RV], 3M ESPE; Variolink Veneer [VV], Ivoclar Vivadent) and a dual-curing (Variolink II [V2], Ivoclar Vivadent) adhesive systems according to the manufacturers' instructions. Shear bond strength test was performed in a universal testing machine at 0.5mm/min until bonding failure. Failure modes were determined under a stereomicroscope, and fracture surfaces were evaluated with a scanning electron microscope. The data were statistically analysed (SPSS 17.0) (p=0.05). Group RV-D exhibited the lowest bond strength value (5.42±6.6MPa). There was statistically no difference among RV-D, V2-D (13.78±8.8MPa) and VV-D (13.84±6.2MPa) groups (p>0.05). Group VV-E exhibited the highest bond strength value (24.76±8.8MPa). The type of tooth structure affected the shear bond strength of the porcelain laminate veneers to the 3 different types of tooth structures (enamel, dentine, and enamel-dentine complex). When dentine exposure is necessary during preparation, enough sound enamel must be protected as much as possible to maintain a good bonding; to obtain maximum bond strength, preparation margins should be on sound enamel. Copyright © 2012 Elsevier Ltd. All rights reserved.

Effect of ultrasonic tip and root-end filling material on bond strength.

PubMed

Vivan, Rodrigo Ricci; Guerreiro-Tanomaru, Juliane Maria; Bernardes, Ricardo Affonso; Reis, José Mauricio Santos Nunes; Hungaro Duarte, Marco Antonio; Tanomaru-Filho, Mário

2016-11-01

The objective of this study was to evaluate the bond strength of three root-end filling materials (MTAA-MTA Angelus, MTAS-experimental MTA Sealer, and ZOE- zinc oxide and eugenol cement) in retrograde preparations performed with different ultrasonic tips (CVD, Trinity, and Satelec). Ninety 2-mm root sections from single-rooted human teeth were used. The retrograde cavities were prepared by using the ultrasonic tips, coupled to a device for position standardization. The specimens were randomly divided into nine groups: CVD MTAA; CVD MTAS; CVD ZOE; Trinity MTAA; Trinity MTAS; Trinity ZOE; Satelec MTAA; Satelec MTAS; Satelec ZOE. Each resin disc/dentin/root-end filling material was placed in the machine to perform the push-out test. The specimens were examined in a stereomicroscope to evaluate the type of failure. Data were submitted to statistical analysis using ANOVA and Tukey tests (α = 0.05). The highest bond strength was observed for the CVD tip irrespective of the material used (P < 0.05). There was no significant difference for the Trinity TU-18 diamond and S12 Satelec tips (P > 0.05). MTAA and MTAS showed highest bond strength. The most common type of failure was adhesion between the filling material and dentin wall, except for ZOE, where mixed failure was predominant. The CVD tip favored higher bond strength of the root-end filling materials. MTA Angelus and experimental MTAS presented bond strength to dentin prepared with ultrasonic tips. Root-end preparation with the CVD tip positively influences the bond strength of root-end filling materials. MTA Angelus and experimental MTAS present bond strength to be used as root-end filling materials.

Effect of Various Laser Surface Treatments on Repair Shear Bond Strength of Aged Silorane-Based Composite

PubMed Central

Alizadeh Oskoee, Parnian; Savadi Oskoee, Siavash; Rikhtegaran, Sahand; Pournaghi-Azar, Fatemeh; Gholizadeh, Sarah; Aleyasin, Yasaman; Kasrae, Shahin

2017-01-01

Introduction: Successful repair of composite restorations depends on a strong bond between the old composite and the repair composite. This study sought to assess the repair shear bond strength of aged silorane-based composite following surface treatment with Nd:YAG, Er,Cr:YSGG and CO2 lasers. Methods: Seventy-six Filtek silorane composite cylinders were fabricated and aged by 2 months of water storage at 37°C. The samples were randomly divided into 4 groups (n=19) of no surface treatment (group 1) and surface treatment with Er,Cr:YSGG (group 2), Nd:YAG (group 3) and CO2 (group 4) lasers. The repair composite was applied and the shear bond strength was measured. The data were analyzed using one-way analysis of variance (ANOVA) and Tukey posthoc test. Prior to the application of the repair composite, 2 samples were randomly selected from each group and topographic changes on their surfaces following laser irradiation were studied using a scanning electron microscope (SEM). Seventeen other samples were also fabricated for assessment of cohesive strength of composite. Results: The highest and the lowest mean bond strength values were 8.99 MPa and 6.69 MPa for Er,Cr:YSGG and control groups, respectively. The difference in the repair bond strength was statistically significant between the Er,Cr:YSGG and other groups. Bond strength of the control, Nd:YAG and CO2 groups was not significantly different. The SEM micrographs revealed variable degrees of ablation and surface roughness in laser-treated groups. Conclusion: Surface treatment with Er,Cr:YSGG laser significantly increase the repair bond strength of aged silorane-based composite resin. PMID:29071025

Tooth surface treatment strategies for adhesive cementation

PubMed Central

2017-01-01

PURPOSE The aim of this study was to evaluate the effect of tooth surface pre-treatment steps on shear bond strength, which is essential for understanding the adhesive cementation process. MATERIALS AND METHODS Shear bond strengths of different cements with various tooth surface treatments (none, etching, priming, or etching and priming) on enamel and dentin of human teeth were measured using the Swiss shear test design. Three adhesives (Permaflo DC, Panavia F 2.0, and Panavia V5) and one self-adhesive cement (Panavia SA plus) were included in this study. The interface of the cement and the tooth surface with the different pre-treatments was analyzed using SEM. pH values of the cements and primers were measured. RESULTS The highest bond strength values for all cements were achieved with etching and primer on enamel (25.6 ± 5.3 - 32.3 ± 10.4 MPa). On dentin, etching and priming produced the highest bond strength values for all cements (8.6 ± 2.9 - 11.7 ± 3.5 MPa) except for Panavia V5, which achieved significantly higher bond strengths when pre-treated with primer only (15.3 ± 4.1 MPa). Shear bond strength values were correlated with the micro-retentive surface topography of enamel and the tag length on dentin except for Panavia V5, which revealed the highest bond strength with primer application only without etching, resulting in short but sturdy tags. CONCLUSION The highest bond strength can be achieved for Panavia F 2.0, Permaflo DC, and Panavia SA plus when the tooth substrate is previously etched and the respective primer is applied. The new cement Panavia V5 displayed low technique-sensitivity and attained significantly higher adhesion of all tested cements to dentin when only primer was applied. PMID:28435616

Effect of blood contamination on shear bond strength of orthodontic brackets and disinclusion buttons.

PubMed

Sfondrini, Maria Francesca; Gatti, Sara; Scribante, Andrea

2011-07-01

Our aim was to assess the effect of blood contamination on the shear bonding strength and sites of failure of orthodontic brackets and bondable buttons. We randomly divided 160 bovine permanent mandibular incisors into 8 groups of 20 specimens each. Both orthodontic brackets (Step brackets, Leone, Sesto Fiorentino, Italy) and bondable buttons (Flat orthodontic buttons, Leone, Sesto Fiorentino, Italy) were tested on four different enamel surfaces: dry; contamination with blood before priming; after priming; and before and after priming. Brackets and buttons were bonded to the teeth and subsequently tested using a Instron universal testing machine. Shear bonding strength and the rate of adhesive failures were recorded. Data were analysed using the analysis of variance (ANOVA), Scheffè tests, and the chi-square test. Uncontaminated enamel surfaces showed the highest bonding strengths for both brackets and buttons. When they were contaminated with blood, orthodontic brackets had significantly lower shear strengths than bondable buttons (P=0.0001). There were significant differences in sites of failure among the groups for the various enamel surfaces (P=0.001). Contamination of enamel by blood during bonding lowers the strength of the bond, more so with orthodontic brackets than with bondable buttons. Copyright © 2010 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Influence of Hot-Etching Surface Treatment on Zirconia/Resin Shear Bond Strength

PubMed Central

Lv, Pin; Yang, Xin; Jiang, Ting

2015-01-01

This study was designed to evaluate the effect of hot-etching surface treatment on the shear bond strength between zirconia ceramics and two commercial resin cements. Ceramic cylinders (120 units; length: 2.5 mm; diameter: 4.7 mm) were randomly divided into 12 groups (n = 10) according to different surface treatments (blank control; airborne-particle-abrasion; hot-etching) and different resin cements (Panavia F2.0; Superbond C and B) and whether or not a thermal cycling fatigue test (5°–55° for 5000 cycles) was performed. Flat enamel surfaces, mounted in acrylic resin, were bonded to the zirconia discs (diameter: 4.7 mm). All specimens were subjected to shear bond strength testing using a universal testing machine with a crosshead speed of 1 mm/min. All data were statistically analyzed using one-way analysis of variance and multiple-comparison least significant difference tests (α = 0.05). Hot-etching treatment produced higher bond strengths than the other treatment with both resin cements. The shear bond strength of all groups significantly decreased after the thermal cycling test; except for the hot-etching group that was cemented with Panavia F2.0 (p < 0.05). Surface treatment of zirconia with hot-etching solution enhanced the surface roughness and bond strength between the zirconia and the resin cement. PMID:28793699

Influence of preheating the bonding agent of a conventional three-step adhesive system and the light activated resin cement on dentin bond strength

PubMed Central

Holanda, Daniel Brandão Vilela; França, Fabiana Mantovani Gomes; do Amaral, Flávia Lucisano Botelho; Flório, Flávia Martão; Basting, Roberta Tarkany

2013-01-01

Aims: to evaluate the influence of preheating the bonding agent (Scotchbond Multipurpose Adhesive/3M ESPE) and the light-activated resin cement (RelyX Venner/3M ESPE) on dentin microtensile bond strength. Materials and Methods: The exposed flat dentin surface of 40 human third molars were randomly distributed into four groups for cementation (SR Adoro/Ivoclar Vivadent) (n = 10): G1-bond and resin cement, both at room temperature (22°C), G2-bond preheated to 58°C and cement at room temperature (22°C), G3-bond at room temperature (22°C) and the cement preheated to 58°C, G4-bond preheated to 58°C and cement preheated to 58°C. Sticks of dentin/block set measuring approximately 1 mm2 were obtained and used for the microtensile bond strength test. All sticks had their failure mode classified. Statistical analysis used: Factorial analysis of variance was applied, 2 × 2 (bond × cement) (P < 0.05). Results: Preheating the bonding agent (P = 0.8411) or the cement (P = 0.7155), yielded no significant difference. The interaction bond × cement was not significant (P = 0.9389). Conclusions: Preheating the bond and/or the light-activated resin cement did not influence dentin bond strength or fracture failure mode. PMID:24347889

Current-Assisted Diffusion Bonding of Extruded Ti-22Al-25Nb Alloy by Spark Plasma Sintering: Interfacial Microstructure and Mechanical Properties

NASA Astrophysics Data System (ADS)

Yang, Jianlei; Wang, Guofeng; Jiao, Xueyan; Gu, Yibin; Liu, Qing; Li, You

2018-05-01

Spark plasma sintering (SPS) technology was used to current-assisted bond extruded Ti-22Al-25Nb alloy. The effects of bonding temperature (920-980 °C) and bonding time (10-30 min) on the microstructure evolution and shear strength of this alloy were investigated systematically. The temperature distribution in the specimen during the current-assisted bonding process was also analyzed by numerical simulation. It is noted that the highest temperature was obtained at the bonding interface. As the bonding temperature and bonding time increased, the voids in the interface shrank increasingly until they vanished. A complete metallurgical bonding interface could be produced at 960 °C/20 min/10 MPa, exhibiting the highest shear strength of 269.3 MPa. In addition, the shear strength of the bonded specimen depended on its interfacial microstructure. With increased bonding temperature, the fracture mode transformed from the intergranular fracture at the bonding interface to the cleavage fracture in the substrate.

[The influences of crystallized compositions in the porcelain on bonding strength of titanium to porcelain].

PubMed

Mo, A; Wang, J; Liao, Y; Cen, Y; Shi, X

2001-12-01

Sufficient porcelain-titanium bond is a vital factor determining the clinical performance of titanium-porcelain restorations. The purpose of this study was to investigate the effects of self-preparation La-porcelain composition on the porcelain-titanium bonding strength and to compare with the Vita Titankeramik. The present study examines 5 different recipes of porcelain by weight%: SiO2, 12%-17%; LaO2, 7%-10%; Al2O3, 9%-14%; B2O3, 23%-31%; CaO, 6%-8%; K2O, 2%-3%; SrO, 2%-4%; Na2O, 1%-3%; SnO2, 8%-10%; ZrO2, 3%-5%; TiO2, 6%-8%. Specimens were tested in push type shear with a universal testing machine. Scanning electron microscopy (SEM) and electron probe microanalyzer (EPMA) were employed to reveal the microstructures and diffusion of elements in the interfacial regions between the porcelain coating and titanium to the bond strength when fired at 800 degrees C. The ratios of crystallized compositions had significant influences on the porcelain-titanium bond strength (P < 0.05). La-porcelain had the highest shear bond strength (37.76 MPa). The shear bond strength of the Vita Titankeramik to titanium was 20.18 MPa. The results of SEM revealed integrity of porcelain-titanium joints in La-porcelain and a greater amount of porosity in the interface of Vita Titankeramik to titanium. EPMA analysis demonstrated the aggregation of Si and Sn in the interfacial regions and their diffusion into the titanium. Chemical compositions of porcelain and ratios of crystallized compositions play the important role in the titanium porcelain bond. La-porcelain had the highest shear bond strength and good porcelain-titanium joints. La-porcelain is a new-style low fusing porcelain/titanium system.

The effect of different surface treatments on the bond strength of a gingiva-colored indirect composite veneering material to three implant framework materials.

PubMed

Koizuka, Mai; Komine, Futoshi; Blatz, Markus B; Fushiki, Ryosuke; Taguchi, Kohei; Matsumura, Hideo

2013-09-01

To evaluate and compare the shear-bond strength of a gingiva-colored indirect composite material to three different implant framework materials (zirconia ceramics, gold alloy, and titanium), and to investigate the effect of surface pretreatment by air-particle abrasion and four priming agents. A gingiva-colored indirect composite (Ceramage) was bonded to three framework materials (n = 80): commercially pure titanium (CP- Ti ), ADA (American Dental Association)-type 4 casting gold alloy (Type IV), and zirconia ceramics (Zirconia) with or without airborne-particle abrasion. Before bonding, the surface of the specimens was treated using no (control) or one of four priming agents: Alloy Primer (ALP), Estenia Opaque Primer (EOP), Metal Link Primer (MLP), and V-Primer (VPR). Shear-bond strength was determined after 24-h wet storage. Data were analyzed using Steel-Dwass for multiple comparisons, and Mann-Whitney U-test (P = 0.05). For both CP- Ti and Zirconia substrates, three groups, ALP, EOP, and MLP, showed significantly higher bond strengths (P < 0.05) than the other groups with or without airborne-particle abrasion. For Type IV substrates, significantly higher bond strengths were obtained in ALP and MLP groups (P < 0.01) compared with the other groups with airborne-particle abrasion. Application of priming agents containing specific phosphoric ester groups significantly enhances the bond strength of a gingiva-colored composite material to commercially pure titanium and zirconia frameworks. Combined use of a thione monomer with a phosphoric monomer enhances the bond strengths to airborne-particle abraded type IV gold alloy. © 2012 John Wiley & Sons A/S.

Comparison of shear bond strength relative to two testing devices.

PubMed

Pecora, Nikole; Yaman, Peter; Dennison, Joseph; Herrero, Alberto

2002-11-01

Dentin adhesives are characterized on the basis of their bond strength to dentin; however, great variation exists within the same material depending on the testing apparatus. To realistically compare bond strengths, the testing mechanisms must be the same. The purpose of this investigation was to use 2 testing devices to evaluate the shear bond strength of 3 single-bottle adhesives with their multistep counterparts. The occlusal surfaces of 120 freshly extracted third molars were ground to expose the dentin and polished with 600-grit silicon carbide paper. Three single-bottle, (Optibond Solo Plus, 3M Single Bond, and Excite) and 3 multistep adhesives (Optibond FL, 3M MultiPurpose Plus, and Syntac) were each used to bond a composite cylinder (made from a 2.379 +/-.001-mm diameter by 4-mm-high mold) of Tetric Ceram to 20 teeth. The specimens were stored in 100% humidity for 24 hours. The shear bond strength at failure was measured in kilograms and converted to megapascals for each material, using a knife (conventional method) and an Ultradent testing device on a universal testing machine (Instron) at a loading rate of 0.5 mm/min. A 2-way analysis of variance (ANOVA) test was performed comparing the 2 testing devices and the materials at P<.05. Where significant, a 1-way ANOVA test was conducted among the materials for each test group, and a Tukey multiple comparison test was used to determine significant differences among the materials tested (P<.05). An independent Student t test at P<.05 was used to determine significance between testing devices. The results showed that Optibond Solo Plus (26.85 +/- 8.76 MPa), Optibond FL (25.40 +/- 4.44 MPa), 3M Single Bond (28.12 +/- 5.01 MPa), and 3M MultiPurpose Plus (34.40 +/- 7.90 MPa) had significantly higher bond strengths when tested with the Ultradent testing device. The mean values for Excite (19.47 +/- 6.17 MPa) and Syntac (20.20 +/- 7.07 MPa) were also higher with the Ultradent testing device, but the difference was not significant. Within the limitations of this study, all bonding agents tested resulted in higher mean shear bond strengths when tested with the Ultradent testing device compared with the unrestricted knife. The single-step bonding agents exhibited mean bond strengths comparable to their multistep counterparts.

Evaluation of a new nano-filled restorative material for bonding orthodontic brackets.

PubMed

Bishara, Samir E; Ajlouni, Raed; Soliman, Manal M; Oonsombat, Charuphan; Laffoon, John F; Warren, John

2007-01-01

To compare the shear bond strength of a nano-hybrid restorative material, Grandio (Voco, Cuxhaven, Germany), to that of a traditional adhesive material (Transbond XT; 3M Unitek, Monrovia, CA, USA) when bonding orthodontic brackets. Forty teeth were randomly divided into 2 groups: 20 teeth were bonded with the Transbond adhesive system and the other 20 teeth with the Grandio restorative system, following manufacturer's instructions. Student t test was used to compare the shear bond strength of the 2 systems. Significance was predetermined at P 5 .05. The t test comparisons (t = 0.55) of the shear bond strength between the 2 adhesives indicated the absence of a significant (P = .585) difference. The mean shear bond strength for Grandio was 4.1 +/- 2.6 MPa and that for Transbond XT was 4.6 +/- 3.2 MPa. During debonding, 3 of 20 brackets (15%) bonded with Grandio failed without registering any force on the Zwick recording. None of the brackets bonded with Transbond XT had a similar failure mode. The newly introduced nano-filled composite materials can potentially be used to bond orthodontic brackets to teeth if its consistency can be more flowable to readily adhere to the bracket base.

Effect of hydrostatic pressure on regional bond strengths of compomers to dentine.

PubMed

Zheng, L; Pereira, P N; Somphone, P; Nikaido, T; Tagami, J

2000-09-01

The aim of this study was to evaluate the effect of hydrostatic pressure on the regional bond strengths of compomers to dentine. Thirty freshly extracted molars were ground flat to expose the dentine and randomly divided into two groups for bonding: no hydrostatic pressure and hydrostatic pressure of 15cm H(2)O. Xeno CF, Dyract AP and F 2000 were applied to dentine surfaces pretreated by the respective bonding systems following the manufactures' instructions, and then restored with Clearfil AP-X. After 24h storage in water, the teeth were sectioned into 0.7-mm thick slabs and visually divided into three regional subgroups: the region communicating with the pulp through dentinal tubules (pulp horn); the region between the pulp horns (center); and the region between the pulp horn and DEJ (periphery). The specimens were trimmed to a cross-sectional area of 1mm(2) and subjected to the micro-tensile bond test. The data were analyzed by one- and three-way ANOVA, and Fisher's PLSD (p<0.05). There were no significant regional differences of bond strengths for all the compomers tested (p>0.05). However, hydrostatic pressure significantly decreased the bond strength of F 2000 to all regions (p<0.05), while the bond strength of Dyract AP significantly decreased only at the pulp horn region (p<0.05). On the other hand, the bond strengths of Xeno CF seemed not to be affected by hydrostatic pressure (p>0.05). For Dyract AP and F 2000, the fracture modes were affected by hydrostatic pressure, while, for Xeno CF, there were no significant differences between the fracture modes with non- or positive hydrostatic pressure. Simulated pulpal pressure of 15cm H(2)O had a greater influence on the bond strengths of compomers to dentine than did dentine regions. Therefore, when measuring the bond strengths of compomers to dentine under the simulated in vivo conditions, the wetness of the dentine surface, as well as the intrinsic properties of each material should be seriously considered.

Casein Phosphopeptide-Amorphous Calcium Phosphate and Shear Bond Strength of Adhesives to Primary Teeth Enamel

PubMed Central

Farokh Gisovar, Elham; Hedayati, Nassim; Shadman, Niloofar; Shafiee, Leila

2015-01-01

Background: CPP-ACP (Phosphopeptide-Amorphous Calcium Phosphate) has an important role in caries prevention in pediatric patients. This study was done, because of the great use of CPP-ACP and the need for restoration for teeth treated with CPP-ACP as well as the importance of shear bond strength of adhesives in the success of restorations. Objectives: This study aimed to evaluate the effect of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) on shear bond strength of dental adhesives to enamel of primary teeth molars. Materials and Methods: This in vitro study was conducted on 180 extracted primary molars. They were randomly divided into 6 groups and each group was divided into 2 subgroups (treated with CPP-ACP and untreated). In subgroups with CPP-ACP, enamel was treated with CPP-ACP paste 1 h/d for 5 days. Types of adhesives that were evaluated in this study were Tetric N-Bond, AdheSE, AdheSE One F, single Bond 2, SE Bond, and Adper Prompt L-Pop. Shear bond strength was tested with a universal testing machine and mode of failure was evaluated under stereomicroscope. Data were analyzed by T test, 2-way analysis of variance (ANOVA), Tukey and Fisher exact test using SPSS18. P < 0.05 was considered as significance level. Results: Shear bond strengths of different adhesive systems to enamel of primary teeth treated and untreated with CPP-ACP showed no significant difference (P > 0.05). Mode of failure in all groups regardless of CPP-ACP administration was mainly adhesive type. Our results indicated that CPP-ACP did not affect shear bond strength of studied adhesives to primary teeth enamel. Conclusions: To have a successful and durable composite restoration, having a high strength bonding is essential. Considering the wide use of CPP-ACP in preventing tooth decay and the role of adhesive shear bond strength (SBS) in success of composite restoration, we conducted the present study to evaluate the effect of CPP-ACP on the SBS of adhesives to primary teeth enamel. PMID:25793113

Testing Bonds Between Brittle And Ductile Films

NASA Technical Reports Server (NTRS)

Wheeler, Donald R.; Ohsaki, Hiroyuki

1989-01-01

Simple uniaxial strain test devised to measure intrinsic shear strength. Brittle film deposited on ductile stubstrate film, and combination stretched until brittle film cracks, then separates from substrate. Dimensions of cracked segments related in known way to tensile strength of brittle film and shear strength of bond between two films. Despite approximations and limitations of technique, tests show it yields semiquantitative measures of bond strengths, independent of mechanical properties of substrates, with results reproducible with plus or minus 6 percent.

Effect of water-ageing on dentine bond strength and anti-biofilm activity of bonding agent containing new monomer dimethylaminododecyl methacrylate

PubMed Central

Zhang, Ke; Cheng, Lei; Wu, Eric J.; Weir, Michael D.; Bai, Yuxing; Xu, Hockin H. K.

2013-01-01

Objectives The objectives of this study were to develop bonding agent containing a new antibacterial monomer dimethylaminododecyl methacrylate (DMADDM) as well as nanoparticles of silver (NAg) and nanoparticles of amorphous calcium phosphate (NACP), and to investigate the effects of water-ageing for 6 months on dentine bond strength and anti-biofilm properties for the first time. Methods Four bonding agents were tested: Scotchbond Multi-Purpose (SBMP) Primer and Adhesive control; SBMP + 5% DMADDM; SBMP + 5% DMADDM + 0.1% NAg; and SBMP + 5% DMADDM + 0.1% NAg with 20% NACP in adhesive. Specimens were water-aged for 1 d and 6 months at 37 °C. Then the dentine shear bond strengths were measured. A dental plaque microcosm biofilm model was used to inoculate bacteria on water-aged specimens and to measure metabolic activity, colony-forming units (CFUs), and lactic acid production. Results Dentine bond strength showed a 35% loss in 6 months of water-ageing for SBMP control (mean ± sd; n = 10); in contrast, the new antibacterial bonding agents showed no strength loss. The DMADDM–NAg–NACP containing bonding agent imparted a strong antibacterial effect by greatly reducing biofilm viability, metabolic activity and acid production. The biofilm CFU was reduced by more than two orders of magnitude, compared to SBMP control. Furthermore, the DMADDM–NAg–NACP bonding agent exhibited a long-term antibacterial performance, with no significant difference between 1 d and 6 months (p > 0.1). Conclusions Incorporating DMADDM–NAg–NACP in bonding agent yielded potent and long-lasting antibacterial properties, and much stronger bond strength after 6 months of water-ageing than a commercial control. The new antibacterial bonding agent is promising to inhibit biofilms and caries at the margins. The method of DMADDM–NAg–NACP incorporation may have a wide applicability to other adhesives, cements and composites. PMID:23583528

Bond efficacy and interface morphology of self-etching adhesives to ground enamel.

PubMed

Abdalla, Ali I; El Zohairy, Ahmed A; Abdel Mohsen, Mohamed M; Feilzer, Albert J

2010-02-01

This study compared the microshear bond strengths to ground enamel of three one-step self-etching adhesive systems, a self-etching primer system and an etch-and-rinse adhesive system. Three self-etching adhesives, Futurabond DC (Voco), Clearfil S Tri Bond (Kuraray) and Hybrid bond (Sun-Medical), a self-etching primer, Clearfil SE Bond (Kuraray), and an etch-and-rinse system, Admira Bond (Voco), were selected. Thirty human molars were used. The root of each tooth was removed and the crown was sectioned into halves. The convex enamel surfaces were reduced by polishing on silicone paper to prepare a flat surface. The bonding systems were applied on this surface. Prior to adhesive curing, a hollow cylinder (2.0 mm height/0.75 mm internal diameter) was placed on the treated surfaces. A resin composite was then inserted into the tube and cured. After water storage for 24 h, the tube was removed and shear bond strength was determined in a universal testing machine at a crosshead speed of 0.5 mm/min. The results were analyzed with ANOVA and the Tukey.-Kramer test at a 59 degrees confidence level. The enamel of five additional teeth was ground, and the etching component of each adhesive was applied and removed with absolute ethanol instead of being light cured. These teeth and selected fractured surfaces were examined by SEM. Adhesion to ground enamel of the Futurabond DC (25 +/- 3.5 MPa) and Clearfil SE Bond (23 +/- 2.9 MPa) self-etching systems was not significantly different from the etch-and-rinse system Admira Bond (27 +/- 2.3 MPa). The two self-etching adhesives Clearfil S Tri bond and Hybrid Bond demonstrated significantly lower bond strengths (14 +/- 1.4 MPa; 11 +/- 1.9 MPa) with no significant differences between them (p < 0.05). Bond strengths to ground enamel of self-etching adhesive systems are dependent on the type of adhesive system. Some of the new adhesive systems showed bond strength values comparable to that of etch-and-rinse systems. There was no correlation between bond strength and morphological changes in enamel.

Immediate vs delayed repair bond strength of a nanohybrid resin composite.

PubMed

El-Askary, Farid S; El-Banna, Ahmed H; van Noort, Richard

2012-06-01

To evaluate both the immediate and water-stored repair tensile bond strength (TBS) of a nanohybrid resin composite using different bonding protocols. One hundred sixty half hourglass-shaped slabs were prepared. Eighty half-slabs were wet ground immediately after light curing using high-speed abrasive burs, while the other half-slabs were stored in water for one month (delayed) and then wet ground for repair. Each set of the 80 repaired slabs was split into two groups to be tested for TBS after 24 h or 1 month of water storage. For all repaired slabs, either immediate or delayed, four bonding procedures were used involving wet and dry bonding with a 3-step etch-and-rinse adhesive with or without silane pretreatment. TBS tests were performed at a crosshead speed of 0.5 mm/min. To determine the cohesive strength of the resin composite itself, which served as the reference, additional whole slabs were prepared and tested in tension after a 24-h (n = 10) and a 1-month storage period (n = 10). Failure modes were evaluated using a stereomicroscope at 40X magnification. Three-way ANOVA was run to test the effect of water storage, testing time, bonding protocols, and their interactions on the repair TBS, which was given as a percentage of the reference values. For the immediate repair groups, the repair TBS ranged from 40% to 61.9% after 24-h storage and from 26% to 53.1% after 1-month water storage compared to the TBS of the whole slabs. For the delayed repair group, the repaired TBS ranged from 47.2% to 63.6% for the 24-h repairs and from 32.2% to 44.2% for the test groups stored in water for 1 month. Three-way ANOVA revealed that water storage had no significant effect on the repair TBS (p = 0.619). Both testing time and bonding protocols had a significant effect on the repair TBS (p = 0.001). The interactions between the independent variables (water storage, testing time, and bonding protocols) had no significant effect (p = 0.067). The repair bond strength was consistently and highly significantly less than the cohesive strength of the composite. A delay of 1 month before carrying out the repair had no effect on the bond strength, irrespective of the bonding procedure used. Silane treatment did not improve the repair bond strength. In all instances, except for the immediate wet bonding plus silane procedure and delayed dry bonding, the bond strength of the repairs significantly dropped after 1 month of storage in water.

Effect of air-drying time of single-application self-etch adhesives on dentin bond strength.

PubMed

Chiba, Yasushi; Yamaguchi, Kanako; Miyazaki, Masashi; Tsubota, Keishi; Takamizawa, Toshiki; Moore, B Keith

2006-01-01

This study examined the effect of air-drying time of adhesives on the dentin bond strength of several single-application self-etch adhesive systems. The adhesive/resin composite combinations used were: Adper Prompt L-Pop/Filtek Z250 (AP), Clearfil Tri-S Bond/Clearfil AP-X (CT), Fluoro Bond Shake One/Beautifil (FB), G-Bond/Gradia Direct (GB) and One-Up Bond F Plus/Palfique Estelite (OF). Bovine mandibular incisors were mounted in self-curing resin and wet ground with #600 SiC to expose labial dentin. Adhesives were applied according to each manufacturer's instructions followed by air-drying time for 0 (without air-drying), 5 and 10 seconds. After light irradiation of the adhesives, the resin composites were condensed into a mold (phi4x2 mm) and polymerized. Ten samples per test group were stored in 37 degrees C distilled water for 24 hours; they were then shear tested at a crosshead speed of 1.0 mm/minute. One-way ANOVA followed by Tukey's HSD tests (alpha = 0.05) were done. FE-SEM observations of the resin/dentin interface were also conducted. Dentin bond strength varied with the different air drying times and ranged from 5.8 +/- 2.4 to 13.9 +/- 2.8 MPa for AP, 4.9 +/- 1.5 to 17.1 +/- 2.3 MPa for CT, 7.9 +/- 2.8 to 13.8 +/- 2.4 MPa for FB, 3.7 +/- 1.4 to 13.4 +/- 1.2 MPa for GB and 4.6 +/- 2.1 to 13.7 +/- 2.6 MPa for OF. With longer air drying of adhesives, no significant changes in bond strengths were found for the systems used except for OF. Significantly lower bond strengths were obtained for the 10-second air-drying group for OF. From FE-SEM observations, gaps between the cured adhesive and resin composites were observed for the specimens without the air drying of adhesives except for OF. The data suggests that, with four of the single-application self-etch adhesive systems, air drying is essential to obtain adequate dentin bond strengths, but increased drying time does not significantly influence bond strength. For the other system studied, the bond strength of the non-air dried group was not significantly different from the five second drying time, but prolonged drying was very detrimental to bond strength. For all five of the systems studied, a five-second air-drying time appeared to be appropriate.

Dentin pretreatment and adhesive temperature as affecting factors on bond strength of a universal adhesive system.

PubMed

Sutil, Bruna Gabrielle da Silva; Susin, Alexandre Henrique

2017-01-01

To evaluate the effects of dentin pretreatment and temperature on the bond strength of a universal adhesive system to dentin. Ninety-six extracted non-carious human third molars were randomly divided into 12 groups (n=8) according to Scotchbond Universal Adhesive (SbU) applied in self-etch (SE) and etch-and-rinse (ER) mode, adhesive temperature (20°C or 37°C) and sodium bicarbonate or aluminum oxide air abrasion. After composite build up, bonded sticks with cross-sectional area of 1 mm2 were obtained to evaluate the microtensile bond strength (μTBS). The specimens were tested at a crosshead speed of 0.5 mm/min on a testing machine until failure. Fractured specimens were analyzed under stereomicroscope to determine the failure patterns in adhesive, cohesive (dentin or resin) and mixed fractures. The microtensile bond strength data was analyzed using two-way ANOVA and Tukey's test (α=5%). Interaction between treatment and temperature was statistically significant for SbU applied in self-etch technique. Both dentin treatments showed higher bond strength for ER mode, regardless of adhesive temperature. When compared to control group, sodium bicarbonate increased bond strength of SbU in SE technique. Adhesive temperature did not significantly affect the μTBS of tested groups. Predominantly, adhesive failure was observed for all groups. Dentin surface treatment with sodium bicarbonate air abrasion improves bond strength of SbU, irrespective of adhesive application mode, which makes this approach an alternative to increase adhesive performance of Scotchbond Universal Adhesive to dentin.

Dentin pretreatment and adhesive temperature as affecting factors on bond strength of a universal adhesive system

PubMed Central

Sutil, Bruna Gabrielle da Silva; Susin, Alexandre Henrique

2017-01-01

Abstract Objectives: To evaluate the effects of dentin pretreatment and temperature on the bond strength of a universal adhesive system to dentin. Material and Methods: Ninety-six extracted non-carious human third molars were randomly divided into 12 groups (n=8) according to Scotchbond Universal Adhesive (SbU) applied in self-etch (SE) and etch-and-rinse (ER) mode, adhesive temperature (20°C or 37°C) and sodium bicarbonate or aluminum oxide air abrasion. After composite build up, bonded sticks with cross-sectional area of 1 mm2 were obtained to evaluate the microtensile bond strength (μTBS). The specimens were tested at a crosshead speed of 0.5 mm/min on a testing machine until failure. Fractured specimens were analyzed under stereomicroscope to determine the failure patterns in adhesive, cohesive (dentin or resin) and mixed fractures. The microtensile bond strength data was analyzed using two-way ANOVA and Tukey's test (α=5%). Results: Interaction between treatment and temperature was statistically significant for SbU applied in self-etch technique. Both dentin treatments showed higher bond strength for ER mode, regardless of adhesive temperature. When compared to control group, sodium bicarbonate increased bond strength of SbU in SE technique. Adhesive temperature did not significantly affect the μTBS of tested groups. Predominantly, adhesive failure was observed for all groups. Conclusions: Dentin surface treatment with sodium bicarbonate air abrasion improves bond strength of SbU, irrespective of adhesive application mode, which makes this approach an alternative to increase adhesive performance of Scotchbond Universal Adhesive to dentin. PMID:29069151

Influence of nano-structured alumina coating on shear bond strength between Y-TZP ceramic and various dual-cured resin cements.

PubMed

Lee, Jung-Jin; Choi, Jung-Yun; Seo, Jae-Min

2017-04-01

The purpose of this study was to evaluate the effect of nano-structured alumina surface coating on shear bond strength between Y-TZP ceramic and various dual-cured resin cements. A total of 90 disk-shaped zirconia specimens (HASS CO., Gangneung, Korea) were divided into three groups by surface treatment method: (1) airborne particle abrasion, (2) tribochemicalsilica coating, and (3) nano-structured alumina coating. Each group was categorized into three subgroups of ten specimens and bonded with three different types of dual-cured resin cements. After thermocycling, shear bond strength was measured and failure modes were observed through FE-SEM. Two-way ANOVA and the Tukey's HSD test were performed to determine the effects of surface treatment method and type of cement on bond strength ( P <.05). To confirm the correlation of surface treatment and failure mode, the Chi-square test was used. Groups treated with the nanostructured alumina coating showed significantly higher shear bond strength compared to other groups treated with airborne particle abrasion or tribochemical silica coating. Clearfil SA Luting showed a significantly higher shear bond strength compared to RelyX ARC and RelyX Unicem. The cohesive failure mode was observed to be dominant in the groups treated with nano-structured alumina coating, while the adhesive failure mode was prevalent in the groups treated with either airborne particle abrasion or tribochemical silica coating. Nano-structured alumina coating is an effective zirconia surface treatment method for enhancing the bond strength between Y-TZP ceramic and various dual-cured resin cements.

Residual Tensile Strength and Bond Properties of GFRP Bars after Exposure to Elevated Temperatures.

PubMed

Ellis, Devon S; Tabatabai, Habib; Nabizadeh, Azam

2018-02-27

The use of fiber reinforced polymer (FRP) bars in reinforced concrete members enhances corrosion resistance when compared to traditional steel reinforcing bars. Although there is ample research available on the behavior of FRP bars and concrete members reinforced with FRP bars under elevated temperatures (due to fire), there is little published information available on their post-fire residual load capacity. This paper reports residual tensile strength, modulus of elasticity, and bond strength (to concrete) of glass fiber reinforced polymer (GFRP) bars after exposure to elevated temperatures of up to 400 °C and subsequent cooling to an ambient temperature. The results showed that the residual strength generally decreases with increasing temperature exposure. However, as much as 83% of the original tensile strength and 27% of the original bond strength was retained after the specimens were heated to 400 °C and then cooled to ambient temperature. The residual bond strength is a critical parameter in post-fire strength assessments of GFRP-reinforced concrete members.

Residual Tensile Strength and Bond Properties of GFRP Bars after Exposure to Elevated Temperatures

PubMed Central

Ellis, Devon S.

2018-01-01

The use of fiber reinforced polymer (FRP) bars in reinforced concrete members enhances corrosion resistance when compared to traditional steel reinforcing bars. Although there is ample research available on the behavior of FRP bars and concrete members reinforced with FRP bars under elevated temperatures (due to fire), there is little published information available on their post-fire residual load capacity. This paper reports residual tensile strength, modulus of elasticity, and bond strength (to concrete) of glass fiber reinforced polymer (GFRP) bars after exposure to elevated temperatures of up to 400 °C and subsequent cooling to an ambient temperature. The results showed that the residual strength generally decreases with increasing temperature exposure. However, as much as 83% of the original tensile strength and 27% of the original bond strength was retained after the specimens were heated to 400 °C and then cooled to ambient temperature. The residual bond strength is a critical parameter in post-fire strength assessments of GFRP-reinforced concrete members. PMID:29495489

A Novel Process for Joining Ti Alloy and Al Alloy using Two-Stage Sintering Powder Metallurgy

NASA Astrophysics Data System (ADS)

Long, Luping; Liu, Wensheng; Ma, Yunzhu; Wu, Lei; Liu, Chao

2018-04-01

The major challenges for conventional diffusion bonding of joining Ti alloy and Al alloy are the undesirable interfacial reaction, low matrixes and joint strength. To avoid the problem in diffusion bonding, a novel two-stage sintering powder metallurgy process is developed. In the present work, the interface characterization and joint performance of the bonds obtained by powder metallurgy bonding are investigated and are compared with the diffusion bonded Ti/Al joints obtained with the same and the optimized process parameters. The results show that no intermetallic compound is visible in the Ti/Al joint obtained by powder metallurgy bonding, while a new layer formed at the joint diffusion bonded with the same parameters. The maximum tensile strength of joint obtained by diffusion bonding is 58 MPa, while a higher tensile strength reaching 111 MPa for a bond made by powder metallurgy bonding. Brittle fractures occur at all the bonds. It is shown that the powder metallurgy bonding of Ti/Al is better than diffusion bonding. The results of this study should benefit the bonding quality.

Collaboration of polymer composite reinforcement and cement concrete

NASA Astrophysics Data System (ADS)

Khozin, V. G.; Gizdatullin, A. R.

2018-04-01

The results of experimental study of bond strength of cement concrete of different types with fiber reinforcing polymer (FRP) bars are reported. The reinforcing bars were manufactured of glass fibers and had a rebar with different types of the surface relief formed by winding a thin strip impregnated with a binder or by “sanding”. The pullout tests were carried out simultaneously for the steel reinforcing ribbed bars A400. The impact of friction, adhesion and mechanical bond on the strength of bonds between FRP and concrete was studied. The influence of the concrete strength and different operation factors on the bond strength of concrete was evaluated.

Effect of metal primers on bond strength of resin cements to base metals.

PubMed

Fonseca, Renata Garcia; de Almeida, Juliana Gomes dos Santos Paes; Haneda, Isabella Gagliardi; Adabo, Gelson Luis

2009-04-01

A strong and durable bond between a metal framework and a resin-based luting agent is desired. Metal primers have been shown to be very effective on noble alloys. However, there is insufficient information about their effect on base metals. The purpose of this study was to evaluate the effect of metal primers on the shear bond strength of resin cements to base metals. A total of 160 cast commercially pure titanium (CP Ti) and NiCr alloy (VeraBond II) disks were embedded in a polyvinyl chloride ring, and their surfaces were smoothed with silicon carbide papers (320, 400, and 600 grit) and airborne-particle abraded with 50-mum aluminum oxide. Specimens of each metal were divided into 4 groups (n=20), which received one of the following luting techniques: (1) Panavia F, (2) Alloy Primer plus Panavia F, (3) Bistite II DC, or (4) Metaltite plus Bistite II DC. Forty minutes after preparation, all specimens were stored in distilled water at 37 degrees C for 24 hours and then thermal cycled (1000 cycles, 5-55 degrees C). After thermal cycling, the specimens were stored in 37 degrees C distilled water for an additional 24 hours or 6 months before being tested in shear mode. Data (MPa) were analyzed using 3-way ANOVA and the post hoc Tukey test (alpha=.05). Each specimen was examined under an optical microscope (x30), and the failure mode was classified as adhesive, cohesive, or a combination of these. The only significant difference between the Panavia F and Alloy Primer plus Panavia F groups occurred in the NiCr alloy at 24 hours, at which point Panavia F demonstrated superior bond strength compared to Alloy Primer plus Panavia F (P<.001). The Bistite II DC and Metaltite plus Bistite II DC groups were not significantly different. The Bistite II DC and Metaltite plus Bistite II DC groups demonstrated significantly lower bond strength to CP Ti (P<.001) than the Panavia F and Alloy Primer plus Panavia F groups, and significantly lower bond strength to NiCr alloy (P<.001) than Panavia F. The Panavia F (P<.01) and Alloy Primer plus Panavia F groups' bond strength to titanium presented a significant increase (P<.001) in shear bond strength at 6 months. In general, the groups exhibited higher shear bond strength to CP Ti than to NiCr alloy (P<.01). The failure mode was 100% adhesive for all groups. The metal primers did not promote an increase in adhesive bonding of resin cements to NiCr alloy and to CP Ti. Water storage had no adverse effect on the shear bond strength of the groups. The shear bond strengths to titanium were significantly higher than those to the NiCr alloy.

Bond Strength of Composite CFRP Reinforcing Bars in Timber

PubMed Central

Corradi, Marco; Righetti, Luca; Borri, Antonio

2015-01-01

The use of near-surface mounted (NSM) fibre-reinforced polymer (FRP) bars is an interesting method for increasing the shear and flexural strength of existing timber members. This article examines the behaviour of carbon FRP (CFRP) bars in timber under direct pull-out conditions. The objective of this experimental program is to investigate the bond strength between composite bars and timber: bars were epoxied into small notches made into chestnut and fir wood members using a commercially-available epoxy system. Bonded lengths varied from 150 to 300 mm. Failure modes, stress and strain distributions and the bond strength of CFRP bars have been evaluated and discussed. The pull-out capacity in NSM CFRP bars at the onset of debonding increased with bonded length up to a length of 250 mm. While CFRP bar’s pull-out was achieved only for specimens with bonded lengths of 150 and 200 mm, bar tensile failure was mainly recorded for bonded lengths of 250 and 300 mm. PMID:28793423

[Comparative study of 4 types of luting cements on shear bond strength of Zirconia ceramics to dentin].

PubMed

Yin, Bao-di; Zhang, Xian-fang; Zheng, Hu; Han, Dong-wei

2010-04-01

To investigate the adequate luting cements for zirconia ceramics to dentin. Blocks of sintered zirconia ceramics were randomly divided into 4 groups with 8 slices in each. After saliva immersion,airborne-particle abraded ceramic specimens were cleaned with phosphoric acid gel(containing 35% phosphoric acid) and then bonded to dentin with these four kinds of luting cements. After preserved in 37 degrees centigrade distilled water for 24 hours, the shear bonding strength of these specimens was tested and the data was analyzed with SPSS12.0 software package. The Multilink Automix could attain the highest shear bonding strength and the 3M RelyXTM Unicem AplicapTM could attain higher shear bonding strength, which were both significantly higher than in the Tokuso Ionomer and Shofu Polycarboxylate Cement groups(P<0.05). Total etching resin luting cement is an ideal option to the bonding of zirconia ceramics and can provide a strong bonding.

The effect of remin pro and MI paste plus on bleached enamel surface roughness.

PubMed

Ahmad Akhoundi, Mohammad Sadegh; Aghajani, Farzaneh; Chalipa, Javad; Sadrhaghighi, Amir Hooman

2014-03-01

Increased number of adult patients requesting orthodontic treatment result in bonding bracket to ceramic restorations more than before. The aim of this study was to evaluate and compare the shear bond strength of orthodontic brackets bonded to two types of ceramic bases with conventional orthodontic bonding resin and a new nano-filled composite resin. Twenty four feldespathic porcelain and 24 lithium disilicate ceramic disks were fabricated. All of the samples were conditioned by sandblasting, hydrofluoric acid and silane. Maxillary incisor metal brackets were bonded to half of the disks in each group by conventional orthodontic bonding resin and the other half bonded with a nano-filled composite. The samples then were thermocycled for 2000 cycle between 5-55° C. Shear bond strength was measured and the mode of failure was examined. Randomly selected samples were also evaluated by SEM. The lowest bond strength value was found infeldespathic ceramic bonded by nano-filled composite (p<0.05). There was not any statistically significant difference between other groups regarding bond strength. The mode of failure in the all groups except group 1 was cohesive and porcelain damages were detected. Since less damages to feldspathic porcelain was observed when the nano-filled composite was used to bond brackets, the use of nano-filled composite resins can be suggested for bonding brackets to feldspathic porcelain restorations.

The Effect of Remin Pro and MI Paste Plus on Bleached Enamel Surface Roughness

PubMed Central

Ahmad Akhoundi, Mohammad Sadegh; Aghajani, Farzaneh; Chalipa, Javad; Sadrhaghighi, Amir Hooman

2014-01-01

Objective Increased number of adult patients requesting orthodontic treatment result in bonding bracket to ceramic restorations more than before. The aim of this study was to evaluate and compare the shear bond strength of orthodontic brackets bonded to two types of ceramic bases with conventional orthodontic bonding resin and a new nano-filled composite resin. Materials and Methods: Twenty four feldespathic porcelain and 24 lithium disilicate ceramic disks were fabricated. All of the samples were conditioned by sandblasting, hydrofluoric acid and silane. Maxillary incisor metal brackets were bonded to half of the disks in each group by conventional orthodontic bonding resin and the other half bonded with a nano-filled composite. The samples then were thermocycled for 2000 cycle between 5–55° C. Shear bond strength was measured and the mode of failure was examined. Randomly selected samples were also evaluated by SEM. Results: The lowest bond strength value was found infeldespathic ceramic bonded by nano-filled composite (p<0.05). There was not any statistically significant difference between other groups regarding bond strength. The mode of failure in the all groups except group 1 was cohesive and porcelain damages were detected. Conclusion: Since less damages to feldspathic porcelain was observed when the nano-filled composite was used to bond brackets, the use of nano-filled composite resins can be suggested for bonding brackets to feldspathic porcelain restorations. PMID:24910698

Improved orthodontic bonding to silver amalgam. Part 2. Lathe-cut, admixed, and spherical amalgams with different intermediate resins.

PubMed

Büyükyilmaz, T; Zachrisson, B U

1998-08-01

Flat rectangular tabs (n = 270) prepared from spherical (Tytin), admixed (Dispersalloy) or lathe-cut amalgam (ANA 2000) were subjected to aluminum oxide sandblasting with either 50-mu or 90-mu abrasive powder. Mandibular incisor edgewise brackets were bonded to these tabs. An intermediate resin was used, either All-Bond 2 Primers A + B or a 4-META product--Amalgambond Plus (AP) or Reliance Metal Primer (RMP)--followed by Concise. All specimens were stored in water at 37 degrees C for 24 hours and thermocycled 1000 times from 5 degrees C to 55 degrees C and back before tensile bond strength testing. The bond strength of Concise to etched enamel of extracted, caries-free premolars was used as a control. Bond failure sites were classified using a modified adhesive remnant index (ARI) system. Results were expressed as mean bond strength with SD, and as a function relating the probability of bond failure to stress by means of Weibull analysis. Mean tensile bond strength in the experimental groups ranged from 2.9 to 11.0 MPa--significantly weaker than the control sample (16.0 MPa). Bond failure invariably occurred at the amalgam/adhesive interface. The strongest bonds were created to the spherical and lathe-cut amalgams (range 6.8 to 11.0 MPa). Bonds to the spherical amalgam were probably more reliable. The intermediate application of the 4-META resins AP and RMP generally created significantly stronger bonds to all three basic types of amalgam products than the bonds obtained with the All-Bond 2 primers. The effect of abrasive-particle size on bond strength to different amalgam surfaces was not usually significant (p > 0.05). The implications of these findings are discussed in relationship to clinical experience bonding orthodontic attachments to large amalgam restorations in posterior teeth.

Influence of intraoral temperature and relative humidity on the dentin bond strength: an in situ study.

PubMed

Saraiva, Letícia O; Aguiar, Thaiane R; Costa, Leonardo; Cavalcanti, Andrea N; Giannini, Marcelo; Mathias, Paula

2015-01-01

The effect of the intraoral environment during adhesive restorative procedures remains a concern, especially in the absence of rubber dam isolation. To evaluate the temperature and relative humidity (RH) at anterior and posterior intraoral sites and their effects on the dentin bond strength of two-step etch-and-rinse adhesive systems. Sixty human molars were assigned to six groups according to the adhesive systems (Adper Single Bond Plus and One Step Plus) and intraoral sites (incisor and molar sites). The room condition was used as a control group. Dentin fragments were individually placed in custom-made acetate trays and direct composite restorations were performed. The intraoral temperature and RH were recorded during adhesive procedures. Then, specimens were removed from the acetate trays and sectioned to obtain multiple beams for the microtensile bond strength test. In addition, the adhesive interface morphology was evaluated through scanning electron microscopy. Intraoral conditions were statistically analyzed by paired Students' t-tests and the bond strength data by two-way analysis of variance and Tukey test (α = 0.05). The posterior intraoral site showed a significant increase in the temperature and RH when compared with the anterior site. However, both intraoral sites revealed higher temperatures and RH than the room condition. In regards to the adhesive systems, the intraoral environment did not affect the bond strength, and the One Step Plus system showed the highest bond strength means. Despite the fact that remarkable changes in the intraoral conditions were observed for both anterior and posterior sites, the intraoral environment was not able to compromise the immediate dentin bond strength. Some conditions of intraoral temperature and relative humidity may not impair the dentin bond strength of two-step etch-and-rinse adhesive systems. Thus, an adequate relative isolation seems to be a good alternative under the specific clinical conditions in which rubber dam isolation is either impossible or very difficult to perform. © 2014 Wiley Periodicals, Inc.

Effect of 830 nm Diode Laser Irradiation of Root Canal on Bond Strength of Metal and Fiber Post.

PubMed

Strefezza, Claudia; Amaral, Marcello Magri; Quinto, José; Gouw-Soares, Sheila Cynthia; Zamataro, Claudia Bianchi; Zezell, Denise Maria

2018-05-16

The correct selections of the cementing agent, the endodontic post material and placement protocol are critical to provide an increased longevity of the teeth that went through endodontic treatment. The irradiation with diode laser before post cementation, can promote an antimicrobial effect. However, there is a lack of information about the effect of 830 nm diode laser on the post bond strength. This study analyzed the effect of dentin root canal irradiation with high-intensity diode laser, at 830 nm, operating in continuous or pulsed mode, on the retention of metal or fiber posts, cemented with self-etching resinous composite (Panavia F) and zinc phosphate cement (ZnPO 4 ). Human roots were irradiated with diode laser (continuous and pulsed mode). The fiber posts were luted with Panavia F and the metal posts with Panavia F or ZnPO 4 cement. Specimens were sectioned into three sections (cervical, middle, and apical). The bond strength was measured by a push-out mechanical analysis. For the statistical analysis, a three-way ANOVA test was applied following a Tukey's pairwise comparison with a significance level of p = 0.05. The irradiated groups presented higher bond strength compared with nonirradiated group (p < 0.05), and the cervical and middle thirds presented higher on bond strength than the apical. The association of metal post and Panavia F presented higher bond strength when irradiated on continuous mode (p < 0.05). Fiber post and Panavia F presented higher bond strength associated to pulsed mode. The mode seems not to make a significant difference. These results corroborate the importance of the post bond to dentin and root canal debris removal to increase the tooth longevity. It was shown that the dentin to post bond strength were enhanced by the diode laser irradiation either on continuous or pulsed modes.

Tensile bond strength of filled and unfilled adhesives to dentin.

PubMed

Braga, R R; Cesar, P F; Gonzaga, C C

2000-04-01

To determine the tensile bond strength of three filled and two unfilled adhesives applied to bovine dentin. Fragments of the labial dentin of bovine incisors were embedded in PVC cylinders with self-cure acrylic resin, and ground flat using 200 grit and 600 grit sandpaper. The following adhesive systems were tested (n=10): Prime & Bond NT, Prime & Bond NT dual cure, Prime & Bond 2.1, OptiBond Solo and Single Bond. A 3 mm-diameter bonding surface was delimited using a perforated adhesive tape. After etching with 37% phosphoric acid and adhesive application, a resin-based composite truncated cone (TPH, shade A3) was built. Tensile test was performed after 24 hrs storage in distilled water at 37 degrees C. Failure mode was accessed using a x10 magnification stereomicroscope. Weibull statistical analysis revealed significant differences in the characteristic strength between Single Bond and Prime & Bond NT dual cure, and between Single Bond and Prime & Bond 2.1. The Weibull parameter (m) was statistically similar among the five groups. Single Bond and Prime & Bond NT showed areas of dentin cohesive failure in most of the specimens. For OptiBond Solo, Prime & Bond NT dual cure and Prime & Bond 2.1 failure was predominantly adhesive.

Effect of nano-SiO{sub 2} particles and curing time on development of fiber-matrix bond properties and microstructure of ultra-high strength concrete

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, Zemei; Department of Civil, Architectural and Environmental Engineering, Missouri University of Science and Technology, Rolla 65409, MO; Khayat, Kamal Henri, E-mail: khayatk@mst.edu

Bond properties between fibers and cementitious matrix have significant effect on the mechanical behavior of composite materials. In this study, the development of steel fiber-matrix interfacial bond properties in ultra-high strength concrete (UHSC) proportioned with nano-SiO{sub 2} varying between 0 and 2%, by mass of cementitious materials, was investigated. A statistical model relating either bond strength or pullout energy to curing time and nano-SiO{sub 2} content was proposed by using the response surface methodology. Mercury intrusion porosimetry (MIP) and backscatter scanning electron microscopy (BSEM) were used to characterize the microstructure of the matrix and the fiber-matrix interface, respectively. Micro-hardness aroundmore » the embedded fiber and hydration products of the matrix were evaluated as well. Test results indicated that the optimal nano-SiO{sub 2} dosage was 1% in terms of the bond properties and the microstructure. The proposed quadratic model efficiently predicted the bond strength and pullout energy with consideration of curing time and nano-SiO{sub 2} content. The improvement in bond properties associated with nano-silica was correlated with denser matrix and/or interface and stronger bond and greater strength of hydration products based on microstructural analysis.« less

In vitro analysis of shear bond strength and adhesive remnant index of different metal brackets

PubMed Central

Henkin, Fernanda de Souza; de Macêdo, Érika de Oliveira Dias; Santos, Karoline da Silva; Schwarzbach, Marília; Samuel, Susana Maria Werner; Mundstock, Karina Santos

2016-01-01

ABSTRACT Introduction: There is a great variety of orthodontic brackets in the Brazilian market, and constantly evaluating them is critical for professionals to know their properties, so as to be able to choose which product best suits their clinical practice. Objectives: To evaluate the bond strength and the adhesive remnant index (ARI) of different brands of metal brackets. Material and Methods: A total of 105 bovine incisors were used, and brackets of different brands were bonded to teeth. Seven different bracket brands were tested (MorelliTM, American OrthodonticsTM, TP OrthodonticsTM, Abzil-3MTM, OrthometricTM, TecnidentTM and UNIDENTM). Twenty-four hours after bonding, shear bond strength test was performed; and after debonding, the ARI was determined by using an optical microscope at a 10-fold increase. Results: Mean shear bond strength values ranged from 3.845 ± 3.997 (MorelliTM) to 9.871 ± 5.106 MPa (TecnidentTM). The majority of the ARI index scores was 0 and 1. Conclusion: Among the evaluated brackets, the one with the lowest mean shear bond strength values was MorelliTM. General evaluation of groups indicated that a greater number of bond failure occurred at the enamel/adhesive interface. PMID:28125142

Rapid bonding enhancement by auxiliary ultrasonic actuation for the fabrication of cyclic olefin copolymer (COC) microfluidic devices

NASA Astrophysics Data System (ADS)

Yu, H.; Tor, S. B.; Loh, N. H.

2014-11-01

Thermal compression bonding is a straightforward, inexpensive and widely used method for enclosing open microchannels in thermoplastic microfluidic devices. It is advantageous over adhesive, solvent and grafting bonding methods in retaining material homogeneity. However, the trade-off between high bond strength and low microchannel deformation is always a crucial consideration in thermal compression bonding. In this study, an effective method for improving bond strength while retaining the microchannel integrity with negligible distortion is proposed and analyzed. Longitudinal ultrasonic actuation was applied to the preheated cyclic olefin copolymer (COC) substrates to achieve accelerated and enhanced bonding with an ultrasonic welding system. Intimate contact between the bonding surfaces before the ultrasonic actuation was found to be an important prior condition. With improper contact, several bonding defects would occur, such as voids, localized spot melting and edge melting. Under auxiliary ultrasonic vibration, within 10 s, the bond strength developed at the bonding interface could be dramatically improved compared with those achieved without ultrasonic actuation. The enhanced bond strength obtained at a preheating temperature of 20 °C lower than its Tg could be comparable to the strength for pure thermal compression at 5 °C higher than its Tg. It is believed that the ultrasonic energy introduced could elevate the interfacial temperature and facilitate the interdiffusion of molecular chain segments at the interface, consequently resulting in rapidly enhanced bonding. Also, the microchannel distortion after ultrasonic actuation was found to be satisfactory—another important requirement. From dynamic mechanical analysis, the glass transition temperature of COC was found to increase with increasing frequency, and the temperature of the bulk polymer under ultrasonic actuation was still well under Tg; therefore the deformation is minor under ultrasonic actuation.

Shear bond strength of composite bonded with three adhesives to Er,Cr:YSGG laser-prepared enamel.

PubMed

Türkmen, Cafer; Sazak-Oveçoğlu, Hesna; Günday, Mahir; Güngör, Gülşad; Durkan, Meral; Oksüz, Mustafa

2010-06-01

To assess in vitro the shear bond strength of a nanohybrid composite resin bonded with three adhesive systems to enamel surfaces prepared with acid and Er,Cr:YSGG laser etching. Sixty extracted caries- and restoration-free human maxillary central incisors were used. The teeth were sectioned 2 mm below the cementoenamel junction. The crowns were embedded in autopolymerizing acrylic resin with the labial surfaces facing up. The labial surfaces were prepared with 0.5-mm reduction to receive composite veneers. Thirty specimens were etched with Er,Cr:YSGG laser. This group was also divided into three subgroups, and the following three bonding systems were then applied on the laser groups and the other three unlased groups: (1) 37% phosphoric acid etch + Bond 1 primer/adhesive (Pentron); (2) Nano-bond self-etch primer (Pentron) + Nano-bond adhesive (Pentron); and (3) all-in-one adhesive-single dose (Futurabond NR, Voco). All of the groups were restored with a nanohybrid composite resin (Smile, Pentron). Shear bond strength was measured with a Zwick universal test device with a knife-edge loading head. The data were analyzed with two-factor ANOVA. There were no significant differences in shear bond strength between self-etch primer + adhesive and all-in-one adhesive systems for nonetched and laser-etched enamel groups (P > .05). However, bond strength values for the laser-etched + Bond 1 primer/adhesive group (48.00 +/- 13.86 MPa) were significantly higher than the 37% phosphoric acid + Bond 1 primer/adhesive group (38.95 +/- 20.07 MPa) (P < .05). The Er,Cr:YSGG laser-powered hydrokinetic system etched the enamel surface more effectively than 37% phosphoric acid for subsequent attachment of composite material.

Wood structure and adhesive bond strength

Treesearch

Charles R. Frihart

2006-01-01

Much of the literature on the bonding of wood and other lignocellulosic materials has concentrated on traditional adhesion theories. This has led to misconceptions because wood is a porous material on both the macroscopic and microscopic levels. A better understanding of wood bonding can be developed by investigating the theories of adhesion and bond strength, taking...

Effects of ultraviolet irradiation on bonding strength between Co-Cr alloy and citric acid-crosslinked gelatin matrix.

PubMed

Inoue, Motoki; Sasaki, Makoto; Katada, Yasuyuki; Taguchi, Tetsushi

2014-02-01

Novel techniques for creating a strong bond between polymeric matrices and biometals are required. We immobilized polymeric matrices on the surface of biometal for drug-eluting stents through covalent bond. We performed to improve the bonding strength between a cobalt-chromium alloy and a citric acid-crosslinked gelatin matrix by ultraviolet irradiation on the surface of cobalt-chromium alloy. The ultraviolet irradiation effectively generated hydroxyl groups on the surface of the alloy. The bonding strength between the gelatin matrix and the alloy before ultraviolet irradiation was 0.38 ± 0.02 MPa, whereas it increased to 0.48 ± 0.02 MPa after ultraviolet irradiation. Surface analysis showed that the citric acid derivatives occurred on the surface of the cobalt-chromium alloy through ester bond. Therefore, ester bond formation between the citric acid derivatives active esters and the hydroxyl groups on the cobalt-chromium alloy contributed to the enhanced bonding strength. Ultraviolet irradiation and subsequent immobilization of a gelatin matrix using citric acid derivatives is thus an effective way to functionalize biometal surfaces.

Shape Optimization of Bone-Bonding Subperiosteal Devices with Finite Element Analysis.

PubMed

Ogasawara, Takeshi; Uezono, Masayoshi; Takakuda, Kazuo; Kikuchi, Masanori; Suzuki, Shoichi; Moriyama, Keiji

2017-01-01

Subperiosteal bone-bonding devices have been proposed for less invasive treatments in orthodontics. The device is osseointegrated onto a bone surface without fixation screws and is expected to rapidly attain a bone-bonding strength that successfully meets clinical performance. Hence, the device's optimum shape for rapid and strong bone bonding was examined in this study by finite element analyses. First, a stress analysis was performed for a circular rod device with an orthodontic force parallel to the bone surface, and the estimate of the bone-bonding strength based on the bone fracture criterion was verified with the results of an animal experiment. In total, four cross-sectional rod geometries were investigated: circular (Cr), elliptical (El), semicircular (Sc), and rectangular (Rc). By changing the height of the newly formed bone to mimic the progression of new bone formation, the estimation of the bone-bonding strength was repeated for each geometry. The rod with the Rc cross section exhibited the best performance, followed by those with the Sc, El, and Cr cross sections, from the aspects of the rapid acquisition of strength and the strength itself. Thus, the rectangular cross section is the best for rod-like subperiosteal devices for rapid bone bonding.

Magnetic microparticle-polydimethylsiloxane composite for reversible microchannel bonding

PubMed Central

Tsao, Chia-Wen; Lee, Yueh-Pu

2016-01-01

Abstract In this study, an iron oxide magnetic microparticles and poly(dimethylsiloxane) (MMPs-PDMS) composite material was employed to demonstrate a simple high-strength reversible magnetic bonding method. This paper presents the casting of opaque-view (where optical inspection through the microchannels was impossible) and clear-view (where optical inspection through the microchannel was possible) MMPs-PDMS. The influence of the microchannel geometries on the casting of the opaque-view casting was limited, which is similar to standard PDMS casting. Clear-view casting performance was highly associated with the microchannel geometries. The effects of the microchannel layout and the gap between the PDMS cover layer and the micromold substrate were thoroughly investigated. Compared with the native PDMS bonding strength of 31 kPa, the MMPs-PDMS magnetic bonding experiments showed that the thin PDMS film with an MMPs-PDMS layer effectively reduced the surface roughness and enhanced MMPs-PDMS reversible magnetic bonding strength. A thin PDMS film-coated opaque-view MMPs-PDMS device exhibited the greatest bonding strength of 110 kPa, and a clear-view MMPs-PDMS device with a thin PDMS film attained a magnetic bonding strength of 81 kPa. PMID:27877852

Thermal welding of biological tissues derived from porcine aorta for manufacturing bioprosthetic cardiac valves.

PubMed

Figueiredo, Rubem L P; Dantas, Maria Sylvia Silva; Oréfice, Rodrigo L

2011-08-01

Sutures in cardiac valve bioprostheses have several disadvantages as they have to be manually processed and the suturing region is always a mechanically weak spot. Thermal welding of biological tissues has been evaluated as a means of replacing sutures by the direct application of heat to tissues. The mechanical strength of the welds increased up to 50°C and with lower degrees of humidity and longer times of welding. Chemical fixation was essential for the stability of the weld during re-hydration. The average mechanical strength of the welds (0.87 MPa) was lower than the strength of sutures (1.36 MPa) but some results showed strengths that were similar to sutures. Raman and electron micrographs showed that weld formation is primarily associated with chemical bonds between collagen fibers rather than chain flow and interpenetration.

Effect of Mucoprotein on the Bond Strength of Resin Composite to Human Dentin

PubMed Central

Pinzon, Lilliam M; Powers, John M; O'Keefe, Kathy; Dusevish, Vladimir; Spencer, Paulette; Marshall, Grayson W

2010-01-01

The purpose of this study was to test the bond strength and analyze the morphology of the dentin-adhesive interface of two etch and rinse and two self-etch adhesive systems with two kinds of artificial saliva (with and without 450 mg/L mucin) contamination under different conditions of decontaminating the interface. Bonded specimens were sectioned perpendicularly to the bonded surface in 1-mm thick slabs. These 1-mm thick slabs were remounted in acrylic blocks and sectioned in sticks perpendicular to the bonding interfaces with a 1-mm2 area. Nine specimens from each condition were tested after 24 hours on a testing machine (Instron) at a speed of 0.5 mm/min for a total of 360 specimens. Means and standard deviations of bond strength (MPa) were calculated. ANOVA showed significant differences as well as Fisher's PLSD intervals (p<0.05). Different groups results ranges: Control group 34-60 MPa, saliva without mucin 0-52 MPa, and saliva with mucin 0-57 MPa. Failure sites were mixed, adhesive failure was common for the low bond strength results. P&BNT with ideal conditions and following the manufacturer's instructions (control) had the highest bond strengths and the dentin-adhesive interface exhibited an ideal morphology of a etch and rinse system. SEM gave complementary visual evidence of the effect in the dentin/adhesive interface structure with some contaminated conditions compared to their respective control groups. This in-vitro artificial saliva model with and without mucin showed that an organic component of saliva could increase or decrease the bond strength depending on the specific bonding agent and decontamination procedure. PMID:14505182

Effect of Saliva on the Tensile Bond Strength of Different Generation Adhesive Systems: An In-Vitro Study.

PubMed

Gupta, Nimisha; Tripathi, Abhay Mani; Saha, Sonali; Dhinsa, Kavita; Garg, Aarti

2015-07-01

Newer development of bonding agents have gained a better understanding of factors affecting adhesion of interface between composite and dentin surface to improve longevity of restorations. The present study evaluated the influence of salivary contamination on the tensile bond strength of different generation adhesive systems (two-step etch-and-rinse, two-step self-etch and one-step self-etch) during different bonding stages to dentin where isolation is not maintained. Superficial dentin surfaces of 90 extracted human molars were randomly divided into three study Groups (Group A: Two-step etch-and-rinse adhesive system; Group B: Two-step self-etch adhesive system and Group C: One-step self-etch adhesive system) according to the different generation of adhesives used. According to treatment conditions in different bonding steps, each Group was further divided into three Subgroups containing ten teeth in each. After adhesive application, resin composite blocks were built on dentin and light cured subsequently. The teeth were then stored in water for 24 hours before sending for testing of tensile bond strength by Universal Testing Machine. The collected data were then statistically analysed using one-way ANOVA and Tukey HSD test. One-step self-etch adhesive system revealed maximum mean tensile bond strength followed in descending order by Two-step self-etch adhesive system and Two-step etch-and-rinse adhesive system both in uncontaminated and saliva contaminated conditions respectively. Unlike One-step self-etch adhesive system, saliva contamination could reduce tensile bond strength of the two-step self-etch and two-step etch-and-rinse adhesive system. Furthermore, the step of bonding procedures and the type of adhesive seems to be effective on the bond strength of adhesives contaminated with saliva.

Repair Strength in Simulated Restorations of Methacrylate- or Silorane-Based Composite Resins.

PubMed

Consani, Rafael Leonardo Xediek; Marinho, Tatiane; Bacchi, Atais; Caldas, Ricardo Armini; Feitosa, Victor Pinheiro; Pfeifer, Carmem Silvia

2016-01-01

The study verified the bond strength in simulated dental restorations of silorane- or methacrylate-based composites repaired with methacrylate-based composite. Methacrylate- (P60) or silorane-based (P90) composites were used associated with adhesive (Adper Single Bond 2). Twenty-four hemi-hourglass-shaped samples were repaired with each composite (n=12). Samples were divided according to groups: G1= P60 + Adper Single Bond 2+ P60; G2= P60 + Adper Single Bond 2 + P60 + thermocycling; G3= P90 + Adper Single Bond 2 + P60; and G4= P90 + Adper Single Bond 2 + P60 + thermocycling. G1 and G3 were submitted to tensile test 24 h after repair procedure, and G2 and G4 after submitted to 5,000 thermocycles at 5 and 55 ?#61616;C for 30 s in each bath. Tensile bond strength test was accomplished in an universal testing machine at crosshead speed of 0.5 mm/min. Data (MPa) were analyzed by two-way ANOVA and Tukey's test (5%). Sample failure pattern (adhesive, cohesive in resin or mixed) was evaluated by stereomicroscope at 30?#61655; and images were obtained in SEM. Bond strength values of methacrylate-based composite samples repaired with methacrylate-based composite (G1 and G2) were greater than for silorane-based samples (G3 and G4). Thermocycling decreased the bond strength values for both composites. All groups showed predominance of adhesive failures and no cohesive failure in composite resin was observed. In conclusion, higher bond strength values were observed in methacrylate-based resin samples and greater percentage of adhesive failures in silorane-based resin samples, both composites repaired with methacrylate-based resin.

Effect of 2% chlorhexidine digluconate on bond strength of a glass-fibre post to root dentine.

PubMed

Wang, L; Pinto, T A; Silva, L M; Araújo, D F G; Martins, L M; Hannas, A R; Pedreira, A P R V; Francisconi, P A S; Honório, H M

2013-09-01

To assess the immediate influence of dentine bonding systems (DBS) associated with 2% chlorhexidine digluconate (CHX) on glass-fibre post-bond strength to root dentine, in terms of coronal, middle and apical thirds. Sixty bovine roots were root filled and randomly assigned to 1 of 6 groups (n = 10): SBMP (3-step etch-and-rinse system, Scotchbond Multi-Purpose), SB (2-step etch-and-rinse system, Single Bond 2), SE (2-step self-etching system, Clearfil SE Bond) and SBMP-CHX, SB-CHX and SE-CHX, respectively, associated with CHX. For all groups, a glass-fibre post was luted with a dual-cure resin cement, RelyX ARC. After 7-day storage, specimens were subjected to the push-out test. Failure modes were analysed under optical microscopy (40x). Bond strength values were statistically analysed by two-way anova and Bonferroni tests (P < 0.05). The effect of DBS was significant (P < 0.05), and SE reached higher bond strength in comparison with the other DBS tested. CHX association did not show improvement with any DBS (P > 0.05); rather, it negatively affected SE, which was detected for all thirds. There was no difference between thirds (P > 0.05), except for the SE-CHX, which presented lower values for the apical third (P < 0.05). Adhesive cement/dentine adhesive failure was predominant for all groups. CHX did not influence the failure mode for any DBS (P > 0.05). The performance of the dentine bonding systems was material dependent. CHX did not improve immediate bond strength; however, CHX negatively affected the bond strength of the self-etching system, especially in the third apical. © 2013 International Endodontic Journal. Published by John Wiley & Sons Ltd.

Influence of warm air-drying on enamel bond strength and surface free-energy of self-etch adhesives.

PubMed

Shiratsuchi, Koji; Tsujimoto, Akimasa; Takamizawa, Toshiki; Furuichi, Tetsuya; Tsubota, Keishi; Kurokawa, Hiroyasu; Miyazaki, Masashi

2013-08-01

We examined the effect of warm air-drying on the enamel bond strengths and the surface free-energy of three single-step self-etch adhesives. Bovine mandibular incisors were mounted in self-curing resin and then wet ground with #600 silicon carbide (SiC) paper. The adhesives were applied according to the instructions of the respective manufacturers and then dried in a stream of normal (23°C) or warm (37°C) air for 5, 10, and 20 s. After visible-light irradiation of the adhesives, resin composites were condensed into a mold and polymerized. Ten samples per test group were stored in distilled water at 37°C for 24 h and then the bond strengths were measured. The surface free-energies were determined by measuring the contact angles of three test liquids placed on the cured adhesives. The enamel bond strengths varied according to the air-drying time and ranged from 15.8 to 19.1 MPa. The trends for the bond strengths were different among the materials. The value of the γS⁺ component increased slightly when drying was performed with a stream of warm air, whereas that of the γS⁻ component decreased significantly. These data suggest that warm air-drying is essential to obtain adequate enamel bond strengths, although increasing the drying time did not significantly influence the bond strength. © 2013 Eur J Oral Sci.

Bond Capability of Universal Adhesive Systems to Dentin in Self-etch Mode after Short-term Storage and Cyclic Loading

PubMed Central

Costa, Daniele Morosini; Somacal, Deise Caren; Borges, Gilberto Antonio; Spohr, Ana Maria

2017-01-01

Objective: The aim was to evaluate, in vitro, the tensile bond strength to dentin of Scotchbond Universal (SU), All-Bond Universal (AU) and One Coat 7 Universal (OC7) adhesives applied in self-etch mode, after 24 h of storage and after 500,000 loading cycles, using Clearfil SE Bond (SE) as a control. Materials and Methods: The adhesives were applied on the dentin of bovine teeth, followed by the application of a composite resin. Thirty specimens were obtained for each adhesive. Half of the specimens were submitted to cyclic loading for 500,000 cycles. All specimens were submitted to a tensile bond strength test in a universal testing machine at a crosshead speed of 0.5 mm/minute. Results: According to two-way ANOVA and Tukey’s test (α=5%), the interaction between the adhesive and cyclic loading factors was significant (p=0.001). The means followed by the same letter represent no significant difference in the bond strength (MPa) after 24 h: OC7=7.86A (±2.90), SU=6.78AB (±2.03), AU=5.61BC (±2.32), and SE=3.53C (±1.89). After cyclic loading, SE, SU and AU maintained bond strength comparable to 24 h period. There was a significant decrease only for OC7. Conclusion: SU, AU and OC7 had bond strength to dentin comparable to that of SE. Only OC7 had decreased bond strength to dentin after cyclic loading. PMID:28839476

Effect of sandblasting, silica coating, and laser treatment on the microtensile bond strength of a dental zirconia ceramic to resin cements.

PubMed

Mahmoodi, Nasrin; Hooshmand, Tabassom; Heidari, Solmaz; Khoshro, Kimia

2016-02-01

The purpose of this in vitro study was to evaluate the effect of laser irradiation as well as other surface treatment methods on the microtensile bond strength of a dental zirconia ceramic to the two types of resin cements. Zirconia ceramic blocks (ICE Zirkon) were sintered according to the manufacturer's instructions and duplicated in resin composites. The ceramic specimens were divided into four groups according to the following surface treatments: no surface treatment (control), sandblasting with alumina, silica coating plus silanization, and Nd:YAG laser irradiation. The specimens were divided equally and then bonded with Panavia F2.0 (self-etching resin cement) and Clearfil SA Luting (self-adhesive resin cement) to the composite blocks. The bonded ceramic-composite blocks were stored in distilled water at 37 °C for 72 h, cut to prepare bar-shaped specimens with a bonding area of approximately 1 mm(2), and thermocycled for 3000 cycles between 5 and 55 °C, and the microtensile bond strengths were measured using a universal testing machine. The data were analyzed by ANOVA and Tukey post hoc test. The results showed that the self-adhesive resin cement used in this study did not improve the microtensile bond strength when the zirconia surface was sandblasted by alumina. The use of the Nd:YAG laser did not enhance the bond strength between the zirconia and both types of resin cements. In addition, silica coating of the zirconia surfaces plus silane application significantly improved the bond strength regardless of the type of resin cement utilized.

Tensile Bond Strength of So-called Universal Primers and Universal Multimode Adhesives to Zirconia and Lithium Disilicate Ceramics.

PubMed

Elsayed, Adham; Younes, Feras; Lehmann, Frank; Kern, Matthias

2017-01-01

To test the bond strength and durability after artificial aging of so-called universal primers and universal multimode adhesives to lithium disilicate or zirconia ceramics. A total of 240 ceramic plates, divided into two groups, were produced and conditioned: 120 acid-etched lithium disilicate plates (IPS e.max CAD) and 120 air-abraded zirconia plates (Zenostar T). Each group was divided into five subgroups (n = 24), and a universal restorative primer or multimode universal adhesive was used for each subgroup to bond plexiglas tubes filled with a composite resin to the ceramic plate. The specimens were stored in water at 37°C for 3 days without thermal cycling, or for 30 or 150 days with 7500 or 37,500 thermal cycles between 5°C and 55°C, respectively. All specimens then underwent tensile bond strength testing. Initially, all bonding systems exhibited high TBS, but some showed a significant reduction after 30 and 150 days of storage. After 3, 30, and 150 days, Monobond Plus, which contains silane and phosphate monomer, showed significantly higher bond strengths than the other universal primer and adhesive systems. The bond strength to lithium disilicate and zirconia ceramic is significantly affected by the bonding system used. Using a separate primer containg silane and phosphate monomer provides more durable bonding than do silanes incorporated in universal multimode adhesives. Only one of five so-called universal primers and adhesives provided durable bonding to lithium disilicate and zirconia ceramic.

Self-etching adhesive on intact enamel, with and without pre-etching.

PubMed

Devarasa, G M; Subba Reddy, V V; Chaitra, N L; Swarna, Y M

2012-05-01

Bond strengths of composite resin to enamel using self-etch adhesive (SEA) Clearfil SE bond system on intact enamel and enamel pre-etched with phosphoric acid were compared. The objective was to determine if the pre-etching would increase the bond strengths of the SEA systems to intact enamel and to evaluate the effect of pre-etching on bond formation of self-etch adhesives on intact enamel. Labial surfaces of 40 caries free permanent upper central and lateral incisors were cleaned, sectioned of their roots. All specimens were mounted on acrylic block and divided randomly into four groups. In two groups the application of self-etch adhesive, Clearfil SE bond was carried as per manufacturer's instructions, composite cylinders were built, whereas in the other two groups, 37% phosphoric acid etching was done before the application of self-etching adhesives. Then the resin tags were analyzed using scanning electron microscope and shear bond strength was measured using Instron universal testing machine. When phosphoric acid was used, there was significant increase in the depth of penetration of resin tags and in the Shear Bond Strength of composite to enamel. The results indicate that out of both treatment groups, pre-etching the intact enamel with 37% phosphoric acid resulted in formation of longer resin tags and higher depth of penetration of resin tags of the Clearfil SE bond, and attaining higher bond strength of the Clearfil SE bond to intact enamel. Copyright © 2011 Wiley Periodicals, Inc.

Effects of Different Radiation Doses on the Bond Strengths of Two Different Adhesive Systems to Enamel and Dentin.

PubMed

da Cunha, Sandra Ribeiro de Barros; Ramos, Pedro Augusto Minorin Mendes; Haddad, Cecília Maria Kalil; da Silva, João Luis Fernandes; Fregnani, Eduardo Rodrigues; Aranha, Ana Cecília Corrêa

2016-01-01

To evaluate the effects of three different radiation doses on the bond strengths of two different adhesive systems to enamel and dentin. Eighty human third molars were randomly divided into four groups (n = 20) according to the radiation dose (control/no radiation, 20 Gy, 40 Gy, and 70 Gy). The teeth were sagittally sectioned into three slices: one mesial and one distal section containing enamel and one middle section containing dentin. The sections were then placed in the enamel and dentin groups, which were further divided into two subgroups (n = 10) according to the adhesive used. Three restorations were performed in each tooth (one per section) using Adper Single Bond 2 (3M ESPE) or Universal Single Bond (3M ESPE) adhesive system and Filtek Z350 XT (3M ESPE) resin composite and subjected to the microshear bond test. Data were analyzed using a two-way ANOVA followed by Tukey's test. Failure modes were examined under a stereoscopic loupe. Radiotherapy did not affect the bond strengths of the adhesives to either enamel or dentin. In dentin, the Universal Single Bond adhesive system showed higher bond strength values when compared with the Adper Single Bond adhesive system. More adhesive failures were observed in the enamel for all radiation doses and adhesives. Radiotherapy did not influence the bond strength to enamel or dentin, irrespective of the adhesive or radiation dose used.

[The influence of surface conditioning on the shear bond strength of La-Porcelain and titanium].

PubMed

Mo, Anchun; Cen, Yuankun; Liao, Yunmao

2003-04-20

To determine the influence of different surface conditioning methods on bonding strength of low fusing porcelain (La-Porcelain) and titanium. The surface of the samples were sandblasted for 2 min with 80-250 microns Al2O3 or coated for two times with Si-couple agent or conditioned by pre-oxidation. The shear bond strength was examined by push-type shear test with a speed of 0.5 mm/min in a universal testing machine. Scanning electron microscopy (SEM) and electron probe micro-analyzer (EPMA) were employed to explore the relationship between bonding strength and microstructures, as well as the element diffusion at the interface between porcelain coating and titanium when heated at 800 degrees C. Bonding strength was not statistically different (P > 0.05) after sandblasting with Al2O3 in particle size ranged from 80 microns to 250 microns. When a Si-couple agent was used, bond of porcelain to titanium was significantly lower (P < 0.05). The shear bond strength of the porcelain to the pre-oxidized titanium surface remained unchanged after heating (P > 0.05). The SEM results revealed integrity of porcelain and titanium. La-Porcelain showed a small effect of surface coarseness. Sandblasting the titanium surface with 150-180 microns Al2O3 can be recommended as a method for better bonding between La-Porcelain and titanium. The Si-couple agent coating and pre-oxidation of titanium surface is unnecessary.

The effect of antimicrobial agents on bond strength of orthodontic adhesives: a meta-analysis of in vitro studies.

PubMed

Altmann, A S P; Collares, F M; Leitune, V C B; Samuel, S M W

2016-02-01

Antimicrobial orthodontic adhesives aim to reduce white spot lesions' incidence in orthodontic patients, but they should not jeopardizing its properties. Systematic review and meta-analysis were performed to answer the question whether the association of antimicrobial agents with orthodontic adhesives compromises its mechanical properties and whether there is a superior antimicrobial agent. PubMed and Scopus databases. In vitro studies comparing shear bond strength of conventional photo-activated orthodontic adhesives to antimicrobial photo-activated orthodontic adhesives were considered eligible. Search terms included the following: orthodontics, orthodontic, antimicrobial, antibacterial, bactericidal, adhesive, resin, resin composite, bonding agent, bonding system, and bond strength. The searches yielded 494 citations, which turned into 467 after duplicates were discarded. Titles and abstracts were read and 13 publications were selected for full-text reading. Twelve studies were included in the meta-analysis. The global analysis showed no statistically significant difference between control and experimental groups. In the subgroup analysis, only the chlorhexidine subgroup showed a statistically significant difference, where the control groups had higher bond strength than the experimental groups. Many studies on in vitro orthodontic bond strength fail to report test conditions that could affect their outcomes. The pooled in vitro data suggest that adding an antimicrobial agent to an orthodontic adhesive system does not influence bond strength to enamel. It is not possible to state which antimicrobial agent is better to be associated. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Effects of silicon coating on bond strength of two different titanium ceramic to titanium.

PubMed

Ozcan, Isil; Uysal, Hakan

2005-08-01

This study investigated the effect of silicon coating (SiO2) by magnetron sputtering on bond strength of two different titanium ceramics to titanium. Sixty cast titanium specimens were prepared following the protocol ISO 9693. Titanium specimens were divided into two test and control groups with 15 specimens in each. Test groups were silicon coated by the magnetron sputtering technique. Two titanium ceramics (Triceram and Duceratin) were applied on both test (coated) and control (uncoated) metal specimens. The titanium-ceramic specimens were subjected to a three point flexural test. The groups were compared for their bond strength. SEM and SEM/EDS analyses were performed on the delaminated titanium surfaces to ascertain bond failure. The mean bond strength of Ti-Duceratin, Ti-Triceram, Si-coated Ti-Duceratin and Si-coated Ti-Triceram were 17.22+/-2.43, 23.31+/-3.18, 23.21+/-3.81 and 24.91+/-3.70 MPa, respectively. While the improvement in bond strength was 30% for Duceratin, it was statistically insignificant for Triceram. An adhesive mode of failure was observed in the Duceratin control group. In the silicoated Duceratin specimen, the bonded ceramic boundaries were wider but less than in the silicoated Triceram specimen. In the coated Triceram specimen, the ceramic retained areas were frequent and the failure mode was generally cohesive. Silicon coating was significantly effective in both preventing titanium oxide layer formation and in improving bond strength for Duceratin. However, it was of less value for Triceram.

Verification of surface preparation for adhesive bonding

NASA Technical Reports Server (NTRS)

Myers, Rodney S.

1995-01-01

A survey of solid rocket booster (SRB) production operations identified potential contaminants which might adversely affect bonding operations. Lap shear tests quantified these contaminants' effects on adhesive strength. The most potent contaminants were selected for additional studies on SRB thermal protection system (TPS) bonding processes. Test panels were prepared with predetermined levels of contamination, visually inspected using white and black light, then bonded with three different TPS materials over the unremoved contamination. Bond test data showed that white and black light inspections are adequate inspection methods for TPS bonding operations. Extreme levels of contamination (higher than expected on flight hardware) had an insignificant effect on TPS bond strengths because of the apparent insensitivity of the adhesive system to contamination effects, and the comparatively weak cohesive strength of the TPS materials.

Influence of Different Etching Modes on Bond Strength to Enamel using Universal Adhesive Systems.

PubMed

Diniz, Ana Cs; Bandeca, Matheus C; Pinheiro, Larissa M; Dos Santosh Almeida, Lauber J; Torres, Carlos Rg; Borges, Alvaro H; Pinto, Shelon Cs; Tonetto, Mateus R; De Jesus Tavarez, Rudys R; Firoozmand, Leily M

2016-10-01

The adhesive systems and the techniques currently used are designed to provide a more effective adhesion with reduction of the protocol application. The objective of this study was to evaluate the bond strength of universal adhesive systems on enamel in different etching modes (self-etch and total etch). The mesial and distal halves of 52 bovine incisors, healthy, freshly extracted, were used and divided into seven experimental groups (n = 13). The enamel was treated in accordance with the following experimental conditions: FUE-Universal System - Futurabond U (VOCO) with etching; FUWE - Futurabond U (VOCO) without etching; SB-Total Etch System - Single Bond 2 (3M); SBUE-Universal System - Single Bond Universal (3M ESPE) with etching; SBUWE - Single Bond Universal (3M ESPE) without etching; CLE-Self-etch System - Clearfil SE Bond (Kuraray) was applied with etching; CLWE - Clearfil SE Bond (Kuraray) without etching. The specimens were made using the composite spectrum TPH (Dentsply) and stored in distilled water (37 ± 1°C) for 1 month. The microshear test was performed using the universal testing machine EMIC DL 2000 with the crosshead speed of 0.5 mm/minute. The bond strength values were analyzed using statistical tests (Kruskal-Wallis test and Mann-Whitney test) with Bonferroni correction. There was no statistically significant difference between groups (p < 0.05), where FUE (36.83 ± 4.9 MPa) showed the highest bond strength values and SBUWE (18.40 ± 2.2 MPa) showed the lowest bond strength values. The analysis of adhesive interface revealed that most failures occurred between the interface composite resin and adhesive. The universal adhesive system used in dental enamel varies according to the trademark, and the previous enamel etching for universal systems and the self-etch both induced greater bond strength values. Selective enamel etching prior to the application of a universal adhesive system is a relevant strategy for better performance bonding.

GROUT-CONCRETE INTERFACE BOND PERFORMANCE: EFFECT OF INTERFACE MOISTURE ON THE TENSILE BOND STRENGTH AND GROUT MICROSTRUCTURE.

PubMed

De la Varga, I; Muñoz, J F; Bentz, D P; Spragg, R P; Stutzman, P E; Graybeal, B A

2018-05-01

Bond between two cementitious materials is crucial in applications such as repairs, overlays, and connections of prefabricated bridge elements (PBEs), to name just a few. It is the latter that has special interest to the authors of this paper. After performing a dimensional stability study on grout-like materials commonly used as connections between PBEs, it was observed that the so-called 'non-shrink' cementitious grouts showed a considerable amount of early-age shrinkage. This might have negative effects on the integrity of the structure, due not only to the grout material's early degradation, but also to a possible loss of bond between the grout and the prefabricated concrete element. Many factors affect the bond strength between two cementitious materials (e.g., grout-concrete), the presence of moisture at the existing concrete substrate surface being one of them. In this regard, pre-moistening the concrete substrate surface prior to the application of the grout material is sometimes recommended for bond enhancement. This topic has been the focus of numerous research studies in the past; however, there is still controversy among practitioners on the real benefits that this practice might provide. This paper evaluates the tensile bond performance of two non-shrink cementitious grouts applied to the exposed aggregate surface of a concrete substrate, and how the supply of moisture at the grout-concrete interface affects the bond strength. "Pull-off" bond results show increased tensile bond strength when the concrete surface is pre-moistened. Reasons to explain the observed increased bond strength are given after a careful microstructural analysis of the grout-concrete interface. Interfaces where sufficient moisture is provided to the concrete substrate such that moisture movement from the grout is prevented show reduced porosity and increased hydration on the grout side of the interface, which is thought to directly contribute to the increased tensile bond strength.

Microshear Bond Strength of OptiBond All-in-One Self-adhesive Agent to Er:YAG Laser Treated Enamel After Thermocycling and Water Storage.

PubMed

Kasraei, Shahin; Yarmohammadi, Ebrahim; Ghazizadeh, Mohammad Vahid

2016-01-01

Introduction: This study aimed to compare the microshear bond strength of composite to enamel treated with Erbium-Doped Yttrium Aluminum Garnet (Er:YAG) laser using a self-etch one step bonding agent. Methods: Seventy-six enamel surfaces were prepared from 38 sound human third molar teeth. Specimens were randomly divided into four groups of 18. The enamel surface in half the specimens was irradiated with Er:YAG laser. One extra specimen from each group was evaluated under a scanning electron microscope (SEM). Composite micro-cylinders were bonded to the specimen surfaces using OptiBond All-In-One (OB) adhesive agent and stored in distilled water for 24 hours. Half the specimens were thermocycled (2000 cycles) and stored in distilled water at 37°C for three months (TW). The microshear bond strength of composite to enamel was measured using a universal testing machine at a crosshead speed of 1 mm/min. The fractured surfaces were evaluated under a stereomicroscope at ×40 magnification to determine the mode of failure. Data were analyzed using repeated measures analysis of variance (ANOVA) and t test. Results: The mean values (±standard deviation) were 17.96 ± 2.92 MPa in OB group, 22.29 ± 4.25 MPa in laser + OB group, 18.11 ± 3.52 MPa in laser + OB + TW group and 9.42 ± 2.47 MPa in OB + TW group. Repeated measures ANOVA showed that laser irradiation increased the microshear bond strength ( P < 0.001). Bond strength decreased when the samples were thermocycled and stored for three months ( P < 0.001). The interaction effect of water storage and laser treatment on bond strength was significant ( P < 0.05). Conclusion: Enamel surface preparation with Er:YAG laser is recommended to enhance the durability of the bond of self-etch bonding systems to enamel.

Microshear Bond Strength of OptiBond All-in-One Self-adhesive Agent to Er:YAG Laser Treated Enamel After Thermocycling and Water Storage

PubMed Central

Kasraei, Shahin; Yarmohammadi, Ebrahim; Ghazizadeh, Mohammad Vahid

2016-01-01

Introduction: This study aimed to compare the microshear bond strength of composite to enamel treated with Erbium-Doped Yttrium Aluminum Garnet (Er:YAG) laser using a self-etch one step bonding agent. Methods: Seventy-six enamel surfaces were prepared from 38 sound human third molar teeth. Specimens were randomly divided into four groups of 18. The enamel surface in half the specimens was irradiated with Er:YAG laser. One extra specimen from each group was evaluated under a scanning electron microscope (SEM). Composite micro-cylinders were bonded to the specimen surfaces using OptiBond All-In-One (OB) adhesive agent and stored in distilled water for 24 hours. Half the specimens were thermocycled (2000 cycles) and stored in distilled water at 37°C for three months (TW). The microshear bond strength of composite to enamel was measured using a universal testing machine at a crosshead speed of 1 mm/min. The fractured surfaces were evaluated under a stereomicroscope at ×40 magnification to determine the mode of failure. Data were analyzed using repeated measures analysis of variance (ANOVA) and t test. Results: The mean values (±standard deviation) were 17.96 ± 2.92 MPa in OB group, 22.29 ± 4.25 MPa in laser + OB group, 18.11 ± 3.52 MPa in laser + OB + TW group and 9.42 ± 2.47 MPa in OB + TW group. Repeated measures ANOVA showed that laser irradiation increased the microshear bond strength (P < 0.001). Bond strength decreased when the samples were thermocycled and stored for three months (P < 0.001). The interaction effect of water storage and laser treatment on bond strength was significant (P < 0.05). Conclusion: Enamel surface preparation with Er:YAG laser is recommended to enhance the durability of the bond of self-etch bonding systems to enamel. PMID:28144434

Incorporation of TiO2 nanotubes in a polycrystalline zirconia: Synthesis of nanotubes, surface characterization, and bond strength.

PubMed

Dos Santos, Angélica Feltrin; Sandes de Lucena, Fernanda; Sanches Borges, Ana Flávia; Lisboa-Filho, Paulo Noronha; Furuse, Adilson Yoshio

2018-04-05

Despite numerous advantages such as high strength, the bond of yttria-stabilized zirconia polycrystal (Y-TZP) to tooth structure requires improvement. The purpose of this in vitro study was to evaluate the incorporation of TiO 2 nanotubes into zirconia surfaces and the bond strength of resin cement to the modified ceramic. TiO 2 nanotubes were produced by alkaline synthesis, mixed with isopropyl alcohol (50 wt%) and applied on presintered zirconia disks. The ceramics were sintered, and the surfaces were characterized by confocal laser microscopy, scanning electron microscopy (SEM), and energy-dispersive x-ray spectroscopy (EDS) analysis. For bond strength, the following 6 groups (n=16) were evaluated: without TiO 2 and Single Bond Universal; with TiO 2 nanotubes and Single Bond Universal; without TiO 2 nanotubes and Z-prime; with TiO 2 nanotubes and Z-prime; without TiO 2 and Signum Zirconia Bond; with TiO 2 and Signum Zirconia Bond. After sintering, resin cement cylinders, diameter of 1.40 mm and 1 mm in height, were prepared and polymerized for 20 seconds. Specimens were stored in water at 37°C for 30 days and submitted to a shear test. Data were analyzed by 2-way ANOVA and Tukey honest significant difference (α=.05) tests. EDS analysis confirmed that nanoagglomerates were composed of TiO 2 . The shear bond strength showed statistically significant differences among bonding agents (P<.001). No significant differences were found with the application of nanotubes, regardless of the group analyzed (P=.682). The interaction among the bonding agent factors and addition of nanotubes was significant (P=.025). Nanotubes can be incorporated into zirconia surfaces. However, this incorporation did not improve bond strength. Copyright © 2017 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Microtensile bond strength of contemporary adhesives to primary enamel and dentin.

PubMed

Marquezan, Marcela; da Silveira, Bruno Lopes; Burnett, Luiz Henrique; Rodrigues, Célia Regina Martins Delgado; Kramer, Paulo Floriani

2008-01-01

The purpose of this study was to assess bond strength of three self-etching and two total-etch adhesive systems bonded to primary tooth enamel and dentin. Forty extracted primary human molars were selected and abraded in order to create flat buccal enamel and occlusal dentin surfaces. Teeth were assigned to one of the adhesive systems: Adper Scotch Bond Multi Purpose, Adper Single Bond 2, Adper Prompt L-Pop, Clearfil SE Bond and AdheSE. Immediately to adhesive application, a composite resin (Filtek Z250) block was built up. After 3 months of water storage, each sample was sequentially sectioned in order to obtain sticks with a square cross-sectional area of about 0.72 mm2. The specimens were fixed lengthways to a microtensile device and tested using a universal testing machine with a 50-N load cell at a crosshead speed of 0.5 mm/min. Microtensile bond strength values were recorded in MPa and compared by Analysis of Variance and the post hoc Tukey test (a = 0.05). In enamel, Clearfil SE Bond presented the highest values, followed by Adper Single Bond 2, AdheSE and Adper Scotch Bond Multi Purpose, without significant difference. The highest values in dentin were obtained with Adper Scotch Bond Multi Purpose and all other adhesives did not present significant different values from that, except Adper Prompt L-Pop that achieved the lowest bond strength in both substrates. Adper Scotch Bond Multi Purpose and Adper Single Bond 2 presented significantly lower values in enamel than in dentin although all other adhesives presented similar results in both substrates. contemporary adhesive systems present similar behaviors when bonded to primary teeth, with the exception of the one-step self-etching system; and self-etching systems can achieve bond strength values as good in enamel as in dentin of primary teeth.

Factors Affecting the Shear Bond Strength of Orthodontic Brackets - a Review of In Vitro Studies.

PubMed

Bakhadher, Waleed; Halawany, Hassan; Talic, Nabeel; Abraham, Nimmi; Jacob, Vimal

2015-01-01

The adhesive material used to bond orthodontic brackets to teeth should neither fail during the treatment period, resulting in treatment delays, untoward expenses or patient inconvenience nor should it damage the enamel on debonding at the end of the treatment. Although the effectiveness of a bonding system and any unfavorable effects on the enamel may be studied by conducting in-vivo studies, it is nearly impossible to independently analyze different variables that influence a specific bonding system in the oral environment. In-vitro studies, on the other hand, may utilize more standardized protocols for testing different bonding systems and materials available. Thus, the present review focused attention on in-vitro studies and made an attempt to discuss material-related, teeth-related (fluorotic vs non-fluorotic teeth) and other miscellaneous factors that influences the shear bond strength of orthodontic brackets. Within the limitations of this review, using conventional acid-etch technique, ceramic brackets and bonding to non-fluorotic teeth was reported to have a positive influence on the shear bond strength of orthodontic brackets, but higher shear bond strength found on using ceramic brackets can be dangerous for the enamel.

[Effect of nano-silica coating on bonding strength of zirconia ceramics to dentin].

PubMed

Zhang, Xian-Fang; Zheng, Hu; Han, Dong-Wei

2009-04-01

To investigate the effect of silica coating by sol-gel process on bonding strength of zirconia ceramics to dentin. Blocks of sintered zirconia ceramics were cut and randomly divided into 4 groups,16 slices in each group. Each group was subject to one of the 4 kinds of surface treatment (control group, sandblasting, sandblasting +silicone, sandblasting + silica coating + silicone) and then bonded to dentin with resin cement. After preservation in 37 degrees centigrade distilled water for 24 hours, the shear bonding strength of these specimens was tested and the data was analyzed with SAS6.12 software package for analysis of variance. The surface modality of the ceramics was observed under scanning electron microscopy (SEM). The group of sandblasting+ silica coating + silicone attained the highest shear bonding strength, which was significantly different from the other groups(P=0.000);There was no significant difference between the sandblasting and sandblasting + silicone group (P=0.827), which was significantly different from the control group(P=0.001). Silica coating by sol-gel process, coupled with silicone, can significantly increase the bonding strength of zirconia ceramics to dentin.

The influence of salivary contamination on shear bond strength of dentin adhesive systems.

PubMed

Park, Jeong-won; Lee, Kyung Chae

2004-01-01

This study evaluated the influence of salivary contamination during dentin bonding procedures on shear bond strength and investigated the effect of contaminant-removing treatments on the recovery of bond strength for two dentin bonding agents. One hundred and ten human molars were embedded in cylindrical molds with self-curing acrylic resin. The occlusal dentin surface was exposed by wet grinding with #800 silicon carbide abrasive paper. The teeth were divided into five groups for One-step (OS) (BISCO, Inc) and six groups for Clearfil SE Bond (SE) (Kuraray Co, Ltd, Osaka, Japan). For One-step, the grinding surface was treated with 32% phosphoric acid; BAC (BISCO Inc) and divided into five groups: OS control group (uncontaminated), OS I (salivary contamination, blot dried), OS II (salivary contamination, completely dried), OS III (salivary contamination, wash and blot dried) and OS IV (salivary contamination, re-etching for 10 seconds, wash and blot dried). For SE bond, the following surface treatments were done: SE control group (primer applied to the fresh dentin surface), SE I (after salivary contamination, primer applied), SE II (primer, salivary contamination, dried), SE III (primer, salivary contamination, wash and dried), SE IV (after procedure of SE II, re-application of primer) and SE V (after procedure of SE III, re-application of primer). Each bonding agent was applied and light cured for 10 seconds. Clearfil AP-X (Kuraray Co, Ltd) composite was packed into the Ultradent mount jig mold and light cured for 40 seconds. The bonded specimens were stored for 24 hours in a 37 degrees C waterbath. The shear bond strengths were measured using an Instron testing machine (Model 4202, Instron Corp). The data for each group were subjected to one-way ANOVA followed by the Newman-Keuls test to make comparisons among the groups. The results were as follows: In the One-step groups, the OS II group showed statistically significant lower shear bond strength than the OS control, I, III and IV (p<0.05). In the Clearfil SE Bond groups, the SE II and SE III groups had decreased shear bond strength compared with the control and SE I, SE IV and SE V groups (p<0.05). In conclusion, when using One-step total etch adhesive and when the etched surface is contaminated by saliva, blotting the surface and applying the primer can recover the bond strength. Complete drying of the salivary contaminated surface should be avoided. In the Clearfil SE Bond groups, the re-priming treatment (SE IV and SE V) resulted in the recovery of shear bond strength in the specimens contaminated after priming.

[Influence of different porcelain surface treatment method on the bonding of metal brackets to porcelain].

PubMed

Fan, Cun-Hui; Chen, Jie; Liu, Xin-Qiang; Ma, Xin

2005-08-01

To investigate the influence of different porcelain surface treatment methods on the shear bond strength of metal brackets bonded to porcelain. 80 porcelain facets were divided randomly into two groups according to different adhesive material that was used to bond metal brackets. Adhesive material were Jing-Jin enamel adhesive and light-cured composite resin. Each group was further divided into 4 subgroups according to different surface treatment methods, which were acid etching with 37% phosphoric acid (H3PO4), acid etching with 9.6% hydrofluoric acid (HF), deglazing by grinding and silanating the porcelain surface. All specimens were stored in 37 degrees C water for 24 hours and then the shear bond strength and the porcelain fracture after debonding was determined. The porcelain surfaces after HF etching, H3PO4 etching and deglazing by grinding were examined by scanning electron microscopy respectively. The shear bond strengths in the HF etching groups, the deglazing groups and the silanating groups were much greater than that in the phosphoric etching groups (P < 0.01). Adequate orthodontic bonding strength was achieved both when bonded with light-cured composite resin after deglazing by grinding and when bonded with either of these adhesives after HF etching or surface silanating. There were no differences in the rates of porcelain fractures among groups (P > 0.05). HF etching, deglazing by grinding and silanating can all increase the shear bond strength between metal bracket and porcelain. Surface silanating of porcelain is a better surface treatment when metal brackets bonded to porcelain.

Effect of 2% Chlorhexidine Digluconate on the Bond Strength to Normal versus Caries-Affected Dentin

PubMed Central

Komori, Paula C. P.; Pashley, David H.; Tjäderhane, Leo; Breschi, Lorenzo; Mazzoni, Annalisa; de Goes, Mario Fernando; Wang, Linda; Carrilho, Marcela R.

2013-01-01

SUMMARY This study evaluated the effect of 2% chlorhexidine digluconate (CHX) used as a therapeutic primer on the long-term bond strengths of two etch-and-rinse adhesives to normal (ND) and caries-affected (CAD) dentin. Forty extracted human molars with coronal carious lesions, surrounded by normal dentin, were selected for this study. Flat surfaces of two types of dentin (i.e. ND and CAD) were prepared with a water-cooled high speed diamond disc, and then acid-etched, rinsed and air-dried. In control groups, dentin was re-hydrated with distilled water, blot-dried and bonded with a three-step (Scotchbond Multi-Purpose-MP) or a two-step (Single Bond 2-SB) etch-and-rinse adhesive. In experimental groups, dentin was re-hydrated with 2% CHX (60 s), blot-dried and bonded with the same adhesives. Resin composite build-ups were made. Specimens were prepared for microtensile bond testing in accordance with the non-trimming technique and then tested either immediately or after 6-month storage in artificial saliva. Data were analyzed by ANOVA/Bonferroni tests (α = 0.05). CHX did not affect the immediate bond strength to ND or CAD (p>0.05). CHX treatment significantly lowered the loss of bond strength after 6 months seen in control bonds for ND (p<0.05), but it did not alter the bond strength of CAD (p>0.05). Application of MP on CHX-treated ND or CAD produced bonds that did not change over 6 months of storage. PMID:19363971

Effect of 2% chlorhexidine digluconate on the bond strength to normal versus caries-affected dentin.

PubMed

Komori, Paula C P; Pashley, David H; Tjäderhane, Leo; Breschi, Lorenzo; Mazzoni, Annalisa; de Goes, Mario Fernando; Wang, Linda; Carrilho, Marcela R

2009-01-01

This study evaluated the effect of 2% chlorhexidine digluconate (CHX) used as a therapeutic primer on the long-term bond strengths of two etch-and-rinse adhesives to normal (ND) and caries-affected (CAD) dentin. Forty extracted human molars with coronal carious lesions, surrounded by normal dentin, were selected for this study. The flat surfaces of two types of dentin (ND and CAD) were prepared with a water-cooled high-speed diamond disc, then acid-etched, rinsed and air-dried. In the control groups, the dentin was re-hydrated with distilled water, blot-dried and bonded with a three-step (Scotchbond Multi-Purpose-MP) or two-step (Single Bond 2-SB) etch-and-rinse adhesive. In the experimental groups, the dentin was rehydrated with 2% CHX (60 seconds), blot-dried and bonded with the same adhesives. Resin composite build-ups were made. The specimens were prepared for microtensile bond testing in accordance with the non-trimming technique, then tested either immediately or after six-months storage in artificial saliva. The data were analyzed by ANOVA/Bonferroni tests (alpha = 0.05). CHX did not affect the immediate bond strength to ND or CAD (p > 0.05). CHX treatment significantly lowered the loss of bond strength after six months as seen in the control bonds for ND (p < 0.05), but it did not alter the bond strength of CAD (p > 0.05). The application of MP on CHX-treated ND or CAD produced bonds that did not change over six months of storage.

On the strength of random fiber networks

NASA Astrophysics Data System (ADS)

Deogekar, S.; Picu, R. C.

2018-07-01

Damage accumulation and failure in random fiber networks is of importance in a variety of applications, from design of synthetic materials, such as paper and non-wovens, to accidental tearing of biological tissues. In this work we study these processes using three-dimensional models of athermal fiber networks, focusing attention on the modes of failure and on the relationship between network strength and network structural parameters. We consider network failure at small and large strains associated with the rupture of inter-fiber bonds. It is observed that the strength increases linearly with the network volume fraction and with the bond strength, while the stretch at peak stress is inversely related to these two parameters. A small fraction of the bonds rupture before peak stress and this fraction increases with increasing failure stretch. Rendering the bond strength stochastic causes a reduction of the network strength. However, heterogeneity retards damage localization and increases the stretch at peak stress, therefore promoting ductility.

Quantitative evaluation of the mechanical strength of titanium/composite bonding using laser-generated shock waves

NASA Astrophysics Data System (ADS)

Ducousso, M.; Bardy, S.; Rouchausse, Y.; Bergara, T.; Jenson, F.; Berthe, L.; Videau, L.; Cuvillier, N.

2018-03-01

Intense acoustic shock waves were applied to evaluate the mechanical strength of structural epoxy bonds between a TA6V4 titanium alloy and a 3D woven carbon/epoxy composite material. Two bond types with different mechanical strengths were obtained from two different adhesive reticulations, at 50% and 90% of conversion, resulting in longitudinal static strengths of 10 and 39 MPa and transverse strengths of 15 and 35 MPa, respectively. The GPa shock waves were generated using ns-scale intense laser pulses and reaction principles to a confined plasma expansion. Simulations taking into account the laser-matter interaction, plasma relaxation, and non-linear shock wave propagation were conducted to aid interpretation of the experiments. Good correlations were obtained between the experiments and the simulation and between different measurement methods of the mechanical strength (normalized tests vs laser-generated shock waves). Such results open the door toward certification of structural bonding.

Comparative Study of the Shear Bond Strength of Flowable Composite in Permanent Teeth Treated with Conventional Bur and Contact or Non-Contact Er:YAG Laser

PubMed Central

Parhami, Parisa; Pourhashemi, Seyed Jalal; Ghandehari, Mehdi; Mighani, Ghasem; Chiniforush, Nasim

2014-01-01

Introduction: The aim of this study was to evaluate and compare the in vitro effect of the Erbium-Doped Yttrium Aluminum Garnet (Er:YAG) laser with different radiation distances and high-speed rotary treatment on the shear bond strength of flowable composite to enamel of human permanent posterior teeth. Methods: freshly extracted human molar teeth with no caries or other surface defects were used in this study (n=45). The teeth were randomly divided into 3 groups. Group 1: treated with non-contact Er:YAG Laser and etched with Er:YAG laser, Group 2: treated with contact Er:YAG Laser and etched with Er:YAG laser, Group 3 (control): treated with diamond fissure bur and etched with acid phosphoric 37%. Then the adhesive was applied on the surafces of the teeth and polymerized using a curing light appliance. Resin cylinders were fabricated from flowable composite. Shear bond strength was tested at a crosshead speed of 0.5 mm/min. Results: The amount of Shear Bond Strength (SBS) in the 3 treatment groups was not the same (P<0.05).The group in which enamel surfaces were treated with diamond fissure bur and etched with acid (conrtol group) had the highest mean shear bond strength (19.92±4.76) and the group in which the enamel surfaces were treated with contact Er:YAG laser and etched with Er:YAG laser had the lowest mean shear bond strength (10.89±2.89). Mann-whitney test with adjusted P-value detected significant difference in shear bond strength between the control group and the other 2 groups (P < 0.05). Conclusion: It was concluded that both contact and non-contact Er:YAG laser treatment reduced shear bond strength of flowable resin composite to enamel in comparison with conventional treatment with high speed rotary. Different Er:YAG laser distance irradiations did not influence the shear bond strength of flowable composite to enamel. PMID:25653813

Defying ageing: An expectation for dentine bonding with universal adhesives?

PubMed

Zhang, Zheng-yi; Tian, Fu-cong; Niu, Li-na; Ochala, Kirsten; Chen, Chen; Fu, Bai-ping; Wang, Xiao-yan; Pashley, David H; Tay, Franklin R

2016-02-01

The present study evaluated the long-term dentine bonding effectiveness of five universal adhesives in etch-and-rinse or self-etch mode after 12 months of water-ageing. The adhesives evaluated included All-Bond Universal, Clearfil Universal Bond, Futurabond U Prime&Bond Elect and Scotchbond Universal. Microtensile bond strength and transmission electron microscopy of the resin-dentine interfaces created in human coronal dentine were examined after 24h or 12 months. Microtensile bond strength were significantly affected by bonding strategy (etch-and-rinse vs self-etch) and ageing (24h vs 12 months). All subgroups showed significantly decreased bond strength after ageing except for Prime&Bond Elect and Scotchbond Universal used in self-etch mode. All five adhesives employed in etch-and-rinse mode exhibited ultrastructural features characteristic of collagen degradation and resin hydrolysis. A previously-unobserved inside-out collagen degradation pattern was identified in hybrid layers created by 10-MDP containing adhesives (All-Bond Universal, Scotchbond Universal and Clearfil Universal Bond) in the etch-and-rinse mode, producing partially degraded collagen fibrils with intact periphery and a hollow core. In the self-etch mode, all adhesives except for Prime&Bond Elect exhibited degradation of the collagen fibrils along the thin hybrid layers. The three 10-MDP containing universal adhesives did not protect surface collagen fibrils from degradation when bonding was performed in the self-etch mode. Despite the adjunctive conclusion that bonds created by universal adhesives in the self-etch bonding mode are more resistant to decline in bond strength when compared with those bonds created using the etch-and-rinse mode, bonds created by universal adhesives are generally incapable of defying ageing. Copyright © 2015 Elsevier Ltd. All rights reserved.

Erosion and strength degradation of biomorphic SiC.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Martinez-Fernandez, J.; de Arellano-Lopez, A. R; Varela-Feria, F. M.

2004-05-01

Solid-particle-erosion studies were conducted on biomorphic SiC based on eucalyptus and pine, reaction-bonded (RB) SiC, and hot-pressed (HP) SiC. The erodents were angular SiC abrasives of average diameter 63, 143, or 390 {mu}m and the impact velocity was 100 m s{sup -1}. Impact occurred at normal incidence. Material loss in all targets occurred by brittle fracture. The biomorphic specimens eroded by formation of both lateral and radial cracks and their erosion rates were higher than both conventional SiCs. The RB SiC eroded as a classic brittle material, by formation and propagation of lateral cracks. The HP SiC, the hardest target,more » was the most erosion resistant. In erosion of the HP SiC, the abrasive particles, especially the largest ones, fragmented upon impact. The resulting dissipation of energy led to relatively low erosion rates. Flexural strength before and after erosion was measured for the biomorphic eucalyptus, RB SiC, and HP SiC. Erosion damage reduced the flexural strengths of all of the specimens. The relative strength reductions were lowest for the biomorphic eucalyptus and highest for the HP SiC. The hot-pressed SiC responded as predicted by accepted models of impact damage in brittle solids. The responses of the biomorphic and reaction-bonded SiC specimens were modeled as if they consisted of only SiC and porosity. This approximation agreed reasonably well with observed degradations of strength.« less

Role of enamel deminerlization and remineralization on microtensile bond strength of resin composite.

PubMed

Rizvi, Abbas; Zafar, Muhammad S; Al-Wasifi, Yasser; Fareed, Wamiq; Khurshid, Zohaib

2016-01-01

This study is aimed to establish the microtensile bond strength of enamel following exposure to an aerated drink at various time intervals with/without application of remineralization agent. In addition, degree of remineralization and demineralization of tooth enamel has been assessed using polarized light microscopy. Seventy extracted human incisors split into two halves were immersed in aerated beverage (cola drink) for 5 min and stored in saliva until the time of microtensile bond testing. Prepared specimens were divided randomly into two study groups; remineralizing group (n = 70): specimens were treated for remineralization using casein phosphopeptides and amorphous calcium phosphate (CPP-ACP) remineralization agent (Recaldent™; GC Europe) and control group (n = 70): no remineralization treatment; specimens were kept in artificial saliva. All specimens were tested for microtensile bond strength at regular intervals (1 h, 1 days, 2 days, 1 week, and 2 weeks) using a universal testing machine. The results statistically analyzed (P = 0.05) using two-way ANOVA test. Results showed statistically significant increase in bond strength in CPP-ACP tested group (P < 0.05) at all-time intervals. The bond strength of remineralizing group samples at 2 days (~13.64 megapascals [MPa]) is comparable to that of control group after 1 week (~12.44 MPa). CPP-ACP treatment of teeth exposed to an aerated drink provided significant increase in bond strength at a shorter interval compared to teeth exposed to saliva alone.

Effect of maleic anhydride pretreatment on tensile bond strength of a silicone soft liner to a denture base polymer.

PubMed

Demir, Hakan; Soygun, Koray; Dogan, Arife; Keskin, Selda; Dogan, Orhan Murat; Bolayir, Giray

2011-10-01

To determine the effect of resin surface treatment with dissolved maleic anhydride in butanone added into primer on the tensile bond strength between an acrylic denture base resin and a silicone soft liner. To test tensile bond strength, standard dumbbell-shaped acrylic specimens were prepared. Five experimental groups, including the control, were tested (n = 5). Maleic anhydride solutions prepared in butanone at concentrations of 1%, 5%, 10% or 20% were then mixed with 1 ml of Primo adhesive and the mixtures were applied onto the resin bonding surfaces. Silicone liner material was applied to resin surfaces in the conventional manner. Tensile bond strength of the specimens was measured in a universal testing machine. Fractured surfaces were observed under the scanning electron microscope, and resulting chemical changes with the solutions used were analyzed spectroscopically. The highest bond strength value was obtained for the group treated with 5% maleic anhydride (2.53 ± 0.48 MPa); the lowest value was for the group treated with 20% maleic anhydride (1.59 ± 0.29 MPa). Mixed failure was the dominant type seen in the experimental groups. Spectroscopic analysis showed the interaction of the anhydride carbonyl groups with the Primo primer. The treatment of resin surfaces with maleic anhydride added to Primo adhesive effectively increased bond strength between silicone soft liner and denture base resin.

Influence of previous acid etching on bond strength of universal adhesives to enamel and dentin.

PubMed

Torres, Carlos Rocha Gomes; Zanatta, Rayssa Ferreira; Silva, Tatiane Josefa; Huhtala, Maria Filomena Rocha Lima; Borges, Alessandra Bühler

2017-01-01

The objective of this study was to evaluate the effect of acid pretreatment on the bond strength of composite resin bonded to enamel and dentin with 2 different universal self-etching adhesives. The null hypothesis was that the acid treatment performed prior to adhesive application would not significantly change the bond strength to enamel or dentin for either universal adhesive tested. A sample of 112 bovine incisors were selected and embedded in acrylic resin. Half were ground until a flat enamel surface was obtained, and the other half were polished until a 6 × 6-mm area of dentin was exposed, resulting into 2 groups (n = 56). The enamel and dentin groups were divided into 2 subgroups according to the adhesive system applied: Futurabond U or Scotchbond Universal. Each of these subgroups was divided into 2 additional subgroups (n = 14); 1 subgroup received phosphoric acid pretreatment, and 1 subgroup did not. The bond strength was assessed with a microtensile test. Data from enamel and dentin specimens were analyzed separately using 1-way analysis of variance. The acid pretreatment did not significantly change the bond strength of the adhesives tested, either to enamel (P = 0.4161) or to dentin (P = 0.4857). The acid etching pretreatment did not affect the bond strength to dentin and enamel when the tested universal multipurpose adhesive systems were used.

Effects of femtosecond laser and other surface treatments on the bond strength of metallic and ceramic orthodontic brackets to zirconia

PubMed Central

García-Sanz, Verónica; Bellot-Arcís, Carlos; Mendoza-Yero, Omel; Doñate-Buendía, Carlos; Montero, Javier; Albaladejo, Alberto

2017-01-01

Femtosecond laser has been proposed as a method for conditioning zirconia surfaces to boost bond strength. However, metallic or ceramic bracket bonding to femtosecond laser-treated zirconia surfaces has not been tested. This study compared the effects of four conditioning techniques, including femtosecond laser irradiation, on shear bond strength (SBS) of metallic and ceramic brackets to zirconia.Three hundred zirconia plates were divided into five groups: 1) control (C); 2) sandblasting (APA); 3) silica coating and silane (SC); 4) femtosecond laser (FS); 5) sandblasting followed by femtosecond laser (APA+SC). A thermal imaging camera measured temperature changes in the zirconia during irradiation. Each group was divided into 2 subgroups (metallic vs ceramic brackets). SBS was evaluated using a universal testing machine. The adhesive remnant index (ARI) was registered and surfaces were observed under SEM. Surface treatment and bracket type significantly affected the bracket-zirconia bond strength. SBS was significantly higher (p<0.001) for ceramic brackets in all groups (APA+FS > APA > FS > SC > control) than metallic brackets (APA+FS > FS > SC > APA > control). For metallic brackets, groups SC (5.99 ± 1.86 MPa), FS (6.72 ± 2.30 MPa) and APA+FS (7.22 ± 2.73 MPa) reported significantly higher bond strengths than other groups (p < 0.05). For ceramic brackets, the highest bond strength values were obtained in groups APA (25.01 ± 4.45 MPa), FS (23.18 ± 6.51 MPa) and APA+FS (29.22 ± 8.20 MPa).Femtosecond laser enhances bond strength of ceramic and metallic brackets to zirconia. Ceramic brackets provide significantly stronger adhesion than metallic brackets regardless of the surface treatment method. PMID:29049418

Bond strength of orthodontic light-cured resin-modified glass ionomer cement.

PubMed

Cheng, Hsiang Yu; Chen, Chien Hsiu; Li, Chuan Li; Tsai, Hung Huey; Chou, Ta Hsiung; Wang, Wei Nan

2011-04-01

The purpose of this study was to compare the bond strengths and debonded interfaces achieved with light-cured resin-modified glass ionomer cement (RMGIC) and conventional light-cured composite resin. In addition, the effects of acid etching and water contamination were examined. One hundred human premolars were randomly divided into five equal groups. The mini Dyna-lock upper premolar bracket was selected for testing. The first four groups were treated with light-cured RMGIC with or without 15 per cent phosphoric acid-etching treatment and with or without water contamination preceding bracket bonding. The control samples were treated with the conventional light-cured Transbond composite resin under acid etching and without water contamination. Subsequently, the brackets were debonded by tensile force using an Instron machine. The modified adhesive remnant index (ARI) scores were assigned to the bracket base of the debonded interfaces using a scanning electron microscope. The bond strength and modified ARI scores were determined and analysed statistically by one-way analysis of variance and chi-square test. Under all four conditions, the bond strength of the light-cure RMGIC was equal to or higher than that of the conventional composite resin. The highest bond strength was achieved when using RMGIC with acid etching but without water contamination. The modified ARI scores were 2 for Fuji Ortho LC and 3 for Transbond. No enamel detachment was found in any group. Fifteen per cent phosphoric acid etching without moistening the enamel of Fuji Ortho LC provided the more favourable bond strength. Enamel surfaces, with or without water contamination and with or without acid etching, had the same or a greater bond strength than Transbond.

Comparative study of the shear bond strength of various veneering materials on grade II commercially pure titanium

PubMed Central

Lee, Eun-Young; Jun, Sul-Gi; Wright, Robert F.

2015-01-01

PURPOSE To compare the shear bond strength of various veneering materials to grade II commercially pure titanium (CP-Ti). MATERIALS AND METHODS Thirty specimens of CP-Ti disc with 9 mm diameter and 10 mm height were divided into three experimental groups. Each group was bonded to heat-polymerized acrylic resin (Lucitone 199), porcelain (Triceram), and indirect composite (Sinfony) with 7 mm diameter and 2 mm height. For the control group (n=10), Lucitone 199 were applied on type IV gold alloy castings. All samples were thermocycled for 5000 cycles in 5-55℃ water. The maximum shear bond strength (MPa) was measured with a Universal Testing Machine. After the shear bond strength test, the failure mode was assessed with an optic microscope and a scanning electron microscope. Statistical analysis was carried out with a Kruskal-Wallis Test and Mann-Whitney Test. RESULTS The mean shear bond strength and standard deviations for experimental groups were as follows: Ti-Lucitone 199 (12.11 ± 4.44 MPa); Ti-Triceram (11.09 ± 1.66 MPa); Ti-Sinfony (4.32 ± 0.64 MPa). All of these experimental groups showed lower shear bond strength than the control group (16.14 ± 1.89 MPa). However, there was no statistically significant difference between the Ti-Lucitone 199 group and the control group, and the Ti-Lucitone 199 group and the Ti-Triceram group. Most of the failure patterns in all experimental groups were adhesive failures. CONCLUSION The shear bond strength of veneering materials such as heat-polymerized acrylic resin, porcelain, and indirect composite to CP-Ti was compatible to that of heatpolymerized acrylic resin to cast gold alloy. PMID:25722841

Fiber post cementation strategies: effect of mechanical cycling on push-out bond strength and cement polymerization stress.

PubMed

Bergoli, Cesar Dalmolin; Amaral, Marina; Boaro, Leticia Cristina; Braga, Roberto Ruggiero; Valandro, Luiz Felipe

2012-08-01

To evaluate the effect of mechanical cycling and cementation strategies on the push-out bond strength between fiber posts and root dentin and the polymerization stresses produced using three resin cements. Eighty bovine mandibular teeth were sectioned to a length of 16 mm, prepared to 12 mm, and embedded in self-curing acrylic resin. The specimens were then distributed into 8 groups (n = 10): Gr1 - Scotchbond Multi Purpose + RelyX ARC; Gr2 - Scotchbond Multi Purpose + RelyX ARC + mechanical cycling; Gr3 - AdheSE + Multilink Automix; Gr4 - AdheSE + Multilink Automix + mechanical cycling; Gr5 - phosphoric acid + RelyX U100 (self-adhesive cement); Gr6 - phosphoric acid+ RelyX U100 + mechanical cycling; Gr7 - RelyX U100; Gr8 - RelyX U100 + mechanical cycling. The values obtained from the push-out bond strength test were submitted to two-way ANOVA and Tukey's test (p = 0.05), while the values obtained from the polymerization stress test were subjected to one-way ANOVA and Tukey's test (α = 0.05). Mechanical cycling did not affect the bond strength values (p = 0.236), while cementation strategies affected the push-out bond strength (p < 0.001). Luting with RelyX U100 and Scotch Bond Multi Purpose + RelyX ARC yielded higher push-out bond strength values. The polymerization stress results were affected by the factor "cement" (p = 0.0104): the self-adhesive cement RelyX U100 exhibited the lowest values, RelyX ARC resulted in the highest values, while Multilink Automix presented values statistically similar to the other two cements. The self-adhesive cement appears to be a good alternative for luting fiber posts due to the high push-out bond strengths and lower polymerization stress values.

Recycling stainless steel orthodontic brackets with Er:YAG laser - An environmental scanning electron microscope and shear bond strength study.

PubMed

Chacko, Prince K; Kodoth, Jithesh; John, Jacob; Kumar, Kishore

2013-07-01

TO DETERMINE THE EFFICIENCY OF ERBIUM: Yttrium aluminum garnet (Er:YAG) laser with Environmental Scanning Electron Microscope (ESEM) and shear bond strength analysis as a method of recycling stainless steel orthodontic brackets and compare with other methods of recycling. Eighty samples of extracted premolar teeth bonded to SS brackets were tested for rebonded shear bond strength after recycling by four methods and compared with a control group of 20 samples. These 80 samples were randomized into four groups which were recycled by four methods, namely, sandblasting, thermal method, adhesive grinding by tungsten carbide bur, and Er: YAG laser method. After recycling, ESEM and shear bond strength analysis were used to analyze the efficiency of the recycling methods. ER: YAG laser group was found to be having the greatest bond strength among the recycled brackets (8.33±2.51 followed by the sandblasting at 6.12±1.12 MPa, thermal and electropolishing at 4.44±0.95 MPa, and lastly the adhesive grinding method at 3.08±1.07 MPa. The shear bond strength of Er: YAG laser group was found to be having no statistically significant difference with that of the control group (P>0.05 and had statistical signifance with sandblasting, thermal and electropolishing and adhesive grinding groups at P>0.001. ESEM analysis showed complete removal of adhesive from the brackets recycled with Er: YAG laser which mimicked that of the control group. ER: YAG laser (2940 nm) was found to be the most efficient method for recycling, followed by the sandblasting, thermal, and the tungsten carbide methods, which had the least shear bond strength value and is not fit for clinical usage.

Effects of femtosecond laser and other surface treatments on the bond strength of metallic and ceramic orthodontic brackets to zirconia.

PubMed

García-Sanz, Verónica; Paredes-Gallardo, Vanessa; Bellot-Arcís, Carlos; Mendoza-Yero, Omel; Doñate-Buendía, Carlos; Montero, Javier; Albaladejo, Alberto

2017-01-01

Femtosecond laser has been proposed as a method for conditioning zirconia surfaces to boost bond strength. However, metallic or ceramic bracket bonding to femtosecond laser-treated zirconia surfaces has not been tested. This study compared the effects of four conditioning techniques, including femtosecond laser irradiation, on shear bond strength (SBS) of metallic and ceramic brackets to zirconia.Three hundred zirconia plates were divided into five groups: 1) control (C); 2) sandblasting (APA); 3) silica coating and silane (SC); 4) femtosecond laser (FS); 5) sandblasting followed by femtosecond laser (APA+SC). A thermal imaging camera measured temperature changes in the zirconia during irradiation. Each group was divided into 2 subgroups (metallic vs ceramic brackets). SBS was evaluated using a universal testing machine. The adhesive remnant index (ARI) was registered and surfaces were observed under SEM. Surface treatment and bracket type significantly affected the bracket-zirconia bond strength. SBS was significantly higher (p<0.001) for ceramic brackets in all groups (APA+FS > APA > FS > SC > control) than metallic brackets (APA+FS > FS > SC > APA > control). For metallic brackets, groups SC (5.99 ± 1.86 MPa), FS (6.72 ± 2.30 MPa) and APA+FS (7.22 ± 2.73 MPa) reported significantly higher bond strengths than other groups (p < 0.05). For ceramic brackets, the highest bond strength values were obtained in groups APA (25.01 ± 4.45 MPa), FS (23.18 ± 6.51 MPa) and APA+FS (29.22 ± 8.20 MPa).Femtosecond laser enhances bond strength of ceramic and metallic brackets to zirconia. Ceramic brackets provide significantly stronger adhesion than metallic brackets regardless of the surface treatment method.

Stability Mechanisms of a Thermophilic Laccase Probed by Molecular Dynamics

PubMed Central

Christensen, Niels J.; Kepp, Kasper P.

2013-01-01

Laccases are highly stable, industrially important enzymes capable of oxidizing a large range of substrates. Causes for their stability are, as for other proteins, poorly understood. In this work, multiple-seed molecular dynamics (MD) was applied to a Trametes versicolor laccase in response to variable ionic strengths, temperatures, and glycosylation status. Near-physiological conditions provided excellent agreement with the crystal structure (average RMSD ∼0.92 Å) and residual agreement with experimental B-factors. The persistence of backbone hydrogen bonds was identified as a key descriptor of structural response to environment, whereas solvent-accessibility, radius of gyration, and fluctuations were only locally relevant. Backbone hydrogen bonds decreased systematically with temperature in all simulations (∼9 per 50 K), probing structural changes associated with enthalpy-entropy compensation. Approaching T opt (∼350 K) from 300 K, this change correlated with a beginning “unzipping” of critical β-sheets. 0 M ionic strength triggered partial denucleation of the C-terminal (known experimentally to be sensitive) at 400 K, suggesting a general salt stabilization effect. In contrast, F− (but not Cl−) specifically impaired secondary structure by formation of strong hydrogen bonds with backbone NH, providing a mechanism for experimentally observed small anion destabilization, potentially remedied by site-directed mutagenesis at critical intrusion sites. N-glycosylation was found to support structural integrity by increasing persistent backbone hydrogen bonds by ∼4 across simulations, mainly via prevention of F− intrusion. Hydrogen-bond loss in distinct loop regions and ends of critical β-sheets suggest potential strategies for laboratory optimization of these industrially important enzymes. PMID:23658618

Push-off tests and strength evaluation of joints combining shrink fitting with bonding

NASA Astrophysics Data System (ADS)

Yoneno, Masahiro; Sawa, Toshiyuki; Shimotakahara, Ken; Motegi, Yoichi

1997-03-01

Shrink fitted joints have been used in mechanical structures. Recently, joints combining shrink fitting with anaerobic adhesives bonded between the shrink fitted surfaces have been appeared in order to increase the joint strength. In this paper, push-off test was carried out on strength of joints combining shrink fitting with bonding by material testing machine. In addition, the push-off strength of shrink fitting joints without an anaerobic adhesive was also measured. In the experiments, the effects of the shrinking allowance and the outer diameter of the rings on the joint strength are examined. The interface stress distribution in bonded shrink fitted joints subjected to a push-off load is analyzed using axisymmetrical theory of elasticity as a four-body contact problem. Using the interface stress distribution, a method for estimating joint strength is proposed. The experimental results are in a fairly good agreement with the numerical results. It is found that the strength of combination joints is greater than that of shrink fitted joints.

Fracture strength testing of crowns made of CAD/CAM composite resins.

PubMed

Okada, Ryota; Asakura, Masaki; Ando, Akihiro; Kumano, Hirokazu; Ban, Seiji; Kawai, Tatsushi; Takebe, Jun

2018-03-28

The purpose of this study was to ascertain whether computer aided design/computer aided manufacturing (CAD/CAM) composite resin crowns have sufficient strength to withstand the bite force of the molar teeth. The null hypothesis was that the fracture strength of CAD/CAM composite resin crowns is lower than the average maximum bite force of the molar tooth. The crowns, which shape is the right maxillary first molar, were fabricated using four CAD/CAM blanks made of composite resins (Block HC: HC, KZR-CAD HR: HR, KZR-CAD HR2: HR2, Avencia Block: AVE) and one CAD/CAM blank made of lithium disilicate glass-ceramic (IPS e.max CAD: IPS), which was used as a control. Fracture strength of fabricated crowns bonded to metal abutment and biaxial flexural strength of the materials were evaluated. The results of fracture strength test and biaxial flexural strength test showed different tendencies. The fracture strength of CAD/CAM composite resin crowns except HC ranged from 3.3kN to 3.9kN, and was similar to that of IPS (3.3kN). In contrast, biaxial flexural strength of CAD/CAM composite resins ranged from 175MPa to 247MPa, and was significantly lower than that of IPS (360MPa). All CAD/CAM composite resin crowns studied presented about 3-4 times higher fracture strength than the average maximum bite force of the molar tooth (700-900N), which result leads to the conclusion that CAD/CAM composite resin crowns would have sufficient strength to withstand the bite force of the molar teeth. Copyright © 2017 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

Effect of water storage on the silanization in porcelain repair strength.

PubMed

Berry, T; Barghi, N; Chung, K

1999-06-01

This study examined the long-term water storage affect of silanization on shear bond strength of composite resin to porcelain. One hundred and sixty square-shaped specimens were fabricated and sanded flat sequentially with silicone carbide papers. The specimens were then placed into four groups and 16 subgroups of 10 specimens each randomly. Four commercially available silane systems, two one-mix and two two-mix, were tested in this study. Teflon tubes with an internal diameter of 2.97 mm and 2 mm in height were filled with a dual cure composite resin (Mirage FLC), placed on the silanated surfaces and light-cured for 120 s. Specimens were stored in room temperature water and subjected to shear bond strength testing after 24 h, 1 week, 1 month and 3 month periods of immersion. An Instron Universal testing machine with a crosshead speed of 0.5 mm/min was used for the testing. The mean values of the shear bond strengths ranged from 4.38 MPa (24-h period) to 23.90 MPa (3-month period). ANOVA and Scheffe' tests were used to analyse data with confidence level at 95%. All groups recorded an increase in bond strength after one week as compared with the 24-h period (P<0.05). With the exception of a one-mix system, all systems showed significantly higher bond strength at 3 weeks as compared with the 24-h and 1-week water storage periods. In conclusion, bond strength of composite resin to porcelain resulting from silanization of porcelain increased during the experimental period. The bond strength also varied for different silanes used in this study.

Repair bond strength of nanohybrid composite resins with a universal adhesive

PubMed Central

Altinci, Pinar; Mutluay, Murat; Tezvergil-Mutluay, Arzu

2018-01-01

Abstract Objective: To investigate the repair bond strength of fresh and aged nanohybrid and hybrid composite resins using a universal adhesive (UA). Materials and methods: Fresh and aged substrates were prepared using two nanohybrid (Venus Pearl, Heraus Kulzer; Filtek Supreme XTE, 3 M ESPE) and one hybrid (Z100, 3 M ESPE) composite resin, and randomly assigned to different surface treatments: (1) no treatment (control), (2) surface roughening with 320-grit (SR), (3) SR + UA (iBOND, Heraus Kulzer), (4) SR + Silane (Signum, Ceramic Bond I, Heraeus Kulzer) + UA, (5) SR + Sandblasting (CoJet, 3 M ESPE) + Silane + UA. After surface treatment, fresh composite resin was added to the substrates at 2 mm layer increments to a height of 5 mm, and light cured. Restored specimens were water-stored for 24 h and sectioned to obtain 1.0 × 1.0 mm beams (n = 12), and were either water-stored for 24 h at 37 °C, or water-stored for 24 h, and then thermocycled for 6000 cycles before microtensile bond strength (µTBS) testing. Data were analyzed with ANOVA and Tukey’s HSD tests (p = .05). Results: Combined treatment of SR, sandblasting, silane and UA provided repair bond strength values comparable to the cohesive strength of each tested resin material (p < .05). Thermocycling significantly reduced the cohesive strength of the composite resins upto 65% (p < .05). Repair bond strengths of UA-treated groups were more stable under thermocycling. Conclusions: Universal adhesive application is a reliable method for composite repair. Sandblasting and silane application slightly increases the repair strength for all substrate types. PMID:29250576

Repair bond strength of nanohybrid composite resins with a universal adhesive.

PubMed

Altinci, Pinar; Mutluay, Murat; Tezvergil-Mutluay, Arzu

2018-01-01

Objective: To investigate the repair bond strength of fresh and aged nanohybrid and hybrid composite resins using a universal adhesive (UA). Materials and methods: Fresh and aged substrates were prepared using two nanohybrid (Venus Pearl, Heraus Kulzer; Filtek Supreme XTE, 3 M ESPE) and one hybrid (Z100, 3 M ESPE) composite resin, and randomly assigned to different surface treatments: (1) no treatment (control), (2) surface roughening with 320-grit (SR), (3) SR + UA (iBOND, Heraus Kulzer), (4) SR + Silane (Signum, Ceramic Bond I, Heraeus Kulzer) + UA, (5) SR + Sandblasting (CoJet, 3 M ESPE) + Silane + UA. After surface treatment, fresh composite resin was added to the substrates at 2 mm layer increments to a height of 5 mm, and light cured. Restored specimens were water-stored for 24 h and sectioned to obtain 1.0 × 1.0 mm beams ( n  = 12), and were either water-stored for 24 h at 37 °C, or water-stored for 24 h, and then thermocycled for 6000 cycles before microtensile bond strength (µTBS) testing. Data were analyzed with ANOVA and Tukey's HSD tests ( p  = .05). Results: Combined treatment of SR, sandblasting, silane and UA provided repair bond strength values comparable to the cohesive strength of each tested resin material ( p  < .05). Thermocycling significantly reduced the cohesive strength of the composite resins upto 65% ( p  < .05). Repair bond strengths of UA-treated groups were more stable under thermocycling. Conclusions: Universal adhesive application is a reliable method for composite repair. Sandblasting and silane application slightly increases the repair strength for all substrate types.

Evaluation of flexural, diametral tensile, and shear bond strength of composite repairs.

PubMed

Imbery, T A; Gray, T; DeLatour, F; Boxx, C; Best, A M; Moon, P C

2014-01-01

Repairing composite restorations may be a more conservative treatment than replacing the entire restoration. The objective of this in vitro study was to determine the best repair method by measuring flexural, diametral tensile, and shear bond strength of repaired composites in which the surfaces were treated with chemical primers (Add & Bond or Silane Bond Enhancer), a bonding agent (Optibond Solo Plus [OBSP]), or mechanical retention with a bonding agent. Filtek Supreme Ultra shade B1B was placed in special molds to fabricate specimens that served to test the flexural, diametral tensile, or shear strength of the inherent resin substrate. The same molds were modified to make specimens for testing repair strength of the resin. Repairs were made immediately or after aging in deionized water at 37°C for seven days. All repair sites were finished with coarse Sof-Lex discs to simulate finishing new restorations or partially removing aged restorations. Repair surfaces were treated with one of the following: 1) phosphoric-acid etching and OBSP; 2) Add & Bond; 3) phosphoric-acid etching, Silane Bond Enhancer, and OBSP; or 4) quarter round bur, phosphoric-acid etching, and OBSP. Specimens were placed back in the original molds to fabricate specimens for diametral tensile or flexural testing or in an Ultradent jig to make specimens for shear bond testing. Composite resin in shade B5B was polymerized against the treated surfaces to make repairs. Two negative control groups for the three testing methods consisted of specimens in which repairs were made immediately or after aging without any surface treatments. Controls and experimental repairs were aged (water 37°C, 24 hours) before flexural, diametral tensile, or shear testing in an Instron Universal testing machine at a crosshead speed of 0.5 mm/min. Experimental flexural repair strengths ranged from 26.4% to 88.6% of the inherent substrate strength. Diametral tensile repair strengths ranged from 40% to 80% of the inherent substrate strength, and shear bond strength repairs ranged from 56% to 102%. Geometric means were statistically analyzed with two-way analysis of variance on their log-transformed values. Significant differences were determined using Tukey honestly significant difference (p<0.05). Depending on the mechanical property being tested, surface treatments produced different results. OBSP produced more consistent results than chemical primers.

Micro-oxidation treatment to improve bonding strength of Sr and Na co-substituted hydroxyapatite coatings for carbon/carbon composites

NASA Astrophysics Data System (ADS)

Zhang, Leilei; Li, Hejun; Li, Kezhi; Zhang, Yulei; Liu, Shoujie; Guo, Qian; Li, Shaoxian

2016-08-01

To improve the bonding strength of Sr and Na co-substituted hydroxyapatite (SNH) coatings for carbon/carbon composites, carbon/carbon composites are surface modified by micro-oxidation treatment. The micro-oxidation treatment could generate large number of pores containing oxygenic functional groups on the surface of carbon/carbon composites. SNH is nucleated on the inwall of the pores and form a flaky shape coating with 10-50 nm in thickness and 200-900 nm in width. The bonding strength between SNH coating and carbon/carbon composites increases from 4.27 ± 0.26 MPa to 10.57 ± 0.38 MPa after the micro-oxidation treatment. The promotion of bonding strength is mainly attributed to the pinning effect caused by the pores and chemical bonding generated by the oxygenic functional groups.

Molecular geometry as a source of chemical information. 5. Substituent effect on proton transfer in para-substituted phenol complexes with fluoride--a B3LYP/6-311+G study.

PubMed

Krygowski, Tadeusz M; Szatyłowicz, Halina; Zachara, Joanna E

2005-01-01

The simplified model system [p-X-PhO...H...F](-), where -X are -NO, -NO(2), -CHO, -H, -CH(3), -OCH(3), and -OH, with various O...F distance was used to simulate the wide range of the H-bond strength. Structural changes due to variation of the substituent as well as the H-bond strength are well monitored by the changes in the aromaticity index HOMA and by two empirical measures of the H-bond strength-the (1)H NMR chemical shift of proton involved and the C-O bond length. Changes in H-bonding strengths and the position of proton transfer while shortening the O...F distance are well described by the Hammett equation.

Fracture toughness, diametrical strength, and fractography of amalgam and of amalgam to amalgam bonds.

PubMed

Bapna, M S; Mueller, H J

1993-01-01

Chevron-notch fracture toughness, diametrical tensile strength and fractography were evaluated for bulk amalgams and for bonds formed between new and 1-day-old amalgams of the same type. Three types of bonded specimens were prepared: 1) by mechanically roughening the 1-day-old amalgam with 600-grit paper; 2) using a new mercury-rich amalgam; and 3) using a bonding resin, either 4-META or a phosphate ester monomer. Similar values in bond properties were obtained with all bonding techniques for two commercial dispersed-phase bonded amalgams, one of which contained palladium; however, bulk fracture toughness of the palladium-containing amalgam was significantly less than for the palladium-free amalgam. This result reveals that the bonding of amalgam to amalgam, at least for these two amalgams, is a surface-related phenomenon, and thus, the traditional reporting of bonding properties as a percentage of bulk properties loses meaning. Short-rod geometry was more representative of the interfacial bond properties since these samples fractured within the interfacial bonds, while diametrical strength samples often fractured slightly away from the interface. The use of bonding resins did not improve bond fracture toughness for either amalgam, while the diametrical strength improved for one of the amalgams. The use of mercury-rich amalgam significantly improved the fracture toughness over all other techniques for one amalgam while proving to be similar to a 600-grit preparation for the second amalgam.(ABSTRACT TRUNCATED AT 250 WORDS)

Bond strength of resin-modified glass ionomer restorative materials using a no-rinse conditioner.

PubMed

Suihkonen, Rian W; Vandewalle, Kraig S; Dossett, Jon M

2012-01-01

A paste-paste resin-modified glass ionomer (RMGI) restorative material has been introduced recently with a new conditioner that requires no rinsing. The purpose of this study was to compare the shear bond strength of an encapsulated RMGI (Fuji II LC) and a new paste-paste RMGI (Fuji Filling LC) to dentin conditioned with 20% polyacrylic acid (Cavity Conditioner), a new no-rinse conditioner (Self Conditioner,), or no conditioner. Mounted human third molars were flattened and the dentin surface was conditioned. The RMGI restorative materials were mixed and incrementally inserted into a mold and photocured. The specimens were loaded until failure in a universal testing machine after 24 hours of storage in distilled water. Fuji II LC had significantly greater bond strength to dentin than Fuji Filling LC. The use of Cavity Conditioner or Self Conditioner resulted in bond strengths that were not significantly different from each other; however, both produced greater bond strengths than those in the non-conditioned groups.

Shear bond strength of one-step self-etch adhesives to enamel: effect of acid pretreatment.

PubMed

Poggio, Claudio; Scribante, Andrea; Della Zoppa, Federica; Colombo, Marco; Beltrami, Riccardo; Chiesa, Marco

2014-02-01

The purposes of this study were to evaluate the effect of surface pretreatment with phosphoric acid on the enamel bond strength of four-one-step self-etch adhesives with different pH values. One hundred bovine permanent mandibular incisors were used. The materials used in this study included four-one-step self-etch adhesives with different pH values: Adper(™) Easy Bond Self-Etch Adhesive (ph = 0,8-1), Futurabond NR (ph = 1,4), G-aenial Bond (ph = 1,5), Clearfil(3) S Bond (ph = 2,7). One two-step self-etch adhesive (Clearfil SE Bond/ph = 0,8-1) was used as control. The teeth were assigned into two subgroups according to bonding procedure. In the first subgroup (n = 50), no pretreatment agent was applied. In the second subgroup (n = 50), etching was performed using 37% phosphoric acid for 30 s. After adhesive systems application, a nanohybrid composite resin was inserted into the enamel surface. The specimens were placed in a universal testing machine (Model 3343, Instron Corp., Canton, Mass., USA). After the testing procedure, the fractured surfaces were examined with an optical microscope at a magnification of 10× to determine failure modes. The adhesive remnant index (ARI) was used to assess the amount of adhesive left on the enamel surface. Descriptive statistics of the shear bond strength and frequency distribution of ARI scores were calculated. Enamel pretreatment with phosphoric acid significantly increased bond strength values of all the adhesives tested. No significant differences in bond strength were detected among the four different one-step self-etch adhesives with different pH. Two-step self-etch adhesive showed the highest bond strength. © 2013 John Wiley & Sons A/S.

Influence of the number of cycles on shear fatigue strength of resin composite bonded to enamel and dentin using dental adhesives in self-etching mode.

PubMed

Tsujimoto, Akimasa; Barkmeier, Wayne W; Erickson, Robert L; Takamizawa, Toshiki; Latta, Mark A; Miyazaki, Masashi

2018-01-30

The influence of the number of cycles on shear fatigue strength to enamel and dentin using dental adhesives in self-etch mode was investigated. A two-step self-etch adhesive and two universal adhesives were used to bond to enamel and dentin in self-etch mode. Initial shear bond strength and shear fatigue strength to enamel and dentin using the adhesive in self-etch mode were determined. Fatigue testing was used with 20 Hz frequency and cycling periods of 50,000, 100,000 and 1,000,000 cycles, or until failure occurred. For each of the cycling periods, there was no significant difference in shear fatigue strength across the cycling periods for the individual adhesives. Differences in shear fatigue strength were found between the adhesives within the cycling periods. Regardless of the adhesive used in self-etch mode for bonding to enamel or dentin, shear fatigue strength was not influenced by the number of cycles used for shear fatigue strength testing.

[Effect of vacuum deposition technology on the metal-porcelain bond strength of a new type of CO-CR ceramic and framework dental alloy].

PubMed

Wu, Jun-ling; Chao, Yong-lie; Ji, Ping; Gao, Xu

2007-10-01

To investigate the effect of a new engineering technique of vacuum deposition-plasma magnetron reactive sputter deposition technique on the metal-porcelain bond strength of a new type of Co-Cr ceramic and framework dental alloy. Before porcelain painted on the specimens, the standardized metal strips made from DA9-4 dental alloy were coated with a thin Al2O3 ceramic film by plasma magnetron reactive sputter deposition technique. The conformation, structure and thickness of the ceramic film were analyzed. The specimens for three-point bending test made from DA9-4 alloy and VMK95 porcelain were used for metal-porcelain bond strength measurement, in the same time the interface of metal-porcelain and element distribution were also observed. The flexural bonding strength of metal-porcelain of sputtering group and control group were (180.55+/-16.45) MPa and (143.80+/-24.49) MPa. The flexural bonding strength of metal-porcelain of sputtering group was higher than control group significantly through statistical analysis (P<0.01). The plasma magnetron reactive sputter deposition technique has a positive effect in improving the bonding strength of DA9-4 dental alloy and ceramic.

Effect of amalgam corrosion products in non-discolored dentin on the bond strength of replaced composite resin

PubMed Central

Ghavamnasiri, Marjaneh; Eslami, Samaneh; Ameri, Hamide; Chasteen, Joseph E.; Majidinia, Sara; Moghadam, Fatemeh Velayaty

2015-01-01

Objectives: To evaluate the effect of amalgam corrosion products in non-discolored dentin on the bond strength of replaced composite resin. Materials and Methods: One hundred and sixty-one Class I cavities were prepared on extracted premolars and divided into seven groups. Group 1: Light-cured composite; Groups 2, 3, and 4: Amalgam stored in 37°C normal saline for respectively 1, 3, and 6 months and then replaced with composite leaving the cavity walls intact. Groups 5, 6, and 7: Identical to Groups 2, 3, and 4, except the cavity walls were extended 0.5 mm after amalgam removal. Eighteen specimens from each group were selected for shear bond strength testing, while on remaining five samples, elemental microanalysis was conducted. Data were analyzed using Mann-Whitney and Freidman (α = 0.05). Results: There was a significant difference between Groups 1 and 4 and also between Group 1 and Groups 5, 6, and 7. However, Groups 1, 2, and 3 showed no significant difference regarding bond strength. Bond strengths of Group 4 was significantly less than Groups 2 and 3. However, Groups 5, 6, and 7 showed similar bond strength. There was no difference among all groups in terms of metal elements at any storage times. PMID:25657522

The effect of ultrafast fiber laser application on the bond strength of resin cement to titanium.

PubMed

Ates, Sabit Melih; Korkmaz, Fatih Mehmet; Caglar, Ipek Satıroglu; Duymus, Zeynep Yeşil; Turgut, Sedanur; Bagis, Elif Arslan

2017-07-01

The purpose of this study was to investigate the effect of ultrafast fiber laser treatment on the bond strength between titanium and resin cement. A total of 60 pure titanium discs (15 mm × 2 mm) were divided into six test groups (n = 10) according to the surface treatment used: group (1) control, machining; group (2) grinding with a diamond bur; group (3) ultrafast fiber laser application; group (4) resorbable blast media (RBM) application; group (5) electro-erosion with copper; and group (6) sandblasting. After surface treatments, resin cements were applied to the treated titanium surfaces. Shear bond strength testing of the samples was performed with a universal testing machine after storing in distilled water at 37 °C for 24 h. One-way ANOVA and Tukey's HSD post hoc test were used to analyse the data (P < 0.05). The highest bond strength values were observed in the laser application group, while the lowest values were observed in the grinding group. Sandblasting and laser application resulted in significantly higher bond strengths than control treatment (P < 0.05). Ultrafast fiber laser treatment and sandblasting may improve the bond strength between resin cement and titanium.

Effect of Cigarette Smoke on Resin Composite Bond Strength to Enamel and Dentin Using Different Adhesive Systems.

PubMed

Theobaldo, J D; Catelan, A; Rodrigues-Filho, U; Marchi, G M; Lima, Danl; Aguiar, Fhb

2016-01-01

To evaluate the microshear bond strength of composite resin restorations in dental blocks with or without exposure to cigarette smoke. Eighty bovine dental blocks were divided into eight groups (n=10) according to the type of adhesive (Scotchbond Multi-Purpose, 3M ESPE, St Paul, MN, USA [SBMP]; Single Bond 2, 3M ESPE [SB]; Clearfil SE Bond, Kuraray Medical Inc, Okayama, Japan [CSEB]; Single Bond Universal, 3M ESPE [SBU]) and exposure to smoke (no exposure; exposure for five days/20 cigarettes per day). The adhesive systems were applied to the tooth structure, and the blocks received a composite restoration made using a matrix of perforated pasta. Data were statistically analyzed using analysis of variance and Tukey test (α<0.05). For enamel, there was no difference between the presence or absence of cigarette smoke (p=0.1397); however, there were differences among the adhesive systems (p<0.001). CSEB showed higher values and did not differ from SBU, but both were statistically different from SB. The SBMP showed intermediate values, while SB demonstrated lower values. For dentin, specimens subjected to cigarette smoke presented bond strength values that were lower when compared with those not exposed to smoke (p<0.001). For the groups without exposure to cigarette smoke, CSEB showed higher values, differing from SBMP. SB and SBU showed intermediary values. For the groups with exposure to cigarette smoke, SBU showed values that were higher and statistically different from SB and CSEB, which presented lower values of bond strength. SBMP demonstrated an intermediate value of bond strength. The exposure of dentin to cigarette smoke influenced the bonding strength of adhesives, but no differences were noted in enamel.

Effect of acid and laser etching on shear bond strength of conventional and resin-modified glass-ionomer cements to composite resin.

PubMed

Navimipour, Elmira Jafari; Oskoee, Siavash Savadi; Oskoee, Parnian Alizadeh; Bahari, Mahmoud; Rikhtegaran, Sahand; Ghojazadeh, Morteza

2012-03-01

Success in sandwich technique procedures can be achieved through an acceptable bond between the materials. The aim of this study was to compare the effect of 35% phosphoric acid and Er,Cr:YSGG laser on shear bond strength of conventional glass-ionomer cement (GIC) and resin-modified glass-ionomer cement (RMGIC) to composite resin in sandwich technique. Sixty-six specimens were prepared from each type of glass-ionomer cements and divided into three treatment groups as follows: without pretreatment, acid etching by 35% phosphoric acid for 15 s, and 1-W Er,Cr:YSGG laser treatment for 15 s with a 600-μm-diameter tip aligned perpendicular to the target area at a distance of 1 mm from the surface. Energy density of laser irradiation was 17.7 J/cm(2). Two specimens in each group were prepared for evaluation under a scanning electron microscope (SEM) after surface treatment and the remainder underwent bonding procedure with a bonding agent and composite resin. Then the shear bond strength was measured at a crosshead speed of 0.5 mm/min. Two-factor analysis of variance and post-hoc Tukey test showed that the cement type, surface treatment method, and the interaction of these two factors significantly affect the shear bond strength between glass-ionomer cements and composite resin (p < 0.05). Surface treatment with phosphoric acid or Er,Cr:YSGG laser increased the shear bond strength of GIC to composite resin; however, in RMGIC only laser etching resulted in significantly higher bond strength. These findings were supported by SEM results. The fracture mode was evaluated under a stereomicroscope at ×20.

Does 8-methacryloxyoctyl trimethoxy silane (8-MOTS) improve initial bond strength on lithium disilicate glass ceramic?

PubMed

Maruo, Yukinori; Nishigawa, Goro; Yoshihara, Kumiko; Minagi, Shogo; Matsumoto, Takuya; Irie, Masao

2017-03-01

Dental ceramic surfaces are modified with silane coupling agents, such as γ-methacryloxypropyl trimethoxy silane (γ-MPTS), to improve bond strength. For bonding between lithium disilicate glass ceramic and resin cement, the objective was to investigate if 8-methacryloxyoctyl trimethoxy silane (8-MOTS) could yield a similar performance as the widely used γ-MPTS. One hundred and ten lithium disilicate glass ceramic specimens were randomly divided into 11 groups (n=10) according to pretreatment regime. All specimens were pretreated with a different solution composed of one or a combination of these agents: 10 or 20wt% silane coupling agent of γ-MPTS or 8-MOTS, followed by a hydrolysis solution of acetic acid or 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP). Each pretreated surface was luted to a stainless steel rod of 3.6mm diameter and 2.0mm height with resin cement. Shear bond strength between ceramic and cement was measured after 24-h storage in 37°C distilled water. 8-MOTS produced the same bonding performance as γ-MPTS. Both silane coupling agents significantly increased the bond strength of resin cement, depending on their concentration. When activated by 10-MDP hydrolysis solution, 20wt% concentration produced the highest values (γ-MPTS: 24.9±5.1MPa; 8-MOTS: 24.6±7.4MPa). Hydrolysis with acetic acid produced lower bond strengths than with 10-MDP. Silane coupling pretreatment with 8-MOTS increased the initial bond strength between lithium disilicate glass ceramic and resin cement, rendering the same bonding effect as the conventional γ-MPTS. Copyright © 2016 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

A Comparison between Shear Bond Strength of VMK Master Porcelain with Three Base-metal Alloys (Ni-cr-T3, VeraBond, Super Cast) and One Noble Alloy (X-33) in Metal-ceramic Restorations

PubMed Central

Ahmadzadeh, A; Neshati, A; Mousavi, N; Epakchi, S; Dabaghi Tabriz, F; Sarbazi, AH

2013-01-01

Statement of Problem: The increase in the use of metal-ceramic restorations and a high prevalence of porcelain chipping entails introducing an alloy which is more compatible with porcelain and causes a stronger bond between the two. This study is to compare shear bond strength of three base-metal alloys and one noble alloy with the commonly used VMK Master Porcelain. Materials and Method: Three different groups of base-metal alloys (Ni-cr-T3, Super Cast, and VeraBond) and one group of noble alloy (X-33) were selected. Each group consisted of 15 alloy samples. All groups went through the casting process and change from wax pattern into metal disks. The VMK Master Porcelain was then fired on each group. All the specimens were put in the UTM; a shear force was loaded until a fracture occurred and the fracture force was consequently recorded. The data were analyzed by SPSS Version 16 and One-Way ANOVA was run to compare the shear strength between the groups. Furthermore, the groups were compared two-by-two by adopting Tukey test. Results: The findings of this study revealed shear bond strength of Ni-Cr-T3 alloy was higher than the three other alloys (94 MPa or 330 N). Super Cast alloy had the second greatest shear bond strength (80. 87Mpa or 283.87 N). Both VeraBond (69.66 MPa or 245 N) and x-33 alloys (66.53 MPa or 234 N) took the third place. Conclusion: Ni-Cr-T3 with VMK Master Porcelain has the greatest shear bond strength. Therefore, employment of this low-cost alloy is recommended in metal-ceramic restorations. PMID:24724144

Effect of Bioactive Glass air Abrasion on Shear Bond Strength of Two Adhesive Resins to Decalcified Enamel

PubMed Central

Eshghi, Alireza; Khoroushi, Maryam; Rezvani, Alireza

2014-01-01

Objective: Bioactive glass air abrasion is a conservative technique to remove initial decalcified tissue and caries. This study examined the shear bond strength of composite resin to sound and decalcified enamel air-abraded by bioactive glass (BAG) or alumina using etch-and-rinse and self-etch adhesives. Materials and Methods: Forty-eight permanent molars were root-amputated and sectioned mesiodistally. The obtained 96 specimens were mounted in acrylic resin; the buccal and lingual surfaces remained exposed. A demineralizing solution was used to decalcify half the specimens. Both sound and decalcified specimens were divided into two groups of alumina and bioactive glass air abrasion. In each group, the specimens were subdivided into two subgroups of Clearfil SE Bond or OptiBond FL adhesives (n=12). Composite resin cylinders were bonded on enamel surfaces cured and underwent thermocycling. The specimens were tested for shear bond strength. Data were analyzed using SPSS 16.0 and three-way ANOVA (α=0.05). Similar to the experimental groups, the enamel surface of one specimen underwent SEM evaluation. Results: No significant differences were observed in composite resin bond strength subsequent to alumina or bioactive glass air abrasion preparation techniques (P=0.987). There were no statistically significant differences between the bond strength of etch-and-rinse and self-etch adhesive groups (P=1). Also, decalcified or intact enamel groups had no significant difference (P=0.918). However, SEM analysis showed much less enamel irregularities with BAG air abrasion compared to alumina air abrasion. Conclusion: Under the limitations of this study, preparation of both intact and decalcified enamel surfaces with bioactive glass air abrasion results in similar bond strength of composite resin in comparison with alumina air abrasion using etch-&-rinse or self-etch adhesives. PMID:25628694

Microtensile bond strength analysis of different adhesive systems and dentin prepared with high-speed and Er:YAG laser: a comparative study.

PubMed

Oliveira, Denise Cerqueira; Manhães, Lussara Azevedo; Marques, Márcia Martins; Matos, Adriana Bona

2005-04-01

The aim of this study was to evaluate the bond strength of two adhesive systems (Single Bond and Clearfil SE Bond) subjected or not to a thermocycling procedure and applied to cavities prepared either with high-speed diamond bur or Er:YAG laser. One of the possible applications of dental lasers includes increasing the quality of bond strength. This in vitro study was carried out using a microtensile test on 16 bovine teeth, divided into eight groups. Cavities were prepared on superficial dentin of the medium portion of the buccal surface. After application of adhesive systems, composite restorations were performed at 5-mm height. After 24 h, four groups of teeth were immersed in water, and the other four were thermocycled. Bonded specimens were sectioned into serial 1x1-mm beams, which were subjected to a microtensile test. Final values of bond strength were measured, expressed in MPa, and statistically analyzed. Results were as follows: G1 (26.281 +/- 5.454 MPa); G2 (10.965 +/- 3.714 MPa); G3 (18.549 +/- 6.113 MPa); G4 (14.295 +/- 3.806 MPa); G5 (18.225 +/- 5.701 MPa); G6 (5.588 +/- 2.211 MPa); G7 (18.256 +/- 3.819 MPa); and G8 (15.423 +/- 4.714 MPa). Self-etching adhesive system (SE) produced more stable bond strength results than the system that indicates total etching (SB). For dentin prepared at high speed, the total etching adhesive system was more indicated, whereas Er:YAG laser-preparation dentin was not influenced by the adhesive system. The thermocycling procedure could negatively affect microtensile bond strength of both adhesive systems, being more deleterious to SB than to SE.

Influence of irradiation by a novel CO2 9.3-μm short-pulsed laser on sealant bond strength.

PubMed

Rechmann, P; Sherathiya, K; Kinsel, R; Vaderhobli, R; Rechmann, B M T

2017-04-01

The objective of this in vitro study was to evaluate whether irradiation of enamel with a novel CO 2 9.3-μm short-pulsed laser using energies that enhance caries resistance influences the shear bond strength of composite resin sealants to the irradiated enamel. Seventy bovine and 240 human enamel samples were irradiated with a 9.3-μm carbon dioxide laser (Solea, Convergent Dental, Inc., Natick, MA) with four different laser energies known to enhance caries resistance or ablate enamel (pulse duration from 3 μs at 1.6 mJ/pulse to 43 μs at 14.9 mJ/pulse with fluences between 3.3 and 30.4 J/cm 2 , pulse repetition rate between 4.1 and 41.3 Hz, beam diameter of 0.25 mm and 1-mm spiral pattern, and focus distance of 4-15 mm). Irradiation was performed "freehand" or using a computerized, motor-driven stage. Enamel etching was achieved with 37% phosphoric acid (Scotchbond Universal etchant, 3M ESPE, St. Paul, MN). As bonding agent, Adper Single Bond Plus was used followed by placing Z250 Filtek Supreme flowable composite resin (both 3M ESPE). After 24 h water storage, a single-plane shear bond test was performed (UltraTester, Ultradent Products, Inc., South Jordan, UT). All laser-irradiated samples showed equal or higher bond strength than non-laser-treated controls. The highest shear bond strength values were observed with the 3-μs pulse duration/0.25-mm laser pattern (mean ± SD = 31.90 ± 2.50 MPa), representing a significant 27.4% bond strength increase over the controls (25.04 ± 2.80 MPa, P ≤ 0.0001). Two other caries-preventive irradiation (3 μs/1 mm and 7 μs/0.25 mm) and one ablative pattern (23 μs/0.25 mm) achieved significantly increased bond strength compared to the controls. Bovine enamel also showed in all test groups increased shear bond strength over the controls. Computerized motor-driven stage irradiation did not show superior bond strength values over the clinically more relevant freehand irradiation. Enamel that is made caries-resistant with CO 2 9.3-μm short-pulsed laser irradiation showed at least equal or significantly higher shear bond strength to pit and fissure sealants than non-laser-irradiated enamel. The risk of a sealant failure due to CO 2 9.3-μm short-pulsed laser irradiation appears reduced. If additional laser ablation is required before placing a sealant, the CO 2 9.3-μm enamel laser-cut showed equivalent or superior bond strength to a flowable sealant.

NASA Astrophysics Data System (ADS)

Yao, Jinhuan; Li, Yanwei; Li, Xuanhai; Le, Shiru

2014-07-01

The geometric structure, electronic structure, and stability of In-substituted ZnFe2O4 (Zn7InFe16O32 and Zn8Fe15InO32) are investigated by the density functional theory at generalized gradient approximation level. Compared with the perfect ZnFe2O4 (Zn8Fe16O32), the unit cell volume of In-substituted ZnFe2O4 increases and the structure deforms slightly. The formation energy of In substitution for Zn is smaller than that of In substitution for Fe, indicating that Zn7InFe16O32 is easier to be formed than Zn8Fe15InO32. In substitution changes the properties of ZnFe2O4 from semiconducting character to metallic character. For ZnFe2O4 and In-substituted ZnFe2O4, the strength of O-Zn bond is stronger than O-Fe bond and both of them have a covalent bond character. The strength of O-In bond is similar to that of O-Zn bond in Zn7InFe16O32, but weaker than O-Fe in Zn8Fe15InO32. In substitution for Zn causes the strength of O-Fe bonds around In atom to weaken. In substitution for Fe causes the strength of O-Zn bonds around In atom to weaken obviously, while the strength of O-Fe bonds strengthen slightly.

[Effects of magnetron sputtered ZrN on the bonding strength of titanium porcelain].

PubMed

Zhou, Shu; Zhang, Wen-yan; Guang, Han-bing; Xia, Yang; Zhang, Fei-min

2009-04-01

To investigate the effect of magnetron sputtered ZrN on the bonding strength between a low-fusing porcelain (Ti/Vita titankeramik system) and commercially pure cast titanium. Sixteen specimens were randomly assigned to test group and control group (n=8). The control group received no surface treated. Magnetron sputtered ZrN film was deposited on the surface of specimens in the test group. Then the sixteen titanium-porcelain specimens were prepared in a rectangular shape and went through three-point bending test on a universal test machine. The bond strength of Ti/porcelain was recorded. The phase composition of the specimens was analyzed using X-ray diffraction (XRD). The interface at titanium and porcelain and the titanium surface after debonding were observed with a scanning electron microscopy (SEM) and analyzed using energy depressive spectrum (EDS). New phase of ZrN was found with XRD in the test group. Statistical analysis showed higher bond strength following ZrN surface treatment in the test group [(45.991+/-0.648) MPa] than that in the control group [(29.483+/-1.007) MPa] (P=0.000). Bonded ceramic could be observed in test group, the amount of bonded ceramic was more than that in the control group. No obvious bonded ceramic in control group was found. Magnetron sputtered ZrN can improve bond strength of Ti/Vita titankeramik system significantly.

Influence of frequency on shear fatigue strength of resin composite to enamel bonds using self-etch adhesives.

PubMed

Takamizawa, Toshiki; Scheidel, Donal D; Barkmeier, Wayne W; Erickson, Robert L; Tsujimoto, Akimasa; Latta, Mark A; Miyazaki, Masashi

2016-09-01

The purpose of this study was to determine the influence of different frequency rates on of bond durability of self-etch adhesives to enamel using shear fatigue strength (SFS) testing. A two-step self-etch adhesive (OX, OptiBond XTR), and two single step self-etch adhesives (GB, G-ӕnial Bond and SU, Scotchbond Universal) were used in this study. The shear fatigue strength (SFS) to enamel was obtained. A staircase method was used to determine the SFS values with 50,000 cycles or until failure occurred. Fatigue testing was performed at frequencies of 5Hz, 10Hz, and 20Hz. For each test condition, 30 specimens were prepared for the SFS testing. Regardless of the bond strength test method, OX showed significantly higher SFS values than the two single-step self-etch adhesives. For each of the three individual self-etch adhesives, there was no significant difference in SFS depending on the frequency rate, although 20Hz results tended to be higher. Regardless of the self-etch adhesive system, frequencies of 5Hz, 10Hz, and 20Hz produced similar results in fatigue strength of resin composite bonded to enamel using 50,000 cycles or until bond failure. Accelerated fatigue testing provides valuable information regarding the long term durability of resin composite to enamel bonding using self-etch adhesive system. Copyright © 2016 Elsevier Ltd. All rights reserved.

Tensile Bond Strength between Soft Liners and Two Chemically Different Denture Base Materials: Effect of Thermocycling.

PubMed

Tugut, Faik; Coskun, Mehmet Emre; Dogan, Derya Ozdemir; Kirmali, Omer; Akin, Hakan

2016-06-01

The bond strength of soft denture liner to a recently introduced denture base resin after thermocycling has not been compared to traditional denture base materials. The objective of this study was to investigate the effects of thermocycling on the tensile bond strength of soft denture liners to two chemically different denture base resins, polymethyl methacrylate (PMMA) and urethane dimethacrylate (UDMA). A total of 48 PMMA and UDMA tensile test specimens were fabricated by attaching two different soft denture liners (Molloplast-B, Permaflex) according to the manufacturers' instructions and assigned to two groups. Half of the specimens for each group were stored in water for 1 week, and the other half were thermocycled (5000 cycles) between baths of 5°C and 55°C. Specimens were mounted on a universal testing machine with a 5 mm/min crosshead speed. The data were analyzed with three-way ANOVA and post hoc Tukey-Kramer multiple comparisons tests (α = 0.05). The highest bond strength was measured in the specimens from the UDMA/Molloplast groups, and the lowest was seen in the PMMA/Permaflex group. No significant difference in bond strength was detected in PMMA/Permaflex groups after thermocycling (p = 0.082), whereas other groups exhibited significant differences after thermocycling (p < 0.05). Thermocycling decreased the bond strength values in both the PMMA and UDMA groups. Regardless of types of soft liners, PMMA specimens presented lower bond strength values than UDMA specimens, both before and after thermocycling. © 2015 by the American College of Prosthodontists.

A Comparative Evaluation of Effect of Different Chemical Solvents on the Shear Bond Strength of Glass Fiber reinforced Post to Core Material

PubMed Central

Samadi, Firoza; Jaiswal, JN; Saha, Sonali

2014-01-01

ABSTRACT% Aim: To compare the effect of different chemical solvents on glass fiber reinforced posts and to study the effect of these solvents on the shear bond strength of glass fiber reinforced post to core material. Materials and methods: This study was conducted to evaluate the effect of three chemical solvents, i.e. silane coupling agent, 6% H2O2 and 37% phosphoric acid on the shear bond strength of glass fiber post to a composite resin restorative material. The changes in post surface characteristics after different treatments were also observed, using scanning electron microscopy (SEM) and shear bond strength was analyzed using universal testing machine (UTM). Results: Surface treatment with hydrogen peroxide had greatest impact on the post surface followed by 37% phosphoric acid and silane. On evaluation of the shear bond strength, 6% H2O2 exhibited the maximum shear bond strength followed in descending order by 37% phosphoric acid and silane respectively. Conclusion: The surface treatment of glass fiber post enhances the adhesion between the post and composite resin which is used as core material. Failure of a fiber post and composite resin core often occurs at the junction between the two materials. This failure process requires better characterization. How to cite this article: Sharma A, Samadi F, Jaiswal JN, Saha S. A Comparative Evaluation of Effect of Different Chemical Solvents on the Shear Bond Strength of Glass Fiber Reinforced Post to Core Material. Int J Clin Pediatr Dent 2014;7(3):192-196. PMID:25709300

Evaluation of tensile bond strength of heat cure and autopolymerizing silicone-based resilient denture liners before and after thermocycling.

PubMed

Madan, Nishtha; Datta, Kusum

2012-01-01

To assess the effect of simulated mouth conditions reproduced with thermocycling on the tensile bond strength of two silicone based resilient denture liners with acrylic resin bases. Two silicone-based soft denture liners (Mollosil - Chairside autopolymerization and Molloplast B - Heat polymerization) were tested. For each liner, 30 specimens with a cross-sectional area of 10 Χ 10 mm and thickness 3 mm were processed between two acrylic blocks (Trevalon). Specimens were divided into a control group that was stored for 24 hours in water at 37°C and a test group that was thermocycled (2500 cycles) between baths of 5° and 55°C. Tensile bond strength (kg/cm²) was determined in a universal testing machine using crosshead speed of 5 mm/min. The student t-test was used to determine the significance of the difference in bond strength between the two liners. The mean tensile bond strength for control and thermocycled specimens of the two liners were: Mollosil (6.82 kg/cm² and 8.41 kg/cm²) and Molloplast-B (16.30 kg/cm² and 13.67 kg/cm²), respectively. Comparison of bond strength of control specimens with thermocycled specimens of the liners indicated a significant difference for both Mollosil (P=0.045) and Molloplast-B (P=0.027). Comparison between control specimens of both liners and thermocycled specimens of both liners indicated a highly significant difference (P<0.001). Heat polymerized resilient denture liner Molloplast-B had higher tensile bond strength than autopolymerizing liner Mollosil regardless of thermocycling. The bond strength of Mollosil increased after thermocycling while that of Molloplast-B decreased after thermocycling. Although heat-polymerized denture liners require more processing time than autopolymerizing liners, but they display much better adhesion properties to denture base resin and should thus be preferred when soft liner has to be used for a longer duration of time.

Microtensile bond strength of bulk-fill restorative composites to dentin.

PubMed

Mandava, Jyothi; Vegesna, Divya-Prasanna; Ravi, Ravichandra; Boddeda, Mohan-Rao; Uppalapati, Lakshman-Varma; Ghazanfaruddin, M D

2017-08-01

To facilitate the easier placement of direct resin composite in deeper cavities, bulk fill composites have been introduced. The Mechanical stability of fillings in stress bearing areas restored with bulk-fill resin composites is still open to question, since long term clinical studies are not available so far. Thus, the objective of the study was to evaluate and compare the microtensile bond strength of three bulk-fill restorative composites with a nanohybrid composite. Class I cavities were prepared on sixty extracted mandibular molars. Teeth were divided into 4 groups (n= 15 each) and in group I, the prepared cavities were restored with nanohybrid (Filtek Z250 XT) restorative composite in an incremental manner. In group II, III and IV, the bulk-fill composites (Filtek, Tetric EvoCeram, X-tra fil bulk-fill restoratives) were placed as a 4 mm single increment and light cured. The restored teeth were subjected to thermocycling and bond strength testing was done using instron testing machine. The mode of failure was assessed by scanning electron microscope (SEM). The bond strength values obtained in megapascals (MPa) were subjected to statistical analysis, using SPSS/PC version 20 software.One-way ANOVA was used for groupwise comparison of the bond strength. Tukey's Post Hoc test was used for pairwise comparisons among the groups. The highest mean bond strength was achieved with Filtek bulk-fill restorative showing statistically significant difference with Tetric EvoCeram bulk-fill ( p < 0.003) and X-tra fil bulk-fill ( p <0.001) composites. Adhesive failures are mostly observed with X-tra fil bulk fill composites, whereas mixed failures are more common with other bulk fill composites. Bulk-fill composites exhibited adequate bond strength to dentin and can be considered as restorative material of choice in posterior stress bearing areas. Key words: Bond strength, Bulk-fill restoratives, Configuration factor, Polymerization shrinkage.

Effect of chlorhexidine and ethanol on push-out bond strength of fiber posts under cyclic loading.

PubMed

Cecchin, Doglas; Giacomin, Mateus; Farina, Ana Paula; Bhering, Cláudia Lopes; Mesquita, Marcelo Ferraz; Ferraz, Caio Cezar

2014-02-01

To investigate the effects of pretreatment with 2% chlorhexidine in a gel base (CHX) and 100% ethanol (EtOH) on the bond strength between fiber posts relined with resin composite and root dentin under cyclic loading. Forty bovine incisor roots were divided into four groups after phosphoric acid etching: group 1 (control), irrigation with physiological saline solution; group 2, 5 min pretreatment with CHX; group 3, 1 min pretreatment with EtOH; group 4, 5 min pretreatment with CHX followed by 1 min with EtOH. Fiber posts relined with resin composite were cemented with RelyX ARC and the etch-and-rinse adhesive system Scotchbond Multi-Purpose. Each group was randomly divided into two subgroups: 24 h of storage (immediate groups) and cyclic loading (loading groups) with 250,000 cycles in a controlled chewing simulator. All roots were sectioned transversely and push-out tests were performed. Failure modes were observed and the bond strength means were analyzed using ANOVA and Tukey's test (a = 0.05). The mean values for the bond strength test (MPa) in immediate groups were: group 1, 5.44 ± 1.48; group 2, 5.57 ± 1.41; group 3, 5.49 ± 1.48; group 4, 5.57 ± 1.42. Immediate groups showed similar bond strength values (p > 0.05). In the cyclic loading groups, the bond strength values were: group 1, 2.80 ± 0.79; group 2, 4.02 (1.30); group 3, 4.50 ± 1.67; group 4, 4.97 ± 2.00. After cyclic loading, a significant decrease in the control group was observed (p < 0.05), while CHX pretreatment resulted in intermediate values (p < 0.05) and EtOH alone or associated with CHX preserved the bond strength values (p > 0.05). Chlorhexidine and/or ethanol pretreatment preserved the bond strength of the fiber post after cyclic loading.

Rapid adhesive bonding of advanced composites and titanium

NASA Technical Reports Server (NTRS)

Stein, B. A.; Tyeryart, J. R.; Hodgest, W. T.

1985-01-01

Rapid adhesive bonding (RAB) concepts utilize a toroid induction technique to heat the adhesive bond line directly. This technique was used to bond titanium overlap shear specimens with 3 advanced thermoplastic adhesives and APC-2 (graphite/PEEK) composites with PEEK film. Bond strengths equivalent to standard heated-platen press bonds were produced with large reductions in process time. RAB produced very strong bonds in APC-2 adherend specimens; the APC-2 adherends were highly resistant to delamination. Thermal cycling did not significantly affect the shear strengths of RAB titanium bonds with polyimide adhesives. A simple ultrasonic non-destructive evaluation process was found promising for evaluating bond quality.

Shear bond strength of one-step self-etch adhesives to dentin: Evaluation of NaOCl pretreatment.

PubMed

Colombo, Marco; Beltrami, Riccardo; Chiesa, Marco; Poggio, Claudio; Scribante, Andrea

2018-02-01

The aim of this study was to evaluate the influence of dentin pretreatment with NaOCl on shear bond strength of four one-step self-etch adhesives with different pH values. Bovine permanent incisors were used. Four one-step self-etch adhesives were tested: Adper™ Easy Bond, Futurabond NR, G-aenial Bond, Clearfil S3 Bond. One two-step self-etch adhesive (Clearfil SE Bond) was used as control. Group 1- no pretreatment; group 2- pretratment with 5,25 % NaOCl; group 3- pretreatment with 37 % H3PO4 etching and 5,25 % NaOCl. A hybrid composite resin was inserted into the dentin surface. The specimens were tested in a universal testing machine. The examiners evaluated the fractured surfaces in optical microscope to determine failure modes, quantified with adhesive remnant index (ARI). Dentin pretreatment variably influenced bond strength values of the different adhesive systems. When no dentin pretreatment was applied, no significant differences were found ( P >.05) among four adhesives tested. No significant differences were recorded when comparing NaOCl pretreatment with H3PO4 + NaOCl pretreatment for all adhesive tested ( P >.05) except Clearfil S3 Bond that showed higher shear bond strength values when H3PO4 was applied. Frequencies of ARI scores were calculated. The influence of dentin pretreatment with NaOCl depends on the composition of each adhesive system used. There was no difference in bond strength values among self-etch adhesives with different pH values. Key words: Dentin, pretreatment, self-etch adhesives.

Influence of Bond Coat on HVOF-Sprayed Gradient Cermet Coating on Copper Alloy

NASA Astrophysics Data System (ADS)

Ke, Peng; Cai, Fei; Chen, Wanglin; Wang, Shuoyu; Ni, Zhenhang; Hu, Xiaohong; Li, Mingxi; Zhu, Guanghong; Zhang, Shihong

2017-06-01

Coatings are required on mold copper plates to prolong their service life through enhanced hardness, wear resistance, and oxidation resistance. In the present study, NiCr-30 wt.%Cr3C2 ceramic-metallic (cermet) layers were deposited by high velocity oxy-fuel (HVOF) spraying on different designed bond layers, including electroplated Ni, HVOF-sprayed NiCr, and double-decker Ni-NiCr. Annealing was also conducted on the gradient coating (GC) with NiCr bond layer to improve the wear resistance and adhesion strength. Coating microstructure was investigated by scanning electron microscopy and x-ray diffraction analysis. Mechanical properties including microhardness, wear resistance, and adhesion strength of the different coatings were evaluated systematically. The results show that the types of metallic bond layer and annealing process had a significant impact on the mechanical properties of the GCs. The GCs with electroplated Ni bond layer exhibited the highest adhesion strength (about 70 MPa). However, the GC with HVOF-sprayed NiCr bond layer exhibited better wear resistance. The wear resistance and adhesion strength of the coating with NiCr metallic bond layer were enhanced after annealing.

Valence-bond theory of compounds of transition metals

PubMed Central

Pauling, Linus

1975-01-01

An equation relating the strength (bondforming power) of an spd hybrid bond orbital to the angles it makes with other bond orbitals is formulated and applied in the discussion of the structures of transition-metal carbonyls and other substances by the valence-bond method. The rather simple theory gives results that agree well with those obtained by the complicated and laborious calculation of sets of orthogonal hybrid bond orbitals with maximum strength. PMID:16592279

Resin–dentin bonds to EDTA-treated vs. acid-etched dentin using ethanol wet-bonding

PubMed Central

Sauro, Salvatore; Toledano, Manuel; Aguilera, Fatima Sánchez; Mannocci, Francesco; Pashley, David H.; Tay, Franklin R.; Watson, Timothy F.; Osorio, Raquel

2013-01-01

Objective To compare resin–dentin bond strengths and the micropermeability of hydrophobic vs. hydrophilic resins bonded to acid-etched or EDTA-treated dentin, using the ethanol wet-bonding technique. Methods Flat dentin surfaces from extracted human third molars were conditioned before bonding with: 37% H3PO4 (15 s) or 0.1 M EDTA (60 s). Five experimental resin blends of different hydrophilicities and one commercial adhesive (SBMP: Scotchbond Multi-Purpose) were applied to ethanol wet-dentin (1 min) and light-cured (20 s). The solvated resins were used as primers (50% ethanol/50% comonomers) and their respective neat resins were used as the adhesive. The resin-bonded teeth were stored in distilled water (24 h) and sectioned in beams for microtensile bond strength testing. Modes of failure were examined by stereoscopic light microscopy and SEM. Confocal tandem scanning microscopy (TSM) interfacial characterization and micropermeability were also performed after filling the pulp chamber with 1 wt% aqueous rhodamine-B. Results The most hydrophobic resin 1 gave the lowest bond strength values to acid-etched dentin and all beams failed prematurely when the resin was applied to EDTA-treated dentin. Resins 2 and 3 gave intermediate bond strengths to both conditioned substrates. Resin 4, an acidic hydrophilic resin, gave the highest bond strengths to both EDTA-treated and acid-etched dentin. Resin 5 was the only hydrophilic resin showing poor resin infiltration when applied on acid-etched dentin. Significance The ethanol wet-bonding technique may improve the infiltration of most of the adhesives used in this study into dentin, especially when applied to EDTA-treated dentin. The chemical composition of the resin blends was a determining factor influencing the ability of adhesives to bond to EDTA-treated or 37% H3PO4 acid-etched dentin, when using the ethanol wet-bonding technique in a clinically relevant time period. PMID:20074787

Sealing ability and bond strength of four contemporary adhesives to enamel and to dentine.

PubMed

Atash, R; Vanden Abbeele, A

2005-12-01

To compare the shear bond strength and microleakage of four adhesive systems to the enamel and dentine of primary bovine teeth. 120 bovine primary mandibular incisors were collected and stored in an aqueous 1% chloramine solution at room temperature for no longer than 3 months after extraction (80 for shear bond testing and 40 for microleakage evaluation). The adhesives tested were Clearfil SE bond (SE), Adper Prompt L Pop (LP), Xeno III (XE), and Prime and Bond NT (PB). For shear bond strength testing the specimens were wet ground to 600 grit SiC paper to expose a flat enamel or dentine surface. After bonding and restoration with Dyract AP (DAP), the teeth were subjected to shear stress using a universal testing machine. For microleakage evaluation, facial class V cavities were prepared half in enamel and half in cementum. All cavities were restored with DAP. After thermocycling and immersion in 2% methylene blue, the dye penetration was evaluated under a stereomicroscope. All data were analysed by Chi-square tests or Fisher's tests when adapted in order to determine the significant differences between groups. Results were considered as significant for p < 0.05. Results were analysed with an ANOVA test and a Bonferroni's multiple comparison. The level of significance was p < 0.05. Shear bond strength values (MPa,) ranged from: on enamel 11.06 to 5.34, in decreasing order SE, LP, XE and PB and on dentine 10.47 to 4.74, in decreasing order SE, XE, LP and PB. Differences in bond strengths between the four systems on enamel and dentine were all statistically significant, excepted for XE vs LP (shear bond at dentine). No significant differences were recorded in the microleakage degree between the four adhesive systems on enamel and on dentine (p > 0.0.5). The highest shear bond strength was achieved by Clearfil SE bond and the lowest by Prime and Bond NT. There was no significant difference concerning the sealing ability of the four adhesive systems.

The effect of storage conditions, contamination modes and cleaning procedures on the resin bond strength to lithium disilicate ceramic.

PubMed

Klosa, Karsten; Wolfart, Stefan; Lehmann, Frank; Wenz, Hans-Jürgen; Kern, Matthias

2009-04-01

The purpose of this in-vitro study was to evaluate the resin bond strength to pre-etched lithium disilicate ceramic using different cleaning methods after two contamination modes (saliva or saliva and silicone). Plexiglas tubes filled with composite resin (MultiCore Flow) were bonded to etched and silanized ceramic disks made of lithium disilicate ceramic (IPS e.max Press) using a luting resin (Multilink Automix). Either etched or unetched ceramic surfaces were contaminated with saliva or with saliva followed by a disclosing silicone. Groups of 16 specimens each were bonded after pretreatment using 4 surface cleaning agents (37% phosphoric acid, 5% hydrofluoric acid, 96% isopropanol, air polishing device with sodium bicarbonate) in different combinations. Before measuring tensile bond strength, specimens were stored for 3 or 150 days with thermocycling. After 150 days of storage, etching of saliva-contaminated surfaces with 5% hydrofluoric acid and/or 37% phosphoric acid provided statistically significantly higher bond strengths (37.9 to 49.5 MPa) than the other cleaning methods (1.7 to 15.5 MPa). After saliva and silicone contamination, etching with 5% hydrofluoric acid provided statistically significantly higher bond strengths (44.5 to 50.3 MPa) than all other cleaning methods (0.3 to 13.5 MPa). Ceramic cleaning methods after try-in procedures have a significant influence on the resin bond strength and are dependent on the type of contamination. Re-etching lithium disilicate ceramic with 5% hydrofluoric acid is most effective in removing contamination with saliva and/or a silicone disclosing medium.

Effect of different surface treatments on tensile bond strength of silicone-based soft denture liner.

PubMed

Akin, Hakan; Tugut, Faik; Mutaf, Burcu; Akin, Gulsah; Ozdemir, A Kemal

2011-11-01

Failure of the bond between the acrylic resin and resilient liner material is commonly encountered in clinical practice. The purpose of this study was to investigate the effect of different surface treatments (sandblasting, Er:YAG, Nd:YAG, and KTP lasers) on tensile bond strength of silicone-based soft denture liner. Polymethyl methacrylate test specimens were fabricated and each received one of eight surface treatments: untreated (control), sandblasted, Er:YAG laser irradiated, sandblasted + Er:YAG laser irradiated, Nd:YAG laser irradiated, sandblasted + Nd:YAG laser irradiated, KTP laser irradiated, and sandblasted + KTP laser irradiated. The resilient liner specimens (n = 15) were processed between two polymethyl methacrylate (PMMA) blocks. Bonding strength of the liners to PMMA were compared by tensile test with the use of a universal testing machine at a crosshead speed of 5 mm/min. Kruskal-Wallis and Wilcoxon tests were used to analyze the data (α = 0.05). Altering the polymethyl methacrylate surface by Er:YAG laser significantly increased the bond strengths in polymethyl methacrylate/silicone specimens, however, sandblasting before applying a lining material had a weakening effect on the bond. In addition, Nd:YAG and KTP lasers were found to be ineffective for increasing the strength of the bond.

Effect of delayed polymerization time and bracket manipulation on orthodontic bracket bonding

NASA Astrophysics Data System (ADS)

Ponikvar, Michael J.

This study examined the effect of bracket manipulation in combination with delayed polymerization times on orthodontic bracket shear bond strength and degree of resin composite conversion. Orthodontics brackets were bonded to extracted third molars in a simulated oral environment after a set period of delayed polymerization time and bracket manipulation. After curing the bracket adhesive, each bracket underwent shear bond strength testing followed by micro-Raman spectroscopy analysis to measure the degree of conversion of the resin composite. Results demonstrated the shear bond strength and the degree of conversion of ceramic brackets did not vary over time. However, with stainless steel brackets there was a significant effect (p ≤ 0.05) of delay time on shear bond strength between the 0.5 min and 10 min bracket groups. In addition, stainless steel brackets showed significant differences related to degree of conversion over time between the 0.5 min and 5 min groups, in addition to the 0.5 min and 10 min groups. This investigation suggests that delaying bracket adhesive polymerization up to a period of 10 min then adjusting the orthodontic bracket may increase both shear bond strength and degree of conversion of stainless steel brackets while having no effect on ceramic brackets.

Surface fluorination of zirconia: adhesive bond strength comparison to commercial primers.

PubMed

Piascik, Jeffrey R; Swift, Edward J; Braswell, Krista; Stoner, Brian R

2012-06-01

This study evaluated contact angle and shear bond strength of three commercial zirconia primers and compared them to a recently developed fluorination pre-treatment. Earlier investigations reported that plasma fluorinated zirconia modifies the chemical bonding structure creating a more reactive surface. Yttria-stabilized zirconia (LAVA, 3M ESPE) plates were highly polished using 3μm diamond paste (R(a) ∼200nm) prior to pretreatments. After primer and fluorination treatment, contact angles were measured to quantify surface hydrophobicity before and after ethanol clean. Additionally, simple shear bond tests were performed to measure the adhesion strength to a composite resin. Plasma fluorination produced the lowest contact angle (7.8°) and the highest shear bond strength (37.3MPa) suggesting this pretreatment facilitates a more "chemically" active surface for adhesive bonding. It is hypothesized that plasma fluorination increase hydroxylation at the surface, making it more reactive, thus allowing for covalent bonding between zirconia surface and resin cement. A strong correlation was observed between contact angle and adhesion strength for all specimens; a relationship which may help understand the frequency and modes of failures, clinically. It is also believed that this surface treatment can increase long-term viability of zirconia restorations over other adhesive techniques. Copyright © 2012 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Influence of the processing route of porcelain/Ti-6Al-4V interfaces on shear bond strength.

PubMed

Toptan, Fatih; Alves, Alexandra C; Henriques, Bruno; Souza, Júlio C M; Coelho, Rui; Silva, Filipe S; Rocha, Luís A; Ariza, Edith

2013-04-01

This study aims at evaluating the two-fold effect of initial surface conditions and dental porcelain-to-Ti-6Al-4V alloy joining processing route on the shear bond strength. Porcelain-to-Ti-6Al-4V samples were processed by conventional furnace firing (porcelain-fused-to-metal) and hot pressing. Prior to the processing, Ti-6Al-4V cylinders were prepared by three different surface treatments: polishing, alumina or silica blasting. Within the firing process, polished and alumina blasted samples were subjected to two different cooling rates: air cooling and a slower cooling rate (65°C/min). Metal/porcelain bond strength was evaluated by shear bond test. The data were analyzed using one-way ANOVA followed by Tuckey's test (p<0.05). Before and after shear bond tests, metallic surfaces and metal/ceramic interfaces were examined by Field Emission Gun Scanning Electron Microscope (FEG-SEM) equipped with Energy Dispersive X-Ray Spectroscopy (EDS). Shear bond strength values of the porcelain-to-Ti-6Al-4V alloy interfaces ranged from 27.1±8.9MPa for porcelain fused to polished samples up to 134.0±43.4MPa for porcelain fused to alumina blasted samples. According to the statistical analysis, no significant difference were found on the shear bond strength values for different cooling rates. Processing method was statistically significant only for the polished samples, and airborne particle abrasion was statistically significant only for the fired samples. The type of the blasting material did not cause a statistically significant difference on the shear bond strength values. Shear bond strength of dental porcelain to Ti-6Al-4V alloys can be significantly improved from controlled conditions of surface treatments and processing methods. Copyright © 2013 Elsevier Ltd. All rights reserved.

Shear bond strength of veneering porcelain to zirconia: Effect of surface treatment by CNC-milling and composite layer deposition on zirconia.

PubMed

Santos, R L P; Silva, F S; Nascimento, R M; Souza, J C M; Motta, F V; Carvalho, O; Henriques, B

2016-07-01

The purpose of this study was to evaluate the shear bond strength of veneering feldspathic porcelain to zirconia substrates modified by CNC-milling process or by coating zirconia with a composite interlayer. Four types of zirconia-porcelain interface configurations were tested: RZ - porcelain bonded to rough zirconia substrate (n=16); PZ - porcelain bonded to zirconia substrate with surface holes (n=16); RZI - application of a composite interlayer between the veneering porcelain and the rough zirconia substrate (n=16); PZI - application of a composite interlayer between the porcelain and the zirconia substrate treated by CNC-milling (n=16). The composite interlayer was composed of zirconia particles reinforced porcelain (30%, vol%). The mechanical properties of the ceramic composite have been determined. The shear bond strength test was performed at 0.5mm/min using a universal testing machine. The interfaces of fractured and untested specimens were examined by FEG-SEM/EDS. Data was analyzed with Shapiro-Wilk test to test the assumption of normality. The one-way ANOVA followed by Tukey HSD multiple comparison test was used to compare shear bond strength results (α=0.05). The shear bond strength of PZ (100±15MPa) and RZI (96±11MPa) specimens were higher than that recorded for RZ (control group) specimens (89±15MPa), although not significantly (p>0.05). The highest shear bond strength values were recorded for PZI specimens (138±19MPa), yielding a significant improvement of 55% relative to RZ specimens (p<0.05). This study shows that it is possible to highly enhance the zirconia-porcelain bond strength - even by ~55% - by combining surface holes in zirconia frameworks and the application of a proper ceramic composite interlayer. Copyright © 2016 Elsevier Ltd. All rights reserved.

In vitro Assessment of Influence of Various Bleaching Protocols on the Strength of Ceramic Orthodontic Brackets bonded to Bleached Tooth Surface: A Comparative Study.

PubMed

Iska, Divya; Devanna, Raghu; Singh, Madhvi; Chitumalla, Rajkiran; Balasubramanian, Sai C Bala; Goutam, Manish

2017-12-01

Esthetics is one of the common issues because of which patients consult dental orthodontic treatment. Two ways of tooth bleaching are available these days, which includes in-office bleach and home bleach. Various bleaching protocols are available these days for treating the tooth surfaces. Hence, we planned the present study for investigating the impact of various intracoronal bleaching protocols on shear bond strength of ceramic brackets bonded to tooth surface after bleaching. The present study included assessment of 100 extracted maxillary central incisors with the integrated buccal surface. A resin block was made and individual teeth were embedded in each block. Root canal therapy procedure was performed in all the teeth, after which 2 mm short of tooth apex up to the level of cementoenamel junction, removal of the root canal filling was done. All the samples were broadly divided into four study groups with 25 samples in each group. Bleaching procedure was carried in all the samples intracoronally followed by testing of shear bond strength using universal force testing machine. Following the modified adhesive remnant index (AI), assessment of remaining adhesive on the brackets was done. All the results were compiled and analyzed by Statistical Package for the Social Sciences (SPSS) software version 17.0. In the control group, mean shear bond strength was found to be 17.9 MPa. While comparing the carbamide peroxide (CP) group with sodium perborate study group, we observed a statistically significant difference. Nonsignificant results were obtained while comparing the shear bond strength in between sodium perborate group and hydrogen peroxide (HP) group. Intracoronal bleaching does affect the shear bond strength of ceramic brackets. Sodium perborate bleaching influences shear bond strength more strongly than other bleaching agents such as CP and HP. In patients undergoing orthodontic treatment, HP is a preferred agent where bleaching has to be followed by orthodontic bonding to the tooth surface.

Influence of dimethyl sulfoxide used as a solvent on the physical properties and long-term dentin bonding of hydrophilic resins.

PubMed

Stape, Thiago Henrique Scarabello; Tezvergil-Mutluay, Arzu; Mutluay, Mustafa Murat; Martins, Luís Roberto Marcondes; do Prado, Rosana Leal; Pizi, Eliane Cristina Gava; Tjäderhane, Leo

2016-12-01

To examine the feasibility of dimethyl sulfoxide (DMSO) incorporation into relatively hydrophilic resins as a new potential method to improve the durability of resin-dentin bonds. Six experimental light-curing BisGMA/HEMA resins solvated in ethanol and DMSO with increasing concentrations of DMSO (0, 0.5, 1, 2, 4 and 10wt%) were prepared. The degree of conversion (DC) was evaluated by Fourier Transform Infrared Spectroscopy (n=8); water sorption (Wsp) and water solubility (Wso) were gravimetrically assessed (n=10); and flexural strength (FS) and elastic modulus (E) were determined by a three-point bending flexural test (n=10). Flat dentin surfaces on sound third molars (n=10/group) were bonded with resins containing 0, 2, 4 and 10wt% DMSO used as a two-step etch-and-rinse system. Dentin microtensile bond strength was determined at 24h and after two-year aging in artificial saliva at 37°C. DMSO significantly affected Wsp (p=0.0006), DC, Wso, FS, and E (p<0.0001). In general, the resins' mechanical/physical properties were not affected by 2% or lower DMSO incorporation. Incorporation of 4% or higher DMSO content significantly increased DC, Wsp and Wso, but 2% or higher DMSO concentrations significantly reduced FS and E. No influence on immediate dentin bond strength occurred up to 4% DMSO incorporation. While 4% or higher DMSO concentrations impaired bond strength over time, the resin containing 2% DMSO presented significant higher dentin bond strength compared to the control resin after two year-aging. The use of DMSO as a new solvent in adhesive dentistry improves dentin bonding of relatively hydrophilic resins over time. 2% DMSO incorporation in BisGMA/HEMA resins should be sufficient to reduce bond strength loss without compromising polymer mechanical strength and physical properties. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of air abrasion with alumina or glass beads on surface characteristics of CAD/CAM composite materials and the bond strength of resin cements

PubMed Central

Nobuaki, ARAO; Keiichi, YOSHIDA; Takashi, SAWASE

2015-01-01

ABSTRACT Objective The study aimed to evaluate effects of air abrasion with alumina or glass beads on bond strengths of resin cements to CAD/CAM composite materials. Material and Methods CAD/CAM composite block materials [Cerasmart (CS) and Block HC (BHC)] were pretreated as follows: (a) no treatment (None), (b) application of a ceramic primer (CP), (c) alumina-blasting at 0.2 MPa (AB), (d) AB followed by CP (AB+CP), and (e) glass-beads blasting at 0.4 MPa (GBB) followed by CP (GBB+CP). The composite specimens were bonded to resin composite disks using resin cements [G-CEM Cerasmart (GCCS) and ResiCem (RC)]. The bond strengths after 24 h (TC 0) and after thermal cycling (TC 10,000 at 4–60°C) were measured by shear tests. Three-way ANOVA and the Tukey compromise post hoc tests were used to analyze statistically significant differences between groups (α=0.05). Results For both CAD/CAM composite materials, the None group exhibited a significant decrease in bond strength after TC 10,000 (p<0.05). AB showed significantly higher bond strength after TC 10,000 than the None group, while CP did not (p<0.05). GBB exhibited smaller surface defects than did AB; however, their surface roughnesses were not significantly different (p>0.05). The AB+CP group showed a significantly higher bond strength after TC 10,000 than did the AB group for RC (p<0.05), but not for GCCS. The GBB+CP group showed the highest bond strength for both thermal cyclings (p<0.05). Conclusions Air abrasion with glass beads was more effective in increasing bond durability between the resin cements and CAD/CAM composite materials than was using an alumina powder and a CP. PMID:26814465

Effect of an internal coating technique on tensile bond strengths of resin cements to zirconia ceramics.

PubMed

Kitayama, Shuzo; Nikaido, Toru; Maruoka, Rena; Zhu, Lei; Ikeda, Masaomi; Watanabe, Akihiko; Foxton, Richard M; Miura, Hiroyuki; Tagami, Junji

2009-07-01

This study was conducted to enhance the tensile bond strengths of resin cements to zirconia ceramics. Fifty-six zirconia ceramic specimens (Cercon Base) and twenty-eight silica-based ceramic specimens (GN-1, GN-1 Ceramic Block) were air-abraded using alumina. Thereafter, the zirconia ceramic specimens were divided into two subgroups of 28 each according to the surface pretreatment; no pretreatment (Zr); and the internal coating technique (INT). For INT, the surface of zirconia was coated by fusing silica-based ceramics (Cercon Ceram Kiss). Ceramic surfaces were conditioned with/without a silane coupling agent followed by bonding with one of two resin cements; Panavia F 2.0 (PF) and Superbond C&B (SB). After 24 hours storage in water, the tensile bond strengths were tested (n=7). For both PF and SB, silanization significantly improved the bond strength to GN-1 and INT (p<0.05). The INT coating followed by silanizaton demonstrated enhancement of bonding to zirconia ceramics.

Long-term bonding effectiveness of simplified etch-and-rinse adhesives to dentin after different surface pre-treatments

PubMed Central

Verma, Radhika; Singh, Udai Pratap; Tyagi, Shashi Prabha; Nagpal, Rajni; Manuja, Naveen

2013-01-01

Objective: To evaluate the effect of 2% chlorhexidine (CHX) and 30% proanthocyanidin (PA) application on the immediate and long-term bond strength of simplified etch-and-rinse adhesives to dentin. Materials and Methods: One hundred twenty extracted human molar teeth were ground to expose the flat dentin surface. The teeth were equally divided into six groups according to the adhesives used, either Tetric N Bond or Solobond M and pretreatments given either none, CHX, or PA. Composite cylinder was bonded to each specimen using the respective adhesive technique. Half the samples from each group (n = 10) were then tested immediately. The remaining samples were tested after 6 month storage in distilled water. Results: The mean bond strength of samples was not significantly different upon immediate testing being in the range of 8.4(±0.7) MPa. The bond strength fell dramatically in the control specimens after 6 month storage to around 4.7(±0.33) MPa, while the bond strength was maintained in the samples treated with both CHX and PA. Conclusion: Thirty percent PA was comparable to 2% CHX with respect to preservation of the resin dentin bond over 6 months. PMID:23956543

[Bonding agent influence on shear bond strength of titanium/polyglass interface].

PubMed

Oyafuso, Denise Kanashiro; Bottino, Marco Antonio; Itinoche, Marcos Koiti; Nasraui, Anna Paula; Costa, Elza Maria Valadares da

2003-09-01

There is little information regarding bond strengths of polyglass to metal alloys. This study evaluated the influence of bonding system on shear bond strength of a composite resin (Artglass/Heraeus Kulzer) to cast titanium (Ti). Twenty metallic structures (4mm in diameter, 5mm thick) of titanium grade I were cast shaped and abraded with 250mm aluminum oxide and separated into two groups. For each group was applied one bonding system (Siloc or Retention Flow) before opaque and dentin polymer superposition. This procedure was managed using teflon matrices. They were manipulated and polymerized according to the manufacturer's recommendations. The samples were stored in distilled water for 24 hours at 37º and thermocycled (5º and 55ºC/500 cycles). Shear bond strength tests were performed by using an Instron Universal testing machine at a crosshead speed of 5mm/min. Results were analyzed statistically with one-way ANOVA (a=0,5) and they indicated that the Retention Flow system was statistically better than Siloc (20.74 MPa and 11.65 MPa , respectively). It was possible to conclude that the bonding agent influenced the adhesion between polymer and cast titanium.

Evaluation of Surlyn 8920 as PHE Visor Material and Evaluations of New Adhesives for Improving Bonding Between Teflon and Stainless Steel at Cryogenic Temperature

NASA Technical Reports Server (NTRS)

Ray, Asit K.

1991-01-01

Two studies are presented, and in the first study, Surlyn 8920 (an ionic and amorphous low density polyethylene made by Dupont) was evaluated as a possible replacement of Plexyglass G as PHE visor material. Four formulations of the polymer were made by adding different amounts of UV stabilizer, energy quencher, and antioxident in a Brabender Plasticorder. The formulated polymers were molded in the form of sheets in a compression molder. Cut samples from the molded sheets were exposed in a weatherometer and tested on Instron Tensile Tester for strength and elongation. Specially molded samples of the formulated polymers were subjected to Charpy Impact Tests. In the second study, preliminary evaluations of adhesives for improvement of bonding between Teflon and stainless steel (SS) were performed. Kapton, a high temperature polyimide made by Dupont, and a rubber based adhesive made by Potter Paint Co., were evaluated against industrial quality epoxy, the current material used to bond Teflon and SS. The degreased surfaces of the SS discs were etched mechanically, with a few of these etched chemically. The surfaces of the SS discs were etched mechanically, with a few of these etched chemically. Bonding strengths were evaluated using lap shear tests on the Instron Tensile Tester for the samples bonded by Kapton and industrial quality epoxy. Bond strengths were also evaluated using a pull test on the Instron for the samples bonded by Potter adhesive (CWL-152) and industrial quality epoxy. Based on limited lap shear data, Kapton gave bond strength favorable compared to that of industrial epoxy. Based on limited pull test data, Kapton bonded and CWL-152 bonded samples showed poor strength compared to epoxy bonded sample.

Internal coating of zirconia restoration with silica-based ceramic improves bonding of resin cement to dental zirconia ceramic.

PubMed

Kitayama, Shuzo; Nikaido, Toru; Ikeda, Masaomi; Alireza, Sadr; Miura, Hiroyuki; Tagami, Junji

2010-01-01

Resin bonding to zirconia ceramic cannot be established by standard methods that are utilized for conventional silica-based dental ceramics. This study was aimed to examine the tensile bond strength of resin cement to zirconia ceramic using a new laboratory technique. Sixty-four zirconia ceramic specimens were air-abraded using Al2O3 particles and divided into two groups; the control group with no pretreatment (Control), and the group pretreated using the internal coating technique (INT), in which the surface of the zirconia specimens were thinly coated by fusing silica-based ceramic and air-abraded in the same manner. The specimens in each group were further divided into two subgroups according to the silane coupling agents applied; a mixture of dentin primer/silane coupling agent (Clearfil SE Bond Primer/Porcelain Bond Activator) or a newly developed single-component silane coupling agent (Clearfil Ceramic Primer). After bonding with dual-cured resin cement (Panavia F 2.0), they were stored in water for 24 h and half of them were additionally subjected to thermal cycling. The tensile bond strengths were tested using a universal testing machine. ANOVAs revealed significant influence of ceramic surface pretreatment (p<0.001), silane coupling agent (p<0.001) and thermal cycling (p<0.001); the INT coating technique significantly increased the bond strengths of resin cement to zirconia ceramic, whereas thermal cycling significantly decreased the bond strengths. The use of a single-component silane coupling agent demonstrated significantly higher bond strengths than that of a mixture of dentin primer/silane coupling agent. The internal coating of zirconia dental restorations with silica-based ceramic followed by silanization may be indicated in order to achieve better bonding for the clinical success.

The incorporation of chlorhexidine in a two-step self-etching adhesive preserves dentin bond in vitro.

PubMed

Zhou, Jianfeng; Tan, Jianguo; Chen, Li; Li, Deli; Tan, Yao

2009-10-01

To investigate whether the incorporation of chlorhexidine in a two-step self-etching adhesive can preserve dentin bond strengths. Different amounts of 20% chlorhexidine digluconate were added directly to the primer of Clearfil SE Bond to prepare mixtures of four different concentrations of chlorhexidine: 0.05%, 0.1%, 0.5% and 1.0%. Sixteen extracted third molars were randomly divided into 4 groups. Each group corresponded to one of the four chlorhexidine concentrations. Each of the 16 teeth was sectioned into two halves. One half was bonded with Clearfil SE Bond without chlorhexidine, and the other half was bonded with Clearfil SE Bond containing different concentrations of chlorhexidine. Specimens were stored in 0.9% NaCl containing 0.02% sodium azide at 37 degrees C. Microtensile bond strengths were tested 24h after specimen preparation or 12 months later. The modes of fractures were examined under a stereomicroscope. Twelve-month storage resulted in significant bond strength reduction of all control groups (p<0.05). When incorporated in SE Bond primer, chlorhexidine preserved dentin bond in the 0.1%, 0.5% and 1.0% chlorhexidine group (p<0.05); in the 0.05% group, there is no statistical difference of bond strength between control group and experimental group tested at the 12-month period (p>0.05). When incorporated in the primer of Clearfil SE Bond, chlorhexidine can preserve dentin bond as long as the concentration of chlorhexidine in the primer is higher than or equal to 0.1%.

Repair Bond Strength of Aged Resin Composite after Different Surface and Bonding Treatments

PubMed Central

Wendler, Michael; Belli, Renan; Panzer, Reinhard; Skibbe, Daniel; Petschelt, Anselm; Lohbauer, Ulrich

2016-01-01

The aim of this study was to compare the effect of different mechanical surface treatments and chemical bonding protocols on the tensile bond strength (TBS) of aged composite. Bar specimens were produced using a nanohybrid resin composite and aged in distilled water for 30 days. Different surface treatments (diamond bur, phosphoric acid, silane, and sandblasting with Al2O3 or CoJet Sand), as well as bonding protocols (Primer/Adhesive) were used prior to application of the repair composite. TBS of the specimens was measured and the results were analyzed using analysis of variance (ANOVA) and the Student–Newman–Keuls test (α = 0.05). Mechanically treated surfaces were characterized under SEM and by profilometry. The effect of water aging on the degree of conversion was measured by means of FTIR-ATR spectroscopy. An important increase in the degree of conversion was observed after aging. No significant differences in TBS were observed among the mechanical surface treatments, despite variations in surface roughness profiles. Phosphoric acid etching significantly improved repair bond strength values. The cohesive TBS of the material was only reached using resin bonding agents. Application of an intermediate bonding system plays a key role in achieving reliable repair bond strengths, whereas the kind of mechanical surface treatment appears to play a secondary role. PMID:28773669

Initiated chemical vapor deposited nanoadhesive for bonding National Ignition Facility's targets

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Tom

Currently, the target fabrication scientists in National Ignition Facility Directorate at Lawrence Livermore National Laboratory (LLNL) is studying the propagation force resulted from laser impulses impacting a target. To best study this, they would like the adhesive used to glue the target substrates to be as thin as possible. The main objective of this research project is to create adhesive glue bonds for NIF’s targets that are ≤ 1 μm thick. Polyglycidylmethacrylate (PGMA) thin films were coated on various substrates using initiated chemical vapor deposition (iCVD). Film quality studies using white light interferometry reveal that the iCVD PGMA films weremore » smooth. The coated substrates were bonded at 150 °C under vacuum, with low inflow of Nitrogen. Success in bonding most of NIF’s mock targets at thicknesses ≤ 1 μm indicates that our process is feasible in bonding the real targets. Key parameters that are required for successful bonding were concluded from the bonding results. They include inert bonding atmosphere, sufficient contact between the PGMA films, and smooth substrates. Average bond strength of 0.60 MPa was obtained from mechanical shearing tests. The bonding failure mode of the sheared interfaces was observed to be cohesive. Future work on this project will include reattempt to bond silica aerogel to iCVD PGMA coated substrates, stabilize carbon nanotube forests with iCVD PGMA coating, and kinetics study of PGMA thermal crosslinking.« less

Role of enamel deminerlization and remineralization on microtensile bond strength of resin composite

PubMed Central

Rizvi, Abbas; Zafar, Muhammad S.; Al-Wasifi, Yasser; Fareed, Wamiq; Khurshid, Zohaib

2016-01-01

Objective: This study is aimed to establish the microtensile bond strength of enamel following exposure to an aerated drink at various time intervals with/without application of remineralization agent. In addition, degree of remineralization and demineralization of tooth enamel has been assessed using polarized light microscopy. Materials and Methods: Seventy extracted human incisors split into two halves were immersed in aerated beverage (cola drink) for 5 min and stored in saliva until the time of microtensile bond testing. Prepared specimens were divided randomly into two study groups; remineralizing group (n = 70): specimens were treated for remineralization using casein phosphopeptides and amorphous calcium phosphate (CPP-ACP) remineralization agent (Recaldent™; GC Europe) and control group (n = 70): no remineralization treatment; specimens were kept in artificial saliva. All specimens were tested for microtensile bond strength at regular intervals (1 h, 1 days, 2 days, 1 week, and 2 weeks) using a universal testing machine. The results statistically analyzed (P = 0.05) using two-way ANOVA test. Results: Results showed statistically significant increase in bond strength in CPP-ACP tested group (P < 0.05) at all-time intervals. The bond strength of remineralizing group samples at 2 days (~13.64 megapascals [MPa]) is comparable to that of control group after 1 week (~12.44 MPa). Conclusions: CPP-ACP treatment of teeth exposed to an aerated drink provided significant increase in bond strength at a shorter interval compared to teeth exposed to saliva alone. PMID:27403057

Mechanical Strength and Failure Characterization of Sn-Ag-Cu Intermetallic Compound Joints at the Microscale

NASA Astrophysics Data System (ADS)

Ladani, Leila; Razmi, Jafar

2012-03-01

Continuous miniaturization of microelectronic devices has led the industry to develop interconnects on the order of a few microns for advanced superhigh-density and three-dimensional integrated circuits (3D ICs). At this scale, interconnects that conventionally consist of solder material will completely transform to intermetallic compounds (IMCs) such as Cu6Sn5. IMCs are brittle, unlike conventional solder materials that are ductile in nature; therefore, IMCs do not experience large amounts of plasticity or creep before failure. IMCs have not been fully characterized, and their mechanical and thermomechanical reliability is questioned. This study presents experimental efforts to characterize such material. Sn-based microbonds are fabricated in a controlled environment to assure complete transformation of the bonds to Cu6Sn5 IMC. Microstructural analysis including scanning electron microscopy (SEM), energy-dispersive x-ray spectroscopy (EDS), and x-ray diffraction (XRD) is utilized to determine the IMC material composition and degree of copper diffusion into the bond area. Specimens are fabricated with different bond thicknesses and in different configurations for various tests. Normal strength of the bonds is measured utilizing double cantilever beam and peeling tests. Shear tests are conducted to quantify the shear strength of the material. Four-point bending tests are conducted to measure the fracture toughness and critical energy release rate. Bonds are fabricated in different sizes, and the size effect is investigated. The shear strength, normal strength, critical energy release rate, and effect of bond size on bond strength are reported.

Prototype to measure bracket debonding force in vivo.

PubMed

Tonus, Jéssika Lagni; Manfroi, Fernanda Borguetti; Borges, Gilberto Antonio; Grigolo, Eduardo Correa; Helegda, Sérgio; Spohr, Ana Maria

2017-02-01

Material biodegradation that occurs in the mouth may interfere in the bonding strength between the bracket and the enamel, causing lower bond strength values in vivo, in comparison with in vitro studies. To develop a prototype to measure bracket debonding force in vivo and to evaluate, in vitro, the bond strength obtained with the prototype. A original plier (3M Unitek) was modified by adding one strain gauge directly connected to its claw. An electronic circuit performed the reading of the strain gauge, and the software installed in a computer recorded the values of the bracket debonding force, in kgf. Orthodontic brackets were bonded to the facial surface of 30 bovine incisors with adhesive materials. In Group 1 (n = 15), debonding was carried out with the prototype, while tensile bond strength testing was performed in Group 2 (n = 15). A universal testing machine was used for the second group. The adhesive remnant index (ARI) was recorded. According to Student's t test (α = 0.05), Group 1 (2.96 MPa) and Group 2 (3.08 MPa) were not significantly different. ARI score of 3 was predominant in the two groups. The prototype proved to be reliable for obtaining in vivo bond strength values for orthodontic brackets.

Bond strength of Bis-GMA and glass ionomer pit and fissure sealants using cyclic fatigue.

PubMed

Dewji, H R; Drummond, J L; Fadavi, S; Punwani, I

1998-02-01

The aim of the study was to determine the bond strength of glass ionomer and resin-modified glass ionomer sealants compared to Bis-GMA sealants using both static and cyclic fatigue shear testing. Four materials were evaluated: D, a Bis-GMA sealant with 10% phosphoric acid etchant; FC, a resin-modified glass ionomer sealant with 20% polyacrylic acid etchant; FD, a resin-modified glass ionomer sealant with 10% polyacrylic acid etchant; and FSC, a self-cured glass ionomer sealant with no etchant. Gelatin capsules filled with the sealant material were bonded to the enamel surfaces of bovine teeth after appropriate surface conditioning and then tested in shear static and cyclic fatigue. Static and cyclic shear bond strengths, respectively, for each group were (MPa): FC: 21.1+/-2.8 and 17.1+/-3.1; FD: 14.6+/-5.9 and 8.5+/-3.1; D: 10.8+/-4.9 and 4.7+/-2.6; FSC: 8.7 (1.0 and 2.9+/-0.6. The resin-modified glass ionomer sealants had better fatigue bond strength than both Bis-GMA and self-cured glass ionomer sealants with the surface conditioning affecting the bond strength of the resin-modified glass ionomer sealants.

Tensile bond strength of silicone-based soft denture liner to two chemically different denture base resins after various surface treatments.

PubMed

Akin, Hakan; Tugut, Faik; Guney, Umit; Kirmali, Omer; Akar, Turker

2013-01-01

This study evaluated the effect of various surface treatments on the tensile bond strength of a silicone-based soft denture liner to two chemically different denture base resins, heat-cured polymethyl methacrylate (PMMA), and light-activated urethane dimethacrylate or Eclipse denture base resin. PMMA test specimens were fabricated and relined with a silicone-based soft denture liner (group AC). Eclipse test specimens were prepared according to the manufacturer's recommendation. Before they were relined with a silicone-based soft denture liner, each received one of three surface treatments: untreated (control, group EC), Eclipse bonding agent applied (group EB), and laser-irradiated (group EL). Tensile bond strength tests (crosshead speed = 5 mm/min) were performed for all specimens, and the results were analyzed using the analysis of variance followed by Tukey's test (p = 0.05). Eclipse denture base and PMMA resins presented similar bond strengths to the silicone-based soft denture liner. The highest mean force was observed in group EL specimens, and the tensile bond strengths in group EL were significantly different (p < 0.05) from those in the other groups.

Phosphoric and carboxylic methacrylate esters as bonding agents in self-adhesive resin cements

PubMed Central

Liu, Wenshu; Meng, Hongmei; Sun, Zhiguang; Jiang, Riwen; Dong, Chang-An; Zhang, Congxiao

2018-01-01

The aim of the present study was to investigate the effect of pH and phosphoric ester structure (phosphonate or phosphate) on the bond strength of different dental restorative materials. The following three self-adhesive resin cements were used in the present study: RelyX™ Unicem, Maxcem and Multilink Sprint The pH of each cement was measured using a pH meter. The cements were used to attach a variety of restorative materials to human dentin and the bond strength was measured by assessing shear strength using a universal testing machine. The pH values of RelyX Unicem, Maxcem and Multilink Sprint were 3.78, 1.78 and 3.42, respectively. Maxcem, a phosphate-based self-adhesive cement, was demonstrated to form the weakest bonds. No significant difference in bond strength was observed between RelyX Unicem and Multilink Sprint, which are phosphonate-based cements. The results of the present study suggest that the chemical structure of the functional monomer influences the performance of an adhesive material. Furthermore, the pH of acidic functional monomers containing phosphonate or phosphate groups has an effect on the strength of bonds formed between dentin and restorative materials. PMID:29731837

[Effect of silicon coating on bonding strength of ceramics and titanium].

PubMed

Zhou, Shu; Wang, Yu; Zhang, Fei-Min; Guang, Han-Bing

2009-06-01

This study investigated the effect of silicon coating (SiO2) by solution-gelatin (Sol-Gel) technology on bonding strength of titanium and ceramics. Sixteen pure titanium specimens with the size of 25 mm x 3 mm x 0.5 mm were divided into two groups (n=8), test group was silicon coated by Sol-Gel technology, the other one was control group. The middle area of the samples were veneered with Vita Titankeramik system, the phase composition of two specimens were characterized by X-ray diffraction (XRD). The bonding strength of titanium/porcelain was evaluated using three-point bending test. The interface of titanium and porcelain and fractured titanium surface were investigated by scanning electron microscope (SEM) with energy depressive spectrum (EDS). Contents of surface silicon increased after modification with silicon coated by Sol-Gel technology. The mean bonding strength of test group and control group were (37.768 +/- 0.777) MPa and (29.483 +/- 1.007) MPa. There was a statistically significant difference (P=0.000) between them. The bonded ceramic boundary of test group was wider than control group. Silicon coating by Sol-Gel technology was significant in improving bonding strength of titanium/Vita Titankeramik system.

Shear bond strength of indirect composite material to monolithic zirconia.

PubMed

Sari, Fatih; Secilmis, Asli; Simsek, Irfan; Ozsevik, Semih

2016-08-01

This study aimed to evaluate the effect of surface treatments on bond strength of indirect composite material (Tescera Indirect Composite System) to monolithic zirconia (inCoris TZI). Partially stabilized monolithic zirconia blocks were cut into with 2.0 mm thickness. Sintered zirconia specimens were divided into different surface treatment groups: no treatment (control), sandblasting, glaze layer & hydrofluoric acid application, and sandblasting + glaze layer & hydrofluoric acid application. The indirect composite material was applied to the surface of the monolithic zirconia specimens. Shear bond strength value of each specimen was evaluated after thermocycling. The fractured surface of each specimen was examined with a stereomicroscope and a scanning electron microscope to assess the failure types. The data were analyzed using one-way analysis of variance (ANOVA) and Tukey LSD tests (α=.05). Bond strength was significantly lower in untreated specimens than in sandblasted specimens (P<.05). No difference between the glaze layer and hydrofluoric acid application treated groups were observed. However, bond strength for these groups were significantly higher as compared with the other two groups (P<.05). Combined use of glaze layer & hydrofluoric acid application and silanization are reliable for strong and durable bonding between indirect composite material and monolithic zirconia.

Effect of sandblasting on surface roughness of zirconia-based ceramics and shear bond strength of veneering porcelain.

PubMed

He, Min; Zhang, Zutai; Zheng, Dongxiang; Ding, Ning; Liu, Yan

2014-01-01

This study aims to investigate the effect of sandblasting on the surface roughness of zirconia and the shear bond strength of the veneering porcelain. Pre-sintered zirconia plates were prepared and divided into four groups. Group A were not treated at all; group B were first sandblasted under 0.2 MPa pressure and then densely sintered; group C and D were sintered first, and then sandblasted under 0.2 MPa and 0.4 MPa pressures respectively. Surface roughness was measured and 3D roughness was reconstructed for the specimens, which were also analyzed with X-ray diffractometry. Finally after veneering porcelain sintering, shear bond tests were conducted. Sandblasting zirconia before sintering significantly increased surface roughness and the shear bond strength between zirconia and veneering porcelain (p<0.05). Sandblasting zirconia before sintering is a useful method to increase surface roughness and could successfully improve the bonding strength of veneering porcelain.

Shear bond strength in zirconia veneered ceramics using two different surface treatments prior veneering.

PubMed

Gasparić, Lana Bergman; Schauperl, Zdravko; Mehulić, Ketij

2013-03-01

Aim of the study was to assess the effect of different surface treatments on the shear bond strength (SBS) of the veneering ceramics to zirconia core. In a shear test the influence of grinding and sandblasting of the zirconia surface on bonding were assessed. Statistical analysis was performed using SPSS statistical package (version 17.0, SPSS Inc., Chicago, IL, USA) and Microsoft Office Excel 2003 (Microsoft, Seattle, WA, USA). There was a significant difference between the groups considering shear bond strength (SBS) values, i.e. ground and sandblasted samples had significantly higher SBS values than only ground samples (mean difference = -190.67; df = 10, t = -6.386, p < 0.001). The results of the present study indicate that ground and sandblasted cores are superior to ground cores, allowing significantly higher surface roughness and significantly higher shear bond strength between the core and the veneering material.

Evaluation of a conditioning method to improve core-veneer bond strength of zirconia restorations.

PubMed

Teng, Jili; Wang, Hang; Liao, Yunmao; Liang, Xing

2012-06-01

The high strength and fracture toughness of zirconia have supported its extensive application in esthetic dentistry. However, the fracturing of veneering porcelains remains one of the primary causes of failure. The purpose of this study was to evaluate, with shear bond strength testing, the effect of a simple and novel surface conditioning method on the core-veneer bond strength of a zirconia ceramic system. The shear bond strength of a zirconia core ceramic to the corresponding veneering porcelain was tested by the Schmitz-Schulmeyer method. Thirty zirconia core specimens (10 × 5 × 5 mm) were layered with a veneering porcelain (5 × 3 × 3 mm). Three different surface conditioning methods were evaluated: polishing with up to 1200 grit silicon carbide paper under water cooling, airborne-particle abrasion with 110 μm alumina particles, and modification with zirconia powder coating before sintering. A metal ceramic system was used as a control group. All specimens were subjected to shear force in a universal testing machine at a crosshead speed of 0.5 mm/min. The shear bond strength values were analyzed with 1-way ANOVA and Tukey's post hoc pairwise comparisons (α=.05). The fractured specimens were examined with a scanning electron microscope to observe the failure mode. The mean (SD) shear bond strength values in MPa were 47.02 (6.4) for modified zirconia, 36.66 (8.6) for polished zirconia, 39.14 (6.5) for airborne-particle-abraded zirconia, and 46.12 (7.1) for the control group. The mean bond strength of the control (P=.028) and modified zirconia groups (P=.014) was significantly higher than that of the polished zirconia group. The airborne-particle-abraded group was not significantly different from any other group. Scanning electron microscopy evaluation showed that cohesive fracture in the veneering porcelain was the predominant failure mode of modified zirconia, while the other groups principally fractured at the interface. Modifying the zirconia surface with powder coating could significantly increase the shear bond strength of zirconia to veneering porcelain. Copyright © 2012 The Editorial Council of the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.

What holds paper together: Nanometre scale exploration of bonding between paper fibres

PubMed Central

Schmied, Franz J.; Teichert, Christian; Kappel, Lisbeth; Hirn, Ulrich; Bauer, Wolfgang; Schennach, Robert

2013-01-01

Paper, a man-made material that has been used for hundreds of years, is a network of natural cellulosic fibres. To a large extent, it is the strength of bonding between these individual fibres that controls the strength of paper. Using atomic force microscopy, we explore here the mechanical properties of individual fibre-fibre bonds on the nanometre scale. A single fibre-fibre bond is loaded with a calibrated cantilever statically and dynamically until the bond breaks. Besides the calculation of the total energy input, time dependent processes such as creep and relaxation are studied. Through the nanometre scale investigation of the formerly bonded area, we show that fibrils or fibril bundles play a crucial role in fibre-fibre bonding because they act as bridging elements. With this knowledge, new fabrication routes can be deduced to increase the strength of an ancient product that is in fact an overlooked high-tech material. PMID:23969946

Effects of partial interlaminar bonding on impact resistance and loaded-hole behavior of graphite/epoxy quasi-isotropic laminates

NASA Technical Reports Server (NTRS)

Illg, W.

1986-01-01

A partial-bonding interlaminar toughening concept was evaluated for resistance to impact and for behavior of a loaded hole. Perforated Mylar sheets were interleaved between all 24 plies of a graphite/epoxy quasi-isotropic lay-up. Specimens were impacted by aluminum spheres while under tensile or compressive loads. Impact-failure thresholds and residual strengths were obtained. Loaded-hole specimens were tested in three configurations that were critical in bearing, shear, or tension. Partial bonding reduced the tensile and compressive strengths of undamaged specimens by about one-third. For impact, partial bonding did not change the threshold for impact failure under tensile preload. However, under compressive preload, partial bonding caused serious degradation of impact resistance. Partial bonding reduced the maximum load-carrying capacity of all three types of loaded-hole specimens. Overall, partial bonding degraded both impact resistance and bearing strength of holes.

Resin cementation of zirconia ceramics with different bonding agents

PubMed Central

Tanış, Merve Çakırbay; Akay, Canan; Karakış, Duygu

2015-01-01

The aim of this study was to evaluate the effects of sandblasting and different chemical bonding agents on shear bond strength of zirconia and conventional resin cement. In this study, 35 zirconia specimens were treated as follows: Group I: control; Group II: sandblasting; Group III: sandblasting + Monobond S; Group IV: sandblasting + Monobond Plus; Group V: sandblasting + Z-Prime Plus. The specimens in each group were bonded with conventional composite resin cement Variolink II. After cementation, specimens were stored in distilled water (at 37 °C) for 24 h and shear test was performed. The highest shear bond strength values were observed in Groups IV and V. The lowest shear bond strength values were observed in Group I. Using 10-methacryloyloxy-decyl dihydrogenphosphate monomer-containing priming agents, e.g. Monobond Plus and Z-PRIME Plus, combined with sandblasting can be an effective method for resin bonding of zirconia restorations. PMID:26019653

Bond and fracture strength of metal-ceramic restorations formed by selective laser sintering

PubMed Central

Bae, Eun-Jeong; Kim, Woong-Chul; Kim, Hae-Young

2014-01-01

PURPOSE The purpose of this study was to compare the fracture strength of the metal and the bond strength in metal-ceramic restorations produced by selective laser sintering (SLS) and by conventional casting (CAST). MATERIALS AND METHODS Non-precious alloy (StarLoy C, DeguDent, Hanau, Germany) was used in CAST group and metal powder (SP2, EOS GmbH, Munich, Germany) in SLS group. Metal specimens in the form of sheets (25.0 × 3.0 × 0.5 mm) were produced in accordance with ISO 9693:1999 standards (n=30). To measure the bond strength, ceramic was fired on a metal specimen and then three-point bending test was performed. In addition, the metal fracture strength was measured by continuing the application of the load. The values were statistically analyzed by performing independent t-tests (α=.05). RESULTS The mean bond strength of the SLS group (50.60 MPa) was higher than that of the CAST group (46.29 MPa), but there was no statistically significant difference. The metal fracture strength of the SLS group (1087.2 MPa) was lower than that of the CAST group (2399.1 MPa), and this difference was statistically significant. CONCLUSION In conclusion the balling phenomenon and the gap formation of the SLS process may increase the metal-ceramic bond strength. PMID:25177469

Effect of surface contamination on adhesive bonding of cast pure titanium and Ti-6Al-4V alloy.

PubMed

Watanabe, I; Watanabe, E; Yoshida, K; Okabe, T

1999-03-01

There is little information regarding bond strengths of resin cements to cast titanium surfaces contaminated by investment material. This study examined the effect of surface contamination on the shear bond strength of resin cements to cast titanium and Ti-6Al-4V alloy. Two types of disks were cast from commercially pure titanium (CP-Ti) and Ti-6Al-4V alloy ingots using an argon-arc pressure casting unit and a phosphate-bonded Al2 O3 /LiAlSiO6 investment. After casting, disks were subjected to 3 surface treatments: (1) cast surface sandblasted (50 microm-sized Al2 O3 ) for 30 seconds; (2) metal surface sanded with silicon-carbide paper (600 grit) after grinding the contaminated cast surface (approximately 200 microm in thickness); and (3) metal surface sandblasted for 30 seconds after treatment 2. Surface structures were examined after each treatment with SEM and optical microscopy. Each type of disk was then bonded with 2 types of luting materials. Bonded specimens were subjected to thermocycling for up to 50,000 cycles, and shear bond strengths were determined after 0 (baseline) and 50,000 thermocycles. Results were statistically analyzed with 3-way ANOVA (P <.05). Microscopic observation of cast CP-Ti and Ti-6Al-4V exhibited noticeable structures on the cast surfaces apparently contaminated with investment material. However, there were no statistical differences (P >.05) in the bond strengths of both cements between contaminated (treatment 1) and uncontaminated surfaces (treatment 3) for both metals at baseline and after 50,000 thermocycles. The bond strength of specimens sanded with silicon-carbide paper (treatment 2) deteriorated dramatically after 50,000 thermocycles. Contamination of the cast metal surfaces by elements of the investment during casting did not affect bond strengths of the luting materials to CP-Ti and Ti-6Al-4V.

Micro-shear bond strengths of adhesive resins to coronal dentin versus the floor of the pulp chamber.

PubMed

Toba, Shigemitsu; Veerapravati, Weeraporn; Shimada, Yasushi; Nikaido, Toru; Tagami, Junji

2003-09-01

To evaluate the micro-shear bond strengths to superficial coronal dentin and the floor of the pulp chamber using two dentin bonding systems and to compare the ultrastructure of the resin-dentin interface of the two regions. 30 non-carious molars were used to obtain 2 mm thick slabs of coronal dentin and dentin at the pulp chamber. The specimens in each region were divided into three sub-groups to be bonded as follows; Clearfil SE Bond was used according to the manufacturer's instructions, Single Bond was applied to either wet dentin (Blot dry Group) or air-dried dentin (Dry Group) after phosphoric acid etching. A resin composite cylinder 0.5 mm high and 0.75 mm in diameter formed using a vinyl tube was bonded to the dentin. Specimens were stored at 37 degrees C for 24 hours in water and then stressed in shear at a crosshead speed of 1 mm/minute. The data were analyzed with one-way ANOVA and Fisher's PLSD test at the 5% level of significance. In addition, the ultrastructure of cross-sectioned dentin surfaces, the conditioned dentin surface and the resin dentin interfaces were observed by SEM. The bond strengths of Clearfil SE Bond and the Single Bond Blot dry group were approximately 40 MPa in coronal dentin and 30 MPa in the dentin at the floor of the pulp chamber respectively. However, the bond strengths of Single Bond were significantly lower in the Dry condition (MPa) (P < 0.05). SEM observations revealed the thickness of the hybrid layer created by Clearfil SE Bond in coronal dentin and at the floor of the pulp chamber were less than 1.0 microm thick. For Single Bond, a 3-4 microm hybrid layer was created in coronal dentin, while a thinner hybrid layer was observed in the floor of the pulp chamber. Morphological and structural variations in dentin may have influenced the bond strengths of the bonding systems to the floor of the pulp chamber.

Effects of metal primers on the bonding of an adhesive resin cement to noble metal ceramic alloys after thermal cycling.

PubMed

Minami, Hiroyuki; Murahara, Sadaaki; Suzuki, Shiro; Tanaka, Takuo

2011-12-01

Although the effectiveness of primers for resin bonding to noble alloys has been demonstrated, no effective clinical technique for bonding to noble metal ceramic alloys has been established. The purpose of this study was to evaluate the effects of metal primers on the shear bond strength of an adhesive resin to noble metal ceramic alloys after thermal cycling. Sixty-three disk-shaped specimens (10 × 2.5 mm) were cast from high-gold-content alloys (Super Metal W-85: W85 or IFK88 GR: IFK88), a high-palladium-content alloy (Super Metal N-40: N40), and an Ag-Pd-Cu-Au alloy (Castwell M.C.12: MC12). Smaller-sized disk-shaped specimens (8 × 2.5 mm) were fabricated with MC12. Bonding surfaces were finished with 600-grit SiC-paper and airborne-particle abraded with 50-μm alumina. Pairs of disks were primed (V-Primer: VP; ML Primer: ML; or Metaltite: MT) and bonded with an adhesive resin (Super-Bond C&B). The bond strengths were determined before and after 20,000 and 50,000 thermal cycles (n=7). Data were analyzed by using a 3-way ANOVA and the Bonferroni test (α=.05). Failure modes were determined by optical microscope and SEM observation. Bond strengths to high-gold-content alloys with VP and MT significantly decreased after the thermal cycling (P<.001). Bond strengths to W85 (35.27 ±4.25 MPa) and IFK88 (33.57 ±3.56 MPa) after 50,000 thermal cycles obtained by ML were the highest (P<.001), and these groups showed combination failures. Bond strengths to N40 significantly decreased after 50,000 thermal cycles (P<.001), regardless of primers. Shear bond strengths (SBS) to high-gold-content alloys were not degraded up to 50,000 thermal cycles when primed with ML. None of the primers evaluated was effective for high-palladium-content alloy. Copyright © 2011 The Editorial Council of the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.

Comparative efficacy of Er,Cr:YSGG and Er:YAG lasers for etching of composite for orthodontic bracket bonding.

PubMed

Mirhashemi, Amir Hossein; Chiniforush, Nasim; Sharifi, Nastaran; Hosseini, Amir Mehdi

2018-05-01

Several techniques have been proposed to obtain a durable bond, and the efficacy of these techniques is assessed by measuring parameters such as bond strength. Laser has provided a bond strength as high as that of acid etching in vitro and has simpler use with shorter clinical time compared to acid etching. This study aimed to compare the efficacy of Er:YAG and Er,Cr:YSGG lasers for etching and bonding of composite to orthodontic brackets. No previous study has evaluated the effect of these particular types of laser. A total of 70 composite blocks were randomly divided into five groups (n = 14): group 1, etching with phosphoric acid for 20 s; group 2, Er:YAG laser irradiation with 2 W power for 10 s; group 3, Er:YAG laser with 3 W power for 10 s; group 4, Er,Cr:YSGG laser with 2 W power for 10 s; group 5, Er,Cr:YSGG laser with 3 W power for 10 s. Metal brackets were then bonded to composites, and after 5000 thermal cycles, they were subjected to shear bond strength test in a universal testing machine after 24 h of water storage. One sample of each group was evaluated under a scanning electron microscope (SEM) to assess changes in composite surface after etching. The adhesive remnant index (ARI) was calculated under a stereomicroscope. Data were statistically analyzed. The mean and standard deviation of shear bond strength were 18.65 ± 3.36, 19.68 ± 5.34, 21.31 ± 4.03, 17.38 ± 6.94, and 16.45 ± 4.26 MPa in groups 1-5, respectively. The ARI scores showed that the bond failure mode in all groups was mainly mixed. The groups were not significantly different in terms of shear bond strength. Er:YAG and Er,Cr:YSGG lasers with the mentioned parameters yield optimal shear bond strength and can be used as an alternative to acid etching for bracket bond to composite.

Reliability of the pair-defect-sum approximation for the strength of valence-bond orbitals

PubMed Central

Pauling, Linus; Herman, Zelek S.; Kamb, Barclay J.

1982-01-01

The pair-defect-sum approximation to the bond strength of a hybrid orbital (angular wave functions only) is compared to the rigorous value as a function of bond angle for seven types of bonding situations, with between three and eight bond directions equivalent by geometrical symmetry operations and with only one independent bond angle. The approximation is seen to be an excellent one in all cases, and the results provide a rationale for the application of this approximation to a variety of problems. PMID:16593167

Drying time of tray adhesive for adequate tensile bond strength between polyvinylsiloxane impression and tray resin material.

PubMed

Yi, Myong-Hee; Shim, Joon-Sung; Lee, Keun-Woo; Chung, Moon-Kyu

2009-07-01

Use of custom tray and tray adhesive is clinically recommended for elastomeric impression material. However there is not clear mention of drying time of tray adhesive in achieving appropriate bonding strength of tray material and impression material. This study is to investigate an appropriate drying time of tray adhesives by evaluating tensile bonding strength between two types of polyvinylsiloxane impression materials and resin tray, according to various drying time intervals of tray adhesives, and with different manufacturing company combination of impression material and tray adhesive. Adhesives used in this study were Silfix (Dentsply Caulk, Milford, Del, USA) and VPS Tray Adhesive (3M ESPE, Seefeld, Germany) and impression materials were Aquasil Ultra (monophase regular set, Dentsply Caulk, Milford, Del, USA) and Imprint II Garant (regular body, 3M ESPE, Seefeld, Germany). They were used combinations from the same manufacture and exchanged combinations of the two. The drying time was designed to air dry, 5 minutes, 10 minutes, 15 minutes, 20 minutes, and 25 minutes. Total 240 of test specimens were prepared by auto-polymerizing tray material (Instant Tray Mix, Lang, Wheeling, Il, USA) with 10 specimens in each group. The specimens were placed in the Universal Testing machine (Instron, model 3366, Instron Corp, University avenue, Nowood, MA, USA) to perform the tensile test (cross head speed 5 mm/min). The statistically efficient drying time was evaluated through ANOVA and Scheffe test. All the tests were performed at 95% confidence level. The results revealed that at least 10 minutes is needed for Silfix-Aquasil, and 15 minutes for VPS Tray Adhesive-Imprint II, to attain an appropriate tensile bonding strength. VPS Tray Adhesive-Imprint II had a superior tensile bonding strength when compared to Silfix-Aquasil over 15 minutes. Silfix-Aquasil had a superior bonding strength to VPS Tray Adhesive-Aquasil, and VPS Tray Adhesive-Imprint II had a superior tensile bonding strength to Silfix-Imprint II at all drying periods. Significant increase in tensile bonding strength with Silfix-Aquasil and VPS Tray adhesive-Imprint II combination until 10 and 15 minutes respectively. Tray adhesive-impression material combination from the same company presented higher tensile bonding strength at all drying time intervals than when using tray adhesive-impression material of different manufactures.

Bond strength of primer/cement systems to zirconia subjected to artificial aging.

PubMed

Zhao, Li; Jian, Yu-Tao; Wang, Xiao-Dong; Zhao, Ke

2016-11-01

Creating reliable and durable adhesion to the nonactive zirconia surface is difficult and has limited zirconia use. The introduction of functional monomers such as 10-methacryloyloxydecyl dihydrogen phosphate (MDP) appears to have enhanced bond strength to zirconia. The purpose of this in vitro study was to evaluate the long-term bond strength of several MDP-containing primer/cement systems to zirconia. Zirconia blocks were divided into 6 groups (n=24) according to the 3 primers/cements to be bonded, as follows: Scotchbond Universal/RelyX Ultimate (SU/RU; consisting of MDP-containing primer/MDP-free cement); Clearfil ceramic primer/Panavia F (CCP/PAN; consisting ofMDP-containing/MDP-containing); and Z-Prime Plus/Duo-Link (ZP/DUO; consisting ofMDP-containing/MDP-free), which were compared with 3 nonprimed groups, RU, PAN, and DUO. After bonding, each group was further divided into 3 subgroups (n=8) according to the level of aging: 24-hour storage in water at 37°C (24H); 30-day storage at 37°C (30D); and 30-day storage at 37°C followed by 3000 thermal cycles (30D/TC). After aging, a shear bond strength test and failure mode analysis were performed. The data were analyzed using 2-way ANOVA (α=.05). After aging, nearly all primer/cement groups presented significantly higher bond strength than the related nonprimed groups for each level of aging (P<.05), except for CCP/PAN versus PAN with 24H (P=.741). SU/RU had the highest bond strength among the groups for all treatments (P<.05), except for CCP/PAN versus SU/RU with 30D/TC (P=.171). Among the nonprimed groups, only RU went through 30D/TC without premature debonding. With 24H and 30D, the failure modes in SU/RU and CCP/PAN were purely mixed, whereas those in the other groups were mainly adhesive, except for RU. The superiority of the initial bond strength in SU/RU may result from some functional components other than MDP. The presence of MDP in the cement did not appear to have a positive effect on long-term bond strength to zirconia. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Short and long term behaviour of externally bonded fibre reinforced polymer laminates with bio-based resins for flexural strengthening of concrete beams

NASA Astrophysics Data System (ADS)

McSwiggan, Ciaran

The use of bio-based resins in composites for construction is emerging as a way to reduce of embodied energy produced by a structural system. In this study, two types of bio-based resins were explored: an epoxidized pine oil resin blend (EP) and a furfuryl alcohol resin (FA) derived from corn cobs and sugar cane. Nine large-scale reinforced concrete beams strengthened using externally bonded carbon and glass fibre reinforced bio-based polymer (CFRP and GFRP) sheets were tested. The EP resin resulted in a comparable bond strength to conventional epoxy (E) when used in wet layup, with a 7% higher strength for CFRP. The FA resin, on the other hand, resulted in a very weak bond, likely due to concrete alkalinity affecting curing. However, when FA resin was used to produce prefabricated cured CFRP plates which were then bonded to concrete using conventional epoxy paste, it showed an excellent bond strength. The beams achieved an increase in peak load ranging from 18-54% and a 9-46% increase in yielding load, depending on the number of FRP layers and type of fibres and resin. Additionally, 137 concrete prisms with a mid-span half-depth saw cut were used to test CFRP bond durability, and 195 CFRP coupons were used to examine tensile strength durability. Specimens were conditioned in a 3.5% saline solution at 23, 40 or 50°C, for up to 240 days. Reductions in bond strength did not exceed 15%. Bond failure of EP was adhesive with traces of cement paste on CFRP, whereas that of FA was cohesive with a thicker layer of concrete on CFRP, suggesting that the bond between FA and epoxy paste is excellent. EP tension coupons had similar strength and modulus to E resin, whereas FA coupons had a 9% lower strength and 14% higher modulus. After 240 days of exposure, maximum reductions in tensile strength were 8, 19 and 10% for EP, FA and E resins, respectively. Analysis of Variance (ANOVA) was also performed to assess the significance of the reductions observed. High degrees of variability in the test results may have skewed the results from this statistical analysis.

The effect of different final irrigant activation techniques on the bond strength of an epoxy resin-based endodontic sealer: a preliminary study.

PubMed

Topçuoğlu, Hüseyin Sinan; Tuncay, Öznur; Demirbuga, Sezer; Dinçer, Asiye Nur; Arslan, Hakan

2014-06-01

The aim of this study was to evaluate whether or not different final irrigation activation techniques affect the bond strength of an epoxy resin-based endodontic sealer (AH Plus; Dentsply DeTrey, Konstanz, Germany) to the root canal walls of different root thirds. Eighty single-rooted human mandibular premolars were prepared by using the ProTaper system (Dentsply Maillefer, Ballaigues, Switzerland) to size F4, and a final irrigation regimen using 3% sodium hypochlorite and 17% EDTA was performed. The specimens were randomly divided into 4 groups (n = 20) according to the final irrigation activation technique used as follows: no activation (control), manual dynamic activation (MDA), CanalBrush (Coltene Whaledent, Altststten, Switzerland) activation, and ultrasonic activation. Five specimens from each group were prepared for scanning electron microscopic observation to assess the smear layer removal after the final irrigation procedures. All remaining roots were then obturated with gutta-percha and AH Plus sealer. A push-out test was used to measure the bond strength between the root canal dentin and AH Plus sealer. The data obtained from the push-out test were analyzed using 2-way analysis of variance and Tukey post hoc tests. The bond strength values mostly decreased in the coronoapical direction (P < .001). In the coronal and middle thirds, ultrasonic activiation showed a higher bond strength than other groups (P < .05). In the apical third, MDA displayed the highest bond strength to root dentin (P < .05). The majority of specimens exhibited cohesive failures. The bond strength of AH Plus sealer to root canal dentin may improve with ultrasonic activation in the coronal and middle thirds and MDA in the apical third. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Effect of laser welding on the titanium ceramic tensile bond strength.

PubMed

Galo, Rodrigo; Ribeiro, Ricardo Faria; Rodrigues, Renata Cristina Silveira; Pagnano, Valéria de Oliveira; Mattos, Maria da Glória Chiarello de

2011-08-01

Titanium reacts strongly with elements, mainly oxygen at high temperature. The high temperature of titanium laser welding modifies the surface, and may interfere on the metal-ceramic tensile bond strength. The influence of laser welding on the titanium-ceramic bonding has not yet been established. The purpose of this in vitro study was to analyze the influence of laser welding applied to commercially pure titanium (CpTi) substructure on the bond strength of commercial ceramic. The influence of airborne particle abrasion (Al2O3) conditions was also studied. Forty CpTi cylindrical rods (3 mm x 60 mm) were cast and divided into 2 groups: with laser welding (L) and without laser welding (WL). Each group was divided in 4 subgroups, according to the size of the particles used in airborne particle abrasion: A - Al2O3 (250 µm); B - Al2O3 (180 µm); C - Al2O3 (110 µm); D - Al2O3 (50 µm). Ceramic rings were fused around the CpTi rods. Specimens were invested and their tensile strength was measured at fracture with a universal testing machine at a crosshead speed of 2.0 mm/min and 200 kgf load cell. Statistical analysis was carried out with analysis of variance and compared using the independent t test (p<0.05). Significant differences were found among all subgroups (p<0.05). The highest and the lowest bond strength means were recorded in subgroups WLC (52.62 MPa) and LD (24.02 MPa), respectively. Airborne particle abrasion yielded significantly lower bond strength as the Al2O3 particle size decreased. Mechanical retention decreased in the laser-welded specimens, i.e. the metal-ceramic tensile bond strength was lower.

[Evaluation of the effect of modified wet particle erosion on bond strength between 3Y-TZP zirconia framework and veneering porcelain].

PubMed

Guo, Jing; Zhu, Jia; Liu, Hon-Guang; Zhu, Hong-Shui

2017-02-01

To evaluate the effect of bond strength between 3mol% yttrium-stabilized tetragonal zirconium polycrystal (3Y-TZP) zirconia framework after modified wet particle erosion and veneering porcelain. A total of 174 [8 mm× 8 mm× 3 mm (±0.02)] specimens were prepared and then randomly divided into different groups according to different particle size, sandblasting pressure, sandblasting time through conventional sandblasting (experimental groups); specimens in the control group were not sandblasted. The bond strength between 3Y-TZP zirconia framework and veneering porcelain was measured using a universal testing machine. Statistical analysis was performed using SPSS17.0 software package. The bond strength of specimens treated by two methods-conventional sandblasting and modified wet particle erosion under the same condition (150 μm, 0.6 MPa, 30 s) were acquired, while the surface was analyzed microscopically before the specimens were veneered with the veneering ceramic under scanning electronic microscope (SEM). The bond strength of conventional sandblasting group under the condition (110 μm, 0.4 MPa,30 s) was maximal, and significantly higher than the control group (P<0.05). The bond strength of modified wet particle erosion group was significantly higher than the conventional sandblasting group and control group (P<0.01); SEM showed that the surface of specimen with modified wet particle erosion was homogeneously rough; the surface specimen with conventional sandblasting was heterogeneously rough, some microcracks were seen in some areas. Sandblasting can slightly enhance the bond strength between 3Y-TZP zirconia framework and veneering porcelain, modified wet particle erosion is recommended for 3Y-TZP zirconia framework surface treatment.

[Effect of different heat treatment on the bonding strength of porcelain and Co-Cr alloy].

PubMed

Liao, Juan-kun; Ye, Jian-tao; Zhu, Feng; Zhang, Cui-cui; Wen, Xiao-shan; Zhang, Yi-ping; Li, Bo-hua

2011-12-01

To investigate and compare the effect of different heat treatment on the metal- ceramic bonding strength and the interfacial microstructure of the Co-Cr alloy. Thirty specimens were made according to ISO 9693,and then divided into 3 groups (n=10) through the measurements .Group A(degassed 60s):degassed and then maintained 60s in 980 degrees centigrade Group B(degassed 60s and preoxidation 60s): degassed and maintained 60s in 980 degrees centigrade, then were maintained continuously for 60s in 980 degrees centigrade after re-gassed,Group C(degassed 120s): degassed and maintained 120s in 980 degrees centigrade. The bonding strengths of the three groups were evaluated through three point bending test. Six specimens divided into 3 group were made in the same method to observe the metal-ceramic interface through scanning electronic microscope(SEM) and energy dispersive spectrum(EDS).The bonding strength data were analyzed using ANOVA and Bonferroni's test by SPSS13.0 software package. The mean value of bonding strength was (39.03±2.70)MPa for group A, (34.43±2.36)MPa for group B, (31.65±1.49)MPa for group C, respectively. There were significant difference between every two groups (P<0.05). SEM demonstrated that the width of interfacial transition layer was 12.3-16.4μm in group A, 15.2-21.8μm in group B and 26.3-32.2μm in group C. Higher metal-ceramic bonding strength for Co-Cr alloy will be formed under the situation of degassed,and maintained 60s in 980 degrees centigrade ; while extending degassed time, prolonging the heat maintained time and preoxidation after degassing will reduce metal-ceramic bonding strength.

Influence of oval and circular post placement using different resin cements on push-out bond strength and void volume analysed by micro-CT.

PubMed

Uzun, I; Keleş, A; Arslan, H; Güler, B; Keskin, C; Gündüz, K

2016-12-01

To evaluate the percentage volume of voids within cement layers, to determine the push-out bond strength of circular and oval fibre posts luted with different commercial resin cements in oval cross-sectional root canals, and to correlate push-out bond strength values and volume of voids of circular and oval fibre posts. Seventy-two mandibular premolars with oval-shaped root canals were selected. The specimens were divided into two main groups according to the post type (oval and circular). Groups were further divided into three subgroups (n = 24) according to resin cement type: Maxcem Elite, Rely-X Unicem and Duo-Link. The volumes of voids within the cements were analysed by micro-computed tomography (micro-CT). The bond strength was then measured using a push-out test with an Instron universal testing machine. The failure modes were evaluated. Statistical analyses were performed using a three-way anova, Tukey's post hoc, Pearson's correlation and chi-square test (P = 0.05). The push-out bond strength values were significantly affected by root canal region, post type and cement type (P < 0.001). Root canal region, post type and cement type also significantly affected void volume (P < 0.001). There was a significant interaction between post type and cement type (P < 0.001). The most frequent failure type was adhesive failure in all the groups. There was no significant correlation between the push-out bond strength and void volume (P > 0.05). Void volume did not affect push-out bond strength of oval and circular posts luted in oval canals. © 2015 International Endodontic Journal. Published by John Wiley & Sons Ltd.

The Impact of Plasma Treatment of Cercon® Zirconia Ceramics on Adhesion to Resin Composite Cements and Surface Properties.

PubMed

Tabari, Kasra; Hosseinpour, Sepanta; Mohammad-Rahimi, Hossein

2017-01-01

Introduction: In recent years, the use of ceramic base zirconia is considered in dentistry for all ceramic restorations because of its chemical stability, biocompatibility, and good compressive as well as flexural strength. However, due to its chemical stability, there is a challenge with dental bonding. Several studies have been done to improve zirconia bonding but they are not reliable. The purpose of this research is to study the effect of plasma treatment on bonding strength of zirconia. Methods: In this in vitro study, 180 zirconia discs' (thickness was 0.85-0.9 mm) surfaces were processed with plasma of oxygen, argon, air and oxygen-argon combination with 90-10 and 80-20 ratio (n=30 for each group) after being polished by sandblast. Surface modifications were assessed by measuring the contact angle, surface roughness, and topographical evaluations. Cylindrical Panavia f2 resin-cement and Diafill were used for microshear strength bond measurements. The data analysis was performed by SPSS 20.0 software and one-way analysis of variance (ANOVA) and Tukey test as the post hoc. Results: Plasma treatment in all groups significantly reduces contact angle compare with control ( P =0.001). Topographic evaluations revealed coarseness promotion occurred in all plasma treated groups which was significant when compared to control ( P <0.05), except argon plasma treated group that significantly decreased surface roughness ( P <0.05). In all treated groups, microshear bond strength increased, except oxygen treated plasma group which decreased this strength. Air and argon-oxygen combination (both groups) significantly increased microshear bond strength ( P <0.05). Conclusion: According to this research, plasmatic processing with dielectric barrier method in atmospheric pressure can increase zirconia bonding strength.

The effect of denture base surface pretreatments on bond strengths of two long term resilient liners

PubMed Central

Parkhedkar, Rambhau

2011-01-01

PURPOSE Purpose of this study was to evaluate effect of two surface treatments, sandblasting and monomer treatment, on tensile bond strength between two long term resilient liners and poly (methyl methacrylate) denture base resin. MATERIALS AND METHODS Two resilient liners Super-Soft and Molloplast-B were selected.Sixty acrylic resin (Trevalon) specimens with cross sectional area of 10×10 mm were prepared and divided into two groups of 30 specimens each. Each group was surface treated (n = 10) by sandblasting (250 µ alumina particles), monomer treatment (for 180 sec) and control (no surface treatment). Resilient liners were processed between 2 poly(methyl methacrylate) surfaces, in the dimensions of 10×10×3 mm. Tensile strength was determined with Instron Universal testing machine, at a crosshead speed of 5 mm/min; and the modes of failure (adhesive, cohesive or mixed) were recorded. The data were analyzed using one-way ANOVA, followed by Tukey HSD test (α = 0.05). RESULTS Monomer pretreatment of acrylic resin produced significantly higher bond strengths when compared to sandblasting and control for both resilient liners (P < .001). Sandblasting significantly decreased the bond strength for both the liners when compared to monomer pretreatment and control (P < .001). Mean bond strength of Super-Soft lined specimens was significantly higher than Molloplast-B in various surface treatment groups (P < .05). CONCLUSION Surface pretreatment of the acrylic resin with monomer prior to resilient liner application is an effective method to increase bond strength between the base and soft liner. Sandblasting, on the contrary, is not recommended as it weakens the bond between the two. PMID:21503188

Bond Strength of Resin Cements to Zirconia Ceramic Using Adhesive Primers.

PubMed

Stefani, Ariovaldo; Brito, Rui Barbosa; Kina, Sidney; Andrade, Oswaldo Scopin; Ambrosano, Gláucia Maria Bovi; Carvalho, Andreia Assis; Giannini, Marcelo

2016-07-01

To evaluate the influence of adhesive primers on the microshear bond strength of resin cements to zirconia ceramic. Fifty zirconia plates (12 mm × 5 mm × 1.5 mm thick) of a commercially available zirconium oxide ceramic (ZirCad) were sintered, sandblasted with aluminum oxide particles, and cleaned ultrasonically before bonding. The plates were randomly divided into five groups of 10. Three resin cements were selected (RelyX ARC, Multilink Automix, Clearfil SA Cement self-adhesive resin cement), along with two primers (Metal-Zirconia Primer, Alloy Primer) and one control group. The primers and resin cements were used according to manufacturers' recommendations. The control group comprised the conventional resin cement (RelyX ARC) without adhesive primer. Test cylinders (0.75 mm diameter × 1 mm high) were formed on zirconia surfaces by filling cylindrical Tygon tube molds with resin cement. The specimens were stored in distilled water for 24 hours at 37°C, then tested for shear strength on a Shimadzu EZ Test testing machine at 0.5 mm/min. Bond strength data were analyzed statistically by two-way ANOVA and Dunnett's test (5%). The bond strength means in MPa (± s.d.) were: RelyX ARC: 28.1 (6.6); Multilink Automix: 37.6 (4.5); Multilink Automix + Metal-Zirconia Primer: 55.7 (4.0); Clearfil SA Cement: 46.2 (3.3); and Clearfil SA Cement + Alloy Primer: 47.0 (4.1). Metal-Zirconia Primer increased the bond strength of Multilink Automix resin cement to zirconia, but no effect was observed for Alloy Primer using Clearfil SA Cement. RelyX ARC showed the lowest bond strength to zirconia. © 2015 by the American College of Prosthodontists.

Comparative evaluation of bonding strength of computer aided machined ceramic, pressable ceramic, and milled metal implant abutment copings and effect of surface conditioning on bonding strength: An in vitro study

PubMed Central

Rani, Sapna; Verma, Mahesh; Gill, Shubhra; Gupta, Rekha

2016-01-01

Background/Purpose: The aim of this study was to compare the shear bond strength of computer aided design/computer aided machined ceramic (CAD/CAM), pressable ceramic, and milled metal implant copings on abutment and the effect of surface conditioning on bonding strength. Materials and Methods: A total of 90 test samples were fabricated on three titanium abutments. Among 90 test samples, 30 copings were fabricated by CAD/CAM, 30 by pressable, and 30 by milling of titanium metal. These 30 test samples in each group were further subdivided equally for surface treatment. Fifteen out of 30 test samples in each group were surface conditioned with airborne particle abrasion. All the 90 test samples were luted on abutment with glass ionomer cement. Bonding strength was evaluated for all the samples using universal testing machine at a crosshead speed of 5 mm/min. The results obtained were compared and evaluated using one-way ANOVA with post-hoc and unpaired t-test at a significance level of 0.05. Results: The mean difference for CAD/CAM surface conditioned subgroup was 1.28 ± 0.12, for nonconditioned subgroup was 1.20 ± 0.11. The mean difference for pressable surface conditioned subgroup was 1.18 ± 0.04, and for nonconditioned subgroup was 0.75 ± 0.28. The mean difference for milled metal surface conditioned subgroup was 2.57 ± 0.58, and for nonconditioned subgroup was 1.49 ± 0.15. Conclusions: On comparison of bonding strength, milled metal copings had an edge over the other two materials, and surface conditioning increased the bond strength. PMID:27141163

Effect of endodontic chelating solutions on the bond strength of endodontic sealers.

PubMed

Tuncel, Behram; Nagas, Emre; Cehreli, Zafer; Uyanik, Ozgur; Vallittu, Pekka; Lassila, Lippo

2015-01-01

The purpose of this in vitro study was to evaluate the effect of various chelating solutions on the radicular push-out bond strength of calcium silicate-based and resin-based root canal sealers. Root canals of freshly-extracted single-rooted teeth (n = 80) were instrumented by using rotary instruments. The specimens were randomly divided into 4 groups according to the chelating solutions being tested: (1) 17% ethylenediaminetetraacetic acid (EDTA); (2) 9% etidronic acid; (3) 1% peracetic acid (PAA); and (4) distilled water (control). In each group, the roots were further assigned into 2 subgroups according to the sealer used: (1) an epoxy resin-based sealer (AH Plus) and (2) a calcium silicate-based sealer (iRoot SP). Four 1 mm-thick sections were obtained from the coronal aspect of each root (n = 40 slices/group). Push-out bond strength test was performed at a crosshead speed of 1 mm/min., and the bond strength data were analyzed statistically with two-way analysis of variance (ANOVA) with Bonferroni's post hoc test (p < 0.05). Failure modes were assessed quantitatively under a stereomicroscope. Irrespective of the irrigation regimens, iRoot SP exhibited significantly higher push-out bond strength values than AH Plus (p < 0.05). For both the sealers, the use of chelating solutions increased the bond strength, but to levels that were not significantly greater than their respective controls (p > 0.05). iRoot SP showed higher resistance to dislocation than AH Plus. Final irrigation with 17% EDTA, 9% Etidronic acid, and 1% PAA did not improve the bond strength of AH Plus and iRoot SP to radicular dentin.

Influence of tooth brushing on adhesion strength of orthodontic brackets bonded to porcelain.

PubMed

Durgesh, Bangalore H; Alhijji, Saleh; Hashem, Mohamed I; Al Kheraif, AbdulAziz A; Durgesh, Pavithra; Elsharawy, Mohamed; Vallittu, Pekka K

2016-09-28

Adhesive resin composite, which is used to bond orthodontic bracket to tooth surface is exposed to the influence of wear by tooth brushing and wear may influence loosening of the bracket. The aim of this study was to evaluate in vitro the effect of tooth brushing on the adhesion strength of orthodontic brackets bonded to surface treated porcelain. A total of 90 glazed porcelain fused to metal facets (PFM) were randomly assigned into 3 groups according to the surface treatment to be received. Group 1 was conditioned with hydrofluoric acid (HF), group 2 conditioned with grit-blasting (GB) and group 3 conditioned with tribochemical silica coating (RC). The groups were evaluated for surface roughness (Ra) before and after surface treatment. Next, 15 samples from each group were subjected to brushing and remaining 15 samples served as the baseline (n=15). Adhesion strength (shear bond strength)was recorded using a universal testing machine. Data collected were analyzed by ANOVA and Tukey's multiple comparison post hoc analysis. Tooth brushing decreased the bond strength in all groups. The highest adhesion strength (baseline and after brushing) was observed in group 3 (26.8 ± 1.77 MPa and 23.57 ± 1.02 MPa) and the lowest was found in group 1 (9.6 ± 1.5 MPa and 5.87 ± 0.77 MPa). Group 3 specimens exhibited the highest Ra (1.24 ± 0.08). It was found that tooth brushing of the exposed adhesive resin composite at the bracket-bonding substrate interface lowers the bonding strength regardless of the surface treatment of the substrate.

Evaluation of a thermoplastic polyimide (422) for bonding GR/PI composite

NASA Technical Reports Server (NTRS)

Progar, Donald J.

1988-01-01

A hot-melt processable copolyimide previously studied and characterized as an adhesive for bonding Ti-6Al-4V was used to bond Celion 6000/LARC-160 composite. Comparisons are made for the two adherend systems. A bonding cycle was determined for the composite bonding and lap shear specimens were prepared which were thermally exposed in a forced-air oven for up to 5000 h at 204 C. The lap shear strengths (LSSs) were determined at RT, 177, and 204 C. After thermal exposure at RT, 177, and 204 C the LSS decreased significantly; however, a slight increase was noted for the 204 C tests. Initially the LSS values are higher for the bonded Ti-6Al-4V than for the bonded composite, however, the LSS decreases dramatically between 5000 and 10,000 h of 204 C thermal exposure. Longer periods of thermal exposure up to 20,000 h results in further decreases in the LSSs. Although the bonded composite retained useful strengths for exposures up to 5000 h, based on the poor results of the bonded Ti-6Al-4V beyond 5000 h, the 422 adhesive bonded composites would most likely also produce poor strengths beyond 5000 h exposure. Adhesive bonded composite lap shear specimens exposed to boiling water for 72 h exhibited greatly reduced strengths at all test temperatures. The percent retained after water boil for each test temperature was essentially the same for both systems.

Evaluation of a thermoplastic polyimide (422) for bonding GR/PI composite

NASA Technical Reports Server (NTRS)

Progar, Donald J.

1988-01-01

A hot-melt processable copolyimide previously studied and characterized as an adhesive for bonding Ti-6Al-4V was used to bond Celion 6000/LARC-160 composite. Comparisons are made for the two adherend systems. A bonding cycle was determined for the composite bonding and lap shear specimens were prepared which were thermally exposed in a forced-air oven for up to 5000 h at 204 C. The lap shear strengths (LSSs) were determined at RT, 177, and 204 C. After thermal exposure at RT, 177, and 204 C the LSS decreased significantly; however, a slight increase was noted for the 204 C tests. Initially the LSS values are higher for the bonded Ti-6Al-4V than for the bonded composite, however, the LSS decreases dramatically between 5000 and 10,000 h of 204 C thermal exposure. Longer periods of thermal exposure up to 20,000 h results in further decreases in the LSSs. Although the bonded composite retained useful strengths for exposures up to 5000 h, based on the por results of the bonded Ti-6Al-4V beyond 5000 h, the 422 adhesive bonded composites would most likely also produce poor strengths beyond 5000 h exposure. Adhesive bonded composite lap shear specimens exposed to boiling water for 72 h exhibited greatly reduced strengths at all test temperatures. The percent retained after water boil for each test temperature was essentially the same for both systems.

[The adhesive properties of two bonding systems to tetracycline stained dentin].

PubMed

Liu, H L; Liang, K N; Cheng, L; Li, J Y; He, L B

2016-01-01

To investigate and compare the bonding properties of Single Bond 2 and SE Bond to tetracycline stained dentin in vitro. Ten extracted tetracycline stained human teeth and ten extracted normal human teeth were collected and the occlusal dentin surfaces of all extracted teeth were exposed. The tetracycline stained teeth and normal teeth were divided into two groups, respectively and randomly, based on the adhesives applied. Total-etch adhesive(Single Bond 2) and self-etch adhesive(SE Bond) were used. After application of the adhesives to the dentin surfaces, composite crowns were built up. After 24 h water storage, the teeth were sectioned longitudinally into sticks(0.9 mm×0.9 mm bonding area) for micro tensile testing or micro Raman spectroscopy detection. Bonding strength(μTBS) and resin conversion rate were analyzed using one-way ANOVA. The tetracycline Single Bond 2 group presented lower bonding strength[(16.17 ± 3.16) MPa] than the tetracycline SE Bond group[(25.82 ± 2.62) MPa], and also demonstrated lower bonding strength than the normal Single Bond 2 group[(29.13 ± 2.44) MPa] and the normal SE Bond group[(24.29±2.83) MPa] (P<0.05) , while there was no statistical differences among the other three groups(P>0.05). The resin conversion rate of tetracycline Single Bond 2 group[(55±6)%] was significantly lower than the tetracycline SE Bond group[(66±3)% ](P<0.05) and also lower than the normal Single Bond 2 group[(64 ± 5)%] and the normal SE Bond group[(65 ± 4)%] (P<0.05). No statistically significant differences were observed among the other three groups(P>0.05). The bonding strength of total-etch adhesive system to the tetracycline stained dentin was significantly lower than that to the normal dentin.

Influence of glass particle size of resin cements on bonding to glass ceramic: SEM and bond strength evaluation.

PubMed

Valentini, Fernanda; Moraes, Rafael R; Pereira-Cenci, Tatiana; Boscato, Noéli

2014-05-01

This study investigated the effect of the filler particle size (micron or submicron) of experimental resin cements on the microtensile bond strength to a glass-ceramic pretreated with hydrofluoric acid (HFA) etching or alumina airborne-particle abrasion (AA). Cements were obtained from a Bis-GMA/TEGDMA mixture filled with 60 mass% micron-sized (1 ± 0.2 µm) or submicron-sized (180 ± 30 µm) Ba-Si-Al glass particles. Ceramic blocks (PM9; VITA) were treated with 10% HFA for 60 s or AA for 15 s. Silane and adhesive were applied. Ceramic blocks were bonded to resin composite blocks (Z250; 3M ESPE) using one of the cements. Bonded specimens were sectioned into beams (n = 20/group) and subjected to microtensile bond strength tests. Data were analyzed using ANOVA and Student-Newman-Keuls' tests (5%). Failure modes were classified under magnification. Morphologies of the treated ceramic surfaces and bonded interfaces were evaluated by scanning electron microscopy. The HFA-submicron group had lower bond strengths than the other groups. All AA-submicron specimens debonded prematurely. Mixed failures were predominant for HFA groups, whereas interfacial failures predominated for AA groups. SEM revealed a honeycomb-like aspect in the HFA-treated ceramic, whereas the AA-treated groups showed an irregular retentive pattern. Continuity of cement infiltration along the bonded interface was more uniform for HFA-treated compared to AA-treated specimens. Cracks toward the bulk of the ceramic were observed in AA-treated specimens. Particle size significantly influenced the ceramic bond strength, whereas surface treatment had a minor effect. Copyright © 2014 Wiley Periodicals, Inc.

Effect of intrinsic wetness and regional difference on dentin bond strength.

PubMed

Pereira, P N; Okuda, M; Sano, H; Yoshikawa, T; Burrow, M F; Tagami, J

1999-01-01

The aim of this investigation was to determine the influence of intrinsic wetness on regional bond strengths of adhesive resins to dentin. Human caries-free third molars were randomly divided into three groups for bonding: Group 1--no pulpal pressure; Group 2--pulpal pressure of 15 cm H2O; and Group 3--dentin dried overnight in a desiccator. Clearfil Liner Bond II (Kuraray) or One Step (Bisco) adhesive resins systems were applied to the flat dentin surfaces and the teeth were restored with APX resin composite (Kuraray). After 24 h in water at 37 degrees C, the specimens were sectioned into 0.7 mm thick slabs and divided into three regional subgroups according to the remaining dentin thickness and visual criteria: pulp horn, center, and periphery. The slabs were then trimmed for the micro-tensile bond test and subjected to a tensile force and crosshead of 1 mm/min. The data were analyzed with ANOVA and Fisher's PLSD test at a confidence level of 95%. The fracture modes were determined under a scanning electron microscope (JXA-840, JEOL, Japan). No significant regional difference was observed for the Group 1 and 2 specimens restored with Clearfil Liner Bond II (p > 0.05). However, bond strengths significantly decreased at the pulp horn region of the Group 1 and 2 specimens restored with One Step (p > 0.01). All bond strengths of Group 3 decreased significantly and regional differences were not evident (p > 0.05). The dentin adhesive system should be chosen according to the substrate and region to be bonded, since bond strengths can vary according to the intrinsic wetness, region, and the adhesive system.

Effect of a New Surface Treatment Solution on the Bond Strength of Composite to Enamel

DTIC Science & Technology

2016-06-01

enamel ( Erickson et al., 2005). More significantly, clinical studies have shown significantly less marginal defects and staining with selective...using phosphoric acid. Erickson et al., (2009) also found improved bond strengths with a selective-etch step and attributed this to the degree of...cut enamel and dentin. Oper Dent 2005;30(1):39-49. Erickson RL, Barkmeier WW, Kimmes NS. Bond strength of self-etch adhesives to pre-etched

The effect of thermocycling on tensile bond strength of two soft liners.

PubMed

Geramipanah, Farideh; Ghandari, Masoumeh; Zeighami, Somayeh

2013-09-01

Failure of soft liners depends mostly on separation from the denture base resin; therefore measurement of the bond strength is very important. The purpose of this study was to compare the tensile bond strength of two soft liners (Acropars, Molloplast-B) to denture base resin before and after thermocycling. Twenty specimens fromeach of the two different soft liners were processed according to the manufacturer's instructions between two polymethyl methacrylate (PMMA) sheets. Ten specimens in each group were maintained in 37°C water for 24 hours and 10 were thermocycled (5000 cycles) among baths of 5° and 55°C. The tensile bond strength was measured using a universal testing machine at a crosshead speed of 5 mm/min. Mode of failure was determined with SEM (magnification ×30). Two-way ANOVA was used to analyze the data. The mean and standard deviation of tensile bond strength of Acropars and Molloplast-B before thermocycling were 6.59±1.85 and1.51±0.22 MPa, respectively and 5.89±1.52 and1.37±0.18 MPa, respectively after thermocycling. There was no significant difference before and after thermocycling. Mode of failure in Acropars and Molloplast-B were adhesive and cohesive, respectivley. The bond strength of Acropars was significantly higher than Molloplast-B (P<0.05).

Correlation among electronegativity, cation polarizability, optical basicity and single bond strength of simple oxides

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dimitrov, Vesselin, E-mail: vesselin@uctm.edu; Komatsu, Takayuki, E-mail: komatsu@mst.nagaokaut.ac.jp

2012-12-15

A suitable relationship between free-cation polarizability and electronegativity of elements in different valence states and with the most common coordination numbers has been searched on the basis of the similarity in physical nature of both quantities. In general, the cation polarizability increases with decreasing element electronegativity. A systematic periodic change in the polarizability against the electronegativity has been observed in the isoelectronic series. It has been found that generally the optical basicity increases and the single bond strength of simple oxides decreases with decreasing the electronegativity. The observed trends have been discussed on the basis of electron donation ability ofmore » the oxide ions and type of chemical bonding in simple oxides. - Graphical abstract: This figure shows the single bond strength of simple oxides as a function of element electronegativity. A remarkable correlation exists between these independently obtained quantities. High values of electronegativity correspond to high values of single bond strength and vice versa. It is obvious that the observed trend in this figure is closely related to the type of chemical bonding in corresponding oxide. Highlights: Black-Right-Pointing-Pointer A suitable relationship between free-cation polarizability and electronegativity of elements was searched. Black-Right-Pointing-Pointer The cation polarizability increases with decreasing element electronegativity. Black-Right-Pointing-Pointer The single bond strength of simple oxides decreases with decreasing the electronegativity. Black-Right-Pointing-Pointer The observed trends were discussed on the basis of type of chemical bonding in simple oxides.« less

Dentin-Composite Bond Strength Measurement Using the Brazilian Disk Test

PubMed Central

Carrera, Carola A.; Chen, Yung-Chung; Li, Yuping; Rudney, Joel; Aparicio, Conrado; Fok, Alex

2016-01-01

Objectives This study presents a variant of the Brazilian disk test (BDT) for assessing the bond strength between composite resins and dentin. Methods Dentin-composite disks (φ 5 mm × 2 mm) were prepared using either Z100 or Z250 (3M ESPE) in combination with one of three adhesives, Adper Easy Bond (EB), Adper Scotchbond Multi-Purpose (MP) and Adper Single Bond (SB), and tested under diametral compression. Acoustic emission (AE) and digital image correlation (DIC) were used to monitor debonding of the composite from the dentin ring. A finite element (FE) model was created to calculate the bond strengths using the failure loads. Fracture modes were examined by scanning electron microscopy (SEM). Results Most specimens fractured along the dentin-resin composite interface. DIC and AE confirmed interfacial debonding immediately before fracture of the dentin ring. Results showed that the mean bond strength with EB (14.9±1.9 MPa) was significantly higher than with MP (13.2±2.4 MPa) or SB (12.9±3.0 MPa) (p<0.05); no significant difference was found between MP and SB (p>0.05). Z100 (14.5±2.3 MPa) showed higher bond strength than Z250 (12.7±2.5 MPa) (p<0.05). Majority of specimens (91.3%) showed an adhesive failure mode. EB failed mostly at the dentin-adhesive interface, whereas MP at the composite-adhesive interface; specimens with SB failed at the composite-adhesive interface and cohesively in the adhesive. Conclusions The BDT variant showed to be a suitable alternative for measuring the bond strength between dentin and composite, with zero premature failure, reduced variability in the measurements, and consistent failure at the dentin-composite interface. PMID:27395367

A novel dentin bond strength measurement technique using a composite disk in diametral compression.

PubMed

Huang, Shih-Hao; Lin, Lian-Shan; Rudney, Joel; Jones, Rob; Aparicio, Conrado; Lin, Chun-Pin; Fok, Alex

2012-04-01

New methods are needed that can predict the clinical failure of dental restorations that primarily rely on dentin bonding. Existing methods have shortcomings, e.g. severe deviation in the actual stress distribution from theory and a large standard deviation in the measured bond strength. We introduce here a novel test specimen by examining an endodontic model for dentin bonding. Specifically, we evaluated the feasibility of using the modified Brazilian disk test to measure the post-dentin interfacial bond strength. Four groups of resin composite disks which contained a slice of dentin with or without an intracanal post in the center were tested under diametral compression until fracture. Advanced nondestructive examination and imaging techniques in the form of acoustic emission (AE) and digital image correlation (DIC) were used innovatively to capture the fracture process in real time. DIC showed strain concentration first appearing at one of the lateral sides of the post-dentin interface. The appearance of the interfacial strain concentration also coincided with the first AE signal detected. Utilizing both the experimental data and finite-element analysis, the bond/tensile strengths were calculated to be: 11.2 MPa (fiber posts), 12.9 MPa (metal posts), 8.9 MPa (direct resin fillings) and 82.6 MPa for dentin. We have thus established the feasibility of using the composite disk in diametral compression to measure the bond strength between intracanal posts and dentin. The new method has the advantages of simpler specimen preparation, no premature failure, more consistent failure mode and smaller variations in the calculated bond strength. Copyright © 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Effects of surface treatment and artificial aging on the shear bond strength of orthodontic brackets bonded to four different provisional restorations.

PubMed

Al Jabbari, Youssef S; Al Taweel, Sara M; Al Rifaiy, Mohammed; Alqahtani, Mohammed Q; Koutsoukis, Theodoros; Zinelis, Spiros

2014-07-01

To evaluate the combined effects of material type, surface treatment, and thermocycling on the bond strength of orthodontic brackets to materials used for the fabrication of provisional crowns. Four materials were included in this study (ProTemp, Trim Plus, Trim II, and Superpont C+B). Sixty cylindrical specimens (1 × 3 cm) were prepared from each material and equally divided into three groups. The first group was ground with silica carbide paper, the second was polished with pumice, and the last group was sandblasted with 50-µm aluminum oxide particles. Stainless-steel maxillary central incisor brackets (Victory Series, 3M) were bonded to the provisional material specimens with Transbond XT light-cured composite resin, and half of the specimens from each group were thermocycled 500 times in 5°C and 55°C water baths. Then the brackets were debonded with shear testing, and the results were statistically analyzed by three-way analysis of variance and Tukey's multiple-comparison tests at α  =  0.05. Adhesive Remnant Index (ARI) was also identified. Before and after thermocycling, ProTemp materials showed the highest shear bond strength with orthodontic brackets (10.3 and 13.1 MPa, respectively). The statistical analysis indicated an interaction among the three independent variables (P < .05) and statistically significant differences in bond strength among provisional materials (P < .001), surface treatments (P < .001), and thermocycling (P < .05). According to the ARI, most groups demonstrated adhesive failure. The provisional material type, surface treatment, and artificial aging have a significant effect on bond strength. Sandblasting treatment exerts a beneficial effect on shear bond strength.

Bond strength of universal adhesives: A systematic review and meta-analysis.

PubMed

Rosa, Wellington Luiz de Oliveira da; Piva, Evandro; Silva, Adriana Fernandes da

2015-07-01

A systematic review was conducted to determine whether the etch-and-rinse or self-etching mode is the best protocol for dentin and enamel adhesion by universal adhesives. This report followed the PRISMA Statement. A total of 10 articles were included in the meta-analysis. Two reviewers performed a literature search up to October 2014 in eight databases: PubMed, Web of Science, Scopus, BBO, SciELO, LILACS, IBECS and The Cochrane Library. In vitro studies evaluating the bond strength of universal adhesives to dentin and/or enamel by the etch-and-rinse and self-etch strategies were eligible to be selected. Statistical analyses were conducted using RevMan 5.1 (The Cochrane Collaboration, Copenhagen, Denmark). A global comparison was performed with random-effects models at a significance level of p<0.05. The analysis of dentin micro-tensile bond strength showed no statistically significant difference between the etch-and-rinse and self-etch strategies for mild universal adhesives (p≥0.05). However, for the ultra-mild All-Bond Universal adhesive, the etch-and-rinse strategy was significantly different than the self-etch mode in terms of dentin micro-tensile bond strength, as well as in the global analysis of enamel micro-tensile and micro-shear bond strength (p≤0.05). The enamel bond strength of universal adhesives is improved with prior phosphoric acid etching. However, this effect was not evident for dentin with the use of mild universal adhesives with the etch-and-rinse strategy. Selective enamel etching prior to the application of a mild universal adhesive is an advisable strategy for optimizing bonding. Copyright © 2015 Elsevier Ltd. All rights reserved.

The influence of four dual-cure resin cements and surface treatment selection to bond strength of fiber post

PubMed Central

Liu, Chang; Liu, Hong; Qian, Yue-Tong; Zhu, Song; Zhao, Su-Qian

2014-01-01

In this study, we evaluate the influence of post surface pre-treatments on the bond strength of four different cements to glass fiber posts. Eighty extracted human maxillary central incisors and canines were endodontically treated and standardized post spaces were prepared. Four post pre-treatments were tested: (i) no pre-treatment (NS, control), (ii) sandblasting (SA), (iii) silanization (SI) and (iv) sandblasting followed by silanization (SS). Per pre-treatment, four dual-cure resin cements were used for luting posts: DMG LUXACORE Smartmix Dual, Multilink Automix, RelyX Unicem and Panavia F2.0. All the specimens were subjected to micro push-out test. Two-way analysis of variance and Tukey post hoc tests were performed (α=0.05) to analyze the data. Bond strength was significantly affected by the type of resin cement, and bond strengths of RelyX Unicem and Panavia F2.0 to the fiber posts were significantly higher than the other cement groups. Sandblasting significantly increased the bond strength of DMG group to the fiber posts. PMID:24177170

Influence of the Conditioning Method for Pre-Sintered Zirconia on the Shear Bond Strength of Bilayered Porcelain/Zirconia

PubMed Central

Spintzyk, Sebastian; Yamaguchi, Kikue; Sawada, Tomofumi; Schille, Christine; Schweizer, Ernst; Ozeki, Masahiko; Geis-Gerstorfer, Jürgen

2016-01-01

This study evaluated the bond strength of veneering porcelain with an experimental conditioner-coated zirconia. Pre-sintered Y-TZP specimens (n = 44) were divided in two groups based on conditioning type. After sintering, all sample surfaces were sandblasted and layered with veneering porcelain. Additionally, half of the specimens in each group underwent thermal cycling (10,000 cycles, 5–55 °C), and all shear bond strengths were measured. After testing, the failure mode of each fractured specimen was determined. Differences were tested by parametric and Fisher’s exact tests (α = 0.05). The differences in bond strength were not statistically significant. Adhesive fractures were dominantly observed for the non-thermal cycled specimens. After thermal cycling, the conditioner-coated group showed cohesive and mixed fractures (p = 0.0021), whereas the uncoated group showed more adhesive fractures (p = 0.0021). Conditioning of the pre-sintered Y-TZP did not change the shear bond strength of the veneering porcelain, but did improve the failure mode after thermal cycling. PMID:28773885

Comparison of micro push-out bond strengths of two fiber posts luted using simplified adhesive approaches.

PubMed

Mumcu, Emre; Erdemir, Ugur; Topcu, Fulya Toksoy

2010-05-01

By means of a micro push-out test, this study compared the bond strengths of two types of fiber-reinforced posts cemented with luting cements based on two currently available adhesive approaches as well as evaluated their failure modes. Sixty extracted single-rooted human maxillary central incisor and canine teeth were sectioned below the cementoenamel junction, and the roots were endodontically treated. Following standardized post space preparation, the roots were divided into two fiber post groups and then further into three subgroups of 10 specimens each according to the luting cements. A push-out test was performed to measure regional bond strengths, and the fracture modes were evaluated using a stereomicroscope. At the root section, there were no statistically significant differences (p>0.05) in push-out bond strength among the tested luting cements. Nevertheless, the push-out bond strength values of glass fiber-reinforced posts were higher than those of carbon fiber-reinforced posts, irrespective of the adhesive approach used. On failure mode, the predominant failure mode was adhesive failure between dentin and the luting cement.

Effect of different surface treatments on shear bond strength of zirconia to three resin cements

NASA Astrophysics Data System (ADS)

Dadjoo, Nisa

Statement of problem: There are no standard guidelines for material selection to obtain acceptable bonding to high-strength zirconium oxide ceramic. Studies suggest resin cements in combination with MDP-containing primer is a reasonable choice, however, the other cements cannot be rejected and need further investigation. Objective: The purpose of this in vitro study was the evaluation of the shear bond strength of three composite resin cements to zirconia ceramic after using different surface conditioning methods. Materials and methods: One hundred and twenty sintered Y-TZP ceramic (IPS e.max ZirCAD) squares (8 x 8 x 4 mm) were embedded in acrylic molds, then divided into three groups (n=40) based on the type of cement used. Within each group, the specimens were divided into four subgroups (n=10) and treated as follows: (1) Air abrasion with 50microm aluminum oxide (Al2O 3) particles (ALO); (2) Air abrasion + Scotchbond Universal adhesive (SBU); (3) Air abrasion + Monobond Plus (MBP); (4) Air abrasion + Z-Prime Plus (ZPP). Composite cylinders were used as carriers to bond to conditioned ceramic using (1) RelyX Ultimate adhesive resin cement (RX); (2) Panavia SA self-adhesive resin cement (PSA); (3) Calibra esthetic cement (CAL). The bonded specimens were submerged in distilled water and subjected to 24-hour incubation period at 37°C. All specimens were stressed in shear at a constant crosshead speed of 0.5 mm/min until failure. Statistical analysis was performed by ANOVA. The bond strength values (MPa), means and standard deviations were calculated and data were analyzed using analysis of variance with Fisher's PLSD multiple comparison test at the 0.05 level of significance. The nature of failure was recorded. Results: The two-way ANOVA showed Panavia SA to have the highest strength at 44.3 +/- 16.9 MPa (p<0.05). The combination of Scotchbond Universal surface treatment with Panavia SA cement showed statistically higher bond strength (p=0.0054). The highest bond strengths for all three cements were observed with Scotchbond Universal surface treatment (p=0.0041). Calibra in combination with aluminum oxide air abrasion resulted in statistically lowest bond strength at 12.0 +/- 3.9 MPa. The predominant mode of failure was cohesive with cement remaining principally on the zirconium oxide samples in 57.5% of the specimens, followed by cement found on both the zirconium oxide samples and composite rods (mixed) in 32.5% of the samples. Only 10% of the specimens were found with cement on the composite rods (adhesive failure). Conclusions: Within the limitations of this in vitro study, the MDP-containing resin cement, Panavia SA, yielded the strongest bond to Y-TZP ceramic when compared to adhesive (RelyX Ultimate) or esthetic (Calibra) resin cements. Air abrasion particle + Scotchbond Universal surface treatment demonstrated the highest bond strength regardless of the cement. Significance: The variation of surface conditioning methods yielded different results in accordance with the cement types. Overall, Scotchbond Universal adhesive + air abrasion yielded the highest bond strengths among all three surface treatments. The phosphate monomer-containing luting system, Panavia SA, is acceptable for bonding to zirconia ceramics.

Effect of surface condition of dental zirconia ceramic (Denzir) on bonding.

PubMed

Uo, Motohiro; Sjögren, Göran; Sundh, Anders; Goto, Mitsunari; Watari, Fumio; Bergman, Maud

2006-09-01

Yttria partially stabilized zirconia (YPSZ) ceramics are suitable for dental and medical use because of their high fracture toughness and chemical durability. The purpose of this study was to examine the bonding behavior of a dental YPSZ ceramic, Denzir. After being subjected to various surface treatments, Denzir specimens were bonded to each other using an adhesive resin composite, glass ionomer, or zinc phosphate cement. Bonding strength was then determined by the shearing test. No significant differences (p>0.05) were observed between SiC- and Al2O3-blasted specimens. In all surface treatments, the shear bond strength significantly (p<0.05) increased in the order of adhesive resin composite cement > glass ionomer cement > zinc phosphate cement. Moreover, silanization with methacryloxy propyl trimethoxysilane slightly increased the bonding strength of the adhesive resin composite cement.

Bond Strength Mechanism of Fly Ash Based Geopolymer Mortars: A Review

NASA Astrophysics Data System (ADS)

Zailani, W. W. A.; Abdullah, M. M. A. B.; Razak, R. A.; Zainol, M. R. R. M. A.; Tahir, M. F. M.

2017-11-01

Geopolymer possess many excellent properties such as high compressive and bond strength, long term durability, better acid resistance and also known as a “Sustainable Material” due to its low carbon emission and low energy consumption. Thus, it is a good opportunity to develop and explore not only for cement and concrete but also as geopolymeric repair materials. This reviews showed that good bonding properties between geopolymeric repair material and concrete substrate is important in order to acquire an enhanced resistance against penetration of harmful substances and avoiding respalling of the repair material by understanding the bonding behaviour. Bond strength depends to the properties of the repair materials itself and also the surface preparations of concrete substrate.

Improved Bond Equations for Fiber-Reinforced Polymer Bars in Concrete.

PubMed

Pour, Sadaf Moallemi; Alam, M Shahria; Milani, Abbas S

2016-08-30

This paper explores a set of new equations to predict the bond strength between fiber reinforced polymer (FRP) rebar and concrete. The proposed equations are based on a comprehensive statistical analysis and existing experimental results in the literature. Namely, the most effective parameters on bond behavior of FRP concrete were first identified by applying a factorial analysis on a part of the available database. Then the database that contains 250 pullout tests were divided into four groups based on the concrete compressive strength and the rebar surface. Afterward, nonlinear regression analysis was performed for each study group in order to determine the bond equations. The results show that the proposed equations can predict bond strengths more accurately compared to the other previously reported models.

A comparative study of shear bond strength of orthodontic bracket after acid-etched and Er:YAG treatment on enamel surface

NASA Astrophysics Data System (ADS)

Leão, Juliana C.; Mota, Cláudia C. B. O.; Cassimiro-silva, Patricia F.; Gomes, Anderson S. L.

2016-02-01

This study aimed to evaluate the shear bond strength (SBS) of teeth prepared for orthodontic bracket bonding with 37% phosphoric acid and Er:YAG laser. Forty bovine incisors were divided into two groups. In Group I, the teeth were conditioned with 37% phosphoric acid and brackets were bonded with Transbond XT; in Group II, the teeth were irradiated with Er:YAG and bonding with Transbond XT. After SBS test, the adhesive remnant index was determined. Adhesion to dental hard tissues after Er:YAG laser etching was inferior to that obtained after acid etching but exceeded what is believed to be clinically sufficient strength, and therefore can be used in patients.