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Sample records for implant surface technology

  1. Advancing dental implant surface technology--from micron- to nanotopography.

    PubMed

    Mendonça, Gustavo; Mendonça, Daniela B S; Aragão, Francisco J L; Cooper, Lyndon F

    2008-10-01

    Current trends in clinical dental implant therapy include use of endosseous dental implant surfaces embellished with nanoscale topographies. The goal of this review is to consider the role of nanoscale topographic modification of titanium substrates for the purpose of improving osseointegration. Nanotechnology offers engineers and biologists new ways of interacting with relevant biological processes. Moreover, nanotechnology has provided means of understanding and achieving cell specific functions. The various techniques that can impart nanoscale topographic features to titanium endosseous implants are described. Existing data supporting the role of nanotopography suggest that critical steps in osseointegration can be modulated by nanoscale modification of the implant surface. Important distinctions between nanoscale and micron-scale modification of the implant surface are presently considered. The advantages and disadvantages of nanoscale modification of the dental implant surface are discussed. Finally, available data concerning the current dental implant surfaces that utilize nanotopography in clinical dentistry are described. Nanoscale modification of titanium endosseous implant surfaces can alter cellular and tissue responses that may benefit osseointegration and dental implant therapy.

  2. Surface characterization and biocompatibility of titanium alloys implanted with nitrogen by Hardion+ technology.

    PubMed

    Gordin, D M; Gloriant, T; Chane-Pane, V; Busardo, D; Mitran, V; Höche, D; Vasilescu, C; Drob, S I; Cimpean, A

    2012-12-01

    In this study, the new Hardion+ micro-implanter technology was used to modify surface properties of biomedical pure titanium (CP-Ti) and Ti-6Al-4V ELI alloy by implantation of nitrogen ions. This process is based on the use of an electron cyclotron resonance ion source to produce a multienergetic ion beam from multicharged ions. After implantation, surface analysis methods revealed the formation of titanium nitride (TiN) on the substrate surfaces. An increase in superficial hardness and a significant reduction of friction coefficient were observed for both materials when compared to non-implanted samples. Better corrosion resistance and a significant decrease in ion release rates were observed for N-implanted biomaterials due to the formation of the protective TiN layer on their surfaces. In vitro tests performed on human fetal osteoblasts indicated that the cytocompatibility of N-implanted CP-Ti and Ti-6Al-4V alloy was enhanced in comparison to that of the corresponding non treated samples. Consequently, Hardion+ implantation technique can provide titanium alloys with better qualities in terms of corrosion resistance, cell proliferation, adhesion and viability.

  3. Ion beam technology applications study. [ion impact, implantation, and surface finishing

    NASA Technical Reports Server (NTRS)

    Sellen, J. M., Jr.; Zafran, S.; Komatsu, G. K.

    1978-01-01

    Specific perceptions and possible ion beam technology applications were obtained as a result of a literature search and contact interviews with various institutions and individuals which took place over a 5-month period. The use of broad beam electron bombardment ion sources is assessed for materials deposition, removal, and alteration. Special techniques examined include: (1) cleaning, cutting, and texturing for surface treatment; (2) crosslinking of polymers, stress relief in deposited layers, and the creation of defect states in crystalline material by ion impact; and (3) ion implantation during epitaxial growth and the deposition of neutral materials sputtered by the ion beam. The aspects, advantages, and disadvantages of ion beam technology and the competitive role of alternative technologies are discussed.

  4. Biocompatible implant surface treatments.

    PubMed

    Pattanaik, Bikash; Pawar, Sudhir; Pattanaik, Seema

    2012-01-01

    Surface plays a crucial role in biological interactions. Surface treatments have been applied to metallic biomaterials in order to improve their wear properties, corrosion resistance, and biocompatibility. A systematic review was performed on studies investigating the effects of implant surface treatments on biocompatibility. We searched the literature using PubMed, electronic databases from 1990 to 2009. Key words such as implant surface topography, surface roughness, surface treatment, surface characteristics, and surface coatings were used. The search was restricted to English language articles published from 1990 to December 2009. Additionally, a manual search in the major dental implant journals was performed. When considering studies, clinical studies were preferred followed by histological human studies, animal studies, and in vitro studies. A total of 115 articles were selected after elimination: clinical studies, 24; human histomorphometric studies, 11; animal histomorphometric studies, 46; in vitro studies, 34. The following observations were made in this review: · The focus has shifted from surface roughness to surface chemistry and a combination of chemical manipulations on the porous structure. More investigations are done regarding surface coatings. · Bone response to almost all the surface treatments was favorable. · Future trend is focused on the development of osteogenic implant surfaces. Limitation of this study is that we tried to give a broader overview related to implant surface treatments. It does not give any conclusion regarding the best biocompatible implant surface treatment investigated till date. Unfortunately, the eventually selected studies were too heterogeneous for inference of data.

  5. Anodized dental implant surface.

    PubMed

    Mishra, Sunil Kumar; Kumar, Muktadar Anand; Chowdhary, Ramesh

    2017-01-01

    Anodized implants with moderately rough surface were introduced around 2000. Whether these implants enhanced biologic effect to improve the environment for better osseointegration was unclear. The purpose of this article was to review the literature available on anodized surface in terms of their clinical success rate and bone response in patients till now. A broad electronic search of MEDLINE and PubMed databases was performed. A focus was made on peer-reviewed dental journals. Only articles related to anodized implants were included. Both animal and human studies were included. The initial search of articles resulted in 581 articles on anodized implants. The initial screening of titles and abstracts resulted in 112 full-text papers; 40 animal studies, 16 studies on cell adhesion and bacterial adhesion onto anodized surfaced implants, and 47 human studies were included. Nine studies, which do not fulfill the inclusion criteria, were excluded. The long-term studies on anodized surface implants do favor the surface, but in most of the studies, anodized surface is compared with that of machined surface, but not with other surfaces commercially available. Anodized surface in terms of clinical success rate in cases of compromised bone and immediately extracted sockets has shown favorable success.

  6. Nanostructured surfaces of dental implants.

    PubMed

    Bressan, Eriberto; Sbricoli, Luca; Guazzo, Riccardo; Tocco, Ilaria; Roman, Marco; Vindigni, Vincenzo; Stellini, Edoardo; Gardin, Chiara; Ferroni, Letizia; Sivolella, Stefano; Zavan, Barbara

    2013-01-17

    The structural and functional fusion of the surface of the dental implant with the surrounding bone (osseointegration) is crucial for the short and long term outcome of the device. In recent years, the enhancement of bone formation at the bone-implant interface has been achieved through the modulation of osteoblasts adhesion and spreading, induced by structural modifications of the implant surface, particularly at the nanoscale level. In this context, traditional chemical and physical processes find new applications to achieve the best dental implant technology. This review provides an overview of the most common manufacture techniques and the related cells-surface interactions and modulation. A Medline and a hand search were conducted to identify studies concerning nanostructuration of implant surface and their related biological interaction. In this paper, we stressed the importance of the modifications on dental implant surfaces at the nanometric level. Nowadays, there is still little evidence of the long-term benefits of nanofeatures, as the promising results achieved in vitro and in animals have still to be confirmed in humans. However, the increasing interest in nanotechnology is undoubted and more research is going to be published in the coming years.

  7. JPRS Report. Science & Technology, Japan. Surface Reforming by Ion Implantation Symposium.

    DTIC Science & Technology

    2007-11-02

    trains. In research into nuclear fusion aimed at developing energy for the next age , technology for generating a great quantity of ion beams to meet...metal membrane, increasing its adhesive strength through ion implantation and brazing and soldering it with the metal bulk via the metal membrane. 39...100-nm Fe and soldering it with a cast iron plate using a Pb- Sn soft solder21. The interfacial adhesive strength between Ti and Si3N4 increases as

  8. Microsystems Technology for Retinal Implants

    NASA Astrophysics Data System (ADS)

    Weiland, James

    2005-03-01

    The retinal prosthesis is targeted to treat age-related macular degeneration, retinitis pigmentosa, and other outer retinal degenerations. Simulations of artificial vision have predicted that 600-1000 individual pixels will be needed if a retinal prosthesis is to restore function such as reading large print and face recognition. An implantable device with this many electrode contacts will require microsystems technology as part of its design. An implantable retinal prosthesis will consist of several subsystems including an electrode array and hermetic packaging. Microsystems and microtechnology approaches are being investigated as possible solutions for these design problems. Flexible polydimethylsiloxane (PDMS) substrate electrode arrays and silicon micromachined electrode arrays are under development. Inactive PDMS electrodes have been implanted in 3 dogs to assess mechanical biocompatibility. 3 dogs were followed for 6 months. The implanted was securely fastened to the retina with a single retinal tack. No post-operative complications were evident. The array remained within 100 microns of the retinal surface. Histological evaluation showed a well preserved retina underneath the electrode array. A silicon device with electrodes suspended on micromachined springs has been implanted in 4 dogs (2 acute implants, 2 chronic implants). The device, though large, could be inserted into the eye and positioned on the retina. Histological analysis of the retina from the spring electrode implants showed that spring mounted posts penetrated the retina, thus the device will be redesigned to reduce the strength of the springs. These initial implants will provide information for the designers to make the next generation silicon device. We conclude that microsystems technology has the potential to make possible a retinal prosthesis with 1000 individual contacts in close proximity to the retina.

  9. [Comperative study of implant surface characteristics].

    PubMed

    Katona, Bernadett; Daróczi, Lajos; Jenei, Attila; Bakó, József; Hegedus, Csaba

    2013-12-01

    The osseointegration between the implant and its' bone environment is very important. The implants shall meet the following requirements: biocompatibility, rigidity, resistance against corrosion and technical producibility. In our present study surface morphology and material characteristics of different implants (Denti Bone Level, Denti Zirconium C, Bionika CorticaL, Straumann SLA, Straumann SLA Active, Dentsply Ankylos and Biotech Kontact implant) were investigated with scanning electron microscopy and energy-dispersive X-ray spectroscopy. The possible surface alterations caused by the manufacturing technology were also investigated. During grit-blasting the implants' surface is blasted with hard ceramic particles (titanium oxide, alumina, calcium phosphate). Properties of blasting material are critical because the osseointegration of dental implants should not be hampered. The physical and chemical features of blasting particles could importantly affect the produced surfaces of implants. Titanium surfaces with micro pits are created after immersion in mixtures of strong acids. On surfaces after dual acid-etching procedures the crosslinking between fibrin and osteogenetic cells could be enhanced therefore bone formation could be directly facilitated on the surface of the implant. Nowadays there are a number of surface modification techniques available. These can be used as a single method or in combination with each other. The effect of the two most commonly used surface modifications (acid-etching and grit-blasting) on different implants are demonstrated in our investigation.

  10. The combination of digital surface scanners and cone beam computed tomography technology for guided implant surgery using 3Shape implant studio software: a case history report.

    PubMed

    Lanis, Alejandro; Álvarez Del Canto, Orlando

    2015-01-01

    The incorporation of virtual engineering into dentistry and the digitization of information are providing new perspectives and innovative alternatives for dental treatment modalities. The use of digital surface scanners with surgical planning software allows for the combination of the radiographic, prosthetic, surgical, and laboratory fields under a common virtual scenario, permitting complete digital treatment planning. In this article, the authors present a clinical case in which a guided implant surgery was performed based on a complete digital surgical plan combining the information from a cone beam computed tomography scan and the virtual simulation obtained from the 3Shape TRIOS intraoral surface scanner. The information was imported to and combined in the 3Shape Implant Studio software for guided implant surgery planning. A surgical guide was obtained by a 3D printer, and the surgical procedure was done using the Biohorizons Guided Surgery Kit and its protocol.

  11. Advances in lens implant technology

    PubMed Central

    Kampik, Anselm; Dexl, Alois K.; Zimmermann, Nicole; Glasser, Adrian; Baumeister, Martin; Kohnen, Thomas

    2013-01-01

    Cataract surgery is one of the oldest and the most frequent outpatient clinic operations in medicine performed worldwide. The clouded human crystalline lens is replaced by an artificial intraocular lens implanted into the capsular bag. During the last six decades, cataract surgery has undergone rapid development from a traumatic, manual surgical procedure with implantation of a simple lens to a minimally invasive intervention increasingly assisted by high technology and a broad variety of implants customized for each patient’s individual requirements. This review discusses the major advances in this field and focuses on the main challenge remaining – the treatment of presbyopia. The demand for correction of presbyopia is increasing, reflecting the global growth of the ageing population. Pearls and pitfalls of currently applied methods to correct presbyopia and different approaches under investigation, both in lens implant technology and in surgical technology, are discussed. PMID:23413369

  12. Formation technology of flat surface with epitaxial growth on ion-implanted (100)-oriented Si surface of thin silicon-on-insulator

    NASA Astrophysics Data System (ADS)

    Furukawa, Kiichi; Teramoto, Akinobu; Kuroda, Rihito; Suwa, Tomoyuki; Hashimoto, Keiichi; Sugawa, Shigetoshi; Suzuki, Daisuke; Chiba, Yoichiro; Ishii, Katsutoshi; Shimizu, Akira; Hasebe, Kazuhide

    2017-10-01

    For the development of three-dimensional devices, selective epitaxial growth (SEG) technology has attracted much attention. SEG has been applied to fabricate many devices and it is expected to be used in future manufacturing processes. Therefore, its characteristics must be examined in detail to extend its application. For the fabrication of a three-dimensional device structure, the selectivity of epitaxial growth must be accurately controlled not only on Si and SiO2, but also on different impurity-type silicon surfaces. In this work, we investigated some characteristics of the SEG process, especially focusing on the surface roughness after SEG. Both vapor phase epitaxy (VPE) and solid phase epitaxy (SPE) were performed on ion-implanted silicon-on-insulator (SOI) thin wafers. It was often reported that epitaxial growth is very sensitive to the crystal condition of the substrate on which the films are deposited. However, we first revealed that the impurity type (p- or n-type) and its concentration at the substrate surface markedly changed the roughness and incubation times of the deposition. From our results, SPE with the oxide cap layer formation is effective for maintaining almost the same flatness as the original wafer surface. It is also effective to employ the low-temperature H2/Xe plasma treatment after the SEG to reduce roughness.

  13. SURFACE CHEMISTRY INFLUENCE IMPLANT BIOCOMPATIBILITY

    PubMed Central

    Thevenot, Paul; Hu, Wenjing; Tang, Liping

    2011-01-01

    Implantable medical devices are increasingly important in the practice of modern medicine. Unfortunately, almost all medical devices suffer to a different extent from adverse reactions, including inflammation, fibrosis, thrombosis and infection. To improve the safety and function of many types of medical implants, a major need exists for development of materials that evoked desired tissue responses. Because implant-associated protein adsorption and conformational changes thereafter have been shown to promote immune reactions, rigorous research efforts have been emphasized on the engineering of surface property (physical and chemical characteristics) to reduce protein adsorption and cell interactions and subsequently improve implant biocompatibility. This brief review is aimed to summarize the past efforts and our recent knowledge about the influence of surface functionality on protein:cell:biomaterial interactions. It is our belief that detailed understandings of bioactivity of surface functionality provide an easy, economic, and specific approach for the future rational design of implantable medical devices with desired tissue reactivity and, hopefully, wound healing capability. PMID:18393890

  14. Tribological performance of surfaces enhanced by texturing and nitrogen implantation

    NASA Astrophysics Data System (ADS)

    Liu, Derong; Zhang, Qi; Qin, Zhenbo; Luo, Qin; Wu, Zhong; Liu, Lei

    2016-02-01

    In this paper, a novel texturing technology by means of electrodepositon is introduced. Textured surface covered with small bumps with the average size of 28 μm in diameter and 10 μm in height was fabricated. The trough around the bumps acts as the pocket to trap the debris. The nitrogen implantation was used to enhance the tribological properties of textured surfaces. The effects of implanted energy and dose on the structures of coating and tribological performances of textured surfaces were studied. The results show that the formation of Cr2N or CrN depends on the implanted dose. After nitrogen ion implantation, the friction coefficient of textured surface reduced and the wear resistance of textured surface was improved. The wear resistance enhances with increase of implanted dose, and has little to do with implanted energy.

  15. Implant surfaces and interface processes.

    PubMed

    Kasemo, B; Gold, J

    1999-06-01

    The past decades and current R&D of biomaterials and medical implants show some general trends. One major trend is an increased degree of functionalization of the material surface, better to meet the demands of the biological host system. While the biomaterials of the past and those in current use are essentially bulk materials (metals, ceramics, polymers) or special compounds (bioglasses), possibly with some additional coating (e.g., hydroxyapatite), the current R&D on surface modifications points toward much more complex and multifunctional surfaces for the future. Such surface modifications can be divided into three classes, one aiming toward an optimized three-dimensional physical microarchitecture of the surface (pore size distributions, "roughness", etc.), the second one focusing on the (bio) chemical properties of surface coatings and impregnations (ion release, multi-layer coatings, coatings with biomolecules, controlled drug release, etc.), and the third one dealing with the viscoelastic properties (or more generally the micromechanical properties) of material surfaces. These properties are expected to affect the interfacial processes cooperatively, i.e., there are likely synergistic effects between and among them: The surface is "recognized" by the biological system through the combined chemical and topographic pattern of the surface, and the viscoelastic properties. In this presentation, the development indicated above is discussed briefly, and current R&D in this area is illustrated with a number of examples from our own research. The latter include micro- and nanofabrication of surface patterns and topographies by the use of laser machining, photolithographic techniques, and electron beam and colloidal lithographies to produce controlled structures on implant surfaces in the size range 10 nm to 100 microns. Examples of biochemical modifications include mono- or lipid membranes and protein coatings on different surfaces. A new method to evaluate, e

  16. Using Aerospace Technology To Design Orthopedic Implants

    NASA Technical Reports Server (NTRS)

    Saravanos, D. A.; Mraz, P. J.; Davy, D. T.

    1996-01-01

    Technology originally developed to optimize designs of composite-material aerospace structural components used to develop method for optimizing designs of orthopedic implants. Development effort focused on designing knee implants, long-term goal to develop method for optimizing designs of orthopedic implants in general.

  17. Using Aerospace Technology To Design Orthopedic Implants

    NASA Technical Reports Server (NTRS)

    Saravanos, D. A.; Mraz, P. J.; Davy, D. T.

    1996-01-01

    Technology originally developed to optimize designs of composite-material aerospace structural components used to develop method for optimizing designs of orthopedic implants. Development effort focused on designing knee implants, long-term goal to develop method for optimizing designs of orthopedic implants in general.

  18. Ion Implanted Gaas Integrated Optics Fabrication Technology

    NASA Astrophysics Data System (ADS)

    Mentzer, M. A.; Hunsperger, R. G.; Bartko, J.; Zavada, J. M.; Jenkinson, H. A.

    1985-01-01

    Ion implantation of semiconductor materials is a fabrication technique that offers a number of distinct advantages for the formation of guided-wave components and microelectronic devices. Implanted damage and dopants produce optical and electronic changes that can be utilized for sensing and signal processing applications. GaAs is a very attractive material for optical fabrication since it is transparent out to the far infrared. It can be used to fabricate optical waveguides, directional couplers, EO modulators, and detectors, as well as other guided wave structures. The presence of free carriers in GaAs lowers the refractive index from that of the pure semiconductor material. This depression of the refractive index is primarily due to the negative contribution of the free carrier plasma to the dielectric constant of the semiconductor. Bombardment of n-type GaAs by protons creates damage sites near the surface of the crystal structure where free carriers are trapped. This "free carrier compensated" region in the GaAs has a higher refractive index than the bulk region. If the compensated region is sufficiently thick and has a refractive index which is sufficiently larger than that of the bulk n-type region, an optical waveguide is formed. In this paper, a description of ion implantation techniques for the fabrication of both planar and channel integrated optical structures in GaAs is presented, and is related to the selection of ion species, implant energy and fluence, and to the physical processes involved. Lithographic technology and masking techniques are discussed for achieving a particular desired implant profile. Finally, the results of a set of ion implantation experiments are presented.

  19. Visualization of Medpor implants using surface rendering.

    PubMed

    Wang, Meng; Gui, Lai; Liu, Xiao-Jing

    2011-09-01

    The Medpor surgical implant is one of the easiest implants in clinical practice, especially in craniomaxillofacial surgery. It is often used as a bone substitute material for the repair of skull defects and facial deformities. The Medpor implant has several advantages but its use is limited because it is radiolucent in both direct radiography and conventional computed tomography, causing serious problems with visualization. In this study, a new technique for visualizing Medpor implants was evaluated in 10 patients who had undergone facial reconstruction using the material. Continuous volume scans were made using a 16-channel tomographic scanner and 3D reconstruction software was used to create surface renderings. The threshold values for surface renderings of the implant ranged from -70 HU to -20 HU, with bone as the default. The shape of the implants and the spatial relationship between bone and implant could both be displayed. Surface rendering can allow successful visualization of Medpor implants in the body.

  20. Tapered Implants in Dentistry: Revitalizing Concepts with Technology: A Review.

    PubMed

    Wilson, T G; Miller, R J; Trushkowsky, R; Dard, M

    2016-03-01

    The most common approach to lessen treatment times is by decreasing the healing period during which osseointegration is established. Implant design parameters such as implant surface, primary stability, thread configuration, body shape, and the type of bone have to be considered to obtain this objective. The relationship that exists between these components will define the initial stability of the implant. It is believed implant sites using a tapered design and surface modification can increase the primary stability in low-density bone. Furthermore, recent experimental preclinical work has shown the possibility of attaining primary stability of immediately loaded, tapered dental implants without compromising healing and rapid bone formation while minimizing the implant stability loss at compression sites. This may be of singular importance with immediate/early functional loading of single implants placed in poor-quality bone. The selection of an implant that will provide adequate stability in bone of poor quality is important. A tapered-screw implant design will provide adequate stability because it creates pressure on cortical bone in areas of reduced bone quality. Building on the success of traditional tapered implant therapy, newer tapered implant designs should aim to maximize the clinical outcome by implementing new technologies with adapted clinical workflows. © International & American Associations for Dental Research 2016.

  1. Antimicrobial technology in orthopedic and spinal implants

    PubMed Central

    Eltorai, Adam EM; Haglin, Jack; Perera, Sudheesha; Brea, Bielinsky A; Ruttiman, Roy; Garcia, Dioscaris R; Born, Christopher T; Daniels, Alan H

    2016-01-01

    Infections can hinder orthopedic implant function and retention. Current implant-based antimicrobial strategies largely utilize coating-based approaches in order to reduce biofilm formation and bacterial adhesion. Several emerging antimicrobial technologies that integrate a multidisciplinary combination of drug delivery systems, material science, immunology, and polymer chemistry are in development and early clinical use. This review outlines orthopedic implant antimicrobial technology, its current applications and supporting evidence, and clinically promising future directions. PMID:27335811

  2. Antimicrobial technology in orthopedic and spinal implants.

    PubMed

    Eltorai, Adam Em; Haglin, Jack; Perera, Sudheesha; Brea, Bielinsky A; Ruttiman, Roy; Garcia, Dioscaris R; Born, Christopher T; Daniels, Alan H

    2016-06-18

    Infections can hinder orthopedic implant function and retention. Current implant-based antimicrobial strategies largely utilize coating-based approaches in order to reduce biofilm formation and bacterial adhesion. Several emerging antimicrobial technologies that integrate a multidisciplinary combination of drug delivery systems, material science, immunology, and polymer chemistry are in development and early clinical use. This review outlines orthopedic implant antimicrobial technology, its current applications and supporting evidence, and clinically promising future directions.

  3. Creation of wear-resistant near-surface-layers with inhomogeneous structure on NiTi alloy by ion implantation technology

    NASA Astrophysics Data System (ADS)

    Swiatek, Z.; Levintant-Zayonts, N.; Michalec, M.; Czeppe, T.; Lipinski, M.; Bonchyk, O.; Savitskij, G.

    In the present study we report the changes in the modified near-surface layer on NiTi shape memory alloy, caused by ion implantation as well as their influence on the structure and mechanical properties of this material. Experimental results of an inhomogeneous structure and tribological properties of implanted NiTi are discussed in this paper.

  4. Energy conservation potential of surface modification technologies

    SciTech Connect

    Le, H.K.; Horne, D.M.; Silberglitt, R.S.

    1985-09-01

    This report assesses the energy conservation impact of surface modification technologies on the metalworking industries. The energy conservation impact of surface modification technologies on the metalworking industries is assessed by estimating their friction and wear tribological sinks and the subsequent reduction in these sinks when surface modified tools are used. Ion implantation, coatings, and laser and electron beam surface modifications are considered.

  5. Organic surface film contamination of Vitallium implants

    SciTech Connect

    Carter, J.M.; Flynn, H.E.; Meenaghan, M.A.; Natiella, J.R.; Akers, C.K.; Baier, R.E.

    1981-11-01

    Conventional finishing and polishing techniques used to prepare Vitallium subperiosteal dental implant castings were found to produce low energy surfaces as measured by critical surface tension. Standard metallographic preparation gave slightly higher values. Glow discharge cleaning of both types of polished surface gave much higher critical surface tension values. This suggests the presence of an organic film after surface polishing of the implant which may later affect tissue reaction, in particular attachment, as has been noticed in related animal studies.

  6. Ion implantation technology and ion sources

    NASA Astrophysics Data System (ADS)

    Sugitani, Michiro

    2014-02-01

    Ion implantation (I/I) technology has been developed with a great economic success of industries of VLSI (Very Large-Scale Integrated circuit) devices. Due to its large flexibility and good controllability, the I/I technology has been assuming various challenging requirements of VLSI evolutions, especially in advanced evolutional characteristics of CMOSFET. Here, reviewing the demands of VLSI manufacturing to the I/I technology, required characteristics of ion implanters, and their ion sources are discussed.

  7. Surface modification of implants in long bone.

    PubMed

    Förster, Yvonne; Rentsch, Claudia; Schneiders, Wolfgang; Bernhardt, Ricardo; Simon, Jan C; Worch, Hartmut; Rammelt, Stefan

    2012-01-01

    Coatings of orthopedic implants are investigated to improve the osteoinductive and osteoconductive properties of the implant surfaces and thus to enhance periimplant bone formation. By applying coatings that mimic the extracellular matrix a favorable environment for osteoblasts, osteoclasts and their progenitor cells is provided to promote early and strong fixation of implants. It is known that the early bone ongrowth increases primary implant fixation and reduces the risk of implant failure. This review presents an overview of coating titanium and hydroxyapatite implants with components of the extracellular matrix like collagen type I, chondroitin sulfate and RGD peptide in different small and large animal models. The influence of these components on cells, the inflammation process, new bone formation and bone/implant contact is summarized.

  8. Implant surfaces and design (Working Group 4).

    PubMed

    Lang, Niklaus P; Jepsen, Søren

    2009-09-01

    The remit of this working group (4) was to update existing knowledge on the effects of implant surface topography, composition and design on bone integration and re-osseointegration. Based on five narrative reviews that were performed following a defined search strategy, clinical implications as well as suggestions for further research have been formulated. The results and conclusions of the review processes in the following papers together with the group consensus, clinical implications and directions for future research are presented: 1. Effects of titanium surface topography on bone integration. 2. Effects of implant surface coatings and composition on bone integration (two reviews). 3. Effects of different implant surfaces and designs on marginal bone level alterations. 4. Re-osseointegration onto previously contaminated implant surfaces.

  9. Implantable Micropump Technologies for Murine Intracochlear Infusions

    PubMed Central

    Johnson, D. G.; Waldron, M. J.; Frisina, R. D.; Borkholder, D. A.

    2011-01-01

    Due to the very small size of the mouse inner ear, 600 nL volume, developing effective, controlled infusion systems is quite challenging. Key technologies have been created to minimize both size and power for an implantable pump for murine intracochlear infusions. A method for coupling fine capillary tubing to microfluidic channels is presented which provides low volume, biocompatible interconnects withstanding pressures as high as 827 kPa (120 psi) and consuming less than 20 nL of volume exiting in-plane with the pump. Surface micromachined resistive bridges integrated into the flow channel for anemometry based flow rate measurement have been optimized for low power operation in the ultra-low flow rate regime. A process for creation of deformable diaphragms over pump chambers with simultaneous coating of the microfluidic channels has been developed allowing integration of a biocompatible fluid flow path. These advances represent enabling capabilities for a drug delivery system suitable for space constrained applications such as subcutaneous implantation in mice. PMID:21096713

  10. Implantable micropump technologies for murine intracochlear infusions.

    PubMed

    Johnson, D G; Waldron, M J; Frisina, R D; Borkholder, D A

    2010-01-01

    Due to the very small size of the mouse inner ear, 600 nL volume, developing effective, controlled infusion systems is quite challenging. Key technologies have been created to minimize both size and power for an implantable pump for murine intracochlear infusions. A method for coupling fine capillary tubing to microfluidic channels is presented which provides low volume, biocompatible interconnects withstanding pressures as high as 827 kPa (120 psi) and consuming less than 20 nL of volume exiting in-plane with the pump. Surface micromachined resistive bridges integrated into the flow channel for anemometry based flow rate measurement have been optimized for low power operation in the ultra-low flow rate regime. A process for creation of deformable diaphragms over pump chambers with simultaneous coating of the microfluidic channels has been developed allowing integration of a biocompatible fluid flow path. These advances represent enabling capabilities for a drug delivery system suitable for space constrained applications such as subcutaneous implantation in mice.

  11. Advancing Binaural Cochlear Implant Technology

    PubMed Central

    McAlpine, David

    2015-01-01

    This special issue contains a collection of 13 papers highlighting the collaborative research and engineering project entitled Advancing Binaural Cochlear Implant Technology—ABCIT—as well as research spin-offs from the project. In this introductory editorial, a brief history of the project is provided, alongside an overview of the studies. PMID:26721929

  12. Microsystem technologies for ophtalmological implants

    NASA Astrophysics Data System (ADS)

    Mokwa, Wilfried

    2003-01-01

    Due to the low power consumption CMOS electronics is ideal for the use in implanted systems. This paper presents two projects working on ophthalmological implants. Both systems are powered by an external RF-field. One system has been developed to measure the intraocular pressure continuously which is important for the therapy of glaucoma patients. The system consists of a micro coil and an integrated pressure transponder chip built into an artificial soft lens. A second example is a very complex system for epiretinal stimulation of the nerve cells of the retina. With such a system it might be possible to give blind people that are suffering from retinitis pigmentosa some visual contact to their surrounding.

  13. Industrial applications of ion implantation into metal surfaces

    SciTech Connect

    Williams, J.M.

    1987-07-01

    The modern materials processing technique, ion implantation, has intriguing and attractive features that stimulate the imaginations of scientists and technologists. Success of the technique for introducing dopants into semiconductors has resulted in a stable and growing infrastructure of capital equipment and skills for use of the technique in the economy. Attention has turned to possible use of ion implantation for modification of nearly all surface related properties of materials - optical, chemical and corrosive, tribological, and several others. This presentation provides an introduction to fundamental aspects of equipment, technique, and materials science of ion implantation. Practical and economic factors pertaining to the technology are discussed. Applications and potential applications are surveyed. There are already available a number of ion-implanted products, including ball-and-roller bearings and races, punches-and-dies, injection screws for plastics molding, etc., of potential interest to the machine tool industry.

  14. TOPICAL REVIEW: Microsystem technologies for implantable applications

    NASA Astrophysics Data System (ADS)

    Receveur, Rogier A. M.; Lindemans, Fred W.; de Rooij, Nicolaas F.

    2007-05-01

    Microsystem technologies (MST) have become the basis of a large industry. The advantages of MST compared to other technologies provide opportunities for application in implantable biomedical devices. This paper presents a general and broad literature review of MST for implantable applications focused on the technical domain. A classification scheme is introduced to order the examples, basic technological building blocks relevant for implantable applications are described and finally a case study on the role of microsystems for one clinical condition is presented. We observe that the microfabricated parts span a wide range for implantable applications in various clinical areas. There are 94 active and 67 commercial 'end items' out of a total of 142. End item refers to the total concept, of which the microsystem may only be a part. From the 105 active end items 18 (13% of total number of end items) are classified as products. From these 18 products, there are only two for chronic use. The number of active end items in clinical, animal and proto phase for chronic use is 17, 13 and 20, respectively. The average year of first publication of chronic end items that are still in the animal or clinical phase is 1994 (n = 7) and 1993 (n = 11), respectively. The major technology market combinations are sensors for cardiovascular, drug delivery for drug delivery and electrodes for neurology and ophthalmology. Together these form 51% of all end items. Pressure sensors form the majority of sensors and there is just one product (considered to be an implantable microsystem) in the neurological area. Micro-machined ceramic packages, glass sealed packages and polymer encapsulations are used. Glass to metal seals are used for feedthroughs. Interconnection techniques such as flip chip, wirebonding or conductive epoxy as used in the semiconductor packaging and assembly industry are also used for manufacturing of implantable devices. Coatings are polymers or metal. As an alternative to

  15. Biofilm Disrupting Technology for Orthopedic Implants: What's on the Horizon?

    PubMed

    Connaughton, Alexander; Childs, Abby; Dylewski, Stefan; Sabesan, Vani J

    2014-01-01

    The use of orthopedic implants in joints has revolutionized the treatment of patients with many debilitating chronic musculoskeletal diseases such as osteoarthritis. However, the introduction of foreign material into the human body predisposes the body to infection. The treatment of these infections has become very complicated since the orthopedic implants serve as a surface for multiple species of bacteria to grow at a time into a resistant biofilm layer. This biofilm layer serves as a protectant for the bacterial colonies on the implant making them more resistant and difficult to eradicate when using standard antibiotic treatment. In some cases, the use of antibiotics alone has even made the bacteria more resistant to treatment. Thus, there has been surge in the creation of non-antibiotic anti-biofilm agents to help disrupt the biofilms on the orthopedic implants to help eliminate the infections. In this study, we discuss infections of orthopedic implants in the shoulder then we review the main categories of anti-biofilm agents that have been used for the treatment of infections on orthopedic implants. Then, we introduce some of the newer biofilm disrupting technology that has been studied in the past few years that may advance the treatment options for orthopedic implants in the future.

  16. Nanoscale Surface Modifications of Orthopaedic Implants: State of the Art and Perspectives

    PubMed Central

    Staruch, RMT; Griffin, MF; Butler, PEM

    2016-01-01

    Background: Orthopaedic implants such as the total hip or total knee replacement are examples of surgical interventions with postoperative success rates of over 90% at 10 years. Implant failure is associated with wear particles and pain that requires surgical revision. Improving the implant - bone surface interface is a key area for biomaterial research for future clinical applications. Current implants utilise mechanical, chemical or physical methods for surface modification. Methods: A review of all literature concerning the nanoscale surface modification of orthopaedic implant technology was conducted. Results: The techniques and fabrication methods of nanoscale surface modifications are discussed in detail, including benefits and potential pitfalls. Future directions for nanoscale surface technology are explored. Conclusion: Future understanding of the role of mechanical cues and protein adsorption will enable greater flexibility in surface control. The aim of this review is to investigate and summarise the current concepts and future directions for controlling the implant nanosurface to improve interactions. PMID:28217214

  17. Surface changes of implants after laser irradiation

    NASA Astrophysics Data System (ADS)

    Rechmann, Peter; Sadegh, Hamid M. M.; Goldin, Dan S.; Hennig, Thomas

    1999-05-01

    Periimplantitis is one of the major factors for the loss of dental implants. Due to the minor defense ability of the tissue surrounding the implant compared to natural teeth treatment of periimplantitis in the early stage is very important. Reducing bacteria with a laser might be the most successful step in therapy of periimplantitis. Aim of the study was to observe changes in surface morphology of seven different implants after irradiation with three different lasers. Two kinds of flat round samles were prepared by the manufacturers either identical to the body surface or to the cervical area of the corresponding implants. The samples were irradiated using different power settings. The lasers used were a CO2 laser (Uni Laser 450P, ASAH Medico Denmark; fiber guided, wavelength 10.6 μm, max. average power 8.3 W, "soft-pulse" and cw) an Er:YAG laser (KaVo Key Laser II, wavelength 2.94 μm, pulse duration 250-500μs, pulse energy 60-500 mJ, pulse repetition rate 1-15 Hz, focus diameter 620 μm, air-water cooling; Biberach, Germany; a frequency doubled Alexandrite laser (laboratory prototype, q-switched, fiber guided, wavelength 377 nm, pulse duration 1 μs, pulse repetition rate 30 Hz, water cooling). After irradiation the implant surfaces were investigated with a Scanning Electron Microscope. Ablation thresholds were determined. After CO2 laser irradiation no changes in surface morphology were observed whereas using the pulsed Er:YAG laser or frequency doubled Alexandrite laser even at low energies loss of integrity or melting of the surface was observed. The changes in surface morphology seem to depend very strongly on the type of surface coating.

  18. Evaluation of nano-technology-modified zirconia oral implants: a study in rabbits.

    PubMed

    Lee, Jaebum; Sieweke, Janet H; Rodriguez, Nancy A; Schüpbach, Peter; Lindström, Håkan; Susin, Cristiano; Wikesjö, Ulf M E

    2009-07-01

    The objective of this study was to screen candidate nano-technology-modified, micro-structured zirconia implant surfaces relative to local bone formation and osseointegration. Proprietary nano-technology surface-modified (calcium phosphate: CaP) micro-structured zirconia implants (A and C), control micro-structured zirconia implants (ZiUnite), and titanium porous oxide implants (TiUnite) were implanted into the femoral condyle in 40 adult male New Zealand White rabbits. Each animal received one implant in each hind leg; thus, 20 animals received A and C implants and 20 animals received ZiUnite and TiUnite implants in contralateral hind legs. Ten animals/group were euthanized at weeks 3 and 6 when biopsies of the implant sites were processed for histometric analysis using digital photomicrographs produced using backscatter scanning electron microscopy. The TiUnite surface demonstrated significantly greater bone-implant contact (BIC) (77.6+/-2.6%) compared with the A (64.6+/-3.6%) and C (62.2+/-3.1%) surfaces at 3 weeks (p<0.05). Numerical differences between ZiUnite (70.5+/-3.1%) and A and C surfaces did not reach statistical significance (p>0.05). Similarly, there were non-significant differences between the TiUnite and the ZiUnite surfaces (p>0.05). At 6 weeks, there were no significant differences in BIC between the TiUnite (67.1+/-4.2%), ZiUnite (69.7+/-5.7%), A (68.6+/-1.9%), and C (64.5+/-4.1%) surfaces (p>0.05). TiUnite and ZiUnite implant surfaces exhibit high levels of osseointegration that, in this model, confirm their advanced osteoconductive properties. Addition of CaP nano-technology to the ZiUnite surface does not enhance the already advanced osteoconductivity displayed by the TiUnite and ZiUnite implant surfaces.

  19. New advanced surface modification technique: titanium oxide ceramic surface implants: long-term clinical results

    NASA Astrophysics Data System (ADS)

    Szabo, Gyorgy; Kovacs, Lajos; Barabas, Jozsef; Nemeth, Zsolt; Maironna, Carlo

    2001-11-01

    The purpose of this paper is to discuss the background to advanced surface modification technologies and to present a new technique, involving the formation of a titanium oxide ceramic coating, with relatively long-term results of its clinical utilization. Three general techniques are used to modify surfaces: the addition or removal of material and the change of material already present. Surface properties can also be changed without the addition or removal of material, through the laser or electron beam thermal treatment. The new technique outlined in this paper relates to the production of a corrosion-resistant 2000-2500 A thick, ceramic oxide layer with a coherent crystalline structure on the surface of titanium implants. The layer is grown electrochemically from the bulk of the metal and is modified by heat treatment. Such oxide ceramic-coated implants have a number of advantageous properties relative to implants covered with various other coatings: a higher external hardness, a greater force of adherence between the titanium and the oxide ceramic coating, a virtually perfect insulation between the organism and the metal (no possibility of metal allergy), etc. The coated implants were subjected to various physical, chemical, electronmicroscopic, etc. tests for a qualitative characterization. Finally, these implants (plates, screws for maxillofacial osteosynthesis and dental root implants) were applied in surgical practice for a period of 10 years. Tests and the experience acquired demonstrated the good properties of the titanium oxide ceramic-coated implants.

  20. Digital technology in fixed implant prosthodontics.

    PubMed

    Joda, Tim; Ferrari, Marco; Gallucci, German O; Wittneben, Julia-Gabriela; Brägger, Urs

    2017-02-01

    Digital protocols are increasingly influencing prosthodontic treatment concepts. Implant-supported single-unit and short-span reconstructions will benefit mostly from the present digital trends. In these protocols, monolithic implant crowns connected to prefabricated titanium abutments, which are created based on data obtained from an intraoral scan followed by virtual design and production, without the need of a physical master cast, have to be considered in lieu of conventional manufacturing techniques for posterior implant restorations. No space for storage is needed in the complete digital workflow, and if a remake is required a replica of the original reconstruction can be produced quickly and inexpensively using rapid prototyping. The technological process is split into subtractive methods, such as milling or laser ablation, and additive processing, such as three-dimensional printing and selective laser melting. The dimensions of the supra-implant soft-tissue architecture can be calculated in advance of implant placement, according to the morphologic copy, and consequently are individualized for each patient. All these technologies have to be considered before implementing new digital dental workflows in daily routine. The correct indication and application are prerequisite and crucial for the success of the overall therapy, and, finally, for a satisfied patient. This includes a teamwork approach and equally affects the clinician, the dental assistant and the technician as well. The digitization process has the potential to change the entire dental profession. The major benefits will be reduced production costs, improvement in time efficiency and fulfilment of patients' perceptions of a modernized treatment concept.

  1. Antibacterial Surface Treatment for Orthopaedic Implants

    PubMed Central

    Gallo, Jiri; Holinka, Martin; Moucha, Calin S.

    2014-01-01

    It is expected that the projected increased usage of implantable devices in medicine will result in a natural rise in the number of infections related to these cases. Some patients are unable to autonomously prevent formation of biofilm on implant surfaces. Suppression of the local peri-implant immune response is an important contributory factor. Substantial avascular scar tissue encountered during revision joint replacement surgery places these cases at an especially high risk of periprosthetic joint infection. A critical pathogenic event in the process of biofilm formation is bacterial adhesion. Prevention of biomaterial-associated infections should be concurrently focused on at least two targets: inhibition of biofilm formation and minimizing local immune response suppression. Current knowledge of antimicrobial surface treatments suitable for prevention of prosthetic joint infection is reviewed. Several surface treatment modalities have been proposed. Minimizing bacterial adhesion, biofilm formation inhibition, and bactericidal approaches are discussed. The ultimate anti-infective surface should be “smart” and responsive to even the lowest bacterial load. While research in this field is promising, there appears to be a great discrepancy between proposed and clinically implemented strategies, and there is urgent need for translational science focusing on this topic. PMID:25116685

  2. Decontamination of dental implant surface in peri-implantitis treatment: A literature review

    PubMed Central

    Buitrago-Vera, Pedro; Solá-Ruiz, María F.; Ferrer-García, Juan C.

    2013-01-01

    Etiological treatment of peri-implantitis aims to reduce the bacterial load within the peri-implant pocket and decontaminate the implant surface in order to promote osseointegration. The aim of this literature review was to evaluate the efficacy of different methods of implant surface decontamination. A search was conducted using the PubMed (Medline) database, which identified 36 articles including in vivo and in vitro studies, and reviews of different decontamination systems (chemical, mechanical, laser and photodynamic therapies). There is sufficient consensus that, for the treatment of peri-implant infections, the mechanical removal of biofilm from the implant surface should be supplemented by chemical decontamination with surgical access. However, more long-term research is needed to confirm this and to establish treatment protocols responding to different implant characterics. Key words:Peri-implantitis, treatment, decontamination, implant surface, laser. PMID:23986023

  3. Comet Surface Sampling Technologies

    NASA Astrophysics Data System (ADS)

    Zacny, K.; Chu, P.; Paulsen, G.; Indyk, S.

    2014-06-01

    The goal of the Comet Surface Sample Return (CSSR) is to acquire and return to Earth a ≥500 cc) sample. Honeybee developed several sampling technologies including a standalone CSSR Probe (CSSRP) and Pyramid Comet Sampler (PyCoS).

  4. Surface morphology of RF plasma immersion H+ ion implanted and oxidized Si(100) surface

    NASA Astrophysics Data System (ADS)

    Anastasescu, M.; Stoica, M.; Gartner, M.; Bakalova, S.; Szekeres, A.; Alexandrova, S.

    2014-05-01

    The surface morphology of p-Si(100) wafers after RF plasma immersion (PII) H+ ion implantation into a shallow Si surface layer and after subsequent thermal oxidation was studied by atomic-force microscopic (AFM) imaging. After PII implantation of hydrogen ions with an energy of 2 keV and fluences ranging from 1013 cm-2 to 1015 cm-2 the Si wafers were oxidized in dry O2 at temperatures ranging from 700 °C to 800 °C. From the analysis of the AFM images, the surface amplitude parameters were evaluated and considered in terms of the technological conditions. The amplitude parameters showed a clear dependence on the H+ dose and the oxidation temperature, with the tendency of increasing with the increase of both the H+ ion fluence and the oxidation temperature. The implantation causes surface roughening, changing the RMS roughness value from 0.15 nm (typical for a polished Si(100) surface) to the highest value 0.6 nm for the H+ fluence of 1015 ions/cm2. Oxidation of the H+ implanted Si region, as the oxide is growing inward into Si, levels away the pits created by implants and results in a smoother surface, although keeping the RMS values larger than 0.2 nm.

  5. Antibacterial titanium surfaces for medical implants.

    PubMed

    Ferraris, S; Spriano, S

    2016-04-01

    Bacterial contamination is a critical problem in different fields (ranging from everyday life to space missions, and from medicine to biosensing). Specifically, in the case of medical implants, foreign materials are preferential sites for bacterial adhesion and microbial contamination, which can lead to the development of prosthetic infections. These problems can in turn lead to the necessity of a prolonged antibiotic therapy (which can last for years) and eventually to the removal of the device, with a consequent significant increase in the hospitalization times and costs, together with a stressful, painful and critical situation for the patient. Commercially pure titanium and its alloys are the most commonly used materials for permanent implants in contact with bone, and the prevention of infections on their surface is therefore a crucial challenge for orthopaedic and dental surgeons. The problem of the bacterial contamination of medical implants is briefly described in the first part of the present review. Then the most important inorganic antibacterial agents (Ag, Cu and Zn) are described, and this is followed by a review of the reported attempts of their introduction onto the surface of Ti-based substrates. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Design and manufacture of customized dental implants by using reverse engineering and selective laser melting technology.

    PubMed

    Chen, Jianyu; Zhang, Zhiguang; Chen, Xianshuai; Zhang, Chunyu; Zhang, Gong; Xu, Zhewu

    2014-11-01

    Recently a new therapeutic concept of patient-specific implant dentistry has been advanced based on computer-aided design/computer-aided manufacturing technology. However, a comprehensive study of the design and 3-dimensional (3D) printing of the customized implants, their mechanical properties, and their biomechanical behavior is lacking. The purpose of this study was to evaluate the mechanical and biomechanical performance of a novel custom-made dental implant fabricated by the selective laser melting technique with simulation and in vitro experimental studies. Two types of customized implants were designed by using reverse engineering: a root-analog implant and a root-analog threaded implant. The titanium implants were printed layer by layer with the selective laser melting technique. The relative density, surface roughness, tensile properties, bend strength, and dimensional accuracy of the specimens were evaluated. Nonlinear and linear finite element analysis and experimental studies were used to investigate the stress distribution, micromotion, and primary stability of the implants. Selective laser melting 3D printing technology was able to reproduce the customized implant designs and produce high density and strength and adequate dimensional accuracy. Better stress distribution and lower maximum micromotions were observed for the root-analog threaded implant model than for the root-analog implant model. In the experimental tests, the implant stability quotient and pull-out strength of the 2 types of implants indicated that better primary stability can be obtained with a root-analog threaded implant design. Selective laser melting proved to be an efficient means of printing fully dense customized implants with high strength and sufficient dimensional accuracy. Adding the threaded characteristic to the customized root-analog threaded implant design maintained the approximate geometry of the natural root and exhibited better stress distribution and

  7. The implant surface characteristics and peri-implantitis. An evidence-based update.

    PubMed

    Peixoto, C Davila; Almas, K

    2016-03-01

    Peri-implantitis is an inflammatory disease of the peri-implant mucosa with the loss of supporting bone. Because of the absence of an un-inflamed connective tissue zone between the healthy and diseased sites, peri-implant lesions are thought to progress more rapidly than periodontal lesions, suggesting the importance of early diagnosis and intervention if possible. A number of risk factors have been identified that may lead to the initiation and progression of peri-implant mucositis and peri-implantitis, eg., previous periodontal disease, poor plaque control, inability to clean, residual cement, smoking, genetic factors, diabetes, occlusal overload, rheumatoid arthritis, increased time of loading and alcohol consumption. At present there is not much literature available, highlighting the relationship between implant surface characteristics and peri-implant diseases. Implant surface characteristics vary with respect to topography, roughness and clinical composition, including turned, blasted, acid etched, porous sintered, oxidized, plasma sprayed and hydroxyapatite coated surfaces and their combinations. So the aim of this review is to explore the relationship between the characteristics of implant surface, the prevalence and incidence of peri-implantitis. This would help to identify plausible influence of surface characteristics, oral hygiene instructions and maintenance of implants for the long-term uneventful success of implant therapy.

  8. CO2 laser surface treatment of failed dental implants for re-implantation: an animal study.

    PubMed

    Kasraei, Shahin; Torkzaban, Parviz; Shams, Bahar; Hosseinipanah, Seyed Mohammad; Farhadian, Maryam

    2016-07-01

    The aim of the present study was to evaluate the success rate of failed implants re-implanted after surface treatment with CO2 laser. Despite the widespread use of dental implants, there are many incidents of failures. It is believed that lasers can be applied to decontaminate the implant surface without damaging the implant. Ten dental implants that had failed for various reasons other than fracture or surface abrasion were subjected to CO2 laser surface treatment and randomly placed in the maxillae of dogs. Three failed implants were also placed as the negative controls after irrigation with saline solution without laser surface treatment. The stability of the implants was evaluated by the use of the Periotest values (PTVs) on the first day after surgery and at 1, 3, and 6 months post-operatively. The mean PTVs of treated implants increased at the first month interval, indicating a decrease in implant stability due to inflammation followed by healing of the tissue. At 3 and 6 months, the mean PTVs decreased compared to the 1-month interval (P < 0.05), indicating improved implant stability. The mean PTVs increased in the negative control group compared to baseline (P < 0.05). Independent t-test showed that the mean PTVs of treated implants were significantly lower than control group at 3 and 6 months after implant placement (P < 0.05). Based on the PTVs, re-implantation of failed implants in Jack Russell Terrier dogs after CO2 laser surface debridement is associated with a high success rate in terms of implant stability.

  9. Basic research methods and current trends of dental implant surfaces.

    PubMed

    Coelho, Paulo G; Granjeiro, José M; Romanos, George E; Suzuki, Marcelo; Silva, Nelson R F; Cardaropoli, Giuseppe; Thompson, Van P; Lemons, Jack E

    2009-02-01

    Among dental implant design alterations, surface modifications have been by far the most investigated topic. Regarding implant surface research, the lack of hierarchical approaches relating in vitro, in vivo, clinical trials, and ex vivo analyses has hindered biomaterials scientists with clear informed rationale guidelines for implant surface design. This manuscript provides a critical hierarchical overview of the in vitro, laboratory in vivo, clinical, and ex vivo methodologies used to investigate the performance of novel biomaterials aiming to allow dental professionals to better evaluate the past, present, and future dental implant surface research. This manuscript also contains an overview of the commercially available surface texture and chemistry modifications including novel nanotechnology-based fabrication processes. Over the last decade, surface texturing has been the most utilized parameter for increasing the host-to-implant response. Recently, dental implant surfaces utilizing reduced length scale physico/chemical features (atomic and nanometric) have shown the potential to synergistically use both texture and the inclusion of bioactive ceramic components on the surface. Although surface modifications have been shown to enhance osseointegration at early implantation times, information concerning its long-term benefit to peri-implant tissues is lacking due to the reduced number of controlled clinical trials. Given the various implants/surfaces under study, the clinician should ask, founded on the basic hierarchical approach described for the in vitro, laboratory in vivo data, as well as the results of clinical studies to effectiveness before use of any dental implant.

  10. Comparative study on the osseointegration of implants in dog mandibles according to the implant surface treatment

    PubMed Central

    2016-01-01

    Objectives This study compared the impact of implant surface treatment on the stability and osseointegration of implants in dog mandibles. Materials and Methods Six adult dogs received a total of 48 implants that were prepared using four different surface treatments; resorbable blast media (RBM), hydroxyapatite (HA), hydrothermal-treated HA, and sand blasting and acid etching (SLA). Implants were installed, and dogs were separated into 2- and 4-week groups. Implant stability was evaluated via Periotest M, Osstell Mentor, and removal torque analyzers. A histomorphometric analysis was also performed. Results The stability evaluation showed that all groups generally had satisfactory values. The histomorphometric evaluation via a light microscope revealed that the HA surface implant group had the highest ratio of new bone formation on the entire fixture. The hydrothermal-treated HA surface implant group showed a high ratio of bone-to-implant contact in the upper half of the implant area. Conclusion The hydrothermal-treated HA implant improved the bone-to-implant contact ratio on the upper fixture, which increased the implant stability. PMID:28053904

  11. [Technological Set-up of Epiretinal Implants].

    PubMed

    Mokwa, W; Görtz, M

    2016-11-01

    In blinded patients, visual prostheses can restore visual perception by appropriate electrical stimulation of retinal nerve cells. This article presents the basic technological principles of retinal prostheses, using an epiretinal implantable visual prosthesis as example. An implantable visual prosthesis typically consists of extraocular and intraocular sections. The extraocular section is responsible for detecting the image. The information is derived from this image that is needed for appropriate electrical stimulation of the retinal nerve cells. Together with the necessary energy, these data are transmitted through a magnetic connection to the intraocular section. To ensure reliable transmission, the data are encoded. After transmission, energy and data are separated in the intraocular section, and the data are decoded. In accordance with the transmitted information, biphasic pulses of defined intensity and duration are produced on the simulation electrodes. In this way, ganglia cells are electrically stimulated and react with action potentials, which are transmitted to the visual cortex, where they lead to visual perception. Georg Thieme Verlag KG Stuttgart · New York.

  12. Implantable sensor technology: from research to clinical practice.

    PubMed

    Ledet, Eric H; D'Lima, Darryl; Westerhoff, Peter; Szivek, John A; Wachs, Rebecca A; Bergmann, Georg

    2012-06-01

    For decades, implantable sensors have been used in research to provide comprehensive understanding of the biomechanics of the human musculoskeletal system. These complex sensor systems have improved our understanding of the in vivo environment by yielding in vivo measurements of force, torque, pressure, and temperature. Historically, implants have been modified to be used as vehicles for sensors and telemetry systems. Recently, microfabrication and nanofabrication technology have sufficiently evolved that wireless, passive sensor systems can be incorporated into implants or tissue with minimal or no modification to the host implant. At the same time, sensor technology costs per unit have become less expensive, providing opportunities for use in daily clinical practice. Although diagnostic implantable sensors can be used clinically without significant increases in expense or surgical time, to date, orthopaedic smart implants have been used exclusively as research tools. These implantable sensors can facilitate personalized medicine by providing exquisitely accurate in vivo data unique to each patient.

  13. Decontamination of dental implant surface in peri-implantitis treatment: a literature review.

    PubMed

    Mellado-Valero, Ana; Buitrago-Vera, Pedro; Solá-Ruiz, María-Fernanda; Ferrer-García, Juan-Carlos

    2013-11-01

    Etiological treatment of peri-implantitis aims to reduce the bacterial load within the peri-implant pocket and decontaminate the implant surface in order to promote osseointegration. The aim of this literature review was to evaluate the efficacy of different methods of implant surface decontamination. A search was conducted using the PubMed (Medline) database, which identified 36 articles including in vivo and in vitro studies, and reviews of different decontamination systems (chemical, mechanical, laser and photodynamic therapies). There is sufficient consensus that, for the treatment of peri-implant infections, the mechanical removal of biofilm from the implant surface should be supplemented by chemical decontamination with surgical access. However, more long-term research is needed to confirm this and to establish treatment protocols responding to different implant characterics.

  14. Peri-implant medullary cisternae at the interface of bone-smooth surface titanium endosseous implant.

    PubMed

    Ruggeri, A; Strocchi, R; Franchi, M; Martini, D; Raspanti, M; Congiu, T; Ruggeri, A

    1999-01-01

    A histological and ultrastructural study was carried out on the spongy bone response to smooth titanium oral implant surfaces. The samples obtained both from monkeys and from patients at various times from the implant insertion revealed that the bone-implant integration developed through different morphological aspects. The implant surface appeared in contact with medullary lacunae, as well as with osteoid tissue or directly with bone matrix. The complementary ultrastructural techniques employed have shown that the medullary lacunae appeared as wide and flattened cisternae delimited by a continuous single layer of flattened cells forming a thin lamina adhering to the implant and an endosteal lamina facing the bone surface. For their position and flattened shape we named them peri-implant medullary cisternae. The presence of blood vessels, reticular cells and myeloid cells in their lumen suggested that these peri-implant medullary cisternae were functional sites of new bone formation.

  15. Plasma source ion-implantation technique for surface modification of materials

    NASA Astrophysics Data System (ADS)

    Conrad, J. R.; Radtke, J. L.; Dodd, R. A.; Worzala, Frank J.; Tran, Ngoc C.

    1987-12-01

    Plasma source ion-implantation (PSII) is a new ion-implantation technique which has been optimized for surface modification of materials such as metals, plastics, and ceramics. PSII departs radically from conventional implantation technology by circumventing the line-of-sight restriction inherent in conventional ion implantation. In PSII, targets to be implanted are placed directly in a plasma source and then pulse biased to a high negative potential. A plasma sheath forms around the target and ions bombard the entire target simultaneously. Preliminary experiments have demonstrated that PSII: (1) efficiently implants ions to concentrations and depths required for surface modification, (2) produces material with improved microhardness and wear properties, and (3) dramatically improves the life of manufacturing tools in actual industrial applications. For example, the tool life of M-2 pierce punches used to produce holes in mild steel plate has been increased by a factor of 80.

  16. Analysis of surface cleanliness of three commercial dental implants.

    PubMed

    Edwards, B N; Gold, B R

    1992-01-01

    Six routinely packaged commercially pure titanium dental implants (three commercial brands) were analysed using secondary ion mass spectrometry to examine the outermost surface layer. The aim of the analysis was to compare the surface purity (99.95%) of the implants with the substrate metal, common to all three brands. The use of a low primary ion current density provided a nominal protection limit of 0.01% or 100 p.p.m. All the implants examined had extremely pure surfaces. However, only one brand of implant had an ultraclean oxide surface in relation to the substrate.

  17. Melatonin plus porcine bone on discrete calcium deposit implant surface stimulates osteointegration in dental implants.

    PubMed

    Calvo-Guirado, José Luis; Gómez-Moreno, Gerardo; Barone, Antonio; Cutando, Antonio; Alcaraz-Baños, Miguel; Chiva, Fernando; López-Marí, Laura; Guardia, Javier

    2009-09-01

    The aim of this study was to evaluate the effect of the topical application of melatonin mixed with collagenized porcine bone to accelerate the osteointegration on the rough discrete calcium deposit (DCD) surface implants in Beagle dogs 3 months after their insertion. In preparation for subsequent insertion of dental implants, lower premolars and molars were extracted from 12 Beagle dogs. Each mandible received three parallel wall implants with discrete calcium deposit (DCD) surface of 4 mm in diameter and 10 mm in length. The implants were randomly assigned to the distal sites on each side of the mandible in three groups: group I implants alone, group II implants with melatonin and group III implants with melatonin and porcine bone. Prior to implanting, 5 mg lyophylized powdered melatonin was applied to one bone hole at each side of the mandible. None was applied at the control sites. Ten histological sections per implant were obtained for histomorphometric studies. After a 4-wk treatment period, melatonin significantly increased the perimeter of bone that was in direct contact with the treated implants (P < 0.0001), bone density (P < 0.0001), new bone formation (P < 0.0001) in comparison with control implants. Topical application of melatonin on DCD surface may act as a biomimetic agent in the placement of endo-osseous dental implants and enhance the osteointegration. Melatonin combined with porcine bone on DCD implants reveals more bone to implant contact at 12 wk (84.5 +/- 1.5%) compared with melatonin treated (75.1 +/- 1.4%) and nonmelatonin treated surface implants (64 +/- 1.4%).

  18. Implant Surface Design Regulates Mesenchymal Stem Cell Differentiation and Maturation.

    PubMed

    Boyan, B D; Cheng, A; Olivares-Navarrete, R; Schwartz, Z

    2016-03-01

    Changes in dental implant materials, structural design, and surface properties can all affect biological response. While bulk properties are important for mechanical stability of the implant, surface design ultimately contributes to osseointegration. This article reviews the surface parameters of dental implant materials that contribute to improved cell response and osseointegration. In particular, we focus on how surface design affects mesenchymal cell response and differentiation into the osteoblast lineage. Surface roughness has been largely studied at the microscale, but recent studies have highlighted the importance of hierarchical micron/submicron/nanosurface roughness, as well as surface roughness in combination with surface wettability. Integrins are transmembrane receptors that recognize changes in the surface and mediate downstream signaling pathways. Specifically, the noncanonical Wnt5a pathway has been implicated in osteoblastic differentiation of cells on titanium implant surfaces. However, much remains to be elucidated. Only recently have studies been conducted on the differences in biological response to implants based on sex, age, and clinical factors; these all point toward differences that advocate for patient-specific implant design. Finally, challenges in implant surface characterization must be addressed to optimize and compare data across studies. An understanding of both the science and the biology of the materials is crucial for developing novel dental implant materials and surface modifications for improved osseointegration. © International & American Associations for Dental Research 2016.

  19. Implant Surface Design Regulates Mesenchymal Stem Cell Differentiation and Maturation

    PubMed Central

    Boyan, B.D.; Cheng, A.; Olivares-Navarrete, R.; Schwartz, Z.

    2016-01-01

    Changes in dental implant materials, structural design, and surface properties can all affect biological response. While bulk properties are important for mechanical stability of the implant, surface design ultimately contributes to osseointegration. This article reviews the surface parameters of dental implant materials that contribute to improved cell response and osseointegration. In particular, we focus on how surface design affects mesenchymal cell response and differentiation into the osteoblast lineage. Surface roughness has been largely studied at the microscale, but recent studies have highlighted the importance of hierarchical micron/submicron/nanosurface roughness, as well as surface roughness in combination with surface wettability. Integrins are transmembrane receptors that recognize changes in the surface and mediate downstream signaling pathways. Specifically, the noncanonical Wnt5a pathway has been implicated in osteoblastic differentiation of cells on titanium implant surfaces. However, much remains to be elucidated. Only recently have studies been conducted on the differences in biological response to implants based on sex, age, and clinical factors; these all point toward differences that advocate for patient-specific implant design. Finally, challenges in implant surface characterization must be addressed to optimize and compare data across studies. An understanding of both the science and the biology of the materials is crucial for developing novel dental implant materials and surface modifications for improved osseointegration. PMID:26927483

  20. Surface Modifications and Their Effects on Titanium Dental Implants

    PubMed Central

    Jemat, A.; Ghazali, M. J.; Razali, M.; Otsuka, Y.

    2015-01-01

    This review covers several basic methodologies of surface treatment and their effects on titanium (Ti) implants. The importance of each treatment and its effects will be discussed in detail in order to compare their effectiveness in promoting osseointegration. Published literature for the last 18 years was selected with the use of keywords like titanium dental implant, surface roughness, coating, and osseointegration. Significant surface roughness played an important role in providing effective surface for bone implant contact, cell proliferation, and removal torque, despite having good mechanical properties. Overall, published studies indicated that an acid etched surface-modified and a coating application on commercial pure titanium implant was most preferable in producing the good surface roughness. Thus, a combination of a good surface roughness and mechanical properties of titanium could lead to successful dental implants. PMID:26436097

  1. Surface Modifications and Their Effects on Titanium Dental Implants.

    PubMed

    Jemat, A; Ghazali, M J; Razali, M; Otsuka, Y

    2015-01-01

    This review covers several basic methodologies of surface treatment and their effects on titanium (Ti) implants. The importance of each treatment and its effects will be discussed in detail in order to compare their effectiveness in promoting osseointegration. Published literature for the last 18 years was selected with the use of keywords like titanium dental implant, surface roughness, coating, and osseointegration. Significant surface roughness played an important role in providing effective surface for bone implant contact, cell proliferation, and removal torque, despite having good mechanical properties. Overall, published studies indicated that an acid etched surface-modified and a coating application on commercial pure titanium implant was most preferable in producing the good surface roughness. Thus, a combination of a good surface roughness and mechanical properties of titanium could lead to successful dental implants.

  2. The peri-implantitis: implant surfaces, microstructure, and physicochemical aspects.

    PubMed

    Mouhyi, Jaafar; Dohan Ehrenfest, David M; Albrektsson, Tomas

    2012-04-01

    There are two ways of looking at secondary failures of osseointegration; one is to reflect on possible causes for the failure, the other focuses on the pathology per se. In the first case, background factors such as mechanical trauma (adverse loading) or inflammations/infections are being discussed as the cause of failure. Then peri-implantitis is a term reserved for implant disturbance due to inflammation/infections only. However, irrespective of the original reason for the failure being adverse loading or inflammation/infection, the end result with bone resorption and inflammation may be very similar. Hence, in the present article, an alternative outlook has been chosen. Trigerring factors for peri-implantitis are generally gathered under four categories: lesions of peri-implant attachment, presence of aggressive bacteria, excessive mechanical stress, and corrosion. If only one of these factors would start a chain reaction leading to lesions, then the other factors may combine to worsen the condition. With other words, peri-implantitis is a general term dependent on a synergy of several factors, irrespective of the precise reason for first triggering off symptoms. © 2009 Wiley Periodicals, Inc.

  3. On implant surfaces: a review of current knowledge and opinions.

    PubMed

    Wennerberg, Ann; Albrektsson, Tomas

    2010-01-01

    The aims of the present review are (1) to identify essential surface parameters; (2) to present an overview of surface characteristics at the micrometer and nanometer levels of resolution relevant for the four most popular oral implant systems; (3) to discuss potential advantages of nanoroughness, hydrophilicity, and biochemical bonding; and (4) to suggest a hypothetical common mechanism behind strong bone responses to novel implant surfaces from different commercial companies. Oral implants from four major companies varied in average surface roughness (Sa) from 0.3 to 1.78 microm and in the developed surface area ratio (Sdr) from 24% to 143%, with the smoothest implants originating from Biomet 3i and the roughest from Institut Straumann. The original Branemark turned, machined surface had an Sa of 0.9 microm and an Sdr of 34%, making it clearly rougher than the smoothest implants examined. When evaluated for nanometer roughness, there was a substantial variation in Sa in the different implants from the four major companies. Novel implants from Biomet 3i, AstraTech, and Straumann differed from their respective predecessors in microroughness, physicochemical properties, and nano_roughness. When examined with scanning electron microscopy at high magnification, it was noted that these novel implant surfaces all had particular nanoroughness structures that were not present in their respective predecessors; this finding was suggested as a possible common mechanism behind the demonstrated stronger bone responses to these implants compared to adequate controls.

  4. Biologic response to titanium implants with laser-treated surfaces.

    PubMed

    Allegrini, Sergio; Yoshimoto, Marcelo; Salles, Marcos Barbosa; de Almeida Bressiani, Ana Helena

    2014-01-01

    To examine the biologic response to titanium implant surfaces treated with a neodymium:yttrium-aluminum-garnet laser. Sixty mini-implants made of grade 2 titanium were placed in the femora of 30 Wistar rats. Thirty implants had a machined surface and the other 30 had surfaces that were roughened by laser treatment. The animals were subdivided into three groups according to bone repair periods of 15, 30, and 60 days. The samples were observed under light and electron scanning microscopes and analyzed with the Student t test. Formation of new bone trabeculae toward the surface was apparent for the laser-treated implants at 15 days. Thin layers of bone matrix in intimate contact with the surface in the area of the central screw threads were observed, indicating high biocompatibility. Similar results were seen with machined implants after 30 days. A significant difference in bone formation was observed between the implant types at 15 days. Bone-to-implant contact was better on the surfaces subjected to laser treatment than on the machined titanium implants. The development of new laser treatments, which promote alterations in the surface energy as well as in the macro- and microstructures of titanium, may lead to improved bone-to-implant contact and thus better outcomes.

  5. Human study of ion implantation as a surface treatment for dental implants.

    PubMed

    De Maeztu, M A; Braceras, I; Álava, J I; Recio, C; Piñera, M; Gay-Escoda, C

    2013-07-01

    This clinical study evaluated a new surface treatment of ion implantation with CO ions which has previously been subjected to extensive study in animal models. The aim of this work was to assess its effect in humans. Experimental mini-implants were used; half of their longitudinal surface was machined and the other half was treated with CO ion implantation. The study was conducted in healthy volunteer patients who required prosthetic treatment with dental implants, and in accordance with the corresponding ethics committees. Coinciding with the insertion of commercial implants for oral restoration, one or two mini-implants were placed in the upper maxillary tuberosity or in the retromolar trigone of the mandible. The mini-implants were removed with a trephine jointly with a small volume of surrounding bone after a 3-month period. Two evaluation methods were used and both showed a greater degree of bone integration in the mini-implant section that underwent CO ion implantation treatment in comparison with the non-treated surface: 62.9% vs. 57.9%, and 54.8% vs. 46.2%. In addition, no adverse reactions were observed in the surface treatment with CO ion implantation. These results confirm the positive benefits in humans, based on the findings obtained from previous animal experiments.

  6. Changes in the surface of bone and acid-etched and sandblasted implants following implantation and removal

    PubMed Central

    Eroglu, Cennet Neslihan; Ertugrul, Abdullah Seckin; Eskitascioglu, Murat; Eskitascioglu, Gurcan

    2016-01-01

    Objective: The aim of this study was to determine whether there are any changes in the surface of bone or implant structures following the removal of a screwed dental implant. Materials and Methods: For this, six individual samples of acid-etched and sandblasted implants from three different manufacturers’ implant systems were used. They were screwed in a D1 bovine bone, and they were removed after primary stabilization. The bone and implant surfaces are evaluated with scanning electron microscope. Results: Through examination of the surfaces of the bone prior to implantation and of the used and unused implant surfaces, it was found that inhomogeneity in the implant surface can cause microcracking in the bone. Conclusions: This is attributed to the stress induced during the implantation of self-tapping implants and suggests that a tap drill may be required in some instances to protect the implant surface. PMID:27011744

  7. Surface insulating properties of titanium implanted alumina ceramics by plasma immersion ion implantation

    NASA Astrophysics Data System (ADS)

    Zhu, Mingdong; Song, Falun; Li, Fei; Jin, Xiao; Wang, Xiaofeng; Wang, Langping

    2017-09-01

    The insulating property of the alumina ceramic in vacuum under high voltage is mainly limited by its surface properties. Plasma immersion ion implantation (PIII) is an effective method to modify the surface chemical and physical properties of the alumina ceramic. In order to improve the surface flashover voltage of the alumina ceramic in vacuum, titanium ions with an energy of about 20 keV were implanted into the surface of the alumina ceramic using the PIII method. The surface properties of the as-implanted samples, such as the chemical states of the titanium, morphology and surface resistivity, were characterized by X-ray photoelectron spectroscopy, scanning electron microscope and electrometer, respectively. The surface flashover voltages of the as-implanted alumina samples were measured by a vacuum surface flashover experimental system. The XPS spectra revealed that a compound of Ti, TiO2 and Al2O3 was formed in the inner surface of the alumina sample. The electrometer results showed that the surface resistivity of the implanted alumina decreased with increased implantation time. In addition, after the titanium ion implantation, the maximum hold-off voltage of alumina was increased to 38.4 kV, which was 21.5% higher than that of the unimplanted alumina ceramic.

  8. Bone tissue response to plasma-nitrided titanium implant surfaces

    PubMed Central

    FERRAZ, Emanuela Prado; SVERZUT, Alexander Tadeu; FREITAS, Gileade Pereira; SÁ, Juliana Carvalho; ALVES, Clodomiro; BELOTI, Marcio Mateus; ROSA, Adalberto Luiz

    2015-01-01

    A current goal of dental implant research is the development of titanium (Ti) surfaces to improve osseointegration. Plasma nitriding treatments generate surfaces that favor osteoblast differentiation, a key event to the process of osteogenesis. Based on this, it is possible to hypothesize that plasma-nitrided Ti implants may positively impact osseointegration. Objective The aim of this study was to evaluate the in vivo bone response to Ti surfaces modified by plasma-nitriding treatments. Material and Methods Surface treatments consisted of 20% N2 and 80% H2, 450°C and 1.5 mbar during 1 h for planar and 3 h for hollow cathode. Untreated surface was used as control. Ten implants of each surface were placed into rabbit tibiae and 6 weeks post-implantation they were harvested for histological and histomorphometric analyses. Results Bone formation was observed in contact with all implants without statistically significant differences among the evaluated surfaces in terms of bone-to-implant contact, bone area between threads, and bone area within the mirror area. Conclusion Our results indicate that plasma nitriding treatments generate Ti implants that induce similar bone response to the untreated ones. Thus, as these treatments improve the physico-chemical properties of Ti without affecting its biocompatibility, they could be combined with modifications that favor bone formation in order to develop new implant surfaces. PMID:25760262

  9. Bone tissue response to plasma-nitrided titanium implant surfaces.

    PubMed

    Ferraz, Emanuela Prado; Sverzut, Alexander Tadeu; Freitas, Gileade Pereira; Sá, Juliana Carvalho; Alves, Clodomiro; Beloti, Marcio Mateus; Rosa, Adalberto Luiz

    2015-01-01

    A current goal of dental implant research is the development of titanium (Ti) surfaces to improve osseointegration. Plasma nitriding treatments generate surfaces that favor osteoblast differentiation, a key event to the process of osteogenesis. Based on this, it is possible to hypothesize that plasma-nitrided Ti implants may positively impact osseointegration. Objective The aim of this study was to evaluate the in vivo bone response to Ti surfaces modified by plasma-nitriding treatments. Material and Methods Surface treatments consisted of 20% N2 and 80% H2, 450°C and 1.5 mbar during 1 h for planar and 3 h for hollow cathode. Untreated surface was used as control. Ten implants of each surface were placed into rabbit tibiae and 6 weeks post-implantation they were harvested for histological and histomorphometric analyses. Results Bone formation was observed in contact with all implants without statistically significant differences among the evaluated surfaces in terms of bone-to-implant contact, bone area between threads, and bone area within the mirror area. Conclusion Our results indicate that plasma nitriding treatments generate Ti implants that induce similar bone response to the untreated ones. Thus, as these treatments improve the physico-chemical properties of Ti without affecting its biocompatibility, they could be combined with modifications that favor bone formation in order to develop new implant surfaces.

  10. Evaluating the Feasibility of Using Remote Technology for Cochlear Implants

    ERIC Educational Resources Information Center

    Goehring, Jenny L.; Hughes, Michelle L.; Baudhuin, Jacquelyn L.

    2012-01-01

    The use of remote technology to provide cochlear implant services has gained popularity in recent years. This article contains a review of research evaluating the feasibility of remote service delivery for recipients of cochlear implants. To date, published studies have determined that speech-processor programming levels and other objective tests…

  11. Evaluating the Feasibility of Using Remote Technology for Cochlear Implants

    ERIC Educational Resources Information Center

    Goehring, Jenny L.; Hughes, Michelle L.; Baudhuin, Jacquelyn L.

    2012-01-01

    The use of remote technology to provide cochlear implant services has gained popularity in recent years. This article contains a review of research evaluating the feasibility of remote service delivery for recipients of cochlear implants. To date, published studies have determined that speech-processor programming levels and other objective tests…

  12. Technological Innovations and Intervention Practices for Children with Cochlear Implants.

    ERIC Educational Resources Information Center

    Ertmer, David J.

    2002-01-01

    This epilogue to a forum on children with hearing impairments who have cochlear implants discusses innovation in implant technology and considers intervention issues. Key factors influencing outcomes are discussed, including educational programming, amount and length of communication intervention, and the targeting of both developmental and…

  13. A review of improved fixation methods for dental implants. Part I: Surface optimization for rapid osseointegration.

    PubMed

    Shibata, Yo; Tanimoto, Yasuhiro

    2015-01-01

    Titanium is a primary metallic biomaterial used in load-bearing orthopedic or dental implants because of its favorable mechanical properties and osseointegration capability. This article reviews the current status of surface optimization techniques for titanium implants, whether such concepts are in the form of sufficiently evidence-based, and highlights the related experimental tools. A strong emphasis was placed on the enhanced biological responses to titanium implants by modifying the surface finishing process. On this basis, a clear partition of surface chemistry and topography was critical. The intrinsic host tissue response to titanium implants is facilitated by the chemistry or topography of a passive oxide film, although the extent to which the surface characteristics enable rapid osseointegration is still uncertain. Besides the fundamental requirements, such as the promotion of osteogenic differentiation, the titanium implant surface should accelerate wound-healing phenomena prior to bone ingrowth toward the surface. Moreover, because initial bacterial attachment to the implant surface is unavoidable, infection control by surface modification is also an important determinant in reducing surgical failure. A desirable surface-biological relationship often needs to be characterized at the nanoscale by means of advanced technologies. Copyright © 2014 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

  14. Comparison of peri-implant bone formation around injection-molded and machined surface zirconia implants in rabbit tibiae.

    PubMed

    Kim, Hong-Kyun; Woo, Kyung Mi; Shon, Won-Jun; Ahn, Jin-Soo; Cha, Seunghee; Park, Young-Seok

    2015-01-01

    The aim of this study was to compare osseointegration and surface characteristics of zirconia implants made by the powder injection molding (PIM) technique against those made by the conventional milling procedure in rabbit tibiae. Surface characteristics of 2 types of implants were evaluated. Sixteen rabbits received 2 types of external hex implants with similar geometry, either machined zirconia implants or PIM zirconia implants, in the tibiae. Removal torque tests and histomorphometric analyses were performed. The roughness of the PIM zirconia implants was higher than that of machined zirconia implants. The PIM zirconia implants exhibited significantly higher bone-implant contact and removal torque values than the machined zirconia implants (p<0.001). The osseointegration of the PIM zirconia implant is promising, and PIM, using the roughened mold etching technique, can produce substantially rougher surfaces on zirconia implants.

  15. Temperature dependent surface modification of T91 steel under 3.25 MeV Fe-ion implantation

    NASA Astrophysics Data System (ADS)

    Zhu, Huiping; Wang, Zhiguang; Cui, Minghuan; Li, Bingsheng; Gao, Xing; Sun, Jianrong; Yao, Cunfeng; Wei, Kongfang; Shen, Tielong; Pang, Lilong; Zhu, Yabin; Li, Yuanfei; Wang, Ji; Xie, Erqing

    2015-01-01

    Ion implantation is an established technique for modifying the surface properties of a wide range of materials. In this research, temperature dependent surface modification induced by Fe-ion implantation in T91 steel was investigated. The T91 samples were implanted with 3.25 MeV Fe-ions to fluence of 1.7 × 1016 ions/cm2 at room temperature, 300 and 450 °C, respectively. After implantation, the T91 samples were characterized by means of positron annihilation Doppler broadening spectroscopy (PADBS) and nano-indention technology (NIT). It was found that the concentration of open-volume defects in T91 samples decreased with increasing implantation temperature. From NIT analysis, it was found that all the samples were hardened after implantation and the hardness of the implanted T91 samples increased with increasing implantation temperature.

  16. Improving mechanical properties of polyethylene orthopaedic implants by high frequency cold plasma surface activation

    NASA Astrophysics Data System (ADS)

    Tudoran, Cristian D.; Vlad, Iulia E.; Dadarlat, Dorin N.; Anghel, Sorin D.

    2013-11-01

    Although a tremendous progress has been made in developing new methods and materials for manufacturing orthopaedic implants, the new technology still faces various problems. Polyethylene implants are relatively easy to manufacture and at lower cost compared to metallic or ceramic implants, but they present a fundamental problem: during usage and in time, due to their manufacturing technology, the material suffers from pitting and delamination which leads to crack propagation and finally to sudden fracture. Our studies and tests performed on polyethylene showed that, using cold plasma surface activation during the manufacturing process of the orthopaedic implants made from polyethylene can significantly increase their mechanical properties. The breaking tests revealed an increase of the tensile strength in the laminated polyethylene samples by a factor of 4 after plasma activation. "Aging" tests have been also performed to investigate how the cold plasma treated samples maintain their properties in time, after the surface activation process.

  17. Microbattery technologies for miniaturized implantable medical devices.

    PubMed

    Nathan, Menachem

    2010-06-01

    Implanted medical devices (IMDs), in particular neuro-stimulators, drug delivery chips and cochlear implants are undergoing miniaturization. Some of these miniaturized IMDs are "active" in the sense that they require a power source for operation. In most cases, the ideal power source needs to be an implanted battery of dimensions similar to that of the device. The state-of-the-art of battery miniaturization is reviewed with emphasis on novel Li and Li-ion two- and three-dimensional thin-film microbatteries. It is shown that three-dimensional thin-film batteries may provide a solution to the power requirements of miniaturized IMDs.

  18. Surface modification of sapphire by ion implantation

    SciTech Connect

    McHargue, C.J.

    1998-11-01

    The range of microstructures and properties of sapphire (single crystalline Al{sub 2}O{sub 3}) that are produced by ion implantation are discussed with respect to the implantation parameters of ion species, fluence, irradiation temperature and the orientation of the ion beam relative to crystallographic axes. The microstructure of implanted sapphire may be crystalline with varying concentrations of defects or it may be amorphous perhaps with short-range order. At moderate to high fluences, implanted metallic ions often coalesce into pure metallic colloids and gas ions form bubbles. Many of the implanted microstructural features have been identified from studies using transmission electron microscopy (TEM), optical spectroscopy, Moessbauer spectroscopy, and Rutherford backscattering-channeling. The chemical, mechanical, and physical properties reflect the microstructures.

  19. Air Abrasive Disinfection of Implant Surfaces in a Simulated Model of Peri-Implantitis

    DTIC Science & Technology

    2016-06-01

    A thesis submitted to the Faculty of the Periodontics Graduate Program Naval Postgraduate Dental School Uniformed Services University of the...Abrasive Disinfection of Implant Surfaces in a Simulated Model of Peri-Implantitis David G. Quintero Certificate in Periodontics , Periodontics ...reduction in bacteria may allow the host response to better combat remaining periodontal pathogens and initiate healing. When compared to

  20. Materials and technologies for soft implantable neuroprostheses

    NASA Astrophysics Data System (ADS)

    Lacour, Stéphanie P.; Courtine, Grégoire; Guck, Jochen

    2016-10-01

    Implantable neuroprostheses are engineered systems designed to restore or substitute function for individuals with neurological deficits or disabilities. These systems involve at least one uni- or bidirectional interface between a living neural tissue and a synthetic structure, through which information in the form of electrons, ions or photons flows. Despite a few notable exceptions, the clinical dissemination of implantable neuroprostheses remains limited, because many implants display inconsistent long-term stability and performance, and are ultimately rejected by the body. Intensive research is currently being conducted to untangle the complex interplay of failure mechanisms. In this Review, we emphasize the importance of minimizing the physical and mechanical mismatch between neural tissues and implantable interfaces. We explore possible materials solutions to design and manufacture neurointegrated prostheses, and outline their immense therapeutic potential.

  1. Bone Response to Surface-Modified Titanium Implants: Studies on the Early Tissue Response to Implants with Different Surface Characteristics

    PubMed Central

    Larsson Wexell, C.; Thomsen, P.; Aronsson, B.-O.; Tengvall, P.; Rodahl, M.; Lausmaa, J.; Kasemo, B.; Ericson, L. E.

    2013-01-01

    In a series of experimental studies, the bone formation around systematically modified titanium implants is analyzed. In the present study, three different surface modifications were prepared and evaluated. Glow-discharge cleaning and oxidizing resulted in a highly stoichiometric TiO2 surface, while a glow-discharge treatment in nitrogen gas resulted in implants with essentially a surface of titanium nitride, covered with a very thin titanium oxide. Finally, hydrogen peroxide treatment of implants resulted in an almost stoichiometric TiO2, rich in hydroxyl groups on the surface. Machined commercially pure titanium implants served as controls. Scanning Auger Electron Spectroscopy, Scanning Electron Microscopy, and Atomic Force Microscopy revealed no significant differences in oxide thickness or surface roughness parameters, but differences in the surface chemical composition and apparent topography were observed. After surface preparation, the implants were inserted in cortical bone of rabbits and evaluated after 1, 3, and 6 weeks. Light microscopic evaluation of the tissue response showed that all implants were in contact with bone and had a large proportion of newly formed bone within the threads after 6 weeks. There were no morphological differences between the four groups. Our study shows that a high degree of bone contact and bone formation can be achieved with titanium implants of different surface composition and topography. PMID:24174936

  2. Biofunctionalization of surfaces by energetic ion implantation: Review of progress on applications in implantable biomedical devices and antibody microarrays

    NASA Astrophysics Data System (ADS)

    Bilek, Marcela M. M.

    2014-08-01

    Despite major research efforts in the field of biomaterials, rejection, severe immune responses, scar tissue and poor integration continue to seriously limit the performance of today's implantable biomedical devices. Implantable biomaterials that interact with their host via an interfacial layer of active biomolecules to direct a desired cellular response to the implant would represent a major and much sought after improvement. Another, perhaps equally revolutionary, development that is on the biomedical horizon is the introduction of cost-effective microarrays for fast, highly multiplexed screening for biomarkers on cell membranes and in a variety of analyte solutions. Both of these advances will rely on effective methods of functionalizing surfaces with bioactive molecules. After a brief introduction to other methods currently available, this review will describe recently developed approaches that use energetic ions extracted from plasma to facilitate simple, one-step covalent surface immobilization of bioactive molecules. A kinetic theory model of the immobilization process by reactions with long-lived, mobile, surface-embedded radicals will be presented. The roles of surface chemistry and microstructure of the ion treated layer will be discussed. Early progress on applications of this technology to create diagnostic microarrays and to engineer bioactive surfaces for implantable biomedical devices will be reviewed.

  3. Nanotubular surface modification of metallic implants via electrochemical anodization technique

    PubMed Central

    Wang, Lu-Ning; Jin, Ming; Zheng, Yudong; Guan, Yueping; Lu, Xin; Luo, Jing-Li

    2014-01-01

    Due to increased awareness and interest in the biomedical implant field as a result of an aging population, research in the field of implantable devices has grown rapidly in the last few decades. Among the biomedical implants, metallic implant materials have been widely used to replace disordered bony tissues in orthopedic and orthodontic surgeries. The clinical success of implants is closely related to their early osseointegration (ie, the direct structural and functional connection between living bone and the surface of a load-bearing artificial implant), which relies heavily on the surface condition of the implant. Electrochemical techniques for modifying biomedical implants are relatively simple, cost-effective, and appropriate for implants with complex shapes. Recently, metal oxide nanotubular arrays via electrochemical anodization have become an attractive technique to build up on metallic implants to enhance the biocompatibility and bioactivity. This article will thoroughly review the relevance of electrochemical anodization techniques for the modification of metallic implant surfaces in nanoscale, and cover the electrochemical anodization techniques used in the development of the types of nanotubular/nanoporous modification achievable via electrochemical approaches, which hold tremendous potential for bio-implant applications. In vitro and in vivo studies using metallic oxide nanotubes are also presented, revealing the potential of nanotubes in biomedical applications. Finally, an outlook of future growth of research in metallic oxide nanotubular arrays is provided. This article will therefore provide researchers with an in-depth understanding of electrochemical anodization modification and provide guidance regarding the design and tuning of new materials to achieve a desired performance and reliable biocompatibility. PMID:25258532

  4. Nanotubular surface modification of metallic implants via electrochemical anodization technique.

    PubMed

    Wang, Lu-Ning; Jin, Ming; Zheng, Yudong; Guan, Yueping; Lu, Xin; Luo, Jing-Li

    2014-01-01

    Due to increased awareness and interest in the biomedical implant field as a result of an aging population, research in the field of implantable devices has grown rapidly in the last few decades. Among the biomedical implants, metallic implant materials have been widely used to replace disordered bony tissues in orthopedic and orthodontic surgeries. The clinical success of implants is closely related to their early osseointegration (ie, the direct structural and functional connection between living bone and the surface of a load-bearing artificial implant), which relies heavily on the surface condition of the implant. Electrochemical techniques for modifying biomedical implants are relatively simple, cost-effective, and appropriate for implants with complex shapes. Recently, metal oxide nanotubular arrays via electrochemical anodization have become an attractive technique to build up on metallic implants to enhance the biocompatibility and bioactivity. This article will thoroughly review the relevance of electrochemical anodization techniques for the modification of metallic implant surfaces in nanoscale, and cover the electrochemical anodization techniques used in the development of the types of nanotubular/nanoporous modification achievable via electrochemical approaches, which hold tremendous potential for bio-implant applications. In vitro and in vivo studies using metallic oxide nanotubes are also presented, revealing the potential of nanotubes in biomedical applications. Finally, an outlook of future growth of research in metallic oxide nanotubular arrays is provided. This article will therefore provide researchers with an in-depth understanding of electrochemical anodization modification and provide guidance regarding the design and tuning of new materials to achieve a desired performance and reliable biocompatibility.

  5. Nanomaterials and synergistic low intensity direct current (LIDC) stimulation technology for orthopaedic implantable medical devices

    PubMed Central

    Samberg, Meghan E.; Cohen, Paul H.; Wysk, Richard A.; Monteiro-Riviere, Nancy A.

    2012-01-01

    Nanomaterials play a significant role in biomedical research and applications due to their unique biological, mechanical, and electrical properties. In recent years, they have been utilised to improve the functionality and reliability of a wide range of implantable medical devices ranging from well-established orthopaedic residual hardware devices (e.g. hip implants) that can repair defects in skeletal systems to emerging tissue engineering scaffolds that can repair or replace organ functions. This review summarizes the applications and efficacies of these nanomaterials that include synthetic or naturally occurring metals, polymers, ceramics, and composites in orthopaedic implants, the largest market segment of implantable medical devices. The importance of synergistic engineering techniques that can augment or enhance the performance of nanomaterial applications in orthopaedic implants is also discussed,, the focus being on a low intensity direct electric current (LIDC) stimulation technology to promote the long-term antibacterial efficacy of oligodynamic metal-based surfaces by ionization, while potentially accelerating tissue growth and osseointegration. While many nanomaterials have clearly demonstrated their ability to provide more effective implantable medical surfaces, further decisive investigations are necessary before they can translate into medically safe and commercially viable clinical applications. The paper concludes with a discussion about some of the critical impending issues with the application of nanomaterials-based technologies in implantable medical devices, and potential directions to address these. PMID:23335493

  6. Nanomaterials and synergistic low-intensity direct current (LIDC) stimulation technology for orthopedic implantable medical devices.

    PubMed

    Shirwaiker, Rohan A; Samberg, Meghan E; Cohen, Paul H; Wysk, Richard A; Monteiro-Riviere, Nancy A

    2013-01-01

    Nanomaterials play a significant role in biomedical research and applications because of their unique biological, mechanical, and electrical properties. In recent years, they have been utilized to improve the functionality and reliability of a wide range of implantable medical devices ranging from well-established orthopedic residual hardware devices (e.g., hip implants) that can repair defects in skeletal systems to emerging tissue engineering scaffolds that can repair or replace organ functions. This review summarizes the applications and efficacies of these nanomaterials that include synthetic or naturally occurring metals, polymers, ceramics, and composites in orthopedic implants, the largest market segment of implantable medical devices. The importance of synergistic engineering techniques that can augment or enhance the performance of nanomaterial applications in orthopedic implants is also discussed, the focus being on a low-intensity direct electric current (LIDC) stimulation technology to promote the long-term antibacterial efficacy of oligodynamic metal-based surfaces by ionization, while potentially accelerating tissue growth and osseointegration. While many nanomaterials have clearly demonstrated their ability to provide more effective implantable medical surfaces, further decisive investigations are necessary before they can translate into medically safe and commercially viable clinical applications. The article concludes with a discussion about some of the critical impending issues with the application of nanomaterials-based technologies in implantable medical devices, and potential directions to address these. Copyright © 2013 Wiley Periodicals, Inc.

  7. Impact of Dental Implant Surface Modifications on Osseointegration

    PubMed Central

    Smeets, Ralf; Stadlinger, Bernd; Schwarz, Frank; Beck-Broichsitter, Benedicta; Jung, Ole; Precht, Clarissa; Kloss, Frank; Gröbe, Alexander; Heiland, Max

    2016-01-01

    Objective. The aim of this paper is to review different surface modifications of dental implants and their effect on osseointegration. Common marketed as well as experimental surface modifications are discussed. Discussion. The major challenge for contemporary dental implantologists is to provide oral rehabilitation to patients with healthy bone conditions asking for rapid loading protocols or to patients with quantitatively or qualitatively compromised bone. These charging conditions require advances in implant surface design. The elucidation of bone healing physiology has driven investigators to engineer implant surfaces that closely mimic natural bone characteristics. This paper provides a comprehensive overview of surface modifications that beneficially alter the topography, hydrophilicity, and outer coating of dental implants in order to enhance osseointegration in healthy as well as in compromised bone. In the first part, this paper discusses dental implants that have been successfully used for a number of years focusing on sandblasting, acid-etching, and hydrophilic surface textures. Hereafter, new techniques like Discrete Crystalline Deposition, laser ablation, and surface coatings with proteins, drugs, or growth factors are presented. Conclusion. Major advancements have been made in developing novel surfaces of dental implants. These innovations set the stage for rehabilitating patients with high success and predictable survival rates even in challenging conditions. PMID:27478833

  8. Method For Silicon Surface Texturing Using Ion Implantation

    SciTech Connect

    Kadakia, Nirag; Naczas, Sebastian; Bakhru, Hassaram; Huang Mengbing

    2011-06-01

    As the semiconductor industry continues to show more interest in the photovoltaic market, cheaper and readily integrable methods of silicon solar cell production are desired. One of these methods - ion implantation - is well-developed and optimized in all commercial semiconductor fabrication facilities. Here we have developed a silicon surface texturing technique predicated upon the phenomenon of surface blistering of H-implanted silicon, using only ion implantation and thermal annealing. We find that following the H implant with a second, heavier implant markedly enhances the surface blistering, causing large trenches that act as a surface texturing of c-Si. We have found that this method reduces total broadband Si reflectance from 35% to below 5percent;. In addition, we have used Rutherford backscattering/channeling measurements investigate the effect of ion implantation on the crystallinity of the sample. The data suggests that implantation-induced lattice damage is recovered upon annealing, reproducing the original monocrystalline structure in the previously amorphized region, while at the same time retaining the textured surface.

  9. Laminin coatings on implant surfaces promote osseointegration: Fact or fiction?

    PubMed

    Javed, Fawad; Al Amri, Mohammad D; Kellesarian, Sergio Varela; Al-Askar, Mansour; Al-Kheraif, Abdulaziz A; Romanos, Georgios E

    2016-08-01

    To our knowledge from indexed literature, the role of laminins in the expression of osteogenic biomarkers and osseointegration enhancement has not been systematically reviewed. The aim of the present systematic review was to assess the role of laminin coatings on implant surfaces in promoting osseointegration. To address the focused question, "Do laminin coatings on implant surfaces influence osseointegration?", indexed databases were searched from 1965 up to and including November 2015 using various combination of the following keywords: "Bone to implant contact"; "implant"; "laminins"; and "osseointegration". Letters to the Editor, case-reports/case-series, historic reviews, and commentaries were excluded. The pattern of the present systematic review was customized to primarily summarize the pertinent data. Nine studies were included. Six studies were prospective and were performed in animals and 5 studies were in vitro. Results from 8 studies showed that laminin coatings enhanced new bone formation around implants and/or bone-to-implant contact. One study showed that laminin coated implants surfaces did not improve osseointegration. On experimental grounds, laminin coatings seem to enhance osteogenic biomarkers expression and/or osseointegration; however, from a clinical perspective, further randomized control trials are needed to assess the role of laminin coatings in promoting osseointegration around dental implants. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

  10. Surgical implants and technologies for cartilage repair and preservation of the knee.

    PubMed

    Stroh, D Alex; Johnson, Aaron J; Mont, Michael A

    2011-05-01

    Focal lesions of the articular cartilage of the knee can be managed with a variety of products and technologies in an attempt to restore function to the afflicted joint and forestall the need for possible total knee arthroplasty. Among these approaches are non-implant-based procedures (arthroscopic chondroplasty and microfracture), grafting procedures (autografts/mosaicplasty and allografts), cell-based procedures (autologous chondrocyte implantation) and nonbiologic implants (metallic plugs and cell-free polymers). For each clinically established procedure there are also a number of investigational variations that aim to improve the in vivo quality of the regenerated/restored cartilage surface. This article analyzes existing and developing non-implant- and graft-based technologies for the repair or restoration of the articular cartilage of the knee based on a review of the published literature.

  11. Titanium dental implant surfaces obtained by anodic spark deposition - From the past to the future.

    PubMed

    Kaluđerović, Milena R; Schreckenbach, Joachim P; Graf, Hans-Ludwig

    2016-12-01

    stability of the implants. Additionally, potential innovations in this field such as fabrication of nanotubes on the implant surfaces as well as novel approaches (e.g. coating with proteins, nanostructured topography; combining implant body and surface derived from titanium and zirconia) are elaborated in this review. Besides, biochemical aspects on implant surface cell/tissue interaction are summarized. From the clinical point of view implant surfaces fabricated by ASD technology possess fast and improved osseointegration, high healing rates and long term prognosis.

  12. Detoxification of Implant Surfaces Affected by Peri-Implant Disease: An Overview of Surgical Methods

    PubMed Central

    Wilson Jr, Thomas G.

    2013-01-01

    Purpose. Peri-implantitis is one of the major causes of implant failure. The detoxification of the implant surface is necessary to obtain reosseointegration. The aim of this review was to summarize in vitro and in vivo studies as well as clinical trials that have evaluated surgical approaches for detoxification of the implant body surfaces. Materials and Methods. A literature search was conducted using MEDLINE (PubMed) from 1966 to 2013. The outcome variables were the ability of the therapeutic method to eliminate the biofilm and endotoxins from the implant surface, the changes in clinical parameters, radiographic bone fill, and histological reosseointegration. Results. From 574 articles found, 76 were analyzed. The findings, advantages, and disadvantages of using mechanical, chemical methods and lasers are discussed. Conclusions. Complete elimination of the biofilms is difficult to achieve. All therapies induce changes of the chemical and physical properties of the implant surface. Partial reosseointegration after detoxification has been reported in animals. Combination protocols for surgical treatment of peri-implantitis in humans have shown some positive clinical and radiographic results, but long-term evaluation to evaluate the validity and reliability of the techniques is needed. PMID:23983691

  13. Ion sources for ion implantation technology (invited)

    NASA Astrophysics Data System (ADS)

    Sakai, Shigeki; Hamamoto, Nariaki; Inouchi, Yutaka; Umisedo, Sei; Miyamoto, Naoki

    2014-02-01

    Ion sources for ion implantation are introduced. The technique is applied not only to large scale integration (LSI) devices but also to flat panel display. For LSI fabrication, ion source scheduled maintenance cycle is most important. For CMOS image sensor devices, metal contamination at implanted wafer is most important. On the other hand, to fabricate miniaturized devices, cluster ion implantation has been proposed to make shallow PN junction. While for power devices such as silicon carbide, aluminum ion is required. For doping processes of LCD fabrication, a large ion source is required. The extraction area is about 150 cm × 10 cm, and the beam uniformity is important as well as the total target beam current.

  14. Ion sources for ion implantation technology (invited)

    SciTech Connect

    Sakai, Shigeki Hamamoto, Nariaki; Inouchi, Yutaka; Umisedo, Sei; Miyamoto, Naoki

    2014-02-15

    Ion sources for ion implantation are introduced. The technique is applied not only to large scale integration (LSI) devices but also to flat panel display. For LSI fabrication, ion source scheduled maintenance cycle is most important. For CMOS image sensor devices, metal contamination at implanted wafer is most important. On the other hand, to fabricate miniaturized devices, cluster ion implantation has been proposed to make shallow PN junction. While for power devices such as silicon carbide, aluminum ion is required. For doping processes of LCD fabrication, a large ion source is required. The extraction area is about 150 cm × 10 cm, and the beam uniformity is important as well as the total target beam current.

  15. Microscopic Study of Surface Microtopographic Characteristics of Dental Implants

    PubMed Central

    Sezin, M.; Croharé, L.; Ibañez, J.C.

    2016-01-01

    Objective: To determine and compare the micro topographic characteristics of dental implants submitted to different surface treatments, using scanning electron microscopy (SEM). Materials and Methods: Implants were divided into 7 groups of 3 specimens each, according to the surface treatment used: group 1: Osseotite, BIOMET 3i; group 2: SLA surface, Institut Straumann AG; group 3: Oxalife surface, Tree-Oss implant; group 4: B&W implant surface; group 5: Q-implant surface; group 6: ML implant surface; group 7: RBM surface, Rosterdent implant. The surfaces were examined under SEM (Carl Zeiss FE-SEM-SIGMA). Image Proplus software was used to determine the number and mean diameter of pores per area unit (mm). The data obtained were analyzed with the Mann-Whitney test. A confocal laser microscope (LEXT-OLS4100 Olympus) was used to conduct the comparative study of surface roughness (Ra). Data were analyzed using Tukey's HSD test. Results: The largest average pore diameter calculated in microns was found in group 5 (3.45 µm+/-1.91) while the smallest in group 7 (1.47µm+/-1.29). Significant differences were observed among each one of the groups studied (p<0.05). The largest number of pores/mm2 was found in group 2 (229343) and the smallest number in group 4 (10937). Group 2 showed significant differences regarding the other groups (p<0.05). The greatest roughness (Ra) was observed in group 2 (0.975µm+/-0.115) and the smallest in group 4 (0.304µm+/-0.063). Group 2 was significantly different from the other groups (p<0.05). Conclusion: The micro topography observed in the different groups presented dissimilar and specific features, depending on the chemical treatment used for the surfaces.. PMID:27335615

  16. Surface Engineering of Nanostructured Titanium Implants with Bioactive Ions.

    PubMed

    Kim, H-S; Kim, Y-J; Jang, J-H; Park, J-W

    2016-05-01

    Surface nanofeatures and bioactive ion chemical modification are centrally important in current titanium (Ti) oral implants for enhancing osseointegration. However, it is unclear whether the addition of bioactive ions definitively enhances the osteogenic capacity of a nanostructured Ti implant. We systematically investigated the osteogenesis process of human multipotent adipose stem cells triggered by bioactive ions in the nanostructured Ti implant surface. Here, we report that bioactive ion surface modification (calcium [Ca] or strontium [Sr]) and resultant ion release significantly increase osteogenic activity of the nanofeatured Ti surface. We for the first time demonstrate that ion modification actively induces focal adhesion development and expression of critical adhesion–related genes (vinculin, talin, and RHOA) of human multipotent adipose stem cells, resulting in enhanced osteogenic differentiation on the nanofeatured Ti surface. It is also suggested that fibronectin adsorption may have only a weak effect on early cellular events of mesenchymal stem cells (MSCs) at least in the case of the nanostructured Ti implant surface incorporating Sr. Moreover, results indicate that Sr overrides the effect of Ca and other important surface factors (i.e., surface area and wettability) in the osteogenesis function of various MSCs (derived from human adipose, bone marrow, and murine bone marrow). In addition, surface engineering of nanostructured Ti implants using Sr ions is expected to exert additional beneficial effects on implant bone healing through the proper balancing of the allocation of MSCs between adipogenesis and osteogenesis. This work provides insight into the future surface design of Ti dental implants using surface bioactive ion chemistry and nanotopography.

  17. Modification of polyvinyl alcohol surface properties by ion implantation

    NASA Astrophysics Data System (ADS)

    Pukhova, I. V.; Kurzina, I. A.; Savkin, K. P.; Laput, O. A.; Oks, E. M.

    2017-05-01

    We describe our investigations of the surface physicochemical properties of polyvinyl alcohol modified by silver, argon and carbon ion implantation to doses of 1 × 1014, 1 × 1015 and 1 × 1016 ion/cm2 and energies of 20 keV (for C and Ar) and 40 keV (for Ag). Infrared spectroscopy (IRS) indicates that destructive processes accompanied by chemical bond (sbnd Cdbnd O) generation are induced by implantation, and X-ray photoelectron spectroscopy (XPS) analysis indicates that the implanted silver is in a metallic Ag3d state without stable chemical bond formation with polymer chains. Ion implantation is found to affect the surface energy: the polar component increases while the dispersion part decreases with increasing implantation dose. Surface roughness is greater after ion implantation and the hydrophobicity increases with increasing dose, for all ion species. We find that ion implantation of Ag, Ar and C leads to a reduction in the polymer microhardness by a factor of five, while the surface electrical resistivity declines modestly.

  18. Ion Implanted GaAs I.C. Process Technology

    DTIC Science & Technology

    1981-07-01

    in ion implantation in GaAs, coupled with better control of the substrate material. 1 Once ion implantation became a reliable processing technology it... Processing Technology for Planar GaAs Integrated Circuits," GaAs IC Symposium, Lake Tahoe, CA., Sept. 1979. 20. R.C. Eden, "GaAs Integrated Circuit Device...1980. 25. B.M. Welch, "Advances in GaAs LSI!VLSI Processing Technology ," Sol. St. Tech., Feb. 1980, pp. 95-101. 27. R. Zucca, B.M. Welch, P.M

  19. Wear analysis and finishing of bioceramic implant surfaces.

    PubMed

    Denkena, Berend; Reichstein, Martin; van der Meer, Marijke; Ostermeier, Sven; Hurschler, Christof

    2008-01-01

    A primary cause for revision operations of joint replacements is the implant loosening, due to immune reactions resulting from the agglomeration of polyethylene wear debris. Motivated by the successful application of bioceramic materials in hip joint prostheses, a trend towards the development of hard implant materials has occurred. Nonetheless in the area of total knee arthroplasty (TKA), modern efforts have still utilized polyethylene as the tibial-inlay joint component. The use of bioceramic hard-hard-pairings for total knee arthroplasty has been prevented by the complex kinematics and geometries required. Ceramics cannot cope with non-uniform loads, which suggests the need for new designs appropriate to the material. Furthermore, biomechanical requirements should be considered. A rolling-gliding wear simulator, which reproduces the movements and stresses of the knee joint on specimens of simplified geometry, has therefore been developed. High-precision machining processes for free formed bioceramic surfaces, with suitable grinding and polishing tools which adjust to constantly changing contact conditions, are essential. The goal is to put automated finishing in one clamping with five simultaneous controlled axes into practice. The developed manufacturing technologies will allow the advantageous bioceramic materials to be applied and accepted for more complex joint replacements such as knee prostheses.

  20. Amplification, Technology, and Cochlear Implants for Infants.

    ERIC Educational Resources Information Center

    Adam, Arlie J.

    1993-01-01

    Early amplification is crucial to efficient habilitation and development of oral communication skills in hearing-impaired infants. Initial evaluation and fitting of amplification is a joint effort by the audiologist, therapist, and parents, whether the child uses traditional hearing aids or cochlear implants, and should be supplemented by a…

  1. Assessment of CpTi Surface Properties after Nitrogen Ion Implantation with Various Doses and Energies

    NASA Astrophysics Data System (ADS)

    Fulazzaky, Mohamad Ali; Ali, Nurdin; Samekto, Haryanti; Ghazali, Mohd Imran

    2012-11-01

    Nitrogen ion implantation is one of the surface modification techniques used for increasing corrosion resistance of commercially pure titanium (CpTi). The nitrogen ion implanted CpTi in various doses markedly changes the corrosion resistance. Still the effect of nitrogen ion implantation on the CpTi at different energies needs to be verified. This study uses different methods to assess the CpTi surface properties after nitrogen ion implantation in various doses and energy. Surface hardness of the CpTi increases with an increase of the dose and decreases with an increase of the energy. The precipitation of the TiN increases with an increase of the nitrogen dose, and no formation of the Ti2N phase clearly appears. Corrosion resistance of the CpTi specimens can be upgraded to some extent after their surfaces are modified, implanting nitrogen ions at 100 keV by increasing dose. The optimum surface properties of the implanted CpTi are analyzed to contribute to materials science technology.

  2. Study on application of aerospace technology to improve surgical implants

    NASA Technical Reports Server (NTRS)

    Johnson, R. E.; Youngblood, J. L.

    1982-01-01

    The areas where aerospace technology could be used to improve the reliability and performance of metallic, orthopedic implants was assessed. Specifically, comparisons were made of material controls, design approaches, analytical methods and inspection approaches being used in the implant industry with hardware for the aerospace industries. Several areas for possible improvement were noted such as increased use of finite element stress analysis and fracture control programs on devices where the needs exist for maximum reliability and high structural performance.

  3. Digital technologies for dental implant treatment planning and guided surgery.

    PubMed

    Greenberg, Alex M

    2015-05-01

    Oral and maxillofacial surgeons now have extraordinary imaging, software planning, and guide fabrication technologies at their disposal to aid in their case selection, clinical decision making, and surgical procedures for dental implant placement. Cone beam CT has opened a new era of office-based diagnostic capability and responsibility. Improved clinical experiences and evidence-based superior outcomes can be provided with confidence to patients when CT-guided dental implant surgery is used. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. HISTOMORPHOMETRIC ANALYSIS OF PURE TITANIUM IMPLANTS WITH POROUS SURFACE VERSUS ROUGH SURFACE

    PubMed Central

    Brentel, Aline Scalone; de Vasconcellos, Luana Marotta Reis; Oliveira, Marize Varella; Graça, Mário Lima de Alencastro; de Vasconcellos, Luis Gustavo Oliveira; Cairo, Carlos Alberto Alves; Carvalho, Yasmin Rodarte

    2006-01-01

    The purpose of this study was to analyze the bone repair around commercially pure titanium implants with rough and porous surface, fabricated using powder metallurgy technique, after their insertion in tibiae of rabbits. Seven male rabbits were used. Each animal received 3 porous-surface implants in the left tibia and 3 rough-surface implants in the right tibia. The rabbits were sacrificed 4 weeks after surgery and fragments of the tibiae containing the implants were submitted to histological and histomorphometric analyses to evaluate new bone formation at the implant-bone interface. Means (%) of bone neoformation obtained in the histomorphometric analysis were compared by Student's t-test for paired samples at 5% significance level.. The results of the histological analysis showed that osseointegration occurred for both types of implants with similar quality of bone tissue. The histomorphometric analysis revealed means of new bone formation at implant-bone interface of 79.69 ± 1.00% and 65.05 ± 1.23% for the porous- and rough-surface implants, respectively. Statistically significant difference was observed between the two types of implants with respect to the amount new bone formation (p<0.05). In conclusion, the porous-surface implants contributed to the osseointegration because they provide a larger contact area at implant-bone interface. PMID:19089076

  5. Controlled implant/soft tissue interaction by nanoscale surface modifications of 3D porous titanium implants.

    PubMed

    Rieger, Elisabeth; Dupret-Bories, Agnès; Salou, Laetitia; Metz-Boutigue, Marie-Helene; Layrolle, Pierre; Debry, Christian; Lavalle, Philippe; Vrana, Nihal Engin

    2015-06-07

    Porous titanium implants are widely employed in the orthopaedics field to ensure good bone fixation. Recently, the use of porous titanium implants has also been investigated in artificial larynx development in a clinical setting. Such uses necessitate a better understanding of the interaction of soft tissues with porous titanium structures. Moreover, surface treatments of titanium have been generally evaluated in planar structures, while the porous titanium implants have complex 3 dimensional (3D) architectures. In this study, the determining factors for soft tissue integration of 3D porous titanium implants were investigated as a function of surface treatments via quantification of the interaction of serum proteins and cells with single titanium microbeads (300-500 μm in diameter). Samples were either acid etched or nanostructured by anodization. When the samples are used in 3D configuration (porous titanium discs of 2 mm thickness) in vivo (in subcutis of rats for 2 weeks), a better integration was observed for both anodized and acid etched samples compared to the non-treated implants. If the implants were also pre-treated with rat serum before implantation, the integration was further facilitated. In order to understand the underlying reasons for this effect, human fibroblast cell culture tests under several conditions (directly on beads, beads in suspension, beads encapsulated in gelatin hydrogels) were conducted to mimic the different interactions of cells with Ti implants in vivo. Physical characterization showed that surface treatments increased hydrophilicity, protein adsorption and roughness. Surface treatments also resulted in improved adsorption of serum albumin which in turn facilitated the adsorption of other proteins such as apolipoprotein as quantified by protein sequencing. The cellular response to the beads showed considerable difference with respect to the cell culture configuration. When the titanium microbeads were entrapped in cell

  6. A Brief Historical Perspective on Dental Implants, Their Surface Coatings and Treatments

    PubMed Central

    Abraham, Celeste M

    2014-01-01

    This review highlights a brief, chronological sequence of the history of dental implants. This historical perspective begins with ancient civilizations and spotlights predominant dentists and their contributions to implant development through time. The physical, chemical and biologic properties of various dental implant surfaces and coatings are discussed, and specific surface treatments include an overview of machined implants, etched implants, and sand-blasted implants. Dental implant coatings such as hydroxyapatite, fluoride, and statin usage are further reviewed. PMID:24894638

  7. Application of nitrogen plasma immersion ion implantation to titanium nasal implants with nanonetwork surface structure

    SciTech Connect

    Sun, Ying-Sui; Yang, Wei-En; Zhang, Lan; Zhu, Hongqin; Lan, Ming-Ying; Lee, Sheng-Wei; Huang, Her-Hsiung

    2016-07-15

    In nasal reconstruction, the response of cells to titanium (Ti) implants is mainly determined by surface features of the implant. In a pilot study, the authors applied electrochemical anodization to Ti surfaces in an alkaline solution to create a network of nanoscale surface structures. This nanonetwork was intended to enhance the responses of primary human nasal epithelial cell (HNEpC) to the Ti surface. In this study, the authors then treated the anodized, nanonetwork-structured Ti surface using nitrogen plasma immersion ion implantation (NPIII) in order to further improve the HNEpC response to the Ti surface. Subsequently, surface characterization was performed to elucidate morphology, roughness, wettability, and chemistry of specimens. Cytotoxicity, blood, and HNEpC responses were also evaluated. Our results demonstrate that NPIII treatment led to the formation of a noncytotoxic TiN-containing thin film (thickness <100 nm) on the electrochemically anodized Ti surface with a nanonetwork-structure. NPIII treatment was shown to improve blood clotting and the adhesion of platelets to the anodized Ti surface as well as the adhesion and proliferation of hNEpC. This research spreads our understanding of the fact that a TiN-containing thin film, produced using NPIII treatment, could be used to improve blood and HNEpC responses to anodized, nanonetwork-structured Ti surfaces in nasal implant applications.

  8. Status of surface modification techniques for artificial hip implants

    PubMed Central

    Ghosh, Subir; Abanteriba, Sylvester

    2016-01-01

    Abstract Surface modification techniques have been developed significantly in the last couple of decades for enhanced tribological performance of artificial hip implants. Surface modification techniques improve biological, chemical and mechanical properties of implant surfaces. Some of the most effective techniques, namely surface texturing, surface coating, and surface grafting, are applied to reduce the friction and wear of artificial implants. This article reviews the status of the developments of surface modification techniques and their effects on commonly used artificial joint implants. This study focused only on artificial hip joint prostheses research of the last 10 years. A total of 27 articles were critically reviewed and categorized according to surface modification technique. The literature reveals that modified surfaces exhibit reduced friction and enhanced wear resistance of the contact surfaces. However, the wear rates are still noticeable in case of surface texturing and surface coating. The associated vortex flow aids to release entrapped wear debris and thus increase the wear particles generation in case of textured surfaces. The earlier delamination of coating materials due to poor adhesion and graphitization transformation has limited the use of coating techniques. Moreover, the produced wear debris has adverse effects on biological fluid. Conversely, the surface grafting technique provides phospholipid like layer that exhibited lower friction and almost zero wear rates even after a longer period of friction and wear test. The findings suggest that further investigations are required to identify the role of surface grafting on film formation and heat resistance ability under physiological hip joint conditions for improved performance and longevity of hip implants. PMID:28228866

  9. Status of surface modification techniques for artificial hip implants.

    PubMed

    Ghosh, Subir; Abanteriba, Sylvester

    2016-01-01

    Surface modification techniques have been developed significantly in the last couple of decades for enhanced tribological performance of artificial hip implants. Surface modification techniques improve biological, chemical and mechanical properties of implant surfaces. Some of the most effective techniques, namely surface texturing, surface coating, and surface grafting, are applied to reduce the friction and wear of artificial implants. This article reviews the status of the developments of surface modification techniques and their effects on commonly used artificial joint implants. This study focused only on artificial hip joint prostheses research of the last 10 years. A total of 27 articles were critically reviewed and categorized according to surface modification technique. The literature reveals that modified surfaces exhibit reduced friction and enhanced wear resistance of the contact surfaces. However, the wear rates are still noticeable in case of surface texturing and surface coating. The associated vortex flow aids to release entrapped wear debris and thus increase the wear particles generation in case of textured surfaces. The earlier delamination of coating materials due to poor adhesion and graphitization transformation has limited the use of coating techniques. Moreover, the produced wear debris has adverse effects on biological fluid. Conversely, the surface grafting technique provides phospholipid like layer that exhibited lower friction and almost zero wear rates even after a longer period of friction and wear test. The findings suggest that further investigations are required to identify the role of surface grafting on film formation and heat resistance ability under physiological hip joint conditions for improved performance and longevity of hip implants.

  10. SURFACE CHEMISTRY INFLUENCE IMPLANT MEDIATED HOST TISSUE RESPONSES

    PubMed Central

    Kamath, Shwetha; Bhattacharyya, Dhiman; Padukudru, Chandana; Timmons, Richard B.; Tang, Liping

    2011-01-01

    Implant-mediated fibrotic reactions are detrimental to the performance of encapsulated cells, implanted drug release devices and sensors. To improve the implant function and longevity, research has emphasized altering cellular responses. Although material surface functional groups have been shown to be potent in affecting cellular activity in vitro and short term in vivo responses, these groups appear to have little influence on long-term in vivo fibrotic reactions, possibly as a result of insufficient interactions between recruited host cells and functional groups on the implants. To maximize the influence of functionality on cells, and to mimic drug release microspheres, functionalized micron-sized particles were created and tested for their ability in modulating tissue responses to biomaterial implants. In this work, the surfaces of polypropylene particles were controllably coated with four different functional groups, specifically –OH, -NH2, -CFx and –COOH, using a radio frequency glow discharge plasma polymerization technique. The effect of these surface functionalities on host tissue responses were then evaluated using a mice subcutaneous implantation model. Major differences were observed in contrasting tissue response to the different chemistries. Surfaces with –OH and –NH2 surface groups induced the thickest fibrous capsule accompanied with the greatest cellular infiltration into the implants. In contrast, surfaces with –CFx and –COOH exhibited the least inflammatory/fibrotic responses and cellular infiltrations. The present results clearly demonstrate that, by increasing the available functionalized surface area and spatial distribution, the effect of surface chemistry on tissue reactivity can be substantially enhanced. PMID:18022841

  11. Micro-plasma textured Ti-implant surfaces.

    PubMed

    Beck, U; Lange, R; Neumann, H-G

    2007-02-01

    The surface state of titanium implants modulates bone response and implant anchorage. This evidence brought implant manufacturers to switch from the standard surface refinements and implement new surface treatments for more bone apposition and enhanced interfacial strength measured by removal torque or push-out tests. Anodic plasma-chemical treatment of implant surfaces is a cost-effective process to modify surface topography and chemistry. This technique is used for structuring connected with a coating of implant surfaces. The aim of our investigations, here, is to texture the implant surface in the nanoscale without coating. Ti disks with different mechanical pre-treatment (grinded, glass blasted) were used as substrate. Micro-plasma texturing was carried out in an aqueous electrolyte. By applying a pulsed DC voltage to the specimen, micro-plasma discharge was generated in the thin steam film between immersed specimen and electrolyte. The electrical process parameter current density was varied. The micro-plasma textured Ti surfaces were characterised optically by SEM and electrochemically by CV- (for testing the corrosion parameters), CA- (to give the enlargement of the real surface) and EIS-measurement in range of 100 kHz-100 microHz. We found that the initial structure of the material surface has small or no influence on the results of the micro-plasma treatment. The properties of the thick oxide layer resulting from the plasma process are influenced by electrical process parameters. After removal of the thick oxide layer a fine, micro- and nanoscaled surface structure of the titanium remains.

  12. Modification of anti-bacterial surface properties of textile polymers by vacuum arc ion source implantation

    NASA Astrophysics Data System (ADS)

    Nikolaev, A. G.; Yushkov, G. Yu.; Oks, E. M.; Oztarhan, A.; Akpek, A.; Hames-Kocabas, E.; Urkac, E. S.; Brown, I. G.

    2014-08-01

    Ion implantation provides an important technology for the modification of material surface properties. The vacuum arc ion source is a unique instrument for the generation of intense beams of metal ions as well as gaseous ions, including mixed metal-gas beams with controllable metal:gas ion ratio. Here we describe our exploratory work on the application of vacuum arc ion source-generated ion beams for ion implantation into polymer textile materials for modification of their biological cell compatibility surface properties. We have investigated two specific aspects of cell compatibility: (i) enhancement of the antibacterial characteristics (we chose to use Staphylococcus aureus bacteria) of ion implanted polymer textile fabric, and (ii) the "inverse" concern of enhancement of neural cell growth rate (we chose Rat B-35 neuroblastoma cells) on ion implanted polymer textile. The results of both investigations were positive, with implantation-generated antibacterial efficiency factor up to about 90%, fully comparable to alternative conventional (non-implantation) approaches and with some potentially important advantages over the conventional approach; and with enhancement of neural cell growth rate of up to a factor of 3.5 when grown on suitably implanted polymer textile material.

  13. Development of functional electrical stimulators utilizing cochlear implant technology.

    PubMed

    Davis, R; Patrick, J; Barriskill, A

    2001-01-01

    In 1983, R. Davis proposed the development of a functional electrical stimulator, based on multi-channel cochlear implant technology, for the restoration of function in spinal cord injured paraplegic subjects. In 1984, the US Veteran Administration funded the initial investigations including animal experiments and purchase of a FES stimulator based on the Nucleus 22 cochlear implant. In 1987, the US Food and Drug Administration approved an Investigational Device Exemption (IDE# G870142) for this FES project. In 1991, the first stimulator was implanted in a 21-year old male paraplegic subject (complete thoracic spinal cord lesion at level #10), who was subsequently able to stand and to perform one-handed tasks for up to 1h. In 1996-1997 development started on a new multi-function FES system. In 1998, a stimulator was implanted in a 35-year-old male paraplegic subject (complete thoracic spinal cord lesion at level #10). After 8 months of use providing multiple functions including bladder voiding, the implant's internal antenna wire broke. A modified implant (FES 24-B) is due to be implanted in July 2001.

  14. Atomic force microscopy analysis of different surface treatments of Ti dental implant surfaces

    NASA Astrophysics Data System (ADS)

    Bathomarco, Ti R. V.; Solorzano, G.; Elias, C. N.; Prioli, R.

    2004-06-01

    The surface of commercial unalloyed titanium, used in dental implants, was analyzed by atomic force microscopy. The morphology, roughness, and surface area of the samples, submitted to mechanically-induced erosion, chemical etching and a combination of both, were compared. The results show that surface treatments strongly influence the dental implant physical and chemical properties. An analysis of the length dependence of the implant surface roughness shows that, for scan sizes larger than 50 μm, the average surface roughness is independent of the scanning length and that the surface treatments lead to average surface roughness in the range of 0.37 up to 0.48 μm. It is shown that the implant surface energy is sensitive to the titanium surface area. As the area increases there is a decrease in the surface contact angle.

  15. CAD/CAM technology for implant abutments, crowns, and superstructures.

    PubMed

    Kapos, Theodoros; Evans, Christopher

    2014-01-01

    The aim of this systematic review was to compare implant prostheses fabricated by computer-assisted design and computer-assisted manufacturing (CAD/CAM) with conventionally fabricated implant prostheses when assessing esthetics, complications (biologic and mechanical), patient satisfaction, and economic factors. Electronic searches for clinical studies focusing on long-term follow-up were performed using the PubMed and Ovid search engines. Concentrating on the restorative aspect of the CAD/CAM technology applicable to implant dentistry, pertinent literature was divided into articles related to implant abutments, crowns, and frameworks. A total of 18 articles satisfied the inclusion criteria. Two articles reported on CAD/CAM crowns, six on abutments, and 10 on implant-supported CAD/CAM frameworks. The mean survival rate for CAD/CAM crowns was 98.85% and for CAD/CAM abutments 100%. The mean survival rate for CAD/CAM frameworks was 95.98%. Based on the current literature, CAD/CAM fabricated crowns, abutments, and frameworks demonstrate survival rates comparable to conventionally fabricated prostheses. Implant survival appears unaffected by fabrication technique. Since this technology encompasses several manufacturing variations, a new definition might be necessary to accurately define the processes under which the CAD/CAM restorations are fabricated. "Complete CAD/CAM product" where no or minimal manual intervention is employed could be a possible term.

  16. Mechanical assessment of grit blasting surface treatments of dental implants.

    PubMed

    Shemtov-Yona, K; Rittel, D; Dorogoy, A

    2014-11-01

    This paper investigates the influence of surface preparation treatments of dental implants on their potential (mechanical) fatigue failure, with emphasis on grit-blasting. The investigation includes limited fatigue testing of implants, showing the relationship between fatigue life and surface damage condition. Those observations are corroborated by a detailed failure analysis of retrieved fracture dental implants. In both cases, the negative effect of embedded alumina particles related to the grit-blasting process is identified. The study also comprises a numerical simulation part of the grit blasting process that reveals, for a given implant material and particle size, the existence of a velocity threshold, below which the rough surface is obtained without damage, and beyond which the creation of significant surface damage will severely reduce the fatigue life, thus increasing fracture probability. The main outcome of this work is that the overall performance of dental implants comprises, in addition to the biological considerations, mechanical reliability aspects. Fatigue fracture is a central issue, and this study shows that uncontrolled surface roughening grit-blasting treatments can induce significant surface damage which accelerate fatigue fracture under certain conditions, even if those treatments are beneficial to the osseointegration process. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Conducting shrinkable nanocomposite based on au-nanoparticle implanted plastic sheet: tunable thermally induced surface wrinkling.

    PubMed

    Greco, Francesco; Bellacicca, Andrea; Gemmi, Mauro; Cappello, Valentina; Mattoli, Virgilio; Milani, Paolo

    2015-04-08

    A thermally shrinkable and conductive nanocomposite material is prepared by supersonic cluster beam implantation (SCBI) of neutral Au nanoparticles (Au NPs) into a commercially available thermo-retractable polystyrene (PS) sheet. Micronanowrinkling is obtained during shrinking, which is studied by means of SEM, TEM and AFM imaging. Characteristic periodicity is determined and correlated with nanoparticle implantation dose, which permits us to tune the topographic pattern. Remarkable differences emerged with respect to the well-known case of wrinkling of bilayer metal-polymer. Wrinkled composite surfaces are characterized by a peculiar multiscale structuring that promises potential technological applications in the field of catalytic surfaces, sensors, biointerfaces, and optics, among others.

  18. Advances in the surface modification techniques of bone-related implants for last 10 years

    PubMed Central

    Qiu, Zhi-Ye; Chen, Cen; Wang, Xiu-Mei; Lee, In-Seop

    2014-01-01

    At the time of implanting bone-related implants into human body, a variety of biological responses to the material surface occur with respect to surface chemistry and physical state. The commonly used biomaterials (e.g. titanium and its alloy, Co–Cr alloy, stainless steel, polyetheretherketone, ultra-high molecular weight polyethylene and various calcium phosphates) have many drawbacks such as lack of biocompatibility and improper mechanical properties. As surface modification is very promising technology to overcome such problems, a variety of surface modification techniques have been being investigated. This review paper covers recent advances in surface modification techniques of bone-related materials including physicochemical coating, radiation grafting, plasma surface engineering, ion beam processing and surface patterning techniques. The contents are organized with different types of techniques to applicable materials, and typical examples are also described. PMID:26816626

  19. Surface Passivation and Junction Formation Using Low Energy Hydrogen Implants

    NASA Technical Reports Server (NTRS)

    Fonash, S. J.

    1985-01-01

    New applications for high current, low energy hydrogen ion implants on single crystal and polycrystal silicon grain boundaries are discussed. The effects of low energy hydrogen ion beams on crystalline Si surfaces are considered. The effect of these beams on bulk defects in crystalline Si is addressed. Specific applications of H+ implants to crystalline Si processing are discussed. In all of the situations reported on, the hydrogen beams were produced using a high current Kaufman ion source.

  20. Surface acoustic wave probe implant for predicting epileptic seizures

    DOEpatents

    Gopalsami, Nachappa [Naperville, IL; Kulikov, Stanislav [Sarov, RU; Osorio, Ivan [Leawood, KS; Raptis, Apostolos C [Downers Grove, IL

    2012-04-24

    A system and method for predicting and avoiding a seizure in a patient. The system and method includes use of an implanted surface acoustic wave probe and coupled RF antenna to monitor temperature of the patient's brain, critical changes in the temperature characteristic of a precursor to the seizure. The system can activate an implanted cooling unit which can avoid or minimize a seizure in the patient.

  1. Comparison of surface modified zirconia implants with commercially available zirconium and titanium implants: a histological study in pigs.

    PubMed

    Gredes, Tomasz; Kubasiewicz-Ross, Pawel; Gedrange, Tomasz; Dominiak, Marzena; Kunert-Keil, Christiane

    2014-08-01

    New biomaterials and their various surface modifications should undergo in vitro and in vivo evaluation before clinical trials. The objective of our in vivo study was to evaluate the biocompatibility of newly created zirconium implant surfaces after implantation in the lower jaw of pigs and compare the osseointegration of these dental implants with commercially available zirconium and titanium implants. After a healing period of 12 weeks, a histological analysis of the soft and hard tissues and a histomorphometric analysis of the bone-implant contact (BIC) were performed. The implant surfaces showed an intimate connection to the adjacent bone for all tested implants. The 3 newly created zirconium implant surfaces achieved a BIC of 45% on average in comparison with a BIC of 56% from the reference zirconium implants and 35% from titanium implants. Furthermore, the new zirconium implants had a better attachment to gingival and bone tissues in the range of implant necks as compared with the reference implants. The results suggest that the new implants comparably osseointegrate within the healing period, and they have a good in vivo biocompatibility.

  2. Evaluating the Feasibility of Using Remote Technology for Cochlear Implants.

    PubMed

    Goehring, Jenny L; Hughes, Michelle L; Baudhuin, Jacquelyn L

    2012-01-01

    The use of remote technology to provide cochlear implant services has gained popularity in recent years. This article contains a review of research evaluating the feasibility of remote service delivery for recipients of cochlear implants. To date, published studies have determined that speech-processor programming levels and other objective tests (electrode impedance and electrically evoked compound action potentials) are equivalent to those obtained in the face-to-face condition. Despite these promising findings, speech perception using remote technology has proven to be more challenging. Previous investigations have evaluated speech perception with recipients of cochlear implants using videoconference (Polycom) equipment in nonsound-treated rooms (due to lack of access to audiological sound booths in rural areas). Results have revealed poorer speech perception scores using remote technology compared to face-to-face results. Additionally, it has been shown that Polycom transmission of a speech stimulus does not cause significant compression for adequate evaluation; rather, poorer results are due to testing performed in nonsound-treated environments. Based on the literature, telepractice is a feasible option for cochlear implant service delivery. Barriers to the wide-spread use of remote services for recipients of cochlear implants include a uniform system for the evaluation of speech perception, validation of services for pediatric recipients and initial activations, license reciprocity, and reimbursement for services.

  3. Controlled implant/soft tissue interaction by nanoscale surface modifications of 3D porous titanium implants

    NASA Astrophysics Data System (ADS)

    Rieger, Elisabeth; Dupret-Bories, Agnès; Salou, Laetitia; Metz-Boutigue, Marie-Helene; Layrolle, Pierre; Debry, Christian; Lavalle, Philippe; Engin Vrana, Nihal

    2015-05-01

    Porous titanium implants are widely employed in the orthopaedics field to ensure good bone fixation. Recently, the use of porous titanium implants has also been investigated in artificial larynx development in a clinical setting. Such uses necessitate a better understanding of the interaction of soft tissues with porous titanium structures. Moreover, surface treatments of titanium have been generally evaluated in planar structures, while the porous titanium implants have complex 3 dimensional (3D) architectures. In this study, the determining factors for soft tissue integration of 3D porous titanium implants were investigated as a function of surface treatments via quantification of the interaction of serum proteins and cells with single titanium microbeads (300-500 μm in diameter). Samples were either acid etched or nanostructured by anodization. When the samples are used in 3D configuration (porous titanium discs of 2 mm thickness) in vivo (in subcutis of rats for 2 weeks), a better integration was observed for both anodized and acid etched samples compared to the non-treated implants. If the implants were also pre-treated with rat serum before implantation, the integration was further facilitated. In order to understand the underlying reasons for this effect, human fibroblast cell culture tests under several conditions (directly on beads, beads in suspension, beads encapsulated in gelatin hydrogels) were conducted to mimic the different interactions of cells with Ti implants in vivo. Physical characterization showed that surface treatments increased hydrophilicity, protein adsorption and roughness. Surface treatments also resulted in improved adsorption of serum albumin which in turn facilitated the adsorption of other proteins such as apolipoprotein as quantified by protein sequencing. The cellular response to the beads showed considerable difference with respect to the cell culture configuration. When the titanium microbeads were entrapped in cell

  4. Modified implant surface with slower and less initial biofilm formation.

    PubMed

    John, Gordon; Becker, Jürgen; Schwarz, Frank

    2015-06-01

    Peri-implant mucositis and peri-implantitis are a raising issue in dental implantology. Peri-implant infections are mainly caused by the formation of biofilm. Different surface textures exhibit various conditions for biofilm formation resulting in several speed of maturation and development. On three different titanium implant surfaces, machined-surface (M), sandblasted large grit, and acid-etched surface (SLA) and machined-modified acid-etched surface (mod MA) initial biofilms were collected. Plaque formation was investigated by erythrosine staining and energy-dispersive X-ray spectroscopy (EDX). For testing the biocompatibility of these plaque-settled surfaces, autoclaved specimens were settled with human gingival fibroblasts, and cell viability was tested. The mean initial plaque surface was detected in the following descending order: M > SLA > mod MA. The differences between these groups were significant. The highest cell viability was detected in the M groups, whereas mod MA and SLA showed comparable results. The results of initial biofilm formation were proved by EDX. Within the limitations of this study, conclusion can be made that mod MA surface shows significant slower initial biofilm formation which could be an advantage in initial transgingival healing process and also an easement for oral hygiene of patients because maturation of plaque is retarded, and immature biofilms are easier to remove. © 2013 Wiley Periodicals, Inc.

  5. Adherent endotoxin on dental implant surfaces: a reappraisal.

    PubMed

    Morra, Marco; Cassinelli, Clara; Bollati, Daniele; Cascardo, Giovanna; Bellanda, Marco

    2015-02-01

    Osteoimmunology is the crosstalk between cells from the immune and skeletal systems, suggesting a role of pro-inflammatory cytokines in the stimulation of osteoclast activity. Endotoxin or bacterial challenges to inflammatory cells are directly relevant to dental implant pathologies involving bone resorption, such as osseointegration failure and peri-implantitis. While the endotoxin amount on implant devices is regulated by standards, it is unknown whether commercially available dental implants elicit different levels of adherent-endotoxin stimulated cytokines. The objective of this work is to develop a model system and evaluate endotoxin-induced expression of pro-inflammatory cytokine genes relevant to osteoclast activation on commercially available dental implants. Murine J774-A1 macrophages were cultured on Ti disks with different level of lipopolysaccharide (LPS) contamination to define the time-course of the inflammatory response to endotoxin, as evaluated by reverse transcription polymerase chain reaction analysis. The developed protocol was then used to measure adherent endotoxin on commercially available packaged and sterile dental implants in the "as-implanted" condition. Results show that tested dental implants induce variable expression of endotoxin-stimulated genes, sometimes above the level expected to promote bone resorption in vivo. Results are unaffected by the specific surface treatment; rather, they likely reflect care in cleaning and packaging protocols. In conclusion, expression of genes that enhance osteoclast activity through endotoxin stimulation of inflammatory cells is widely different on commercially available dental implants. A reappraisal of the clinical impact of adherent endotoxins on dental (and bone) implant devices is required in light of increasing knowledge on crosstalk between cells from the immune and skeletal systems.

  6. Using stereophotogrammetric technology for obtaining intraoral digital impressions of implants.

    PubMed

    Pradíes, Guillermo; Ferreiroa, Alberto; Özcan, Mutlu; Giménez, Beatriz; Martínez-Rus, Francisco

    2014-04-01

    The procedure for making impressions of multiple implants continues to be a challenge, despite the various techniques proposed to date. The authors' objective in this case report is to describe a novel digital impression method for multiple implants involving the use of stereophotogrammetric technology. The authors present three cases of patients who had multiple implants in which the impressions were obtained with this technology. Initially, a stereo camera with an infrared flash detects the position of special flag abutments screwed into the implants. This process is based on registering the x, y and z coordinates of each implant and the distances between them. This information is converted into a stereolithographic (STL) file. To add the soft-tissue information, the user must obtain another STL file by using an intraoral or extraoral scanner. In the first case presented, this information was acquired from the plaster model with an extraoral scanner; in the second case, from a Digital Imaging and Communication in Medicine (DICOM) file of the plaster model obtained with cone-beam computed tomography; and in the third case, through an intraoral digital impression with a confocal scanner. In the three cases, the frameworks manufactured from this technique showed a correct clinical passive fit. At follow-up appointments held six, 12 and 24 months after insertion of the prosthesis, no complications were reported. Stereophotogrammetric technology is a viable, accurate and easy technique for making multiple implant impressions. Clinicians can use stereophotogrammetric technology to acquire reliable digital master models as a first step in producing frameworks with a correct passive fit.

  7. Ion Implantation Studies of Titanium Metal Surfaces.

    DTIC Science & Technology

    1981-01-01

    Lorenzelli and R. Pascard, Compt. Rend. 259, (1964) 2442-2444. 8. Linus Pauling , The Nature of the Chemical Bond, pg. 92 (Cornell Univ. Press, Ithaca...K. Hirvonen. 3. S. Spooner and K. 0. Legg,lon Implantation Metallurgy, 162 (1980); ed. C. M. Preece and J. K. Hirvonen. 4. L. Pauling , The Nature of...R from the Pauling electronegativity scale. According to Pauling (8), the contribu- tion of the bond to the heat of formation is Q - 23 (YEr - Yc) 2

  8. Biofilm Disrupting Technology for Orthopedic Implants: What’s on the Horizon?

    PubMed Central

    Connaughton, Alexander; Childs, Abby; Dylewski, Stefan; Sabesan, Vani J.

    2014-01-01

    The use of orthopedic implants in joints has revolutionized the treatment of patients with many debilitating chronic musculoskeletal diseases such as osteoarthritis. However, the introduction of foreign material into the human body predisposes the body to infection. The treatment of these infections has become very complicated since the orthopedic implants serve as a surface for multiple species of bacteria to grow at a time into a resistant biofilm layer. This biofilm layer serves as a protectant for the bacterial colonies on the implant making them more resistant and difficult to eradicate when using standard antibiotic treatment. In some cases, the use of antibiotics alone has even made the bacteria more resistant to treatment. Thus, there has been surge in the creation of non-antibiotic anti-biofilm agents to help disrupt the biofilms on the orthopedic implants to help eliminate the infections. In this study, we discuss infections of orthopedic implants in the shoulder then we review the main categories of anti-biofilm agents that have been used for the treatment of infections on orthopedic implants. Then, we introduce some of the newer biofilm disrupting technology that has been studied in the past few years that may advance the treatment options for orthopedic implants in the future. PMID:25705632

  9. Self-organized surface ripple pattern formation by ion implantation

    NASA Astrophysics Data System (ADS)

    Hofsäss, Hans; Zhang, Kun; Bobes, Omar

    2016-10-01

    Ion induced ripple pattern formation on solid surfaces has been extensively studied in the past and the theories describing curvature dependent ion erosion as well as redistribution of recoil atoms have been very successful in explaining many features of the pattern formation. Since most experimental studies use noble gas ion irradiation, the incorporation of the ions into the films is usually neglected. In this work we show that the incorporation or implantation of non-volatile ions also leads to a curvature dependent term in the equation of motion of a surface height profile. The implantation of ions can be interpreted as a negative sputter yield; and therefore, the effect of ion implantation is opposite to the one of ion erosion. For angles up to about 50°, implantation of ions stabilizes the surface, whereas above 50°, ion implantation contributes to the destabilization of the surface. We present simulations of the curvature coefficients using the crater function formalism and we compare the simulation results to the experimental data on the ion induced pattern formation using non-volatile ions. We present several model cases, where the incorporation of ions is a crucial requirement for the pattern formation.

  10. Antimicrobial surfaces for craniofacial implants: state of the art

    PubMed Central

    Actis, Lisa; Gaviria, Laura; Guda, Teja

    2013-01-01

    In an attempt to regain function and aesthetics in the craniofacial region, different biomaterials, including titanium, hydroxyapatite, biodegradable polymers and composites, have been widely used as a result of the loss of craniofacial bone. Although these materials presented favorable success rates, osseointegration and antibacterial properties are often hard to achieve. Although bone-implant interactions are highly dependent on the implant's surface characteristics, infections following traumatic craniofacial injuries are common. As such, poor osseointegration and infections are two of the many causes of implant failure. Further, as increasingly complex dental repairs are attempted, the likelihood of infection in these implants has also been on the rise. For these reasons, the treatment of craniofacial bone defects and dental repairs for long-term success remains a challenge. Various approaches to reduce the rate of infection and improve osseointegration have been investigated. Furthermore, recent and planned tissue engineering developments are aimed at improving the implants' physical and biological properties by improving their surfaces in order to develop craniofacial bone substitutes that will restore, maintain and improve tissue function. In this review, the commonly used biomaterials for craniofacial bone restoration and dental repair, as well as surface modification techniques, antibacterial surfaces and coatings are discussed. PMID:24471018

  11. The evolution of cochlear implant technology and its clinical relevance

    PubMed Central

    Hainarosie, M; Zainea, V; Hainarosie, R

    2014-01-01

    The article presents a brief history of the development of the cochlear implant, from its beginnings to the present day. After a short description of the device, it describes the evolution of the technology for three of the top manufacturing companies, from the first model marketed, to the latest. It presents the technological advancements from one model to the next, taking into account the exterior design, processing capabilities and functionality. PMID:25870662

  12. Surface modification of polymeric materials by plasma immersion ion implantation

    NASA Astrophysics Data System (ADS)

    Fu, Ricky K. Y.; Cheung, I. T. L.; Mei, Y. F.; Shek, C. H.; Siu, G. G.; Chu, Paul K.; Yang, W. M.; Leng, Y. X.; Huang, Y. X.; Tian, X. B.; Yang, S. Q.

    2005-08-01

    Polymer surfaces typically have low surface tension and high chemical inertness and so they usually have poor wetting and adhesion properties. The surface properties can be altered by modifying the molecular structure using plasma immersion ion implantation (PIII). In this work, Nylon-6 was treated using oxygen/nitrogen PIII. The observed improvement in the wettability is due to the oxygenated and nitrogen (amine) functional groups created on the polymer surface by the plasma treatment. X-ray photoelectron spectroscopy (XPS) results show that nitrogen and oxygen plasma implantation result in C-C bond breaking to form the imine and amine groups as well as alcohol and/or carbonyl groups on the surface. The water contact angle results reveal that the surface wetting properties depend on the functional groups, which can be adjusted by the ratio of oxygen-nitrogen mixtures.

  13. Cellular responses evoked by different surface characteristics of intraosseous titanium implants.

    PubMed

    Feller, Liviu; Jadwat, Yusuf; Khammissa, Razia A G; Meyerov, Robin; Schechter, Israel; Lemmer, Johan

    2015-01-01

    The properties of biomaterials, including their surface microstructural topography and their surface chemistry or surface energy/wettability, affect cellular responses such as cell adhesion, proliferation, and migration. The nanotopography of moderately rough implant surfaces enhances the production of biological mediators in the peri-implant microenvironment with consequent recruitment of differentiating osteogenic cells to the implant surface and stimulates osteogenic maturation. Implant surfaces with moderately rough topography and with high surface energy promote osteogenesis, increase the ratio of bone-to-implant contact, and increase the bonding strength of the bone to the implant at the interface. Certain features of implant surface chemistry are also important in enhancing peri-implant bone wound healing. It is the purpose of this paper to review some of the more important features of titanium implant surfaces which have an impact on osseointegration.

  14. Cryogenic ion implantation near amorphization threshold dose for halo/extension junction improvement in sub-30 nm device technologies

    NASA Astrophysics Data System (ADS)

    Park, Hugh; Todorov, Stan; Colombeau, Benjamin; Rodier, Dennis; Kouzminov, Dimitry; Zou, Wei; Guo, Baonian; Khasgiwale, Niranjan; Decker-Lucke, Kurt

    2012-11-01

    We report on junction advantages of cryogenic ion implantation with medium current implanters. We propose a methodical approach on maximizing cryogenic effects on junction characteristics near the amorphization threshold doses that are typically used for halo implants for sub-30 nm technologies. BF2+ implant at a dose of 8×1013cm-2 does not amorphize silicon at room temperature. When implanted at -100°C, it forms a 30 - 35 nm thick amorphous layer. The cryogenic BF2+ implant significantly reduces the depth of the boron distribution, both as-implanted and after anneals, which improves short channel rolloff characteristics. It also creates a shallower n+-p junction by steepening profiles of arsenic that is subsequently implanted in the surface region. We demonstrate effects of implant sequences, germanium preamorphization, indium and carbon co-implants for extension/halo process integration. When applied to sequences such as Ge+As+C+In+BF2+, the cryogenic implants at -100°C enable removal of Ge preamorphization, and form more active n+-p junctions and steeper B and In halo profiles than sequences at room temperature.

  15. Cryogenic ion implantation near amorphization threshold dose for halo/extension junction improvement in sub-30 nm device technologies

    SciTech Connect

    Park, Hugh; Todorov, Stan; Colombeau, Benjamin; Rodier, Dennis; Kouzminov, Dimitry; Zou Wei; Guo Baonian; Khasgiwale, Niranjan; Decker-Lucke, Kurt

    2012-11-06

    We report on junction advantages of cryogenic ion implantation with medium current implanters. We propose a methodical approach on maximizing cryogenic effects on junction characteristics near the amorphization threshold doses that are typically used for halo implants for sub-30 nm technologies. BF{sub 2}{sup +} implant at a dose of 8 Multiplication-Sign 10{sup 13}cm{sup -2} does not amorphize silicon at room temperature. When implanted at -100 Degree-Sign C, it forms a 30 - 35 nm thick amorphous layer. The cryogenic BF{sub 2}{sup +} implant significantly reduces the depth of the boron distribution, both as-implanted and after anneals, which improves short channel rolloff characteristics. It also creates a shallower n{sup +}-p junction by steepening profiles of arsenic that is subsequently implanted in the surface region. We demonstrate effects of implant sequences, germanium preamorphization, indium and carbon co-implants for extension/halo process integration. When applied to sequences such as Ge+As+C+In+BF{sub 2}{sup +}, the cryogenic implants at -100 Degree-Sign C enable removal of Ge preamorphization, and form more active n{sup +}-p junctions and steeper B and In halo profiles than sequences at room temperature.

  16. Bacterial inactivation/sterilization by argon plasma treatment on contaminated titanium implant surfaces: In vitro study.

    PubMed

    Annunziata, Marco; Canullo, Luigi; Donnarumma, Giovanna; Caputo, Pina; Nastri, Livia; Guida, Luigi

    2016-01-01

    Surface treatment by argon plasma is widely used as the last step of the manufacturing process of titanium implant fixtures before their sterilization by gamma rays. The possibility of using such a technology in the daily clinical practice is particularly fascinating. The aim of the present study was to assess the effects of the argon plasma treatment on different titanium implant surfaces previously exposed in vitro to bacterial contamination. Sterile c.p. titanium implant discs with turned (T, Sa: 0.8μm), sandblasted/acid-etched (SAE, Sa: 1.3μm) and titanium plasma sprayed (TPS, Sa: 3.0μm) surface were used in this study. A strain of Aggregatibacter actinomycetemcomitans ATCC3718 was grown at 37°C under anaerobic conditions for 24 h and then transferred on six discs for each of the three surface types. After 24 hours, a half of the contaminated discs (control group) were directly used to evaluate the colony forming units (CFUs). The other half of the contaminated discs (test group) were treated in an argon plasma chamber for 12 minutes at room temperature prior to be analyzed for CFU counting. All assays were performed using triplicate samples of each material in 3 different experiments. When the CFU counting was carried out on control discs, a total of 1.50x106±1.4x105, 1.55x106±7.07x104 and 3.15x106±2.12x105 CFU was respectively assessed for T, SAE and TPS discs, without statistically significant differences among the three surfaces. On the contrary, any trace of bacterial contamination was assessed for titanium discs treated in the argon plasma chamber prior to be analyzed, irrespectively to the implant surface tested. Within the limit of this study, reported data suggested that the argon plasma technology could be efficiently used to decontaminate/sterilize previously infected titanium implant surfaces.

  17. Ion implantation of graphene-toward IC compatible technologies.

    PubMed

    Bangert, U; Pierce, W; Kepaptsoglou, D M; Ramasse, Q; Zan, R; Gass, M H; Van den Berg, J A; Boothroyd, C B; Amani, J; Hofsäss, H

    2013-10-09

    Doping of graphene via low energy ion implantation could open possibilities for fabrication of nanometer-scale patterned graphene-based devices as well as for graphene functionalization compatible with large-scale integrated semiconductor technology. Using advanced electron microscopy/spectroscopy methods, we show for the first time directly that graphene can be doped with B and N via ion implantation and that the retention is in good agreement with predictions from calculation-based literature values. Atomic resolution high-angle dark field imaging (HAADF) combined with single-atom electron energy loss (EEL) spectroscopy reveals that for sufficiently low implantation energies ions are predominantly substitutionally incorporated into the graphene lattice with a very small fraction residing in defect-related sites.

  18. Spontaneous progression of ligature induced peri-implantitis at implants with different surface roughness: an experimental study in dogs.

    PubMed

    Berglundh, T; Gotfredsen, K; Zitzmann, N U; Lang, N P; Lindhe, J

    2007-10-01

    Peri-implantitis is associated with the presence of submarginal plaque, soft-tissue inflammation and advanced breakdown of the supporting bone. The progression of peri-implantitis following varying periods of continuing plaque accumulation has been studied in animal models. The aim of the current experiment was to study the progression of peri-implantitis around implants with different surface roughness. In five beagle dogs, three implants with either a sandblasted acid-etched surface (SLA) or a polished surface (P) were installed bilaterally in the edentulous premolar regions. After 3 months on a plaque control regimen, experimental peri-implantitis was induced by ligature placement and plaque accumulation was allowed to progress until about 40% of the height of the supporting bone had been lost. After this 4-month period, ligatures were removed and plaque accumulation was continued for an additional 5 months. Radiographs of all implant sites were obtained before and after 'active' experimental peri-implantitis as well as at the end of the experiment. Biopsies were harvested and the tissue samples were prepared for light microscopy. The sections were used for histometric and morphometric examinations. The radiographic examinations indicated that similar amounts of bone loss occurred at SLA and P sites during the active breakdown period, while the progression of bone loss was larger at SLA than at polished sites following ligature removal. The histological examination revealed that both bone loss and the size of the inflammatory lesion in the connective tissue were larger in SLA than in polished implant sites. The area of plaque was also larger at implants with an SLA surface than at implants with a polished surface. It is suggested that the progression of peri-implantitis, if left untreated, is more pronounced at implants with a moderately rough surface than at implants with a polished surface.

  19. Optimal design of composite hip implants using NASA technology

    NASA Technical Reports Server (NTRS)

    Blake, T. A.; Saravanos, D. A.; Davy, D. T.; Waters, S. A.; Hopkins, D. A.

    1993-01-01

    Using an adaptation of NASA software, we have investigated the use of numerical optimization techniques for the shape and material optimization of fiber composite hip implants. The original NASA inhouse codes, were originally developed for the optimization of aerospace structures. The adapted code, which was called OPORIM, couples numerical optimization algorithms with finite element analysis and composite laminate theory to perform design optimization using both shape and material design variables. The external and internal geometry of the implant and the surrounding bone is described with quintic spline curves. This geometric representation is then used to create an equivalent 2-D finite element model of the structure. Using laminate theory and the 3-D geometric information, equivalent stiffnesses are generated for each element of the 2-D finite element model, so that the 3-D stiffness of the structure can be approximated. The geometric information to construct the model of the femur was obtained from a CT scan. A variety of test cases were examined, incorporating several implant constructions and design variable sets. Typically the code was able to produce optimized shape and/or material parameters which substantially reduced stress concentrations in the bone adjacent of the implant. The results indicate that this technology can provide meaningful insight into the design of fiber composite hip implants.

  20. Surface modification by ion implantation and ion beam mixing

    NASA Astrophysics Data System (ADS)

    Rivière, J. P.

    1992-05-01

    After its successful applications in the semiconductor industry, ion implantation is being employed for other technical applications. The main process in ion implantation is the introduction of additive elements to change the composition and properties of the surface region of a material. We present results demonstrating the important improvement of the wear resistance and friction in a NiTi alloy implanted with nitrogen. The formation of hard TiN precipitates embedded in an amorphous layer is responsible for such modifications. The generation of many atomic displacements in collision cascades during implantation can be also employed as a modification process itself. For instance, the chemical disordering in an implanted Fe60Al40 alloy induces a para- to ferromagnetic transition. The formation of an amorphous surface alloy by ion irradiation at a temperature of 15 K has been shown in Ni50Al50 by in situ RBS, channelling and TEM. The new method of dynamic ion mixing (DIM) combines ion bombardment with simultaneous material deposition and allows thicker adherent coatings to be built up, this is shown for both metallic Cu50Ni50 and ceramic TiB2 coatings. Recent results demonstrating a significant increase in fatigue lifetime of a coated 316 L stainless steel are also reported and discussed.

  1. Surface characteristics of implants influence their bone integration after simultaneous placement of implant and GBR membrane.

    PubMed

    Lima, Luiz A; Fuchs-Wehrle, Anita M; Lang, Niklaus P; Hämmerle, Christoph H F; Liberti, Edson; Pompeu, Eduardo; Todescan, José H

    2003-12-01

    The purpose of this study was to evaluate the influence of titanium surface characteristics on bone integration of implants, and to describe the pattern of peri-implant tissue healing after simultaneous implant placement and guided bone regeneration. In four healthy mongrel dogs mandibular premolars were extracted. Two weeks following full mouth prophylaxis and 4 months after extractions, simultaneous membrane and implant surgeries were performed. Efforts were made to produce bony defects with dimensions of 7 x 7 x 7 mm. Into these, 24 standard ITI implants (diameter = 4.1 mm; length = 8 mm) with either a titanium plasma-sprayed (TPS) or a machined surface (MS) were placed. Although implants were inserted 4 mm into cancellous bone, difficulties in achieving optimal primary stability were encountered. All dogs were maintained on a soft diet. Chlorhexidine rinses were performed three times a week. Full mouth prophylaxis was performed every 2 weeks. In the case of membrane exposure, the membranes were removed prematurely (4-6 or 14-15 weeks after surgery). Two dogs were sacrificed at 16 weeks and two at 24 weeks after surgery. Nondecalcified histologic sections were processed and histometric analyses were carried out. When membranes were removed after 4-6 weeks, a vertical bone growth (VB) of 45-61% of the original defect was noted. After membrane removal at 14-15 weeks, similar VB was observed. However, if membranes were left in situ for 24 weeks, VB was between 79% and 96%. In this group of sites, the VB was 66% at 16 weeks and 86% at 24 weeks. Osseointegration in the regenerated bone area ranged from 12% to 32% for the TPS and from 0.0% to 3.6% for the MS implants at 16 and 24 weeks combined. Osseointegration in the pristine host bone area ranged from 16% to 35% for the TPS and from 0.0% to 11% for the MS sites at 16 and 24 weeks. In conclusion, the fraction of implant-bone integration was much higher in the pristine bone compared to that in the regenerated bone

  2. Surface microtopography regulates osteointegration: the role of implant surface microtopography in osteointegration.

    PubMed

    Schwartz, Zvi; Nasazky, Erez; Boyan, Barbara D

    2005-07-01

    Increased surface roughness of dental implants enhances the process of osseointegration. It increases bone conduction and increases BIC in all types of bone, resulting in elevated removal torque values. Surface roughness elevated the CSR of implants implanted in adverse conditions as augmented ridges and sinuses and areas of poor bone, such as the posterior maxilla, and in some cases abolished the deleterious effect of smoking. A growing number of clinical studies suggest that early and immediate loading of rough-surfaced implants may lead to predictable osseointegration. However, it is important to note that these studies provide short-term results based on radiographic observation and clinical mobility only. Before we adopt new surgical and prosthetic guidelines, longer and broader studies are needed. Most recent research has examined the effect of surface roughness on bone healing around implants in vivo and the influence of surface roughness on osteoblasts in vitro. In a study just published, it was found that changing the surface chemistry by submerging an implant in an isotonic sodium chloride solution following acid etching to avoid contamination with molecules from the atmosphere significantly increased osteoblast differentiation in vitro and BIC in vivo. This finding may lead us to a new era in dental implants.

  3. High definition surface micromachining of LiNbO 3 by ion implantation

    NASA Astrophysics Data System (ADS)

    Chiarini, M.; Bentini, G. G.; Bianconi, M.; De Nicola, P.

    2010-10-01

    High Energy Ion Implantation (HEII) of both medium and light mass ions has been successfully applied for the surface micromachining of single crystal LiNbO 3 (LN) substrates. It has been demonstrated that the ion implantation process generates high differential etch rates in the LN implanted areas, when suitable implantation parameters, such as ion species, fluence and energy, are chosen. In particular, when traditional LN etching solutions are applied to suitably ion implanted regions, etch rates values up to three orders of magnitude higher than the typical etching rates of the virgin material, are registered. Further, the enhancement in the etching rate has been observed on x, y and z-cut single crystalline material, and, due to the physical nature of the implantation process, it is expected that it can be equivalently applied also to substrates with different crystallographic orientations. This technique, associated with standard photolithographic technologies, allows to generate in a fast and accurate way very high aspect ratio relief micrometric structures on LN single crystal surface. In this work a description of the developed technology is reported together with some examples of produced micromachined structures: in particular very precisely defined self sustaining suspended structures, such as beams and membranes, generated on LN substrates, are presented. The developed technology opens the way to actual three dimensional micromachining of LN single crystals substrates and, due to the peculiar properties characterising this material, (pyroelectric, electro-optic, acousto-optic, etc.), it allows the design and the production of complex integrated elements, characterised by micrometric features and suitable for the generation of advanced Micro Electro Optical Systems (MEOS).

  4. Assessing the hierarchical structure of titanium implant surfaces.

    PubMed

    Matteson, Jesse L; Greenspan, David C; Tighe, Timothy B; Gilfoy, Nathan; Stapleton, Joshua J

    2016-08-01

    The physical texture of implant surfaces are known to be one important factor in creating a stable bone-implant interface. Simple roughness parameters (for e.g., Sa or Sz) are not entirely adequate when characterizing surfaces possessing hierarchical structure (macro, micro, and nano scales). The aim of this study was to develop an analytical approach to quantify hierarchical surface structure of implant surfaces possessing nearly identical simple roughness. Titanium alloys with macro/micro texture (MM) and macro/micro/nano texture (MMN) were chosen as model surfaces to be evaluated. There was no statistical difference (p > 0.05) in either Sa (13.56 vs. 13.43 µm) or Sz (91.74 vs. 92.39 µm) for the MM and MMN surfaces, respectively. However, when advanced filtering algorithms were applied to these datasets, a statistical difference in roughness was found between MM (Sa = 0.54 µm) and MMN (Sa = 1.06 µm; p < 0.05). Additionally, a method was developed to specifically quantify the density of surface features appearing similar in geometry to natural osteoclastic pits. This analysis revealed a significantly greater numbers of these features (i.e., valleys) on the MMN surface as compared to the MM surface. Finally, atomic force microscopy showed a rougher nano-texture on the MMN surface compared with the MM surface (p < 0.05). The results support recent published studies that show a combination of appropriate micron and nano surface results in a more robust cellular response and increased osteoblast differentiation. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1083-1090, 2016. © 2015 Wiley Periodicals, Inc.

  5. Research and Technology Transfer Ion Implantation Technology for Specialty Materials: Proceedings of a Joint Workshop Held in Knoxville, Tennessee on 26-27 October 1989

    DTIC Science & Technology

    1991-02-01

    Options from the Perspective of a SWall Business, Dr. Ralph B. Alexander, President, Ion Surface Tecnology , Inc. 9:45 &wort MedAniwm for Standards D[vel...implantation technologies, including the technology push /pull issue, psychological issues, competing technologies and relative costs; (2) implementation options...most advantageous method would depend on the specific ap- plication. The issue of technology push /pull, i.e. push from the develo- pers/researchers/ion

  6. Enhancing osseointegration of orthopedic implants with titania nanotube surfaces

    NASA Astrophysics Data System (ADS)

    Baker, Erin A.

    Introduction: As joint arthroplasty surgical procedures increase annually, the development of new strategies, including novel materials and surface modifications, to attain solid bone-implant fixation are needed to increase implant terms of service. In this study, we evaluate two morphologies of titania nanotubes in both in vitro and in vivo experiments to quantify osseointegrative potential and material-level biocompatibility. Materials and Methods: Samples were prepared via an electrochemical etching process. Two different titania nanotube (TiNT) morphologies were produced, Aligned and Trabecular. For the in vitro experiment, Sprague Dawley (SD) rat marrow-derived bone marrow cells (BMC) were seeded on samples. Alkaline phosphatase (ALP) activity, osteocalcin (OC) expression, expression of relevant genes as well as cell attachment and morphology were assessed. In the first in vivo experiment, Kirschner wires were implanted unilaterally into SD rat femora with a TiNT-etched or unmodified (Control) implant. General health assessments and weekly body weights were recorded. At a 12-week endpoint, hematologic, systemic metal ion, and histologic analyses were performed. For the second in vivo experiment, Kirschner wires were implanted bilaterally into SD rat femora, with a TiNT-etched implant in one femora and unmodified (Control) implant as an internal control. At 4- and 12-week endpoints, femora were assessed via biomechanics, undecalcified histology, micro-computed tomography (muCT), and backscattered electron imaging (BEI) to characterize de novo bone formation. Results: In vitro experiments demonstrated BMC attachment and differentiation into osteoblasts as well as greater ALP activity, OC expression, total cell counts, and gene expression (of Col1a1, IGF-1, and osteonectin) on TiNT surfaces versus Controls. Cells on TiNT-etched substrates were smaller in diameter and more eccentric than Controls. In the first in vivo experiment, there were significant differences

  7. Mechanical, chemical and laser treatments of the implant surface in the presence of marginal bone loss around implants.

    PubMed

    Meyle, Joerg

    2012-01-01

    The objective of this review was to summarise current evidence with regard to the decontamination of implant surfaces by mechanical, chemical and physical methods in the presence of marginal bone loss arising from peri-implant infections. A PubMed search identified studies and publications dealing with 'peri-implantitis', 'treatment', 'surface decontamination', 'laser application' 'air-abrasive treatment' and 'photodynamic therapy'. Only studies in international peer-reviewed journals were selected for further evaluation; case reports were not included. Several therapeutic approaches were identified such as mechanical treatment, antiseptics and air-abrasive treatment, photodynamic treatment, and laser applications. Since treatment of infected surfaces with air-powder +/- citric acid, gauze soaked with saline + citric acid or gauze soaked with chlorhexidine led to similar results in experimental studies, cotton pellets with saline may be adequate for cleaning micro-rough surfaces. Antimicrobial photodynamic therapy can effectively reduce the prevalence of pathogens on implant surfaces, but the clinical benefits remain unknown. The increase in temperature of the implant surface caused by the CO2 laser poses a risk. The Er:YAG laser is considered to possess the best properties for implant surface decontamination. In vivo, no single method of surface decontamination (chemical agents, air abrasives or lasers) was found to be superior. In several animal experiments, thorough cleaning of the infected implant surfaces and implantation of these previously infected devices into freshly prepared sites resulted in re-osseointegration, while currently there are no controlled clinical trials where re-osseointegration has been demonstrated in patients. For decontamination of the infected implant surfaces, rinsing with saline (or cleaning with cotton pellets soaked with sterile saline) and air-abrasive treatment seem to work. Laser decontamination of the surface does not improve

  8. Dependence of implantation sequence on surface blistering characteristics due to H and He ions co-implanted in silicon

    NASA Astrophysics Data System (ADS)

    Liang, J. H.; Hsieh, H. Y.; Wu, C. W.; Lin, C. M.

    2015-12-01

    This study investigated surface blistering characteristics due to H and He ions co-implanted in silicon at room temperature. The H and He ion energies were 40 and 50 keV, respectively, so that their depth profiles were similar. The total implantation fluence for the H and He ions was 5 × 1016 cm-2 under various fluence fractions in the H ions. The implantation sequences under investigation were He + H and H + He. Dynamic optical microscopy (DOM) was employed in order to dynamically analyze surface blistering characteristics. This study used DOM data to construct so-called time-temperature-transformation (T-T-T) curves to easily predict blistering and crater transformation at specific annealing times and temperatures. The results revealed that the curves of blister initialization, crater initialization, and crater completion in the He + H implant occurred at a lower annealing temperature but with a longer annealing time compared to those in the H + He implant. Furthermore, the threshold annealing temperatures for blister and crater formation in the He + H implant were lower than they were in the H + He implant. The size distributions of the blisters and craters in the He + H implant extended wider than those in the H + He implant. In addition, the He + H implant exhibited larger blisters and craters compared to the ones in the H + He implant. Since the former has a higher percentage of exfoliation area than the latter, it is regarded as the more optimal implantation sequence.

  9. Interactions between endothelial progenitor cells (EPC) and titanium implant surfaces.

    PubMed

    Ziebart, Thomas; Schnell, Anne; Walter, Christian; Kämmerer, Peer W; Pabst, Andreas; Lehmann, Karl M; Ziebart, Johanna; Klein, Marc O; Al-Nawas, Bilal

    2013-01-01

    Endothelial cells play an important role in peri-implant angiogenesis during early bone formation. Therefore, interactions between endothelial progenitor cells (EPCs) and titanium dental implant surfaces are of crucial interest. The aim of our in vitro study was to investigate the reactions of EPCs in contact with different commercially available implant surfaces. EPCs from buffy coats were isolated by Ficoll density gradient separation. After cell differentiation, EPC were cultured for a period of 7 days on different titanium surfaces. The test surfaces varied in roughness and hydrophilicity: acid-etched (A), sand-blasted-blasted and acid-etched (SLA), hydrophilic A (modA), and hydrophilic SLA (modSLA). Plastic and fibronectin-coated plastic surfaces served as controls. Cell numbers and morphology were analyzed by confocal laser scanning microscopy. Secretion of vascular endothelial growth factor (VEGF)-A was measured by enzyme-linked immunosorbent assay and expressions of iNOS and eNOS were investigated by real-time polymerase chain reaction. Cell numbers were higher in the control groups compared to the cells of titanium surfaces. Initially, hydrophilic titanium surfaces (modA and modSLA) showed lower cell numbers than hydrophobic surfaces (A and SLA). After 7 days smoother surfaces (A and modA) showed increased cell numbers compared to rougher surfaces (SLA and modSLA). Cell morphology of A, modA, and control surfaces was characterized by a multitude of pseudopodia and planar cell soma architecture. SLA and modSLA promoted small and plump cell soma with little quantity of pseudopodia. The lowest VEGF level was measured on A, the highest on modSLA. The highest eNOS and iNOS expressions were found on modA surfaces. The results of this study demonstrate that biological behaviors of EPCs can be influenced by different surfaces. The modSLA surface promotes an undifferentiated phenotype of EPCs that has the ability to secrete growth factors in great quantities. In

  10. Surface modification of SKD-61 steel by ion implantation technique

    SciTech Connect

    Wen, F. L.; Lo, Y.-L.; Yu, Y.-C.

    2007-07-15

    The purpose of this study is to investigate how ion implantation affects the surface characteristics and nitrogenizing depth of the thin film by the use of a NEC 9SDH-2 3 MV Pelletron accelerator that implants nitrogen ions into SKD-61 tool steels for surface modification. Nitrogen ions were implanted into the surface layer of materials so that the hardness of modified films could be improved. Also, the nitride film stripping problems of the traditional nitrogenizing treatment could be overcome by a new approach in surface process engineering. As nitrogen ions with high velocity impacted on the surface of the substrate, the ions were absorbed and accumulated on the surface of the substrate. The experiments were performed with two energies (i.e., 1 and 2 MeV) and different doses (i.e., 2.5x10{sup 15}, 7.5x10{sup 15}, and 1.5x10{sup 16} ions/cm{sup 2}). Nitrogen ions were incorporated into the interface and then diffused through the metal to form a nitride layer. Analysis tools included the calculation of stopping and range of ions in matter (SRIM), the detection of a secondary ion mass spectrometry (SIMS), and nanoindentation testing. Through the depth analysis of SIMS, the effects of the ion-implanted SKD-61 steels after heating at 550 deg. C in a vacuum furnace were examined. The nanoindenting results indicate the variation of hardness of SKD-61 steels with the various ion doses. It reaches two to three times the original hardness of SKD-61 steels.

  11. Nanoscale Surface Modifications of Medical Implants for Cartilage Tissue Repair and Regeneration

    PubMed Central

    Griffin, MF; Szarko, M; Seifailan, A; Butler, PE

    2016-01-01

    Background: Natural cartilage regeneration is limited after trauma or degenerative processes. Due to the clinical challenge of reconstruction of articular cartilage, research into developing biomaterials to support cartilage regeneration have evolved. The structural architecture of composition of the cartilage extracellular matrix (ECM) is vital in guiding cell adhesion, migration and formation of cartilage. Current technologies have tried to mimic the cell’s nanoscale microenvironment to improve implants to improve cartilage tissue repair. Methods: This review evaluates nanoscale techniques used to modify the implant surface for cartilage regeneration. Results: The surface of biomaterial is a vital parameter to guide cell adhesion and consequently allow for the formation of ECM and allow for tissue repair. By providing nanosized cues on the surface in the form of a nanotopography or nanosized molecules, allows for better control of cell behaviour and regeneration of cartilage. Chemical, physical and lithography techniques have all been explored for modifying the nanoscale surface of implants to promote chondrocyte adhesion and ECM formation. Conclusion: Future studies are needed to further establish the optimal nanoscale modification of implants for cartilage tissue regeneration. PMID:28217208

  12. High density interconnection technology - Surface mount technology

    NASA Astrophysics Data System (ADS)

    Menozzi, G.

    The design features of surface mount technology (SMT) circuits for data transmission, engineering and aerospace applications are examined. Details of pin out, dual face, and interconnection techniques employed for SMT circuits mounted on plastic or ceramic leadless chip carriers are explored. The industrial processes applied to obtain the SMT boards are discussed, along with methods for quality assurance, especially for the soldered connections. SMT installations in the form of 4 Mbit multilayer circuits for an ESA project and a 32-bit mainframe computer are described.

  13. The role of implant surface modifications, shape and material on the success of osseointegrated dental implants. A Cochrane systematic review.

    PubMed

    Esposito, Marco; Coulthard, Paul; Thomsen, Peter; Worthington, Helen V

    2005-03-01

    We tested the hypothesis of no difference in implant failures between various dental implant types. We searched for all randomised clinical trials comparing different implant types/systems with a follow up of at least one year on four databases. Screening of eligible trials, quality assessment and data extraction were conducted in duplicate. Thirty-one trials were identified. Twelve trials, reporting results of 512 patients, were included. No significant differences were observed for implant failures. There were minor statistically significant differences for peri-implant bone level changes. Turned surfaces had a 20% reduction in risk of being affected by perimplantitis over a 3-year period.

  14. Surface microanalytical studies of nitrogen ion-implanted steel

    NASA Astrophysics Data System (ADS)

    Dodd, Charles G.; Meeker, G. P.; Baumann, Scott M.; Norberg, James C.; Legg, Keith O.

    1985-03-01

    Five types of industrial steels, 1018, 52100, M-2, 440C, and 304 were ion implanted with nitrogen and subjected to surface microanalysis by three independent surface techniques: AES, RBS, and SIMS. The results provided understanding for earlier observations of the properties of various types of steel after nitrogen implantation. The steels that retained the most nitrogen and that have been reported to benefit the most in improved tribological properties from ion implantation were ferritic carbon and austenitic stainless steels, such as soft 1018 and 304, respectively. Heat-treated martensitic carbon steels such as 52100 and M-2 tool steel were found to retain the least nitrogen, and they have been reported to benefit less from nitrogen implantation; however, the interaction of transition metal carbides in M-2 with nitrogen has not been clarified. The data showed that 440C steel retained as much nitrogen as 1018 and 304, but treatment benefits may be limited to improvements in properties related to toughness and impact resistance.

  15. Adhesion of osteoblasts to a nanorough titanium implant surface

    PubMed Central

    Gongadze, Ekaterina; Kabaso, Doron; Bauer, Sebastian; Slivnik, Tomaž; Schmuki, Patrik; van Rienen, Ursula; Iglič, Aleš

    2011-01-01

    This work considers the adhesion of cells to a nanorough titanium implant surface with sharp edges. The basic assumption was that the attraction between the negatively charged titanium surface and a negatively charged osteoblast is mediated by charged proteins with a distinctive quadrupolar internal charge distribution. Similarly, cation-mediated attraction between fibronectin molecules and the titanium surface is expected to be more efficient for a high surface charge density, resulting in facilitated integrin mediated osteoblast adhesion. We suggest that osteoblasts are most strongly bound along the sharp convex edges or spikes of nanorough titanium surfaces where the magnitude of the negative surface charge density is the highest. It is therefore plausible that nanorough regions of titanium surfaces with sharp edges and spikes promote the adhesion of osteoblasts. PMID:21931478

  16. High Density Ion Implanted Contiguous Disk Bubble Technology.

    DTIC Science & Technology

    1987-10-31

    wall motion Depending on the type of device being studied, the forces in (1) may arise from externally applied fields, permalloy propagation elements...the applied bias field, 2) the charged wall, 3) the edge- affinity due to the implanted/unimplanted boundary and, 4) conductors used to activate...c, H and H denote the Z components of the applied .V . 6 " field and the demagnetizing field originating from surface pole density averaged over the

  17. Fractal patterns applied to implant surface: definitions and perspectives.

    PubMed

    Dohan Ehrenfest, David M

    2011-10-01

    Fractal patterns are frequently found in nature, but they are difficult to reproduce in artificial objects such as implantable materials. In this article, a definition of the concept of fractals for osseointegrated surfaces is suggested, based on the search for quasi-self-similarity on at least 3 scales of investigation: microscale, nanoscale, and atomic/crystal scale. Following this definition, the fractal dimension of some surfaces may be defined (illustrated here with the Intra-Lock Ossean surface). However the biological effects of this architecture are still unknown and should be examined carefully in the future.

  18. Titanium oral implants: surface characteristics, interface biology and clinical outcome.

    PubMed

    Palmquist, Anders; Omar, Omar M; Esposito, Marco; Lausmaa, Jukka; Thomsen, Peter

    2010-10-06

    Bone-anchored titanium implants have revolutionized oral healthcare. Surface properties of oral titanium implants play decisive roles for molecular interactions, cellular response and bone regeneration. Nevertheless, the role of specific surface properties, such as chemical and phase composition and nanoscale features, for the biological in vivo performance remains to be established. Partly, this is due to limited transfer of state-of-the-art preparation techniques to complex three-dimensional geometries, analytical tools and access to minute, intact interfacial layers. As judged by the available results of a few randomized clinical trials, there is no evidence that any particular type of oral implant has superior long-term success. Important insights into the recruitment of mesenchymal stem cells, cell-cell communication at the interface and high-resolution imaging of the interface between the surface oxide and the biological host are prerequisites for the understanding of the mechanisms of osseointegration. Strategies for development of the next generation of material surface modifications for compromised tissue are likely to include time and functionally programmed properties, pharmacological modulation and incorporation of cellular components.

  19. Titanium oral implants: surface characteristics, interface biology and clinical outcome

    PubMed Central

    Palmquist, Anders; Omar, Omar M.; Esposito, Marco; Lausmaa, Jukka; Thomsen, Peter

    2010-01-01

    Bone-anchored titanium implants have revolutionized oral healthcare. Surface properties of oral titanium implants play decisive roles for molecular interactions, cellular response and bone regeneration. Nevertheless, the role of specific surface properties, such as chemical and phase composition and nanoscale features, for the biological in vivo performance remains to be established. Partly, this is due to limited transfer of state-of-the-art preparation techniques to complex three-dimensional geometries, analytical tools and access to minute, intact interfacial layers. As judged by the available results of a few randomized clinical trials, there is no evidence that any particular type of oral implant has superior long-term success. Important insights into the recruitment of mesenchymal stem cells, cell–cell communication at the interface and high-resolution imaging of the interface between the surface oxide and the biological host are prerequisites for the understanding of the mechanisms of osseointegration. Strategies for development of the next generation of material surface modifications for compromised tissue are likely to include time and functionally programmed properties, pharmacological modulation and incorporation of cellular components. PMID:20591849

  20. Biomechanical evaluation of dental implants with different surfaces: Removal torque and resonance frequency analysis in rabbits.

    PubMed

    Koh, Jung-Woo; Yang, Jae-Ho; Han, Jung-Suk; Lee, Jai-Bong; Kim, Sung-Hun

    2009-07-01

    Macroscopic and especially microscopic properties of implant surfaces play a major role in the osseous healing of dental implants. Dental implants with modified surfaces have shown stronger osseointegration than implants which are only turned (machined). Advanced surface modification techniques such as anodic oxidation and Ca-P application have been developed to achieve faster and stronger bonding between the host bone and the implant. The purpose of this study was to investigate the effect of surface treatment of titanium dental implant on implant stability after insertion using the rabbit tibia model. THREE TEST GROUPS WERE PREPARED: sandblasted, large-grit and acid-etched (SLA) implants, anodic oxidized implants, and anodized implants with Ca-P immersion. The turned implants served as control. Twenty rabbits received 80 implants in the tibia. Resonance frequencies were measured at the time of implant insertion, 2 weeks and 4 weeks of healing. Removal torque values (RTV) were measured 2 and 4 weeks after insertion. The implant stability quotient (ISQ) values of implants for resonance frequency analysis (RFA) increased significantly (P < .05) during 2 weeks of healing period although there were no significant differences among the test and control groups (P > .05). The test and control implants also showed significantly higher ISQ values during 4 weeks of healing period (P < .05). No significant differences, however, were found among all the groups. All the groups showed no significant differences in ISQ values between 2 and 4 weeks after implant insertion (P > .05). The SLA, anodized and Ca-P immersed implants showed higher RTVs at 2 and 4 weeks of healing than the machined one (P < .05). However, there was no significant difference among the experimental groups. The surface-modified implants appear to provide superior implant stability to the turned one. Under the limitation of this study, however, we suggest that neither anodic oxidation nor Ca-P immersion

  1. Plasma-based ion implantation and deposition: A review of physics,technology, and applications

    SciTech Connect

    Pelletier, Jacques; Anders, Andre

    2005-05-16

    After pioneering work in the 1980s, plasma-based ion implantation (PBII) and plasma-based ion implantation and deposition (PBIID) can now be considered mature technologies for surface modification and thin film deposition. This review starts by looking at the historical development and recalling the basic ideas of PBII. Advantages and disadvantages are compared to conventional ion beam implantation and physical vapor deposition for PBII and PBIID, respectively, followed by a summary of the physics of sheath dynamics, plasma and pulse specifications, plasma diagnostics, and process modeling. The review moves on to technology considerations for plasma sources and process reactors. PBII surface modification and PBIID coatings are applied in a wide range of situations. They include the by-now traditional tribological applications of reducing wear and corrosion through the formation of hard, tough, smooth, low-friction and chemically inert phases and coatings, e.g. for engine components. PBII has become viable for the formation of shallow junctions and other applications in microelectronics. More recently, the rapidly growing field of biomaterial synthesis makes used of PBII&D to produce surgical implants, bio- and blood-compatible surfaces and coatings, etc. With limitations, also non-conducting materials such as plastic sheets can be treated. The major interest in PBII processing originates from its flexibility in ion energy (from a few eV up to about 100 keV), and the capability to efficiently treat, or deposit on, large areas, and (within limits) to process non-flat, three-dimensional workpieces, including forming and modifying metastable phases and nanostructures. We use the acronym PBII&D when referring to both implantation and deposition, while PBIID implies that deposition is part of the process.

  2. Influence of implant shape, surface morphology, surgical technique and bone quality on the primary stability of dental implants.

    PubMed

    Elias, Carlos Nelson; Rocha, Felipe Assis; Nascimento, Ana Lucia; Coelho, Paulo Guilherme

    2012-12-01

    The primary stability of dental implants has been investigated before, but a study of the influence of implant shape, size and surface morphology (machined, acid etched or anodized), surgical technique (press-fit or undersized) and substrate (natural or simulated bone) on the primary stability of dental implants has not been reported. The present work intends to fill this gap. In this work, six different dental implants were inserted into and removed from synthetic and natural bone while measuring the torque. A total of 255 dental implants with three shapes, four sizes and three surface topographies were inserted into pig rib, PTFE and polyurethane. The implant sites were prepared using straight and tapered drills. The primary stability was estimated from the maximum insertion torque. Comparisons between samples were based on the maximum insertion torque (MIT), the maximum removal torque (MRT) and the torque ratio (TR=MRT/MIT). The insertion torque into pig ribs showed larger dispersion. All parameters (shape, size and surface morphology of the implant, surgical technique and substrate type) were found to have a significant influence on primary stability. The insertion of a tapered implant requires a higher torque than the insertion of a straight implant. Surface treatments improve the primary stability. The influence of the surgical technique is smaller than that of implant size and shape. The highest insertion torque was that of anodized tapered implants inserted into undersized sites. Finally, the primary stability of dental implants is highly dependent on implant design, surgical technique and substrate type. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. N + surface doping on nanoscale polymer fabrics via ion implantation

    NASA Astrophysics Data System (ADS)

    Ho Wong, Kenneth Kar; Zinke-Allmang, Martin; Wan, Wankei

    2006-08-01

    Non-woven poly(vinyl alcohol) (PVA) fabrics composed of small diameter (∼110 nm) fibers have been spun by an electrospinning technique and then have been modified by ion implantation. 1.7 MeV N+ ion implantation with a dose of 1.2 × 1016 ions/cm2 was applied on the fabrics through a metal foil at room temperature. By using scanning electron microscopy (SEM), no surface morphology degradation has been observed on the fabric after the ion beam treatment. The diameter of the fibers has shrunk by 30% to about 74 nm. X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS) show that nitrogen surface doping was achieved and the formation of two new functional chemical groups (N-Cdbnd O and C-N) in the PVA is observed.

  4. Future technology in cochlear implants: assessing the benefit.

    PubMed

    Briggs, Robert J S

    2011-05-01

    It has been over 50 years since Djourno and Eyries first attempted electric stimulation in a patient with deafness. Over this time, the Cochlear Implant (CI) has become not only remarkably successful, but increasingly complex. Although the basic components of the system still comprise an implanted receiver stimulator and electrode, externally worn speech processor, microphone, control system, and power source, there are now several alternative designs of these components with different attributes that can be variably combined to meet the needs of specific patient groups. Development by the manufacturers has been driven both by these various patient needs, and also by the desire to achieve technological superiority, or at least differentiation, ultimately in pursuit of market share. Assessment of benefit is the responsibility of clinicians. It is incumbent on both industry and clinicians to ensure appropriate, safe, and affordable introduction of new technology. For example, experience with the totally implanted cochlear implant (TIKI) has demonstrated that quality of hearing is the over-riding consideration for CI users. To date, improved hearing outcomes have been achieved by improvements in: speech processing strategies; microphone technology; pre-processing strategies; electrode placement; bilateral implantation; use of a hearing aid in the opposite ear (bimodal stimulation); and the combination of electric and acoustic stimulation in the same ear. The resulting expansion of CI candidacy, with more residual hearing, further improves the outcomes achieved. Largely facilitated by advances in electronic capability and computerization, it can be expected that these improvements will continue. However, marked variability of results still occurs and we cannot assure any individual patient of their outcome. Realistic goals for implementation of new technology include: improved hearing in noise and music perception; effective invisible hearing (no external apparatus

  5. Atomistic modeling of ion implantation technologies in silicon

    NASA Astrophysics Data System (ADS)

    Marqués, Luis A.; Santos, Iván; Pelaz, Lourdes; López, Pedro; Aboy, María

    2015-06-01

    Requirements for the manufacturing of electronic devices at the nanometric scale are becoming more and more demanding on each new technology node, driving the need for the fabrication of ultra-shallow junctions and finFET structures. Main implantation strategies, cluster and cold implants, are aimed to reduce the amount of end-of-range defects through substrate amorphization. During finFET doping the device body gets amorphized, and its regrowth is more problematic than in the case of conventional planar devices. Consequently, there is a renewed interest on the modeling of amorphization and recrystallization in the front-end processing of Si. We present multi-scale simulation schemes to model amorphization and recrystallization in Si from an atomistic perspective. Models are able to correctly predict damage formation, accumulation and regrowth, both in the ballistic and thermal-spike regimes, in very good agreement with conventional molecular dynamics techniques but at a much lower computational cost.

  6. Metal ion implantation for large scale surface modification

    SciTech Connect

    Brown, I.G.

    1992-10-01

    Intense energetic beams of metal ions can be produced by using a metal vapor vacuum arc as the plasma discharge from which the ion beam is formed. We have developed a number of ion sources of this kind and have built a metal ion implantation facility which can produce repetitively pulsed ion beams with mean ion energy up to several hundred key, pulsed beam current of more than an ampere, and time averaged current of several tens of milliamperes delivered onto a downstream target. We've also done some preliminary work on scaling up this technology to very large size. For example, a 50-cm diameter (2000 cm[sup 2]) set of beam formation electrodes was used to produce a pulsed titanium beam with ion current over 7 amperes at a mean ion energy of 100 key. Separately, a dc embodiment has been used to produce a dc titanium ion beam with current over 600 mA, power supply limited in this work, and up to 6 amperes of dc plasma ion current was maintained for over an hour. In a related program we've developed a plasma immersion method for applying thin metallic and compound films in which the added species is atomically mixed to the substrate. By adding a gas flow to the process, well-bonded compound films can also be formed; metallic films and multilayers as well as oxides and nitrides with mixed transition zones some hundreds of angstroms thick have been synthesized. Here we outline these parallel metal-plasma-based research programs and describe the hardware that we've developed and some of the surface modification research that we've done with it.

  7. Highly antibacterial UHMWPE surfaces by implantation of titanium ions

    NASA Astrophysics Data System (ADS)

    Delle Side, D.; Nassisi, V.; Giuffreda, E.; Velardi, L.; Alifano, P.; Talà, A.; Tredici, S. M.

    2014-07-01

    The spreading of pathogens represents a serious threat for human beings. Consequently, efficient antimicrobial surfaces are needed in order to reduce risks of contracting severe diseases. In this work we present the first evidences of a new technique to obtain a highly antibacterial Ultra High Molecular Weight Polyethylene (UHMWPE) based on a non-stoichiometric titanium oxide coating, visible-light responsive, obtained through ion implantation.

  8. Surface Functionalization of Orthopedic Titanium Implants with Bone Sialoprotein.

    PubMed

    Baranowski, Andreas; Klein, Anja; Ritz, Ulrike; Ackermann, Angelika; Anthonissen, Joris; Kaufmann, Kerstin B; Brendel, Christian; Götz, Hermann; Rommens, Pol M; Hofmann, Alexander

    2016-01-01

    Orthopedic implant failure due to aseptic loosening and mechanical instability remains a major problem in total joint replacement. Improving osseointegration at the bone-implant interface may reduce micromotion and loosening. Bone sialoprotein (BSP) has been shown to enhance bone formation when coated onto titanium femoral implants and in rat calvarial defect models. However, the most appropriate method of BSP coating, the necessary level of BSP coating, and the effect of BSP coating on cell behavior remain largely unknown. In this study, BSP was covalently coupled to titanium surfaces via an aminosilane linker (APTES), and its properties were compared to BSP applied to titanium via physisorption and untreated titanium. Cell functions were examined using primary human osteoblasts (hOBs) and L929 mouse fibroblasts. Gene expression of specific bone turnover markers at the RNA level was detected at different intervals. Cell adhesion to titanium surfaces treated with BSP via physisorption was not significantly different from that of untreated titanium at any time point, whereas BSP application via covalent coupling caused reduced cell adhesion during the first few hours in culture. Cell migration was increased on titanium disks that were treated with higher concentrations of BSP solution, independent of the coating method. During the early phases of hOB proliferation, a suppressive effect of BSP was observed independent of its concentration, particularly when BSP was applied to the titanium surface via physisorption. Although alkaline phosphatase activity was reduced in the BSP-coated titanium groups after 4 days in culture, increased calcium deposition was observed after 21 days. In particular, the gene expression level of RUNX2 was upregulated by BSP. The increase in calcium deposition and the stimulation of cell differentiation induced by BSP highlight its potential as a surface modifier that could enhance the osseointegration of orthopedic implants. Both

  9. Surface Functionalization of Orthopedic Titanium Implants with Bone Sialoprotein

    PubMed Central

    Ritz, Ulrike; Ackermann, Angelika; Anthonissen, Joris; Kaufmann, Kerstin B.; Brendel, Christian; Götz, Hermann; Rommens, Pol M.; Hofmann, Alexander

    2016-01-01

    Orthopedic implant failure due to aseptic loosening and mechanical instability remains a major problem in total joint replacement. Improving osseointegration at the bone-implant interface may reduce micromotion and loosening. Bone sialoprotein (BSP) has been shown to enhance bone formation when coated onto titanium femoral implants and in rat calvarial defect models. However, the most appropriate method of BSP coating, the necessary level of BSP coating, and the effect of BSP coating on cell behavior remain largely unknown. In this study, BSP was covalently coupled to titanium surfaces via an aminosilane linker (APTES), and its properties were compared to BSP applied to titanium via physisorption and untreated titanium. Cell functions were examined using primary human osteoblasts (hOBs) and L929 mouse fibroblasts. Gene expression of specific bone turnover markers at the RNA level was detected at different intervals. Cell adhesion to titanium surfaces treated with BSP via physisorption was not significantly different from that of untreated titanium at any time point, whereas BSP application via covalent coupling caused reduced cell adhesion during the first few hours in culture. Cell migration was increased on titanium disks that were treated with higher concentrations of BSP solution, independent of the coating method. During the early phases of hOB proliferation, a suppressive effect of BSP was observed independent of its concentration, particularly when BSP was applied to the titanium surface via physisorption. Although alkaline phosphatase activity was reduced in the BSP-coated titanium groups after 4 days in culture, increased calcium deposition was observed after 21 days. In particular, the gene expression level of RUNX2 was upregulated by BSP. The increase in calcium deposition and the stimulation of cell differentiation induced by BSP highlight its potential as a surface modifier that could enhance the osseointegration of orthopedic implants. Both

  10. Bioactivity and Surface Characteristics of Titanium Implants Following Various Surface Treatments: An In Vitro Study.

    PubMed

    Kumar K, Aswini; Bhatt, Vinaya; Balakrishnan, Manilal; Hashem, Mohamed; Vellappally, Sajith; Aziz A Al Kheraif, Abdul; Halawany, Hassan Suliman; Abraham, Nimmi Biju; Jacob, Vimal; Anil, Sukumaran

    2015-10-01

    This study compared the surface topography, hydrophilicity, and bioactivity of titanium implants after 3 different surface treatments (sandblasting and acid etching, modified sandblasting and acid etching, and thermal oxidation) with those of machined implants. One hundred indigenously manufactured threaded titanium implants were subjected to 3 methods of surface treatment. The surface roughness of the nontreated (Group A) and treated samples (Groups B through D) was evaluated with a scanning electron microscope (SEM) and profilometer. The wettability was visually examined using a colored dye solution. The calcium ions attached to the implant surface after immersing in simulated body fluid (SBF) were assessed on days 1, 2, and 7 with an atomic electron spectroscope. The data were analyzed statistically. The SBF test allowed the precipitation of a calcium phosphate layer on all surface-treated samples, as evidenced in the SEM analysis. A significantly higher amount of calcium ions and increased wettability were achieved in the thermally oxidized samples. The mean roughness was significantly lower in Group A (0.85 ± 0.07) compared to Group B (1.35 ± 0.17), Group C (1.40 ± 0.14), and Group D (1.36 ± 0.18). The observations from this in vitro study indicated that surface treatment of titanium improved the bioactivity. Moreover, results identified the implants that were sandblasted, acid etched, and then oxidized attracted more calcium ions.

  11. Bacterial Biofilm Morphology on a Failing Implant with an Oxidized Surface: A Scanning Electron Microscope Study.

    PubMed

    Simion, Massimo; Kim, David M; Pieroni, Stefano; Nevins, Myron; Cassinelli, Clara

    2016-01-01

    This case report provided a unique opportunity to investigate the extent of microbiota infiltration on the oxidized implant surface that has been compromised by peri-implantitis. Scanning electron microscopic analysis confirmed the etiologic role of the bacteria on the loss of supporting structure and the difficulty in complete removal of bacterial infiltration on the implant surface. This case report emphasizes the need to perform definitive surface decontamination on failing dental implants prior to a regeneration procedure.

  12. Impact of new X-ray technology on patient dose in pacemaker and implantable cardioverter defibrillator (ICD) implantations.

    PubMed

    van Dijk, Joris D; Ottervanger, Jan Paul; Delnoy, Peter Paul H M; Lagerweij, Martine C M; Knollema, Siert; Slump, Cornelis H; Jager, Pieter L

    2017-01-01

    New X-ray technology providing new image processing techniques may reduce radiation exposure. The aim of this study was to quantify this radiation exposure reduction for patients during pacemaker and implantable cardioverter defibrillator (ICD) implantation. In this retrospective study, 1185 consecutive patients who had undergone de novo pacemaker or ICD implantation during a 2-year period were included. All implantations in the first year were performed using the reference technology (Allura Xper), whereas in the second year, the new X-ray technology (AlluraClarity) was used. Radiation exposure, expressed as the dose area product (DAP), was compared between the two time periods to determine the radiation exposure reduction for pacemaker and ICD implantations without cardiac resynchronization therapy (CRT) and with CRT. Procedure duration and contrast volume were used as measures to compare complexity and image quality. The study population consisted of 591 patients who had undergone an implantation using the reference technology, and 594 patients with the new X-ray technology. The two groups did not differ in age, gender, or body mass index. The DAP decreased with 69 % from 16.4 ± 18.5 to 5.2 ± 6.6 Gy cm(2) for the non-CRT implantations (p < 0.001). The DAP decreased with 75 % from 72.1 ± 60.0 to 17.8 ± 17.4 Gy cm(2) for the CRT implantations (p < 0.001). Nevertheless, procedure duration and contrast volume did not differ when using the new technology (p = 0.09 and p = 0.20, respectively). Introduction of new X-ray technology resulted in a radiation exposure reduction of more than 69 % for patients during pacemaker and ICD implantation while image quality was unaffected.

  13. Laser bioengineering of glass-titanium implants surface

    NASA Astrophysics Data System (ADS)

    Lusquiños, F.; Arias-González, F.; Penide, J.; del Val, J.; Comesaña, R.; Quintero, F.; Riveiro, A.; Boutinguiza, M.; Pascual, M. J.; Durán, A.; Pou, J.

    2013-11-01

    Osseointegration is the mean challenge when surgical treatments fight against load-bearing bone diseases. Absolute bone replacement by a synthetic implant has to be completed not only from the mechanics point of view, but also from a biological approach. Suitable strength, resilience and stress distribution of titanium alloy implants are spoiled by the lack of optimal biological characteristics. The inert quality of extra low interstitial titanium alloy, which make it the most attractive metallic alloy for biomedical applications, oppose to an ideal surface with bone cell affinity, and capable to stimulate bone attachment bone growth. Diverse laser treatments have been proven as effective tools to modify surface properties, such as wettability in contact to physiological fluids, or osteoblast guided and slightly enhanced attachment. The laser surface cladding can go beyond by providing titanium alloy surfaces with osteoconduction and osteoinduction properties. In this research work, the laser radiation is used to produce bioactive glass coatings on Ti6Al4V alloy substrates. Specific silicate bioactive glass compositions has been investigated to achieve suitable surface tension and viscosity temperature behavior during processing, and to provide with the required release of bone growth gene up regulation agents in the course of resorption mediated by physiological fluids. The produced coatings and interfaces, the surface osteoconduction properties, and the chemical species release in simulated physiological fluid were characterized by scanning electron microscopy (SEM), hot stage microscopy (HSM), X-ray diffraction (XRD), X ray fluorescence (XRF), and Fourier transform infrared spectroscopy (FTIR).

  14. Method for Fabricating Soft Tissue Implants with Microscopic Surface Roughness

    NASA Technical Reports Server (NTRS)

    Banks, Bruce A. (Inventor); Rutledge, Sharon K. (Inventor)

    1999-01-01

    A method for fabricating soft tissue implants using a mold. The cavity surface of an initially untextured mold. made of an organic material such as epoxy. is given a thin film coating of material that has pinholes and is resistant to atomic particle bombardment. The mold cavity surface is then subjected to atomic particle bombardment, such as when placed in an isotropic atomic oxygen environment. Microscopic depressions in the mold cavity surface are created at the pinhole sites on the thin film coating. The thin film coating is removed and the mold is then used to cast the soft tissue implant. The thin film coating having pinholes may be created by chilling the mold below the dew point such that water vapor condenses upon it; distributing particles, that can partially dissolve and become attached to the mold cavity surface, onto the mold cavity surface; removing the layer of condensate, such as by evaporation; applying the thin film coating over the entire mold surface; and, finally removing the particles, such as by dissolving or brushing it off. Pinholes are created in the thin film coating at the sites previously occupied by the particles.

  15. Priming the Surface of Orthopedic Implants for Osteoblast Attachment in Bone Tissue Engineering

    PubMed Central

    Chan, Kiat Hwa; Zhuo, Shuangmu; Ni, Ming

    2015-01-01

    The development of better orthopedic implants is incessant. While current implants can function reliably in the human body for a long period of time, there are still a significant number of cases for which the implants can fail prematurely due to poor osseointegration of the implant with native bone. Increasingly, it is recognized that it is extremely important to facilitate the attachment of osteoblasts on the implant so that a proper foundation of extracellular matrix (ECM) can be laid down for the growth of new bone tissue. In order to facilitate the osseointegration of the implant, both the physical nanotopography and chemical functionalization of the implant surface have to be optimized. In this short review, however, we explore how simple chemistry procedures can be used to functionalize the surfaces of three major classes of orthopedic implants, i.e. ceramics, metals, and polymers, so that the attachment of osteoblasts on implants can be facilitated in order to promote implant osseointegration. PMID:26392807

  16. Enhanced implant stability with a chemically modified SLA surface: a randomized pilot study.

    PubMed

    Oates, Thomas W; Valderrama, Pilar; Bischof, Mark; Nedir, Rabah; Jones, Archie; Simpson, James; Toutenburg, Helge; Cochran, David L

    2007-01-01

    Chemical modification to a sandblasted, large-grit, acid-etched (SLA) implant surface has been shown to enhance the rate of osseointegration. The goal of the present study was to examine changes in stability for implants with a chemically modified SLA surface and to compare their outcomes to those of control implants. A randomized controlled trial was conducted with 31 patients. Each patient received 2 implants with the same physical properties but with surfaces that were chemically different. The control implants had a standard SLA surface, while the test implants had a chemically modified surface. Resonance frequency analysis was assessed weekly over the first 6 weeks following implant placement. All implants proved clinically successful, allowing for restoration. Most implants were placed in the mandible (50 of 62). A shift in implant stability from decreasing stability to increasing stability (P < .001), occurred after 2 weeks for the test implants and after 4 weeks for the control implants. The findings from this pilot study provide clinical support for the potential for chemical modification of the SLA surface to alter biologic events during the osseointegration process and demonstrate levels of short-term clinical success similar to those observed for implants with an SLA surface.

  17. Implantable optogenetic device with CMOS IC technology for simultaneous optical measurement and stimulation

    NASA Astrophysics Data System (ADS)

    Haruta, Makito; Kamiyama, Naoya; Nakajima, Shun; Motoyama, Mayumi; Kawahara, Mamiko; Ohta, Yasumi; Yamasaki, Atsushi; Takehara, Hiroaki; Noda, Toshihiko; Sasagawa, Kiyotaka; Ishikawa, Yasuyuki; Tokuda, Takashi; Hashimoto, Hitoshi; Ohta, Jun

    2017-05-01

    In this study, we have developed an implantable optogenetic device that can measure and stimulate neurons by an optical method based on CMOS IC technology. The device consist of a blue LED array for optically patterned stimulation, a CMOS image sensor for acquiring brain surface image, and eight green LEDs surrounding the CMOS image sensor for illumination. The blue LED array is placed on the CMOS image sensor. We implanted the device in the brain of a genetically modified mouse and successfully demonstrated the stimulation of neurons optically and simultaneously acquire intrinsic optical images of the brain surface using the image sensor. The integrated device can be used for simultaneously measuring and controlling neuronal activities in a living animal, which is important for the artificial control of brain functions.

  18. Biomechanical evaluation of laser-etched Ti implant surfaces vs. chemically modified SLA Ti implant surfaces: Removal torque and resonance frequency analysis in rabbit tibias.

    PubMed

    Lee, Jung-Tae; Cho, Sung-Am

    2016-08-01

    To compare osseointegration and implant stability of two types of laser-etched (LE) Ti implants with a chemically-modified, sandblasted, large-grit and acid-etched (SLA) Ti implant (SLActive(®), Straumann, Basel, Switzerland), by evaluating removal torque and resonance frequency between the implant surface and rabbit tibia bones. We used conventional LE Ti implants (conventional LE implant, CSM implant, Daegu, Korea) and LE Ti implants that had been chemically activated with 0.9% NaCl solution (LE active implant) for comparison with SLActive(®) implants Two types of 3.3×8mm laser-etched Ti implants - conventional LE implants and LE active implants were prepared. LE implants and SLActive(®) implants were installed on the left and right tibias of 10 adult rabbits weighing approximately 3.0kg LE active implants and SLActive(®) implants were installed on the left and right tibias of 11 adult rabbits. After installation, we measured insertion torque (ITQ) and resonance frequency (ISQ). Three weeks (LE active) or 4 weeks (conventional LE) after installation, we measured removal torque (RTQ) and ISQ. In the conventional LE experiment, the mean ITQ was 16.99±6.35Ncm for conventional LE implants and 16.11±7.36Ncm for SLActive(®) implants (p=0.778>0.05). After 4 weeks, the mean of RTQ was 39.49±17.3Ncm for LE and 42.27±20.5Ncm for SLActive(®) (p=0.747>0.05). Right after insertion of the implants, the mean ISQ was 74.8±4.98 for conventional LE and 70.1±9.15 for SLActive(®) implants (p=0.169>0.05). After 4 weeks, the mean ISQ was 64.40±6.95 for LE and 67.70±9.83 for SLActive(®) (p=0.397>0.05). In the LE active experiment, the mean ITQ was 16.24±7.49Ncm for LE active implants and 14.33±5.06Ncm for SLActive(®) implants (p=0.491>0.05). After 3 weeks, the mean RTQ was 39.25±16.41Ncm for LE active and 41.56±10.41Ncm for SLActive(®) implants (p=0.698>0.05). Right after insertion of the implants, the mean ISQ was 58.64±10.51 for LE active implants and 53.82

  19. Decontamination of Anodized Implant Surface With Different Modalities for Peri-Implantitis Treatment: Lasers and Mechanical Debridement With Citric Acid.

    PubMed

    Htet, Moe; Madi, Marwa; Zakaria, Osama; Miyahara, Takayuki; Xin, Wang; Lin, Zayar; Aoki, Kazuhiro; Kasugai, Shohei

    2016-08-01

    Although oral rehabilitation with dental implants is a very promising and effective procedure, peri-implantitis is an emerging concern. Surgical and non-surgical methods have been applied to treat peri-implantitis together with various implant surface decontamination methods. However, there is no consensus concerning the most effective treatment for peri-implantitis. The aim of the present study is to evaluate the effects of erbium-doped:yttrium, aluminum, and garnet (Er:YAG) laser, photodynamic therapy (PDT), and titanium bur with and without citric acid on ligature-induced peri-implantitis around an anodized implant surface. Thirty dental implants with anodized surface (3.3 × 10 mm) were installed in the mandibles of five beagle dogs. After 3 months, peri-implantitis was induced by applying cotton ligatures subgingivally. After ligature removal (baseline), the implants were divided into the following treatment groups: 1) Er:YAG laser, 2) PDT, 3) titanium bur alone, and 4) titanium bur with citric acid. Animals were sacrificed after 3 months, and clinical, radiologic, histologic, and histomorphometric evaluations were conducted for all treatment modalities. The data were analyzed using one-way analysis of variance and Tukey test. A value of P <0.05 was considered statistically significant. The titanium bur with citric acid group exhibited statistically significantly greater improvement in vertical bone height than the Er:YAG laser group and significantly better bone-to-implant contact than the PDT group and the bur-alone group. Within the limits of the study, the combination of mechanical and chemical treatment proved to be the most effective treatment for disinfection of the anodized implant surface.

  20. Histologic analysis of resorbable blasting media surface implants retrieved from humans: a report of two cases

    PubMed Central

    2016-01-01

    The purpose of this study is to evaluate the degree of osseointegration of resorbable blasting media (RBM) surface implants retrieved from humans. Three implants in the mandibular molar region that were surface-treated with RBM were retrieved from two patients. The implants were used to manufacture specimens in order to measure the bone-implant contact (BIC) ratio. The BIC ratios of the three implants were found to be an average of 69.0%±9.1%. In conclusion, that RBM surface implants are integrated into the host environment with histological significance and the BIC ratio of the RBM surface-treated implant was not significantly different from that of other surface-treated implants. PMID:26904493

  1. Surface modification of titanium and titanium alloys by ion implantation.

    PubMed

    Rautray, Tapash R; Narayanan, R; Kwon, Tae-Yub; Kim, Kyo-Han

    2010-05-01

    Titanium and titanium alloys are widely used in biomedical devices and components, especially as hard tissue replacements as well as in cardiac and cardiovascular applications, because of their desirable properties, such as relatively low modulus, good fatigue strength, formability, machinability, corrosion resistance, and biocompatibility. However, titanium and its alloys cannot meet all of the clinical requirements. Therefore, to improve the biological, chemical, and mechanical properties, surface modification is often performed. In view of this, the current review casts new light on surface modification of titanium and titanium alloys by ion beam implantation.

  2. Polyspecies biofilm formation on implant surfaces with different surface characteristics

    PubMed Central

    SCHMIDLIN, Patrick R.; MÜLLER, Phillip; ATTIN, Thomas; WIELAND, Marco; HOFER, Deborah; GUGGENHEIM, Bernhard

    2013-01-01

    Objective: To investigate the microbial adherence and colonization of a polyspecies biofilm on 7 differently processed titanium surfaces. Material and Methods: Six-species biofilms were formed anaerobically on 5-mm-diameter sterilized, saliva-preconditioned titanium discs. Material surfaces used were either machined, stained, acid-etched or sandblasted/acid-etched (SLA). Samples of the latter two materials were also provided in a chemically modified form, with increased wettability characteristics. Surface roughness and contact angles of all materials were determined. The discs were then incubated anaerobically for up to 16.5 h. Initial microbial adherence was evaluated after 20 min incubation and further colonization after 2, 4, 8, and 16.5 h using non-selective and selective culture techniques. Results at different time points were compared using ANOVA and Scheffé post hoc analysis. Results: The mean differences in microorganisms colonizing after the first 20 min were in a very narrow range (4.5 to 4.8 log CFU). At up to 16.5 h, the modified SLA surface exhibited the highest values for colonization (6.9±0.2 log CFU, p<0.05) but increasing growth was observed on all test surfaces over time. Discrepancies among bacterial strains on the differently crafted titanium surfaces were very similar to those described for total log CFU. F. nucleatum was below the detection limit on all surfaces after 4 h. Conclusion: Within the limitations of this in vitro study, surface roughness had a moderate influence on biofilm formation, while wettability did not seem to influence biofilm formation under the experimental conditions described. The modified SLA surface showed the highest trend for bacterial colonization. PMID:23559112

  3. Effect of surface chemistry on the rate of osseointegration of sintered porous-surfaced Ti-6Al-4V implants.

    PubMed

    Taché, Alex; Gan, Lu; Deporter, Douglas; Pilliar, Robert M

    2004-01-01

    The effect of adding a thin sol-gel-formed calcium phosphate (CaP) coating to sintered porous-surfaced titanium alloy (Ti-6Al-4V) implants on rates of initial bone ingrowth was investigated. Control implants (as manufactured) and similar implants with sol-gel CaP coatings were randomly placed in distal femoral rabbit condyles (1 implant/leg). After healing for 6, 9, 12, and 16 days, 8 of 10 rabbits in each time group were assessed for maximum implant pullout force (N) and interface stiffness (N/mm). Selected extracted implants also were examined by secondary electron imaging to characterize affected surfaces. The implants of the remaining 2 rabbits in each group were examined by backscattered scanning electron microscopy (BSEM). Significantly greater pullout forces and interface stiffness were found for CaP-coated implants at 6 and 9 days. At 6 days, BSEM revealed bone ingrowth on CaP-coated implants but not on control implants. Secondary electron imaging and BSEM observations also suggested greater bone ingrowth with CaP-coated porous implants at 9, 12, and 16 days. Sol-gel-formed CaP surface films significantly enhance rates of bone ingrowth into sintered porous-surfaced implants. This surface treatment may have a number of clinical benefits, including shortening the period prior to functional loading of such implants and improving treatment outcomes in situations of poor bone quality and/or quantity. (More than 50 references).

  4. A bone-like precoating strategy for implants: collagen immobilization and mineralization on pure titanium implant surface.

    PubMed

    Munisamy, S; Vaidyanathan, T K; Vaidyanathan, J

    2008-01-01

    Many surface modification strategies are currently of interest in improving integration of implants to bone. An in vitro precoating of a bone-like mineralized layer of immobilized collagen on the implant surface is a potentially valuable approach to improve host acceptance of the implant. The goal of this investigation was to develop a method to precoat in vitro a bone-like mineralized collagen layer on a pure titanium dental implant surface. The study was conducted on acid-etched and nonetched surfaces of screw implants. Initially, a procedure was standardized to self-assemble collagen from a collagen solution. In subsequent experiments, the implant was also placed inside the solution, and after 3 days, collagen was found to be coated on the implant surface. Mineralization of the collagen gel as well as collagen coating on the implant was carried out by calcium phosphate precipitation from a mineralizing solution of calcium chloride containing polyvinyl phosphonic acid and polyaspartic acid, which served as polyanionic additives to help disperse the precipitation and template mineral nucleation. The implant was kept in the mineralizing solution and maintained for 2 weeks in an incubator at 37 degrees C with a phosphate vapor phase generated from a vial containing dihydrogen ammonium phosphate in the incubator. Scanning electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy analysis confirmed the coated layer to be a biomimetic bone-like mineralized type 1 collagen. Initial studies using osteoblast-like cells indicated cellular attachment on the modified surface. The method appears to be a promising way to generate in vitro a bone-like layer on the implant surface.

  5. A hydrophilic dental implant surface exhibits thrombogenic properties in vitro.

    PubMed

    Hong, Jaan; Kurt, Seta; Thor, Andreas

    2013-02-01

    Surface modifications of dental implants have gained attention during several years and the thrombotic response from blood components with these materials has become more important during recent years. The aims of this study were to evaluate the thrombogenic response of whole blood, in contact with clinically used dental surfaces, Sandblasted Large grit Acid etched titanium (SLA) and Sandblasted Large grit Acid etched, and chemically modified titanium with hydrophilic properties (SLActive). An in vitro slide chamber model, furnished with heparin, was used in which whole blood came in contact with slides of the test surfaces. After incubation (60-minute rotation at 22 rpm in a 37°C water bath), blood was mixed with ethylenediaminetetraacetic acid (EDTA) or citrate, further centrifuged at +4°C. Finally, plasma was collected pending analysis. Whole blood in contact with surfaces resulted in significantly higher binding of platelets to the hydrophilic surface, accompanied by a significant increase of contact activation of the coagulation cascade. In addition, the platelet activation showed a similar pattern with a significant elevated release of β-TG from platelet granule. The conclusion that can be drawn from the results in our study is that the hydrophilic modification seems to augment the thrombogenic properties of titanium with implications for healing into bone of, that is titanium dental implants. © 2011 Wiley Periodicals, Inc.

  6. Toward optimizing dental implant performance: Surface characterization of Ti and TiZr implant materials.

    PubMed

    Murphy, M; Walczak, M S; Thomas, A G; Silikas, N; Berner, S; Lindsay, R

    2017-01-01

    Targeting understanding enhanced osseointegration kinetics, the goal of this study was to characterize the surface morphology and composition of Ti and TiZr dental implant substrates subjected to one of two surface treatments developed by Straumann. These two treatments are typically known as SLA and SLActive, with the latter resulting in more rapid osseointegration. A range of techniques was applied to characterize four different substrate/surface treatment combinations (TiSLA, TiSLActive, TiZrSLA, and TiZrSLActive). Contact angle measurements established their hydrophilic/hydrophobic nature. Surface morphology was probed with scanning electron microscopy. X-ray diffraction, Raman μ-spectroscopy, and X-ray photoelectron spectroscopy were used to elucidate the composition of the near-surface region. Consistent with previous work, surface morphology was found to differ only at the nanoscale, with both SLActive substrates displaying nano-protrusions. Spectroscopic data indicate that all substrates exhibit surface films of titanium oxide displaying near TiO2 stoichiometry. Raman μ-spectroscopy reveals that amorphous TiO2 is most likely the only phase present on TiSLA, whilst rutile-TiO2 is also evidenced on TiSLActive, TiZrSLA, and TiZrSLActive. For TiZr alloy substrates, there is no evidence of discrete phases of oxidized Zr. X-ray photoelectron spectra demonstrate that all samples are terminated by adventitious carbon, with it being somewhat thicker (∼1nm) on TiSLA and TiZrSLA. Given previous in vivo studies, acquired data suggest that both nanoscale protrusions, and a thinner layer of adventitious carbon contribute to the more rapid osseointegration of SLActive dental implants. Composition of the surface oxide layer is apparently less important in determining osseointegration kinetics. Copyright © 2016 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  7. Effect of surface roughness and calcium phosphate coating on the implant/bone response.

    PubMed

    Hayakawa, T; Yoshinari, M; Nemoto, K; Wolke, J G; Jansen, J A

    2000-08-01

    The influence of surface roughness and calcium phosphate (Ca-P) coating on the bone response of titanium implants was investigated. Four types of titanium implants, i.e. as-machined, grit blasted, as-machined with Ca-P sputter coating, and grit blasted with Ca-P sputter coating, were prepared. The Ca-P sputter-coating, produced by using the RF magnetron sputter technique, was rapid heat-treated with infrared radiation at 600 degrees C. These implants were inserted into the left and right femoral condyles and the left and right tibial diaphyses of the rabbits. After implantation periods of 2 and 12 weeks, the bone-implant interface was evaluated histologically and histomorphometrically. Histological evaluation revealed no new bone formation around different implant materials after 2 weeks of implantation. After 12 weeks, bone healing was almost completed. For both tibial and femoral implants, Ca-P coated implants always showed a higher amount of bone contact than either of the non-coated implants. On the other hand, surface roughness improved only the response to implants inserted into the tibial diaphysis. On the basis of these findings, we concluded that 1) deposition of a sputtered Ca-P coating on an implant has a beneficial effect on the bone response to this implant during the healing phase, and 2) besides implant surface conditions the bone response is also determined by local implant site conditions.

  8. Decontamination of titanium implant surface and re-osseointegration to treat peri-implantitis: a literature review.

    PubMed

    Subramani, Karthikeyan; Wismeijer, Daniel

    2012-01-01

    To review the literature on decontamination of titanium implant surfaces following peri-implantitis and the effect of various cleaning methods on re-osseointegration. An electronic search of the literature at PubMed was conducted on the studies published between 1966 and October 2010. In vitro, animal, and clinical studies were included. Of 597 studies retrieved, 74 manuscripts were selected for the review. Various implant surface decontamination methods using various chemical and mechanical agents have been suggested for treatment and re-osseointegration following periimplantitis. It has been shown that re-osseointegration of contaminated implant surfaces is possible; this largely depends upon the surface of the implant and the types of decontamination techniques and bone regenerative materials used. Complete re-osseointegration cannot be achieved by surface decontamination alone. Titanium implants with titanium plasma-sprayed or sandblasted and acid-etched surfaces may be effectively decontaminated by applying chlorhexidine and saline-soaked gauze or by repeated rinsing with these solutions. Both mechanical and chemical decontamination techniques should be applied alongside regenerative surgical procedures to obtain optimum re-osseointegration and successfully treat peri-implantitis. In recent years, lasers and photodynamic therapy have shown minor beneficial results, which need to be confirmed by long-term clinical studies with comparable groups.

  9. Surface and subsurface decontamination technology

    SciTech Connect

    Tuck, Matt; Wray, Beth; Musgrave, Mark

    2013-07-01

    A number of proven technologies applicable to the chemical and physical decontamination of radioactive and non-radioactive contaminants within the environmental remediation and radiological waste management sectors exist. Previous work generally acknowledges that these methods have limitations such as production of large volumes of waste, destruction of the substrate, complex safety considerations [1a] and application of special precautions to meet disposal acceptance criteria [2]. A method that removes a variety of contaminants from the surface and subsurface of porous materials, with minimal contaminated waste arisings, is highly desirable. TechXtract{sup R} is a patented, sequential chemical extraction process developed to remove radionuclides, PCBs, and other hazardous organic and inorganic substances from solid materials such as concrete, brick, steel, and exotic metals [3]. The technology uses multifarious task-specific chemical formulations and engineered applications to achieve surface penetration and removal of the contaminants from the atomic voids of metals and other substrates, or the capillaries and gel pores of concretes. TechXtract{sup R} is proven to remove a variety of contaminants from various substrates, allowing free release of the substrate as waste for disposal, or re-use, whilst producing minimal secondary waste. Data from testing of TechXtract's capabilities and evidencing the technology's efficacy during site based applied research and development is presented here. (authors)

  10. Enhanced osteoconductivity of titanium implant by polarization-induced surface charges.

    PubMed

    Nozaki, Kosuke; Wang, Wei; Horiuchi, Naohiro; Nakamura, Miho; Takakuda, Kazuo; Yamashita, Kimihiro; Nagai, Akiko

    2014-09-01

    This study introduces the application of method for electrically polarizing titanium implants coated with anatase TiO2 using microarc oxidation. It also describes the features of the electrically polarized titanium implants, on which surface charges are generated by the dipole moment of the TiO2 , and describes how the surface charges affect the implants' in vivo bone-implant integration capability. A comprehensive assessment using biomechanical, histomorphological, and radiographic analyses in a rabbit model was performed on polarized and nonpolarized implants. The electrically polarized surfaces accelerated the establishment of implant biomechanical fixation, compared with the nonpolarized surfaces. The percentage of the bone-implant contact ratio was higher using polarized implants than using nonpolarized implants. In contrast, the bone volume around the implants was not affected by polarization. Thus, using the polarized implant, this study identified that controlled surface charges have a significant effect on the properties of titanium implants. The application of the electrical polarization process and the polarization-enhanced osteoinductivity, which resulted in greater bone-implant integration, was clearly demonstrated.

  11. Transcatheter pulmonary valve implantation: valve technology and procedural outcome.

    PubMed

    Salavitabar, Arash; Flynn, Patrick; Holzer, Ralf J

    2017-07-18

    Procedural technique and short-term outcomes of transcatheter pulmonary valve implantation (TPVI) have been widely described. The purpose of this article is to provide an update on current valve technology, and to focus on recent data surrounding TPVI in the dilated right ventricular outflow tract (RVOT), hybrid interventions, significant outcomes, and procedural costs. Transcatheter valve technology has expanded with current trials evaluating self-expandable valves that can be implanted in dilated RVOTs. Until those valves are widely available, hybrid techniques have been shown to offer a potential alternative in these patients, as well as in patients of small size. Although medium-term results of TPVI have shown 5-year freedom from reintervention or replacement of 76%, new data have underlined some concerns relating to bacterial endocarditis after the procedure. Procedural costs remain a concern, but vary greatly between institutions and healthcare systems. TPVI has emerged as one of the most innovative procedures in the treatment of patients with dysfunctional RVOT and pulmonary valves. Further device development is likely to expand the procedure to patients of smaller size and with complex, dilated RVOTs.

  12. In vitro and in vivo studies of surface-structured implants for bone formation

    PubMed Central

    Xia, Lu; Feng, Bo; Wang, Peizhi; Ding, Siyang; Liu, Zhiyuan; Zhou, Jie; Yu, Rong

    2012-01-01

    Background and methods Micronanoscale topologies play an important role in implant osteointegration and determine the success of an implant. We investigated the effect of three different implant surface topologies on osteoblast response and bone regeneration. In this study, implants with nanotubes and micropores were used, and implants with flat surfaces were used as the control group. Results Our in vitro studies showed that the nanostructured topologies improved the proliferation, differentiation, and development of the osteoblastic phenotype. Histological analysis further revealed that the nanotopology increased cell aggregation at the implant-tissue interfaces and enhanced bone-forming ability. Pushout testing indicated that the nanostructured topology greatly increased the bone-implant interfacial strength within 4 weeks of implantation. Conclusion Nanotopography may improve regeneration of bone tissue and shows promise for dental implant applications. PMID:23028216

  13. Ultrastructural investigation of intact orbital implant surfaces using atomic force microscopy.

    PubMed

    Choi, Samjin; Lee, Seung Jun; Shin, Jae-Ho; Cheong, Youjin; Lee, Hui-Jae; Paek, Joo Hee; Kim, Jae Sik; Jin, Kyung-Hyun; Park, Hun-Kuk

    2011-01-01

    This study examined the surface nanostructures of three orbital implants: nonporous poly(methyl methacrylate) (PMMA), porous aluminum oxide and porous polyethylene. The morphological characteristics of the orbital implants surfaces were observed by atomic force microscopy (AFM). The AFM topography, phase shift and deflection images of the intact implant samples were obtained. The surface of the nonporous PMMA implant showed severe scratches and debris. The surface of the aluminum oxide implant showed a porous structure with varying densities and sizes. The PMMA implant showed nodule nanostructures, 215.56 ± 52.34 nm in size, and the aluminum oxide implant showed crystal structures, 730.22 ± 341.02 nm in size. The nonporous PMMA implant showed the lowest roughness compared with other implant biomaterials, followed by the porous aluminum oxide implant. The porous polyethylene implant showed the highest roughness and severe surface irregularities. Overall, the surface roughness of orbital implants might be associated with the rate of complications and cell adhesion. Copyright © 2011 Wiley Periodicals, Inc.

  14. Treatment of peri-implantitis around TiUnite-surface implants using Er:YAG laser microexplosions.

    PubMed

    Yamamoto, Atsuhikp; Tanabe, Toshiichiro

    2013-01-01

    Implant therapy can lead to peri-implantitis, and none of the methods used to treat this inflammatory response have been predictably effective. It is nearly impossible to treat infected surfaces such as TiUnite (a titanium oxide layer) that promote osteoinduction, but finding an effective way to do so is essential. Experiments were conducted to determine the optimum irradiation power for stripping away the contaminated titanium oxide layer with Er:YAG laser irradiation, the degree of implant heating as a result of Er:YAG laser irradiation, and whether osseointegration was possible after Er:YAG laser microexplosions were used to strip a layer from the surface of implants placed in beagle dogs. The Er:YAG laser was effective at removing an even layer of titanium oxide, and the use of water spray limited heating of the irradiated implant, thus protecting the surrounding bone tissue from heat damage.

  15. Growth Inhibition of Tumour Implants by Associated Surface Active Agents

    PubMed Central

    Altman, R. F. A.; Spoladore, L. G.; Esch, E. L.

    1970-01-01

    Whereas dilute solutions of surface active agents modify the properties of cell membranes, particularly in relation to their electrical behaviour, moderate and strong solutions provoke more serious structural damage of the membrane, leading to an increase of its permeability and, finally, to cytolysis. These phenomena have inspired some authors to apply detergents as possible cancer chemotherapeuticals so far, however, with only poor results. The disintegrating effect of tumour emboli into single cells by certain detergents, and the ingenious discovery that the mutual adhesiveness between cancer cells is much less than between normal cells, have led the present authors to investigate the action of some biological surface active agents, alone as well as in some of their associations on the “take” of Yoshida sarcoma implants. Certain associations showed, in contradistinction to the separately applied components, surprisingly favourable activity. It could be established that a correlation actually exists between inhibitory effect and surface activity. PMID:4394469

  16. Effect of Zirconia Dental Implant Surfaces on Bone Integration: A Systematic Review and Meta-Analysis

    PubMed Central

    2017-01-01

    Background. The information available about osseointegration and the bone to implant interaction of zirconia implants with various surface modifications is still far from sufficient. Objective. The purpose of this systematic review and meta-analysis was to evaluate and compare zirconia dental implants with different surface topographies, with a focus on bone to implant contact and removal torque. Methods. The systematic review of the extracted publications was performed to compare the bone to implant contact (BIC) with removal torque (RT) values of titanium dental implants and machined and surfaced modified zirconia implants. Results. A total of fifteen articles on BIC and RT values were included in the quantitative analysis. No significant difference in the BIC values was observed between titanium and machined zirconia implants (p = 0.373; 95% CI: −0.166 to 0.443). However, a significantly better BIC values were observed for acid etched zirconia implants compared with those of titanium implants (p = 0.032; 95% CI: 0.068 to 1.461). Unmodified zirconia implants showed favorable BIC values compared to modified-surface zirconia implants (p = 0.021; 95% CI: −0.973 to −0.080). Conclusion. Acid etched zirconia implants may serve as a possible substitute for successful osseointegration. PMID:28299337

  17. Effect of Zirconia Dental Implant Surfaces on Bone Integration: A Systematic Review and Meta-Analysis.

    PubMed

    Hafezeqoran, Ali; Koodaryan, Roodabeh

    2017-01-01

    Background. The information available about osseointegration and the bone to implant interaction of zirconia implants with various surface modifications is still far from sufficient. Objective. The purpose of this systematic review and meta-analysis was to evaluate and compare zirconia dental implants with different surface topographies, with a focus on bone to implant contact and removal torque. Methods. The systematic review of the extracted publications was performed to compare the bone to implant contact (BIC) with removal torque (RT) values of titanium dental implants and machined and surfaced modified zirconia implants. Results. A total of fifteen articles on BIC and RT values were included in the quantitative analysis. No significant difference in the BIC values was observed between titanium and machined zirconia implants (p = 0.373; 95% CI: -0.166 to 0.443). However, a significantly better BIC values were observed for acid etched zirconia implants compared with those of titanium implants (p = 0.032; 95% CI: 0.068 to 1.461). Unmodified zirconia implants showed favorable BIC values compared to modified-surface zirconia implants (p = 0.021; 95% CI: -0.973 to -0.080). Conclusion. Acid etched zirconia implants may serve as a possible substitute for successful osseointegration.

  18. Adaptation of NASA technology for the optimum design of orthopedic knee implants.

    PubMed

    Saravanos, D A; Mraz, P J; Davy, D T; Hopkins, D A

    1991-03-01

    NASA technology originally developed for designing aircraft turbine-engine blades has been adapted and applied to orthopedic knee implants. This article describes a method for tailoring an implant for optimal interaction with the environment of the tibia. The implant components are designed to control stresses in the bone for minimizing bone degradation and preventing failures. Engineers expect the tailoring system to improve knee prosthesis design and allow customized implants for individual patients.

  19. Non-Destructive Analysis of Basic Surface Characteristics of Titanium Dental Implants Made by Miniature Machining

    NASA Astrophysics Data System (ADS)

    Babík, Ondrej; Czán, Andrej; Holubják, Jozef; Kameník, Roman; Pilc, Jozef

    2016-12-01

    One of the most best-known characteristic and important requirement of dental implant is made of biomaterials ability to create correct interaction between implant and human body. The most implemented material in manufacturing of dental implants is titanium of different grades of pureness. Since most of the implant surface is in direct contact with bone tissue, shape and integrity of said surface has great influence on the successful osseointegration. Among other characteristics of titanium that predetermine ideal biomaterial, it shows a high mechanical strength making precise machining miniature Increasingly difficult. The article is focused on evaluation of the resulting quality, integrity and characteristics of dental implants surface after machining.

  20. Detection and removal of pathogenic biofilms on medical implant surfaces.

    PubMed

    Dunlop, Patrick; Oliver, Louise; Byrne, Tony; McAdams, Eric

    2005-01-01

    Advances in sensor technology have had a significant impact in medical research and practice in the last decade. However, within the hospital environment problems still exist where the application of sensing technology could provide the solution. The presence of antibiotic resistant bacteria within hospitals and the risk of serious infection that they pose is a cause for concern. This paper describes a research project that has recently started at the University of Ulster investigating the potential of "Sense and Destroy" tactics to reduce the spread of medical device related infections. It is proposed that Electrical Impedance Spectroscopy (EIS) probes implanted within a catheter may be used to detect subclinical biofilm formation. Furthermore, if the presence of a biofilm is detected, activation of a photocatalytic coating on the catheter wall may be used to inactivate the responsible microorganisms.

  1. In Vitro Laser Treatment Platform Construction with Dental Implant Thread Surface on Bacterial Adhesion for Peri-Implantitis.

    PubMed

    Kuo, Hsien-Nan; Mei, Hsiang-I; Liu, Tung-Kuan; Liu, Tse-Ying; Lo, Lun-Jou; Lin, Chun-Li

    2017-01-01

    This study constructs a standard in vitro laser treatment platform with dental implant thread surface on bacterial adhesion for peri-implantitis at different tooth positions. The standard clinical adult tooth jaw model was scanned to construct the digital model with 6 mm bone loss depth on behalf of serious peri-implantitis at the incisor, first premolar, and first molar. A cylindrical suite connected to the implant and each tooth root in the jaw model was designed as one experimental unit set to allow the suite to be replaced for individual bacterial adhesion. The digital peri-implantitis and suite models were exported to fulfill the physical model using ABS material in a 3D printer. A 3 mm diameter specimen implant on bacterial adhesion against Escherichia coli was performed for gram-negative bacteria. An Er:YAG laser, working with a chisel type glass tip, was moved from the buccal across the implant thread to the lingual for about 30 seconds per sample to verify the in vitro laser treatment platform. The result showed that the sterilization rate can reach 99.3% and the jaw model was not damaged after laser irradiation testing. This study concluded that using integrated image processing, reverse engineering, CAD system, and a 3D printer to construct a peri-implantitis model replacing the implant on bacterial adhesion and acceptable sterilization rate proved the feasibility of the proposed laser treatment platform.

  2. In Vitro Laser Treatment Platform Construction with Dental Implant Thread Surface on Bacterial Adhesion for Peri-Implantitis

    PubMed Central

    Mei, Hsiang-I; Liu, Tse-Ying; Lo, Lun-Jou

    2017-01-01

    This study constructs a standard in vitro laser treatment platform with dental implant thread surface on bacterial adhesion for peri-implantitis at different tooth positions. The standard clinical adult tooth jaw model was scanned to construct the digital model with 6 mm bone loss depth on behalf of serious peri-implantitis at the incisor, first premolar, and first molar. A cylindrical suite connected to the implant and each tooth root in the jaw model was designed as one experimental unit set to allow the suite to be replaced for individual bacterial adhesion. The digital peri-implantitis and suite models were exported to fulfill the physical model using ABS material in a 3D printer. A 3 mm diameter specimen implant on bacterial adhesion against Escherichia coli was performed for gram-negative bacteria. An Er:YAG laser, working with a chisel type glass tip, was moved from the buccal across the implant thread to the lingual for about 30 seconds per sample to verify the in vitro laser treatment platform. The result showed that the sterilization rate can reach 99.3% and the jaw model was not damaged after laser irradiation testing. This study concluded that using integrated image processing, reverse engineering, CAD system, and a 3D printer to construct a peri-implantitis model replacing the implant on bacterial adhesion and acceptable sterilization rate proved the feasibility of the proposed laser treatment platform. PMID:28791302

  3. The power of disruptive technological innovation: Transcatheter aortic valve implantation.

    PubMed

    Berlin, David B; Davidson, Michael J; Schoen, Frederick J

    2015-11-01

    We sought to evaluate the principles of disruptive innovation, defined as technology innovation that fundamentally shifts performance and utility metrics, as applied to transcatheter aortic valve implantation (TAVI). In particular, we considered implantation procedure, device design, cost, and patient population. Generally cheaper and lower performing, classical disruptive innovations are first commercialized in insignificant markets, promise lower margins, and often parasitize existing usage, representing unattractive investments for established market participants. However, despite presently high unit cost, TAVI is less invasive, treats a "new," generally high risk, patient population, and is generally done by a multidisciplinary integrated heart team. Moreover, at least in the short-term TAVI has not been lower-performing than open surgical aortic valve replacement in high-risk patients. We conclude that TAVI extends the paradigm of disruptive innovation and represents an attractive commercial opportunity space. Moreover, should the long-term performance and durability of TAVI approach that of conventional prostheses, TAVI will be an increasingly attractive commercial opportunity.

  4. A Method of Producing Surface Conduction on Ceramic Accelerator Components Using Metal Ion Implantation

    SciTech Connect

    Liu, F.; Brown, I.; Phillips, H.; Biallas, George; Siggins, Timothy

    1997-05-01

    An important technique used for the suppression of surface flashover on high voltage DC ceramic insulators as well as for RF windows is that of providing some surface conduction to bleed off accumulated surface charge. We have used metal ion implantation to modify the surface of high voltage ceramic vacuum insulators to provide a niform surface resistivity of approximately 5 x 1010 W/square. A vacuum arc ion source based implanter was used to implant Pt at an energy of about 135 keV to doses of up to more than 5 x 1016 ions/cm2 into small ceramic test coupons and also into the inside surface of several ceramic accelerator columns 25 cm I. D. by 28 cm long. Here we describe the experimental set-up used to do the ion implantation and summarize the results of our exploratory work on implantation into test coupons as well as the implantations of the actual ceramic columns.

  5. Biomechanical and histomorphometric study of dental implants with different surface characteristics.

    PubMed

    Yeo, In-Sung; Han, Jung-Suk; Yang, Jae-Ho

    2008-11-01

    The aim of this study was to investigate the early bone response to the titanium dental implants with different surface characteristics using the rabbit tibia model. Calcium metaphosphate coated, anodic oxidized, hydroxyapatite particle-blasted, and turned (control) surfaces were compared. Surface topography was evaluated by field emission scanning electron microscope and optical interferometer. Eighteen rabbits received 72 implants in the tibia. Resonance frequency was analyzed every week for 6 weeks. Removal torque values were measured 2 and 6 weeks after placement. The implant-bone interfaces were directly observed by light microscope and bone-to-implant contact ratios were measured 2 and 6 weeks after insertion. All the surface-modified implants showed superior initial bone responses to the control. No significant differences were found among the surface-modified groups. Data suggest that various surface modification methods can provide favorable bone responses for early functioning and healing of dental implants.

  6. Comparion of stability in titanium implants with different surface topographies in dogs

    PubMed Central

    Kim, Nam-Sook; Vang, Mong-Sook; Park, Sang-Won; Park, Ha-Ok; Lim, Hyun-Pil

    2009-01-01

    STATEMENT OF PROBLEM A few of studies which compared and continuously measured the stability of various surface treated implants in the same individual had been performed. PURPOSE We aim to find the clinical significance of surface treatments by observing the differences in the stabilization stages of implant stability. MATERIAL AND METHODS Eight different surface topographies of dental implants were especially designed for the present study. Machined surface implants were used as a control group. 4 nano-treated surface implants (20 nm TiO2 coating surface, heat-treated 80 nm TiO2 coating surface, CaP coating surface, heat treated CaP coating surface) and 3 micro-treated surface implants [resorbable blast media (RBM) surface, sandblast and acid-etched (SAE) surface, anodized RBM surface] were used as experiment groups. All 24 implants were placed in 3 adult dogs. Periotest® & ISQ values measured for 8 weeks and all animals were sacrificed at 8 weeks after surgery. Then the histological analyses were done. RESULTS In PTV, all implants were stabilized except 1 failed implants. In ISQ values, The lowest stability was observed at different times for each individual. The ISQ values were showed increased tendency after 5 weeks in every groups. After 4 to 5 weeks, the values were stabilized. There was no statistical correlation between the ISQ values and PTV. In the histological findings, the bone formation was observed to be adequate in general and no differences among the 8 surface treated implants. CONCLUSIONS In this study, the difference in the stability of the implants was determined not by the differences in the surface treatment but by the individual specificity. PMID:21165255

  7. Production technology for high efficiency ion implanted solar cells

    NASA Technical Reports Server (NTRS)

    Kirkpatrick, A. R.; Minnucci, J. A.; Greenwald, A. C.; Josephs, R. H.

    1978-01-01

    Ion implantation is being developed for high volume automated production of silicon solar cells. An implanter designed for solar cell processing and able to properly implant up to 300 4-inch wafers per hour is now operational. A machine to implant 180 sq m/hr of solar cell material has been designed. Implanted silicon solar cells with efficiencies exceeding 16% AM1 are now being produced and higher efficiencies are expected. Ion implantation and transient processing by pulsed electron beams are being integrated with electrostatic bonding to accomplish a simple method for large scale, low cost production of high efficiency solar cell arrays.

  8. Tailoring biomaterial surface properties to modulate host-implant interactions: implication in cardiovascular and bone therapy

    PubMed Central

    Pacelli, Settimio; Manoharan, Vijayan; Desalvo, Anna; Lomis, Nikita; Jodha, Kartikeya Singh

    2016-01-01

    Host body response to a foreign medical device plays a critical role in defining its fate post implantation. It is thus important to control host-material interactions by designing innovative implant surfaces. In the recent years, biochemical and topographical features have been explored as main target to produce this new type of bioinert or bioresponsive implants. The review discusses specific biofunctional materials and strategies to achieve a precise control over implant surface properties and presents possible solutions to develop next generation of implants, particularly in the fields of bone and cardiovascular therapy. PMID:27630769

  9. Bone healing at implants with a fluoride-modified surface: an experimental study in dogs.

    PubMed

    Berglundh, T; Abrahamsson, I; Albouy, J-P; Lindhe, J

    2007-04-01

    The aim of the present experiment was to study early stages of osseointegration to implants with a fluoride-modified surface. Six mongrel dogs, about 1-year old, were used. All mandibular premolars and the first mandibular molars were extracted. Three months later, mucoperiosteal flaps were elevated in one side of the mandible and six sites were identified for implant placement. The control implants (MicroThread) had a TiOblast surface, while the test implants (OsseoSpeed) had a fluoride-modified TiOblast surface. Both types of implants had a similar geometry, a diameter of 3.5 mm and were 8 mm long. Following installation, cover screws were placed and the flaps were adjusted and sutured to cover all implants. Four weeks after the first implant surgery, the installation procedure was repeated in the opposite side of the mandible. Two weeks later, biopsies were obtained and prepared for histological analysis. The void that occurred between the cut bone wall of the recipient site and the macro-threads of the implant immediately following implant installation was used to study early bone formation. It was demonstrated that the amount of new bone that formed in the voids within the first 2 weeks of healing was larger at fluoride-modified implants (test) than at TiOblast (control) implants. It was further observed that the amount of bone-to-implant contact that had been established after 2 weeks in the macro-threaded portion of the implant was significantly larger at the test implants than at the controls. It is suggested that the fluoride-modified implant surface promotes osseointegration in the early phase of healing following implant installation.

  10. Creation of wear-resistant frictional surfaces by implanting materials based on tungsten carbide

    NASA Astrophysics Data System (ADS)

    Davidov, S. V.; Gorlenko, A. O.

    2017-02-01

    The influenceof the implanted tungsten carbide on the formation of wear-resistant structures, formed in the process of implementation of the combined electro-processing technology in the friction surfaces, is studied. It has been shown that during the thermal force influence in the deformation zone, there is intensive austenizationof the steel with the dissolution of the tungsten carbide powder and the subsequent formation of the composite nanostructures as a result of decomposition of the supercooled austenite, supersaturated with tungsten. The results of tribologicaltestings of cylindrical samples by the normalized method are presented.

  11. A cochlear implant fabricated using a bulk silicon-surface micromachining process

    NASA Astrophysics Data System (ADS)

    Bell, Tracy Elizabeth

    1999-11-01

    This dissertation presents the design and fabrication of two generations of a silicon microelectrode array for use in a cochlear implant. A cochlear implant is a device that is inserted into the inner ear and uses electrical stimulation to provide sound sensations to the profoundly deaf. The first-generation silicon cochlear implant is a passive device fabricated using silicon microprobe technology developed at the University of Michigan. It contains twenty-two iridium oxide (IrO) stimulating sites that are 250 mum in diameter and spaced at 750 mum intervals. In-vivo recordings were made in guinea pig auditory cortex in response to electrical stimulation with this device, verifying its ability to electrically evoke an auditory response. Auditory thresholds as low as 78 muA were recorded. The second-generation implant is a thirty-two site, four-channel device with on-chip CMOS site-selection circuitry and integrated position sensing. It was fabricated using a novel bulk silicon surface micromachining process which was developed as a part of this dissertation work. While the use of semiconductor technology offers many advantages in fabricating cochlear implants over the methods currently used, it was felt that even further advantages could be gained by developing a new micromachining process which would allow circuitry to be distributed along the full length of the cochlear implant substrate. The new process uses electropolishing of an n+ bulk silicon sacrificial layer to undercut and release n- epitaxial silicon structures from the wafer. An extremely abrupt etch-stop between the n+ and n- silicon is obtained, with no electropolishing taking place in the n-type silicon that is doped lower than 1 x 1017 cm-3 in concentration. Lateral electropolishing rates of up to 50 mum/min were measured using this technique, allowing one millimeter-wide structures to be fully undercut in as little as 10 minutes. The new micromachining process was integrated with a standard p

  12. Effectiveness of disinfection therapies and promotion of osteoblast growth on osseotite and nanotite implant surfaces.

    PubMed

    Lubin, Judith; Hernandez, Maria A; Drukteinis, Saulius E; Parker, William B; Murray, Peter E

    2014-08-01

    To evaluate the effectiveness of 4 procedures to disinfect implant surfaces intentionally inoculated with bacteria and afterward to evaluate osteoblast viability to the disinfected implant surfaces. Eighty-eight commercially pure Osseotite and Nanotite titanium implant discs were inoculated with Porphyromonas gingivalis. The implant surfaces were disinfected with EDTA, tetracycline, citric acid, or neodymium-doped yttrium aluminum garnet (Nd:YAG) laser. The implant discs were then placed in cultures of osteoblast cells. Osseotite implant discs were easier to disinfect compared with the Nanotite implant discs. Citric acid and tetracycline were the most effective solutions for the disinfection of P. gingivalis from the Osseotite implant discs. The Nanotite implant discs were the most difficult to disinfect, likely because of their chemical and physical properties. Citric acid and tetracycline were most effective for disinfecting the Osseotite implant discs, and further clinical research is needed to verify these effects in vivo. The Nd:YAG laser was the weakest disinfection method, and it is not recommended for disinfecting implant surfaces until its effectiveness is improved.

  13. Enhancing surface free energy and hydrophilicity through chemical modification of microstructured titanium implant surfaces.

    PubMed

    Rupp, F; Scheideler, L; Olshanska, N; de Wild, M; Wieland, M; Geis-Gerstorfer, J

    2006-02-01

    Roughness-induced hydrophobicity, well-known from natural plant surfaces and intensively studied toward superhydrophobic surfaces, has currently been identified on microstructured titanium implant surfaces. Studies indicate that microstructuring by sandblasting and acid etching (SLA) enhances the osteogenic properties of titanium. The undesired initial hydrophobicity, however, presumably decelerates primary interactions with the aqueous biosystem. To improve the initial wettability and to retain SLA microstructure, a novel surface modification was tested. This modification differs from SLA by its preparation after acid etching, which was done under protective gas conditions following liquid instead of dry storage. We hypothesized that this modification should have increased wettability due to the prevention of contaminations that occurs during air contact. The main outcome of dynamic wettability measurements was that the novel modification shows increased surface free energy (SFE) and increased hydrophilicity with initial water contact angles of 0 degrees compared to 139.9 degrees for SLA. This hydrophilization was kept even after any drying. Reduced hydrocarbon contaminations were identified to play a possible role in altered surface thermodynamics. Such surfaces aim to retain the hydrophilicity and natural high surface energy of the Ti dioxide surface until surgical implants' insertion and are compared in this in vitro study with structural surface variants of titanium to compare roughness and chemically induced wettability.

  14. Low-cost ion implantation and annealing technology for solar cells

    NASA Technical Reports Server (NTRS)

    Kirkpatrick, A. H.; Minnucci, J. A.; Greenwald, A. C.

    1980-01-01

    Ion implantation and thermal annealing techniques for processing junctions and back surface layers in solar cells are discussed. Standard 10 keV (31)p(+) junction implants and 25 keV (11)B(+) back surface implants in combination with three-step furnace annealing are used for processing a range of silicon materials and device structures. Cells with efficiencies up to 16.5% AM1 are being produced, and large-area terrestrial cells with implanted junctions and back fields being fabricated in pilot production exhibit average efficiencies in excess of 15% AM1. Thermal annealing methods for removal of the radiation damage caused by implantation should be replaced by transient processing techniques in future production. Design studies have been completed for solar cell processing implanters to support 10 MW/yr and 100 MW/yr production lines, and analyses indicate that implantation costs can be reduced to approximately 1 cent/watt.

  15. Low-cost ion implantation and annealing technology for solar cells

    NASA Technical Reports Server (NTRS)

    Kirkpatrick, A. H.; Minnucci, J. A.; Greenwald, A. C.

    1980-01-01

    Ion implantation and thermal annealing techniques for processing junctions and back surface layers in solar cells are discussed. Standard 10 keV (31)p(+) junction implants and 25 keV (11)B(+) back surface implants in combination with three-step furnace annealing are used for processing a range of silicon materials and device structures. Cells with efficiencies up to 16.5% AM1 are being produced, and large-area terrestrial cells with implanted junctions and back fields being fabricated in pilot production exhibit average efficiencies in excess of 15% AM1. Thermal annealing methods for removal of the radiation damage caused by implantation should be replaced by transient processing techniques in future production. Design studies have been completed for solar cell processing implanters to support 10 MW/yr and 100 MW/yr production lines, and analyses indicate that implantation costs can be reduced to approximately 1 cent/watt.

  16. Breast Implant-Associated Anaplastic Large Cell Lymphoma in Australia and New Zealand: High-Surface-Area Textured Implants Are Associated with Increased Risk.

    PubMed

    Loch-Wilkinson, Anna; Beath, Kenneth J; Knight, Robert John William; Wessels, William Louis Fick; Magnusson, Mark; Papadopoulos, Tim; Connell, Tony; Lofts, Julian; Locke, Michelle; Hopper, Ingrid; Cooter, Rodney; Vickery, Karen; Joshi, Preeti Avinash; Prince, H Miles; Deva, Anand K

    2017-10-01

    The association between breast implants and breast implant-associated anaplastic large cell lymphoma (ALCL) has been confirmed. Implant-related risk has been difficult to estimate to date due to incomplete datasets. All cases in Australia and New Zealand were identified and analyzed. Textured implants reported in this group were subjected to surface area analysis. Sales data from three leading breast implant manufacturers (i.e., Mentor, Allergan, and Silimed) dating back to 1999 were secured to estimate implant-specific risk. Fifty-five cases of breast implant-associated ALCL were diagnosed in Australia and New Zealand between 2007 and 2016. The mean age of patients was 47.1 years and the mean time of implant exposure was 7.46 years. There were four deaths in the series related to mass and/or metastatic presentation. All patients were exposed to textured implants. Surface area analysis confirmed that higher surface area was associated with 64 of the 75 implants used (85.3 percent). Biocell salt loss textured (Allergan, Inamed, and McGhan) implants accounted for 58.7 percent of the implants used in this series. Comparative analysis showed the risk of developing breast implant-associated ALCL to be 14.11 times higher with Biocell textured implants and 10.84 higher with polyurethane (Silimed) textured implants compared with Siltex textured implants. This study has calculated implant-specific risk of breast implant-associated ALCL. Higher-surface-area textured implants have been shown to significantly increase the risk of breast implant-associated ALCL in Australia and New Zealand. The authors present a unifying hypothesis to explain these observations.

  17. Relationship between surface properties (roughness, wettability and morphology) of titanium and dental implant removal torque.

    PubMed

    Elias, Carlos Nelson; Oshida, Yoshiki; Lima, José Henrique Cavalcanti; Muller, Carlos Alberto

    2008-07-01

    The biological properties of titanium depend on its surface oxide film. Several mechanical and chemical treatments have been used to modify the surface morphology and properties of titanium dental implants. One possible method of improving dental implant biocompatibility is to increase surface roughness and decrease the contact angle. In the present work, the biological properties of dental implants were investigated through in vivo and in vitro tests. The effects of surface roughness, contact angle and surface morphology on titanium dental implant removal torque were investigated. Machined dental implants and discs made with commercially pure titanium ASTM grade 4 were submitted to sandblasting treatments, acid etching and anodizing. The sample surface morphologies were characterized by SEM, the surface roughness parameters were quantified using a laser non-contact profilometer, and a contact angle measurement was taken. Dental implants were placed in the tibia of rabbits and removed 12 weeks after the surgery. It was found that: (i) acid etching homogenized the surface roughness parameters; (ii) the anodized surface presented the smallest contact angle; (iii) the in vivo test suggested that, in similar conditions, the surface treatment had a beneficial effect on the implant biocompatibility measured through removal torque; and (iv) the anodized dental implant presented the highest removal torque.

  18. Bioactive glass surface for fiber reinforced composite implants via surface etching by Excimer laser.

    PubMed

    Kulkova, Julia; Moritz, Niko; Huhtinen, Hannu; Mattila, Riina; Donati, Ivan; Marsich, Eleonora; Paoletti, Sergio; Vallittu, Pekka K

    2016-07-01

    Biostable fiber-reinforced composites (FRC) prepared from bisphenol-A-glycidyldimethacrylate (BisGMA)-based thermosets reinforced with E-glass fibers are promising alternatives to metallic implants due to the excellent fatigue resistance and the mechanical properties matching those of bone. Bioactive glass (BG) granules can be incorporated within the polymer matrix to improve the osteointegration of the FRC implants. However, the creation of a viable surface layer using BG granules is technically challenging. In this study, we investigated the potential of Excimer laser ablation to achieve the selective removal of the matrix to expose the surface of BG granules. A UV-vis spectroscopic study was carried out to investigate the differences in the penetration of light in the thermoset matrix and BG. Thereafter, optimal Excimer laser ablation parameters were established. The formation of a calcium phosphate (CaP) layer on the surface of the laser-ablated specimens was verified in simulated body fluid (SBF). In addition, the proliferation of MG63 cells on the surfaces of the laser-ablated specimens was investigated. For the laser-ablated specimens, the pattern of proliferation of MG63 cells was comparable to that in the positive control group (Ti6Al4V). We concluded that Excimer laser ablation has potential for the creation of a bioactive surface on FRC-implants. Copyright © 2016 IPEM. Published by Elsevier Ltd. All rights reserved.

  19. Ion-beam-sputter modification of the surface morphology of biological implants

    NASA Technical Reports Server (NTRS)

    Weigand, A. J.; Banks, B. A.

    1977-01-01

    The surface chemistry and texture of materials used for biological implants may significantly influence their performance and biocompatibility. Recent interest in the microscopic control of implant surface texture has led to the evaluation of ion-beam sputtering as a potentially useful surface roughening technique. Ion sources, similar to electron-bombardment ion thrusters designed for propulsive applications, are used to roughen the surfaces of various biocompatible alloys or polymer materials. These materials are typically used for dental implants, orthopedic prostheses, vascular prostheses, and artificial heart components. Masking techniques and resulting surface textures are described along with progress concerning evaluation of the biological response to the ion-beam-sputtered surfaces.

  20. Ion beam sputter modification of the surface morphology of biological implants

    NASA Technical Reports Server (NTRS)

    Weigand, A. J.; Banks, B. A.

    1976-01-01

    The surface chemistry and texture of materials used for biological implants may significantly influence their performance and biocompatibility. Recent interest in the microscopic control of implant surface texture has led to the evaluation of ion beam sputtering as a potentially useful surface roughening technique. Ion sources, similar to electron bombardment ion thrusters designed for propulsive applications, are used to roughen the surfaces of various biocompatible alloys or polymer materials. These materials are typically used for dental implants, orthopedic prostheses, vascular prostheses, and artificial heart components. Masking techniques and resulting surface textures are described along with progress concerning evaluation of the biological response to the ion beam sputtered surfaces.

  1. Ion-beam-sputter modification of the surface morphology of biological implants

    NASA Technical Reports Server (NTRS)

    Weigand, A. J.; Banks, B. A.

    1977-01-01

    The surface chemistry and texture of materials used for biological implants may significantly influence their performance and biocompatibility. Recent interest in the microscopic control of implant surface texture has led to the evaluation of ion-beam sputtering as a potentially useful surface roughening technique. Ion sources, similar to electron-bombardment ion thrusters designed for propulsive applications, are used to roughen the surfaces of various biocompatible alloys or polymer materials. These materials are typically used for dental implants, orthopedic prostheses, vascular prostheses, and artificial heart components. Masking techniques and resulting surface textures are described along with progress concerning evaluation of the biological response to the ion-beam-sputtered surfaces.

  2. Surface chemistry effects of topographic modification of titanium dental implant surfaces: 2. In vitro experiments.

    PubMed

    Cassinelli, Clara; Morra, Marco; Bruzzone, Giuseppe; Carpi, Angelo; Di Santi, Giuseppe; Giardino, Roberto; Fini, Milena

    2003-01-01

    To determine, in vitro, cytotoxicity and cell adhesion on 3 different implant surfaces. All samples had machined surfaces, but they were subjected to different cleaning procedures, which produced 3 different surface chemistries. One of the samples was "as-produced" from the machining tools. The other samples were subjected to partial and total cleaning routines. Cytotoxicity was evaluated using mouse fibroblast cultures, and cell adhesion was evaluated with osteoblast-like SaOS-2 cells. The "as-produced" sample showed a pronounced surface contamination by lubricating oils. For partially and totally cleaned samples, an increasing amount of titanium and a decreasing carbon/titanium ratio was observed as cleaning became more complete. Differences in surface chemistry such as those normally found on titanium implant surfaces (see part 1 of this series) can lead to those same effects which, in in vitro experiments, are normally accounted for in terms of surface topography alone. Effects related to surface chemistry can operate over and above surface topography, making it impossible, without proper characterization, to make definite statements about the role of topography alone.

  3. Surface and implantation effects on p-n junctions

    NASA Technical Reports Server (NTRS)

    Schacham, Samuel E.; Finkman, Eliezer

    1990-01-01

    The contribution of the graded region of implanted p-n junctions is analyzed using an exponential profile. Though previously neglected, it was recently shown that this contribution to the saturation current of HgCdTe diodes is significant. Assuming a dominant Auger recombination, an analytical solution to the continuity equation is obtained. An expression for the current generation by the graded region is presented for both ohmic and reflecting boundary conditions. A revised condition for a wide region is derived. When the region is narrow, the current differs drastically from that of the zero-gradient case. The effects of the junction depth and the substrate and surface concentrations on the current are investigated. It is shown that the reverse current does not saturate.

  4. Early bone apposition to hydrophilic and hydrophobic titanium implant surfaces: a histologic and histomorphometric study in minipigs.

    PubMed

    Vasak, Christoph; Busenlechner, Dieter; Schwarze, Uwe Y; Leitner, Herbert F; Munoz Guzon, Fernando; Hefti, Thomas; Schlottig, Falko; Gruber, Reinhard

    2014-12-01

    The first objective of this pilot study was to evaluate the impact of the hydrophilicity on the early phases of osseointegration. The second objective was to compare two hydrophilic implant surfaces with different geometries, surface roughness, and technologies achieving hydrophilicity. Twelve weeks after extraction, all four quadrants of nine minipigs received three dental implants, alternating between hydrophilic microrough surfaces (INICELL and SLActive) and a conventional hydrophobic microrough surface. After 5, 10, and 15 days of submerged healing, ground sections were prepared and subjected to histologic and histomorphometric analysis. The histologic analysis revealed a similar healing pattern among the hydrophilic and hydrophobic implant surfaces, with extensive bone formation occurring between day 5 and day 10. With BIC values of greater than 50% after 10 days, all examined surfaces indicated favorable osseointegration at this very early point in healing. At day 15, the mean new bone-to-implant contact (newBIC) of one hydrophilic surface (INICELL; 55.8 ± 14.4%) was slightly greater than that of the hydrophobic microrough surface (40.6 ± 20.2%). At day 10 and day 15, an overall of 21% of the implants had to be excluded from analysis due to inflammations primarily caused by surgical complications. Substantial bone apposition occurs between day 5 and day 10. The data suggest that the hydrophilic surface can provoke a slight tendency toward increased bone apposition in minipigs after 15 days. A direct comparison of two hydrophilic surfaces with varying geometries is of limited relevance. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  5. Resonance frequency analysis, insertion torque, and bone to implant contact of 4 implant surfaces: comparison and correlation study in sheep.

    PubMed

    Dagher, Maroun; Mokbel, Nadim; Jabbour, Gabriel; Naaman, Nada

    2014-12-01

    Primary stability is evaluated using resonance frequency analysis (RFA) and insertion torque (IT). Although there is a strong correlation between RFA and IT, studies failed to find a correlation between RFA and bone to implant contact (BIC) or IT and BIC. To compare RFA, IT, and BIC of SLA, SLActive, Euroteknika, and TiUnite implant surfaces and evaluate the correlation between them. Thirty-two implants were placed in 8 sheep. RFA and IT were recorded. Animals were killed at 1 and 2 months. A significant difference was found in RFA between the 4 surfaces. No significant difference was found for IT. Mean BIC was different between all 4 surfaces. A significant positive correlation was found between RFA and IT with SLA. No significant correlation was found between RFA and BIC and between IT and BIC at 1 and 2 months. Implants with 4 different surfaces have similar IT values but different RFA and BIC. Additionally irrespective of the implant surface, there is no correlation between IT and BIC and between RFA and BIC.

  6. Bone attachment to glass-fibre-reinforced composite implant with porous surface.

    PubMed

    Mattila, R H; Laurila, P; Rekola, J; Gunn, J; Lassila, L V J; Mäntylä, T; Aho, A J; Vallittu, P K

    2009-06-01

    A method has recently been developed for producing fibre-reinforced composites (FRC) with porous surfaces, intended for use as load-bearing orthopaedic implants. This study focuses on evaluation of the bone-bonding behaviour of FRC implants. Three types of cylindrical implants, i.e. FRC implants with a porous surface, solid polymethyl methacrylate (PMMA) implants and titanium (Ti) implants, were inserted in a transverse direction into the intercondular trabeculous bone area of distal femurs and proximal tibias of New Zealand White rabbits. Animals were sacrificed at 3, 6 and 12 weeks post operation, and push-out tests (n=5-6 per implant type per time point) were then carried out. At 12 weeks the shear force at the porous FRC-bone interface was significantly higher (283.3+/-55.3N) than the shear force at interfaces of solid PMMA/bone (14.4+/-11.0 N; p<0.001) and Ti/bone (130.6+/-22.2N; p=0.001). Histological observation revealed new bone growth into the porous surface structure of FRC implants. Solid PMMA and Ti implants were encapsulated mostly with fibrous connective tissue. Finite element analysis (FEA) revealed that porous FRC implants had mechanical properties which could be tailored to smooth the shear stress distribution at the bone-implant interface and reduce the stress-shielding effect.

  7. A contact mechanics model for ankle implants with inclusion of surface roughness effects

    NASA Astrophysics Data System (ADS)

    Hodaei, M.; Farhang, K.; Maani, N.

    2014-02-01

    Total ankle replacement is recognized as one of the best procedures to treat painful arthritic ankles. Even though this method can relieve patients from pain and reproduce the physiological functions of the ankle, an improper design can cause an excessive amount of metal debris due to wear, causing toxicity in implant recipient. This paper develops a contact model to treat the interaction of tibia and talus implants in an ankle joint. The contact model describes the interaction of implant rough surfaces including both elastic and plastic deformations. In the model, the tibia and the talus surfaces are viewed as macroscopically conforming cylinders or conforming multi-cylinders containing micrometre-scale roughness. The derived equations relate contact force on the implant and the minimum mean surface separation of the rough surfaces. The force is expressed as a statistical integral function of asperity heights over the possible region of interaction of the roughness of the tibia and the talus implant surfaces. A closed-form approximate equation relating contact force and minimum separation is used to obtain energy loss per cycle in a load-unload sequence applied to the implant. In this way implant surface statistics are related to energy loss in the implant that is responsible for internal void formation and subsequent wear and its harmful toxicity to the implant recipient.

  8. Development of vacuum arc ion sources for heavy ion accelerator injectors and ion implantation technology (invited)

    NASA Astrophysics Data System (ADS)

    Oks, Efim M.

    1998-02-01

    The status of experimental research and ongoing development and upgrade of MEVVA-type ion sources over the last two years since the previous ICIS-95 is reviewed. There are two main application fields for this ion source: heavy ion accelerators and material surface implantation technology. For particle accelerator ion injection to accelerators it is important to enhance the fractions of multiply charged ions in the ion beam as well as controlling the charge state distribution, and to improve of beam current stability (i.e., to minimize the beam noise) and pulse-to-pulse reproducibility. For ion implantation application we need to increase both the implantation dose rate and the source lifetime (between required maintenance downtime) as well as making this kind of source more reliable and of yet low cost. Most of experimental results reported on here have been obtained in a collaborative program between research groups LBNL (Berkeley, USA), GSI (Darmstadt, Germany), HCEI (Tomsk, Russia), and other important contributions have been made by the groups at (BNU, Beijing, China), EDU (Izmir, Turkey), and elsewhere.

  9. Energy Absorption in a Load-Unload Cycle of Knee Implant Using Fractal Model of Rough Surfaces

    NASA Astrophysics Data System (ADS)

    Hodaei, Mohammad; Farhang, Kambiz

    2016-05-01

    Roughness measurement of knee implant surfaces is investigated. The study of roughness measurement show that the topography of knee implant surface is multi-scale and surface spectra follows a power law behavior. A magnification of rough surface topography implies that there is no difference between original and magnified profile of implant surface. For implant surface, statistical parameters such as variance of height, curvature, and slope are found to be scale-dependent. Fractal representation of implant surface shows that the size-distribution of the multi-scale contacts spots follows a power law and is characterized by the fractal dimension of implant surface. Fractal surface description of the rough surfaces of knee implant is used to obtain force-displacement relationship of the contact force. Using an approximate function through the fusion of two piecewise functions, energy absorption of a knee implant in a single cycle of load-unload is obtained.

  10. Functional biocompatibility testing of silicone breast implants and a novel classification system based on surface roughness.

    PubMed

    Barr, S; Hill, E W; Bayat, A

    2017-06-27

    Increasing numbers of women undergo breast implantation for cosmetic and reconstructive purposes. Contracture of the fibrous capsule, which encases the implant leads to significant pain and reoperation. Texture, wettability and the cellular reaction to implant surfaces are poorly understood determinants of implant biocompatibility. The aim of this study was to evaluate the in-vitro characteristics of a range of commercial available implants using a macrophage based assay of implant biocompatibility and a quantitative assessment of wettability and texture. Thirteen commercially available surfaces were subjected to wettability and texture characterisation using scanning and laser confocal microscopy. THP-1 macrophages were cultured on their surfaces and assessed using Integrin αV immunocytochemistry, SEM and RT-PCR for the expression of TNF-Alpha, IL-6, IL-10 and a cytokine array for the production of TNF-alpha, IL-10, IL-1RA and IL1β; important indicators of inflammation and macrophage polarization. Textured surfaces can be accurately sub-categorized dependent upon roughness and re-entrant features into four main types (macro, micro, meso and nano-textured surfaces). Significant (P < 0.0001) differences in implant hydrophobicity and texture exist. Certain surfaces promoted poor macrophage polarization and an innate potential to foster a proinflammatory response. A subgroup analysis showed that texture had a variable effect on markers of inflammation in these surfaces. We propose a classification of implant surfaces based on roughness and present a macrophage based assay of breast implant biocompatibility with a quantitative assessment of implant wettability and texture. The breast implant surface-cell interaction is variable and sufficient to alter healing response and capsular contracture fate in-vivo. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  11. Computer technology applications in surgical implant dentistry: a systematic review.

    PubMed

    Tahmaseb, Ali; Wismeijer, Daniel; Coucke, Wim; Derksen, Wiebe

    2014-01-01

    To assess the literature on the accuracy and clinical performance of static computer-assisted implant surgery in implant dentistry. Electronic and manual literature searches were applied to collect information about (1) the accuracy and (2) clinical performance of static computer-assisted implant systems. Meta-regression analysis was performed to summarize the accuracy studies. Failure/complication rates were investigated using a generalized linear mixed model for binary outcomes and a logit link to model implant failure rate. From 2,359 articles, 14 survival and 24 accuracy studies were included in this systematic review. Nine different static image guidance systems were involved. The meta-analysis of the accuracy (24 clinical and preclinical studies) revealed a total mean error of 1.12 mm (maximum of 4.5 mm) at the entry point measured in 1,530 implants and 1.39 mm at the apex (maximum of 7.1 mm) measured in 1,465 implants. For the 14 included survival studies (total of 1,941 implants) using static computer-assisted implant dentistry, the mean failure rate was 2.7% (0% to 10%) after an observation period of at least 12 months. In 36.4% of the treated cases, intraoperative or prosthetic complications were reported, which included: template fractures during the surgery, change of plan because of factors such as limited primary implant stability, need for additional grafting procedures, prosthetic screw loosening, prosthetic misfit, and prosthesis fracture. Different levels of quantity and quality of evidence were available for static computer-assisted implant placement, with tight-fitting high implant survival rates after only 12 months of observation in different indications achieving a variable level of accuracy. Future long-term clinical data are necessary to identify clinical indications; detect accuracy; assess risk; and justify additional radiation doses, effort, and costs associated with computer-assisted implant surgery.

  12. New cochlear implant technologies improve performance in post-meningitic deaf patients.

    PubMed

    Mosnier, Isabelle; Felice, Andrea; Esquia, Gonzalo; Borel, Stéphanie; Bouccara, Didier; Ambert-Dahan, Emmanuèle; Smadja, Martine; Ferrary, Evelyne; Sterkers, Olivier

    2013-01-01

    The objective of the study was to compare the performance of cochlear implantation between post-meningitic and non-meningitic patients, and to evaluate the impact on hearing outcome of technical advances in cochlear implant technology. Retrospective chart review was used as the study design. Twenty adults with post-meningitic profound hearing loss receiving unilateral or bilateral cochlear implants between 1990 and 2008 were tested. Results were compared to a control group of 46 adults implanted for a non-meningitic hearing loss, with the same pre-operative speech scores. Speech scores were poorer in post-meningitic patients compared to those of control group, whatever the duration after implantation (p < 0.0001). Speech scores of subjects implanted and fitted before 2001 were compared to those of subjects implanted after 2001, with the same duration of hearing loss. Performance improved with implants and processors available after 2001, with a magnitude of improvement higher in post-meningitic patients (p < 0.0001 and p < 0.05 in post-meningitic and control groups, respectively, two-way ANOVA). Consequently, speech scores of post-meningitic patients implanted after 2001 achieved those of control subjects (two-way ANOVA). Advances in cochlear implant technology and coding strategy improve hearing outcome in post-meningitic adult patients, who now achieve similar performance as those of non-meningitic patients.

  13. Surface analytical studies of maxillofacial implants: influence of the preoperational treatment and the human body on the surface properties of retrieved implants.

    PubMed

    Kiss, Gábor; Sebők, Béla; Szabó, Péter J; Joób, Arpád F; Szabó, György

    2014-05-01

    In the present work, surface analytical investigation of unimplanted as well as retrieved pyrolytic carbon-covered carbon/carbon composite implants and Ti osteosynthesis plates is reported. The Ti plates were covered by a 200-nm-thick, anodically and thermally formed TiO2 layer. Our results suggest that although the oxide layer on the Ti miniplates remained stable during the time spent in the human body, there is still material transport between the implant and the human body. In case of the carbon/carbon composite implants, damage of the carbon fibers constituting the material was found on one side of the sterile implant and attributed to the manufacturing process. The NaCl crystals originally present on the surface of the sterile material disappeared during the time spent in the human body. As a result of the interaction with the human body, a new surface layer (mainly constituted of carbon) appeared on the implant. The results indicate that both the time spent in the human organism and the preparation of the implants before operation can have detectable effects on the investigated surface properties. Surface analytical investigations could therefore provide information not only about the biocompatibility of these materials but also about the effect of their treatment before operation.

  14. Surface analysis of 2 orthodontic mini-implants after clinical use.

    PubMed

    Marigo, Guilherme; Elias, Carlos Nelson; Marigo, Marcelo

    2016-07-01

    The purpose of this study was to analyze the design and surface morphology of 2 brands of mini-implants before and after 12 to 18 months of clinical use. We studied 22 mini-implants sold in the Brazilian market by 2 companies (Forestadent, Pforzheim, Germany; and Dental Morelli, Sorocaba, São Paulo, Brazil). The surface morphology of the mini-implants was analyzed by scanning electron microscopy before and after insertion in the oral environment to aid orthodontic movement. The Forestadent and the Morelli mini-implants showed different shapes (size, screw thread design), and the surface morphology changed after clinical use. The most important surface morphology alterations after clinical use were strain in several parts and fracture of the active thread part of some mini-implants. The results of the analyses showed that the screw threads of the mini-implants differ in pitch, angle, and length. The mini-implants also showed differences in body design, active tip, and taper. These differences affect the performance of the mini-implants. After clinical use, all mini-implants showed surface degradation, plastic deformation, and some fractures. Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

  15. Early detachment of titanium particles from various different surfaces of endosseous dental implants.

    PubMed

    Franchi, M; Bacchelli, B; Martini, D; Pasquale, V De; Orsini, E; Ottani, V; Fini, M; Giavaresi, G; Giardino, R; Ruggeri, A

    2004-05-01

    Titanium (Ti) endosseous dental screws with different surfaces (smooth titanium--STi, titanium plasma-sprayed-TPS, alumina oxide sandblasted and acid-etched--Al-SLA, zirconium oxide sandblasted and acid etched--Zr-SLA) were implanted in femura and tibiae of sheep to investigate the biological evolution of the peri-implant tissues and detachment of Ti debris from the implant surfaces in early healing. Implants were not loaded. Sections of the screws and the peri-implant tissues obtained by sawing and grinding were analysed by light microscopy immediately after implantation (time 0) and after 14 days. All samples showed new bone trabeculae and vascularised medullary spaces in those areas where gaps between the implants and host bone were visible. In contrast, no osteogenesis was induced in the areas where the implants were initially positioned in close contact with the host bone. Chips of the pre-existing bone inducing new peri-implant neo-osteogenesis were surrounded by new bone trabeculae. The threads of some screws appeared to be deformed where the host bone showed fractures. Ti granules of 3-60 microm were detectable only in the peri-implant tissues of TPS implants both immediately after surgery and after 14 days, thus suggesting that this phenomenon may be related to the friction of the TPS coating during surgical insertion.

  16. Osteointegration of a modular metal-polyethylene surface gliding finger implant: a case report.

    PubMed

    Schindele, Stephan F; Sprecher, Christoph M; Milz, Stefan; Hensler, Stefanie

    2016-09-01

    Primary press fit and secondary osteointegration is a precondition for component anchoring in articular surface replacements, also in the case of proximal interphalangeal (PIP) joint. Nevertheless, many existing prostheses for the PIP joint have failed to show sufficient osteointegration. CapFlex-PIP(©) implant is a modular metal-polyethylene surface replacement for the PIP joint consisting of a proximal and distal component each having a titanium pore backside, which allows secondary osteointegration at the bone-implant interface. To evaluate osseous integration of this implant, we report a histological analysis of an explantation of a CapFlex-PIP(©) finger implant. We present a case of a removed CapFlex-PIP(©) implant due to a soft tissue complication in an 84-year-old woman. The patient received bisphosphonate medication as treatment for osteoporosis. For the histological analysis, the bone-implant contact (BIC) was measured on all stained sections using a Zeiss Axioplan microscope. The summated BIC was 40.7 % for the proximal component and 46.5 % for the distal component of the implant. Histology showed that the implant was in direct contact with the bone at various locations, with no signs of wear or degradation. This case demonstrates successful osteointegration of the CapFlex-PIP(©) implant. Both components of the investigated implant show osseous integration to an extent which is comparable to that of other load-bearing and articulating implants at different locations in the human body.

  17. Evaluation of Implant Collar Surfaces for Marginal Bone Loss: A Systematic Review and Meta-Analysis

    PubMed Central

    2016-01-01

    Background. It is important to understand the influence of different collar designs on peri-implant marginal bone loss, especially in the critical area. Objectives. The purpose of the present systematic review and meta-analysis was to compare dental implants with different collar surfaces, evaluating marginal bone loss and survival rates of implants. Methods. Eligibility criteria included clinical human studies, randomized controlled trials, and prospective and retrospective studies, which evaluated dental implants with different collar surface in the same study. Results. Twelve articles were included, with a total of 492 machined, 319 rough-surfaced, and 352 rough-surfaced microthreaded neck implants. There was less marginal bone loss at implants with rough-surfaced and rough-surfaced microthreaded neck than at machined-neck implants (difference in means: 0.321, 95% CI: 0.149 to 0.493; p < 0.01). Conclusion. Rough and rough-surfaced microthreaded implants are considered a predictable treatment for preserving early marginal bone loss. PMID:27493957

  18. In vitro studies on the effect of cleaning methods on different implant surfaces.

    PubMed

    Augthun, M; Tinschert, J; Huber, A

    1998-08-01

    The effect of specific cleaning procedures was examined on the surfaces of 3 implant types with different coatings and shapes (plasma sprayed [PS]; hydroxyapatite coated [HA] implants; and smooth titanium surface screws) using a scanning electron microscope. Each implant was treated for 60 seconds per instrument with one of 6 different hygiene measures: plastic curet, metal curet, diamond polishing device, ultrasonic scaler, air-powder-water spray with sodium hydrocarbonate solution, and chlorhexidine 0.1% solution rinse. The air-powder-abrasive system, chlorhexidine rinse, and curettage with a plastic instrument caused little or no surface damage in all but the hydroxyapatite-coated fixtures. Therefore, these 3 methods were tested to determine their cleaning efficacy in a second clinical study, which did not include the HA-coated fixture. Two implants were placed on the facial aspects of both upper molar regions using individual acrylic plates. Thus, 2 fixtures on each side were examined in each patient. The examination revealed that only the sodium hydrocarbonate spray yielded a clean fixture without damage to the implant surface. In a third stage, which imitated the clinical procedure of the second approach, the cell growth of mouse-fibroblasts on implant surfaces was examined after cleaning the surface with plastic scaler and the air-abrasive system, which represents the least damaging and most effective methods. In contrast to the implant surfaces treated with plastic scalers, mostly vital cells were found on implants sprayed with the air-abrasive system.

  19. Structural phase states in nickel-titanium surface layers doped with silicon by plasma immersion ion implantation

    NASA Astrophysics Data System (ADS)

    Kashin, Oleg A.; Lotkov, Aleksandr I.; Kudryashov, Andrey N.; Krukovsky, Konstantin V.; Ostapenko, Marina G.; Neiman, Alexey A.; Borisov, Dmitry P.

    2015-10-01

    The paper reports on a study of NiTi-based alloys used for manufacturing self-expanding intravascular stents to elucidate how the technological modes of plasma immersion ion implantation with silicon influence the chemical and phase composition of their surface layers. It is shown that two types of surface structure can be obtained depending on the mode of plasma immersion implantation: quasi-amorphous Si coating and Si-doped surface layer. The Si-doped surface layer contains new phases: a phase structured as the main B2 phase of NiTi but with a lower lattice parameter, R phase, and phase of highly dispersed SiO2 precipitates.

  20. Plasma assisted surface coating/modification processes - An emerging technology

    NASA Technical Reports Server (NTRS)

    Spalvins, T.

    1987-01-01

    A broad understanding of the numerous ion or plasma assisted surface coating/modification processes is sought. An awareness of the principles of these processes is needed before discussing in detail the ion nitriding technology. On the basis of surface modifications arising from ion or plasma energizing and interactions, it can be broadly classified as deposition of distinct overlay coatings (sputtering-dc, radio frequency, magnetron, reactive; ion plating-diode, triode) and surface property modification without forming a discrete coating (ion implantation, ion beam mixing, laser beam irradiation, ion nitriding, ion carburizing, plasma oxidation. These techniques offer a great flexibility and are capable in tailoring desirable chemical and structural surface properties independent of the bulk properties.

  1. Plasma assisted surface coating/modification processes: An emerging technology

    NASA Astrophysics Data System (ADS)

    Spalvins, T.

    A broad understanding of the numerous ion or plasma assisted surface coating/modification processes is sought. An awareness of the principles of these processes is needed before discussing in detail the ion nitriding technology. On the basis of surface modifications arising from ion or plasma energizing and interactions, it can be broadly classified as deposition of distinct overlay coatings (sputtering-dc, radio frequency, magnetron, reactive; ion plating-diode, triode) and surface property modification without forming a discrete coating (ion implantation, ion beam mixing, laser beam irradiation, ion nitriding, ion carburizing, plasma oxidation). These techniques offer a great flexibility and are capable in tailoring desirable chemical and structural surface properties independent of the bulk properties.

  2. Plasma assisted surface coating/modification processes - An emerging technology

    NASA Astrophysics Data System (ADS)

    Spalvins, T.

    A broad understanding of the numerous ion or plasma assisted surface coating/modification processes is sought. An awareness of the principles of these processes is needed before discussing in detail the ion nitriding technology. On the basis of surface modifications arising from ion or plasma energizing and interactions, it can be broadly classified as deposition of distinct overlay coatings (sputtering-dc, radio frequency, magnetron, reactive; ion plating-diode, triode) and surface property modification without forming a discrete coating (ion implantation, ion beam mixing, laser beam irradiation, ion nitriding, ion carburizing, plasma oxidation. These techniques offer a great flexibility and are capable in tailoring desirable chemical and structural surface properties independent of the bulk properties.

  3. Plasma assisted surface coating/modification processes - An emerging technology

    NASA Technical Reports Server (NTRS)

    Spalvins, T.

    1987-01-01

    A broad understanding of the numerous ion or plasma assisted surface coating/modification processes is sought. An awareness of the principles of these processes is needed before discussing in detail the ion nitriding technology. On the basis of surface modifications arising from ion or plasma energizing and interactions, it can be broadly classified as deposition of distinct overlay coatings (sputtering-dc, radio frequency, magnetron, reactive; ion plating-diode, triode) and surface property modification without forming a discrete coating (ion implantation, ion beam mixing, laser beam irradiation, ion nitriding, ion carburizing, plasma oxidation. These techniques offer a great flexibility and are capable in tailoring desirable chemical and structural surface properties independent of the bulk properties.

  4. Plasma assisted surface coating/modification processes: An emerging technology

    NASA Technical Reports Server (NTRS)

    Spalvins, T.

    1986-01-01

    A broad understanding of the numerous ion or plasma assisted surface coating/modification processes is sought. An awareness of the principles of these processes is needed before discussing in detail the ion nitriding technology. On the basis of surface modifications arising from ion or plasma energizing and interactions, it can be broadly classified as deposition of distinct overlay coatings (sputtering-dc, radio frequency, magnetron, reactive; ion plating-diode, triode) and surface property modification without forming a discrete coating (ion implantation, ion beam mixing, laser beam irradiation, ion nitriding, ion carburizing, plasma oxidation). These techniques offer a great flexibility and are capable in tailoring desirable chemical and structural surface properties independent of the bulk properties.

  5. Histomorphometry and stability analysis of early loaded implants with two different surface conditions in beagle dogs

    PubMed Central

    Kim, Dong-Seok; Kim, Dae-Gon; Park, Chan-Jin

    2009-01-01

    STATEMENT OF PROBLEM Despite an improved bone reactions of Mg-incorporated implants in the animals, little yet has been carried out by the experimental investigations in functional loading conditions. PURPOSE This study investigated the clinical and histologic parameters of osseointegrated Mg-incorporated implants in early loading conditions. MATERIAL AND METHODS A total of 36 solid screw implants (diameter 3.75 mm, length 10 mm) were placed in the mandibles of 6 beagle dogs. Test groups included 18 Mg-incorporated implants. Turned titanium implants served as control. Gold crowns were inserted 4 weeks after implant placement and the dogs were immediately put on a food diet. Implants were observed for 10 weeks after loading. Radiographic assessments and stability tests were performed at the time of fixture installation, 2nd stage surgery, 4 weeks after loading, and 10 weeks after loading. Histological observations and morphometrical measurements were also performed. RESULTS Of 36 implants, 33 displayed no discernible mobility, corresponding to successful clinical function. There was no statistically significant difference between test implants and controls in marginal bone levels (P = .46) and RFA values. The mean BIC% in the Mg-implants was 54.5 ± 8.4%. The mean BIC% in the turned implant was 45.3 ± 12.2%. These differences between the Mg-implant and control implant were statistically significant (P = .005). CONCLUSIONS The anodized, Mg-incorporated implant demonstrated significantly more bone-to-implant contact (BIC) in early loading conditions. CLINICAL IMPLICATIONS The results of this study in beagle dogs suggest the possibility of achieving predictable stability of early loaded free-standing dental implants with Mg-incorporated surface. PMID:21165249

  6. A Review on the Wettability of Dental Implant Surfaces: Theoretical and Experimental Aspects

    PubMed Central

    Rupp, Frank; Gittens, Rolando A.; Scheideler, Lutz; Marmur, Abraham; Boyan, Barbara D.; Schwartz, Zvi; Geis-Gerstorfer, Jürgen

    2014-01-01

    The surface wettability of biomaterials determines the biological cascade of events at the biomaterial/host interface. Wettability is modulated by surface characteristics, such as surface chemistry and surface topography. However, the design of current implant surfaces focuses mainly on specific micro- and nanotopographical features and is still far from predicting the concomitant wetting behavior. There is an increasing interest in understanding the wetting mechanisms of implant surfaces and the role of wettability on the biological response at the implant/bone or implant/soft tissue interface. Fundamental knowledge related to the influence of surface roughness (i.e., a quantification of surface topography) on titanium and titanium alloy surface wettability, and the different associated wetting regimes, can improve our understanding of the role of wettability of rough implant surfaces on the biological outcome. Such an approach has been applied to biomaterial surfaces only in a limited way. Focusing on titanium dental and orthopaedic implants, the present study reviews the current knowledge on the wettability of biomaterial surfaces, encompassing basic and applied aspects that include measurement techniques, thermodynamic aspects of wetting, and models predicting topographical and roughness effects on the wetting behavior. PMID:24590162

  7. A review on the wettability of dental implant surfaces I: theoretical and experimental aspects.

    PubMed

    Rupp, Frank; Gittens, Rolando A; Scheideler, Lutz; Marmur, Abraham; Boyan, Barbara D; Schwartz, Zvi; Geis-Gerstorfer, Jürgen

    2014-07-01

    The surface wettability of biomaterials determines the biological cascade of events at the biomaterial/host interface. Wettability is modulated by surface characteristics, such as surface chemistry and surface topography. However, the design of current implant surfaces focuses mainly on specific micro- and nanotopographical features, and is still far from predicting the concomitant wetting behavior. There is an increasing interest in understanding the wetting mechanisms of implant surfaces and the role of wettability in the biological response at the implant/bone or implant/soft tissue interface. Fundamental knowledge related to the influence of surface roughness (i.e. a quantification of surface topography) on titanium and titanium alloy surface wettability, and the different associated wetting regimes, can improve our understanding of the role of wettability of rough implant surfaces on the biological outcome. Such an approach has been applied to biomaterial surfaces only in a limited way. Focusing on titanium dental and orthopaedic implants, the present study reviews the current knowledge on the wettability of biomaterial surfaces, encompassing basic and applied aspects that include measurement techniques, thermodynamic aspects of wetting and models predicting topographical and roughness effects on the wetting behavior.

  8. Peri-implant conditions around sintered porous-surfaced (SPS) implants. A 36-month prospective cohort study.

    PubMed

    Malchiodi, Luciano; Ghensi, Paolo; Cucchi, Alessandro; Pieroni, Stefano; Bertossi, Dario

    2015-02-01

    The specific aim of this study was to assess sintered porous-surfaced (SPS) implant system from a biological point of view, through a prospective study of the health status and the evolution of the peri-implant tissues over time and analysis of the changes observed in the various peri-implant parameters. Hundred and fifty-one patients were treated consecutively from 2005 to 2007 using 280 SPS implants, which were restored with a single crown or a partial fixed denture. To accurately monitor the health and biological evolution of peri-implant soft and hard tissues, a number of clinical parameters were adopted, such as the modified Plaque Index (mPI), the modified sulcus Bleeding Index (mBI), Peri-implant Probing Depth (PPD), and Crestal Bone Level (CBL). Clinical and radiographic examinations were scheduled over a 36-month follow-up of functional loading according to a well-established protocol generally applied to determine implant success rates and Peri-implant Bone Loss (PBL). Statistical analysis was used to determine any significant differences or correlations (P = 0.05). A total of 259 SPS implants in 136 patients were followed up for 36 months. According to Buser's success criteria, the overall implant-based success rate was 98.1% and the mean PBL was 0.48 ± 0.29 mm. MBI and mPI mean values showed statistically significant differences between baseline and follow-up analyses (P < 0.001). No statistically significant differences in mean PPD values were found between baseline and control analyses (P = 0.060). This prospective cohort study revealed that the biological behavior of SPS implant system was characterized by high tissue stability during the observation period, both as regards soft and hard tissues. In particular, the crestal bone remodeling pattern was very similar to that reported in other studies, confirming that the bone loss around SPS implants, at least at 36 months, seems to be predictable. © 2014 John Wiley & Sons A/S. Published by John Wiley

  9. High Density Ion Implanted Contiguous Disk Bubble Technology

    DTIC Science & Technology

    1989-03-31

    regions. The flux from this stripe domain will intercept the magnetodiodes as shown in figure 1-12, and the Lorentz force (F = qv x B) will act on the...Following the propagation implant, the photoresist implant mask is removed with an air plasma in a barrel etcher. A 0.15,rm plasma SiO 2 layer is then

  10. Histomorphometric and histologic evaluation of titanium-zirconium (aTiZr) implants with anodized surfaces.

    PubMed

    Sharma, Ajay; McQuillan, A James; Shibata, Yo; Sharma, Lavanya A; Waddell, John Neil; Duncan, Warwick John

    2016-05-01

    The choice of implant surface has a significant influence on osseointegration. Modification of TiZr surface by anodization is reported to have the potential to modulate the osteoblast cell behaviour favouring more rapid bone formation. The aim of this study is to investigate the effect of anodizing the surface of TiZr discs with respect to osseointegration after four weeks implantation in sheep femurs. Titanium (Ti) and TiZr discs were anodized in an electrolyte containing DL-α-glycerophosphate and calcium acetate at 300 V. The surface characteristics were analyzed by scanning electron microscopy, electron dispersive spectroscopy, atomic force microscopy and goniometry. Forty implant discs with thickness of 1.5 and 10 mm diameter (10 of each-titanium, titanium-zirconium, anodized titanium and anodized titanium-zirconium) were placed in the femoral condyles of 10 sheep. Histomorphometric and histologic analysis were performed 4 weeks after implantation. The anodized implants displayed hydrophilic, porous, nano-to-micrometer scale roughened surfaces. Energy dispersive spectroscopy analysis revealed calcium and phosphorous incorporation into the surface of both titanium and titanium-zirconium after anodization. Histologically there was new bone apposition on all implanted discs, slightly more pronounced on anodised discs. The percentage bone-to-implant contact measurements of anodized implants were higher than machined/unmodified implants but there was no significant difference between the two groups with anodized surfaces (P > 0.05, n = 10). The present histomorphometric and histological findings confirm that surface modification of titanium-zirconium by anodization is similar to anodised titanium enhances early osseointegration compared to machined implant surfaces.

  11. The Influence of Implant Abutment Surface Roughness and the Type of Cement on Retention of Implant Supported Crowns

    PubMed Central

    Reddy, M. Sushender; Reddy, C. Rajaneesh; Pithani, Padmaja; R, Santosh Kumar; Kulkarni, Ganesh

    2015-01-01

    Objectives: To provide relative data on the retentive characters of the commonly used cements on different implant abutment surfaces. Materials and Methods: A total of 20 implant abutments were divided into 2 groups. Ten implants were unaltered and ten were air borne particle abraded with 50μ aluminium oxide. Three luting agents (Tempbond, IRM and ImProv) were used to secure the crowns to abutments. All the crowns were removed from the abutment with an Instron machine at 0.5mm per minute and tensile bond strengths were recorded. Statistical analysis was performed using Anova, Paired t-test and Post-Hoc tests. Results: IRM showed the highest mean tensile strength among the three cements when used with treated and untreated implant abutment surfaces. Change in the abutment surface roughness had no effect on the mean tensile bond strength of TempBond and IRM cements, whereas ImProv cement showed reduced tensile strength with sandblasted surface. Conclusion: When increased retention is required IRM cement with either sandblasted or milled surface could be used and when retrievability is required cements of choice could be either TempBond or ImProv. PMID:25954694

  12. Science and technology of biocompatible thin films for implantable biomedical devices.

    SciTech Connect

    Li, W.; Kabius, B.; Auciello, O.; Materials Science Division

    2010-01-01

    This presentation focuses on reviewing research to develop two critical biocompatible film technologies to enable implantable biomedical devices, namely: (1) development of bioinert/biocompatible coatings for encapsulation of Si chips implantable in the human body (e.g., retinal prosthesis implantable in the human eye) - the coating involves a novel ultrananocrystalline diamond (UNCD) film or hybrid biocompatible oxide/UNCD layered films; and (2) development of biocompatible films with high-dielectric constant and microfabrication process to produce energy storage super-capacitors embedded in the microchip to achieve full miniaturization for implantation into the human body.

  13. Adaptation of NASA technology for the optimization of orthopedic knee implants

    NASA Technical Reports Server (NTRS)

    Saravanos, D. A.; Mraz, P. J.; Hopkins, D. A.

    1991-01-01

    The NASA technology originally developed for the optimization of composite structures (engine blades) is adapted and applied to the optimization of orthopedic knee implants. A method is developed enabling the tailoring of the implant for optimal interaction with the environment of the tibia. The shape of the implant components are optimized, such that the stresses in the bone are favorably controlled to minimize bone degradation and prevent failures. A pilot tailoring system is developed and the feasibility of the concept is elevated. The optimization system is expected to provide the means for improving knee prosthesis and individual implant tailoring for each patient.

  14. Surgical Treatment of Severe Peri-Implantitis Using a Round Titanium Brush for Implant Surface Decontamination: A Case Report With Clinical Reentry.

    PubMed

    An, Yin-Zhe; Lee, Jae-Hong; Heo, Young-Ku; Lee, Jung-Seok; Jung, Ui-Won; Choi, Seong-Ho

    2017-06-01

    The most common cause of peri-implantitis is the accumulation of plaque and the formation of a biofilm on the implant surface. Terminating the development of the disease requires the biofilm to be removed from the implant surface. This paper describes 2 cases of severe peri-implantitis lesions treated through surgical approaches. Complete mechanical debridement with a round titanium brush was mainly performed to detoxify and modify the affected implant surface. A regenerative approach was then performed. In both cases, the surgical procedure was effective in arresting the peri-implantitis, and clinical reentry revealed uneventful healing of the existing bone defect. No further radiographic bone loss was observed over the 2-year follow-up period. This technique has the advantage of effective cleaning the contaminated implant surface, producing positive clinical and radiological results. However, further studies involving more cases are necessary to verify the reliability and validity of this technique.

  15. Prediction of lubrication regimes in wrist implants with spherical bearing surfaces.

    PubMed

    Pylios, T; Shepherd, D E T

    2004-03-01

    The wrist joint is frequently affected by rheumatoid arthritis, resulting in wrist pain, deformity and ultimately loss of function. Artificial wrist implants have been introduced to treat the rheumatoid wrist, to attempt to alleviate pain and restore some function to the joint. The aim of this study was to predict the likely lubrication regimes that occur in wrist implants with spherical bearing surfaces. The implant was modelled as an equivalent ball-on-plane. Elastohydrodynamic lubrication theory was used to determine the minimum film thickness for the implant under different load, entraining velocity, lubricant viscosity, size of implant and material combinations. The results show that the highest film thickness is found in large implants, with high viscosity, high entraining velocity and low load. Hard-on-soft material combinations will operate with a boundary lubrication regime. Material combinations involving ceramic bearing surfaces have the potential to operate with a mixed lubrication regime.

  16. Influence of Thickness and Contact Surface Geometry of Condylar Stem of TMJ Implant on Its Stability

    NASA Astrophysics Data System (ADS)

    Arabshahi, Zohreh; Kashani, Jamal; Kadir, Mohammed Rafiq Abdul; Azari, Abbas

    The aim of this study is to examine the effect thickness and contact surface geometry of condylar stem of TMJ implant on its stability in total reconstruction system and evaluate the micro strain resulted in bone at fixation screw holes in jaw bone embedded with eight different designs of temporomandibular joint implants. A three dimensional model of a lower mandible of an adult were developed from a Computed Tomography scan images. Eight different TMJ implant designs and fixation screws were modeled. Three dimensional finite element models of eight implanted mandibles were analyzed. The forces assigned to the masticatory muscles for incisal clenching were applied consisting of nine important muscular loads. In chosen loading condition, The results indicated that the anatomical curvature contact surface design of TMJ implant can moderately improve the stability and the strain resulted in fixation screw holes in thinner TMJ implant was diminished in comparison with other thicknesses.

  17. Effects of the Er:YAG laser irradiation on titanium implant materials and contaminated implant abutment surfaces.

    PubMed

    Matsuyama, Tomoko; Aoki, Akira; Oda, Shigeru; Yoneyama, Takayuki; Ishikawa, Isao

    2003-02-01

    The purpose of this study was to examine the morphological changes and temperature increases of the titanium after Er:YAG laser irradiation, and also to investigate the effect of this laser on debridement of contaminated healing abutments. Mechanical instruments have been used for the cleaning of implant abutment surfaces, however, most of them are not appropriate for the application to titanium surface. Recently, the Er:YAG laser has been expected to have a promising ability for the debridement of implant surface. Experiments were composed of three parts. At first, ten titanium round plates were exposed to the Er:YAG laser irradiation at 30-200 mJ/pulse and the surface changes were observed by stereomicroscope and scanning electron microscope. Secondly, the surface temperature changes of 60 titanium plates during and after Er:YAG laser irradiation at 30 and 50 mJ/pulse were measured by thermographic equipment. At last, calculus on the surface of six contaminated healing abutments was removed by Er:YAG laser or ultrasonic scaler, and the treated surfaces were examined by stereomicroscope. Under 50 mJ/pulse, distinct morphological changes were not observed and the elevation of surface temperature was minimal, especially in the use of water-cooling. The Er:YAG laser at 30 mJ/pulse and 30 Hz with water spray was capable of effectively removing plaque and calculus on the implant abutments without injuring their surfaces. This study indicates that the Er:YAG laser can be a novel technical modality for the debridement of implant abutment surface.

  18. Advanced Technologies for Determination of Surface Cleanliness

    NASA Astrophysics Data System (ADS)

    Kudlacek, Jan; Chabera, Petr

    2014-12-01

    For high utility value of products is significant quality of surface treatment. Among the processes that most affect the quality of surface treatment are mainly surface pretreatment processes, namely processes of cleaning (degreasing). This article is devoted to quality control after surface pre-treatment. It mainly deals with the modern method for detecting surface contamination grease based on fluorescence methods. Impurities such as grease, oil and other have characteristic fluorescence after illumination by UV source. This principle can be used to determine the purity of the substrate surface, thereby ensuring the quality of the surface. Surface cleanliness is very important factor for the correct application of subsequent technological processes.

  19. Detoxification of Implant Surfaces Affected by Peri-Implant Disease: An Overview of Non-surgical Methods

    PubMed Central

    Valderrama, Pilar; Blansett, Jonathan A; Gonzalez, Mayra G; Cantu, Myrna G; Wilson, Thomas G

    2014-01-01

    Objective: The aim of this review is to summarize the findings of studies that have evaluated non-surgical approaches for detoxification of implant body surfaces in vitro and in vivo, and to evaluate clinical trials on the use of these methodologies for treating peri-implant disease. Materials and methods: A literature search was conducted using MEDLINE (Pubmed) from 1966 to 2013. In vitro and in vivo studies as well as clinical trials on non-surgical therapy were evaluated. The outcome variables were the ability of the therapeutic method to eliminate the biofilm and endotoxins from the implant surface, the changes in clinical parameters including probing depth, clinical attachment levels, bleeding on probing; radiographic bone fill and histological re-osseointegration. Results: From 134 articles found 35 were analyzed. The findings, advantages and disadvantages of using lasers as well as mechanical and chemical methods are discussed. Most of the in vivo and human studies used combination therapies which makes determining the efficacy of one specific method difficult. Most human studies are case series with short term longitudinal analysis without survival or failure reports. Conclusion: Complete elimination of the biofilms is difficult to achieve using these approaches. All therapies induce changes of the chemical and physical properties of the implant surface. Re-osseointegration may be difficult to achieve if not impossible without surgical access to ensure thorough debridement of the defect and detoxification of the implant surface. Combination protocols for non-surgical treatment of peri-implantitis in humans have shown some positive clinical results but long-term evaluation to evaluate the validity and reliability of the techniques is needed. PMID:24894571

  20. Detoxification of Implant Surfaces Affected by Peri-Implant Disease: An Overview of Non-surgical Methods.

    PubMed

    Valderrama, Pilar; Blansett, Jonathan A; Gonzalez, Mayra G; Cantu, Myrna G; Wilson, Thomas G

    2014-01-01

    The aim of this review is to summarize the findings of studies that have evaluated non-surgical approaches for detoxification of implant body surfaces in vitro and in vivo, and to evaluate clinical trials on the use of these methodologies for treating peri-implant disease. A literature search was conducted using MEDLINE (Pubmed) from 1966 to 2013. In vitro and in vivo studies as well as clinical trials on non-surgical therapy were evaluated. The outcome variables were the ability of the therapeutic method to eliminate the biofilm and endotoxins from the implant surface, the changes in clinical parameters including probing depth, clinical attachment levels, bleeding on probing; radiographic bone fill and histological re-osseointegration. From 134 articles found 35 were analyzed. The findings, advantages and disadvantages of using lasers as well as mechanical and chemical methods are discussed. Most of the in vivo and human studies used combination therapies which makes determining the efficacy of one specific method difficult. Most human studies are case series with short term longitudinal analysis without survival or failure reports. Complete elimination of the biofilms is difficult to achieve using these approaches. All therapies induce changes of the chemical and physical properties of the implant surface. Re-osseointegration may be difficult to achieve if not impossible without surgical access to ensure thorough debridement of the defect and detoxification of the implant surface. Combination protocols for non-surgical treatment of peri-implantitis in humans have shown some positive clinical results but long-term evaluation to evaluate the validity and reliability of the techniques is needed.

  1. A histological and histomorphometrical evaluation of retrieved human implants with a wettable, highly hydrophilic, hierarchically microstructured surface: a retrospective analysis of 14 implants.

    PubMed

    Iezzi, Giovanna; Degidi, Marco; Piattelli, Adriano; Shibli, Jamil A; Perrotti, Vittoria

    2013-04-01

    Analysis of human-retrieved implants provides a unique opportunity to evaluate osseointegration processes. There is evidence that faster bone apposition is present at textured surfaces, with a very high success percentage. Aim of the present retrospective analysis was an evaluation of 14 human retrieved from humans implants with a wettable, highly hydrophilic, microstructured surface. The archives of the Implant Retrieval Center of the Dental School, University of Chieti-Pescara, Italy, were searched, and a total of 14 implants FRIADENT plus surface (Dentsply Implants Manufacturing GmbH, Mannheim, Germany) retrieved after a loading period comprised between 4 and 8 weeks were found. Around all implants, newly formed bone was found in direct contact with the implant surface, with no connective fibrous tissue found at the interface. In all implants, no epithelial downgrowth was present. A very high bone-to-implant contact percentage was found. The efficacy of dental implants is related to biological and biomechanical stability and to the integration between the bone and the implant. This integration plays the key role in the fixation and anchoring of the implants.

  2. A novel approach for enhanced nanoparticle-sized bone substitute adhesion to chemically treated peri-implantitis-affected implant surfaces: an in vitro proof-of-principle study.

    PubMed

    Gamal, Ahmed Y; Abdel-Ghaffar, Khaled A; Iacono, Vincent J

    2013-02-01

    The objective of this study is to evaluate micro and nano-hydroxyapatite (NHA) blended clot adhesion to citric acid-conditioned peri-implantitis-affected surfaces. Forty hopeless implants with peri-implantitis designated for removal were included in this study. Implants were divided into eight groups of five each: group 1 (G1) test areas were coated with hydroxyapatite of a microparticle size (MHA); group 2 (G2) test areas were coated with NHA; group 3 (G3) implants were coated with MHA after surface conditioning using citric acid; group 4 (G4) samples were treated in the same manner as in G3 except for the use of NHA; group 5 (G5) samples were coated without surface treatment with MHA mixed with whole human blood; group 6 (G6) implant samples were treated in the same manner as in G5 except for the use of NHA; group 7 (G7) implant samples were treated in the same way as in G5 plus surface conditioning using citric acid; and group 8 (G8) samples were treated in the same manner as in G7 except for the use of NHA. All implants in all groups were agitated for 3 minutes in phosphate-buffered saline. All samples were prepared for scanning electron microscopy evaluation. G1 and G2 non-etched implants coated with MHA or NHA sizes were devoid of any bone particle adhesion to the peri-implantitis-affected surfaces. Contrary to the lack of microparticle adhesion to the root surface that was seen in G3, G4 acid-treated and NHA-coated samples revealed nearly complete coverage of the peri-implantitis-affected parts by the graft material. G5 non-etched, clot-blended MHA showed some areas of clot-blended graft adhesion covering 6.7% of the examined surfaces. G6 non-etched, clot-blended NHA showed NHA retention within the fibrin strands in areas where the implant surface pores were exposed (24.3%). G7 acid-treated and clot-blended MHA-treated implant surfaces showed partial coverage of the implant surface with detached fibrin clot-blended graft material (31.4%). G8 acid-treated and

  3. Nanoscale patterns produced by self-sputtering of solid surfaces: The effect of ion implantation

    SciTech Connect

    Bradley, R. Mark; Hofsäss, Hans

    2016-08-21

    A theory of the effect that ion implantation has on the patterns produced by ion bombardment of solid surfaces is introduced. For simplicity, the case of self-sputtering of an elemental material is studied. We find that implantation of self-ions has a destabilizing effect along the projected beam direction for angles of incidence θ that exceed a critical value. In the transverse direction, ion implantation has a stabilizing influence for all θ.

  4. Nuclear microprobe analysis of solar proton implantation profiles in lunar rock surfaces

    NASA Technical Reports Server (NTRS)

    Stauber, M. C.; Padawer, G. M.; D'Agostino, M. D.; Kamykowski, E.; Brandt, W.; Young, D. A.

    1973-01-01

    Discussion of the results of hydrogen (proton) depth profile concentration analyses conducted on selected Apollo 16 rocks. A modeling of solar particle implantation profiles in lunar rocks is shown to trace the evolvement of these profiles under the combined influence of diffusion of atomic particles implanted in the rock, and rock surface erosion. It is also demonstrated that such diffusion may have a significant effect on the shape of the implantation profiles in certain rock materials.

  5. Tantalum implanted entangled porous titanium promotes surface osseointegration and bone ingrowth

    PubMed Central

    Wang, Qi; Qiao, Yuqin; Cheng, Mengqi; Jiang, Guofeng; He, Guo; Chen, Yunsu; Zhang, Xianlong; Liu, Xuanyong

    2016-01-01

    Porous Ti is considered to be an ideal graft material in orthopaedic and dental surgeries due to its similar spatial structures and mechanical properties to cancellous bone. In this work, to overcome the bioinertia of Ti, Ta-implanted entangled porous titanium (EPT) was constructed by plasma immersion ion implantation & deposition (PIII&D) method. Ca-implanted and unimplanted EPTs were investigated as control groups. Although no difference was found in surface topography and mechanical performances, both Ca- and Ta-implanted groups had better effects in promoting MG-63 cell viability, proliferation, differentiation, and mineralization than those of unimplanted group. The expression of osteogenic-related markers examined by qRT-PCR and western blotting was upregulated in Ca- and Ta-implanted groups. Moreover, Ta-implanted EPT group could reach a higher level of these effects than that of Ca-implanted group. Enhanced osseointegration of both Ca- and Ta-implanted EPT implants was demonstrated through in vivo experiments, including micro-CT evaluation, push-out test, sequential fluorescent labeling and histological observation. However, the Ta-implanted group possessed more stable and continuous osteogenic activity. Our results suggest that Ta-implanted EPT can be developed as one of the highly efficient graft material for bone reconstruction situations. PMID:27185196

  6. Tantalum implanted entangled porous titanium promotes surface osseointegration and bone ingrowth

    NASA Astrophysics Data System (ADS)

    Wang, Qi; Qiao, Yuqin; Cheng, Mengqi; Jiang, Guofeng; He, Guo; Chen, Yunsu; Zhang, Xianlong; Liu, Xuanyong

    2016-05-01

    Porous Ti is considered to be an ideal graft material in orthopaedic and dental surgeries due to its similar spatial structures and mechanical properties to cancellous bone. In this work, to overcome the bioinertia of Ti, Ta-implanted entangled porous titanium (EPT) was constructed by plasma immersion ion implantation & deposition (PIII&D) method. Ca-implanted and unimplanted EPTs were investigated as control groups. Although no difference was found in surface topography and mechanical performances, both Ca- and Ta-implanted groups had better effects in promoting MG-63 cell viability, proliferation, differentiation, and mineralization than those of unimplanted group. The expression of osteogenic-related markers examined by qRT-PCR and western blotting was upregulated in Ca- and Ta-implanted groups. Moreover, Ta-implanted EPT group could reach a higher level of these effects than that of Ca-implanted group. Enhanced osseointegration of both Ca- and Ta-implanted EPT implants was demonstrated through in vivo experiments, including micro-CT evaluation, push-out test, sequential fluorescent labeling and histological observation. However, the Ta-implanted group possessed more stable and continuous osteogenic activity. Our results suggest that Ta-implanted EPT can be developed as one of the highly efficient graft material for bone reconstruction situations.

  7. Tantalum implanted entangled porous titanium promotes surface osseointegration and bone ingrowth.

    PubMed

    Wang, Qi; Qiao, Yuqin; Cheng, Mengqi; Jiang, Guofeng; He, Guo; Chen, Yunsu; Zhang, Xianlong; Liu, Xuanyong

    2016-05-17

    Porous Ti is considered to be an ideal graft material in orthopaedic and dental surgeries due to its similar spatial structures and mechanical properties to cancellous bone. In this work, to overcome the bioinertia of Ti, Ta-implanted entangled porous titanium (EPT) was constructed by plasma immersion ion implantation &deposition (PIII&D) method. Ca-implanted and unimplanted EPTs were investigated as control groups. Although no difference was found in surface topography and mechanical performances, both Ca- and Ta-implanted groups had better effects in promoting MG-63 cell viability, proliferation, differentiation, and mineralization than those of unimplanted group. The expression of osteogenic-related markers examined by qRT-PCR and western blotting was upregulated in Ca- and Ta-implanted groups. Moreover, Ta-implanted EPT group could reach a higher level of these effects than that of Ca-implanted group. Enhanced osseointegration of both Ca- and Ta-implanted EPT implants was demonstrated through in vivo experiments, including micro-CT evaluation, push-out test, sequential fluorescent labeling and histological observation. However, the Ta-implanted group possessed more stable and continuous osteogenic activity. Our results suggest that Ta-implanted EPT can be developed as one of the highly efficient graft material for bone reconstruction situations.

  8. Characterization of Ion Implanted and Laser Processed Wear Surfaces.

    DTIC Science & Technology

    1986-04-22

    Cavitation erosion tests were performed on nonimplanted and ion implanted samples of a Co’based hardface alloy (Stoody 3). Erosion of the test samples was...implanted samples of a Co-based hardface alloy (Stoody 3). Erosion of the test samples was found to initiate by debonding at the carbide-matrix interfaces

  9. A review of the application of anodization for the fabrication of nanotubes on metal implant surfaces.

    PubMed

    Minagar, Sepideh; Berndt, Christopher C; Wang, James; Ivanova, Elena; Wen, Cuie

    2012-08-01

    Metal implants are the best choice for the long-term replacement of hard tissue, such as hip and knee joints, because of their excellent mechanical properties. Titanium and its alloys, due to their self-organized oxide layer, which protects the surface from corrosion and prevents ion release, are widely accepted as biocompatible metal implants. Surface modification is essential for the promotion of the osseointegration of these biomaterials. Nanotubes fabricated on the surface of metal implants by anodization are receiving ever-increasing attention for surface modification. This paper provides an overview of the employment of anodization for nanotubes fabricated on the surface of titanium, titanium alloys and titanium alloying metals such as niobium, tantalum and zirconium metal implants. This work explains anodic oxidation and the manner by which nanotubes form on the surface of the metals. It then assesses this topical research to indicate how changes in anodizing conditions influence nanotube characteristics such as tube diameters and nanotube-layer thickness.

  10. Histological Evaluation of Nano-Micro Titanium Implant Surface Treatment in Beagle Humerus.

    PubMed

    Yun, Kwidug; Kang, Seongsoo; Oh, Gyejeong; Lim, Hyunpil; Lee, Kwangmin; Yang, Hongso; Vang, Mongsook; Park, Sangwon

    2016-02-01

    The objective of this study was to investigate the effects of nano-micro titanium implant surface using histology in beagle dogs. A total of 48 screw-shaped implants (Megagen, Daegu, Korea) which dimensions were 4 mm in diameter and 8.5 mm in length, were used. The implants were classified into 4 groups (n = 12): machined surface (M group), RBM (Resorbable Blasting Media) surface (R group), nano surface which is nanotube formation on the machined surface (MA group) and nano-micro surface which is nanotube formation on the RBM surface (RA group). Anodic oxidation was performed at a constant voltage of 20 V for 10 min using a DC power supply (Fine Power F-3005; SG EMD, Anyang, Korea). The bone blocks were investigated using histology. There was no inflammation around implants, and new bone formation was shown along with the nano-micro titanium implant surfaces. The amount of bone formation was increased depending on time comparing 4 weeks and 12 weeks. At 12 weeks, lamellar bone was more formed along with the nano-micro titanium implant surfaces than 4 weeks. It indicated that nano-micro surface showed good result in terms of osseointegration.

  11. Solar Wind Implantation into Lunar Regolith: Hydrogen Retention in a Surface with Defects

    NASA Astrophysics Data System (ADS)

    Farrell, W. M.; Hurley, D.; Zimmerman, M. I.

    2014-12-01

    Solar wind protons are implanted directly into the top 100 nanometers of the lunar near-surface region, but can either quickly diffuse out of the surface or be retained, depending upon surface temperature and the activation energy, U, associated with the implantation site. In this work, we explore the distribution of activation energies upon implantation and the associated hydrogen-retention times; this for comparison with recent observation of OH on the lunar surface. We apply a Monte Carlo approach: for simulated solar wind protons at a given local time, we assume a distribution of U values with a central peak, Uc and width, Uw, and derive the fraction retained for long periods in the near-surface. We find that surfaces characterized by a distribution with predominantly large values of U (> 1 eV) like that expected at defect sites will retain implanted Hs (to likely form OH). Surfaces with the distribution predominantly at small values of U (< 0.2 eV) will quickly diffuse away implanted Hs. However, surfaces with a large portion of implantation activation energies between 0.3 eV < U < 0.9 eV will tend to be H-retentive in cool conditions but transform into H-emissive surfaces when warmed (as when the surface rotates into local noon). These mid-range activation energies give rise to a diurnal effect with diffusive loss of H at noontime.

  12. Cracks and blisters formed close to a silicon wafer surface by He-H co-implantation at low energy

    SciTech Connect

    Cherkashin, N. Darras, F.-X.; Claverie, A.; Daghbouj, N.; Fnaiech, M.

    2015-12-28

    We have studied the effect of reducing the implantation energy towards low keV values on the areal density of He and H atoms stored within populations of blister cavities formed by co-implantation of the same fluence of He then H ions into Si(001) wafers and annealing. Using a variety of experimental techniques, we have measured blister heights and depth from the surface, diameter, areal density of the cracks from which they originate as functions of implantation energy and fluence. We show that there is a direct correlation between the diameters of the cracks and the heights of the associated blisters. This correlation only depends on the implantation energy, i.e., only on the depth at which the cracks are located. Using finite element method modeling, we infer the pressure inside the blister cavities from the elastic deformations they generate, i.e., from the height of the blisters. From this, we demonstrate that the gas pressure within a blister only depends on the diameter of the associated crack and not on its depth position and derive an analytical expression relating these parameters. Relating the pressure inside a blister to the respective concentrations of gas molecules it contains, we deduce the areal densities of He and H atoms contained within the populations of blisters. After low-energy implantations (8 keV He{sup +}, 3 keV H{sup +}), all the implanted He and H atoms contribute to the formation of the blisters. There is no measurable exo-diffusion of any of the implanted gases, in contrast to what was assumed at the state of the art to explain the failure of the Smart-Cut technology when using very low energy ion implantation for the fabrication of ultra-thin layers. Alternative explanations must be investigated.

  13. Cracks and blisters formed close to a silicon wafer surface by He-H co-implantation at low energy

    NASA Astrophysics Data System (ADS)

    Cherkashin, N.; Daghbouj, N.; Darras, F.-X.; Fnaiech, M.; Claverie, A.

    2015-12-01

    We have studied the effect of reducing the implantation energy towards low keV values on the areal density of He and H atoms stored within populations of blister cavities formed by co-implantation of the same fluence of He then H ions into Si(001) wafers and annealing. Using a variety of experimental techniques, we have measured blister heights and depth from the surface, diameter, areal density of the cracks from which they originate as functions of implantation energy and fluence. We show that there is a direct correlation between the diameters of the cracks and the heights of the associated blisters. This correlation only depends on the implantation energy, i.e., only on the depth at which the cracks are located. Using finite element method modeling, we infer the pressure inside the blister cavities from the elastic deformations they generate, i.e., from the height of the blisters. From this, we demonstrate that the gas pressure within a blister only depends on the diameter of the associated crack and not on its depth position and derive an analytical expression relating these parameters. Relating the pressure inside a blister to the respective concentrations of gas molecules it contains, we deduce the areal densities of He and H atoms contained within the populations of blisters. After low-energy implantations (8 keV He+, 3 keV H+), all the implanted He and H atoms contribute to the formation of the blisters. There is no measurable exo-diffusion of any of the implanted gases, in contrast to what was assumed at the state of the art to explain the failure of the Smart-Cut technology when using very low energy ion implantation for the fabrication of ultra-thin layers. Alternative explanations must be investigated.

  14. Significance of osteogenic surface coatings on implants to enhance osseointegration under osteoporotic-like conditions.

    PubMed

    Javed, Fawad; Vohra, Fahim; Zafar, Sohail; Almas, Khalid

    2014-12-01

    The aim was to assess the significance of osteogenic surface coatings on implants to enhance osseointegration under osteoporotic-like (OP-like) conditions. To address the focused question "Do osteogenic surface coatings on implants enhance osseointegration under OP-like conditions?" PubMed/MEDLINE and Google-Scholar databases were searched from 1995 up to and including February 2014 using various keywords. Unpublished data, letters to the editor, review articles, and articles published in languages other than English were excluded. Of the 28 studies identified, 11 experimental studies were included. These studies were performed on bilaterally ovariectomized animals. In all studies, implant surface roughness was increased by various osteogenetic surface coatings including alumina, hydroxyapatite, calcium phosphate, and zoledronic acid. Nine studies reported that compared with non-coated surfaces, osteogenic coatings on implant surfaces increases bone volume and bone-to-implant contact (BIC) under OP-like conditions. In 2 studies, there was no difference in BIC around hydroxyapatite-coated implants placed in animals with and without OP-like conditions. Osteogenic coatings on implant surfaces enhanced osseointegration in animals with OP-like conditions. However, additional clinical studies are warranted to assess the role of osteogenic coatings in increasing osseointegration in patients with osteoporosis.

  15. Histologic evaluation of early human bone response to different implant surfaces.

    PubMed

    Grassi, Sauro; Piattelli, Adriano; de Figueiredo, Luciene Cristina; Feres, Magda; de Melo, Leandro; Iezzi, Giovanna; Alba, Rodolfo Candia; Shibli, Jamil Awad

    2006-10-01

    Studies have demonstrated that roughened dental implant surfaces show firmer bone fixation and an increased percentage of bone-to-implant contact (BIC%) compared to commercially pure titanium-surface (machined) implants. Therefore, the purpose of this study was to evaluate the influence of implant-surface topography on human bone tissue after 2 months of unloaded healing. Fourteen subjects with a mean age of 46.87 +/- 9.45 years received two microimplants each (2.5 mm in diameter and 6 mm in length), one test (sandblasted acid-etched surface) and one control (machined surface), either in the mandible or in the maxilla. After a healing period of 2 months, the microimplants and surrounding tissues were removed with a trephine bur and prepared for histologic analysis. All microimplants, except for one of the controls, were clinically stable after the healing period. Histometric evaluation indicated that the mean BIC% was 23.08% +/- 11.95% and 42.83% +/- 9.80% for machined and rough microimplant surfaces, respectively (P = 0.0005). The bone area within the threads was also higher for sandblasted-surface implants (P = 0.0005). The mean percentage of bone density did not differ between the two groups (P = 0.578). Data from the present histological study suggest that the sandblasted acid-etched implant provides a better human bone tissue response than machined implants under unloaded conditions after a healing period of 2 months.

  16. Tongue implant for assistive technologies: Test of migration, tissue reactivity and impact on tongue function.

    PubMed

    Mimche, Sylive; Ahn, Dukju; Kiani, Mehdi; Elahi, Hassan; Murray, Kyle; Easley, Kirk; Sokoloff, Alan; Ghovanloo, Maysam

    2016-11-01

    The Tongue Drive System (TDS) is a new wearable assistive technology (AT), developed to translate voluntary tongue movements to user-defined computer commands by tracking the position of a titanium-encased magnetic tracer (Ti-Mag) implanted into the tongue. TDS application, however, is constrained by limited information on biological consequence and safety of device implantation into the tongue body. Here we implant a stainless-steel pellet in the rat tongue and assay pellet migration, tongue lick function, and tongue histology to test the safety and biocompatibility of unanchored tongue implants. Water consumption, weight and lick behavior were measured before and for >24days after implantation of a stainless-steel spherical pellet (0.5mm) into the anterior tongue body of twelve adult male rats. X-rays were obtained weekly to assess pellet migration. Pellet location and tissue reaction to implantation were determined by post-mortem dissection and histology of the anterior tongue. By dissection pellets were distributed across the transverse plane of the tongue. Measures of water consumption, weight, and lick behavior were unchanged by implantation except for a decrease in consumption immediately post-implantation in some animals. By X-ray, there was no migration of the implant, a finding supported by pellet encapsulation demonstrated histologically. Measures of lick behavior were minimally impacted by implantation. A smooth spherical stainless-steel implant in the anterior tongue of the rat does not migrate, is encapsulated and does not substantially impact lick behavior. These findings support the implantation of small tracers in the anterior tongue in humans for operating wearable assistive technologies. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Surface stiffening and enhanced photoluminescence of ion implanted cellulose - polyvinyl alcohol - silica composite.

    PubMed

    Shanthini, G M; Sakthivel, N; Menon, Ranjini; Nabhiraj, P Y; Gómez-Tejedor, J A; Meseguer-Dueñas, J M; Gómez Ribelles, J L; Krishna, J B M; Kalkura, S Narayana

    2016-11-20

    Novel Cellulose (Cel) reinforced polyvinyl alcohol (PVA)-Silica (Si) composite which has good stability and in vitro degradation was prepared by lyophilization technique and implanted using N(3+) ions of energy 24keV in the fluences of 1×10(15), 5×10(15) and 1×10(16)ions/cm(2). SEM analysis revealed the formation of microstructures, and improved the surface roughness on ion implantation. In addition to these structural changes, the implantation significantly modified the luminescent, thermal and mechanical properties of the samples. The elastic modulus of the implanted samples has increased by about 50 times compared to the pristine which confirms that the stiffness of the sample surface has increased remarkably on ion implantation. The photoluminescence of the native cellulose has improved greatly due to defect site, dangling bonds and hydrogen passivation. Electric conductivity of the ion implanted samples was improved by about 25%. Hence, low energy ion implantation tunes the mechanical property, surface roughness and further induces the formation of nano structures. MG63 cells seeded onto the scaffolds reveals that with the increase in implantation fluence, the cell attachment, viability and proliferation have improved greatly compared to pristine. The enhancement of cell growth of about 59% was observed in the implanted samples compared to pristine. These properties will enable the scaffolds to be ideal for bone tissue engineering and imaging applications.

  18. In vitro cytotoxicity and surface topography evaluation of additive manufacturing titanium implant materials.

    PubMed

    Tuomi, Jukka T; Björkstrand, Roy V; Pernu, Mikael L; Salmi, Mika V J; Huotilainen, Eero I; Wolff, Jan E H; Vallittu, Pekka K; Mäkitie, Antti A

    2017-03-01

    Custom-designed patient-specific implants and reconstruction plates are to date commonly manufactured using two different additive manufacturing (AM) technologies: direct metal laser sintering (DMLS) and electron beam melting (EBM). The purpose of this investigation was to characterize the surface structure and to assess the cytotoxicity of titanium alloys processed using DMLS and EBM technologies as the existing information on these issues is scarce. "Processed" and "polished" DMLS and EBM disks were assessed. Microscopic examination revealed titanium alloy particles and surface flaws on the processed materials. These surface flaws were subsequently removed by polishing. Surface roughness of EBM processed titanium was higher than that of DMLS processed. The cytotoxicity results of the DMLS and EBM discs were compared with a "gold standard" commercially available titanium mandible reconstruction plate. The mean cell viability for all discs was 82.6% (range, 77.4 to 89.7) and 83.3% for the control reconstruction plate. The DMLS and EBM manufactured titanium plates were non-cytotoxic both in "processed" and in "polished" forms.

  19. A new method for inner surface modification by plasma source ion implantation (PSII)

    NASA Astrophysics Data System (ADS)

    Liu, Bin; Liu, Chizi; Cheng, Dajung; Zhang, Guling; He, Rui; Yang, Si-Ze

    2001-12-01

    A new method for inner surface modification, named grid-enhanced inner surface modification by plasma source ion implantation (PSII), was proposed and demonstrated in this paper. By introducing an RF plasma core, which is produced between a central cathode and a coaxial grid electrode, and sputtering the cathode, uniform ion implantation and film deposition on the inner surface of a tubular sample can be realized based upon the PSII technique.

  20. Surface modification of biomaterials using plasma immersion ion implantation and deposition

    PubMed Central

    Lu, Tao; Qiao, Yuqin; Liu, Xuanyong

    2012-01-01

    Although remarkable progress has been made on biomaterial research, the ideal biomaterial that satisfies all the technical requirements and biological functions is not available up to now. Surface modification seems to be a more economic and efficient way to adjust existing conventional biomaterials to meet the current and ever-evolving clinical needs. From an industrial perspective, plasma immersion ion implantation and deposition (PIII&D) is an attractive method for biomaterials owing to its capability of treating objects with irregular shapes, as well as the control of coating composition. It is well acknowledged that the physico-chemical characteristics of biomaterials are the decisive factors greatly affecting the biological responses of biomaterials including bioactivity, haemocompatibility and antibacterial activity. Here, we mainly review the recent advances in surface modification of biomaterials via PIII&D technology, especially titanium alloys and polymers used for orthopaedic, dental and cardiovascular implants. Moreover, the variations of biological performances depending on the physico-chemical properties of modified biomaterials will be discussed. PMID:23741609

  1. Surface observation of thin hydroxyapatite-coated implants at 80 months after insertion.

    PubMed

    Sugiyama, Tetsuya; Miake, Yasuo; Yajima, Yasutomo; Yamamoto, Kohji; Sakurai, Kaoru

    2011-04-01

    We observed surfaces and cross sections of thin hydroxyapatite (HA)-coated implants produced by the thermal decomposition method in a patient attending our clinic who underwent implant removal at 80 months due to fracture of the implants. On the implant surfaces of the removed sample, most of the HA had dissolved, and extensive osseointegration was observed where Ti had closely bonded to bone. This indicated that the HA coated on the implant surfaces had disappeared and osseointegration had been established where Ti directly bonded to the bone. In addition, calcium titanate (CaTiO(3)) and HA layers formed by the thermal decomposition method showed no desorption. The results clearly indicate the positive clinical potential of thin HA-coating by the thermal decomposition method.

  2. Pectin nanocoating of titanium implant surfaces - an experimental study in rabbits.

    PubMed

    Gurzawska, Katarzyna; Dirscherl, Kai; Jørgensen, Bodil; Berglundh, Tord; Jørgensen, Niklas Rye; Gotfredsen, Klaus

    2017-03-01

    A major determinant of successful osseointegration of endosseous implants is the surface of the implant, which influences the cellular response of the surrounding tissues. A new strategy to improve osseointegration and bone healing is biochemical stimulation by surface nanocoatings that may increase adhesion of bone proteins, and bone cells at the implant surface. Nanocoating with pectins, plant cell wall-derived polysaccharides, is frequently done using rhamnogalacturonan-I (RG-I). The aim of the study was to evaluate the effect of nanocoating titanium implants with plant cell wall-derived rhamnogalacturonan-I, on bone healing and osseointegration. Machined titanium implants were coated with three modifications of rhamnogalacturonan-I (RG-I). Chemical and physical surface properties were examined before insertion of nanocoated implants (n = 96) into the left and right tibia of rabbits. Machined titanium implants without RG-I nanocoating were used as controls (n = 32). Total number of 128 implants was placed in tibias of 16 rabbits. Fluorochrome bone labels, calcein green and alizarin red S were given intravenously after 9 and 12 days, respectively. The bone response to the nanocoated implants was analyzed qualitatively and quantitatively after 2, 4, 6, and 8 weeks of healing using light microscopy and histomorphometric methods. The RG-I coating influenced the surface chemical composition; wettability and roughness, making the surface more hydrophilic without any major effect on surface micro roughness compared to control implant surfaces. The different modifications of pectin RG-I did not significantly enhance bone healing and osseointegration analyzed after 2, 4, 6, and 8 weeks of healing compared to control implants. Although the qualitative analyses of the fluorochromes indicated a higher activity of bone formation in the mineralization front at the early stage, after 9 and 12 days at the RG-I nanocoated implants compared to the control implants

  3. Surface characteristics and cell adhesion: a comparative study of four commercial dental implants.

    PubMed

    Liu, Ruohong; Lei, Tianhua; Dusevich, Vladimir; Yao, Xiamei; Liu, Ying; Walker, Mary P; Wang, Yong; Ye, Ling

    2013-12-01

    The aims of this study were to compare surface properties of four commercial dental implants and to compare those implant systems' cell adhesion, which may be affected by the surface properties, and to provide scientific information on the selection of implants for clinicians. The surface properties of four commonly used dental implants (3i Nanotite™, Astra OsseoSpeed™, Nobel Biocare TiUnite®, and Straumann SLActive®) were studied using MicroSpy profiler, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy, and Raman microspectroscopy. Primary mouse alveolar bone cells were cultured on the surface of implants from the four companies. After 48-hour culture, SEM in combination with a quantitative analysis of SEM images was used to examine the cell adhesion. Cell adhesion rates (ratios of cell surface to implant surface) among different systems were compared. Distinct differences were found among these implants. Comparisons of roughness among three locations: flank, top, and valley within the same implant system, or in the same location among different implants were made. Generally Astra and Straumann systems showed the roughest surface, whereas 3i showed the smoothest surface. Multiple cracks were found on the surface of the Nobel Biocare system, which also had a dramatically lower level of titanium. In addition, rutile phase of titanium oxide was found in 3i, Astra, and Straumann systems, and anatase phase of titanium oxide was only detected in the Nobel Biocare system. After 48-hour culture, Astra and Straumann systems displayed the highest cell adhesion at the areas of flank, top, and valley of the implant surface. Primary cells also reached confluence on the valley, but significantly less in the 3i system. Nobel Biocare showed the least cell adhesion on the flank and valley. Implant systems have distinct differences in surface properties, leading to different cell adhesion results. Further in vivo study is needed to study the impact of

  4. Histomorphometric and biomechanical analyses of osseointegration of four different orthodontic mini implant surfaces

    NASA Astrophysics Data System (ADS)

    Yadav, Sumit

    Objective: To evaluate the osseointegration potential of four different surfaces of mini-implants. We hypothesized that mini-implants surface roughness alters the intrinsic biomechanical properties of the bone integrated to titanium. Materials and Methods: Mini implants and circular discs were made from alloy Ti6Al4V grade 5. On the basis of surface treatment study was divided into 4 groups: Group 1: Machined: no surface treatment, Group 2: Acid etched: with hydrochloric acid, Group 3: Grit Blasted with alumina and Group 4: Grit blasted +Acid etched. Surface roughness parameters (mean surface roughness: Ra and Quadratic Average roughness: Rq) of the four discs from each group were measured by the optical profilometer. Contact angle measurement of 3 discs from each group was done with a Goniometer. Contact angle of liquids with different hydrophobicity and hydrophilicity were measured. 128 mini implants, differing in surface treatment, were placed into the tibias and femurs of 8 adult male New Zealand white rabbits. Biomechanical properties (Removal torque and hardness) measurements and histomorphometric observations were measured. Results: Ra and Rq of groups were: Machined (1.17+/-0.11, 2.59+/-0.09) Acid etched (1.82+/-0.04, 3.17+/-0.13), Grit blasted (4.83+/-0.23, 7.04+/-0.08), Grit blasted + Acid etched (3.64+/-0.03, 4.95+/-0.04) respectively. Group 4 had significantly (p=0.000) lower Ra and Rq than Group 3. The interaction between the groups and liquid was significant. Group 4 had significantly lower contact angle measurements (40.4°, 26.9°), both for blood and NaCl when compared to other three groups (p≤0.01). Group 4 had significantly higher torque than Group 3 (Tibia: 13.67>9.07N-cm; Femur: 18.21>14.12N-cm), Group 4 (Tibia: 13.67>9.78N-cm; Femur: 18.21>12.87N-cm), and machined (Tibia: 13.67>4.08N-cm; Femur: 18.21>6.49N-cm). SEM analysis reveals significantly more bone implant gap in machined implant surfaces than treated implant surfaces. Bone to implant

  5. Characteristics of contact and distance osteogenesis around modified implant surfaces in rabbit tibiae

    PubMed Central

    2017-01-01

    Purpose Contact and distance osteogenesis occur around all endosseous dental implants. However, the mechanisms underlying these processes have not been fully elucidated. We hypothesized that these processes occur independently of each other. To test this, we used titanium (Ti) tubes to physically separate contact and distance osteogenesis, thus allowing contact osteogenesis to be measured in the absence of possible triggers from distance osteogenesis. Methods Sandblasted and acid-etched (SLA) and modified SLA (modSLA) implants were used. Both types had been sandblasted with large grit and then etched with acid. The modSLA implants then underwent additional treatment to increase hydrophilicity. The implants were implanted into rabbit tibiae, and half were implanted within Ti tubes. The bone-to-implant contact (BIC) ratio was calculated for each implant. Immunohistochemical analyses of bone morphogenetic protein (BMP)-2 expression and new bone formation (Masson trichrome stain) were performed. Results The implants outside of Ti tubes were associated with good bone formation along the implant surface. Implantation within a Ti tube significantly reduced the BIC ratio (P<0.001). Compared with the modSLA implants, the SLA implants were associated with significantly higher BIC ratios, regardless of the presence or absence of Ti tubes (P=0.043). In the absence of Ti tubes, the bone adjacent to the implant had areas of new bone formation that expressed BMP-2 at high levels. Conclusions This study disproved the null hypothesis and suggested that contact osteogenesis is initiated by signals from the old bone that undergoes distance osteogenesis after drilling. This signal may be BMP-2. PMID:28680714

  6. Dosimetry of I-125 seeds implanted on the surface of a cavity

    SciTech Connect

    Prasad, S.C.; Bassano, D.A.; Fear, P.I.; King, G.A. )

    1990-12-01

    Dosimetry of a new implant technique to treat brain tumors is presented. High grade gliomas or astrocytomas are surgically removed, and radioactive I-125 seeds are implanted on the surface of the cavity. A computational model is presented to determine the number of seeds and the activity of the seeds for a given dose and cavity size.

  7. Implant Surface Temperature Changes during Er:YAG Laser Irradiation with Different Cooling Systems.

    PubMed

    Monzavi, Abbas; Shahabi, Sima; Fekrazad, Reza; Behruzi, Roohollah; Chiniforush, Nasim

    2014-03-01

    Peri-implantitis is one of the most common reasons for implant failure. Decontamination of infected implant surfaces can be achieved effectively by laser irradiation; although the associated thermal rise may cause irreversible bone damage and lead to implant loss. Temperature increments of over 10ºC during laser application may suffice for irreversible bone damage. The purpose of this study was to evaluate the temperature increment of implant surface during Er:YAG laser irradiation with different cooling systems. Three implants were placed in a resected block of sheep mandible and irradiated with Er:YAG laser with 3 different cooling systems namely water and air spray, air spray alone and no water or air spray. Temperature changes of the implant surface were monitored during laser irradiation with a K-type thermocouple at the apical area of the fixture. In all 3 groups, the maximum temperature rise was lower than 10°C. Temperature changes were significantly different with different cooling systems used (P<0.001). Based on the results, no thermal damage was observed during implant surface decontamination by Er:YAG laser with and without refrigeration. Thus, Er:YAG laser irradiation can be a safe method for treatment of periimplantitis.

  8. Bone response to the multilayer BMP-2 gene coated porous titanium implant surface.

    PubMed

    Jiang, Qiao-Hong; Liu, Li; Peel, Sean; Yang, Guo-Li; Zhao, Shi-Fang; He, Fu-Ming

    2013-08-01

    Evaluate hBMP-2 expression following gene delivery from plasmid multilayers formed on sandblasted titanium in vitro and bone formation around similarly prepared implant surfaces in vivo. Multilayers of cationic lipid/rhBMP-2 plasmid DNA complex (LDc) and anionic hyaluronic acid (HA) was assembled on sandblasted-dual acid etched pure titanium disks or implant surfaces using layer-by-layer (LBL) assembly. Gene delivery and hBMP-2 expression in cells exposed to the LDc multilayers was measured in vitro. To determine the effect of BMP delivery from such multilyaers in vivo, roughened implants coated with BMP-2 LDc multilayers or uncoated control implants (n = 15 for both) were implanted in the femurs of NZW rabbits. After 2, 4, 8 weeks, femurs were retrieved and prepared for histomorphometric evaluation (n = 5 rabbits per time point). MC3T3-E1 cells cultured directly on the BMP-2 LDc coated titanium disks showed EGFP and hBMP-2 expression after 48 h in culture. Increased gene delivery occurred by increasing the number of assembly layers when cells were cultured for 48 h. Cells cultured on LDc coated surfaces had significantly higher cell viability than control cells cultured on uncoated porous titanium surfaces. Histologic observation of the implants showed that after 4 weeks healing, the bone to implant contact (BIC) on the LDc coated surface was much lower than that on the control surface, but didn't reach significant. In contrast, the percentage of bone within the implant's threads was significantly higher than the control group (P = 0.047). The BMP-2 gene coated sandblasted dual acid etched titanium implants slightly accelerated early bone formation around implants. © 2011 John Wiley & Sons A/S.

  9. Development, fabrication and evaluation of a novel biomimetic human breast tissue derived breast implant surface.

    PubMed

    Barr, S; Hill, E W; Bayat, A

    2017-02-01

    Breast implant use has tripled in the last decade with over 320,000 breast implant based reconstructions and augmentations performed in the US per annum. Unfortunately a considerable number of women will experience capsular contracture, the irrepressible and disfiguring, tightening and hardening of the fibrous capsule that envelops the implant. Functionalising implant surfaces with biocompatible tissue-specific textures may improve in vivo performance. A novel biomimetic breast implant is presented here with anti-inflammatory in vitro abilities. Topographical assessment of native breast tissue facilitated the development of a statistical model of adipose tissue. 3D grayscale photolithography and ion etching were combined to successfully replicate a surface modelled upon the statistics of breast tissue. Pro-inflammatory genes ILβ1, TNFα, and IL6 were downregulated (p<0.001) and anti-inflammatory gene IL-10 were upregulated on the novel surface. Pro-inflammatory cytokines Gro-Alpha, TNFα and neutrophil chemoattractant IL8 were produced in lower quantities and anti-inflammatory IL-10 in higher quantities in culture with the novel surface (p<0.01). Immunocytochemistry and SEM demonstrated favourable fibroblast and macrophage responses to these novel surfaces. This study describes the first biomimetic breast tissue derived breast implant surface. Our findings attest to its potential translational ability to reduce the inflammatory phase of the implant driven foreign body reaction.

  10. N and Cr ion implantation of natural ruby surfaces and their characterization

    NASA Astrophysics Data System (ADS)

    Rao, K. Sudheendra; Sahoo, Rakesh K.; Dash, Tapan; Magudapathy, P.; Panigrahi, B. K.; Nayak, B. B.; Mishra, B. K.

    2016-04-01

    Energetic ions of N and Cr were used to implant the surfaces of natural rubies (low aesthetic quality). Surface colours of the specimens were found to change after ion implantation. The samples without and with ion implantation were characterized by diffuse reflectance spectra in ultra violet and visible region (DRS-UV-Vis), field emission scanning electron microscopy (FESEM), selected area electron diffraction (SAED) and nano-indentation. While the Cr-ion implantation produced deep red surface colour (pigeon eye red) in polished raw sample (without heat treatment), the N-ion implantation produced a mixed tone of dark blue, greenish blue and violet surface colour in the heat treated sample. In the case of heat treated sample at 3 × 1017 N-ions/cm2 fluence, formation of colour centres (F+, F2, F2+ and F22+) by ion implantation process is attributed to explain the development of the modified surface colours. Certain degree of surface amorphization was observed to be associated with the above N-ion implantation.

  11. Air powder abrasive treatment as an implant surface cleaning method: a literature review.

    PubMed

    Tastepe, Ceylin S; van Waas, Rien; Liu, Yuelian; Wismeijer, Daniel

    2012-01-01

    To evaluate the air powder abrasive treatment as an implant surface cleaning method for peri-implantitis based on the existing literature. A PubMed search was conducted to find articles that reported on air powder abrasive treatment as an implant surface cleaning method for peri-implantitis. The studies evaluated cleaning efficiency and surface change as a result of the method. Furthermore, cell response toward the air powder abrasive-treated discs, reosseointegration, and clinical outcome after treatment is also reported. The PubMed search resulted in 27 articles meeting the inclusion criteria. In vitro cleaning efficiency of the method is reported to be high. The method resulted in minor surface changes on titanium specimens. Although the air powder abrasive-treated specimens showed sufficient levels of cell attachment and cell viability, the cell response decreased compared with sterile discs. Considerable reosseointegration between 39% and 46% and improved clinical parameters were reported after treatment when applied in combination with surgical treatment. The results of the treatment are influenced by the powder type used, the application time, and whether powder was applied surgically or nonsurgically. The in vivo data on air powder abrasive treatment as an implant surface cleaning method is not sufficient to draw definitive conclusions. However, in vitro results allow the clinician to consider the method as a promising option for implant surface cleaning in peri-implantitis treatment.

  12. Bacterial inactivation/sterilization by argon plasma treatment on contaminated titanium implant surfaces:In vitro study

    PubMed Central

    Annunziata, Marco; Donnarumma, Giovanna; Caputo, Pina; Nastri, Livia; Guida, Luigi

    2016-01-01

    Background Surface treatment by argon plasma is widely used as the last step of the manufacturing process of titanium implant fixtures before their sterilization by gamma rays. The possibility of using such a technology in the daily clinical practice is particularly fascinating. The aim of the present study was to assess the effects of the argon plasma treatment on different titanium implant surfaces previously exposed In vitro to bacterial contamination. Material and Methods Sterile c.p. titanium implant discs with turned (T, Sa: 0.8 µm ), sandblasted/acid-etched (SAE, Sa: 1.3 µm) and titanium plasma sprayed (TPS, Sa: 3.0µm) surface were used in this study. A strain of Aggregatibacter actinomycetemcomitans ATCC3718 was grown at 37°C under anaerobic conditions for 24 h and then transferred on six discs for each of the three surface types. After 24 hours, a half of the contaminated discs (control group) were directly used to evaluate the colony forming units (CFUs). The other half of the contaminated discs (test group) were treated in an argon plasma chamber for 12 minutes at room temperature prior to be analyzed for CFU counting. All assays were performed using triplicate samples of each material in 3 different experiments. Results When the CFU counting was carried out on control discs, a total of 1.50x106±1.4x105, 1.55x106±7.07x104 and 3.15x106±2.12x105 CFU was respectively assessed for T, SAE and TPS discs, without statistically significant differences among the three surfaces. On the contrary, any trace of bacterial contamination was assessed for titanium discs treated in the argon plasma chamber prior to be analyzed, irrespectively to the implant surface tested. Conclusions Within the limit of this study, reported data suggested that the argon plasma technology could be efficiently used to decontaminate/sterilize previously infected titanium implant surfaces. Key words:Argon plasma, titanium implant surface, Aggregatibacter actinomycetemcomitans. PMID

  13. Fission Surface Power Technology Development Status

    NASA Technical Reports Server (NTRS)

    Palac, Donald T.; Mason, Lee S.; Houts, Michael G.; Harlow, Scott

    2010-01-01

    Power is a critical consideration in planning exploration of the surfaces of the Moon, Mars, and beyond. Nuclear power is an important option, especially for locations in the solar system where sunlight is limited in availability or intensity. NASA is maintaining the option for fission surface power for the Moon and Mars by developing and demonstrating technology for an affordable fission surface power system. Because affordability drove the determination of the system concept that this technology will make possible, low development and recurring costs result, while required safety standards are maintained. However, an affordable approach to fission surface power also provides the benefits of simplicity, robustness, and conservatism in design. This paper will illuminate the multiplicity of benefits to an affordable approach to fission surface power, and will describe how the foundation for these benefits is being developed and demonstrated in the Exploration Technology Development Program s Fission Surface Power Project.

  14. In vivo biocompatibility of Mg implants surface modified by nanostructured merwinite/PEO.

    PubMed

    Razavi, Mehdi; Fathi, Mohammadhossein; Savabi, Omid; Vashaee, Daryoosh; Tayebi, Lobat

    2015-05-01

    Magnesium (Mg) alloys have been suggested as biodegradable bone implant materials due to their good intrinsic biocompatibility and great mechanical properties. Although magnesium has attractive properties as an orthopedic implant material, its quick degradation and low bioactivity may lead to the loss of mechanical integrity of the implant during the bone healing process. In this paper, we endeavor to surmount the abovementioned defects using the surface coating technique. We have recently coated AZ91 magnesium implants with merwinite (Ca3MgSi2O8) through the coupling of plasma electrolytic oxidation (PEO) and electrophoretic deposition method. In this work, we are specifically focused on the in vivo examinations of the coated implants in comparison with the uncoated one. For the in vivo experiment, the rod samples, including the uncoated and merwinite/PEO coated implants, were imbedded into the greater trochanter of rabbits. The results of the in vivo animal test indicated an improvement in biodegradability including slower implant weight loss, reduction in Mg ion released from the coated implants in the blood plasma, lesser release of hydrogen bubbles and an improvement in biocompatibility including an increase in the amount of bone formation and ultimately a mild bone inflammation after the surgery according to the histological images. In summary, proper surface treatment of magnesium implants such as silicate bioactive ceramics may improve their biocompatibility under physiological conditions to making them suitable and applicable for future clinical applications.

  15. Cruciate Retaining Implant With Biomimetic Articular Surface to Reproduce Activity Dependent Kinematics of the Normal Knee.

    PubMed

    Varadarajan, Kartik Mangudi M; Zumbrunn, Thomas; Rubash, Harry E; Malchau, Henrik; Li, Guoan; Muratoglu, Orhun K

    2015-12-01

    Alterations in normal knee kinematics following total knee arthroplasty (TKA) arise in part from the non-anatomic articular geometry of contemporary implants. In this study, the kinematics of a novel posterior cruciate-retaining (CR) implant with anatomic (biomimetic) articular surface, were compared to that of contemporary CR implants during various simulated activities. Across different simulated activities the biomimetic-CR mimicked normal kinematic patterns more closely than contemporary CR implants. In particular, during deep knee bend and chair-sit, the biomimetic-CR showed medial pivot motion, while other CR implants showed abnormal motion including lateral pivot or no pivot, and paradoxical anterior sliding. Further in vivo and clinical studies are needed to determine whether such biomimetic implants can truly help to achieve a more normal feeling knee and improved patient satisfaction.

  16. Tribological properties and surface structures of ion implanted 9Cr18Mo stainless steels

    NASA Astrophysics Data System (ADS)

    Fengbin, Liu; Guohao, Fu; Yan, Cui; Qiguo, Sun; Min, Qu; Yi, Sun

    2013-07-01

    The polished quenched-and-tempered 9Cr18Mo steels were implanted with N ions and Ti ions respectively at a fluence of 2 × 1017 ions/cm2. The mechanical properties of the samples were investigated by using nanoindenter and tribometer. The results showed that the ion implantations would improve the nanohardness and tribological property, especially N ion implantation. The surface analysis of the implanted samples was carried out by using XRD, XPS and AES. It indicated that the surface exhibits graded layers after ion implantation. For N ion implantation, the surface about 20 nm thickness is mainly composed of supersaturated interstitial N solid solution, oxynitrides, CrxCy phase and metal nitrides. In the subsurface region, the metal nitrides dominate and the other phases disappear. For Ti ion implantation, the surface of about 20 nm thickness is mainly composed of titanium oxides and carbon amorphous phase, the interstitial solid solution of Ti in Fe is abundant in the subsurface region. The surface components and structures have significant contributions to the improved mechanical properties.

  17. Microarray expression in peri-implant tissue next to different titanium implant surfaces predicts clinical outcomes: a split-mouth study.

    PubMed

    Menini, M; Dellepiane, E; Baldi, D; Longobardi, M G; Pera, P; Izzotti, A

    2017-09-01

    This split-mouth study evaluated miRNA expression of tissues around implants with different surface treatments. Each patient of the sample (five men and five women) received two implants (one control and one test) into an edentulous quadrant to support fixed partial dentures. The control implants (Osseotite) had a dual acid-etched (DAE) surface in the apical portion and a machined coronal part, test implants (Full Osseotite, FOSS) were completely DAE. Machined healing abutments were placed on control implants and DAE abutments on test ones. All implants were assigned codes for blinding. Standardized periapical radiographs were taken at baseline, 2 and 6 months, and 1 year after surgery. Plaque index (PI), bleeding on probing (BOP), and probing depth (PD) were recorded at 3 and 6 weeks, and 2, 3, 6, and 12 months post-implant placement. After 3 months, a mini-invasive sample of soft tissue was collected from seven patients (four women and three men) for miRNA microarray analysis. Control implants showed greater bone resorption (BR) and lower PI: this was not statistically significant. No statistically significant differences in BOP and PD appeared. miRNA modulated by implant surfaces as well as by other clinical conditions has been identified. miRNA microarray analysis revealed that: (i) implant sites with low PI and absence of BOP had a miRNA expression profile similar to those with plaque and absence of BOP; sites with high PI and high BOP had a different profile. (ii) Implant sites with BOP presented similar profiles independently from implant surface. (iii) Implant sites with high PI and normal BR differed from others for miRNA expression profile. (iv) Implant sites with normal BR despite high BOP differed from others. This profile resembled that of FOSS implants. (v) Implant surface affected BR; groups having similar BR clusterized differently according to the implant type. DAE surfaces induced lower BR and more plaque accumulation: This did not affect the

  18. In vitro and in vivo evaluation of novel implantation technology in hydrogel contact lenses for controlled drug delivery.

    PubMed

    Maulvi, Furqan A; Lakdawala, Dhara H; Shaikh, Anjum A; Desai, Ankita R; Choksi, Harsh H; Vaidya, Rutvi J; Ranch, Ketan M; Koli, Akshay R; Vyas, Bhavin A; Shah, Dinesh O

    2016-03-28

    Glaucoma is commonly treated using eye drops, which is highly inefficient due to rapid clearance (low residence time) from ocular surface. Contact lenses are ideally suited for controlled drug delivery to cornea, but incorporation of any drug loaded particulate system (formulation) affect the optical and physical property of contact lenses. The objective of the present work was to implant timolol maleate (TM) loaded ethyl cellulose nanoparticle-laden ring in hydrogel contact lenses that could provide controlled drug delivery at therapeutic rates without compromising critical lens properties. TM-implant lenses were developed, by dispersing TM encapsulated ethyl cellulose nanoparticles in acrylate hydrogel (fabricated as ring implant) and implanted the same in hydrogel contact lenses (sandwich system). The TM-ethyl cellulose nanoparticles were prepared by double emulsion method at different ratios of TM to ethyl cellulose. The X-ray diffraction studies revealed the transformation of TM to amorphous state. In vitro release kinetic data showed sustained drug release within the therapeutic window for 168h (NP 1:3 batch) with 150μg loading. Cytotoxicity and ocular irritation study demonstrated the safety of TM-implant contact lenses. In vivo pharmacokinetic studies in rabbit tear fluid showed significant increase in mean residence time (MRT) and area under curve (AUC), with TM-implant contact lenses in comparison to eye drop therapy. In vivo pharmacodynamic data in rabbit model showed sustained reduction in intra ocular pressure for 192h. The study demonstrated the promising potential of implantation technology to treat glaucoma using contact lenses, and could serve as a platform for other ocular diseases.

  19. The Effect of Laminin-1-Doped Nanoroughened Implant Surfaces: Gene Expression and Morphological Evaluation

    PubMed Central

    Schwartz-Filho, Humberto Osvaldo; Bougas, Kostas; Coelho, Paulo G.; Xue, Ying; Hayashi, Mariko; Faeda, Rafael Silveira; Marcantonio, Rosemary Adriana Chiérici; Ono, Daisuke; Kobayashi, Fumio; Mustafa, Kamal; Wennerberg, Ann; Jimbo, Ryo

    2012-01-01

    Aim. This study aimed to observe the morphological and molecular effect of laminin-1 doping to nanostructured implant surfaces in a rabbit model. Materials and Methods. Nanostructured implants were coated with laminin-1 (test; dilution, 100 μg/mL) and inserted into the rabbit tibiae. Noncoated implants were used as controls. After 2 weeks of healing, the implants were removed and subjected to morphological analysis using scanning electron microscopy (SEM) and gene expression analysis using the real-time reverse transcriptase-polymerase chain reaction (RT-PCR). Results. SEM revealed bony tissue attachment for both control and test implants. Real-time RT-PCR analysis showed that the expression of osteoblast markers RUNX-2, osteocalcin, alkaline phosphatase, and collagen I was higher (1.62-fold, 1.53-fold, 1.97-fold, and 1.04-fold, resp.) for the implants modified by laminin-1 relative to the control. All osteoclast markers investigated in the study presented higher expression on the test implants than controls as follows: tartrate-resistant acid phosphatase (1.67-fold), calcitonin receptor (1.35-fold), and ATPase (1.25-fold). The test implants demonstrated higher expression of inflammatory markers interleukin-10 (1.53-fold) and tumour necrosis factor-α (1.61-fold) relative to controls. Conclusion. The protein-doped surface showed higher gene expression of typical genes involved in the osseointegration cascade than the control surface. PMID:23304151

  20. Positive Biomechanical Effects of Titanium Oxide for Sandblasting Implant Surface as an Alternative to Aluminium Oxide.

    PubMed

    Gehrke, Sergio Alexandre; Taschieri, Silvio; Del Fabbro, Massimo; Coelho, Paulo Guilherme

    2015-10-01

    The aim of this study was to evaluate the physico-chemical properties and the in vivo host response of a surface sandblasted with particles of titanium oxide (TiO2) followed by acid etching as an alternative to aluminium oxide. Thirty titanium disks manufactured in the same conditions as the implants and 24 conventional cylindrical implants were used. Half of the implants had a machined surface (Gcon) while in the other half; the surface was treated with particles of TiO2 followed by acid etching (Gexp). Surface characterization was assessed by scanning electron microscope (SEM), energy dispersive X-ray spectrometry (EDS), profilometry, and wettability. For the in vivo test, 12 implants of each group were implanted in the tibia of 6 rabbits, and were reverse torque tested after periods of 30 or 60 days after implantation. Following torque, SEM was utilized to assess residual bone-implant contact. The surface characterization by SEM showed a very homogeneous surface with uniform irregularities for Gexp and a small amount of residues of the blasting procedure, while Gcon presented a surface with minimal irregularities from the machining tools. Wettability test showed decreased contact angle for the Gcon relative to the Gexp. The Gexp removal torque at 30 and 60 days was 28.7%, and 33.2% higher relative to the Gcon, respectively. Blasting the surface with particles of TiO2 represents an adequate option for the surface treatment of dental implants, with minimal risk of contamination by the residual debris from the blasting procedure.

  1. The application of implant technology for cybernetic systems.

    PubMed

    Warwick, Kevin; Gasson, Mark; Hutt, Benjamin; Goodhew, Iain; Kyberd, Peter; Andrews, Brian; Teddy, Peter; Shad, Amjad

    2003-10-01

    To assess the usefulness, compatibility, and long-term operability of a microelectrode array into the median nerve of the left arm of a healthy volunteer, including perception of feedback stimulation and operation of an instrumented prosthetic hand. The study was carried out from March 14 through June 18, 2002, in England and the United States. The blindfolded subject received feedback information, obtained from force and slip sensors on the prosthetic hand, and subsequently used the implanted device to control the hand by applying an appropriate force to grip an unseen object. Operability was also demonstrated remotely via the Internet, with the subject in New York, NY, and the prosthetic hand in Reading, England. Finally, the subject was able to control an electric wheelchair, via decoded signals from the implant device, to select the direction of travel by opening and closing his hand. The implantation did not result in infection or any perceivable loss of hand sensation or motion control. The implant was finally extracted because of mechanical fatigue of the percutaneous connection. Further testing after extraction has not indicated any measurable long-term defects in the subject. This implant may allow recipients to have abilities they would otherwise not possess. The response to stimulation improved considerably during the trial, suggesting that the subject learned to process the incoming information more effectively.

  2. Plasma-based ion implantation: a valuable technology for the elaboration of innovative materials and nanostructured thin films

    NASA Astrophysics Data System (ADS)

    Vempaire, D.; Pelletier, J.; Lacoste, A.; Béchu, S.; Sirou, J.; Miraglia, S.; Fruchart, D.

    2005-05-01

    Plasma-based ion implantation (PBII), invented in 1987, can now be considered as a mature technology for thin film modification. After a brief recapitulation of the principle and physics of PBII, its advantages and disadvantages, as compared to conventional ion beam implantation, are listed and discussed. The elaboration of thin films and the modification of their functional properties by PBII have already been achieved in many fields, such as microelectronics (plasma doping/PLAD), biomaterials (surgical implants, bio- and blood-compatible materials), plastics (grafting, surface adhesion) and metallurgy (hard coatings, tribology), to name a few. The major advantages of PBII processing lie, on the one hand, in its flexibility in terms of ion implantation energy (from 0 to 100 keV) and operating conditions (plasma density, collisional or non-collisional ion sheath), and, on the other hand, in the easy transferrability of processes from the laboratory to industry. The possibility of modifying the composition and physical nature of the films, or of drastically changing their physical properties over several orders of magnitude makes this technology very attractive for the elaboration of innovative materials, including metastable materials, and the realization of micro- or nanostructures. A review of the state of the art in these domains is presented and illustrated through a few selected examples. The perspectives opened up by PBII processing, as well as its limitations, are discussed.

  3. Electric Arc and Electrochemical Surface Texturing Technologies

    NASA Technical Reports Server (NTRS)

    Banks, Bruce A.; Rutledge, Sharon K.; Snyder, Scott A.

    1997-01-01

    Surface texturing of conductive materials can readily be accomplished by means of a moving electric arc which produces a plasma from the environmental gases as well as from the vaporized substrate and arc electrode materials. As the arc is forced to move across the substrate surface, a condensate from the plasma re-deposits an extremely rough surface which is intimately mixed and attached to the substrate material. The arc textured surfaces produce greatly enhanced thermal emittance and hold potential for use as high temperature radiator surfaces in space, as well as in systems which use radiative heat dissipation such as computer assisted tomography (CAT) scan systems. Electrochemical texturing of titanium alloys can be accomplished by using sodium chloride solutions along with ultrasonic agitation to produce a random distribution of craters on the surface. The crater size and density can be controlled to produce surface craters appropriately sized for direct bone in-growth of orthopaedic implants. Electric arc texturing and electrochemical texturing techniques, surface properties and potential applications will be presented.

  4. Effect of implant surface microtopography on proliferation, neurotrophin secretion, and gene expression of Schwann cells.

    PubMed

    Yuan, Quan; Liao, Dapeng; Yang, Xingmei; Li, Xiaoyu; Wei, Na; Tan, Zhen; Gong, Ping

    2010-04-01

    The purpose of this study was to evaluate the effect of different implant surface properties on the morphology, proliferation, neurotrophin secretion, and gene expression of Schwann cells. Four types of implant surfaces, including ground (smooth surface), sandblasted and acid-etched (SLA), hydroxyapatite-coated (HA), and titanium plasma spray (TPS) surfaces were fabricated and photographed by a scanning electron microscopy (SEM). Schwann cells derived from neonatal rats were cultured on the implant surfaces and assessed via SEM observation and methylthiazol tetrazolium (MTT) colorimetric assay. The secretions and mRNA levels of brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) were measured by enzyme-linked immunosorbent assay (ELISA) and quantitative real time RT-PCR, respectively, on days 3 and 7. Tissue culture plastic was used as a control. The results demonstrated that Schwann cells exhibited typical bipolar spindle morphology on various surfaces, and proliferated faster than the control. Neurotrophin secretion and gene expression of both BDNF and NGF were also increased by implant surfaces. This study suggests that the function of Schwann cells can be enhanced by implant implants.

  5. The effect of plasma surface treatment on the bioactivity of titanium implant materials (in vitro).

    PubMed

    Abdelrahim, Ramy A; Badr, Nadia A; Baroudi, Kusai

    2016-01-01

    The surface of an implantable biomaterial plays a very important role in determining the biocompatibility, osteoinduction, and osteointegration of implants because it is in intimate contact with the host bone and soft tissues. This study was aimed to assess the effect of plasma surface treatment on the bioactivity of titanium alloy (Ti-6Al-4V). Fifteen titanium alloy samples were used in this study. The samples were divided into three groups (with five samples in each group). Five samples were kept untreated and served as control (group A). Another five plasma samples were sprayed for nitrogen ion implantation on their surfaces (group B) and the last five samples were pre-etched with acid before plasma treatment (group C). All the investigated samples were immersed for 7 days in Hank's balanced salt solution (HBSS) which was used as a simulating body fluid (SBF) at pH 7.4 and 37°C. HBSS was renewed every 3 days. The different surfaces were characterized by X-ray diffraction (XRD), Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDXA), and Fourier Transformation Infrared Spectroscopy (FTIR). Nitriding of Ti-alloy samples via plasma nitrogen ion implantation increased the bioactivity of titanium. Moreover, the surface topography affected the chemical structure of the formed apatite. Increasing the surface roughness enhanced the bioactivity of the implant material. Nitridation can be exploited as an effective way to promote the formation of bone-like material on the implant surface.

  6. Solar Wind Implantation into Lunar Regolith: Hydrogen Retention in a Surface with Defects

    NASA Technical Reports Server (NTRS)

    Farrell, W. M.; Hurley, D. M.; Zimmerman, M. I.

    2014-01-01

    Solar wind protons are implanted directly into the top 100 nm of the lunar near-surface region, but can either quickly diffuse out of the surface or be retained, depending upon surface temperature and the activation energy, U, associated with the implantation site. In this work, we explore the distribution of activation energies upon implantation and the associated hydrogen-retention times; this for comparison with recent observation of OH on the lunar surface. We apply a Monte Carlo approach: for simulated solar wind protons at a given local time, we assume a distribution of U values with a central peak, U(sub c) and width, U(sub w), and derive the fraction retained for long periods in the near-surface. We find that surfaces characterized by a distribution with predominantly large values of U (greater than 1 eV) like that expected at defect sites will retain implanted H (to likely form OH). Surfaces with the distribution predominantly at small values of U (less than 0.2 eV) will quickly diffuse away implanted H. However, surfaces with a large portion of activation energies between 0.3 eV less than U less than 0.9 eV will tend to be H-retentive in cool conditions but transform into H-emissive surfaces when warmed (as when the surface rotates into local noon). These mid-range activation energies give rise to a diurnal effect with diffusive loss of H at noontime.

  7. Solar wind implantation into lunar regolith: Hydrogen retention in a surface with defects

    NASA Astrophysics Data System (ADS)

    Farrell, W. M.; Hurley, D. M.; Zimmerman, M. I.

    2015-07-01

    Solar wind protons are implanted directly into the top 100 nm of the lunar near-surface region, but can either quickly diffuse out of the surface or be retained, depending upon surface temperature and the activation energy, U, associated with the implantation site. In this work, we explore the distribution of activation energies upon implantation and the associated hydrogen-retention times; this for comparison with recent observation of OH on the lunar surface. We apply a Monte Carlo approach: for simulated solar wind protons at a given local time, we assume a distribution of U values with a central peak, Uc and width, Uw, and derive the fraction retained for long periods in the near-surface. We find that surfaces characterized by a distribution with predominantly large values of U (>1 eV) like that expected at defect sites will retain implanted H (to likely form OH). Surfaces with the distribution predominantly at small values of U (<0.2 eV) will quickly diffuse away implanted H. However, surfaces with a large portion of activation energies between 0.3 eV < U < 0.9 eV will tend to be H-retentive in cool conditions but transform into H-emissive surfaces when warmed (as when the surface rotates into local noon). These mid-range activation energies give rise to a diurnal effect with diffusive loss of H at noontime.

  8. Solar Wind Implantation into Lunar Regolith: Hydrogen Retention in a Surface with Defects

    NASA Technical Reports Server (NTRS)

    Farrell, W. M.; Hurley, D. M.; Zimmerman, M. I.

    2014-01-01

    Solar wind protons are implanted directly into the top 100 nm of the lunar near-surface region, but can either quickly diffuse out of the surface or be retained, depending upon surface temperature and the activation energy, U, associated with the implantation site. In this work, we explore the distribution of activation energies upon implantation and the associated hydrogen-retention times; this for comparison with recent observation of OH on the lunar surface. We apply a Monte Carlo approach: for simulated solar wind protons at a given local time, we assume a distribution of U values with a central peak, U(sub c) and width, U(sub w), and derive the fraction retained for long periods in the near-surface. We find that surfaces characterized by a distribution with predominantly large values of U (greater than 1 eV) like that expected at defect sites will retain implanted H (to likely form OH). Surfaces with the distribution predominantly at small values of U (less than 0.2 eV) will quickly diffuse away implanted H. However, surfaces with a large portion of activation energies between 0.3 eV less than U less than 0.9 eV will tend to be H-retentive in cool conditions but transform into H-emissive surfaces when warmed (as when the surface rotates into local noon). These mid-range activation energies give rise to a diurnal effect with diffusive loss of H at noontime.

  9. Review found little difference between sandblasted and acid-etched (SLA) dental implants and modified surface (SLActive) implants.

    PubMed

    Stafford, Gary L

    2014-09-01

    Medline, Embase, the Cochrane Oral Health Group's Trials Register and OpenGREY databases were searched together with the reference lists of identified articles. Randomised controlled trials (RCTs) and prospective cohort studies of at least six month duration were included. Studies/case series in which there was only one implant surface (SLA or SLActive) and one loading protocol (immediate or early) were also considered. Two reviewers screened, selected and abstracted data, independently. RCTs were assessed for quality using the Cochrane risk of bias approach and observational studies using the Newcastle-Ottawa scale (NOS). The primary outcomes were changes from baseline to follow-up of clinical attachment level (CAL), probing depth (PD) and radiographic changes in the peri-implant bone level and number of implants lost. Cumulative survival rates (%) of each included study were calculated. Twenty-three articles reporting 19 studies (seven RCTs; 12 prospective observational studies) were included. The seven RCTs included 407 patients with 853 implants (8% titanium plasma-sprayed, 41.5% SLA and 50.5% SLActive). Only one RCT was considered to be at low risk of bias, the others were considered to be at unclear risk. The 12 observational studies included 1394 SLA and 145 SLActive implants and were considered to be of medium methodological quality based on the NOS. A narrative summary of the studies was undertaken owing to marked heterogeneity of the loading periods, types of implants described and lack of occurrence of the outcome of interest. There were no significant differences reported in the studies in relation to implant loss or clinical parameters between the immediate/early loading and delayed loading protocols. Overall, 95% of SLA and 97% of SLActive implants still survive at the end of follow-up. Despite the positive findings achieved by the included studies, few RCTs were available for analysis for SLActive implants. Study heterogeneity, scarcity of data and

  10. Erosion protection and surface conductivity enhancement of TOR polymers by ImplantoxTM technology

    NASA Astrophysics Data System (ADS)

    Iskanderova, Z.; Kleiman, J.; Mojazza, B.; Sutton, M.

    2003-09-01

    The possibility to apply successfully the patented Implantox surface modification technology to P-containing TORLM and TORNC thin polymer films for additional improvement of their erosion resistance in simulated low Earth orbit environment, up to full protection, has been achieved and demonstrated. The importance of the appropriate choice of elements to be implanted and implantation conditions, derived by computer simulation in high-performance space-related polymers, has been confirmed experimentally through P, Si, and P+Si implantation. Following fast atomic oxygen exposure was performed in a ground-based space simulator, and compared to the results of oxygen plasma asher testing. Using complementary surface analysis techniques, it was shown that oxidative surface conversion represents the main mechanism of full protection in all cases of successful Implantox treatment. Strong decrease of surface resistivity was shown to be an additional positive outcome of ImplantoxTM treatment of space-related polymer films.

  11. Factors influencing patients' willingness to pay for new technologies in hip and knee implants.

    PubMed

    Schwarzkopf, Ran; Sagebin, Fabio M; Karia, Raj; Koenig, Karl M; Bosco, Joseph A; Slover, James D

    2013-03-01

    Rising implant prices and evolving technologies are important factors contributing to the increased cost of arthroplasty. Assessing how patients value arthroplasty, new technologies, and their perceived outcomes is critical in planning cost-effective care, as well as evaluating new-technologies. One hundred one patients undergoing arthroplasty took part in the survey. We captured demographics, spending practices, knowledge of implants, patient willingness to pay for implants, and preferences related to implant attributes. When patients were asked if they would be satisfied with "standard of care" prosthesis, 80% replied "no". When asked if they would pay for a higher than "standard of care" prosthesis, 86% replied "yes". The study demonstrated that patients, regardless of their socio-economic status, are not satisfied with standard of care implants when newer technologies are available, and they may be willing to share in the cost of their prosthesis. Patients also prefer the option to choose what they perceive to be a higher quality or innovative implant even if the "out of pocket" cost is higher.

  12. Bone healing at implants with different surface configurations: an experimental study in dogs.

    PubMed

    Beolchini, Marco; Lang, Niklaus P; Gómez Moreno, Gerardo; Iezzi, Giovanna; Botticelli, Daniele; Calvo Guirado, José Luis

    2016-02-01

    To study osseointegration of implants with surface modifications by the use of fluoroboric acid and/or H2 O2 installed in conventional sites or sites with circumferential marginal defects. Four implants with different surfaces were used. One basic surface (ZirTi(®)) was sandblasted with zirconium microspheres and acid etched additionally with hydrofluoric acid. A second surface was treated with fluoroboric acid instead of hydrofluoric acid. The remainder of the other two surfaces was additionally treated with H2O2. The edentulous mandibles of 6 foxhound dogs were used to randomly install 8.5-mm-long implants with the different surfaces and to study the histological healing after 1 and 3 months. To study osteoconductivity, additional four recipient sites were prepared with the coronal region being widened so that a 4 mm deep and 0.85 mm wide marginal defect resulted after the placement of the four implants with different surfaces. No filler material or membranes were used, and a fully submerged healing was allowed for 3 months. At the conventional sites, new bone formation ranged between 68.5% and 74.9% after 1 month. After 3 months, bone-to-implant contact ranged from 72.6% at the ZirTi(®) surface to 84.1% at the fluoroboric acid-treated implants, the difference being statistically significant. At the sites with marginal defects, bone formation ranged from 0.77 mm at the surface treated with fluoroboric acid and H2O2 , to 1.93 mm at the surface treated with fluoroboric acid alone. Fluoroboric acid treatment alone of titanium implant surfaces resulted in improved osseointegration and osteoconductivity after 3 months. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  13. Role of Osteogenic Coatings on Implant Surfaces in Promoting Bone-To-Implant Contact in Experimental Osteoporosis: A Systematic Review and Meta-Analysis.

    PubMed

    Ghanem, Alexis; Kellesarian, Sergio Varela; Abduljabbar, Tariq; Al-Hamoudi, Nawwaf; Vohra, Fahim; Javed, Fawad

    2017-10-01

    The aim of this systematic review and meta-analysis was to evaluate the role of osteogenic coatings (placement of a thin film of organic and inorganic osteoinductive and osteoproliferative materials) on implant surfaces in augmenting bone-to-implant contact (BIC) in osteoporotic bone. To answer the focused question "Do osteogenic coatings on implant surfaces increase BIC in osteoporotic bone?" PubMed/MEDLINE, EMBASE, ISI Web of Knowledge, Scopus, and Google-Scholar databases were searched till June 2017 using different combinations of the following key words: bone-to-implant contact, coating, implant surface, osseointegration, and osteoporosis. Letters to the Editor, review articles, case-reports/case-series, and commentaries were excluded. Six animal studies were included, in which osteoporosis was induced by bilateral ovariectomy. In all studies, implant surface roughness was increased by various osteogenic surface coatings including alumina, hydroxyapatite, calcium phosphate, and zoledronic acid. Five studies showed that bone volume and BIC are significantly higher around implants with coated surfaces than noncoated implants. In 1 study, there was no difference in BIC around coated and noncoated implants. Although experimental studies have shown that osteogenic coatings are effective in enhancing BIC, their clinical relevance requires further investigations.

  14. A Novel Multi-Phosphonate Surface Treatment of Titanium Dental Implants: A Study in Sheep

    PubMed Central

    von Salis-Soglio, Marcella; Stübinger, Stefan; Sidler, Michéle; Klein, Karina; Ferguson, Stephen J.; Kämpf, Käthi; Zlinszky, Katalin; Buchini, Sabrina; Curno, Richard; Péchy, Péter; Aronsson, Bjorn-Owe; von Rechenberg, Brigitte

    2014-01-01

    The aim of the present study was to evaluate a new multi-phosphonate surface treatment (SurfLink®) in an unloaded sheep model. Treated implants were compared to control implants in terms of bone to implant contact (BIC), bone formation, and biomechanical stability. The study used two types of implants (rough or machined surface finish) each with either the multi-phosphonate Wet or Dry treatment or no treatment (control) for a total of six groups. Animals were sacrificed after 2, 8, and 52 weeks. No adverse events were observed at any time point. At two weeks, removal torque showed significantly higher values for the multi-phosphonate treated rough surface (+32% and +29%, Dry and Wet, respectively) compared to rough control. At 52 weeks, a significantly higher removal torque was observed for the multi-phosphonate treated machined surfaces (+37% and 23%, Dry and Wet, respectively). The multi-phosphonate treated groups showed a positive tendency for higher BIC with time and increased new-old bone ratio at eight weeks. SEM images revealed greater amounts of organic materials on the multi-phosphonate treated compared to control implants, with the bone fracture (from the torque test) appearing within the bone rather than at the bone to implant interface as it occurred for control implants. PMID:25215424

  15. Engineered Chimeric Peptides as Antimicrobial Surface Coating Agents toward Infection-Free Implants

    PubMed Central

    Yazici, Hilal; O'Neill, Mary B.; Kacar, Turgay; Wilson, Brandon R.; Oren, E. Emre; Sarikaya, Mehmet; Tamerler, Candan

    2016-01-01

    Prevention of bacterial colonization and consequent biofilm formation remains a major challenge in implantable medical devices. Implant-associated infections are not only a major cause of implant failures but also their conventional treatment with antibiotics brings further complications due to the escalation in multidrug resistance to a variety of bacterial species. Owing to their unique properties, antimicrobial peptides (AMPs) have gained significant attention as effective agents to combat colonization of microorganisms. These peptides have been shown to exhibit a wide spectrum of activities with specificity to a target cell while having a low tendency for developing bacterial resistance. Engineering biomaterial surfaces that feature AMP properties, therefore, offer a promising approach to prevent implant infections. Here, we engineered a chimeric peptide with bifunctionality that both forms a robust solid-surface coating while presenting antimicrobial property. The individual domains of the chimeric peptides were evaluated for their solid-binding kinetics to titanium substrate as well as for their antimicrobial properties in solution. The antimicrobial efficacy of the chimeric peptide on the implant material was evaluated in vitro against infection by a variety of bacteria, including Streptococcus mutans, Staphylococcus. epidermidis, and Escherichia coli, which are commonly found in oral and orthopedic implant related surgeries. Our results demonstrate significant improvement in reducing bacterial colonization onto titanium surfaces below the detectable limit. Engineered chimeric peptides with freely displayed antimicrobial domains could be a potential solution for developing infection-free surfaces by engineering implant interfaces with highly reduced bacterial colonization property. PMID:26795060

  16. Engineered Chimeric Peptides as Antimicrobial Surface Coating Agents toward Infection-Free Implants.

    PubMed

    Yazici, Hilal; O'Neill, Mary B; Kacar, Turgay; Wilson, Brandon R; Oren, E Emre; Sarikaya, Mehmet; Tamerler, Candan

    2016-03-02

    Prevention of bacterial colonization and consequent biofilm formation remains a major challenge in implantable medical devices. Implant-associated infections are not only a major cause of implant failures but also their conventional treatment with antibiotics brings further complications due to the escalation in multidrug resistance to a variety of bacterial species. Owing to their unique properties, antimicrobial peptides (AMPs) have gained significant attention as effective agents to combat colonization of microorganisms. These peptides have been shown to exhibit a wide spectrum of activities with specificity to a target cell while having a low tendency for developing bacterial resistance. Engineering biomaterial surfaces that feature AMP properties, therefore, offer a promising approach to prevent implant infections. Here, we engineered a chimeric peptide with bifunctionality that both forms a robust solid-surface coating while presenting antimicrobial property. The individual domains of the chimeric peptides were evaluated for their solid-binding kinetics to titanium substrate as well as for their antimicrobial properties in solution. The antimicrobial efficacy of the chimeric peptide on the implant material was evaluated in vitro against infection by a variety of bacteria, including Streptococcus mutans, Staphylococcus. epidermidis, and Escherichia coli, which are commonly found in oral and orthopedic implant related surgeries. Our results demonstrate significant improvement in reducing bacterial colonization onto titanium surfaces below the detectable limit. Engineered chimeric peptides with freely displayed antimicrobial domains could be a potential solution for developing infection-free surfaces by engineering implant interfaces with highly reduced bacterial colonization property.

  17. Zinc ion implantation-deposition technique improves the osteoblast biocompatibility of titanium surfaces

    PubMed Central

    LIANG, YONGQIANG; XU, JUAN; CHEN, JING; QI, MENGCHUN; XIE, XUEHONG; HU, MIN

    2015-01-01

    The plasma immersion ion implantation and deposition (PIIID) technique was used to implant zinc (Zn) ions into smooth surfaces of pure titanium (Ti) disks for investigation of tooth implant surface modification. The aim of the present study was to evaluate the surface structure and chemical composition of a modified Ti surface following Zn ion implantation and deposition and to examine the effect of such modification on osteoblast biocompatibility. Using the PIIID technique, Zn ions were deposited onto the smooth surface of pure Ti disks. The physical structure and chemical composition of the modified surface layers were characterized by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS), respectively. In vitro culture assays using the MG-63 bone cell line were performed to determine the effects of Zn-modified Ti surfaces following PIIID on cellular function. Acridine orange staining was used to detect cell attachment to the surfaces and cell cycle analysis was performed using flow cytometry. SEM revealed a rough ‘honeycomb’ structure on the Zn-modified Ti surfaces following PIIID processing and XPS data indicated that Zn and oxygen concentrations in the modified Ti surfaces increased with PIIID processing time. SEM also revealed significantly greater MG-63 cell growth on Zn-modified Ti surfaces than on pure Ti surfaces (P<0.05). Flow cytometric analysis revealed increasing percentages of MG-63 cells in S phase with increasing Zn implantation and deposition, suggesting that MG-63 apoptosis was inhibited and MG-63 proliferation was promoted on Zn-PIIID-Ti surfaces. The present results suggest that modification with Zn-PIIID may be used to improve the osteoblast biocompatibility of Ti implant surfaces. PMID:25673139

  18. Modulating macrophage polarization with divalent cations in nanostructured titanium implant surfaces

    NASA Astrophysics Data System (ADS)

    Lee, Chung-Ho; Kim, Youn-Jeong; Jang, Je-Hee; Park, Jin-Woo

    2016-02-01

    Nanoscale topographical modification and surface chemistry alteration using bioactive ions are centrally important processes in the current design of the surface of titanium (Ti) bone implants with enhanced bone healing capacity. Macrophages play a central role in the early tissue healing stage and their activity in response to the implant surface is known to affect the subsequent healing outcome. Thus, the positive modulation of macrophage phenotype polarization (i.e. towards the regenerative M2 rather than the inflammatory M1 phenotype) with a modified surface is essential for the osteogenesis funtion of Ti bone implants. However, relatively few advances have been made in terms of modulating the macrophage-centered early healing capacity in the surface design of Ti bone implants for the two important surface properties of nanotopography and and bioactive ion chemistry. We investigated whether surface bioactive ion modification exerts a definite beneficial effect on inducing regenerative M2 macrophage polarization when combined with the surface nanotopography of Ti. Our results indicate that nanoscale topographical modification and surface bioactive ion chemistry can positively modulate the macrophage phenotype in a Ti implant surface. To the best of our knowledge, this is the first demonstration that chemical surface modification using divalent cations (Ca and Sr) dramatically induces the regenerative M2 macrophage phenotype of J774.A1 cells in nanostructured Ti surfaces. In this study, divalent cation chemistry regulated the cell shape of adherent macrophages and markedly up-regulated M2 macrophage phenotype expression when combined with the nanostructured Ti surface. These results provide insight into the surface engineering of future Ti bone implants that are harmonized between the macrophage-governed early wound healing process and subsequent mesenchymal stem cell-centered osteogenesis function.

  19. Surface drilling technologies for Mars

    NASA Technical Reports Server (NTRS)

    Blacic, J. D.; Rowley, J. C.; Cort, G. E.

    1986-01-01

    Rock drilling and coring conceptual designs for the surface activities associated with a manned Mars mission are proposed. Straightforward extensions of equipment and procedures used on Earth are envisioned for the sample coring and shallow high explosive shot holes needed for tunneling and seismic surveying. A novel rocket exhaust jet piercing method is proposed for very rapid drilling of shot holes required for explosive excavation of emergency radiation shelters. Summaries of estimated equipment masses and power requirements are provided, and the indicated rotary coring rigs are scaled from terrestrial equipment and use compressed CO2 from the Martian atmosphere for core bit cooling and cuttings removal. A mass of 120 kg and power of 3 kW(e) are estimated for a 10 m depth capability. A 100 m depth capacity core rig requires about 1150 kg and 32 km(e). The rocket exhaust jet equipment devised for shallow (3m) explosive emplacement shot holes requires no surface power beyond an electrical ignition system, and might have a 15 kg mass.

  20. A Review on the Wettability of Dental Implant Surfaces II: Biological and Clinical Aspects

    PubMed Central

    Gittens, Rolando A.; Scheideler, Lutz; Rupp, Frank; Hyzy, Sharon L.; Geis-Gerstorfer, Jürgen; Schwartz, Zvi; Boyan, Barbara D.

    2014-01-01

    Dental and orthopaedic implants have been under continuous advancement to improve their interactions with bone and ensure a successful outcome for patients. Surface characteristics such as surface topography and surface chemistry can serve as design tools to enhance the biological response around the implant, with in vitro, in vivo and clinical studies confirming their effects. However, the comprehensive design of implants to promote early and long-term osseointegration requires a better understanding of the role of surface wettability and the mechanisms by which it affects the surrounding biological environment. This review provides a general overview of the available information about the contact angle values of experimental and of marketed implant surfaces, some of the techniques used to modify surface wettability of implants, and results from in vitro and clinical studies. We aim to expand the current understanding on the role of wettability of metallic implants at their interface with blood and the biological milieu, as well as with bacteria, and hard and soft tissues. PMID:24709541

  1. Improvement of in vitro corrosion and cytocompatibility of biodegradable Fe surface modified by Zn ion implantation

    NASA Astrophysics Data System (ADS)

    Wang, Henan; Zheng, Yang; Li, Yan; Jiang, Chengbao

    2017-05-01

    Pure Fe was surface-modified by Zn ion implantation to improve the biodegradable behavior and cytocompatibility. Surface topography, chemical composition, corrosion resistance and cytocompatibility were investigated. Atomic force microscopy, auger electron spectroscopy and X-ray photoelectron spectroscopy results showed that Zn was implanted into the surface of pure Fe in the depth of 40-60 nm and Fe2O3/ZnO oxides were formed on the outmost surface. Electrochemical measurements and immersion tests revealed an improved degradable behavior for the Zn-implanted Fe samples. An approximately 12% reduction in the corrosion potential (Ecorr) and a 10-fold increase in the corrosion current density (icorr) were obtained after Zn ion implantation with a moderate incident ion dose, which was attributed to the enhanced pitting corrosion. The surface free energy of pure Fe was decreased by Zn ion implantation. The results of direct cell culture indicated that the short-term (4 h) cytocompatibility of MC3T3-E1 cells was promoted by the implanted Zn on the surface.

  2. Fission Surface Power Technology Development Status

    NASA Technical Reports Server (NTRS)

    Palac, Donald T.; Mason, Lee S.; Harlow, Scott

    2009-01-01

    With the potential future deployment of a lunar outpost there is expected to be a clear need for a high-power, lunar surface power source to support lunar surface operations independent of the day-night cycle, and Fission Surface Power (FSP) is a very effective solution for power levels above a couple 10 s of kWe. FSP is similarly enabling for the poorly illuminated surface of Mars. The power levels/requirements for a lunar outpost option are currently being studied, but it is known that cost is clearly a predominant concern to decision makers. This paper describes the plans of NASA and the DOE to execute an affordable fission surface power system technology development project to demonstrate sufficient technology readiness of an affordable FSP system so viable and cost-effective FSP system options will be available when high power lunar surface system choices are expected to be made in the early 2010s.

  3. 3D Metal Printing - Additive Manufacturing Technologies for Frameworks of Implant-Borne Fixed Dental Prosthesis.

    PubMed

    Revilla León, M; Klemm, I M; García-Arranz, J; Özcan, M

    2017-09-01

    An edentulous patient was rehabilitated with maxillary metal-ceramic and mandibular metal-resin implant-supported fixed dental prosthesis (FDP). Metal frameworks of the FDPs were fabricated using 3D additive manufacturing technologies utilizing selective laser melting (SLM) and electron beam melting (EBM) processes. Both SLM and EBM technologies were employed in combination with computer numerical control (CNC) post-machining at the implant interface. This report highlights the technical and clinical protocol for fabrication of FDPs using SLM and EBM additive technologies. Copyright© 2017 Dennis Barber Ltd.

  4. Implantable Smart Technologies (IST): Defining the 'Sting' in Data and Device.

    PubMed

    Haddow, Gill; Harmon, Shawn H E; Gilman, Leah

    2016-09-01

    In a world surrounded by smart objects from sensors to automated medical devices, the ubiquity of 'smart' seems matched only by its lack of clarity. In this article, we use our discussions with expert stakeholders working in areas of implantable medical devices such as cochlear implants, implantable cardiac defibrillators, deep brain stimulators and in vivo biosensors to interrogate the difference facets of smart in 'implantable smart technologies', considering also whether regulation needs to respond to the autonomy that such artefacts carry within them. We discover that when smart technology is deconstructed it is a slippery and multi-layered concept. A device's ability to sense and transmit data and automate medicine can be associated with the 'sting' of autonomy being disassociated from human control as well as affecting individual, group, and social environments.

  5. A phone-assistive device based on Bluetooth technology for cochlear implant users.

    PubMed

    Qian, Haifeng; Loizou, Philipos C; Dorman, Michael F

    2003-09-01

    Hearing-impaired people, and particularly hearing-aid and cochlear-implant users, often have difficulty communicating over the telephone. The intelligibility of telephone speech is considerably lower than the intelligibility of face-to-face speech. This is partly because of lack of visual cues, limited telephone bandwidth, and background noise. In addition, cellphones may cause interference with the hearing aid or cochlear implant. To address these problems that hearing-impaired people experience with telephones, this paper proposes a wireless phone adapter that can be used to route the audio signal directly to the hearing aid or cochlear implant processor. This adapter is based on Bluetooth technology. The favorable features of this new wireless technology make the adapter superior to traditional assistive listening devices. A hardware prototype was built and software programs were written to implement the headset profile in the Bluetooth specification. Three cochlear implant users were tested with the proposed phone-adapter and reported good speech quality.

  6. Fission Surface Power Technology Demonstration Unit

    NASA Image and Video Library

    2016-11-09

    NASA Glenn Technician Mark Springowski works on a 10-kilowatt Stirling Power Conversion Unit, which is part of the Fission Surface Power Technology Demonstration Unit. This is a system level demonstration of a surface power system, which could potentially be used to support manned missions to the moon or Mars. A flight system would use 180 kilowatt nuclear fission reactor and four Stirling PCU’s to produce 40 kW of electricity for manned surface missions.

  7. Industrial hygiene and control technology assessment of ion implantation operations.

    PubMed

    Ungers, L J; Jones, J H

    1986-10-01

    Ion implantation is a process used to create the functional units (pn junctions) of integrated circuits, photovoltaic (solar) cells and other semiconductor devices. During the process, ions of an impurity or a "dopant" material are created, accelerated and imbedded in wafers of silicon. Workers responsible for implantation equipment are believed to be at risk from exposure to both chemical (dopant compounds) and physical (ionizing radiation) agents. In an effort to characterize the chemical exposures, monitoring for chemical hazards was conducted near eleven ion implanters at three integrated circuit facilities, while ionizing radiation was monitored near four of these units at two of the facilities. The workplace monitoring suggests that ion implantation operators routinely are exposed to low-level concentrations of dopants. Although the exact nature of dopant compounds released to the work environment was not determined, area and personal samples taken during normal operating activities found concentrations of arsenic, boron and phosphorous below OSHA Permissible Exposure Limits (PELs) for related compounds; area samples collected during implanter maintenance activities suggest that a potential exists for more serious exposures. The results of badge dosimetry monitoring for ionizing radiation indicate that serious exposures are unlikely to occur while engineering controls remain intact. All emissions were detected at levels unlikely to result in exposures above the OSHA standard for the whole body (1.25 rems per calendar quarter). The success of existing controls in preventing worker exposures is discussed. Particular emphasis is given to the differential exposures likely to be experienced by operators and maintenance personnel.(ABSTRACT TRUNCATED AT 250 WORDS)

  8. Identification card and codification of the chemical and morphological characteristics of 14 dental implant surfaces.

    PubMed

    Dohan Ehrenfest, David M; Vazquez, Lydia; Park, Yeong-Joon; Sammartino, Gilberto; Bernard, Jean-Pierre

    2011-10-01

    Dental implants are commonly used in daily practice; however, most surgeons do not really know the characteristics of these biomedical devices they are placing in their patients. The objective of this work is to describe the chemical and morphological characteristics of 14 implant surfaces available on the market and to establish a simple and clear identification (ID) card for all of them, following the classification procedure developed in the Dohan Ehrenfest et al (2010) Codification (DEC) system. Fourteen implant surfaces were characterized: TiUnite (Nobel Biocare), Ospol (Ospol), Kohno HRPS (Sweden & Martina), Osseospeed (AstraTech), Ankylos (Dentsply Friadent), MTX (Zimmer), Promote (Camlog), BTI Interna (Biotechnology Institute), EVL Plus (SERF), Twinkon Ref (Tekka), Ossean (Intra-Lock), NanoTite (Biomet 3I), SLActive (ITI Straumann), Integra-CP/NanoTite (Bicon). Three samples of each implant were analyzed. Superficial chemical composition was analyzed using X-ray photoelectron spectroscopy/electron spectroscopy for chemical analysis, and the 100 nm in-depth profile was established using Auger electron spectroscopy. The microtopography was quantified using light interferometry. The general morphology and nanotopography were evaluated using a field emission-scanning electron microscope. Finally, the characterization code of each surface was established using the DEC system, and the main characteristics of each surface were summarized in a reader-friendly ID card. From a chemical standpoint, of the 14 different surfaces, 10 were based on a commercially pure titanium (grade 2 or 4), 3 on a titanium-aluminum alloy (grade 5 titanium), and one on a calcium phosphate core. Nine surfaces presented different forms of chemical impregnation or discontinuous coating of the titanium core, and 3 surfaces were covered with residual aluminablasting particles. Twelve surfaces presented different degrees of inorganic pollutions, and 2 presented a severe organic pollution

  9. Implant surface factors and bacterial adhesion: a review of the literature.

    PubMed

    Yeo, In-Sung; Kim, Ha-Young; Lim, Kyung Sub; Han, Jung-Suk

    2012-10-01

    The microbiota that forms on implant surfaces placed in the human body can be highly resistant to antimicrobial agents and in some cases cause life-threatening infections. Consequently, to limit bacterial attachment to these surfaces and thereby minimize the risk of implant infection, the process of biofilm formation and bacterial attachment must be well-understood. The oral environment is considered to be an excellent model for research into biofilm formation and implant infection, accounting for many studies carried out in the field of dental medicine. Those studies show that the roughness, free energy, and material characteristics of the implant surface largely determine initial bacterial adhesion. This article reviews the relevant literature on these aspects of biofilm formation.

  10. Surface and corrosion characteristics of carbon plasma implanted and deposited nickel-titanium alloy

    SciTech Connect

    Poon, R.W.Y.; Liu, X.Y.; Chung, C.Y.; Chu, P.K.; Yeung, K.W.K.; Lu, W.W.; Cheung, K.M.C.

    2005-05-01

    Nickel-titanium shape memory alloys (NiTi) are potentially useful in orthopedic implants on account of their super-elastic and shape memory properties. However, the materials are prone to surface corrosion and the most common problem is out-diffusion of harmful Ni ions from the substrate into body tissues and fluids. In order to improve the corrosion resistance and related surface properties, we used the technique of plasma immersion ion implantation and deposition to deposit an amorphous hydrogenated carbon coating onto NiTi and implant carbon into NiTi. Both the deposited amorphous carbon film and carbon plasma implanted samples exhibit much improved corrosion resistances and surface mechanical properties and possible mechanisms are suggested.

  11. Secondary stability assessment of titanium implants with an alkali-etched surface: a resonance frequency analysis study in beagle dogs.

    PubMed

    Strnad, Jakub; Urban, Karel; Povysil, Ctibor; Strnad, Zdenek

    2008-01-01

    This study was carried out to quantify the effect of an alkali-modified surface on implant stability during healing using an animal model. A total of 24 screw-shaped, self-tapping, commercially pure titanium dental implants, divided into a test group (implants with an alkali-modified surface or "biosurface") and a control group (implants with a turned, machined surface) were inserted without pretapping in the tibiae of 3 beagle dogs. The resonance frequency analysis method was used to measure the implant stability quotient (ISQ) 0, 1, 3, 9, and 12 weeks after implantation. The animals were sacrificed after 2, 5, and 12 weeks, and the bone-implant contact (BIC%) was evaluated histomorphometrically. The difference in the osseointegration rates (deltaISQ/deltahealing time) between the implants with alkali-modified surface (biosurface) and those with a turned, machined surface was evaluated as a mean of 0.843 ISQ/week within the first 9 weeks of healing. The mean increase in the secondary implant stability was found to be proportional to the mean increase in the BIC at healing period earlier than 5 weeks. The characteristics that differed between the implant surfaces, ie, specific surface area, contact angle, and hydroxylation/hydration, may represent factors that influence the rate of osseointegration and the secondary implant stability. The alkali-treated surface enhances the secondary stability in the early stages of healing compared to the turned, machined surface, as a consequence of faster BIC formation.

  12. Method For Plasma Source Ion Implantation And Deposition For Cylindrical Surfaces

    DOEpatents

    Fetherston, Robert P. , Shamim, Muhammad M. , Conrad, John R.

    1997-12-02

    Uniform ion implantation and deposition onto cylindrical surfaces is achieved by placing a cylindrical electrode in coaxial and conformal relation to the target surface. For implantation and deposition of an inner bore surface the electrode is placed inside the target. For implantation and deposition on an outer cylindrical surface the electrode is placed around the outside of the target. A plasma is generated between the electrode and the target cylindrical surface. Applying a pulse of high voltage to the target causes ions from the plasma to be driven onto the cylindrical target surface. The plasma contained in the space between the target and the electrode is uniform, resulting in a uniform implantation or deposition of the target surface. Since the plasma is largely contained in the space between the target and the electrode, contamination of the vacuum chamber enclosing the target and electrodes by inadvertent ion deposition is reduced. The coaxial alignment of the target and the electrode may be employed for the ion assisted deposition of sputtered metals onto the target, resulting in a uniform coating of the cylindrical target surface by the sputtered material. The independently generated and contained plasmas associated with each cylindrical target/electrode pair allows for effective batch processing of multiple cylindrical targets within a single vacuum chamber, resulting in both uniform implantation or deposition, and reduced contamination of one target by adjacent target/electrode pairs.

  13. Laser-induced novel patterns: As smart strain actuators for new-age dental implant surfaces

    NASA Astrophysics Data System (ADS)

    Çelen, Serap; Özden, Hüseyin

    2012-12-01

    Surface morphologies of titanium implants are of crucial importance for long-term mechanical adaptation for following implantation. One major problem is the stress shielding effect which originates from the mismatch of the bone and the implant elasticity. It is time for a paradigm shift and for an exploration of novel smart surfaces to prevent this problem. Several surface treatment methods have traditionally been used to modify the surface morphology of titanium dental implants. The laser micro-machining can be considered as a unique and promising, non-contact, no media, contamination free, and flexible treatment method for modifying surface properties of materials in the biomedical industry. The aim of the present study is two folds; to develop novel 3D smart surfaces which can be acted as strain actuators by nanosecond laser pulse energies and irradiation strategies. And analyze these smart surface morphologies using finite element methods in order to estimate their internal stiffness values which play a great role on stress shielding effect. Novel 3D smart strain actuators were prepared using an ytterbium fiber laser (λ = 1060 nm) with 200-250 ns pulse durations on commercial pure titanium dental implant material specimen surfaces and optimum operation parameters were suggested.

  14. Surface microstructure of dental implants before and after insertion: an in vitro study by means of scanning probe microscopy.

    PubMed

    Salerno, Marco; Itri, Angelo; Frezzato, Marco; Rebaudi, Alberto

    2015-06-01

    The surface microstructure of dental implants affects osseointegration, which makes their accurate topographic characterization important. We defined a procedure for evaluation of implant topography before (pre-) and after (post-) in vitro implantation test in bovine bone. The apical morphology of ten implants was analyzed in pre- and post-conditions using atomic force microscopy or 3D profilometry. We extracted four topographical parameters (two amplitude, 1 spatial, and 1 hybrid) and assessed the differences by analysis of variance. The implant with coating (Spline Twist MP-1 HA) was damaged. The two implants with highest pre-amplitude parameters (Pitt Easy VTPS, TLR3815) maintained their character on testing. Pitt Easy PURETEX and OT-F1 were the only nondamaged implants whose amplitude parameters increased. The surface area underwent minor changes even when the texture changed (Tri-Vent, Pitt Easy PURETEX, Exp #1). The implants that ranked the lowest in all parameters before implantation were DT4013TI, Tri-Vent, OT-F1, and Exp #2. On testing, DT4013TI showed the highest decrease in values, whereas Tri-Vent showed the highest increase in surface area. All the experimental implants showed similar topographic properties both pre- and post-test. For most implants, no major changes occurred in surface topography on implantation. The procedure applied seems promising to evaluate the degradation of implant surface on insertion.

  15. Adhesion of Candida albicans to various dental implant surfaces and the influence of salivary pellicle proteins.

    PubMed

    Bürgers, Ralf; Hahnel, Sebastian; Reichert, Torsten E; Rosentritt, Martin; Behr, Michael; Gerlach, Till; Handel, Gerhard; Gosau, Martin

    2010-06-01

    Dental implants may be considered a potential reservoir for (re)infection with oral Candida albicans. Our aim was to evaluate initial fungal adhesion to three differentially textured titanium and one zirconia implant surface, and to correlate these findings to differences in specific surface characteristics (surface roughness (R(a)) and surface free energy (SFE)). Additionally, we investigated the influence of salivary protein films and two pellicle proteins (mucin and albumin). Implant surfaces were characterized by perthometer (R(a)) and goniometer (SFE) measurements. Implant specimens were rinsed with human whole saliva, mucin, albumin, or phosphate buffered saline and incubated in C. albicans suspension for 2.5h. Adherent fungi were quantified by means of a bioluminometric assay. The lowest amount of fungal cells was found on sand-blasted titanium, whereas zirconia implants did not show any reduced potential to adhere C. albicans. The influence of the implant SFE on fungal biofilm formation appears to be more important than the influence of R(a). The protein mucin enhanced C. albicans accumulation. In contrast, albumin is unlikely to be involved in the adhesion process of C. albicans. Copyright 2010. Published by Elsevier Ltd.

  16. Explaining the Red Fluorescence Evident on the Surface of Failed Dental Implants: Case Reports.

    PubMed

    Ku, Hye-Min; Jun, Mi-Kyoung; Kim, Jee-Hwan; Kwon, Ho-Keun; Kim, Baek-Il

    2016-06-01

    It is important to identify the reasons for implant failure when planning future dental treatment. No studies have distinguished the factors that affect implant failure by evaluating the appearance of failed fixtures. This study investigated these factors by evaluating the surface of implant fixtures using quantitative light-induced fluorescence-digital (QLF-D), which involves detecting the red fluorescence emitted by porphyrin metabolized by oral bacteria in a mature biofilm. The areas of red fluorescence in QLF-D images obtained from all aspects of the fixture surface were then analyzed using quantitative analysis software. Red fluorescence was evident on the surface of implants that failed after at least 2 years of occlusal loading and exhibited severe bone loss. Implants with no fluorescence exhibited a clean surface in blue-light images, and the bone loss could not be observed radiographically. The cases presented that failed dental implant surfaces caused by periimplantitis can be detected by the red fluorescence evident as QLF-D.

  17. Lunar Surface Systems Supportability Technology Development Roadmap

    NASA Technical Reports Server (NTRS)

    Oeftering, Richard C.; Struk, Peter M.; Green, Jennifer L.; Chau, Savio N.; Curell, Philip C.; Dempsey, Cathy A.; Patterson, Linda P.; Robbins, William; Steele, Michael A.; DAnnunzio, Anthony; hide

    2011-01-01

    The Lunar Surface Systems Supportability Technology Development Roadmap is a guide for developing the technologies needed to enable the supportable, sustainable, and affordable exploration of the Moon and other destinations beyond Earth. Supportability is defined in terms of space maintenance, repair, and related logistics. This report considers the supportability lessons learned from NASA and the Department of Defense. Lunar Outpost supportability needs are summarized, and a supportability technology strategy is established to make the transition from high logistics dependence to logistics independence. This strategy will enable flight crews to act effectively to respond to problems and exploit opportunities in an environment of extreme resource scarcity and isolation. The supportability roadmap defines the general technology selection criteria. Technologies are organized into three categories: diagnostics, test, and verification; maintenance and repair; and scavenge and recycle. Furthermore, "embedded technologies" and "process technologies" are used to designate distinct technology types with different development cycles. The roadmap examines the current technology readiness level and lays out a four-phase incremental development schedule with selection decision gates. The supportability technology roadmap is intended to develop technologies with the widest possible capability and utility while minimizing the impact on crew time and training and remaining within the time and cost constraints of the program.

  18. Zinc-ion implanted and deposited titanium surfaces reduce adhesion of Streptococccus mutans

    NASA Astrophysics Data System (ADS)

    Xu, Juan; Ding, Gang; Li, Jinlu; Yang, Shenhui; Fang, Bisong; Sun, Hongchen; Zhou, Yanmin

    2010-10-01

    While titanium (Ti) is a commonly used dental implant material with advantageous biocompatible and mechanical properties, native Ti surfaces do not have the ability to prevent bacterial colonization. The objective of this study was to evaluate the chemical composition and bacterial adhesive properties of zinc (Zn) ion implanted and deposited Ti surfaces (Zn-PIIID-Ti) as potential dental implant materials. Surfaces of pure Ti (cp-Ti) were modified with increasing concentrations of Zn using plasma immersion ion implantation and deposition (PIIID), and elemental surface compositions were characterized by X-ray photoelectron spectrometry (XPS). To evaluate bacterial responses, Streptococcus mutans were seeded onto the modifiedTi surfaces for 48 h and subsequently observed by scanning electron microscopy. Relative numbers of bacteria on each surface were assessed by collecting the adhered bacteria, reculturing and counting colony forming units after 48 h on bacterial grade plates. Ti, oxygen and carbon elements were detected on all surfaces by XPS. Increased Zn signals were detected on Zn-PIIID-Ti surfaces, correlating with an increase of Zn-deposition time. Substantial numbers of S. mutans adhered to cp-Ti samples, whereas bacterial adhesion on Zn-PIIID-Ti surfaces signficantly decreased as the Zn concentration increased ( p < 0.01). In conclusion, PIIID can successfully introduce Zn onto a Ti surface, forming a modified surface layer bearing Zn ions that consequently deter adhesion of S. mutans, a common bacterium in the oral environment.

  19. Effect of cleaning and sterilization on titanium implant surface properties and cellular response

    PubMed Central

    Park, Jung Hwa; Olivares-Navarrete, Rene; Baier, Robert E.; Meyer, Anne E.; Tannenbaum, Rina; Boyan, Barbara D.; Schwartz, Zvi

    2013-01-01

    Titanium (Ti) has been widely used as an implant material due to the excellent biocompatibility and corrosion resistance of its oxide surface. Biomaterials must be sterile before implantation, but the effects of sterilization on their surface properties have been less well studied. The effects of cleaning and sterilization on surface characteristics were bio-determined using contaminated and pure Ti substrata first manufactured to present two different surface structures: pretreated titanium (PT, Ra = 0.4 μm) (i.e. surfaces that were not modified by sandblasting and/or acid etching); (SLA, Ra = 3.4 μm). Previously cultured cells and associated extracellular matrix were removed from all bio-contaminated specimens by cleaning in a sonicator bath with a sequential acetone–isopropanol–ethanol–distilled water protocol. Cleaned specimens were sterilized with autoclave, gamma irradiation, oxygen plasma, or ultraviolet light. X-ray photoelectron spectroscopy (XPS), contact angle measurements, profilometry, and scanning electron microscopy were used to examine surface chemical components, hydrophilicity, roughness, and morphology, respectively. Small organic molecules present on contaminated Ti surfaces were removed with cleaning. XPS analysis confirmed that surface chemistry was altered by both cleaning and sterilization. Cleaning and sterilization affected hydrophobicity and roughness. These modified surface properties affected osteogenic differentiation of human MG63 osteoblast-like cells. Specifically, autoclaved SLA surfaces lost the characteristic increase in osteoblast differentiation seen on starting SLA surfaces, which was correlated with altered surface wettability and roughness. These data indicated that recleaned and resterilized Ti implant surfaces cannot be considered the same as the first surfaces in terms of surface properties and cell responses. Therefore, the reuse of Ti implants after resterilization may not result in the same tissue responses as

  20. A graphene/zinc oxide nanocomposite film protects dental implant surfaces against cariogenic Streptococcus mutans.

    PubMed

    Kulshrestha, Shatavari; Khan, Shakir; Meena, Ramovatar; Singh, Braj R; Khan, Asad U

    2014-01-01

    Oral biofilms play a crucial role in the development of dental caries and other periodontal diseases. Streptococcus mutans is one of the primary etiological agents in dental caries. Implant systems are regularly employed to replace missing teeth. Oral biofilms accumulate on these implants and are the chief cause of dental implant failure. In the present study, the potential of graphene/zinc oxide nanocomposite (GZNC) against the cariogenic properties of Streptococcus mutans was explored and the anti-biofilm behaviour of artificial acrylic teeth surfaces coated with GZNC was examined. Acrylic teeth are a good choice for implants as they are low cost, have low density and can resist fracture. Microscopic studies and anti-biofilm assays showed a significant reduction in biofilm in the presence GZNC. GZNC was also found to be nontoxic against HEK-293 (human embryonic kidney cell line). The results indicate the potential of GZNC as an effective coating agent for dental implants by efficiently inhibiting S. mutans biofilms.

  1. MicroCT Analysis of Micro-Nano Titanium Implant Surface on the Osseointegration.

    PubMed

    Ban, Jaesam; Kang, Seongsoo; Kim, Jihyun; Lee, Kwangmin; Hyunpil, Lim; Vang, Mongsook; Yang, Hongso; Oh, Gyejeong; Kim, Hyunseung; Hwang, Gabwoon; Jung, Yongho; Lee, Kyungku; Park, Sangwon; Yunl, Kwidug

    2015-01-01

    This study was to investigate the effects of micro-nano titanium implant surface on the osseointegration. A total of 36 screw-shaped implants were used. The implant surfaces were classified into 3 groups (n = 12): machined surface (M group), nanosurface which is nanotube formation on the machined surface (MA group) and nano-micro surface which is nanotube formation on the RBM surface (RA group). Anodic oxidation was performed at a 20 V for 10 min with 1 M H3PO4 and 1.5 wt% HF solutions. The implants were installed on the humerus on 6 beagles. After 4 and 12 weeks, the morphometric analysis with micro CT (skyscan 1172, SKYSCAN, Antwerpen, Belgium) was done. The data were statistically analyzed with two-way ANOVA. Bone mineral density and bone volume were significantly increased depending on time. RA group showed the highest bone mineral density and bone volume at 4 weeks and 12 weeks significantly. It indicated that nano-micro titanium implant surface showed faster and more mature osseointegration.

  2. Surface Damage on Dental Implants with Release of Loose Particles after Insertion into Bone.

    PubMed

    Senna, Plinio; Antoninha Del Bel Cury, Altair; Kates, Stephen; Meirelles, Luiz

    2015-08-01

    Modern dental implants present surface features of distinct dimensions that can be damaged during the insertion procedure into bone. The aims of this study were (1) to quantify by means of roughness parameters the surface damage caused by the insertion procedure of dental implants and (2) to investigate the presence of loose particles at the interface. Three groups of dental implants representing different surface topographies were inserted in fresh cow rib bone blocks. The surface roughness was characterized by interferometry on the same area before and after the insertion. Scanning electron microscopy (SEM)-back-scattered electron detector (BSD) analysis was used to identify loose particles at the interface. The amplitude and hybrid roughness parameters of all three groups were lower after insertion. The surface presenting predominance of peaks (Ssk [skewness] > 0) associated to higher structures (height parameters) presented higher damage associated to more pronounced reduction of material volume. SEM-BSD images revealed loose titanium and aluminum particles at the interface mainly at the crestal cortical bone level. Shearing forces during the insertion procedure alters the surface of dental implants. Loose metal particles can be generated at bone-implant interface especially around surfaces composed mainly by peaks and with increased height parameters. © 2013 Wiley Periodicals, Inc.

  3. Nanocoating of titanium implant surfaces with organic molecules. Polysaccharides including glycosaminoglycans.

    PubMed

    Gurzawska, Katarzyna; Svava, Rikke; Jørgensen, Niklas Rye; Gotfredsen, Klaus

    2012-12-01

    Long-term stability of titanium implants are dependent on a variety of factors. Nanocoating with organic molecules is one of the method used to improve osseointegration. Nanoscale modification of titanium implants affects surface properties, such as hydrophilicity, biochemical bonding capacity and roughness. This influences cell behaviour on the surface such as adhesion, proliferation and differentiation of cells as well as the mineralization of the extracellular matrix at the implant surfaces. The aim of the present systematic review was to describe organic molecules used for surface nanocoating with focus on polysaccharides including glycosaminoglycans, and how these molecules change surface properties, cell reactions and affect on osseointegartion. The included in vitro studies demonstrated increased cell adhesion, proliferation and mineralization of a number of the tested polysaccharide nanocoatings. The included in vivo studies, showed improvement of bone interface reactions measured as increased Bone-to-Implant Contact length and Bone Mineral Density adjacent to the polysaccharide coated surfaces. Based on existing literature, surface modification with polysaccharide and glycosaminoglycans appears to be an effective way to stimulate bone regeneration on bone-implant interface.

  4. Current trends in dental implants

    PubMed Central

    Gaviria, Laura; Salcido, John Paul; Guda, Teja

    2014-01-01

    Tooth loss is very a very common problem; therefore, the use of dental implants is also a common practice. Although research on dental implant designs, materials and techniques has increased in the past few years and is expected to expand in the future, there is still a lot of work involved in the use of better biomaterials, implant design, surface modification and functionalization of surfaces to improve the long-term outcomes of the treatment. This paper provides a brief history and evolution of dental implants. It also describes the types of implants that have been developed, and the parameters that are presently used in the design of dental implants. Finally, it describes the trends that are employed to improve dental implant surfaces, and current technologies used for the analysis and design of the implants. PMID:24868501

  5. Ion Implant Technology for Intermediate Band Solar Cells

    NASA Astrophysics Data System (ADS)

    Olea, Javier; Pastor, David; Luque, María Toledano; Mártil, Ignacio; Díaz, Germán González

    This chapter describes the creation of an Intermediate Band (IB) on single crystal silicon substrates by means of high-dose Ti implantation and subsequent Pulsed Laser Melting (PLM). The Ti concentration over the Mott limit is confirmed by Time-of-Flight Secondary Ion Mass Spectroscopy (ToF-SIMS) measurements and the recovery of the crystallinity after annealing by means of Glancing Incidence X Ray Diffraction (GIXRD) and Transmission Electron Microscopy (TEM). Rutherford Backscattering Spectroscopy (RBS) measurements show that most of the atoms are located interstitially. Analysis of the sheet resistance and mobility measured using the van der Pauw geometry shows a temperature-dependent decoupling between the implanted layer and the substrate. This decoupling and the high laminated conductivity of the implanted layer could not be explained except if we assume that an IB has been formed in the semiconductor. A specific model for the bilayer electrical behaviour has been developed. The fitting of this model and also the simulation of the sheet resistance with the ATLAS code allow to determine that the IB energetic position is located around 0.36-0.38 eV below the conduction band. Carriers at the IB have a density very similar to the Ti concentration and behave as holes with mobilities as low as 0.4 cm2 Vs- 1.

  6. In Vitro Evaluation of the Effects of Multiple Oral Factors on Dental Implants Surfaces.

    PubMed

    Sridhar, Sathyanarayanan; Abidi, Zain; Wilson, Thomas G; Valderrama, Pilar; Wadhwani, Chandur; Palmer, Kelli; Rodrigues, Danieli C

    2016-06-01

    Presence of metal ions and debris resulting from corrosion processes of dental implants in vivo can elicit adverse tissue reactions, possibly leading to peri-implant bone loss and eventually implant failure. This study hypothesized that the synergistic effects of bacterial biofilm and micromotion can cause corrosion of dental implants and release of metal ions in vivo. The goal is to simulate the oral environment where an implant will be exposed to a combination of acidic electrochemical environment and mechanical forces. Four conditions were developed to understand the individual and synergistic effects of mechanical forces and bacterial biofilm on the surface of dental implants; In condition 1, it was found that torsional forces during surgical insertion did not generate wear particle debris or metal ions. In condition 2, fatigue tests were performed in a wet environment to evaluate the effect of cyclic occlusal forces. The mechanical forces applied on the implants were able to cause implant fracture as well as surface corrosion features such as discoloration, delamination, and fatigue cracks. Immersion testing (condition 3) showed that bacteria ( Streptococcus mutans ) were able to create an acidic condition that triggered surface damage such as discoloration, rusting, and pitting. A novel testing setup was developed to understand the conjoint effects of micromotion and bacterial biofilm (condition 4). Surface damage initiated by acidic condition due to bacteria (condition 3), can be accelerated in tandem with mechanical forces through fretting-crevice corrosion. Permanent damage to surface layers can affect osseointegration and deposition of metal ions in the surrounding tissues can trigger inflammation.

  7. Technological, biological, and acoustical constraints to music perception in cochlear implant users.

    PubMed

    Limb, Charles J; Roy, Alexis T

    2014-02-01

    Despite advances in technology, the ability to perceive music remains limited for many cochlear implant users. This paper reviews the technological, biological, and acoustical constraints that make music an especially challenging stimulus for cochlear implant users, while highlighting recent research efforts to overcome these shortcomings. The limitations of cochlear implant devices, which have been optimized for speech comprehension, become evident when applied to music, particularly with regards to inadequate spectral, fine-temporal, and dynamic range representation. Beyond the impoverished information transmitted by the device itself, both peripheral and central auditory nervous system deficits are seen in the presence of sensorineural hearing loss, such as auditory nerve degeneration and abnormal auditory cortex activation. These technological and biological constraints to effective music perception are further compounded by the complexity of the acoustical features of music itself that require the perceptual integration of varying rhythmic, melodic, harmonic, and timbral elements of sound. Cochlear implant users not only have difficulty perceiving spectral components individually (leading to fundamental disruptions in perception of pitch, melody, and harmony) but also display deficits with higher perceptual integration tasks required for music perception, such as auditory stream segregation. Despite these current limitations, focused musical training programs, new assessment methods, and improvements in the representation and transmission of the complex acoustical features of music through technological innovation offer the potential for significant advancements in cochlear implant-mediated music perception. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Temperature evaluation of dental implant surface irradiated with high-power diode laser.

    PubMed

    Rios, F G; Viana, E R; Ribeiro, G M; González, J C; Abelenda, A; Peruzzo, D C

    2016-09-01

    The prevalence of peri-implantitis and the absence of a standard approach for decontamination of the dental implant surface have led to searches for effective therapies. Since the source of diode lasers is portable, has reduced cost, and does not cause damage to the titanium surface of the implant, high-power diode lasers have been used for this purpose. The effect of laser irradiation on the implants is the elevation of the temperature surface. If this elevation exceeds 47 °C, the bone tissue is irreversibly damaged, so for a safety therapy, the laser parameters should be controlled. In this study, a diode laser of GaAsAl was used to irradiate titanium dental implants, for powers 1.32 to 2.64 W (real) or 2.00 to 4.00 W (nominal), in continuous/pulsed mode DC/AC, with exposure time of 5/10 s, with/without air flow for cooling. The elevation of the temperature was monitored in real time in two positions: cervical and apical. The best results for decontamination using a 968-nm diode laser were obtained for a power of 1.65 and 1.98 W (real) for 10 s, in DC or AC mode, with an air flow of 2.5 l/min. In our perspective in this article, we determine a suggested approach for decontamination of the dental implant surface using a 968-nm diode laser.

  9. Frictional and bone ingrowth properties of engineered surface topographies produced by electron beam technology.

    PubMed

    Biemond, J Elizabeth; Aquarius, René; Verdonschot, Nico; Buma, Pieter

    2011-05-01

    Electron beam melting (E-beam) is a new technology to produce 3-dimensional surface topographies for cementless orthopedic implants. The friction coefficients of two newly developed E-beam produced surface topographies were in vitro compared with sandblasted E-beam and titanium plasma sprayed controls. Bone ingrowth (direct bone-implant contact) was determined by implanting the samples in the femoral condyles of 6 goats for a period of 6 weeks. Friction coefficients of the new structures were comparable to the titanium plasma sprayed control. The direct bone-implant contact was 23.9 and 24.5% for the new surface structures. Bone-implant contact of the sandblasted and titanium plasma sprayed control was 18.2 and 25.5%, respectively. The frictional and bone ingrowth properties of the E-beam produced surface structures are similar to the plasma-sprayed control. However, since the maximal bone ingrowth had not been reached for the E-beam structures during the relatively short-term period, longer-term follow-up studies are needed to assess whether the E-beam structures lead to a better long-term performance than surfaces currently in use, such as titanium plasma spray coating.

  10. Biomechanical evaluation and surface characterization of a nano-modified surface on PEEK implants: a study in the rabbit tibia

    PubMed Central

    Johansson, Pär; Jimbo, Ryo; Kjellin, Per; Currie, Fredrik; Chrcanovic, Bruno Ramos; Wennerberg, Ann

    2014-01-01

    Polyether ether ketone (PEEK) is today frequently used as a biomaterial in different medical operations due to its excellent mechanical and chemical properties. However, the untreated surface of PEEK is bioinert and hydrophobic, and it does not osseointegrate in its pure form. The aim of this study was to evaluate a unique nano-modified surface of PEEK with respect to osseointegration. Forty-eight threaded, non-cutting PEEK implants were inserted bilaterally in the tibia of 24 rabbits. Half of the implants (n=24) were coated with nanocrystalline hydroxyapatite (test) and the remaining implants (n=24) were left uncoated (control). Half of the animals (n=12) were euthanized after 3 weeks of healing and the remaining (n=12) after 12 weeks. The implant retention was measured with a removal torque apparatus. Surface analysis was performed with interferometry, scanning electron microscopy, and X-ray photon spectroscopy to relate the removal torque to the applied surface. The test implants revealed a significantly higher retention after 3 weeks (P=0.05) and 12 weeks (P=0.028) compared to controls. The result of the present study proves that the addition of nanocrystalline hydroxyapatite coating to PEEK surfaces significantly increases its removal torque and biocompatibility. PMID:25152620

  11. Bone regeneration at implants with turned or rough surfaces in self-contained defects. An experimental study in the dog.

    PubMed

    Botticelli, Daniele; Berglundh, Tord; Persson, Leif G; Lindhe, Jan

    2005-05-01

    Marginal hard tissue defects present at implants with a rough surface can heal with a high degree of bone fill and osseointegration. The healing of similar defects adjacent to implants with a smooth surface appears to be less predictable. The aim was to compare bone healing at implants with turned or rough surface topographies placed in self-contained defects using either a submerged or non-submerged installation technique. Six dogs were used. Three months after tooth extraction four experimental sites were prepared for implant installation in both sides of the mandible. The marginal 5 mm of the canal prepared for the implant was widened. Thus, following implant placement a circumferential gap occurred between the bone tissue and the implant surface that was between 1 and 1.25 mm wide. In each side of the mandible two implants with a turned surface and two implants with a rough surface were installed. The implants in the right side were fully submerged, while a non-submerged technique was applied in the left side. The animals were sacrificed 4 months later, block biopsies of each implant site were dissected and ground as well as paraffin sections were prepared. The marginal defects around rough surface implants exhibited after 4 months of healing substantial bone fill and a high degree of osseointegration following either the submerged or the non-submerged installation technique. Healing at turned implants was characterized by incomplete bone fill and the presence of a connective tissue zone between the implant and the newly formed bone. The distance between the implant margin (M) and the most coronal level of bone-to-implant contact (B) at implants with a rough surface was 0.84+/-0.37 mm at submerged and 0.90+/-0.39 mm at non-submerged sites. The distance M-B at implants with a turned surface was 3.39+/-0.52 mm at submerged and 3.23+/-0.68 mm at non-submerged sites. The differences between the rough and turned implants regarding the length of distance M-B were

  12. Oriented collagen as a potential cochlear implant electrode surface coating to achieve directed neurite outgrowth.

    PubMed

    Volkenstein, Stefan; Kirkwood, John E; Lai, Edwina; Dazert, Stefan; Fuller, Gerald G; Heller, Stefan

    2012-04-01

    In patients with severe to profound hearing loss, cochlear implants (CIs) are currently the only therapeutic option when the amplification with conventional hearing aids does no longer lead to a useful hearing experience. Despite its great success, there are patients in which benefit from these devices is rather limited. One reason may be a poor neuron-device interaction, where the electric fields generated by the electrode array excite a wide range of tonotopically organized spiral ganglion neurons at the cost of spatial resolution. Coating of CI electrodes to provide a welcoming environment combined with suitable surface chemistry (e.g. with neurotrophic factors) has been suggested to create a closer bioelectrical interface between the electrode array and the target tissue, which might lead to better spatial resolution, better frequency discrimination, and ultimately may improve speech perception in patients. Here we investigate the use of a collagen surface with a cholesteric banding structure, whose orientation can be systemically controlled as a guiding structure for neurite outgrowth. We demonstrate that spiral ganglion neurons survive on collagen-coated surfaces and display a directed neurite growth influenced by the direction of collagen fibril deposition. The majority of neurites grow parallel to the orientation direction of the collagen. We suggest collagen coating as a possible future option in CI technology to direct neurite outgrowth and improve hearing results for affected patients.

  13. Regulatory science of new technology: tendency of medical professionals' interests on silicone breast implants.

    PubMed

    Nakazaki, Tomomichi; Ikeda, Koji; Iwasaki, Kiyotaka; Umezu, Mitsuo

    2016-09-01

    New technology related to artificial organs is most attractive for worldwide researchers. We believe they must contribute for the future patients against untreatable diseases. Regulatory science is a new science to establish 'social acceptance' of new technology into the clinical market as soon as possible. In the history of silicone breast implants, we could recognize risks many times; however, we missed such chances to prevent a subsequent crisis. We analyzed the trend of published literature related to silicone breast implants to review the medical professionals' interests on such risks. This trend showed, despite issues of a social acceptance of silicone breast implants in a few countries, other countries' medical professionals had no interest. Our hypothesis is 'medical professionals face the government and do not have contributed to re-establish the social acceptance of new technologies for patients'. Any technology does not have the complete evidence of safety, efficacy and quality, despite regulatory authorities' review and approval with clinical evidences. medical professionals need to conduct subsequently the epidemiological study, to take a meta-analysis periodically and to create/update the guidance for their patients under their professional ethics after the marketing of new technologies. We need to take seriously the 'lesson learned' from the history of silicone breast implants for all kind of new technologies existed in the present.

  14. Molecular dynamics study on splitting of hydrogen-implanted silicon in Smart-Cut® technology

    NASA Astrophysics Data System (ADS)

    Bing, Wang; Bin, Gu; Rongying, Pan; Sijia, Zhang; Jianhua, Shen

    2015-03-01

    Defect evolution in a single crystal silicon which is implanted with hydrogen atoms and then annealed is investigated in the present paper by means of molecular dynamics simulation. By introducing defect density based on statistical average, this work aims to quantitatively examine defect nucleation and growth at nanoscale during annealing in Smart-Cut® technology. Research focus is put on the effects of the implantation energy, hydrogen implantation dose and annealing temperature on defect density in the statistical region. It is found that most defects nucleate and grow at the annealing stage, and that defect density increases with the increase of the annealing temperature and the decrease of the hydrogen implantation dose. In addition, the enhancement and the impediment effects of stress field on defect density in the annealing process are discussed. Project supported by the National Natural Science Foundation of China (No. 11372261), the Excellent Young Scientists Supporting Project of Science and Technology Department of Sichuan Province (No. 2013JQ0030), the Supporting Project of Department of Education of Sichuan Province (No. 2014zd3132), the Opening Project of Key Laboratory of Testing Technology for Manufacturing Process, Southwest University of Science and Technology-Ministry of Education (No. 12zxzk02), the Fund of Doctoral Research of Southwest University of Science and Technology (No. 12zx7106), and the Postgraduate Innovation Fund Project of Southwest University of Science and Technology (No. 14ycxjj0121).

  15. Fission Surface Power Technology Development Update

    NASA Technical Reports Server (NTRS)

    Palac, Donald T.; Mason, Lee S.; Houts, Michael G.; Harlow, Scott

    2011-01-01

    Power is a critical consideration in planning exploration of the surfaces of the Moon, Mars, and places beyond. Nuclear power is an important option, especially for locations in the solar system where sunlight is limited or environmental conditions are challenging (e.g., extreme cold, dust storms). NASA and the Department of Energy are maintaining the option for fission surface power for the Moon and Mars by developing and demonstrating technology for a fission surface power system. The Fission Surface Power Systems project has focused on subscale component and subsystem demonstrations to address the feasibility of a low-risk, low-cost approach to space nuclear power for surface missions. Laboratory demonstrations of the liquid metal pump, reactor control drum drive, power conversion, heat rejection, and power management and distribution technologies have validated that the fundamental characteristics and performance of these components and subsystems are consistent with a Fission Surface Power preliminary reference concept. In addition, subscale versions of a non-nuclear reactor simulator, using electric resistance heating in place of the reactor fuel, have been built and operated with liquid metal sodium-potassium and helium/xenon gas heat transfer loops, demonstrating the viability of establishing system-level performance and characteristics of fission surface power technologies without requiring a nuclear reactor. While some component and subsystem testing will continue through 2011 and beyond, the results to date provide sufficient confidence to proceed with system level technology readiness demonstration. To demonstrate the system level readiness of fission surface power in an operationally relevant environment (the primary goal of the Fission Surface Power Systems project), a full scale, 1/4 power Technology Demonstration Unit (TDU) is under development. The TDU will consist of a non-nuclear reactor simulator, a sodium-potassium heat transfer loop, a power

  16. Surface morphology analysis of dental implants following insertion into bone using scanning electron microscopy: a pilot study.

    PubMed

    Deppe, Herbert; Grünberg, Christina; Thomas, Mücke; Sculean, Anton; Benner, Klaus-Ulrich; Bauer, Florian J M

    2015-11-01

    Dental implants have become essential in reconstructive dentistry. Primary healing is determined by the design of their surface. The aim of this pilot study has been to investigate whether the morphology of the sandblasted and acid-etched (SLA(®) ) surface remains unaffected after the insertion process into human bone. Two edentulous-atrophied human jaw specimens were used. Six brand new Straumann Standard RN implants with an SLA(®) surface and having a diameter of 3.3 mm and a length of 12 mm were inserted. Another two implants of the same type, but not inserted into bone, served as a reference. After explantation, the four implants were cleaned in an ultrasonic bath and two were left uncleaned. All eight implants were inspected by SEM for qualitative surface changes. All four implants showed relevant changes of the topography at the apical thread flanks. The non-cleaned implants showed an almost complete coverage of the surface by a honeycomb-like structure, consistent with bone residues. The reference implants showed no changes. The results indicate that, for the osseointegration of dental implants, subtractive modifications of implant surfaces are less important than the reestablishment of the destroyed TiO2 layer. Further studies of other implant surfaces are required to verify the present results. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  17. Study of surface exfoliation on 6H-SiC induced by H2+ implantation

    NASA Astrophysics Data System (ADS)

    Zhang, L.; Li, B. S.

    2017-03-01

    The effect of lattice damage generated by the H2+-implantation on exfoliation efficiency in 6H-SiC wafers is investigated. <0001> 6H-SiC wafers were implanted with 134 keV H2+ ions to ion fluences from 1.5×1016 to 5×1016 H2+ cm-2 and subsequently annealed at temperatures from 973 K to 1373 K. The samples were studied by a combination of optical microscopy and transmission electron microscopy. Only after 1373 K annealing for 15 min, blisters and exfoliation occur on the H2+-implanted sample surface. With increasing the implantation fluences from 1.5×1016 to 3.75×1016 H2+ cm-2, the exfoliation mean size decreases, while the exfoliation density increases. For the highest fluence of 5×1016 H2+ cm-2, seldom exfoliations occur on the sample surface. Microstructure analysis shows that exfoliation efficiency is largely controlled by the H2+-implantation-induced lattice damage. The depth of the microcrack is related to the implantation fluence. The effect of implantation fluence on dislocation loops, platelet nucleation and growth is investigated.

  18. Surface-mediated bone tissue morphogenesis from tunable nanolayered implant coatings*

    PubMed Central

    Shah, Nisarg J.; Hyder, Md. Nasim; Moskowitz, Joshua S.; Quadir, Mohiuddin A.; Morton, Stephen W.; Seeherman, Howard J.; Padera, Robert F.; Spector, Myron; Hammond, Paula T.

    2014-01-01

    The functional success of a biomedical implant critically depends on its stable bonding with the host tissue. Aseptic implant loosening accounts for over half of all joint replacement failures. Various materials, including metals and plastic, confer mechanical integrity to the device, but often these materials are not suitable for direct integration with the host tissue, which leads to implant loosening and patient morbidity. We describe a self-assembled, osteogenic, polymer-based conformal coating that promotes stable mechanical fixation of an implant in a surrogate rodent model. A single modular, polymer-based multilayered coating was deposited using a water-based layer-by-layer approach, by which each element was introduced on the surface in nanoscale layers. Osteoconductive hydroxyapatite (HAP) and osteoinductive bone morphogenetic protein 2 (BMP-2) contained within the nanostructured coating acted synergistically to induce osteoblastic differentiation of endogenous progenitor cells within the bone marrow, without indications of a foreign body response. The tuned release of BMP-2, controlled by a hydrolytically degradable poly(β-amino ester), was essential for tissue regeneration and, in the presence of HAP, the modular coating encouraged the direct deposition of highly cohesive trabecular bone on the implant surface. The bone-implant interfacial tensile strength was significantly higher than standard bone cement, did not fracture at the interface, and had long-term stability. Collectively, these results suggest that the multilayered coating system promotes biological fixation of orthopedic and dental implants to improve surgical outcomes by preventing loosening and premature failure. PMID:23803705

  19. Ion implantation into collagen-coated surfaces for the development of small diameter artificial grafts.

    PubMed

    Kurotobi; Kaibara; Suzuki; Iwaki; Nakajima; Kaneko

    2000-12-30

    Ion implantation into collagen (Type I) coated inner surfaces of test tubes with a length of 50 mm and an inner diameter of 2 and 3 mm were performed to develop hybrid type small diameter artificial vascular grafts. To obtain information about the cellular response and chemical and physical structure of those collagen surfaces, several experiments such as platelets adhesion test, endothelial cell culture, analysis of amino acids and animal study were performed. He(+) ion implanted collagen coated specimen exhibited cell attachment and inhibit platelet adhesion. From these results, it was assumed that He(+) ions broke the ligands that correspond to platelet, and the ligands that correspond to endothelial cell adhesion still existed after ion implantation. It was suggested that platelets and cell attachment could be control individually by ion implantation into collagen.

  20. Use of Er:YAG laser to decontaminate infected dental implant surface in preparation for reestablishment of bone-to-implant contact.

    PubMed

    Nevins, Myron; Nevins, Marc L; Yamamoto, Atsuhiko; Yoshino, Toshiaki; Ono, Yoshihiro; Wang, Chin-Wei; Kim, David M

    2014-01-01

    The prevalence of peri-implantitis is of concern to all clinicians participating in implant dentistry. Peri-implant inflammation results in the loss of supporting bone for the implant that may or may not be accompanied by bleeding on probing and suppuration. Early diagnosis and intervention are mandated, but there is a paucity of evidence leading to the most effective therapy. There is agreement that one of the challenges in surgically treating peri-implant defects is the process of cleaning and decontaminating the implant surface, which may be contaminated by bacterial aggregates. This preclinical canine study investigates the erbium:yttrium-aluminum-garnet laser to decontaminate the complex rough surface of the implant by stripping the contaminated oxide layer for induction of hard and soft tissue adaptation to a compromised or failing implant. The results provide evidence of new bone-to-implant contact established at a level representative of the size of the defects. The soft tissues contain little or no evidence of inflammation, which can be interpreted as an arrest of the disease progression process. The results can be translated to a treatment goal of stabilizing the prognosis of an implant that has been compromised.

  1. Analysis of ion-implanted surface and interface structures by computer-simulated backscattering spectra

    NASA Astrophysics Data System (ADS)

    Kido, Y.; Kakeno, M.; Yamada, K.; Kawamoto, J.; Ohsawa, H.

    1985-10-01

    Computer codes for synthesizing random and channeling backscattering spectra have been elaborated to characterize the surface and interface structures formed or modified by ion implantation. Both effects of isotopes and energy fluctuation are taken into account in the spectrum simulation. This backscattering measurement combined with the simulation method is applied to characterization of the N(+)-implanted Al films and to quantitative analysis of chemical reaction and interdiffusion induced by ion-beam mixing. An ion-beam-induced damage profile and its epitaxial recovery of crystallinity are analyzed by the simulation of channeling spectra from ion-implanted Al2O3 substrates.

  2. Investigation of the surface of implanted silicon crystal by the contact angle

    SciTech Connect

    Lebedeva, N.N.; Bakovets, V.V.; Sedymova, E.A.; Pridachin, N.B.

    1987-03-01

    The authors study the dependence of the critical contact angle of silicon upon the dose of its irradiation by argon and boron ions. It is established that the system of immiscible liquids ether-water can be successfully used to study the influence of ion implantation of silicon on its wettability by water. The change in the wettability of implanted silicon is related to the increase in the level of the defect state of the layer surface. Wetting of implanted silicon by melts at high temperatures can be used for studying the kinetics and the annealing mechanism of defects.

  3. Corrosion behavior of surface films on boron-implanted high purity iron and stainless steels

    NASA Technical Reports Server (NTRS)

    Kim, H. J.; Carter, W. B.; Hochman, R. F.; Meletis, E. I.

    1985-01-01

    Boron (dose, 2 x 10 to the 17th ions/sq cm) was implanted into high purity iron, AISI 316 austenitic stainless steel, and AISI 440C martensitic stainless steel, at 40 keV. The film structure of implanted samples was examined and characterized by contrast and diffraction analyses utilizing transmission electron microscopy. The effect of B(+) ion implantation on the corrosion behavior was studied using the potentiodynamic polarization technique. Tests were performed in deaerated 1 N H2SO4 and 0.1 M NaCl solutions. Scanning electron microscopy was used to examine the morphology of the corroded surfaces after testing.

  4. Corrosion behavior of surface films on boron-implanted high purity iron and stainless steels

    NASA Technical Reports Server (NTRS)

    Kim, H. J.; Carter, W. B.; Hochman, R. F.; Meletis, E. I.

    1985-01-01

    Boron (dose, 2 x 10 to the 17th ions/sq cm) was implanted into high purity iron, AISI 316 austenitic stainless steel, and AISI 440C martensitic stainless steel, at 40 keV. The film structure of implanted samples was examined and characterized by contrast and diffraction analyses utilizing transmission electron microscopy. The effect of B(+) ion implantation on the corrosion behavior was studied using the potentiodynamic polarization technique. Tests were performed in deaerated 1 N H2SO4 and 0.1 M NaCl solutions. Scanning electron microscopy was used to examine the morphology of the corroded surfaces after testing.

  5. Penile prosthesis implant: scientific advances and technological innovations over the last four decades.

    PubMed

    Chung, Eric

    2017-02-01

    Despite introduction of oral phosphodiesterase type 5 inhibitors and intracavernosal vasoactive agents, penile prosthesis implant remains a relevant and desired option with sales of penile prostheses continue to stay high, as many men became refractory to medical therapy and/or seeking a more effective and permanent therapy. There are two types of penile prosthesis implants: inflatable and non-inflatable types, and the inflatable penile implants can be subdivided into single-, two- and three-piece devices. Non-inflatable penile prosthesis (non-IPP) may be referred to as semi-rigid rod or malleable prosthesis. IPP is considered a superior option to malleable prosthesis as it produces penile rigidity and flaccidity that closely replicates a normal penile erectile function. Since the introduction of IPP by Scott in 1973, surgical landscape for penile prosthesis implantation has changed dramatically. Advances in prosthesis design, device technologies and surgical techniques have made penile prosthesis implant a more natural, durable and reliable device. The following article reviews the scientific advances and technological innovation in modern penile prosthesis implants over the last four decades.

  6. Penile prosthesis implant: scientific advances and technological innovations over the last four decades

    PubMed Central

    2017-01-01

    Despite introduction of oral phosphodiesterase type 5 inhibitors and intracavernosal vasoactive agents, penile prosthesis implant remains a relevant and desired option with sales of penile prostheses continue to stay high, as many men became refractory to medical therapy and/or seeking a more effective and permanent therapy. There are two types of penile prosthesis implants: inflatable and non-inflatable types, and the inflatable penile implants can be subdivided into single-, two- and three-piece devices. Non-inflatable penile prosthesis (non-IPP) may be referred to as semi-rigid rod or malleable prosthesis. IPP is considered a superior option to malleable prosthesis as it produces penile rigidity and flaccidity that closely replicates a normal penile erectile function. Since the introduction of IPP by Scott in 1973, surgical landscape for penile prosthesis implantation has changed dramatically. Advances in prosthesis design, device technologies and surgical techniques have made penile prosthesis implant a more natural, durable and reliable device. The following article reviews the scientific advances and technological innovation in modern penile prosthesis implants over the last four decades. PMID:28217449

  7. Microstructures of Si surface layers implanted with Cu

    NASA Astrophysics Data System (ADS)

    Follstaedt, D. M.; Myers, S. M.

    Microstructures of Si ion-implanted with Cu have been characterized by TEM after annealing. For 1.2 at.%, the Cu is trapped at planar defects, but for 10 at.%, (eta)-Cu3Si forms and Cu diffuses at its equilibrium solubility. These observations allow proper evaluation of the binding energies of Cu to previously formed internal cavities (2.2 eV) and (eta)-Cu3Si (1.7 eV). The 10 at.% Cu layer promotes oxidation of Si catalyzed by (eta)-Cu3Si. The microstructures also indicate that Si implanted with (approximately)2 at.% Cu reforms epitaxially with embedded defects after 8 hr at 700C, but for (approximately)10 at.% Cu, epitaxy is not recovered after 6 hours at 600C.

  8. Microstructures of Si surface layers implanted with Cu

    SciTech Connect

    Follstaedt, D.M.; Myers, S.M.

    1993-12-31

    Microstructures of Si ion-implanted with Cu have been characterized by TEM after annealing. For 1.2 at.%, the Cu is trapped at planar defects, but for 10 at.%, {eta}-Cu{sub 3}Si forms and Cu diffuses at its equilibrium solubility. These observations allow proper evaluation of the binding energies of Cu to previously formed internal cavities (2.2 eV) and {eta}-Cu{sub 3}Si (1.7 eV). The 10 at.% Cu layer promotes oxidation of Si catalyzed by {eta}-Cu{sub 3}Si. The microstructures also indicate that Si implanted with {approximately}2 at.% Cu reforms epitaxially with embedded defects after 8 hr at 700C, but for {approximately}10 at.% Cu, epitaxy is not recovered after 6 hours at 600C.

  9. Surface and interface modification science and technology.

    SciTech Connect

    Park, J.-H.

    1999-07-19

    Surface modification of solids is of scientific and technological interest due to its significant benefits in a wide variety of applications. Various coatings applications such as corrosion protection and electrical insulators and conductors are required for proper engineering design based on geometrical relationships between interfaces and on thermodynamic/kinetic considerations for the development of surface modifications. This paper will explore three basic examples: the proton conductor BaCeO{sub 3}, high-temperature protective coatings, and epitaxial relationships between interfaces.

  10. Biological response on a titanium implant-grade surface functionalized with modular peptides☆

    PubMed Central

    Yazici, H.; Fong, H.; Wilson, B.; Oren, E.E.; Amos, F.A.; Zhang, H.; Evans, J.S.; Snead, M.L.; Sarikaya, M.; Tamerler, C.

    2015-01-01

    Titanium (Ti) and its alloys are among the most successful implantable materials for dental and orthopedic applications. The combination of excellent mechanical and corrosion resistance properties makes them highly desirable as endosseous implants that can withstand a demanding biomechanical environment. Yet, the success of the implant depends on its osteointegration, which is modulated by the biological reactions occurring at the interface of the implant. A recent development for improving biological responses on the Ti-implant surface has been the realization that bifunctional peptides can impart material binding specificity not only because of their molecular recognition of the inorganic material surface, but also through their self-assembly and ease of biological conjugation properties. To assess peptide-based functionalization on bioactivity, the present authors generated a set of peptides for implant-grade Ti, using cell surface display methods. Out of 60 unique peptides selected by this method, two of the strongest titanium binding peptides, TiBP1 and TiBP2, were further characterized for molecular structure and adsorption properties. These two peptides demonstrated unique, but similar molecular conformations different from that of a weak binder peptide, TiBP60. Adsorption measurements on a Ti surface revealed that their disassociation constants were 15-fold less than TiBP60. Their flexible and modular use in biological surface functionalization were demonstrated by conjugating them with an integrin recognizing peptide motif, RGDS. The functionalization of the Ti surface by the selected peptides significantly enhanced the bioactivity of osteoblast and fibroblast cells on implant-grade materials. PMID:23159566

  11. Science and technology of biocompatible thin films for implantable biomedical devices.

    PubMed

    Li, Wei; Kabius, Bernd; Auciello, Orlando

    2010-01-01

    This presentation focuses on reviewing research to develop two critical biocompatible film technologies to enable implantable biomedical devices, namely: 1) development of bioinert/biocompatible coatings for encapsulation of Si chips implantable in the human body (e.g., retinal prosthesis implantable in the human eye)-the coating involves a novel ultrananocrystalline diamond (UNCD) film or hybrid biocompatible oxide/UNCD layered films; and 2) development of biocompatible films with high-dielectric constant and microfabrication process to produce energy storage super-capacitors embedded in the microchip to achieve full miniaturization for implantation into the human bodynovel Al2O3/TiO2 nanolaminates exhibit abnormally high dielectric constant to enable super-capacitors with very high-capacitance.

  12. Enhancement technology and outcomes: what professionals and researchers can learn from those skeptical about cochlear implants.

    PubMed

    Kermit, Patrick

    2012-12-01

    This text presents an overview of the bioethical debate on pediatric cochlear implants and pays particular attention to the analysis of the Deaf critique of implantation. It dismisses the idea that Deaf concerns are primarily about the upholding of Deaf culture and sign language. Instead it is argued that Deaf skepticism about child rehabilitation after cochlear surgery is well founded. Many Deaf people have lived experiences as subjects undergoing rehabilitation. It is not the cochlear technology in itself they view as problematic, but rather the subsequent rehabilitation process. Because they themselves have experienced what they describe as harmful effects which relate above all to the idea of normalization, they have articulated worries for the new generations of deaf children in need of rehabilitation following cochlear implant surgery. These insights have attracted little attention, but could represent relevant ethical questions of which both practitioners and researchers in the field of implantation might be aware.

  13. Effect of implantoplasty on fracture resistance and surface roughness of standard diameter dental implants.

    PubMed

    Costa-Berenguer, Xavier; García-García, Marta; Sánchez-Torres, Alba; Sanz-Alonso, Mariano; Figueiredo, Rui; Valmaseda-Castellón, Eduard

    2017-07-23

    To assess the effect of implantoplasty on the fracture resistance, surface roughness, and macroscopic morphology of standard diameter (4.1 mm) external connection dental implants. An in vitro study was conducted in 20 screw-shaped titanium dental implants with an external connection. In 10 implants, the threads and surface were removed and polished with high-speed burs (implantoplasty), while the remaining 10 implants were used as controls. The final implant dimensions were recorded. The newly polished surface quality was assessed by scanning electron microscopy (SEM) and by 3D surface roughness analysis using a confocal laser microscope. Finally, all the implants were subjected to a mechanical pressure resistance test. A descriptive analysis of the data was made. Also, Student's t tests were employed to detect differences regarding the compression tests. Implantoplasty was carried out for a mean time of 10 min and 48 s (standard deviation (SD) of 1 min 22 s). Macroscopically, the resulting surface had a smooth appearance, although small titanium shavings and silicon debris were present. The final surface roughness (Sa values 0.1 ± 0.02 μm) was significantly lower than that of the original (0.75 ± 0.08 μm Sa ) (p = .005). There was minimal reduction in the implant's inner body diameter (0.19 ± 0.03 mm), and no statistically significant differences were found between the test and control implants regarding the maximum resistance force (896 vs 880 N, respectively). Implantoplasty, although technically demanding and time-consuming, does not seem to significantly alter fracture resistance of standard diameter external connection implants. A smooth surface with Sa values below 0.1 μm can be obtained through the use of silicon polishers. A larger sample is required to confirm that implantoplasty does not significantly affect the maximum resistance force of standard diameter external connection implants. © 2017 John Wiley & Sons A/S. Published by

  14. Retardation of surface corrosion of biodegradable magnesium-based materials by aluminum ion implantation

    NASA Astrophysics Data System (ADS)

    Wu, Guosong; Xu, Ruizhen; Feng, Kai; Wu, Shuilin; Wu, Zhengwei; Sun, Guangyong; Zheng, Gang; Li, Guangyao; Chu, Paul K.

    2012-07-01

    Aluminum ion implantation is employed to modify pure Mg as well as AZ31 and AZ91 magnesium alloys and their surface degradation behavior in simulated body fluids is studied. Polarization tests performed in conjunction with scanning electron microscopy (SEM) reveal that the surface corrosion resistance after Al ion implantation is improved appreciably. This enhancement can be attributed to the formation of a gradient surface structure with a gradual transition from an Al-rich oxide layer to Al-rich metal layer. Compared to the high Al-content magnesium alloy (AZ91), a larger reduction in the degradation rate is achieved from pure magnesium and AZ31. Our results reveal that the surface corrosion resistance of Mg alloys with no or low Al content can be improved by Al ion implantation.

  15. Simultaneous Sterilization With Surface Modification Of Plastic Bottle By Plasma-Based Ion Implantation

    SciTech Connect

    Sakudo, N.; Ikenaga, N.; Ikeda, F.; Nakayama, Y.; Kishi, Y.; Yajima, Z.

    2011-01-07

    Dry sterilization of polymeric material is developed. The technique utilizes the plasma-based ion implantation which is same as for surface modification of polymers. Experimental data for sterilization are obtained by using spores of Bacillus subtilis as samples. On the other hand we previously showed that the surface modification enhanced the gas barrier characteristics of plastic bottles. Comparing the implantation conditions for the sterilization experiment with those for the surface modification, we find that both sterilization and surface modification are simultaneously performed in a certain range of implantation conditions. This implies that the present bottling system for plastic vessels will be simplified and streamlined by excluding the toxic peroxide water that has been used in the traditional sterilization processes.

  16. Simultaneous Sterilization With Surface Modification Of Plastic Bottle By Plasma-Based Ion Implantation

    NASA Astrophysics Data System (ADS)

    Sakudo, N.; Ikenaga, N.; Ikeda, F.; Nakayama, Y.; Kishi, Y.; Yajima, Z.

    2011-01-01

    Dry sterilization of polymeric material is developed. The technique utilizes the plasma-based ion implantation which is same as for surface modification of polymers. Experimental data for sterilization are obtained by using spores of Bacillus subtilis as samples. On the other hand we previously showed that the surface modification enhanced the gas barrier characteristics of plastic bottles. Comparing the implantation conditions for the sterilization experiment with those for the surface modification, we find that both sterilization and surface modification are simultaneously performed in a certain range of implantation conditions. This implies that the present bottling system for plastic vessels will be simplified and streamlined by excluding the toxic peroxide water that has been used in the traditional sterilization processes.

  17. Nanostructure of NiTi surface layers after Ta ion implantation

    NASA Astrophysics Data System (ADS)

    Girsova, S. L.; Poletika, T. M.; Meisner, L. L.; Schmidt, E. Yu.

    2016-11-01

    The elemental and phase composition and structure of the surface and near-surface layers of NiTi specimens after the Ta ion implantation with the fluency D = 3 × 1017 and 6 × 1017 cm-2 are examined. The methods of Auger electron spectroscopy (AES), transmission electron microscopy (TEM), and electron dispersion analysis (EDS) are used. It is found that a nonuniform distribution of elements along the depth of the surface layer after the ion implantation of NiTi specimens, regardless of the regime, is accompanied by the formation of a number of sublayer structures.

  18. Plasma immersion ion implantation for surface treatment of complex branched structures

    NASA Astrophysics Data System (ADS)

    Kashin, Oleg A.; Lotkov, Alexander I.; Borisov, Dmitry P.; Slabodchikov, Vladimir A.; Kuznetsov, Vladimir M.; Kudryashov, Andrey N.; Krukovsky, Konstantin V.

    2016-11-01

    The paper presents experimental results demonstrating the capabilities of plasma immersion ion implantation of silicon (Si) for surface treatment of complex branched structures such are self-expanding intravascular nickel-titanium (NiTi) stents. Using NiTi stents of diameter 4 and 8 mm, it is shown that plasma immersion ion implantation can provide rather homogeneous doping of their outer and inner surfaces with Si atoms. Also presented are research data on the processes that determine the thickness, composition, and structure of surface layers subjected to this type of treatment.

  19. Heat Generation on Implant Surface During Abutment Preparation at Different Elapsed Time Intervals.

    PubMed

    Al-Keraidis, Abdullah; Aleisa, Khalil; Al-Dwairi, Ziad Nawaf; Al-Tahawi, Hamdi; Hsu, Ming-Lun; Lynch, Edward; Özcan, Mutlu

    2017-10-01

    The purpose of this study was to evaluate heat generation at the implant surface caused by abutment preparation using a diamond bur in a high-speed dental turbine in vitro at 2 different water-coolant temperatures. Thirty-two titanium-alloy abutments were connected to a titanium-alloy implant embedded in an acrylic resin placed within a water bath at a controlled temperature of 37°C. The specimens were equally distributed into 2 groups (16 each). Group 1: the temperature was maintained at 20 ± 1°C; and group 2: the temperature was maintained at 32 ± 1°C. Each abutment was prepared in the axial plane for 1 minute and in the occlusal plane for 1 minute. The temperature of the heat generated from abutment preparation was recorded and measured at 3 distinct time intervals. Water-coolant temperature (20°C vs 32°C) had a statistically significant effect on the implant's temperature change during preparation of the abutment (P < 0.0001). The use of water-coolant temperature of 20 ± 1°C during preparation of the implant abutment decreased the temperature recorded at the implant surface to 34.46°C, whereas the coolant temperature of 32 ± 1°C increased the implant surface temperature to 40.94°C.

  20. Evolution and acceptability of medical applications of RFID implants among early users of technology.

    PubMed

    Smith, Alan D

    2007-01-01

    RFID as a wireless identification technology that may be combined with microchip implants have tremendous potential in today's market. Although these implants have their advantages and disadvantages, recent improvements how allowed for implants designed for humans. Focus was given to the use of RFID tags and its effects on technology and CRM through a case study on VeriChip, the only corporation to hold the rights and the patent to the implantable chip for humans, and an empirically based study on working professionals to measure perceptions by early adopters of such technology. Through hypotheses-testing procedures, it was found that although some resistance to accept microchip implants was found in several applications, especially among gender, it was totally expected that healthcare and medical record keeping activities would be universally treated in a positive light and the use of authorities (namely governmental agencies) would be equally treated in a negative light by both sexes. Future trends and recommendations are presented along with statistical results collected through personal interviews.

  1. Controlled removal of ceramic surfaces with combination of ions implantation and ultrasonic energy

    DOEpatents

    Boatner, Lynn A.; Rankin, Janet; Thevenard, Paul; Romana, Laurence J.

    1995-01-01

    A method for tailoring or patterning the surface of ceramic articles is provided by implanting ions to predetermined depth into the ceramic material at a selected surface location with the ions being implanted at a fluence and energy adequate to damage the lattice structure of the ceramic material for bi-axially straining near-surface regions of the ceramic material to the predetermined depth. The resulting metastable near-surface regions of the ceramic material are then contacted with energy pulses from collapsing, ultrasonically-generated cavitation bubbles in a liquid medium for removing to a selected depth the ion-damaged near-surface regions containing the bi-axially strained lattice structure from the ceramic body. Additional patterning of the selected surface location on the ceramic body is provided by implanting a high fluence of high-energy, relatively-light ions at selected surface sites for relaxing the bi-axial strain in the near-surface regions defined by these sites and thereby preventing the removal of such ion-implanted sites by the energy pulses from the collapsing ultrasonic cavitation bubbles.

  2. Surface transport vehicles and supporting technology requirements

    NASA Technical Reports Server (NTRS)

    Matijevic, J. R.; Dias, W. C.; Levin, R. R.; Lindemann, R. A.; Smith, J. H.; Venkataraman, S. T.

    1992-01-01

    Requirements have been identified for surface transport vehicles which allow remote scientific exploration on the moon, as well as lunar resource recovery and emplacement of a permanent base on the lunar surface. Attention is given to the results of a design study which developed configurational concepts for lunar surface transport vehicles and inferred technology-development requirements, with a view to a phased program of implementation. Distinct benefits are noted for the design of simple vehicle platforms with high commonality, in order to reduce logistical-support requirements and maximize functional flexibility. Two generic vehicle classed are defined.

  3. Laser-Modified Surface Enhances Osseointegration and Biomechanical Anchorage of Commercially Pure Titanium Implants for Bone-Anchored Hearing Systems

    PubMed Central

    Omar, Omar; Simonsson, Hanna; Palmquist, Anders; Thomsen, Peter

    2016-01-01

    Osseointegrated implants inserted in the temporal bone are a vital component of bone-anchored hearing systems (BAHS). Despite low implant failure levels, early loading protocols and simplified procedures necessitate the application of implants which promote bone formation, bone bonding and biomechanical stability. Here, screw-shaped, commercially pure titanium implants were selectively laser ablated within the thread valley using an Nd:YAG laser to produce a microtopography with a superimposed nanotexture and a thickened surface oxide layer. State-of-the-art machined implants served as controls. After eight weeks’ implantation in rabbit tibiae, resonance frequency analysis (RFA) values increased from insertion to retrieval for both implant types, while removal torque (RTQ) measurements showed 153% higher biomechanical anchorage of the laser-modified implants. Comparably high bone area (BA) and bone-implant contact (BIC) were recorded for both implant types but with distinctly different failure patterns following biomechanical testing. Fracture lines appeared within the bone ~30–50 μm from the laser-modified surface, while separation occurred at the bone-implant interface for the machined surface. Strong correlations were found between RTQ and BIC and between RFA at retrieval and BA. In the endosteal threads, where all the bone had formed de novo, the extracellular matrix composition, the mineralised bone area and osteocyte densities were comparable for the two types of implant. Using resin cast etching, osteocyte canaliculi were observed directly approaching the laser-modified implant surface. Transmission electron microscopy showed canaliculi in close proximity to the laser-modified surface, in addition to a highly ordered arrangement of collagen fibrils aligned parallel to the implant surface contour. It is concluded that the physico-chemical surface properties of laser-modified surfaces (thicker oxide, micro- and nanoscale texture) promote bone bonding

  4. Laser-Modified Surface Enhances Osseointegration and Biomechanical Anchorage of Commercially Pure Titanium Implants for Bone-Anchored Hearing Systems.

    PubMed

    Shah, Furqan A; Johansson, Martin L; Omar, Omar; Simonsson, Hanna; Palmquist, Anders; Thomsen, Peter

    2016-01-01

    Osseointegrated implants inserted in the temporal bone are a vital component of bone-anchored hearing systems (BAHS). Despite low implant failure levels, early loading protocols and simplified procedures necessitate the application of implants which promote bone formation, bone bonding and biomechanical stability. Here, screw-shaped, commercially pure titanium implants were selectively laser ablated within the thread valley using an Nd:YAG laser to produce a microtopography with a superimposed nanotexture and a thickened surface oxide layer. State-of-the-art machined implants served as controls. After eight weeks' implantation in rabbit tibiae, resonance frequency analysis (RFA) values increased from insertion to retrieval for both implant types, while removal torque (RTQ) measurements showed 153% higher biomechanical anchorage of the laser-modified implants. Comparably high bone area (BA) and bone-implant contact (BIC) were recorded for both implant types but with distinctly different failure patterns following biomechanical testing. Fracture lines appeared within the bone ~30-50 μm from the laser-modified surface, while separation occurred at the bone-implant interface for the machined surface. Strong correlations were found between RTQ and BIC and between RFA at retrieval and BA. In the endosteal threads, where all the bone had formed de novo, the extracellular matrix composition, the mineralised bone area and osteocyte densities were comparable for the two types of implant. Using resin cast etching, osteocyte canaliculi were observed directly approaching the laser-modified implant surface. Transmission electron microscopy showed canaliculi in close proximity to the laser-modified surface, in addition to a highly ordered arrangement of collagen fibrils aligned parallel to the implant surface contour. It is concluded that the physico-chemical surface properties of laser-modified surfaces (thicker oxide, micro- and nanoscale texture) promote bone bonding which

  5. Surface engineering of a Zr-based bulk metallic glass with low energy Ar- or Ca-ion implantation.

    PubMed

    Huang, Lu; Zhu, Chao; Muntele, Claudiu I; Zhang, Tao; Liaw, Peter K; He, Wei

    2015-02-01

    In the present study, low energy ion implantation was employed to engineer the surface of a Zr-based bulk metallic glass (BMG), aiming at improving the biocompatibility and imparting bioactivity to the surface. Ca- or Ar-ions were implanted at 10 or 50 keV at a fluence of 8 × 10(15)ions/cm(2) to (Zr0.55Al0.10Ni0.05Cu0.30)99Y1 (at.%) BMG. The effects of ion implantation on material properties and subsequent cellular responses were investigated. Both Ar- and Ca-ion implantations were suggested to induce atom displacements on the surfaces according to the Monte-Carlo simulation. The change of atomic environment of Zr in the surface regions as implied by the alteration in X-ray absorption measurements at Zr K-edge. X-ray photoelectron spectroscopy revealed that the ion implantation process has modified the surface chemical compositions and indicated the presence of Ca after Ca-ion implantation. The surface nanohardness has been enhanced by implantation of either ion species, with Ca-ion implantation showing more prominent effect. The BMG surfaces were altered to be more hydrophobic after ion implantation, which can be attributed to the reduced amount of hydroxyl groups on the implanted surfaces. Higher numbers of adherent cells were found on Ar- and Ca-ion implanted samples, while more pronounced cell adhesion was observed on Ca-ion implanted substrates. The low energy ion implantation resulted in concurrent modifications in atomic structure, nanohardness, surface chemistry, hydrophobicity, and cell behavior on the surface of the Zr-based BMG, which were proposed to be mutually correlated with each other. Published by Elsevier B.V.

  6. From acid etching treatments to tribocorrosive properties of dental implants: do some experimental results on surface treatments have an influence on the tribocorrosion behaviour of dental implants?

    NASA Astrophysics Data System (ADS)

    Geringer, Jean; Demanget, Nicolas; Pellier, Julie

    2013-10-01

    Surface treatments of dental implants aim at promoting osseointegration, i.e. the anchorage of the metallic part. Titanium-, grade II-V, based material is used as a bulk material for dental implants. For promoting the anchorage of this metallic biomaterial in human jaw, some strategies have been applied for improving the surface state, i.e. roughness, topography and coatings. A case study, experimental study, is described with the method of acid etching on titanium grade 4, CpTi. The main goal is to find the right proportion in a mixture of two acids in order to obtain the best surface state. Finally, a pure theoretical prediction is quite impossible and some experimental investigations are necessary to improve the surface state. The described acid etching is compared with some other acid etching treatments and some coatings available on dental implants. Thus, the discussion is focused on the tribocorrosion behaviour of titanium-based materials. The purpose of the coating is that the lifetime under tribocorrosion is limited. Moreover, the surgery related to the implantation has a huge impact on the stability of dental implants. Thus, the performance of dental implants depends on factors related to surgery (implantation) that are difficult to predict from the biomaterial characteristics. From the tribocorrosion point of view, i.e. during the mastication step, the titanium material is submitted to some deleterious factors that cause the performance of dental implants to decrease.

  7. Electrostatic self-assembly of multilayer copolymeric membranes on the surface of porous tantalum implants for sustained release of doxorubicin

    PubMed Central

    Guo, Xinming; Chen, Muwan; Feng, Wenzhou; Liang, Jiabi; Zhao, Huibin; Tian, Lin; Chao, Hui; Zou, Xuenong

    2011-01-01

    Many studies in recent years have focused on surface engineering of implant materials in order to improve their biocompatibility and other performance. Porous tantalum implants have increasingly been used in implant surgeries, due to their biocompatibility, physical stability, and good mechanical strength. In this study we functionalized the porous tantalum implant for sustained drug delivery capability via electrostatic self-assembly of polyelectrolytes of hyaluronic acid, methylated collagen, and terpolymer on the surface of a porous tantalum implant. The anticancer drug doxorubicin was encapsulated into the multilayer copolymer membranes on the porous tantalum implants. Results showed the sustained released of doxorubicin from the functionalized porous tantalum implants for up to 1 month. The drug release solutions in 1 month all had inhibitory effects on the proliferation of chondrosarcoma cell line SW1353. These results suggest that this functionalized implant could be used in reconstructive surgery for the treatment of bone tumor as a local, sustained drug delivery system. PMID:22162662

  8. Electrostatic self-assembly of multilayer copolymeric membranes on the surface of porous tantalum implants for sustained release of doxorubicin.

    PubMed

    Guo, Xinming; Chen, Muwan; Feng, Wenzhou; Liang, Jiabi; Zhao, Huibin; Tian, Lin; Chao, Hui; Zou, Xuenong

    2011-01-01

    Many studies in recent years have focused on surface engineering of implant materials in order to improve their biocompatibility and other performance. Porous tantalum implants have increasingly been used in implant surgeries, due to their biocompatibility, physical stability, and good mechanical strength. In this study we functionalized the porous tantalum implant for sustained drug delivery capability via electrostatic self-assembly of polyelectrolytes of hyaluronic acid, methylated collagen, and terpolymer on the surface of a porous tantalum implant. The anticancer drug doxorubicin was encapsulated into the multilayer copolymer membranes on the porous tantalum implants. Results showed the sustained released of doxorubicin from the functionalized porous tantalum implants for up to 1 month. The drug release solutions in 1 month all had inhibitory effects on the proliferation of chondrosarcoma cell line SW1353. These results suggest that this functionalized implant could be used in reconstructive surgery for the treatment of bone tumor as a local, sustained drug delivery system.

  9. Formation of Wear Resistant Steel Surfaces by Plasma Immersion Ion Implantation

    SciTech Connect

    Maendl, S.; Rauschenbach, B.

    2003-08-26

    Plasma immersion ion implantation (PIII) is a versatile and fast method for implanting energetic ions into large and complex shaped three-dimensional objects where the ions are accelerated by applying negative high voltage pulses to a substrate immersed in a plasma. As the line-of-sight restrictions of conventional implanters are circumvented, it results in a fast and cost-effective technology. Implantation of nitrogen at 30 - 40 keV at moderate temperatures of 200 - 400 deg. C into steel circumvents the diminishing thermal nitrogen activation encountered, e.g., in plasma nitriding in this temperature regime, thus enabling nitriding of additional steel grades. Nitride formation and improvement of the mechanical properties after PIII are presented for several steel grades, including AISI 316Ti (food industry), AISI D2 (used for bending tools) and AISI 1095 (with applications in the textile industry)

  10. Surface area analysis of dental implants using micro-computed tomography.

    PubMed

    Schicho, Kurt; Kastner, Johann; Klingesberger, Roman; Seemann, Rudolf; Enislidis, Georg; Undt, Gerhard; Wanschitz, Felix; Figl, Michael; Wagner, Arne; Ewers, Rolf

    2007-08-01

    In this study, we present and evaluate a micro-computed tomography (micro-CT)-based method for the calculation of the potential bone/implant contact area (p-BICA) on the surface of dental implants. For seven commercially available implants (Ankylos implant, Brånemark System, Frialit CELLplus, Replace((R)) Select Tapered, Straumann Solid screw, XiVE S CELLplus, 3i Osseotite XP Threaded Miniplant, the p-BICA surface is determined by means of three-dimensional X-ray computed-tomography and computer-based data processing. Measurements were repeated two times, and the stability and repeatability of the measurement method were evaluated. Our analysis revealed a p-BICA of 118 mm(2) for the XiVE S CELLplus implant, 134 mm(2) for the Ankylos, 136 mm(2) for the Frialit CELLplus, 138 mm(2) for the Brånemark System, 139 mm(2) for the Replace((R)), 159 mm(2) for the 3i Osseotite XP and 199 mm(2) for the Straumann Solid screw implant. The measurement method proved to be stable and led to reproducible results. The micro- and macrostructure of dental implants define the surface and the p-BICA. Precise determination of this parameter can be achieved by means of the micro-CT-based method as presented in this study. The value of p-BICA lies in the predictability of industrial design before preclinical and clinical testing. Based on this method, dental implant properties become comparable even if geometrical details are not disclosed by the manufacturer.

  11. Bone mineral apposition rates at early implantation times around differently prepared titanium surfaces: a study in beagle dogs.

    PubMed

    Coelho, Paulo G; Freire, Jose N; Granato, Rodrigo; Marin, Charles; Bonfante, Estevam A; Gil, Jose N; Chuang, Sung-Kiang; Suzuki, Marcelo

    2011-01-01

    This study evaluated the bone mineral apposition rate (MAR) at the bone-implant interface region of alumina-blasted/acid-etched (AB/AE), plasma-sprayed hydroxyapatite (PSHA), and nanometric-scale bioceramic-coated surfaces at early implantation times in a dog tibia model. Implants (n = 12 per group) with three different surfaces-AB/AE, PSHA, and a bioceramic coating in the 300- to 500-nm thickness range-were placed bilaterally along the proximal tibiae of six male beagles. Implants remained for 3 and 5 weeks in vivo. Ten and 2 days prior to euthanization, calcein green and oxytetracycline were administered for bone labeling. Following euthanization, the limbs were retrieved by sharp dissection and the implants and bone were processed nondecalcified into ~30-Μm-thick sections along the implant long axis. MAR was measured by the distance between bone labels over time at the interface region (to 0.5 mm from the implant surface) and at regions > 3 mm from the implant surface (remote site). A generalized linear mixed-effects analysis of variance model was conducted with significance levels set at .05. Irrespective of implant surface, the MAR at the interface region was significantly higher than the MAR at the remote site. Significant MAR differences in the interface region were observed between the different surfaces (PSHA > AB/AE > nano). Bone kinetics during early healing stages were influenced by implant surface modifications.

  12. The effect of plasma surface treatment on the bioactivity of titanium implant materials (in vitro)

    PubMed Central

    Abdelrahim, Ramy A.; Badr, Nadia A.; Baroudi, Kusai

    2016-01-01

    Background: The surface of an implantable biomaterial plays a very important role in determining the biocompatibility, osteoinduction, and osteointegration of implants because it is in intimate contact with the host bone and soft tissues. Objective: This study was aimed to assess the effect of plasma surface treatment on the bioactivity of titanium alloy (Ti–6Al–4V). Materials and Methods: Fifteen titanium alloy samples were used in this study. The samples were divided into three groups (with five samples in each group). Five samples were kept untreated and served as control (group A). Another five plasma samples were sprayed for nitrogen ion implantation on their surfaces (group B) and the last five samples were pre-etched with acid before plasma treatment (group C). All the investigated samples were immersed for 7 days in Hank's balanced salt solution (HBSS) which was used as a simulating body fluid (SBF) at pH 7.4 and 37°C. HBSS was renewed every 3 days. The different surfaces were characterized by X-ray diffraction (XRD), Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDXA), and Fourier Transformation Infrared Spectroscopy (FTIR). Results: Nitriding of Ti-alloy samples via plasma nitrogen ion implantation increased the bioactivity of titanium. Moreover, the surface topography affected the chemical structure of the formed apatite. Increasing the surface roughness enhanced the bioactivity of the implant material. Conclusions: Nitridation can be exploited as an effective way to promote the formation of bone-like material on the implant surface. PMID:27011927

  13. Corrosion of phosphate-enriched titanium oxide surface dental implants (TiUnite) under in vitro inflammatory and hyperglycemic conditions.

    PubMed

    Messer, Regina L W; Seta, Francesca; Mickalonis, John; Brown, Yolanda; Lewis, Jill B; Wataha, John C

    2010-02-01

    Endosseous dental implants use is increasing in patients with systemic conditions that compromise wound healing. Manufacturers recently have redesigned implants to ensure more reliable and faster osseointegration. One design strategy has been to create a porous phosphate-enriched titanium oxide (TiUnite) surface to increase surface area and enhance interactions with bone. In the current study, the corrosion properties of TiUnite implants were studied in cultures of monocytic cells and solutions simulating inflammatory and hyperglycemic conditions. Furthermore, to investigate whether placement into bone causes enough mechanical damage to alter implant corrosion properties, the enhanced surface implants as well as machined titanium implants were placed into human cadaver mandibular bone, the bone removed, and the corrosion properties measured. Implant corrosion behavior was characterized by open circuit potentials, linear polarization resistance, and electrical impedance spectroscopy. In selected samples, THP1 cells were activated with lipopolysaccharide prior to implant exposure to simulate an inflammatory environment. No significant differences in corrosion potentials were measured between the TiUnite implants and the machined titanium implants in previous studies. TiUnite implants exhibited lower corrosion rates in all simulated conditions than observed in PBS, and EIS measurements revealed two time constants which shifted with protein-containing electrolytes. In addition, the TiUnite implants displayed a significantly lower corrosion rate than the machined titanium implants after placement into bone. The current study suggests that the corrosion risk of the enhanced oxide implant is lower than its machined surface titanium implant counterpart under simulated conditions of inflammation, elevated dextrose concentrations, and after implantation into bone.

  14. A response surface model predicting the in vivo insertion behavior of micromachined neural implants

    NASA Astrophysics Data System (ADS)

    Andrei, A.; Welkenhuysen, M.; Nuttin, B.; Eberle, W.

    2012-02-01

    The mechanical damage caused by the insertion of a foreign body into living tissue is inevitable, especially when a considerable stiffness mismatch is present, as in the case of micromachined neural implants and brain tissue. However, the response surface model based on a central composite experimental design described in this study showed that for particular configurations of the implant tip angle, width, thickness or insertion speed, some of these factors could be safely increased without causing an unwanted significant force or tissue dimpling increase. The model covers chisel tip angles between 10° and 50°, implant widths within the 200-400 µm range and thicknesses between 50 and 150 µm. The insertion speed has been varied from 10 up to 100 µm s-1 to reach a final insertion depth of 6 mm. Coating the implant with parylene C proved to be beneficial in reducing the friction between the implant and the surrounding tissue. Successfully validated for a particular implant geometry, this model could be used as an insertion behavior prediction tool for the design optimization of future neural implants.

  15. Plasma immersion ion implantation for the efficient surface modification of medical materials

    SciTech Connect

    Slabodchikov, Vladimir A. Borisov, Dmitry P. Kuznetsov, Vladimir M.

    2015-10-27

    The paper reports on a new method of plasma immersion ion implantation for the surface modification of medical materials using the example of nickel-titanium (NiTi) alloys much used for manufacturing medical implants. The chemical composition and surface properties of NiTi alloys doped with silicon by conventional ion implantation and by the proposed plasma immersion method are compared. It is shown that the new plasma immersion method is more efficient than conventional ion beam treatment and provides Si implantation into NiTi surface layers through a depth of a hundred nanometers at low bias voltages (400 V) and temperatures (≤150°C) of the substrate. The research results suggest that the chemical composition and surface properties of materials required for medicine, e.g., NiTi alloys, can be successfully attained through modification by the proposed method of plasma immersion ion implantation and by other methods based on the proposed vacuum equipment without using any conventional ion beam treatment.

  16. Dental Implant Systems

    PubMed Central

    Oshida, Yoshiki; Tuna, Elif B.; Aktören, Oya; Gençay, Koray

    2010-01-01

    Among various dental materials and their successful applications, a dental implant is a good example of the integrated system of science and technology involved in multiple disciplines including surface chemistry and physics, biomechanics, from macro-scale to nano-scale manufacturing technologies and surface engineering. As many other dental materials and devices, there are crucial requirements taken upon on dental implants systems, since surface of dental implants is directly in contact with vital hard/soft tissue and is subjected to chemical as well as mechanical bio-environments. Such requirements should, at least, include biological compatibility, mechanical compatibility, and morphological compatibility to surrounding vital tissues. In this review, based on carefully selected about 500 published articles, these requirements plus MRI compatibility are firstly reviewed, followed by surface texturing methods in details. Normally dental implants are placed to lost tooth/teeth location(s) in adult patients whose skeleton and bony growth have already completed. However, there are some controversial issues for placing dental implants in growing patients. This point has been, in most of dental articles, overlooked. This review, therefore, throws a deliberate sight on this point. Concluding this review, we are proposing a novel implant system that integrates materials science and up-dated surface technology to improve dental implant systems exhibiting bio- and mechano-functionalities. PMID:20480036

  17. Optical studies of cobalt implanted rutile TiO2 (110) surfaces

    NASA Astrophysics Data System (ADS)

    Joshi, Shalik Ram; Padmanabhan, B.; Chanda, Anupama; Mishra, Indrani; Malik, V. K.; Mishra, N. C.; Kanjilal, D.; Varma, Shikha

    2016-11-01

    Present study investigates the photoabsorption properties of single crystal rutile TiO2 (110) surfaces after they have been implanted with low fluences of cobalt ions. The surfaces, after implantation, demonstrate fabrication of nanostructures and anisotropic nano-ripple patterns. Creation of oxygen vacancies (Ti3+ states), development of cobalt nano-clusters as well as band gap modifications have also been observed. Results presented here demonstrate that fabrication of self organized nanostructures, upon implantation, along with the development of oxygen vacancies and ligand field transitions of cobalt ion promote the enhancement of photo-absorbance in both UV (∼2 times) and visible (∼5 times) regimes. These investigations on nanostructured TiO2 surfaces can be important for photo-catalysis.

  18. Effect of exposure environment on surface decomposition of SiC-silver ion implantation diffusion couples

    DOE PAGES

    Gerczak, Tyler J.; Zheng, Guiqui; Field, Kevin G.; ...

    2014-10-05

    SiC is a promising material for nuclear applications and is a critical component in the construction of tristructural isotropic (TRISO) fuel. A primary issue with TRISO fuel operation is the observed release of 110m Ag from intact fuel particles. The release of Ag has prompted research efforts to directly measure the transport mechanism of Ag in bulk SiC. Recent research efforts have focused primarily on Ag ion implantation designs. The effect of the thermal exposure system on the ion implantation surface has been investigated. Results indicate the utilization of a mated sample geometry and the establishment of a static thermalmore » exposure environment is critical to maintaining an intact surface for diffusion analysis. In conclusion, the nature of the implantation surface and its potential role in Ag diffusion analysis are discussed.« less

  19. Effect of exposure environment on surface decomposition of SiC-silver ion implantation diffusion couples

    SciTech Connect

    Gerczak, Tyler J.; Zheng, Guiqui; Field, Kevin G.; Allen, Todd R.

    2014-10-05

    SiC is a promising material for nuclear applications and is a critical component in the construction of tristructural isotropic (TRISO) fuel. A primary issue with TRISO fuel operation is the observed release of 110m Ag from intact fuel particles. The release of Ag has prompted research efforts to directly measure the transport mechanism of Ag in bulk SiC. Recent research efforts have focused primarily on Ag ion implantation designs. The effect of the thermal exposure system on the ion implantation surface has been investigated. Results indicate the utilization of a mated sample geometry and the establishment of a static thermal exposure environment is critical to maintaining an intact surface for diffusion analysis. In conclusion, the nature of the implantation surface and its potential role in Ag diffusion analysis are discussed.

  20. Ion implanted integrated optics (I3O) technology for planar lightwave circuits (PLCs) fabrication

    NASA Astrophysics Data System (ADS)

    Drouard, Emmanuel; Escoubas, Ludovic; Flory, Francois; Tisserand, Stephane; Roux, Laurent

    2004-02-01

    The I3O technology based on Titanium ion implantation in silica is proposed for the fabrication of passive compact PLC devices. It is demonstrated that the guided field can be easily tailored to fit standard fibers or can be compatible with the use of bent waveguides having a small radius of curvature.

  1. Surface anatomy for implantation of external ventricular drainage: Some surgical remarks

    PubMed Central

    Mostofi, Kevyan; Khouzani, Reza K.

    2016-01-01

    Background: External ventricular drainage (EVD) is an emergency process intended to reduce intracranial hypertension resulting from the obstruction of cerebrospinal fluid (CSF) flow. This creates a temporary situation to extract CSF that cannot pass through normally. Knowing the surface anatomy for EVD implantation is important to prevent its inadvertent complications. The external landmarks have been designed in this anatomic study to review the classical landmarks and come up with new landmarks to improve this simple but lifesaving procedure. Methods: From November 1998 to October 2012, we implanted 439 EVDs. Results: In the first years, we employed usual landmarks to implant 97 EVDs. Since 2002, we used modified anatomical landmarks to implant 342 EVDs directly in the third ventricle. Conclusion: Using effective landmarks for EVD implementation allows the catheter to be inserted in the third ventricle. In addition, it permits more precise accuracy to ensure a safer procedure with fewer complications. PMID:27625894

  2. Surface contamination analysis technology team overview

    NASA Astrophysics Data System (ADS)

    Burns, H. Dewitt, Jr.

    1996-11-01

    The surface contamination analysis technology (SCAT) team was originated as a working roup of NASA civil service, Space Shuttle contractor, and university groups. Participating members of the SCAT Team have included personnel from NASA Marshall Space Flight Center's Materials and Processes Laboratory and Langley Research Center's Instrument Development Group; contractors-Thiokol Corporation's Inspection Technology Group, AC Engineering support contractor, Aerojet, SAIC, and Lockheed MArtin/Oak Ridge Y-12 support contractor and Shuttle External Tank prime contractor; and the University of Alabama in Huntsville's Center for Robotics and Automation. The goal of the SCAT team as originally defined was to develop and integrate a multi-purpose inspection head for robotic application to in-process inspection of contamination sensitive surfaces. One area of interest was replacement of ozone depleting solvents currently used for surface cleanliness verification. The team approach brought together the appropriate personnel to determine what surface inspection techniques were applicable to multi-program surface cleanliness inspection. Major substrates of interest were chosen to simulate space shuttle critical bonding surface or surfaces sensitive to contamination such as fuel system component surfaces. Inspection techniques evaluated include optically stimulated electron emission or photoelectron emission; Fourier transform infrared spectroscopy; near infrared fiber optic spectroscopy; and, ultraviolet fluorescence. Current plans are to demonstrate an integrated system in MSFC's Productivity Enhancement Complex within five years from initiation of this effort in 1992. Instrumentation specifications and designs developed under this effort include a portable diffuse reflectance FTIR system built by Surface Optics Corporation and a third generation optically stimulated electron emission system built by LaRC. This paper will discuss the evaluation of the various techniques on a

  3. Contacting the brain--aspects of a technology assessment of neural implants.

    PubMed

    Decker, Michael; Fleischer, Torsten

    2008-12-01

    The public interest in neural implants has grown considerably in recent years. Progress within related research areas in combination with increasing--albeit overly optimistic and indiscriminate--mass media coverage have led to the impression that the possibilities of neural prosthetics have grown enormously. But a closer look reveals that the reasons for the intensified interest are varied and cannot be attributed to technical progress alone. Some neural prostheses that have been under development for many years have not left the clinical development phase despite intensive research activities. Other implants, like cardiac pacemakers and cochlea implants, are mature products that have already been implanted in a large number of patients. From the public perspective and in media reports, progress in the development of neural implants is associated with new achievements in other fields of neuroscience. Communications on new applications of functional magnetic resonance imaging (fMRI) may suggest that a number of cognitive functions are now easily accessible with technological means. The fact that the interpretation of the results of fMRI studies depends on many conditions and is partly disputed also within the scientific community has been discussed in many publications but only very limited, in the general media. Besides this, research results and implementations in the area of electroencephalography and magnetoencephalography have sparked further debate on the question of free will, on determinism and indeterminism, and have attracted a large media response. The purpose of this paper is to discuss some societal and ethical aspects of neural implants from a technology assessment perspective. Technology assessment (TA) aims at providing knowledge about impacts and consequences of (new) technologies as well as about political and societal ways of dealing with them. It reflects about implementation conditions of technology and potential technology conflicts. Over the

  4. Effect of surface treatment on stress distribution in immediately loaded dental implants--a 3D finite element analysis.

    PubMed

    Bahrami, Babak; Shahrbaf, Shirin; Mirzakouchaki, Behnam; Ghalichi, Farzan; Ashtiani, Mohammed; Martin, Nicolas

    2014-04-01

    To investigate, by means of FE analysis, the effect of surface roughness treatments on the distribution of stresses at the bone-implant interface in immediately loaded mandibular implants. An accurate, high resolution, digital replica model of bone structure (cortical and trabecular components) supporting an implant was created using CT scan data and image processing software (Mimics 13.1; Materialize, Leuven, Belgium). An anatomically accurate 3D model of a mandibular-implant complex was created using a professional 3D-CAD modeller (SolidWorks, DassaultSystèmes Solid Works Corp; 2011). Finite element models were created with one of the four roughness treatments on the implant fixture surface. Of these, three were surface treated to create a uniform coating determined by the coefficient of friction (μ); these were either (1) plasma sprayed or porous-beaded (μ=1.0), (2) sandblasted (μ=0.68) or (3) polished (μ=0.4). The fourth implant had a novel two-part surface roughness consisting of a coronal polished component (μ=0.4) interfacing with the cortical bone, and a body plasma treated surface component (μ=1) interfacing with the trabecular bone. Finite element stress analysis was carried out under vertical and lateral forces. This investigation showed that the type of surface treatment on the implant fixture affects the stress at the bone-implant interface of an immediately loaded implant complex. Von Mises stress data showed that the two-part surface treatment created the better stress distribution at the implant-bone interface. The results from this FE computational analysis suggest that the proposed two-part surface treatment for IL implants creates lower stresses than single uniform treatments at the bone-implant interface, which might decrease peri-implant bone loss. Future investigations should focus on mechanical and clinical validation of these FE results. Copyright © 2014 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  5. Comparison between bioactive fluoride modified and bioinert anodically oxidized implant surfaces in early bone response using rabbit tibia model.

    PubMed

    Choi, Jung-Yoo; Lee, Hyo-Jung; Jang, Jae-Up; Yeo, In-Sung

    2012-04-01

    The aim of this study was to investigate whether bioactive surfaces were more favorable to bone than bioinert surfaces by evaluating bone responses around two commercial dental implants. Bioactive fluoride-modified implants (Osseospeed) were compared with bioinert oxidized implants (TiUnite). Field emission scanning electron microscopy, energy dispersive spectroscopy, and confocal laser scanning microscopy analyzed the implant surface characteristics. Five New Zealand white rabbits were used to evaluate the bone response. Each rabbit received two implants: a fluoride-modified implant in one tibia and an oxidized implant in the other. Drilling was performed bicortically, and a gap defect was created in the upper cortexonly. Bone-to-implant contact and bone area were measured on the histological specimens 2 weeks after implant insertion. No significant differences were found in surface roughness (P > 0.05). The gap defects were almost filled with new bone within a period of 2 weeks. The histomorphometry revealed no significant differences in bone-to-implant contact and bone area (P > 0.05). Within the limitation of this study, the bioactive fluoride-modified surface may show no superiority to the bioinert anodized surface in early bone response.

  6. Three-species biofilm model onto plasma-treated titanium implant surface.

    PubMed

    Matos, Adaias O; Ricomini-Filho, Antônio P; Beline, Thamara; Ogawa, Erika S; Costa-Oliveira, Bárbara E; de Almeida, Amanda B; Nociti Junior, Francisco H; Rangel, Elidiane C; da Cruz, Nilson C; Sukotjo, Cortino; Mathew, Mathew T; Barão, Valentim A R

    2017-04-01

    promising technology to treat bone-integrated dental implants as the new surfaces displayed improved mechanical and biological properties with no increase in biofilm proliferation.

  7. Comparison of surface characteristics of retrieved cobalt-chromium femoral heads with and without ion implantation.

    PubMed

    McGrory, Brian J; Ruterbories, James M; Pawar, Vivek D; Thomas, Reginald K; Salehi, Abraham B

    2012-01-01

    Nitrogen ion implantation of CoCr is reported to produce increased surface hardness and a lower friction surface. Femoral heads with and without ion implantation retrieved from 1997 to 2003 were evaluated for surface roughness (average surface roughness [Ra], mean peak height [Rpm], and maximum distance from peak to valley [Rmax]), nanohardness, and the ion-treated layer thickness. The difference in average Rmax (P = .033) and average Rpm (P = .008) was statistically significant, but there was no correlation between the average or maximum roughness parameters (average surface roughness, Rmax, and Rpm) and time in vivo (P > .05). Overall, nanohardness was greater for the low-friction ion-treated heads (P < .001); and it decreased with increasing time in vivo (P = .01). Ion treatment produces an increased surface hardness, but the advantage of this increased hardness appears to dissipate over time in vivo.

  8. Optimization of implant/bone attachment: The effects of implant surface porosity, bioactive ceramic coatings, and delivery of adsorbed growth factors

    NASA Astrophysics Data System (ADS)

    Melican, Mora Carolynne

    Various surface treatments and coating materials have been tested for use on metal alloy orthopaedic implants. Their purpose has been to enhance the bioactivity of the implant surfaces, and thus to increase the rate and degree of bony attachment in vivo in an attempt to hasten recovery time, increase implant service lifetime, and lessen pain associated with loosened orthopaedic implants. A series of in vivo and in vitro studies were performed to determine the influence of different implant surfaces including porous metal surfaces with varied porosity with depth, resorbable and non-resorbable plasma-sprayed hydroxyapatite (HA) coatings, and finally HA coatings with an adsorbed layer of human recombinant bone morphogenetic protein (rhBMP-2), an osteoinductive protein. Textured as-cast metal surfaces produced by investment casting in three dimensionally printed ceramic molds have exhibited superior bony ingrowth and attachment. Plasma-sprayed HA coatings have been shown to be appropriate substrates for osteoblast proliferation (particularly on highly crystalline HA) and stem cell proliferation (particularly on less crystalline HA). Less crystalline HA coatings have shown promise as delivery systems for different levels of rhBMP-2. The osteoinductive protein has been shown to remain active after delivery to the system, and was most effective when delivered in concentrations ranging from 30 to 50 ng/ml. Combinations of these surface treatments for metal implant surfaces warrant further investigation.

  9. Surface modification of Ti dental implants by Nd:YVO 4 laser irradiation

    NASA Astrophysics Data System (ADS)

    Braga, Francisco J. C.; Marques, Rodrigo F. C.; Filho, Edson de A.; Guastaldi, Antonio C.

    2007-09-01

    Surface modifications have been applied in endosteal bone devices in order to improve the osseointegration through direct contact between neoformed bone and the implant without an intervening soft tissue layer. Surface characteristics of titanium implants have been modified by addictive methods, such as metallic titanium, titanium oxide and hydroxyapatite powder plasma spray, as well as by subtractive methods, such as acid etching, acid etching associated with sandblasting by either AlO 2 or TiO 2, and recently by laser ablation. Surface modification for dental and medical implants can be obtained by using laser irradiation technique where its parameters like repetition rate, pulse energy, scanning speed and fluency must be taken into accounting to the appropriate surface topography. Surfaces of commercially pure Ti (cpTi) were modified by laser Nd:YVO 4 in nine different parameters configurations, all under normal atmosphere. The samples were characterized by SEM and XRD refined by Rietveld method. The crystalline phases αTi, βTi, Ti 6O, Ti 3O and TiO were formed by the melting and fast cooling processes during irradiation. The resulting phases on the irradiated surface were correlated with the laser beam parameters. The aim of the present work was to control titanium oxides formations in order to improve implants osseointegration by using a laser irradiation technique which is of great importance to biomaterial devices due to being a clean and reproducible process.

  10. On the Mechanisms of Hydrogen Implantation Induced Silicon Surface Layer Cleavage

    SciTech Connect

    Hochbauer, Tobias Franz

    2002-08-01

    The “Ion-Cut”, a layer splitting process by hydrogen ion implantation and subsequent annealing is a versatile and efficient technique of transferring thin silicon surface layers from bulk substrates onto other substrates, thus enabling the production of silicon-oninsulator (SOI) materials. Cleavage is induced by the coalescence of the highly pressurized sub-surface H2-gas bubbles, which form upon thermal annealing. A fundamental understanding of the basic mechanisms on how the cutting process occurs is still unclear, inhibiting further optimization of the Ion-Cut process. This work elucidates the physical mechanisms behind the Ion-Cut process in hydrogen-implanted silicon. The investigation of the cleavage process reveals the cut to be largely controlled by the lattice damage, generated by the hydrogen ion irradiation process, and its effects on the local stress field and the fracture toughness within the implantation zone rather than by the depth of maximum H-concentration. Furthermore, this work elucidates the different kinetics in the H-complex formations in silicon crystals with different conductivity types, and examines the mechanically induced damage accumulation caused by the crack propagation through the silicon sample in the splitting step of the Ion-Cut process. Additionally, the influence of boron pre-implantation on the Ion-Cut in hydrogen implanted silicon is investigated. These studies reveal, that both, the atomic interaction between the boron implant and the hydrogen implant and the shift of the Fermi level due to the electrical activation of the implanted boron have a tremendous enhancing effect on the Ion-Cut process.

  11. On the Mechanisms of Hydrogen Implantation Induced Silicon Surface Layer Cleavage

    SciTech Connect

    Hochbauer, Tobias

    2001-11-01

    The “Ion-Cut”, a layer splitting process by hydrogen ion implantation and subsequent annealing is a versatile and efficient technique of transferring thin silicon surface layers from bulk substrates onto other substrates, thus enabling the production of silicon-oninsulator (SOI) materials. Cleavage is induced by the coalescence of the highly pressurized sub-surface H2-gas bubbles, which form upon thermal annealing. A fundamental understanding of the basic mechanisms on how the cutting process occurs is still unclear, inhibiting further optimization of the Ion-Cut process. This work elucidates the physical mechanisms behind the Ion-Cut process in hydrogen-implanted silicon. The investigation of the cleavage process reveals the cut to be largely controlled by the lattice damage, generated by the hydrogen ion irradiation process, and its effects on the local stress field and the fracture toughness within the implantation zone rather than by the depth of maximum H-concentration. Furthermore, this work elucidates the different kinetics in the H-complex formations in silicon crystals with different conductivity types, and examines the mechanically induced damage accumulation caused by the crack propagation through the silicon sample in the splitting step of the Ion-Cut process. Additionally, the influence of boron pre-implantation on the Ion-Cut in hydrogen implanted silicon is investigated. These studies reveal, that both, the atomic interaction between the boron implant and the hydrogen implant and the shift of the Fermi level due to the electrical activation of the implanted boron have a tremendous enhancing effect on the Ion-Cut process.

  12. Novel Laser Ablation Technology for Surface Decontamination

    SciTech Connect

    Cheng, Chung H.

    2004-06-01

    Laser ablation for surface cleaning has been pursued for the removal of paint on airplanes. It has also been pursued for the cleaning of semiconductor surfaces. However, all these approaches have been pursued by laser ablation in air. For highly contaminated surface, laser ablation in air can easily cause secondary contamination. Thus it is not suitable to apply to achieve surface decontamination for DOE facilities since many of these facilities have radioactive contaminants on the surface. Any secondary contamination will be a grave concern. The objective of this project is to develop a novel technology for laser ablation in liquid for surface decontamination. It aims to achieve more efficient surface decontamination without secondary contamination and to evaluate the economic feasibility for large scale surface decontamination with laser ablation in liquid. When laser ablation is pursued in the solution, all the desorbed contaminants will be confined in liquid. The contaminants can be precipitated and subsequently contained in a small volume for disposal. It can reduce the risk of the decontamination workers. It can also reduce the volume of contaminants dramatically.

  13. Mechanism for diamond nucleation and growth on single crystal copper surfaces implanted with carbon

    NASA Technical Reports Server (NTRS)

    Ong, T. P.; Xiong, Fulin; Chang, R. P. H.; White, C. W.

    1992-01-01

    The nucleation and growth of diamond crystals on single-crystal copper surfaces implanted with carbon ions is studied. Microwave plasma-enhanced chemical-vapor deposition is used for diamond growth. The single-crystal copper substrates were implanted either at room or elevated temperature with carbon ions prior to diamond nucleation. This procedure leads to the formation of a graphite film on the copper surface which greatly enhances diamond crystallite nucleation. A simple lattice model is constructed for diamond growth on graphite as 111 line (diamond) parallel to 0001 line (graphite) and 110 line (diamond) parallel to 1 1 -2 0 (graphite).

  14. Mechanism for diamond nucleation and growth on single crystal copper surfaces implanted with carbon

    NASA Technical Reports Server (NTRS)

    Ong, T. P.; Xiong, Fulin; Chang, R. P. H.; White, C. W.

    1992-01-01

    The nucleation and growth of diamond crystals on single-crystal copper surfaces implanted with carbon ions is studied. Microwave plasma-enhanced chemical-vapor deposition is used for diamond growth. The single-crystal copper substrates were implanted either at room or elevated temperature with carbon ions prior to diamond nucleation. This procedure leads to the formation of a graphite film on the copper surface which greatly enhances diamond crystallite nucleation. A simple lattice model is constructed for diamond growth on graphite as 111 line (diamond) parallel to 0001 line (graphite) and 110 line (diamond) parallel to 1 1 -2 0 (graphite).

  15. [Modern methods for studying the surface of titanium implants (literature review)].

    PubMed

    Suba, Csongor; Velich, Norbert; Vörös, János; Turi, Csaba; Szabó, György

    2004-02-01

    Studies of the coatings found on the surface of titanium implants employed in oral surgery are indispensable for understanding the interactions between the organism and the implant. This paper surveys the theory and practical applicability of the methods most frequently applied to study the surface structure and composition of the material. Detailed accounts are given of various structure investigation methods: scanning electron microscopy, stereo scanning electron microscopy, X-ray diffraction, atomic force microscopy and interference microscopy; and of various composition investigation methods: secondary ion mass spectroscopy, X-ray photoelectron spectroscopy, Auger electron spectroscopy; and also of the corrosion procedures for the study of electrochemical behaviour.

  16. Enhancing the antibacterial performance of orthopaedic implant materials by fibre laser surface engineering

    NASA Astrophysics Data System (ADS)

    Chan, Chi-Wai; Carson, Louise; Smith, Graham C.; Morelli, Alessio; Lee, Seunghwan

    2017-05-01

    Implant failure caused by bacterial infection is extremely difficult to treat and usually requires the removal of the infected components. Despite the severe consequence of bacterial infection, research into bacterial infection of orthopaedic implants is still at an early stage compared to the effort on enhancing osseointegration, wear and corrosion resistance of implant materials. In this study, the effects of laser surface treatment on enhancing the antibacterial properties of commercially pure (CP) Ti (Grade 2), Ti6Al4V (Grade 5) and CoCrMo alloy implant materials were studied and compared for the first time. Laser surface treatment was performed by a continuous wave (CW) fibre laser with a near-infrared wavelength of 1064 nm in a nitrogen-containing environment. Staphylococcus aureus, commonly implicated in infection associated with orthopaedic implants, was used to investigate the antibacterial properties of the laser-treated surfaces. The surface roughness and topography of the laser-treated materials were analysed by a 2D roughness testing and by AFM. The surface morphologies before and after 24 h of bacterial cell culture were captured by SEM, and bacterial viability was determined using live/dead staining. Surface chemistry was analysed by XPS and surface wettability was measured using the sessile drop method. The findings of this study indicated that the laser-treated CP Ti and Ti6Al4V surfaces exhibited a noticeable reduction in bacterial adhesion and possessed a bactericidal effect. Such properties were attributable to the combined effects of reduced hydrophobicity, thicker and stable oxide films and presence of laser-induced nano-features. No similar antibacterial effect was observed in the laser-treated CoCrMo.

  17. Dental Implants.

    PubMed

    Griggs, Jason A

    2017-10-01

    Systematic reviews of literature over the period between 2008 and 2017 are discussed regarding clinical evidence for the factors affecting survival and failure of dental implants. The factors addressed include publication bias, tooth location, insertion torque, collar design, implant-abutment connection design, implant length, implant width, bone augmentation, platform switching, surface roughness, implant coatings, and the use of ceramic materials in the implant body and abutment. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Optically active surfaces formed by ion implantation and thermal treatment

    SciTech Connect

    Gea, L.A.; Boatner, L.A.; Evans, H.M.; Zuhr, R.

    1996-08-01

    Embedded VO{sub 2} precipitates have been formed in single-crystal sapphire by the ion co-implantation of vanadium and oxygen and subsequent thermal annealing. The embedded VO{sub 2} particles have been shown to exhibit an optical switching behavior that is comparable to that of continuous thin films. In this work, the mechanisms of formation of these optically active particles are investigated. It is shown that precipitation of the vanadium dioxide phase is favored when the thermal treatment is performed on an ion-damaged but still crystalline (rather than amorphized) Al{sub 2}O{sub 3} substrate. The best optical switching behavior is observed in this case, and this behavior is apparently correlated with a more-favorable dispersion of VO{sub 2} small particles inside the matrix.

  19. Surface modification of polymeric substrates by plasma-based ion implantation

    NASA Astrophysics Data System (ADS)

    Okuji, S.; Sekiya, M.; Nakabayashi, M.; Endo, H.; Sakudo, N.; Nagai, K.

    2006-01-01

    Plasma-based ion implantation (PBII) as a tool for polymer modification is studied. Polymeric films have good performances for flexible use, such as food packaging or electronic devices. Compared with inorganic rigid materials, polymers generally have large permeability for gases and moisture, which causes packaged contents and devices to degrade. In order to add a barrier function, surface of polymeric films are modified by PBII. One of the advantageous features of this method over deposition is that the modified surface does not have peeling problem. Besides, micro-cracks due to mechanical stress in the modified layer can be decreased. From the standpoint of mass production, conventional ion implantation that needs low-pressure environment of less than 10-3 Pa is not suitable for continuous large-area processing, while PBII works at rather higher pressure of several Pa. In terms of issues mentioned above, PBII is one of the most expected techniques for modification on flexible substrates. However, the mechanism how the barrier function appears by ion implantation is not well explained so far. In this study, various kinds of polymeric films, including polyethyleneterephthalate (PET), are modified by PBII and their barrier characteristics that depend on the ion dose are evaluated. In order to investigate correlations of the barrier function with implanted ions, modified surface is analyzed with X-ray photoelectron spectroscopy (XPS). It is assumed that the diffusion and sorption coefficients are changed by ion implantation, resulting in higher barrier function.

  20. Fast element mapping of titanium wear around implants of different surface structures.

    PubMed

    Meyer, Ulrich; Bühner, Martin; Büchter, Andre; Kruse-Lösler, Birgit; Stamm, Thomas; Wiesmann, Hans Peter

    2006-04-01

    The effect of unintended titanium release around oral implants remains a biological concern. The current study was undertaken to evaluate a new detection system of element mapping in biological probes. A new scanning electron microscopy-energy dispersive spectroscopy detection method was used to map the features of titanium contamination in peri-implant bone around implants with different surface structures. The amount of titanium wear was highest adjacent to titanium-plasma-sprayed surfaces, followed by sandblastered large grid acid-etched and smooth surfaces. A high sensitivity of titanium detection over large areas of bone tissue was observed. A high spatial resolution of titanium wear particles (20 nm) could be reached and correlated to the ultrastructural morphological features of peri-implant tissue. Cells adjacent to titanium wear revealed no signs of morphological alterations on a nanoscale level at early periods of implant/bone interaction. The new technique may serve as a fast and effective tool to evaluate titanium release effects in biological probes.

  1. Effects of zinc-substituted nano-hydroxyapatite coatings on bone integration with implant surfaces*

    PubMed Central

    Zhao, Shi-fang; Dong, Wen-jing; Jiang, Qiao-hong; He, Fu-ming; Wang, Xiao-xiang; Yang, Guo-li

    2013-01-01

    Objective: The purpose of this study was to investigate the effects of a zinc-substituted nano-hydroxyapatite (Zn-HA) coating, applied by an electrochemical process, on implant osseointegraton in a rabbit model. Methods: A Zn-HA coating or an HA coating was deposited using an electrochemical process. Surface morphology was examined using field-emission scanning electron microscopy. The crystal structure and chemical composition of the coatings were examined using an X-ray diffractometer (XRD) and Fourier transform infrared spectroscopy (FTIR). A total of 78 implants were inserted into femurs and tibias of rabbits. After two, four, and eight weeks, femurs and tibias were retrieved and prepared for histomorphometric evaluation and removal torque (RTQ) tests. Results: Rod-like HA crystals appeared on both implant surfaces. The dimensions of the Zn-HA crystals seemed to be smaller than those of HA. XRD patterns showed that the peaks of both coatings matched well with standard HA patterns. FTIR spectra showed that both coatings consisted of HA crystals. The Zn-HA coating significantly improved the bone area within all threads after four and eight weeks (P<0.05), the bone to implant contact (BIC) at four weeks (P<0.05), and RTQ values after four and eight weeks (P<0.05). Conclusions: The study showed that an electrochemically deposited Zn-HA coating has potential for improving bone integration with an implant surface. PMID:23733429

  2. Annealing Effects on the Surface Plasmon of MgO Implanted with Gold

    NASA Technical Reports Server (NTRS)

    Ueda, A.; Mu, R.; Tung, Y. -S.; Henderson, D. O.; White, C. W.; Zuhr, R. A.; Zhu, Jane G.; Wang, P. W.

    1997-01-01

    Gold ion implantation was carried out with the energy of 1.1 MeV into (100) oriented MgO single crystal. Implanted doses are 1, 3, 6, 10 x 10(exp 16) ions/sq cm. The gold irradiation results in the formation of gold ion implanted layer with a thickness of 0.2 microns and defect formation. In order to form gold colloids from the as-implanted samples, we annealed the gold implanted MgO samples in three kinds of atmospheres: (1)Ar only, (2)H2 and Ar, and (3)O2 and Ar. The annealing over 1200 C enhanced the gold colloid formation which shows surface plasmon resonance band of gold. The surface plasmon bands of samples annealed in three kinds of atmospheres were found to be at 535 nm (Ar only), 524 nm(H2+Ar), and 560 nm (02+Ar), The band positions of surface plasmon can be reversibly changed by an additional annealing.

  3. Deformation characteristics of the near-surface layers of zirconia ceramics implanted with aluminum ions

    NASA Astrophysics Data System (ADS)

    Ghyngazov, S. A.; Vasiliev, I. P.; Frangulyan, T. S.; Chernyavski, A. V.

    2015-10-01

    The effect of ion treatment on the phase composition and mechanical properties of the near-surface layers of zirconium ceramic composition 97 ZrO2-3Y2O3 (mol%) was studied. Irradiation of the samples was carried out by accelerated ions of aluminum with using vacuum-arc source Mevva 5-Ru. Ion beam had the following parameters: the energy of the accelerated ions E = 78 keV, the pulse current density Ji = 4mA / cm2, current pulse duration equal τ = 250 mcs, pulse repetition frequency f = 5 Hz. Exposure doses (fluence) were 1016 и 1017 ion/cm2. The depth distribution implanted ions was studied by SIMS method. It is shown that the maximum projected range of the implanted ions is equal to 250 nm. Near-surface layers were investigated by X-ray diffraction (XRD) at fixed glancing incidence angle. It is shown that implantation of aluminum ions into the ceramics does not lead to a change in the phase composition of the near-surface layer. The influence of implanted ions on mechanical properties of ceramic near-surface layers was studied by the method of dynamic nanoindentation using small loads on the indenter P=300 mN. It is shown that in ion- implanted ceramic layer the processes of material recovery in the deformed region in the unloading mode proceeds with higher efficiency as compared with the initial material state. The deformation characteristics of samples before and after ion treatment have been determined from interpretation of the resulting P-h curves within the loading and unloading sections by the technique proposed by Oliver and Pharr. It was found that implantation of aluminum ions in the near-surface layer of zirconia ceramics increases nanohardness and reduces the Young's modulus.

  4. Microwave-assisted fabrication of titanium implants with controlled surface topography for rapid bone healing.

    PubMed

    Kutty, Muralithran G; De, Alok; Bhaduri, Sarit B; Yaghoubi, Alireza

    2014-08-27

    Morphological surface modifications have been reported to enhance the performance of biomedical implants. However, current methods of introducing graded porosity involves postprocessing techniques that lead to formation of microcracks, delamination, loss of fatigue strength, and, overall, poor mechanical properties. To address these issues, we developed a microwave sintering procedure whereby pure titanium powder can be readily densified into implants with graded porosity in a single step. Using this approach, surface topography of implants can be closely controlled to have a distinctive combination of surface area, pore size, and surface roughness. In this study, the effect of various surface topographies on in vitro response of neonatal rat calvarial osteoblast in terms of attachment and proliferation is studied. Certain graded surfaces nearly double the chance of cell viability in early stages (∼one month) and are therefore expected to improve the rate of healing. On the other hand, while the osteoblast morphology significantly differs in each sample at different periods, there is no straightforward correlation between early proliferation and quantitative surface parameters such as average roughness or surface area. This indicates that the nature of cell-surface interactions likely depends on other factors, including spatial parameters.

  5. Implantable sensor technology: measuring bone and joint biomechanics of daily life in vivo

    PubMed Central

    2013-01-01

    Stresses and strains are major factors influencing growth, remodeling and repair of musculoskeletal tissues. Therefore, knowledge of forces and deformation within bones and joints is critical to gain insight into the complex behavior of these tissues during development, aging, and response to injury and disease. Sensors have been used in vivo to measure strains in bone, intraarticular cartilage contact pressures, and forces in the spine, shoulder, hip, and knee. Implantable sensors have a high impact on several clinical applications, including fracture fixation, spine fixation, and joint arthroplasty. This review summarizes the developments in strain-measurement-based implantable sensor technology for musculoskeletal research. PMID:23369655

  6. Implantable sensor technology: measuring bone and joint biomechanics of daily life in vivo.

    PubMed

    D'Lima, Darryl D; Fregly, Benjamin J; Colwell, Clifford W

    2013-01-31

    Stresses and strains are major factors influencing growth, remodeling and repair of musculoskeletal tissues. Therefore, knowledge of forces and deformation within bones and joints is critical to gain insight into the complex behavior of these tissues during development, aging, and response to injury and disease. Sensors have been used in vivo to measure strains in bone, intraarticular cartilage contact pressures, and forces in the spine, shoulder, hip, and knee. Implantable sensors have a high impact on several clinical applications, including fracture fixation, spine fixation, and joint arthroplasty. This review summarizes the developments in strain-measurement-based implantable sensor technology for musculoskeletal research.

  7. Mechanisms Involved in Osteoblast Response to Implant Surface Morphology

    NASA Astrophysics Data System (ADS)

    Boyan, Barbara D.; Lohmann, Christoph H.; Dean, David D.; Sylvia, Victor L.; Cochran, David L.; Schwartz, Zvi

    2001-08-01

    Osteoblasts respond to surface topography with altered morphology, proliferation, and differentiation. The effects observed vary with cell culture model and the topographical features of the surface. In general, increased surface roughness is associated with decreased proliferation and increased differentiation. Cell responses to hormones, growth factors, and cytokines are altered as well, as is autocrine production of these factors. The cells interact with the surface via integrin receptors, and their expression is also surface roughness-dependent. Integrin binding to cell attachment proteins activates signal transduction cascades, including those mediated by protein kinase C and phospholipase A2. These signaling pathways are also used by regulatory factors, which results in synergistic responses. Prostaglandins are important mediators of the surface effects, and both constitutive and inducible cyclooxygenase are involved.

  8. Technologies for Prolonging Cardiac Implantable Electronic Device Longevity.

    PubMed

    Lau, Ernest W

    2017-01-01

    Prolonged longevity of cardiac implantable electronic devices (CIEDs) is needed not only as a passive response to match the prolonging life expectancy of patient recipients, but will also actively prolong their life expectancy by avoiding/deferring the risks (and costs) associated with device replacement. CIEDs are still exclusively powered by nonrechargeable primary batteries, and energy exhaustion is the dominant and an inevitable cause of device replacement. The longevity of a CIED is thus determined by the attrition rate of its finite energy reserve. The energy available from a battery depends on its capacity (total amount of electric charge), chemistry (anode, cathode, and electrolyte), and internal architecture (stacked plate, folded plate, and spiral wound). The energy uses of a CIED vary and include a background current for running electronic circuitry, periodic radiofrequency telemetry, high-voltage capacitor reformation, constant ventricular pacing, and sporadic shocks for the cardiac resynchronization therapy defibrillators. The energy use by a CIED is primarily determined by the patient recipient's clinical needs, but the energy stored in the device battery is entirely under the manufacturer's control. A larger battery capacity generally results in a longer-lasting device, but improved battery chemistry and architecture may allow more space-efficient designs. Armed with the necessary technical knowledge, healthcare professionals and purchasers will be empowered to make judicious selection on device models and maximize the utilization of all their energy-saving features, to prolong device longevity for the benefits of their patients and healthcare systems.

  9. Plasma Surface Functionalized Polyetheretherketone for Enhanced Osseo-Integration at Bone-Implant Interface.

    PubMed

    Zhao, Ying; Wong, Hoi Man; Lui, So Ching; Chong, Eva Y W; Wu, Guosong; Zhao, Xiaoli; Wang, Chong; Pan, Haobo; Cheung, Kenneth M C; Wu, Shuilin; Chu, Paul K; Yeung, Kelvin W K

    2016-02-17

    This study aims at improving osseo-integration at the bone-implant interface of polyetheretherketone (PEEK) by water (H2O) and ammonia (NH3) plasma immersion ion implantation (PIII). The pertinent surface characteristics including surface energy, roughness, morphology, and chemical composition are investigated systematically and the in vitro biological performance is evaluated by cell adhesion and proliferation, alkaline phosphatase (ALP) activity, real-time RT-PCR evaluation, and mineralization tests. In vivo osseo-integration is examined via implanting samples into the distal femur of the rats. The hydrophilicity, surface roughness, cell adhesion, and proliferation, ALP activity, and osteogenic differentiation after H2O PIII or NH3 PIII are improved significantly. Furthermore, substantially enhanced osseo-integration is achieved in vivo. Nonline-of-sight plasma surface functionalization, which is particularly suitable for biomedical implants with an irregular geometry, does not alter the bulk compressive yield strength and elastic modulus of the materials. Consequently, the favorable bulk attributes of PEEK are preserved while the surface biological properties are enhanced thus boding well for wider orthopedic application of the biopolymer.

  10. Surface Modification of Biomedical and Dental Implants and the Processes of Inflammation, Wound Healing and Bone Formation

    PubMed Central

    Stanford, Clark M.

    2010-01-01

    Bone adaptation or integration of an implant is characterized by a series of biological reactions that start with bone turnover at the interface (a process of localized necrosis), followed by rapid repair. The wound healing response is guided by a complex activation of macrophages leading to tissue turnover and new osteoblast differentiation on the implant surface. The complex role of implant surface topography and impact on healing response plays a role in biological criteria that can guide the design and development of future tissue-implant surface interfaces. PMID:20162020

  11. An in vitro comparison of possibly bioactive titanium implant surfaces.

    PubMed

    Göransson, A; Arvidsson, A; Currie, F; Franke-Stenport, V; Kjellin, P; Mustafa, K; Sul, Y T; Wennerberg, A

    2009-03-15

    The aim of the study was to compare Ca and P formation (CaP) and subsequent bone cell response of a blasted and four different possibly bioactive commercially pure (cp) titanium surfaces; 1. Fluoride etched (Fluoride), 2. Alkali-heat treated (AH), 3. Magnesium ion incorporated anodized (TiMgO), and 4. Nano HA coated and heat treated (nano HA) in vitro. Furthermore, to evaluate the significance of the SBF formed CaP coat on bone cell response. The surfaces were characterized by Optical Interferometry, Scanning Electron Microscopy (SEM) and X-ray Photoelectron Spectroscopy (XPS). CaP formation was evaluated after 12, 24 and 72 h in simulated body fluid (SBF). Primary human mandibular osteoblast-like cells were cultured on the various surfaces subjected to SBF for 72 h. Cellular attachment, differentiation (osteocalcin) and protein production (TGF-beta(1)) was evaluated after 3 h and 10 days respectively. Despite different morphological appearances, the roughness of the differently modified surfaces was similar. The possibly bioactive surfaces gave rise to an earlier CaP formation than the blasted surface, however, after 72 h the blasted surface demonstrated increased CaP formation compared to the possibly bioactive surfaces. Subsequent bone cell attachment was correlated to neither surface roughness nor the amount of formed CaP after SBF treatment. In contrast, osteocalcin and TGF-beta(1) production were largely correlated to the amount of CaP formed on the surfaces. However, bone response (cell attachment, osteocalcin and TGF-F production) on the blasted controls were similar or increased compared to the SBF treated fluoridated, AH and TiMgO surface.

  12. Mechanical properties of nitrogen-rich surface layers on SS304 treated by plasma immersion ion implantation

    NASA Astrophysics Data System (ADS)

    Fernandes, B. B.; Mändl, S.; Oliveira, R. M.; Ueda, M.

    2014-08-01

    The formation of hard and wear resistant surface regions for austenitic stainless steel through different nitriding and nitrogen implantation processes at intermediate temperatures is an established technology. As the inserted nitrogen remains in solid solution, an expanded austenite phase is formed, accounting for these surface improvements. However, experiments on long-term behavior and exact wear processes within the expanded austenite layer are still missing. Here, the modified layers were produced using plasma immersion ion implantation with nitrogen gas and had a thickness of up to 4 μm, depending on the processing temperature. Thicker layers or those with higher surface nitrogen contents presented better wear resistance, according to detailed microscopic investigation on abrasion, plastic deformation, cracking and redeposition of material inside the wear tracks. At the same time, cyclic fatigue testing employing a nanoindenter equipped with a diamond ball was carried out at different absolute loads and relative unloadings. As the stress distribution between the modified layer and the substrate changes with increasing load, additional simulations were performed for obtaining these complex stress distributions. While high nitrogen concentration and/or thicker layers improve the wear resistance and hardness, these modifications simultaneously reduce the surface fatigue resistance.

  13. Surface thermal oxidation on titanium implants to enhance osteogenic activity and in vivo osseointegration

    NASA Astrophysics Data System (ADS)

    Wang, Guifang; Li, Jinhua; Lv, Kaige; Zhang, Wenjie; Ding, Xun; Yang, Guangzheng; Liu, Xuanyong; Jiang, Xinquan

    2016-08-01

    Thermal oxidation, which serves as a low-cost, effective and relatively simple/facile method, was used to modify a micro-structured titanium surface in ambient atmosphere at 450 °C for different time periods to improve in vitro and in vivo bioactivity. The surface morphology, crystallinity of the surface layers, chemical composition and chemical states were evaluated by field-emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). Cell behaviours including cell adhesion, attachment, proliferation, and osteogenic differentiation were observed in vitro study. The ability of the titanium surface to promote osseointegration was evaluated in an in vivo animal model. Surface thermal oxidation on titanium implants maintained the microstructure and, thus, both slightly changed the nanoscale structure of titanium and enhanced the crystallinity of the titanium surface layer. Cells cultured on the three oxidized titanium surfaces grew well and exhibited better osteogenic activity than did the control samples. The in vivo bone-implant contact also showed enhanced osseointegration after several hours of oxidization. This heat-treated titanium enhanced the osteogenic differentiation activity of rBMMSCs and improved osseointegration in vivo, suggesting that surface thermal oxidation could potentially be used in clinical applications to improve bone-implant integration.

  14. Surface thermal oxidation on titanium implants to enhance osteogenic activity and in vivo osseointegration

    PubMed Central

    Wang, Guifang; Li, Jinhua; Lv, Kaige; Zhang, Wenjie; Ding, Xun; Yang, Guangzheng; Liu, Xuanyong; Jiang, Xinquan

    2016-01-01

    Thermal oxidation, which serves as a low-cost, effective and relatively simple/facile method, was used to modify a micro-structured titanium surface in ambient atmosphere at 450 °C for different time periods to improve in vitro and in vivo bioactivity. The surface morphology, crystallinity of the surface layers, chemical composition and chemical states were evaluated by field-emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). Cell behaviours including cell adhesion, attachment, proliferation, and osteogenic differentiation were observed in vitro study. The ability of the titanium surface to promote osseointegration was evaluated in an in vivo animal model. Surface thermal oxidation on titanium implants maintained the microstructure and, thus, both slightly changed the nanoscale structure of titanium and enhanced the crystallinity of the titanium surface layer. Cells cultured on the three oxidized titanium surfaces grew well and exhibited better osteogenic activity than did the control samples. The in vivo bone-implant contact also showed enhanced osseointegration after several hours of oxidization. This heat-treated titanium enhanced the osteogenic differentiation activity of rBMMSCs and improved osseointegration in vivo, suggesting that surface thermal oxidation could potentially be used in clinical applications to improve bone-implant integration. PMID:27546196

  15. Titanium implants with modified surfaces: meta-analysis of in vivo osteointegration.

    PubMed

    Gasik, Michael; Braem, Annabel; Chaudhari, Amol; Duyck, Joke; Vleugels, Jozef

    2015-04-01

    Titanium-based implants are widely used in modern clinical practice, but their "optimal" properties in terms of porosity and topology, roughness and hydrophilic parameters are being a subject of intensive discussions. Recent in vitro results have shown a possibility to optimize the surface of an implant with maximal repelling of bacteria (Staphylococcus aureus, Staphylococcus epidermidis) and improvement in human osteogenic and endothelial cell adhesion, proliferation and differentiation. In this work, these different grades titanium implants were tested in vivo using the same analytical methodology. In addition to material parameters, key histomorphometrical parameters such a regeneration area, bone adaptation area and bone-to-implant contact were determined after 2 and 4weeks of implantation in rabbit animal model. Porous implants have more clear differences than non-porous ones, with the best optimum values obtained on hydrothermally treated electrophoretically deposited titanium. These in vivo data correlate well with the optimal prediction made by in vitro tests. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Influence of hydrogen fluence on surface blistering of H and He co-implanted Ge

    NASA Astrophysics Data System (ADS)

    Dai, Jiayun; Xue, Zhongying; Zhang, Miao; Wei, Xing; Wang, Gang; Di, Zengfeng

    2016-02-01

    The effect of hydrogen fluence on surface blistering of H and He co-implanted Ge is investigated using atom force microscope, X-ray diffraction and transmission electron microscopy. With a fixed He, we find that for 1 × 1016 cm-2 H implantation fluence, only a few small dome-shaped blisters appear, for 3 × 1016 cm-2 H implantation fluence, large blisters as well as craters are formed, while for 5 × 1016 cm-2 H implantation fluence, no blisters can be observed. The strain evolution and platelet forming tendency are found to be relevant for the different blistering phenomenon. The weak blistering phenomenon for 1 × 1016 cm-2 H implantation fluence may be attributed to less "free" H for the building up of internal pressure of platelets and the sustained growth of platelets. While the absence of blistering phenomenon for 5 × 1016 cm-2 H implantation fluence is likely due to the retarded relief of the decreased uniform compressive stress throughout the damage region.

  17. Outcome of smooth surface tunnel porous polyethylene orbital implants (Medpor SST) in children with retinoblastoma.

    PubMed

    Choi, Youn Joo; Park, Chaerin; Jin, Hyun Chul; Choung, Ho-Kyung; Lee, Min Joung; Kim, Namju; Khwarg, Sang In; Yu, Young Suk

    2013-12-01

    To evaluate the surgical outcome after the insertion of smooth surface tunnel porous polyethylene orbital implants (Medpor SST) in children with retinoblastoma. 44 consecutive children with retinoblastoma who underwent primary enucleation and Medpor SST implantation at Seoul National University Hospital from November 2004 to August 2009, with at least 24 months of follow-up were included. A retrospective review of cases was performed. Mean age at the time of surgery was 24.7 months (range 1-65 months). The diameter of the spherical implant was 20 mm in 36 patients (81.8%) and 18 mm in 8 patients (18.2%). During a mean follow-up period of 60.1 months (range 26-93 months), there were no cases of implant exposure, extrusion or infection. Transient conjunctival thinning developed in three patients, but all resolved with conservative treatment. Anophthalmic socket complications such as lower lid malposition (retraction or entropion) (n=10, 22.7%), blepharoptosis (n=8, 18.2%) and enophthalmos (n=2, 4.5%) developed, but most showed acceptable cosmesis. Medpor SST is relatively safe, allowing for a mean follow-up of 5 years in terms of implant exposure, and may be a good choice of orbital implant for children with retinoblastoma.

  18. Ion implantation effects on surface-mechanical properties of metals and polymers

    SciTech Connect

    Rao, G.R.

    1993-04-01

    Fatigue of 8 complex alloys based on Fe-13Cr-15Ni-2Mo-2Mn-0.2Ti-0.8Si- 0.06C, and single-crystal Fe-15Cr-15Ni, implanted with 400-keV B{sup +} and 550-keV N{sup +} (total dose 2.3{times}10{sup 16} ions/cm{sup 2}) was examined. 600 C creep was also examined. The dual implantation increased hardness but decreased fatigue life of the 8 complex alloys. An optimum strengthening level and a shift to grain boundary cracking were determined. The single crystals also showed reduced fatigue life after implantation. High temperature creep of E1 and B1 alloys were improved by the dual implantation. Four polymers (PE, polypropylene, polystyrene, polyethersulfone) were implanted with 200keV B{sup +} to 3 different doses. PS was also implanted with both B{sup +} and Ar{sup +}. Near-surface hardness and tribological properties were measured. The hardness increased with dose and energy; wear also improved, with an optimum dose. (DLC)

  19. Ion implantation effects on surface-mechanical properties of metals and polymers

    SciTech Connect

    Rao, G.R.

    1993-04-01

    Fatigue of 8 complex alloys based on Fe-13Cr-15Ni-2Mo-2Mn-0.2Ti-0.8Si- 0.06C, and single-crystal Fe-15Cr-15Ni, implanted with 400-keV B[sup +] and 550-keV N[sup +] (total dose 2.3[times]10[sup 16] ions/cm[sup 2]) was examined. 600 C creep was also examined. The dual implantation increased hardness but decreased fatigue life of the 8 complex alloys. An optimum strengthening level and a shift to grain boundary cracking were determined. The single crystals also showed reduced fatigue life after implantation. High temperature creep of E1 and B1 alloys were improved by the dual implantation. Four polymers (PE, polypropylene, polystyrene, polyethersulfone) were implanted with 200keV B[sup +] to 3 different doses. PS was also implanted with both B[sup +] and Ar[sup +]. Near-surface hardness and tribological properties were measured. The hardness increased with dose and energy; wear also improved, with an optimum dose. (DLC)

  20. A strontium-incorporated nanoporous titanium implant surface for rapid osseointegration.

    PubMed

    Zhang, Wenjie; Cao, Huiliang; Zhang, Xiaochen; Li, Guanglong; Chang, Qing; Zhao, Jun; Qiao, Yuqin; Ding, Xun; Yang, Guangzheng; Liu, Xuanyong; Jiang, Xinquan

    2016-03-07

    Rapid osseointegration of dental implants will shorten the period of treatment and enhance the comfort of patients. Due to the vital role of angiogenesis played during bone development and regeneration, it might be feasible to promote rapid osseointegration by modifying the implant surface to gain a combined angiogenesis/osteogenesis inducing capacity. In this study, a novel coating (MAO-Sr) with strontium-incorporated nanoporous structures on titanium implants was generated via a new micro-arc oxidation, in an attempt to induce angiogenesis and osteogenesis to enhance rapid osseointegration. In vitro, the nanoporous structure significantly enhanced the initial adhesion of canine BMSCs. More importantly, sustained release of strontium ions also displayed a stronger effect on the BMSCs in facilitating their osteogenic differentiation and promoting the angiogenic growth factor secretion to recruit endothelial cells and promote blood vessel formation. Advanced mechanism analyses indicated that MAPK/Erk and PI3K/Akt signaling pathways were involved in these effects of the MAO-Sr coating. Finally, in the canine dental implantation study, the MAO-Sr coating induced faster bone formation within the initial six weeks and the osseointegration effect was comparable to that of the commercially available ITI implants. These results suggest that the MAO-Sr coating has the potential for future use in dental implants.

  1. Surface modification by metal ion implantation forming metallic nanoparticles in an insulating matrix

    NASA Astrophysics Data System (ADS)

    Salvadori, M. C.; Teixeira, F. S.; Sgubin, L. G.; Cattani, M.; Brown, I. G.

    2014-08-01

    There is special interest in the incorporation of metallic nanoparticles in a surrounding dielectric matrix for obtaining composites with desirable characteristics such as for surface plasmon resonance, which can be used in photonics and sensing, and controlled surface electrical conductivity. We have investigated nanocomposites produced by metal ion implantation into insulating substrates, where the implanted metal self-assembles into nanoparticles. The nanoparticles nucleate near the maximum of the implantation depth profile (projected range), which can be estimated by computer simulation using the TRIDYN code. TRIDYN is a Monte Carlo simulation program based on the TRIM (Transport and Range of Ions in Matter) code that takes into account compositional changes in the substrate due to two factors: previously implanted dopant atoms, and sputtering of the substrate surface. Our study show that the nanoparticles form a bidimentional array buried a few nanometers below the substrate surface. We have studied Au/PMMA (polymethylmethacrylate), Pt/PMMA, Ti/alumina and Au/alumina systems. Transmission electron microscopy of the implanted samples show that metallic nanoparticles form in the insulating matrix. These nanocomposites have been characterized by measuring the resistivity of the composite layer as a function of the implantation dose. The experimental results are compared with a model based on percolation theory, in which electron transport through the composite is explained by conduction through a random resistor network formed by the metallic nanoparticles. Excellent agreement is found between the experimental results and the predictions of the theory. We conclude in that the conductivity process is due only to percolation (when the conducting elements are in geometric contact) and that the contribution from tunneling conduction is negligible.

  2. Airport Surface Movement Technologies: Atlanta Demonstrations Overview

    NASA Technical Reports Server (NTRS)

    Jones, Denise R.; Young, Steven D.

    1997-01-01

    A flight demonstration was conducted in August 1997 at the Hartsfield Atlanta (ATL) International Airport as part of low visibility landing and surface operations (LVLASO) research activities. This research was aimed at investigating technology to improve the safety and efficiency of aircraft movements on the surface during the operational phases of roll-out, turnoff, and taxi in any weather condition down to a runway visual range of 300 feet. The system tested at ATL was composed of airborne and ground-based components that were integrated to provide both the flight crew and controllers with supplemental information to enable safe, expedient surface operations. Experimental displays were installed on a Boeing 757-200 research aircraft in both headup and head-down formats. On the ground, an integrated system maintained surveillance of the airport surface and a controller interface provided routing and control instructions. While at ATL, the research aircraft performed a series of flight and taxi operations to show the validity of the operational concept at a major airport facility, to validate simulation findings, and to assess each of the individual technologies performance in an airport environment. The concept was demonstrated to over 100 visitors from the Federal Aviation Administration (FAA) and the aviation community. This paper gives an overview of the LVLASO system and ATL test activities.

  3. Platelet adhesion and plasma protein adsorption control of collagen surfaces by He + ion implantation

    NASA Astrophysics Data System (ADS)

    Kurotobi, K.; Suzuki, Y.; Nakajima, H.; Suzuki, H.; Iwaki, M.

    2003-05-01

    He + ion implanted collagen-coated tubes with a fluence of 1 × 10 14 ions/cm 2 were exhibited antithrombogenicity. To investigate the mechanisms of antithrombogenicity of these samples, plasma protein adsorption assay and platelet adhesion experiments were performed. The adsorption of fibrinogen (Fg) and von Willebrand factor (vWf) was minimum on the He + ion implanted collagen with a fluence of 1 × 10 14 ions/cm 2. Platelet adhesion (using platelet rich plasma) was inhibited on the He + ion implanted collagen with a fluence of 1 × 10 14 ions/cm 2 and was accelerated on the untreated collagen and ion implanted collagen with fluences of 1 × 10 13, 1 × 10 15 and 1 × 10 16 ions/cm 2. Platelet activation with washed platelets was observed on untreated collagen and He + ion implanted collagen with a fluence of 1 × 10 14 ions/cm 2 and was inhibited with fluences of 1 × 10 13, 1 × 10 15 and 1 × 10 16 ions/cm 2. Generally, platelets can react with a specific ligand inside the collagen (GFOGER sequence). The results of platelets adhesion experiments using washed platelets indicated that there were no ligands such as GFOGER on the He + ion implanted collagen over a fluence of 1 × 10 13 ions/cm 2. On the 1 × 10 14 ions/cm 2 implanted collagen, no platelet activation was observed due to the influence of plasma proteins. From the above, it is concluded that the decrease of adsorbed Fg and vWf caused the antithrombogenicity of He + ion implanted collagen with a fluence of 1 × 10 14 ions/cm 2 and that plasma protein adsorption took an important role repairing the graft surface.

  4. The role of angiogenesis in implant dentistry part I: Review of titanium alloys, surface characteristics and treatments

    PubMed Central

    Asatourian, Armen; Garcia-Godoy, Franklin; Sheibani, Nader

    2016-01-01

    Background Angiogenesis plays an important role in osseointegration process by contributing to inflammatory and regenerative phases of surrounding alveolar bone. The present review evaluated the effect of titanium alloys and their surface characteristics including: surface topography (macro, micro, and nano), surface wettability/energy, surface hydrophilicity or hydrophobicity, surface charge, and surface treatments of dental implants on angiogenesis events, which occur during osseointegration period. Material and Methods An electronic search was performed in PubMed, MEDLINE, and EMBASE databases via OVID using the keywords mentioned in the PubMed and MeSH headings regarding the role of angiogenesis in implant dentistry from January 2000-April 2014. Results Of the 2,691 articles identified in our initial search results, only 30 met the inclusion criteria set for this review. The hydrophilicity and topography of dental implants are the most important and effective surface characteristics in angiogenesis and osteogenesis processes. The surface treatments or modifications of dental implants are mainly directed through the enhancement of biological activity and functionalization in order to promote osteogenesis and angiogenesis, and accelerate the osseointegration procedure. Conclusions Angiogenesis is of great importance in implant dentistry in a manner that most of the surface characteristics and treatments of dental implants are directed toward creating a more pro-angiogenic surface on dental implants. A number of studies discussed the effect of titanium alloys, dental implant surface characteristic and treatments on agiogenesis process. However, clinical trials and in-vivo studies delineating the mechanisms of dental implants, and their surface characteristics or treatments, action in angiogenesis processes are lagging. Key words:Angiogenesis, dental implant, osseointergration. PMID:27031073

  5. RTV silicone rubber surface modification for cell biocompatibility by negative-ion implantation

    NASA Astrophysics Data System (ADS)

    Zheng, Chenlong; Wang, Guangfu; Chu, Yingjie; Xu, Ya; Qiu, Menglin; Xu, Mi

    2016-03-01

    A negative cluster ion implantation system was built on the injector of a GIC4117 tandem accelerator. Next, the system was used to study the surface modification of room temperature vulcanization silicone rubber (RTV SR) for cell biocompatibility. The water contact angle was observed to decrease from 117.6° to 99.3° as the C1- implantation dose was increased to 1 × 1016 ions/cm2, and the effects of C1-, C2- and O1- implantation result in only small differences in the water contact angle at 3 × 1015 ions/cm2. These findings indicate that the hydrophilicity of RTV SR improves as the dose is increased and that the radiation effect has a greater influence than the doping effect on the hydrophilicity. There are two factors influence hydrophilicity of RTV: (1) based on the XPS and ATR-FTIR results, it can be inferred that ion implantation breaks the hydrophobic functional groups (Sisbnd CH3, Sisbnd Osbnd Si, Csbnd H) of RTV SR and generates hydrophilic functional groups (sbnd COOH, sbnd OH, Sisbnd (O)x (x = 3,4)). (2) SEM reveals that the implanted surface of RTV SR appears the micro roughness such as cracks and wrinkles. The hydrophilicity should be reduced due to the lotus effect (Zhou Rui et al., 2009). These two factors cancel each other out and make the C-implantation sample becomes more hydrophilic in general terms. Finally, cell culture demonstrates that negative ion-implantation is an effective method to improve the cell biocompatibility of RTV SR.

  6. Ion implantation of Ti + C to reduce friction and wear on steel surfaces

    SciTech Connect

    Follstaedt, D.M.; Pope, L.E.

    1987-01-01

    Within the last decade, ion implantation has been investigated for use in improving the surface-related mechanical properties of metal alloys. The treatment has improved the performance of device components and is now being used commercially in selected applications. A notable accomplishment is the reduction of wear by nitrogen implantation of many steel components used in mild wear applications. Another treatment receiving intensive investigation is the implantation of Ti + C into steels. This procedure not only reduces wear of steels, but has two important benefits beyond those obtained with nitrogen implantation: (a) friction is also reduced and (b) the reductions extend to hard bearing steels. Benefits have been obtained for all ferrous materials examined with unlubricated pin-on-disk testing in air, which range from soft austenitic (Type 304) to hard martensitic (Types 52100 and 440C) steels. The reductions in friction and wear obtained with this treatment are due to the amorphous surface layer. Examination with TEM of wear tracks from tests exhibiting the reductions show that not only is implanted titanium still present, but the amorphous layer is intact across the track.

  7. Surgical therapy of peri-implantitis lesions by means of a bovine-derived xenograft: comparative results of a prospective study on two different implant surfaces.

    PubMed

    Roccuzzo, Mario; Bonino, Francesca; Bonino, Luca; Dalmasso, Paola

    2011-08-01

    The aim of this prospective study was to evaluate a regenerative surgical treatment modality for peri-implantitis lesions on two different implant surfaces. Twenty-six patients with one crater-like defect, around either TPS (Control) or SLA (Test) dental implants, with a probing depth (PD) ≥6 mm and no implant mobility, were included. The implant surface was mechanically debrided and treated using a 24% EDTA gel and a 1% chlorhexidine gel. The bone defect was filled with a bovine-derived xenograft (BDX) and the flap was sutured around the non-submerged implant. One-year follow-up demonstrated clinical and radiographic improvements. PDs were significantly reduced by 2.1±1.2 mm in the Control implants and by 3.4±1.7 mm in the Test implants. Complete defect fill was never found around Controls, while it occurred in three out of 12 Test implants. Bleeding on probing decreased from 91.1±12.4% (Control) and 75.0±30.2% (Test) to 57.1±38.5% (p=0.004) and 14.6±16.7% (p=0.003), respectively. Several deep pockets (≥6 mm) were still present after surgical therapy around Controls. Surface characteristics may have an impact on the clinical outcome following surgical debridement, disinfection of the contaminated surfaces and grafting with BDX. Complete fill of the bony defect seems not to be a predictable result. © 2011 John Wiley & Sons A/S.

  8. Histomorphometric evaluation of bioceramic molecular impregnated and dual acid-etched implant surfaces in the human posterior maxilla.

    PubMed

    Shibli, Jamil Awad; Grassi, Sauro; Piattelli, Adriano; Pecora, Gabriele E; Ferrari, Daniel S; Onuma, Tatiana; d'Avila, Susana; Coelho, Paulo G; Barros, Raquel; Iezzi, Giovanna

    2010-12-01

    Physical and bioceramic incorporation surface treatments at the nanometer scale showed higher means of bone-to-implant contact (BIC) and torque values compared with surface topography at the micrometer scale; however, the literature concerning the effect of nanometer scale parameters is sparse. The aim of this study was to evaluate the influence of two different implant surfaces on the percentage bone-to-implant contact (BIC%) and bone osteocyte density in the human posterior maxilla after 2 months of unloaded healing. The implants utilized presented dual acid-etched (DAE) surface and a bioceramic molecular impregnated treatment (Ossean®, Intra-Lock International, Boca Raton, FL, USA) serving as control and test, respectively. Ten subjects (59 ± 9 years of age) received two implants (one of each surface) during conventional implant surgery in the posterior maxilla. After the non-loaded period of 2 months, the implants and the surrounding tissue were removed by means of a trephine and were non-decalcified processed for ground sectioning and analysis of BIC%, bone density in threaded area (BA%), and osteocyte index (Oi). Two DAE implants were found to be clinically unstable at time of retrieval. Histometric evaluation showed significantly higher BIC% and Oi for the test compared to the control surface (p < .05), and that BA% was not significantly different between groups. Wilcoxon matched pairs test was used to compare the differences of histomorphometric variables between implant surfaces. The significance test was conducted at a 5% level of significance. The histological data suggest that the bioceramic molecular impregnated surface-treated implants positively modulated bone healing at early implantation times compared to the DAE surface. © 2009, Copyright the Authors. Journal Compilation © 2010, Wiley Periodicals, Inc.

  9. Histologic studies on osseointegration: soft tissues response to implant surfaces and components. A review.

    PubMed

    Piattelli, Adriano; Pontes, Ana Emilia Farias; Degidi, Marco; Iezzi, Giovanna

    2011-01-01

    It is important to clarify the potential response of different types of cells to different implant materials and topographies. Thus, in vitro studies are performed using cell cultures, in order to evaluate, among other characteristics, the morphology, orientation, proliferation and adhesion of the cells. Histology evaluation are performed in animals or humans to describe the physiological response to different surfaces.

  10. Room-temperature attachment of PLGA microspheres to titanium surfaces for implant-based drug release

    NASA Astrophysics Data System (ADS)

    Xiao, Dongqin; Liu, Qing; Wang, Dongwei; Xie, Tao; Guo, Tailin; Duan, Ke; Weng, Jie

    2014-08-01

    Drug release from implant surfaces is an effective approach to impart biological activities, (e.g., antimicrobial and osteogenic properties) to bone implants. Coatings of polylactide-based polymer are a candidate for this purpose, but a continuous (fully covering) coating may be non-optimal for implant-bone fixation. This study reports a simple room-temperature method for attaching poly (lactide-co-glycolide) (PLGA) microspheres to titanium (Ti) surfaces. Microspheres were prepared with polyvinyl alcohol (PVA) or polyvinylpyrrolidone (PVP) as the emulsifier. Microspheres were attached to Ti discs by pipetting as a suspension onto the surfaces followed by vacuum drying. After immersion in shaking water bath for 14 d, a substantial proportion of the microspheres remained attached to the discs. In contrast, if the vacuum-drying procedure was omitted, only a small fraction of the microspheres remained attached to the discs after immersion for only 5 min. Microspheres containing triclosan (a broad-spectrum antibiotic) were attached by porous-surfaced Ti discs. In vitro experiments showed that the microsphere-carrying discs were able to kill Staphylococcus aureus and Escherichia Coli, and support the adhesion and growth of primary rat osteoblasts. This simple method may offer a flexible technique for bone implant-based drug release.

  11. 77 FR 5813 - Cardiovascular Metallic Implants: Corrosion, Surface Characterization, and Nickel Leaching...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-06

    ... assessments to predict corrosion failure. In addition, there has been an increase in the use of nitinol, a... transcatheter-delivered therapies. Corrosion of implant devices made of nitinol and other nickel-containing... dependent on surface finishing for nitinol as well as for some other nickel-containing alloys. Through the...

  12. Enhanced osteointegration on tantalum-implanted polyetheretherketone surface with bone-like elastic modulus.

    PubMed

    Lu, Tao; Wen, Jin; Qian, Shi; Cao, Huiliang; Ning, Congqin; Pan, Xiaoxia; Jiang, Xinquan; Liu, Xuanyong; Chu, Paul K

    2015-05-01

    Polyetheretherketone (PEEK) possesses a similar elastic modulus as bones but yet suffers from bio-inertness and poor osteogenesis. In this work, tantalum ions are implanted energetically into PEEK by plasma immersion ion implantation (PIII) to form Ta2O5 nanoparticles in the near surface. Nanoindentation reveals that the surface elastic modulus of the Ta ion implanted PEEK is closer to that of human cortical bones. In vitro cell adhesion, alkaline phosphatase activity, collagen secretion, extracellular matrix mineralization, and real-time PCR analyses disclose enhanced adhesion, proliferation, and osteogenic differentiation of rat bone mesenchymal stem cells (bMSCs) on the Ta-PIII modified PEEK. In vivo evaluation of the cortico-cancellous rat femur model by means of mi