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Sample records for dental restoration permanent

  1. Mechanical properties of a permanent dental restorative material based on calcium aluminate.

    PubMed

    Loof, J; Engqvist, H; Ahnfelt, N-O; Lindqvist, K; Hermansson, L

    2003-12-01

    This paper deals with some important mechanical properties (hardness, dimensional stability, compressive and flexural strength) of an experimental version of a translucent calcium aluminate dental restorative material. All samples investigated have been made from pre-pressed tablets, with a compaction degree of approximately 60%, hydrated using a 0.15 wt % Li salt solution as an accelerator. The samples were stored in water at 37 degrees C between the measurements. As reference materials one composite, Tetric Ceram, and one glass ionomer, Fuji II, were used with specimens prepared according to the manufacturer's recommendations. For the reference materials some of the properties were published data. The results show that the calcium aluminate material has sufficient mechanical properties to be used as a permanent dental restorative taking as a reference the ISO 9917 and the ISO 4049 as well as the reference materials. In addition the results indicate that the mechanical properties are controlled by the microstructure, which is mainly determined by the grain size of the filler.

  2. Dentist and practice characteristics associated with restorative treatment of enamel caries in permanent teeth: multiple-regression modeling of observational clinical data from The National Dental PBRN

    PubMed Central

    Fellows, Jeffrey L; Gordan, Valeria V.; Gilbert, Gregg H.; Rindal, D. Brad; Qvist, Vibeke; Litaker, Mark S.; Benjamin, Paul; Flink, Håkan; Pihlstrom, Daniel J.; Johnson, Neil

    2014-01-01

    Purpose Current evidence in dentistry recommends non-surgical treatment to manage enamel caries lesions. However, surveyed practitioners report they would restore enamel lesions that are confined to the enamel. We used actual clinical data to evaluate patient, dentist, and practice characteristics associated with restoration of enamel caries, while accounting for other factors. Methods We combined data from a National Dental Practice-Based Research Network observational study of consecutive restorations placed in previously unrestored permanent tooth surfaces and practice/demographic data from 229 participating network dentists. Analysis of variance and logistic regression, using generalized estimating equations (GEE) and variable selection within blocks, were used to test the hypothesis that patient, dentist, and practice characteristics were associated with variations in enamel restorations of occlusal and proximal caries compared to dentin lesions, accounting for dentist and patient clustering. Results Network dentists from 5 regions placed 6,891 restorations involving occlusal and/or proximal caries lesions. Enamel restorations accounted for 16% of enrolled occlusal caries lesions and 6% of enrolled proximal caries lesions. Enamel occlusal restorations varied significantly (p<0.05) by patient age and race/ethnicity, dentist use of caries risk assessment, network region, and practice type. Enamel proximal restorations varied significantly (p<0.05) by dentist race/ethnicity, network region, and practice type. CLINICAL SIGNIFICANCE Identifying patient, dentist, and practice characteristics associated with enamel caries restorations can guide strategies to improve provider adherence to evidence-based clinical recommendations. PMID:25000667

  3. [Odontogenic maxillary sinusitis caused by dental restoration].

    PubMed

    Sato, Kiminori

    2014-06-01

    We report herein on 5 patients with odontogenic maxillary sinusitis caused by a dental restoration (caries cutting, cavity preparation, inlay restoration). Odontogenic maxillary sinusitis was noted following dental restoration. Even though the pulp cavity and dental pulp were intact, the odontogenic maxillary sinusitis occurred caused by an apical lesion. Infection by way of the dentinal tubules was suggested to be a cause of the pathophysiology. Endoscopic sinus surgery was indicated in patients with intractable odontogenic maxillary sinusitis caused by the dental restoration. Cone-beam x-ray CT was useful for the accurate diagnosis of odontogenic maxillary sinusitis caused by a dental restoration. Physicians should thus be aware of the possibility that a tooth, which has undergone dental restoration, may cause odontogenic maxillary sinusitis.

  4. Health Instruction Packages: Permanent Teeth, Dental Deposits, and Dental Instruments. Dientes Permanentes, Depositos Dentales y Instrumentos Dentales.

    ERIC Educational Resources Information Center

    Lind, Patricia; Germano, Catherine

    These five learning modules use text interspersed with illustrations and reinforcement exercises to instruct dental aide and dental hygiene students about jaw bones and gums, dental deposits, and dental instruments. The first four modules were prepared by Patricia Lind in both Spanish and English. "The Gum and Bone of Permanent Teeth" ("La Encia y…

  5. Ceramics as biomaterials for dental restoration.

    PubMed

    Höland, Wolfram; Schweiger, Marcel; Watzke, Ronny; Peschke, Arnd; Kappert, Heinrich

    2008-11-01

    Sintered ceramics and glass-ceramics are widely used as biomaterials for dental restoration, especially as dental inlays, onlays, veneers, crowns or bridges. Biomaterials were developed either to veneer metal frameworks or to produce metal-free dental restorations. Different types of glass-ceramics and ceramics are available and necessary today to fulfill customers' needs (patients, dentists and dental technicians) regarding the properties of the biomaterials and the processing of the products. All of these different types of biomaterials already cover the entire range of indications of dental restorations. Today, patients are increasingly interested in metal-free restoration. Glass-ceramics are particularly suitable for fabricating inlays, crowns and small bridges, as these materials achieve very strong, esthetic results. High-strength ceramics are preferred in situations where the material is exposed to high masticatory forces.

  6. Costing dental restorations in public sector dental clinics.

    PubMed

    Khairiyah, Abdul Muttalib; Razak, Ishak Abdul; Raja-Latifah, Raja Jalludin; Tan, Bee Siew; Norain, Abu Talib; Noor-Aliyah, Ismail; Natifah, Che Salleh; Rauzi, Ismail

    2009-04-01

    The objective of this study is to share cost analysis methodology and to obtain cost estimates for posterior restorations in public sector dental clinics. Two urban and 2 rural dental clinics in Selangor state were selected. Only cases of 1 posterior restoration per visit by dental officers were included over 6 months. One capsulated amalgam type, 1 capsulated tooth-colored, and 1 non-capsulated tooth-colored material were selected. A clinical pathway form was formulated to collect data per patient. Annual capital and recurrent expenditures were collected per clinic. The mean cost of an amalgam restoration was RM 30.96 (sdRM 7.86); and tooth-colored restorations ranged from RM 33.00 (sdRM 8.43) to RM 41.10 (sdRM 10.61). Wherein 1 USD = RM 2.8. Restoration costs were 35% to 55% higher in clinics in rural areas than in urban areas. The findings demonstrate economy of scale for clinic operation and restoration costs with higher patient load. Costs per restoration were higher in rural than in urban dental clinics. More studies are recommended to address the dearth of dental costs data in Malaysia.

  7. [Pulp treatment of young permanent teeth after traumatic dental injury].

    PubMed

    Qin, Man

    2009-06-01

    Dental trauma could be largely classified into three groups: Hard tissue injuries, pulp injuries and periodontal tissue injuries. Since pulp injuries are reported in tooth fracture, displacement and avulsion, it is commonly thought that pulp injuries were involved in almost every type of dental injuries. The sequelae of pulp tissue after dental injuries include pulp survival, pulp calcification and pulp necrosis. Dental trauma mostly occurs in 7-15 year-old children. The treatment and prognosis of dental trauma in children are more complicated than those in adults because of the developmental nature of the young permanent teeth. The evaluation of pulp damage and treatment after dental injuries in growing young permanent teeth are discussed in this paper.

  8. Esthetic-functional recovery of permanent posterior tooth using autogenous biological restoration.

    PubMed

    Botelho, A M; Tavano, K T A; Correa-Faria, P; Morato, L N S; Viana, M R

    2012-01-01

    Occlusal morphology and difficult access for cleaning permanent molars result in the buildup of bacterial plaque and the development of caries. One method known as biological restoration was carried out. This technique known as biological restoration, has as main restorative material a fragment obtained from a duly donated extracted human tooth. This case report describes the restoration of an extensively decayed molar through the bonding of a fragment obtained from a third molar extracted from the patient himself. Biological restoration is a low-cost option that offers satisfactory aesthetic, morphological and functional results.The morphological/functional reestablishment of posterior teeth can be obtained through biological restoration, which allows the recovery of properties inherent to the dental structure, offers satisfactory aesthetic results and low cost.

  9. Reasons for Placement of Restorations on Previously Unrestored Tooth Surfaces by Dental PBRN Dentists

    PubMed Central

    Nascimento, Marcelle M.; Gordan, Valeria V.; Qvist, Vibeke; Litaker, Mark S.; Rindal, D. Brad; Williams, O.D.; Fellows, Jeffrey L.; Ritchie, Lloyd K.; Mjör, Ivar A.; McClelland, Jocelyn; Gilbert, Gregg H.

    2010-01-01

    Objective To identify and quantify the reasons for placing restorations on unrestored permanent tooth surfaces and the dental materials used by Dental Practice-Based Research Network (DPBRN; www.DentalPBRN.org) dentists. Methods A total of 229 DPBRN practitioner-investigators collected data on 9,890 consecutive restorations from 5,810 patients. Information included: (1) reasons for restoring; (2) tooth and surfaces restored; and (3) restorative materials employed. Results Primary caries (85%) and non-carious defects (15%), which included abrasion/ abfraction/ erosion lesions and tooth fracture, were the main reasons for placement of restorations. Restorations due to caries were frequently placed on occlusal surfaces (49%), followed by distal, mesial, buccal/facial, lingual/palatal, and incisal surfaces. Amalgam was used for 46% of the molar and 45% of the premolar restorations. Directly placed resin-based composite (RBC) was used for 48% of the molar, 49% of the premolar, and 92% of the anterior restorations. Conclusion Dental caries on occlusal and proximal surfaces of molar teeth are the main reasons for placing restorations on previously unrestored tooth surfaces by DPBRN practitioner-investigators. RBC is the material most commonly used for occlusal and anterior restorations. Amalgam remains the material of choice to restore proximal caries in posterior teeth, although there are significant differences by DPBRN region. PMID:20354094

  10. Evaluation of enamel dental restoration interface by optical coherence tomography.

    PubMed

    de Melo, L S A; de Araujo, R E; Freitas, A Z; Zezell, D; Vieira, N D; Girkin, J; Hall, A; Carvalho, M T; Gomes, A S L

    2005-01-01

    Evaluation of molar dental restorations on enamel is performed using optical coherence tomography (OCT) with 10 microm resolution. Images of approximately 50 microm failure gaps in the restorations are demonstrated and the OCT images are compared with x-ray and optical microscopy pictures. The results demonstrate the potential of the technique for clinical evaluation of dental restorations.

  11. Microleakage reduction from newer esthetic restorative materials in permanent molars.

    PubMed

    Ferdianakis, K

    1998-01-01

    Through use of new technologies, such as air-abrasive devices, caries detector dyes, modern technology can increase the speed, comfort and success of dental restorations. However the issue of marginal adaptation has been an ongoing technical problem. Today with the more frequent use of posterior composite resins, poor marginal adaptation of resin is still the major cause of failure of the restoration. Material contraction from polymerization and possibly inappropriate preparation design are key factors in the longevity of the restorations. This study attempts to determine the more effective material and technique for reducing microleakage in composite restorations. An in vitro study using three hybrid composite resins was done to evaluate marginal microleakage. Extracted molars were chosen and evaluated for caries through the use of caries detector dye. Using air-abrasion, caries were removed and minimal preparations were done. The samples were divided into two groups. First group was restored with Herculite XRV and Heliomolar paste composites resins. The second group was restored with Revolution flowable composite resin. Also Opti-bond and Fortify were used as a bonding agent and surface penetrating sealant respectively. The teeth were properly finished, thermocycled and evaluated for leakage using 2% basic fuschin detector dye. All data were subjected to the nonparametric Mann-Whitney Rank Sum Test. The results revealed that Herculite XRV and Heliomolar paste composites had significantly higher microleakage formation (P < 0.03), and also they presented higher void formation (P < 0.0001) than Revolution flowable composite resin.

  12. Restoration of Non-carious Tooth Defects by Dentists in The Dental Practice-Based Research Network - DPBRN

    PubMed Central

    Nascimento, Marcelle M.; Gordan, Valeria V.; Qvist, Vibeke; Bader, James D.; Rindal, D. Brad; Williams, O. Dale; Gewartowski, Daniel; Fellows, Jeffrey L.; Litaker, Mark S.; Gilbert, Gregg H.

    2011-01-01

    Objective To quantify the reasons for placing restorations on non-carious tooth defects (NCTD) by Dental Practice-Based Research Network (DPBRN) dentists, and associated tooth, patient and dentist characteristics. Methods Data were collected on placement of 1,301 restorations due to NCTD by 178 DPBRN dentists. Information included: (1) main clinical occurrence or reason, other than dental caries, for restoring previously un-restored permanent tooth surfaces, (2) characteristics of patients who received treatment, (3) dentists’ and dental practices’ characteristics, (4) tooth and surfaces restored, and (5) restorative materials employed. Results Restorations were most often placed to treat abrasion, abfraction, and erosion (AAE) lesions (46%) and tooth fracture (31%). Patients older than 40 years received restorations mainly due to AAE (p<0.0001). Premolar and anterior teeth were mostly restored due to AAE; molar teeth were mostly restored due to tooth fracture (p<0.0001). Directly placed resin-based composite (RBC) was largely used to restore AAE and tooth fracture (p<0.0001). Conclusion AAE and tooth fracture are the main reasons for restoring non-carious tooth surfaces among DPBRN practices. Premolar and anterior teeth of patients older than 40 years are most likely to receive restorations due to AAE; molars are most likely to receive restorations due to tooth fracture. Both types of NCTD are most often restored with RBC. PMID:22130438

  13. Repair or replacement of defective restorations by dentists in The Dental PBRN

    PubMed Central

    Gordan, Valeria V.; Riley, Joseph L.; Geraldeli, Saulo; Rindal, D. Brad; Qvist, Vibeke; Fellows, Jeffrey L.; Kellum, H. Paul; Gilbert, Gregg H.

    2011-01-01

    Objectives To (1) determine whether dentists in Dental Practice-based Research Network practices are more likely to repair versus replace a restoration that they diagnose as defective; (2) quantify the specific reasons for repairing or replacing; and (3) test the hypothesis that certain dentist, patient, and restoration-related variables are associated with the decision to repair versus replace. Methods This cross-sectional study used a consecutive patient/restoration recruitment design. Practitioner-investigators recorded data on consecutive restorations in permanent teeth that needed repair or replacement. DPBRN is a consortium of participating practices and dental organizations in the United States and Scandinavia. Data included the primary reason for repair or replacement, tooth surface(s) involved, restoration materials used, and patient demographics. Results Data for 9,484 restorations were collected from 7,502 patients in 197 practices. 75% (7,073) of restorations were replaced and 25% (2,411) repaired. Secondary caries was the main reason (43%, n=4,124) for treatment. Factors associated with greater likelihood of repair versus replace (p<.05) included: fewer years since dental school graduation, practicing in a solo or small group practice, being the dentist who placed the original restoration, older patient age, original restorative material was not amalgam, restoration of a molar, and fewer surfaces in the old restoration. Conclusion DPBRN dentists were more likely to replace than repair. Secondary caries was the most common reason for repairing or replacing existing restorations. Certain dentist, patient, and restoration-related variables were associated with the repair versus replace decision. PMID:22653939

  14. Radiographic diagnosis of dental restoration misfit: a systematic review.

    PubMed

    Liedke, G S; Spin-Neto, R; da Silveira, H E D; Wenzel, A

    2014-12-01

    The objective of this study was to perform a systematic review on the use of radiographic methods for the diagnosis of misfit in dental prostheses and restorations. The MEDLINE bibliographic database was searched from 1950 to February 2014 for reports on the radiographic diagnosis of misfits. The search strategy was limited to English-language publications using the following combined MeSH terms in the search strategy: (Dental Restoration OR Dental Prosthesis OR Crown OR Inlays OR Dental Abutments) and (Dental Leakage OR Prosthesis Fitting OR Dental Marginal Adaptation OR Surface Properties) and (Radiography, Dental OR Radiography, Dental, Digital OR Cone-Beam Computed Tomography). Twenty-eight publications were identified and read in full text, and 14 studies fulfilled criteria for inclusion. Information regarding the use of radiographic methods for the diagnosis of misfits in dental prosthesis and restorations, and in which the methodology/results comprised information regarding how the sample was collected/prepared, the method, imaging protocol, presence of a reference test and the outcomes were evaluated. QUADAS criteria was used to rate the studies in high, moderate or low quality. The evidence supporting the use of radiographic methods for the diagnosis of misfits in dental prosthesis and restorations is limited to low-/moderate-quality studies. The well-established intra-oral orthogonal projection is still under investigation and considered the most appropriate method, both when evaluating the relation between dental restoration to tooth and abutment to implant. Studies using digital radiographs have not evaluated the effect of image post-processing, and tomography has not been evaluated. PMID:25142004

  15. Radiographic diagnosis of dental restoration misfit: a systematic review.

    PubMed

    Liedke, G S; Spin-Neto, R; da Silveira, H E D; Wenzel, A

    2014-12-01

    The objective of this study was to perform a systematic review on the use of radiographic methods for the diagnosis of misfit in dental prostheses and restorations. The MEDLINE bibliographic database was searched from 1950 to February 2014 for reports on the radiographic diagnosis of misfits. The search strategy was limited to English-language publications using the following combined MeSH terms in the search strategy: (Dental Restoration OR Dental Prosthesis OR Crown OR Inlays OR Dental Abutments) and (Dental Leakage OR Prosthesis Fitting OR Dental Marginal Adaptation OR Surface Properties) and (Radiography, Dental OR Radiography, Dental, Digital OR Cone-Beam Computed Tomography). Twenty-eight publications were identified and read in full text, and 14 studies fulfilled criteria for inclusion. Information regarding the use of radiographic methods for the diagnosis of misfits in dental prosthesis and restorations, and in which the methodology/results comprised information regarding how the sample was collected/prepared, the method, imaging protocol, presence of a reference test and the outcomes were evaluated. QUADAS criteria was used to rate the studies in high, moderate or low quality. The evidence supporting the use of radiographic methods for the diagnosis of misfits in dental prosthesis and restorations is limited to low-/moderate-quality studies. The well-established intra-oral orthogonal projection is still under investigation and considered the most appropriate method, both when evaluating the relation between dental restoration to tooth and abutment to implant. Studies using digital radiographs have not evaluated the effect of image post-processing, and tomography has not been evaluated.

  16. Loss of Alloy in Cast Restorations Fabricated by Dental Students.

    ERIC Educational Resources Information Center

    Soh, George

    1991-01-01

    A study investigated the quantity of alloy lost in the fabrication of three types of cast restoration by dental students, and identified the proportion of loss at each of the four principal stages of the fabrication process. Suggestions for reducing metal loss and related costs in dental schools are offered. (MSE)

  17. Nonthermal Atmospheric Plasmas in Dental Restoration.

    PubMed

    Liu, Y; Liu, Q; Yu, Q S; Wang, Y

    2016-05-01

    It is well known that the service life of contemporary composite restoration is unsatisfactory, and longevity of dentin bonding is one of the major culprits. Bonding is essentially a hybridization process in which dental substrate and adhesive resin interact with each other through an exchange process. Thus, the longevity of dentin bonding can only be improved with enhanced qualities in substrate, adhesive resin, and their interaction within the hybridization zone. This review aims to collect and summarize recent advances in utilizing nonthermal atmospheric plasmas (NTAPs)-a novel technology that delivers highly reactive species in a gaseous medium at or below physiologic temperature-to improve the durability of dentin bonding by addressing these 3 issues simultaneously. Overall, NTAP has demonstrated efficacies in improving a number of critical properties for dentin bonding, including deactivation of oral pathogens, modification of surface chemistry/properties, resin polymerization, improvement in adhesive-dentin interactions, and establishment of auxiliary bonding mechanism. While a few preliminary studies have indicated the benefit of NTAP to bond strength and stability, additional researches are warranted to employ knowledge acquired so far and to evaluate these properties in a systematic way.

  18. Nonthermal Atmospheric Plasmas in Dental Restoration.

    PubMed

    Liu, Y; Liu, Q; Yu, Q S; Wang, Y

    2016-05-01

    It is well known that the service life of contemporary composite restoration is unsatisfactory, and longevity of dentin bonding is one of the major culprits. Bonding is essentially a hybridization process in which dental substrate and adhesive resin interact with each other through an exchange process. Thus, the longevity of dentin bonding can only be improved with enhanced qualities in substrate, adhesive resin, and their interaction within the hybridization zone. This review aims to collect and summarize recent advances in utilizing nonthermal atmospheric plasmas (NTAPs)-a novel technology that delivers highly reactive species in a gaseous medium at or below physiologic temperature-to improve the durability of dentin bonding by addressing these 3 issues simultaneously. Overall, NTAP has demonstrated efficacies in improving a number of critical properties for dentin bonding, including deactivation of oral pathogens, modification of surface chemistry/properties, resin polymerization, improvement in adhesive-dentin interactions, and establishment of auxiliary bonding mechanism. While a few preliminary studies have indicated the benefit of NTAP to bond strength and stability, additional researches are warranted to employ knowledge acquired so far and to evaluate these properties in a systematic way. PMID:26848068

  19. The demand for preventive and restorative dental services.

    PubMed

    Meyerhoefer, Chad D; Zuvekas, Samuel H; Manski, Richard

    2014-01-01

    Chronic tooth decay is the most common chronic condition in the United States among children ages 5-17 and also affects a large percentage of adults. Oral health conditions are preventable, but less than half of the US population uses dental services annually. We seek to examine the extent to which limited dental coverage and high out-of-pocket costs reduce dental service use by the nonelderly privately insured and uninsured. Using data from the 2001-2006 Medical Expenditure Panel Survey and an American Dental Association survey of dental procedure prices, we jointly estimate the probability of using preventive and both basic and major restorative services through a correlated random effects specification that controls for endogeneity. We found that dental coverage increased the probability of preventive care use by 19% and the use of restorative services 11% to 16%. Both conditional and unconditional on dental coverage, the use of dental services was not sensitive to out-of-pocket costs. We conclude that dental coverage is an important determinant of preventive dental service use, but other nonprice factors related to consumer preferences, especially education, are equal if not stronger determinants.

  20. The demand for preventive and restorative dental services.

    PubMed

    Meyerhoefer, Chad D; Zuvekas, Samuel H; Manski, Richard

    2014-01-01

    Chronic tooth decay is the most common chronic condition in the United States among children ages 5-17 and also affects a large percentage of adults. Oral health conditions are preventable, but less than half of the US population uses dental services annually. We seek to examine the extent to which limited dental coverage and high out-of-pocket costs reduce dental service use by the nonelderly privately insured and uninsured. Using data from the 2001-2006 Medical Expenditure Panel Survey and an American Dental Association survey of dental procedure prices, we jointly estimate the probability of using preventive and both basic and major restorative services through a correlated random effects specification that controls for endogeneity. We found that dental coverage increased the probability of preventive care use by 19% and the use of restorative services 11% to 16%. Both conditional and unconditional on dental coverage, the use of dental services was not sensitive to out-of-pocket costs. We conclude that dental coverage is an important determinant of preventive dental service use, but other nonprice factors related to consumer preferences, especially education, are equal if not stronger determinants. PMID:23349123

  1. Nanotechnology-based restorative materials for dental caries management

    PubMed Central

    Melo, Mary A.S.; Guedes, Sarah F.F.; Xu, Hockin H.K.; Rodrigues, Lidiany K.A.

    2013-01-01

    Nanotechnology has been applied to dental materials as an innovative concept for the development of materials with better properties and anticaries potential. In this review we discuss the current progress and future applications of functional nanoparticles incorporated in dental restorative materials as useful strategies to dental caries management. We also overview proposed antimicrobial and remineralizing mechanisms. Nanomaterials have great potential to decrease biofilm accumulation, inhibit the demineralization process, to be used for remineralizing tooth structure, and to combat caries-related bacteria. These results are encouraging and open the doors to future clinical studies that will allow the therapeutic value of nanotechnology-based restorative materials to be established. PMID:23810638

  2. Nanotechnology-based restorative materials for dental caries management.

    PubMed

    Melo, Mary A S; Guedes, Sarah F F; Xu, Hockin H K; Rodrigues, Lidiany K A

    2013-08-01

    Nanotechnology has been applied to dental materials as an innovative concept for the development of materials with better properties and anticaries potential. In this review we discuss the current progress and future applications of functional nanoparticles incorporated in dental restorative materials as useful strategies to dental caries management. We also overview proposed antimicrobial and remineralizing mechanisms. Nanomaterials have great potential to decrease biofilm accumulation, inhibit the demineralization process, to be used for remineralizing tooth structure, and to combat caries-related bacteria. These results are encouraging and open the doors to future clinical studies that will allow the therapeutic value of nanotechnology-based restorative materials to be established.

  3. Finite element calculation of residual stress in dental restorative material

    NASA Astrophysics Data System (ADS)

    Grassia, Luigi; D'Amore, Alberto

    2012-07-01

    A finite element methodology for residual stresses calculation in dental restorative materials is proposed. The material under concern is a multifunctional methacrylate-based composite for dental restorations, activated by visible light. Reaction kinetics, curing shrinkage, and viscoelastic relaxation functions were required as input data on a structural finite element solver. Post cure effects were considered in order to quantify the residual stresses coming out from natural contraction with respect to those debited to the chemical shrinkage. The analysis showed for a given test case that residual stresses frozen in the dental restoration at uniform temperature of 37°C are of the same order of magnitude of the strength of the dental composite material per se.

  4. Educational material of dental anatomy applied to study the morphology of permanent teeth.

    PubMed

    Siéssere, Selma; Vitti, Mathias; de Sousa, Luiz Gustavo; Semprini, Marisa; Regalo, Simone Cecílio Hallak

    2004-01-01

    The purpose of this report is to present educational material that would allow the dental student to learn to easily identify the morphologic characteristics of permanent teeth, and how they fit together (occlusion). In order to do this, macro models of permanent teeth with no attrition were carved in wax and later molded with alginate. These molds were filled with plaster, dental stone and/or cold-cured acrylic resin. The large individual dental stone tooth models were mounted on a wax base, thus obtaining maxillary and mandibular arches which were occluded. These dental arches were molded with plaster or dental stone. The authors suggest that these types of macro models allow an excellent visualization of the morphologic characteristics of permanent teeth and occlusion. Dental students are able to carve the permanent dentition in wax with great facility when they can observe macro models.

  5. Components of patient satisfaction with a dental restorative visit: results from The Dental Practice- Based Research Network

    PubMed Central

    Riley, Joseph L.; Rindal, D. Brad; Fellows, Jeffrey L.; Qvist, Vibeke; Patel, Sagar; Foy, Pat; Williams, O. Dale; Gilbert, Gregg H.

    2011-01-01

    Objectives Identify components of patient satisfaction with a dental restorative visit; and test the hypothesis that certain dentist, patient, and procedural factors are associated with patient satisfaction. Methods 197 practices in The Dental Practice-Based Research Network (DPBRN) recruited consecutive patients with defective restorations that were replaced or repaired in permanent teeth. At the end of the treatment visit, each subject was asked to complete a satisfaction survey and mail it directly to the DPBRN Regional Coordinators. Results Analysis of 5,879 satisfaction surveys revealed three satisfaction components which were interpersonal relationship-comfort attributes; material choice-value factors; and sensory-evaluative features. Satisfaction was highest among patients who received care in a private practice model; when the restoration was repaired rather than replaced; or when the restored tooth was not a molar. Conclusion These data suggest that a patient’s judgments of dentist’s skills and quality of care are based on personal interactions with the dentist, the level of comfort, and post-treatment sensitivity. These conclusions have direct implications for patient management before, during and after the procedure. Practice implications When taking a patient-centered approach, dentists should seek to understand how patients evaluate and rate the service provided, facilitating a focus on what each patient values most. PMID:22942147

  6. Effect of Industry Sponsorship on Dental Restorative Trials.

    PubMed

    Schwendicke, F; Tu, Y-K; Blunck, U; Paris, S; Göstemeyer, G

    2016-01-01

    Industry sponsorship was found to potentially introduce bias into clinical trials. We assessed the effects of industry sponsorship on the design, comparator choice, and findings of randomized controlled trials on dental restorative materials. A systematic review was performed via MEDLINE, CENTRAL, and EMBASE. Randomized trials on dental restorative and adhesive materials published 2005 to 2015 were included. The design of sponsored and nonsponsored trials was compared statistically (risk of bias, treatment indication, setting, transferability, sample size). Comparator choice and network geometry of sponsored and nonsponsored trials were assessed via network analysis. Material performance rankings in different trial types were estimated via Bayesian network meta-analysis. Overall, 114 studies were included (15,321 restorations in 5,232 patients). We found 21 and 41 (18% and 36%) trials being clearly or possibly industry sponsored, respectively. Trial design of sponsored and nonsponsored trials did not significantly differ for most assessed items. Sponsored trials evaluated restorations of load-bearing cavities significantly more often than nonsponsored trials, had longer follow-up periods, and showed significantly increased risk of detection bias. Regardless of sponsorship status, comparisons were mainly performed within material classes. The proportion of trials comparing against gold standard restorative or adhesive materials did not differ between trial types. If ranked for performance according to the need to re-treat (best: least re-treatments), most material combinations were ranked similarly in sponsored and nonsponsored trials. The effect of industry sponsorship on dental restorative trials seems limited.

  7. Various Effects of Sandblasting of Dental Restorative Materials

    PubMed Central

    Nishigawa, Goro; Maruo, Yukinori; Irie, Masao; Maeda, Naoto; Yoshihara, Kumiko; Nagaoka, Noriyuki; Matsumoto, Takuya; Minagi, Shogo

    2016-01-01

    Background Sandblasting particles which remain on the surfaces of dental restorations are removed prior to cementation. It is probable that adhesive strength between luting material and sandblasting particle remnants might exceed that with restorative material. If that being the case, blasting particles adhere to sandblasted material surface could be instrumental to increasing adhesive strength like underlying bonding mechanism between luting material and silanized particles of tribochemical silica coating-treated surface. We hypothesize that ultrasonic cleaning of bonding surfaces, which were pretreated with sandblasting, may affect adhesive strength of a resin luting material to dental restorative materials. Methods We therefore observed adhesive strength of resin luting material to aluminum oxide was greater than those to zirconia ceramic and cobalt-chromium alloy beforehand. To measure the shear bond strengths of resin luting material to zirconia ceramic and cobalt-chromium alloy, forty specimens of each restorative material were prepared. Bonding surfaces were polished with silicon abrasive paper and then treated with sandblasting. For each restorative material, 40 sandblasted specimens were equally divided into two groups: ultrasonic cleaning (USC) group and non-ultrasonic cleaning (NUSC) group. After resin luting material was polymerized on bonding surface, shear test was performed to evaluate effect of ultrasonic cleaning of bonding surfaces pretreated with sandblasting on bond strength. Results For both zirconia ceramic and cobalt-chromium alloy, NUSC group showed significantly higher shear bond strength than USC group. Conclusions Ultrasonic cleaning of dental restorations after sandblasting should be avoided to retain improved bonding between these materials. PMID:26764913

  8. [Dental restoration materials in pediatric dentistry].

    PubMed

    Davidson, C L

    1997-02-01

    Restorative materials in pediatric dentistry have to fulfill special requirements. They should be easy to handle and applicable in a not always dry mouth. They should potentially be adhesive in order to avoid too much mechanical preparation. They do not have to be extremely wear resistant as the dwell time of the restorations is relatively short. Glass-ionomer cements and in particular the resin modified types possess properties which make them almost ideal for the required purpose.

  9. Early failure of Class II resin composite versus Class II amalgam restorations placed by dental students.

    PubMed

    Overton, J D; Sullivan, Diane J

    2012-03-01

    Using the information from remake request slips in a dental school's predoctoral clinic, we examined the short-term survival of Class II resin composite restorations versus Class II dental amalgam restorations. In the student clinic, resin composite is used in approximately 58 percent of Class II restorations placed, and dental amalgam is used in the remaining 42 percent. In the period examined, Class II resin composite restorations were ten times more likely to be replaced at no cost to the patient than Class II dental amalgam restorations. A total of eighty-four resin composite restorations and six amalgam restorations were replaced due to an identified failure.

  10. What constitutes an ideal dental restorative material?

    PubMed

    Rekow, E D; Bayne, S C; Carvalho, R M; Steele, J G

    2013-11-01

    Intense environmental concerns recently have prompted dentistry to evaluate the performance and environmental impact of existing restoration materials. Doing so entices us to explore the 'what if?' innovation in materials science to create more ideal restorative materials. Articulating a specification for our design and evaluation methods is proving to be more complicated than originally anticipated. Challenges exist not only in specifying how the material should be manipulated and perform clinically but also in understanding and incorporating implications of the skill of the operator placing the restoration, economic considerations, expectations patients have for their investment, cost-effectiveness, influences of the health care system on how and for whom restorations are to be placed, and global challenges that limit the types of materials available in different areas of the world. The quandary is to find ways to actively engage multiple stakeholders to agree on priorities and future actions to focus future directions on the creation of more ideal restorative materials that can be available throughout the world.

  11. Effect of conventional dental restorative treatment on bacteria in saliva.

    PubMed

    Wright, J T; Cutter, G R; Dasanayake, A P; Stiles, H M; Caufield, P W

    1992-06-01

    Dental caries results from the dissolution of mineralized dental tissues by the metabolic by-products of oral bacteria colonizing the surface of teeth. The principal modality for dealing with this infectious process is through restorative treatment which removes the pathologic tissue and replaces it with a variety of inert materials. The purpose of this study was to evaluate the effect of traditional restorative treatment on select oral bacterial populations. Fifty-two females demonstrating high levels of mutans streptococci (greater than or equal to 2.5 x 10(4) colony forming units (cfu) per ml saliva) with no more than four missing posterior teeth were recruited for this study. Salivary levels of mutans streptococci, lactobacilli, total streptococci, and total cultivable bacteria were evaluated before, during, and after restorative treatment. Initial DMFS scores were established by two standardized examiners using bitewing radiographs and clinical examination, which was conducted under optimal conditions. All restorative treatment was completed by faculty members of the University of Alabama School of Dentistry using treatment plans developed by the DMFS examiners. The participants received a mean of 16.4 restored surfaces, which resulted in significant reductions of all the bacterial populations tested. All microbial populations monitored were predicted to return to their baseline levels within 151 days after restorative treatment in 50% of the participants. This study shows that conventional restorative treatment results in a significant reduction of bacterial populations including those associated with the dental caries process, i.e., mutans streptococci and lactobacilli.(ABSTRACT TRUNCATED AT 250 WORDS)

  12. Biomechanical Stress Analysis of Mandibular First Permanent Molar; Restored with Amalgam and Composite Resin: A Computerized Finite Element Study

    PubMed Central

    Prabhakar, AR

    2010-01-01

    Normal mastication with its varying magnitude and direction generates considerable reactionary stresses in teeth and their supporting tissues. The structure of the human tooth and its supporting tissues is a complex assemblage of materials of varied mechanical properties. The finite element method (FEM), a modern technique of numerical stress analysis, has the great advantage of being applicable to solids of irregular geometry and heterogeneous material properties and therefore ideally suited to the examination of structural behavior of teeth. The mandibular first permanent molar is one of the earliest permanent teeth to erupt in the oral cavity and hence most prone to caries. The purpose of the present study was to construct a two-dimensional FE model of the mandibular first permanent molar and its supporting structures, using a FE software called NISA II-Display III, EMRC, USA to study the following: • To compare stress distributions patterns when a modeled Class I Cavity was restored with dental amalgam and composite resin. • To compare the stress distributions pattern when the load was applied to different to locations, i.e.: At the mesial cusp tip, and at the center of the occlusal surface. Both amalgam and composite resin showed similar stress distribution pattern, however, the magnitudes of stresses generated in the tooth restored with composite resin were higher. Thus, amalgam is a better restorative material in distributing stresses.

  13. Analyses of dental pulp in restored teeth.

    PubMed

    Lentz, D L; Buchanan, J T; Basinger, D R

    1989-03-01

    Restored teeth were extracted from test animals at four time intervals (1 hour, 1 day, 1 week, and 3 months) following amalgam insertion. Extracted teeth were frozen in liquid nitrogen, cryo-fractured so as to expose the pulps and then freeze-dried. Pulps were analyzed for mercury content by energy dispersive spectrometry (EDS) and atomic absorption spectrophotometry (AAS). Mercury levels appeared below the detection limits of EDS but could be detected by AAS which showed the highest readings seven days after amalgam insertion. PMID:2740863

  14. Monitoring Wear On Dental Restoration Surfaces Using Microscope Photogrammetry

    NASA Astrophysics Data System (ADS)

    Mitchell, Harvey L.; Chadwick, R. G.; McCabe, John F.

    1989-04-01

    35mm photography of denture teeth and resin replicas through a convergent-axes microscope was used in an assessment of wear in dental restoration materials. The difficulty was to isolate and evaluate the significant photogrammetric parameters, but thereafter, the required depths could be calculated to accuracies of 0.01 mm r.m.s. using stereocomparator observations and quite simple formulae. The technique is applicable to biomedical laboratories which have access to an appropriate microscope if photogrammetric observations can be undertaken.

  15. [Exploration of basic restorative dental materials teaching in the field of dental technology].

    PubMed

    Jin, Yan-ting

    2012-12-01

    This study was to compare the difference of the existing course materials of basic restorative dental with the past materials, found out the weakness of teaching mode before the reform, and explored the reform in education through teaching content, method and evaluation, in order to improve the teaching quality.

  16. Restorative material and other tooth-specific variables associated with the decision to repair or replace defective restorations: findings from The Dental PBRN

    PubMed Central

    Gordan, Valeria V.; Riley, Joseph L.; Worley, Donald C.; Gilbert, Gregg H.

    2012-01-01

    Objectives Using data from dentists participating in The Dental Practice-Based Research Network (DPBRN), the study had 2 main objectives: (1) to identify and quantify the types of restorative materials in the existing failed restorations; and (2) to identify and quantify the materials used to repair or replace those failed restorations. Methods This cross-sectional study used a consecutive patient/restoration recruitment design. Practitioner-investigators recorded data on consecutive restorations in permanent teeth that needed repair or replacement. Data included the primary reason for repair or replacement, tooth surface(s) involved, restorative materials used, and patient demographics. Results Data for 9,875 restorations were collected from 7,502 patients in 197 practices for which 75% of restorations were replaced and 25% repaired. Most of the restorations that were either repaired or replaced were amalgam (56%) for which most (56%) of the material used was direct tooth-colored. The restorative material was 5 times more likely to be changed when the original restoration was amalgam (OR=5.2, p<.001). The likelihood of changing an amalgam restoration differed as a function of the tooth type (OR=3.0, p<.001), arch (OR=6.6, p<.001); and number of surfaces in the original restoration (OR=12.2, p<.001). Conclusion The probability of changing from amalgam to another restorative material differed with several characteristics of the original restoration. The change was most likely to take place when (1) the treatment was a replacement; (2) the tooth was not a molar; (3) the tooth was in the maxillary arch; and (4) the original restoration involved a single surface. PMID:22342563

  17. Recent Advances and Developments in Composite Dental Restorative Materials

    PubMed Central

    Cramer, N.B.; Stansbury, J.W.; Bowman, C.N.

    2011-01-01

    Composite dental restorations represent a unique class of biomaterials with severe restrictions on biocompatibility, curing behavior, esthetics, and ultimate material properties. These materials are presently limited by shrinkage and polymerization-induced shrinkage stress, limited toughness, the presence of unreacted monomer that remains following the polymerization, and several other factors. Fortunately, these materials have been the focus of a great deal of research in recent years with the goal of improving restoration performance by changing the initiation system, monomers, and fillers and their coupling agents, and by developing novel polymerization strategies. Here, we review the general characteristics of the polymerization reaction and recent approaches that have been taken to improve composite restorative performance. PMID:20924063

  18. Recent advances and developments in composite dental restorative materials.

    PubMed

    Cramer, N B; Stansbury, J W; Bowman, C N

    2011-04-01

    Composite dental restorations represent a unique class of biomaterials with severe restrictions on biocompatibility, curing behavior, esthetics, and ultimate material properties. These materials are presently limited by shrinkage and polymerization-induced shrinkage stress, limited toughness, the presence of unreacted monomer that remains following the polymerization, and several other factors. Fortunately, these materials have been the focus of a great deal of research in recent years with the goal of improving restoration performance by changing the initiation system, monomers, and fillers and their coupling agents, and by developing novel polymerization strategies. Here, we review the general characteristics of the polymerization reaction and recent approaches that have been taken to improve composite restorative performance. PMID:20924063

  19. Reasons underlying the extraction of permanent teeth in patients attending Peoples Dental College and Hospital.

    PubMed

    Dixit, L P; Gurung, C K; Gurung, N; Joshi, N

    2010-12-01

    Extraction of permanent teeth is common in Nepal. The study was undertaken to determine the causes and pattern of missing permanent teeth among patients attending Peoples Dental College and Hospital (PDCH) and to see if there is any association between variables like socio economic status, patient education level, dental visit and extraction of permanent teeth. A prospective cross sectional survey was carried out in patients attending the Department of Oral Surgery in PDCH between August 2006 and October 2006. The data was collected by trained clinician through clinical examination and using semi- structured questionnaires. Computer software SPSS 15 was used for statistical analysis. In age groups < or = 30 years, 90.0% it was reported that Dental caries was the most common reason for extraction of teeth. In age groups > 30 years, 55.6% periodontal disease was the most common reason for extraction of teeth. Distribution by type of teeth and dental disease was highly significant where. Dental caries was the reason for extraction of first permanent molar. Distribution by education level and visit to dentist was highly significant. About 93.1% of the people who were illiterate visited the dental surgeon while in pain and 76.0% of the university level graduates visited the dentist while in pain. Caries and its sequel remain the most important cause of tooth loss throughout adult life along with periodontal diseases at later stages.

  20. A Review of Developments in Computer-Based Systems to Image Teeth and Produce Dental Restorations

    PubMed Central

    Rekow, E. Dianne; Erdman, Arthur G.; Speidel, T. Michael

    1987-01-01

    Computer-aided design and manufacturing (CAD/CAM) make it possible to automate the creation of dental restorations. Currently practiced techniques are described. Three automated systems currently under development are described and compared. Advances in computer-aided design and computer-aided manufacturing (CAD/CAM) provide a new option for dentistry, creating an alternative technique for producing dental restorations. It is possible to create dental restorations that are automatically produced and meet or exceed current requirements for fit and occlusion.

  1. Comparative study of mechanical properties of dental restorative materials and dental hard tissues in compressive loads

    PubMed Central

    Lee, Jong Yeop

    2014-01-01

    There are two objectives. One is to show the differences in the mechanical properties of various dental restorative materials compared to those of enamel and dentin. The other is to ascertain which dental restorative materials are more suitable for clinical treatments. Amalgam, dental ceramic, gold alloy, dental resin, zirconia, and titanium alloy were processed as dental restorative material specimens. The specimens (width, height, and length of 1.2, 1.2, and 3.0 mm, respectively) were compressed at a constant loading speed of 0.1 mm/min. The maximum stress (115.0 ± 40.6, 55.0 ± 24.8, 291.2 ± 45.3, 274.6 ± 52.2, 2206.0 ± 522.9, and 953.4 ± 132.1 MPa), maximum strain (7.8% ± 0.5%, 4.0% ± 0.1%, 12.7% ± 0.8%, 32.8% ± 0.5%, 63.5% ± 14.0%, and 45.3% ± 7.4%), and elastic modulus (1437.5 ± 507.2, 1548.4 ± 583.5, 2323.4 ± 322.4, 833.1 ± 92.4, 3895.2 ± 202.9, and 2222.7 ± 277.6 MPa) were evident for amalgam, dental ceramic, gold alloy, dental resin, zirconia, and titanium alloy, respectively. The reference hardness value of amalgam, dental ceramic, gold alloy, dental resin, zirconia, and titanium alloy was 90, 420, 130–135, 86.6–124.2, 1250, and 349, respectively. Since enamel grinds food, its abrasion resistance is important. Therefore, hardness value should be prioritized for enamel. Since dentin absorbs bite forces, mechanical properties should be prioritized for dentin. The results suggest that gold alloy simultaneously has a hardness value lower than enamel (74.8 ± 18.1), which is important in the wear of the opposing natural teeth, and higher maximum stress, maximum strain, and elastic modulus than dentin (193.7 ± 30.6 MPa, 11.9% ± 0.1%, 1653.7 ± 277.9 MPa, respectively), which are important considering the rigidity to absorb bite forces. PMID:25352921

  2. Occurrence of dental caries in primary and permanent dentition, oral health status and treatment needs among 12-15 year old school children of Jorpati VDC, Kathmandu.

    PubMed

    Shrestha, N; Acharya, J; Sagtani, A R; Shrestha, R; Shrestha, S

    2014-12-01

    Dental caries occurrence, distribution, oral health status and corresponding treatment needs in 12 - 15 year old children are useful tools for evaluation of oral health. Dental caries status along with its treatment needs was recorded according to World Health Organization (WHO) index (1997) in 366 children from five schools within Jorpati Village Development Committee (VDC), Kathmandu. Dental caries was diagnosed in 156 (42.6%) children, out of which 122 (78.21%) had caries in permanent teeth, 26 (16.67%) had caries in primary teeth, and 8 (5.13%) had caries in both dentition. The age wise distribution of dental caries showed the highest prevalence among 12 year old students (23.8%) and the lowest among 15 year olds (3.8%). Among the female students (177), 43.5% showed presence of dental caries, while the prevalence among male students (179) was 41.8%.Out of the total number of teeth affected by dental caries (336), 273 (81.25%) were permanent teeth and 63 (18.75%) were primary teeth. The intra arch distribution of dental caries in permanent as well as primary dentition was statistically significant (P < 0.05). Restorative treatment (89.38%) was the main need in permanent dentition, and endodontic treatment (60.32%) in primary dentition. Chronologic enamel hypoplasia was found in 14 (3.83%) of the total population, and 62 (16.94%) required oral prophylaxis. These findings are significant as they can initiate further research in this area, which may help establish reliable baseline data for implementation of preventive oral health programs.

  3. Evaluation of Craniofacial Morphology of Children with Dental Fluorosis in Early Permanent Dentition Period

    PubMed Central

    Dogan, Alev Aksoy; Bolpaca, Pinar

    2009-01-01

    Objectives High intake of fluoride (>1.5 mg/L) for a prolonged period may lead to skeletal fluorosis as well as dental fluorosis. The aim of this study was to compare the craniofacial characteristics of children with dental fluorosis in early permanent dentition period to those without fluorosis. Methods Two hundred and sixteen children in early permanent dentition (girls:121, boys:95) were included in the study. Study group was composed of 124 children with dental fluorosis who was born and grew up in Isparta (girls:75, boys:49) whereas control group of children (n=92: 46 girls and 46 boys) had no dental fluorosis. Dental fluorosis was classified using Thylstrup Fejerskov Fluorosis Index. Radiological evaluation was performed by cephalometric tracing using Björk analysis. Statistical evaluation in between study and control groups was done by Independent Samples T test and comparison with Björk’s standards was done by One Sample T test analysis. The association between two quantitative variables was evaluated with Pearson’s correlation coefficient (rho). Results The mean dental fluorosis level was 4.6±1.8 for children with fluorosis. Systemic fluorosis affect girls no different than boys in the early permanent dentition period because none of the angular measurements show significant difference between boys and girls in the fluoridated group. Comparison of craniofacial angular values of boys with fluorosis show greater diversity compared to boys without fluorosis against Björk’s mean values for boys. Conclusions Craniofacial morphology of children with fluorosis did not show great diversity than the ones without fluorosis in the early permanent dentition period. None of the angular measurements were significantly different between boys and girls in the fluoridated group which might imply that systemic fluorosis did not show gender difference in the early permanent dentition. (Eur J Dent 2009;3:304–313) PMID:19826603

  4. Gold and palladium burden from dental restoration materials.

    PubMed

    Drasch, G; Muss, C; Roider, G

    2000-06-01

    From 81 volunteers (16 without dental restorations, 65 with gold crowns or inlays) samples of saliva before and after chewing gum, blood, serum, urine and faeces were taken and analysed for gold (Au) and palladium (Pd). The Au concentration in all analysed biomonitors correlates significantly to the number of teeth with gold restorations. For Pd the correlations were still significant, but weaker than for Au. Persons with gold restorations show maximal Au and Pd concentrations, 10(2)-10(3) higher than the background burden. The calculated maximal daily Au load in saliva (1.38 mg Au per day) reaches the range of an oral Au therapy for rheumatoid arthritis with 6 mg Auranofin (= 1.74 mg Au per day). During this therapy severe and frequent side effects are reported. In contrast, the Au concentration in serum maximally reached from Au restorations, amounts to only approximately 1/20 of the Au level during arthritis therapy. But even under subtherapeutic doses of 1 mg Auranofin/day severe side effects have been reported (4 out of 56 cases). The mean Au blood concentration from 1 mg Auranofin daily was only 3 times higher than our maximum value. A toxicological classification of the Pd values is difficult, because no toxicological threshold limit has been established, especially for the low-level long-term burden with Pd.

  5. Scattering and Absorption Properties of Biomaterials for Dental Restorative Applications

    NASA Astrophysics Data System (ADS)

    Fernandez-Oliveras, A.; Rubiño, M.; Pérez, M. M.

    2013-08-01

    The physical understanding of the optical properties of dental biomaterials is mandatory for their final success in restorative applications.Light propagation in biological media is characterized by the absorption coefficient, the scattering coefficient, the scattering phase function,the refractive index, and the surface conditions (roughness). We have employed the inverse adding-doubling (IAD) method to combine transmittance and reflectance measurements performed using an integrating-sphere setup with the results of the previous scattering-anisotropygoniometric measurements. This has led to the determination of the absorption and the scattering coefficients. The aim was to optically characterize two different dental-resin composites (nanocomposite and hybrid) and one type of zirconia ceramic, and comparatively study them. The experimental procedure was conducted under repeatability conditions of measurement in order to determine the uncertainty associated to the optical properties of the biomaterials. Spectral variations of the refraction index and the scattering anisotropy factor were also considered. The whole experimental procedure fulfilled all the necessary requirements to provide optical-property values with lower associated uncertainties. The effective transport coefficient presented a similar spectral behavior for the two composites but completely different for the zirconia ceramic. The results demonstrated that the scattering anisotropy exerted a clearly distinct impact on the optical properties of the zirconia ceramic compared with those of the dental-resin composites.

  6. Hardness and modulus of elasticity of primary and permanent teeth after wear against different dental materials

    PubMed Central

    Galo, Rodrigo; Contente, Marta Maria Martins Giamatei; Galafassi, Daniel; Borsatto, Maria Cristina

    2015-01-01

    Objectives: The purpose of this study was to determine the Young's modulus and the hardness of deciduous and permanent teeth following wear challenges using different dental materials. Materials and Methods: Wear challenges were performed against four dental materials: A resin-based fissure sealant (Fluoroshield®), a glass ionomer based fissure sealant (Vitremer®), and two microhybrid composite resins (Filtek Z250 and P90®). Using the pin-on-plate design, a deciduous or a permanent tooth was made into a pin (4 mm × 4 mm × 2 mm) working at a 3 N vertical load, 1 Hz frequency, and 900 cycles (15 min) with Fusayama artificial saliva as a lubricant. Before and after the tribological tests, the hardness and elasticity modulus of the tooth samples were measured by creating a nanoindentation at load forces up to 50 mN and 150 mN. All of the results were statistically analyzed using ANOVA and post-hoc Duncan's tests (P < 0.05). Results: No difference in hardness was encountered between deciduous and permanent teeth (P < 0.05) or modulus of elasticity (P < 0.05) before or after the wear challenges for all of the dental materials tested. Conclusions: Wear challenges against the studied dental materials did not alter the properties of permanent or deciduous teeth after the application of a 3 N load. PMID:26929700

  7. Dental Therapy Assistant: Quality of Restorations Placed and Finished.

    ERIC Educational Resources Information Center

    Heid, Theodore H.; Bair, Jeffrey H.

    The U.S. Army Dental Corps has implemented a new concept of dental care delivery, formally identified as the Improved Dental Care Delivery System. The concept is based on the conservation of professional manpower resources through the use of dental treatment teams employing expanded duty dental assistants. Dental Therapy Assistant (DTA) is the…

  8. Preservation of future options: restorative procedures on first permanent molars in children.

    PubMed

    Radcliffe, R M; Cullen, C L

    1991-01-01

    Stainless steel crowns are indicted for permanent teeth for multiple reasons. Indirect or direct pulp capping, pulpotomies, apexification procedures, and root canal therapy are treatments for permanent teeth that make them potential candidates for stainless steel crowns as interim restorations. The transitional dentition is divided into two stages: between five and eight years; and the period between ages nine and thirteen. Mesiodistal dimensions of the first permanent molars can be measured on study casts before preparation for the steel crown has begun. A flow chart is provided to give practitioners available options. Steps for preparing the stainless steel crown and technique for porcelain onlay preparation are also given.

  9. Prevalence and distribution of permanent canine agenesis in dental paediatric and orthodontic patients in Hungary.

    PubMed

    Rózsa, N; Nagy, K; Vajó, Z; Gábris, K; Soós, A; Alberth, M; Tarján, I

    2009-08-01

    Non-syndromic permanent canine agenesis, or combined with agenesis, or developmental absence of other tooth types, has occasionally been described in the literature, but isolated forms are rarely observed. The purpose of the present retrospective radiographic study was to provide data on the prevalence and distribution of permanent canine agenesis in the Hungarian population. Dental panoramic tomograms and the medical history data of 4417, 6- to 18-year-old children (average age 12 years, male-to-female ratio 1:1), who presented for treatment at the Department of Paediatric Dentistry and Orthodontics of the Semmelweis University Budapest, Hungary, were examined. Patients with systemic diseases were excluded. Chi-square and Fisher's tests were performed to determine statistical significance at a level of P < 0.05. Thirteen subjects had permanent canine agenesis. The overall prevalence was 0.29 per cent. The prevalence of permanent canine agenesis was 0.27 per cent in the maxilla and 0.09 per cent in the mandible (P < 0.01). The male-to-female ratio was 1:2.2. Dental anomalies associated with permanent canine agenesis were found: 11 patients had retention of the primary canines, 10 other types of agenesis of the permanent teeth, one a primary supernumerary tooth, one a supernumerary cusp, and nine occlusal disturbances. PMID:19474230

  10. Association between Chewing Side Preference and Dental Caries among Deciduous, Mixed and Permanent Dentition

    PubMed Central

    Sharma, Reena; Kashyap, Nilotpol; Prajapati, Deepesh; Kappadi, Damodar; Wadhwa, Saakshe; Gandotra, Shina; Yadav, Poonam

    2016-01-01

    Introduction Chewing Side Preference (CSP) is said to occur when mastication is recognized exclusively/consistently or predominantly on the same side of the jaw. It can be assessed by using the direct method - visual observation and indirect methods by electric programs, such as cinematography, kinetography and computerized electromyography. Aim The present study was aimed at evaluating the prevalence of CSP in deciduous, mixed and permanent dentitions and relating its association with dental caries. Materials and Methods In a cross-sectional observational study, 240 school going children aged 3 to 18years were randomly allocated to three experimental groups according to the deciduous dentition, mixed dentition and permanent dentition period. The existence of a CSP was determined using a direct method by asking the children to chew on a piece of gum (trident sugarless). The Mann Whitney U-test was used to compare the CSP and also among the boys and girls. The Spearman’s Correlation Coefficient was used to correlate CSP and dental caries among the three study groups and also among the groups. Results CSP was observed in 69%, 83% and 76% of children with primary, mixed and permanent dentition respectively (p>0.05). There was no statistically significant association between the presence of CSP and dental caries among the three study groups. Conclusion There was a weak or no correlation between gender and distribution of CSP and between presence of CSP and dental caries. PMID:27790569

  11. Prevalence of Dental Anomalies in Permanent Dentition of Brazilian Individuals with Down Syndrome

    PubMed Central

    Cuoghi, Osmar Aparecido; Topolski, Francielle; Perciliano de Faria, Lorraine; Occhiena, Carla Machado; Ferreira, Nancy dos Santos Pinto; Ferlin, Camila Ribeiro; Rogério de Mendonça, Marcos

    2016-01-01

    Objective: The aim of this study was to evaluate the incidence of dental anomalies in the permanent dentition of individuals with Down Syndrome (DS) to increase the knowledge on the dental issues in this syndrome. Method: One hundred and five panoramic X-rays of patients with DS (61 males and 44 females), aged 7 to 42 years were used. The data were statistically analyzed using bivariate analyses test (p <0.05). Results: Dental anomalies were observed in 50.47% of the sample. More than one anomaly was observed in 9.52% of the individuals. The most frequent dental anomalies were hypodontia and microdontia (16.19%), followed by retained tooth (10.47%), taurodontism (9.52%), supernumerary teeth (5.71%), macrodontia (2.85%) and root dilaceration (0.95%). There was no statistically significant difference between genders for any of the anomalies. Conclusion: A high prevalence of dental anomalies was observed in individuals with DS. The results of the present study reinforce the importance of good dental care, offering a greater basis for professionals who provide dental service to these patients. PMID:27733874

  12. Mechanical performance of novel bioactive glass containing dental restorative composites

    PubMed Central

    Khvostenko, D.; Mitchell, J. C.; Hilton, T. J.; Ferracane, J. L.; Kruzic, J. J.

    2013-01-01

    Objectives Bioactive glass (BAG) is known to possess antimicrobial properties and release ions needed for remineralization of tooth tissue, and therefore may be a strategic additive for dental restorative materials. The objective of this study was to develop BAG containing dental restorative composites with adequate mechanical properties comparable to successful commercially available composites, and to confirm the stability of these materials when exposed to a biologically challenging environment. Methods Composites with 72 wt.% total filler content were prepared while substituting 0–15% of the filler with ground BAG. Flexural strength, fracture toughness, and fatigue crack growth tests were performed after several different soaking treatments: 24 hours in DI water (all experiments), two months in brain-heart infusion (BHI) media+S. mutans bacteria (all experiments) and two months in BHI media (only for flexural strength). Mechanical properties of new BAG composites were compared along with the commercial composite Heliomolar by two-way ANOVA and Tukey’s multiple comparison test (p≤0.05). Results Flexural strength, fracture toughness, and fatigue crack growth resistance for the BAG containing composites were unaffected by increasing BAG content up to 15% and were superior to Heliomolar after all post cure treatments. The flexural strength of the BAG composites was unaffected by two months exposure to aqueous media and a bacterial challenge, while some decreases in fracture toughness and fatigue resistance were observed. The favorable mechanical properties compared to Heliomolar were attributed to higher filler content and a microstructure morphology that better promoted the toughening mechanisms of crack deflection and bridging. Significance Overall, the BAG containing composites developed in this study demonstrated adequate and stable mechanical properties relative to successful commercial composites. PMID:24050766

  13. Embryotoxicity assays for leached components from dental restorative materials

    PubMed Central

    2011-01-01

    Background Currently, there are no suitable assays available to evaluate the embryotoxicity of leached components from restorative dental materials. Methods The effect of the medium conditioned by composites and amalgam on mouse blastocysts in vitro was tested. The materials were also subcutaneously implanted, and the effect of the medium supplemented with serum from the host blood was evaluated in the embryotoxicity assay. The embryo implantation rate in the material-transplanted mothers was also evaluated. Results The results show that while the culture in media conditioned by amalgams did not affect blastocyst development, the medium conditioned by composites caused blastocyst degeneration and apoptosis. The development of blastocysts in a medium containing serum obtained from animals after transplantation was, however, without effect. Finally, inconsistent reduction in the implantation rate in transplanted mothers was observed. Conclusions In this study, we provide examples of in vitro and in vivo tests that may be used to evaluate embryotoxicity for dental materials. Our results show that leached components from our composite-material induced embryotoxicity in vitro, however, no toxicity was observed when subcutaneously implanted in vivo. This highlights the necessity of integrated in vitro and in vivo tests for valuable predictive estimation of embryotoxicity for complex materials. PMID:21978455

  14. A survey of dental practitioners in Wales to evaluate the management of deep carious lesions with vital pulp therapy in permanent teeth.

    PubMed

    Chin, J S; Thomas, M B; Locke, M; Dummer, P M H

    2016-09-23

    Objective To evaluate the management of deep carious lesions with vital pulp therapy in permanent teeth by dental practitioners within Wales.Design Postal questionnaire.Setting General practitioners (GDS), community (CDS) and hospital-based dentists (HDS) in Wales.Methods Community and hospital dental services with a remit for provision of restorative dentistry (CDS = 71; HDS = 46) and general dental practitioners (N = 510) were approached regarding their management of deep carious lesions with vital pulp therapy in permanent teeth. The postal questionnaire took the form of an anonymous survey. Questions covered usage parameters, training issues and reasons for material choice.Results The response rate was 29%. The majority of HDS (89%) used MTA or Biodentine for vital pulp therapy in contrast to GDS (41%) and CDS (32%). The main reasons cited for avoiding the use of MTA or Biodentine included cost, lack of training and difficulty in material handling.Conclusion Usage of MTA or Biodentine for vital pulp therapies is low in the general dental and community dental settings. Cost and lack of training are the main barriers for the uptake of these materials. Postgraduate training may be useful in addressing these barriers. Increasing their adoption would be advantageous as they have been shown to produce a more predictable outcome compared to traditional materials (for example, calcium hydroxide). PMID:27659637

  15. [Atraumatic restorative treatment in relation to pain, discomfort and dental treatment anxiety].

    PubMed

    Frencken, J E F M; Flohil, K A; de Baat, C

    2014-01-01

    Dental treatment anxiety usually develops during childhood due to a bad experience and the dental drill as well as the injection needle are the most common causes. The Atraumatic Restorative Treatment provides the opportunity to provoke little or no dental treatment anxiety because only hand instruments are used and local anaesthesia is seldom required. Several scientific studies have indicated that the Atraumatic Restorative Treatment causes less pain, discomfort and anxiety by comparison with conventional treatments. Therefore, the Atraumatic Restorative Treatment is considered to be promising for the treatment of carious lesions in anxious children and adults, and potentially also for patients suffering from dental treatment phobia. Furthermore, the Atraumatic Restorative Treatment may be indicated as the primary treatment method in children to prevent dental treatment anxiety and treatment under general anaesthesia. These conclusions must still be confirmed with responsible scientific research. PMID:25174188

  16. Understanding dental CAD/CAM for restorations - dental milling machines from a mechanical engineering viewpoint. Part A: chairside milling machines.

    PubMed

    Lebon, Nicolas; Tapie, Laurent; Duret, Francois; Attal, Jean-Pierre

    2016-01-01

    The dental milling machine is an important device in the dental CAD/CAM chain. Nowadays, dental numerical controlled (NC) milling machines are available for dental surgeries (chairside solution). This article provides a mechanical engineering approach to NC milling machines to help dentists understand the involvement of technology in digital dentistry practice. First, some technical concepts and definitions associated with NC milling machines are described from a mechanical engineering viewpoint. The technical and economic criteria of four chairside dental NC milling machines that are available on the market are then described. The technical criteria are focused on the capacities of the embedded technologies of these milling machines to mill both prosthetic materials and types of shape restorations. The economic criteria are focused on investment costs and interoperability with third-party software. The clinical relevance of the technology is assessed in terms of the accuracy and integrity of the restoration. PMID:27027102

  17. Understanding dental CAD/CAM for restorations - dental milling machines from a mechanical engineering viewpoint. Part A: chairside milling machines.

    PubMed

    Lebon, Nicolas; Tapie, Laurent; Duret, Francois; Attal, Jean-Pierre

    2016-01-01

    The dental milling machine is an important device in the dental CAD/CAM chain. Nowadays, dental numerical controlled (NC) milling machines are available for dental surgeries (chairside solution). This article provides a mechanical engineering approach to NC milling machines to help dentists understand the involvement of technology in digital dentistry practice. First, some technical concepts and definitions associated with NC milling machines are described from a mechanical engineering viewpoint. The technical and economic criteria of four chairside dental NC milling machines that are available on the market are then described. The technical criteria are focused on the capacities of the embedded technologies of these milling machines to mill both prosthetic materials and types of shape restorations. The economic criteria are focused on investment costs and interoperability with third-party software. The clinical relevance of the technology is assessed in terms of the accuracy and integrity of the restoration.

  18. Dental Composite Restorations and Psychosocial Function in Children

    PubMed Central

    Trachtenberg, Felicia L.; Hauser, Russ; McKinlay, Sonja; Shrader, Peter; Tavares, Mary; Bellinger, David C.

    2012-01-01

    BACKGROUND AND OBJECTIVE: Resin-based dental materials may intraorally release their chemical components and bisphenol A. The New England Children’s Amalgam Trial found that children randomized to amalgam had better psychosocial outcomes than those assigned to composites for posterior tooth restorations. The objective of this study was to examine whether greater exposure to dental composites is associated with psychosocial problems in children. METHODS: Analysis of treatment-level data from the New England Children’s Amalgam Trial, a 2-group randomized safety trial comparing amalgam with the treatment plan of bisphenol A-glycidyl methacrylate (bisGMA)-based composite and urethane dimethacrylate–based polyacid-modified composite (compomer), among 534 children aged 6 to 10 years at baseline. Psychosocial function at follow-up (n = 434) was measured by using the self-reported Behavior Assessment System for Children (BASC-SR) and parent-reported Child Behavior Checklist (CBCL). RESULTS: Children with higher cumulative exposure to bisGMA-based composite had poorer follow-up scores on 3 of 4 BASC-SR global scales: Emotional Symptoms (β = 0.8, SE = 0.3, P = .003), Clinical Maladjustment (β = 0.7, SE = 0.3, P = .02), and Personal Adjustment (β = –0.8, SE = 0.2, P = .002). Associations were stronger with posterior-occlusal (chewing) surfaces, where degradation of composite was more likely. For CBCL change, associations were not statistically significant. At-risk or clinically significant scores were more common among children with greater exposure for CBCL Total Problem Behaviors (16.3% vs 11.2%, P-trend = .01) and numerous BASC-SR syndromes (eg, ≥13 vs 0 surface-years, Interpersonal Relations 13.7% vs 4.8%, P-trend = .01). No associations were found with compomer, nor with amalgam exposure levels among children randomized to amalgam. CONCLUSIONS: Greater exposure to bisGMA-based dental composite restorations was associated with impaired psychosocial function

  19. Cluster Effects in a National Dental PBRN Restorative Study

    PubMed Central

    Litaker, M.S.; Gordan, V.V.; Rindal, D.B.; Fellows, J.L.; Gilbert, G.H.

    2013-01-01

    Items in clusters, such as patients of the same clinician or teeth within the same patient, tend to be more similar than items from different groups. This within-group similarity, represented by the intraclass correlation coefficient (ICC), reduces precision, yielding less statistical power and wider confidence intervals, compared with non-clustered samples of the same size. This must be considered in the design of studies including clusters. We present ICC estimates from a study of 7,826 restorations placed in previously unrestored tooth surfaces of 4,672 patients by 222 clinicians in the National Dental Practice-Based Research Network, as a resource for sample size planning in restorative studies. Our findings suggest that magnitudes of ICCs in practice-based research can be substantial. These can have large effects on precision and the power to detect treatment effects. Generally, we found relatively large ICCs for characteristics that are influenced by clinician choice (e.g., 0.36 for rubber dam use). ICCs for outcomes within individual patients, such as tooth surfaces affected by a caries lesion, tended to be smaller (from 0.03 to 0.15), but were still sufficiently large to substantially affect statistical power. Clustering should be taken into account in the design of oral health studies and derivation of statistical power estimates for these studies (ClinicalTrials.gov, NCT00847470). PMID:23857643

  20. Restorative Treatment Thresholds for Proximal Caries in Dental PBRN

    PubMed Central

    Kakudate, N.; Sumida, F.; Matsumoto, Y.; Manabe, K.; Yokoyama, Y.; Gilbert, G.H.; Gordan, V.V.

    2012-01-01

    This study was conducted to assess caries treatment thresholds among Japanese dentists and to identify characteristics associated with their decision to intervene surgically in proximal caries lesions within the enamel. Participants (n = 189) were shown radiographic images depicting interproximal caries and asked to indicate the lesion depth at which they would surgically intervene in both high- and low-caries-risk scenarios. Differences in treatment thresholds were then assessed via chi-square tests, and associations between the decision to intervene and dentist, practice, and patient characteristics were analyzed via logistic regression. The proportion of dentists who indicated surgical intervention into enamel was significantly higher in the high-caries-risk scenario (73.8%, N = 138) than in the low-caries-risk scenario (46.5%, N = 87) (p < 0.001). In multivariate analyses for a high-caries-risk scenario, gender of dentist, city population, type of practice, conducting caries-risk assessment, and administering diet counseling were significant factors associated with surgical enamel intervention. However, for a low-caries-risk scenario, city population, type of practice, and use of a dental explorer were the factors significantly associated with surgical enamel intervention. These findings demonstrate that restorative treatment thresholds for interproximal primary caries differ by caries risk. Most participants would restore lesions within the enamel for high-caries-risk individuals (Clinicaltrials.gov registration number NCT01680848). PMID:23053847

  1. Teaching atraumatic restorative treatment in U.S. dental schools: a survey of predoctoral pediatric dentistry program directors.

    PubMed

    Kateeb, Elham T; Warren, John J; Damiano, Peter; Momany, Elizabeth; Kanellis, Michael; Weber-Gasparoni, Karin; Ansley, Tim

    2013-10-01

    The International Dental Federation and World Health Organization have promoted the use of Atraumatic Restorative Treatment (ART) in modern clinical settings worldwide. In the United States, the practice of ART is not believed to be widely used, which may be a result of little attention given to ART training in predoctoral pediatric dentistry curricula in U.S. dental schools. This study investigated the extent of clinical and didactic instruction on ART provided in U.S. dental schools by surveying the predoctoral pediatric dentistry programs in 2010. Of the fifty-seven directors asked to complete the survey, forty-four responded for a response rate of 77 percent. Of these forty-four programs, 66 percent reported providing clinical training on ART, though only 14 percent provide this training often or very often. The types of ART training provided often or very often included interim treatment (18 percent) and single-surface cavities (14 percent) in primary teeth. However, ART was said to be rarely taught as a definitive treatment in permanent teeth (2 percent). Attitude was a major predictor, for clinical training provided and using professional guidelines in treatment decisions were associated with a positive attitude towards ART. These predoctoral pediatric dentistry programs used ART mainly in primary, anterior, and single-surface cavities and as interim treatment. As ART increases access of children to dental care, the incorporation of the ART approach into the curricula of U.S. dental schools should be facilitated by professional organizations.

  2. A useful and non-invasive microanalysis method for dental restoration materials

    NASA Astrophysics Data System (ADS)

    Hosoki, M.; Satsuma, T.; Nishigawa, K.; Takeuchi, H.; Asaoka, K.

    2012-12-01

    The elemental analysis of intraoral dental restorations provides considerable information for the treatment of dental metal allergy. Elemental analyses require specific instruments and complicated procedures, so this examination is not commonly carried out in private dental clinics. We describe a novel, simple and useful micro-analytical method for dental metal restorations. Micro metal dust was obtained by polishing the surface of restorative metal material with an unused silicone point (SUPER-SNAP). The metal dust on the silicone point was then rubbed onto adhesive tape, and this tape was covered with polyethylene film. The amount of metal dust material was <20 μg. An energy dispersive X-ray fluorescence spectrometer was used to carry out the elementary analysis of the metal dust on the polyethylene film. Three types of dental metal alloy materials of known components were examined. The results of elementary analyses were compared with the specifications provided by the manufacturer. The same procedure was carried out for three dental metal restorations of an adult female volunteer in vivo. The results of elemental analyses for five alloy materials exactly matched the product specification. Three metal samples obtained from intraoral restoration were also available for elemental analyses. The distinct advantage of this method is that it enables sample extraction without an invasive effect for the restoration. The metal sample is in a polyethylene film, so it is easy to mail it for inspection at specialist institutes yet it can be also be used in general dental clinics.

  3. Digital dental radiographic identification in the pediatric, mixed and permanent dentitions.

    PubMed

    Wood, R E; Kirk, N J; Sweet, D J

    1999-09-01

    The purpose of this paper is to investigate the utility of digital dental radiographic superimposition in the various stages of development of the human dentition. Digital, computer assisted dental identification is a means of identification which allows the spatial relationships of the root and support structures of the teeth to be compared one to the other. The technique has not been tested in patients with developing dentitions. Dental radiographs from patients in the pediatric, mixed and permanent dentition stages of development, simulating "antemortem" and "postmortem" radiographs, were digitized using a flat field radiograph scanner. Anatomic features were used as points of comparison utilizing image editing software whereby anatomic sections were digitally cut from the antemortem image and compared to the same anatomic locations on the postmortem image to assess for points of concordance. The technique was applied to 25 cases within the primary dentition, 25 cases within the mixed dentition and 25 cases within the permanent dentition. Results showed that this was a viable technique within both the pediatric and permanent dentition although it was of little value within the mixed dentition.

  4. Multi-material laser densification (MMLD) of dental restorations: Process optimization and properties evaluation

    NASA Astrophysics Data System (ADS)

    Li, Xiaoxuan

    This Ph.D. thesis proposes to investigate the feasibility of laser-assisted dental restoration and to develop a fundamental understanding of the interaction between laser beam and dental materials. Traditional dental restorations are produced by the porcelain-fused-to-metal (PFM) process, in which a dental restoration is cast from a metallic alloy and then coated with dental porcelains by multiple furnace-firing processes. PFM method is labor-intensive and hence very expensive. In order to fabricate dental restoration units faster and more cost-effectively, the Solid Freeform Fabrication (SFF) technique has been employed in this study. In particular, a Multi-Material Laser Densification (MMLD) process has been investigated for its potential to fabricate artificial teeth automatically from 3-D computer dental tooth files. Based on the principle of SFF, the MMLD process utilizes a micro-extruder system to deliver commercial dental alloy and porcelain slurry in a computer-controlled pattern line by line and layer by layer. Instead of firing the artificial tooth/teeth in a furnace, the extruded dental materials are laser scanned to convert the loose powder to a fully dense body. Different laser densification parameters including the densification temperature, laser output power, laser beam size, line dimension, ratio of the beam size to line width, beam scanning rate, processing atmosphere and pressure, dental powder state (powder bed or slurry), powder particle size, etc. have been used to evaluate their effects on the microstructures and properties of the laser densified dental body, and hence to optimize MMLD conditions. Furthermore, laser-scanning induced phase transformations in dental porcelains have been studied because the transformations have great impact on coefficient of thermal expansion (CTE) of dental porcelains, which should match that of dental alloy substrate. Since a single dental material line delivered by the MMLD system functions as a "construction

  5. Fluoride Release from Hollow Silica Microsphere-Containing Dental Restorative Acrylate Resin.

    PubMed

    Ji, Yuqin; Gao, Jun; Yin, Hengbo; Wang, Aili; Jiang, Tingshun; Wu, Gang; Wu, Zhanao

    2015-05-01

    Hollow silica microspheres with mesoporous shells were prepared by the sacrificial template method. Hollow silica microsphere-containing acrylate resin-based dental restoration materials were prepared by using hollow silica microspheres as NaF reservoirs. Fluoride release performances from naked hollow silica microspheres, acrylate resin, and hollow silica microsphere-containing acrylate resin-based dental restorative materials in an artificial saliva were investigated. The results showed that hollow silica microsphere-containing acrylate resin-based dental restorative materials had higher cumulative fluoride release quantities and sustained fluoride release rates than traditional acrylate resin-based dental restorative materials. Fluoride release could be tuned by changing the mesoporous shell thickness of hollow silica microsphere.

  6. Interim Restorative Approach for the Management of Congenitally Missing Permanent Mandibular Incisors: Presentation of Three Cases

    PubMed Central

    Prakash, Prashanth; Hallur, Jayadev M.; Gowda, Rachana Narse

    2011-01-01

    Congenital missing of mandibular permanent incisors with retained primary incisors may jeopardize the esthetic appearance and psychological development of children, especially during the years of transition into adolescence. The retained primary teeth are necessary for the maintenance and normal development of alveolar bone, which in turn is essential for future definitive rehabilitation. In such situations, an interim restoration may be provided before any definitive treatment is given to comfort the young patient during this transition period. Interim restorations may include resin-modified additions to the existing teeth as well as more sophisticated restorations such as resin-retained bridge and removable partial dentures. However, this restoration differs for different clinical situations based on various factors such as age and patient compliance, and also consideration has to be given for the growth changes of the child. The aim of this present paper is to discuss the esthetic management of three cases with bilateral agenesis of permanent mandibular incisors and retained primary incisors with composite interim restoration. PMID:22567446

  7. Influence of gag reflex on dental attendance, dental anxiety, self-reported temporomandibular disorders and prosthetic restorations.

    PubMed

    Akarslan, Z Z; Yıldırım Biçer, A Z

    2013-12-01

    To assess the influence of gag reflex severity, assessed according to the short form of the patient part of Gagging Problem Assessment Questionnaire (GPA-pa SF), on the dental attendance, dental anxiety, self-reported temporomandibular disorder (TMD) symptoms and presence of prosthetic restorations among patients requiring prosthodontic treatment in Turkey. A total of 505 patients (305 women; mean age: 46·35 years, SD: 28·2 years) undergoing dental examination were administered a questionnaire containing questions regarding their age, gender, education level, dental attendance, TMD symptoms (limitation in jaw opening, muscle pain, pain/sounds in the temporomandibular jaw), the Turkish version of the Modified Dental Anxiety Scale (MDAS) and the GPA-pa SF. Subsequently, any prosthetic restoration was recorded by a dentist. Descriptive statistics, one-way analysis of variance (anova) and the chi-square test were used for statistical analysis. Differences were found between GPA-pa SF scores 0, 1 and 2 for education level (P = 0·001), MDAS scores (P = 0·003), self-reported TMD (P = 0·000) and prosthesis wear (P = 0·000), but not for attendance patterns (P = 0·826). Patients with gag reflex had lower education levels, higher levels of dental anxiety, more self-reported TMD symptoms and fewer fixed or removable prosthetic restorations than patients without gag reflex. Gag reflex has impacts on dental anxiety, self-reported TMD and prosthetic restorations, but not on dental attendance patterns, according to the results of the GPA-pa SF. PMID:24118087

  8. Machinable glass-ceramics forming as a restorative dental material.

    PubMed

    Chaysuwan, Duangrudee; Sirinukunwattana, Krongkarn; Kanchanatawewat, Kanchana; Heness, Greg; Yamashita, Kimihiro

    2011-01-01

    MgO, SiO(2), Al(2)O(3), MgF(2), CaF(2), CaCO(3), SrCO(3), and P(2)O(5) were used to prepare glass-ceramics for restorative dental materials. Thermal properties, phases, microstructures and hardness were characterized by DTA, XRD, SEM and Vickers microhardness. Three-point bending strength and fracture toughness were applied by UTM according to ISO 6872: 1997(E). XRD showed that the glass crystallized at 892°C (second crystallization temperature+20°C) for 3 hrs consisted mainly of calcium-mica and fluorapatite crystalline phases. Average hardness (3.70 GPa) closely matched human enamel (3.20 GPa). The higher fracture toughness (2.04 MPa√m) combined with the hardness to give a lower brittleness index (1.81 µm(-1/2)) which indicates that they have exceptional machinability. Bending strength results (176.61 MPa) were analyzed by Weibull analysis to determine modulus value (m=17.80). Machinability of the calcium mica-fluorapatite glass-ceramic was demonstrated by fabricating with CAD/CAM. PMID:21597218

  9. Biofilm formation on dental restorative and implant materials.

    PubMed

    Busscher, H J; Rinastiti, M; Siswomihardjo, W; van der Mei, H C

    2010-07-01

    Biomaterials for the restoration of oral function are prone to biofilm formation, affecting oral health. Oral bacteria adhere to hydrophobic and hydrophilic surfaces, but due to fluctuating shear, little biofilm accumulates on hydrophobic surfaces in vivo. More biofilm accumulates on rough than on smooth surfaces. Oral biofilms mostly consist of multiple bacterial strains, but Candida species are found on acrylic dentures. Biofilms on gold and amalgam in vivo are thick and fully covering, but barely viable. Biofilms on ceramics are thin and highly viable. Biofilms on composites and glass-ionomer cements cause surface deterioration, which enhances biofilm formation again. Residual monomer release from composites influences biofilm growth in vitro, but effects in vivo are less pronounced, probably due to the large volume of saliva into which compounds are released and its continuous refreshment. Similarly, conflicting results have been reported on effects of fluoride release from glass-ionomer cements. Finally, biomaterial-associated infection of implants and devices elsewhere in the body is compared with oral biofilm formation. Biomaterial modifications to discourage biofilm formation on implants and devices are critically discussed for possible applications in dentistry. It is concluded that, for dental applications, antimicrobial coatings killing bacteria upon contact are more promising than antimicrobial-releasing coatings.

  10. Characteristics Identified for Success by Restorative Dental Science Department Chairpersons.

    PubMed

    Wee, Alvin G; Weiss, Robert O; Wichman, Christopher S; Sukotjo, Cortino; Brundo, Gerald C

    2016-03-01

    The primary aim of this study was to determine the characteristics that current chairpersons in restorative dentistry, general dentistry, prosthodontics, and operative dentistry departments in U.S. dental schools feel are most relevant in contributing to their success. The secondary aim was to determine these individuals' rankings of the importance of a listed set of characteristics for them to be successful in their position. All 82 current chairs of the specified departments were invited to respond to an electronic survey. The survey first asked respondents to list the five most essential characteristics to serve as chair of a department and to rank those characteristics based on importance. Participants were next given a list of ten characteristics in the categories of management and leadership and, without being aware of the category of each individual item, asked to rank them in terms of importance for their success. A total of 39 chairpersons completed the survey (47.6% response rate; 83.3% male and 16.2% female). In section one, the respondents reported that leadership, vision, work ethic, integrity, communication, and organization were the most essential characteristics for their success. In section two, the respondents ranked the leadership characteristics as statistically more important than the management characteristics (p<0.0001) for being successful in their positions.

  11. In situ reaction kinetic analysis of dental restorative materials

    NASA Astrophysics Data System (ADS)

    Younas, Basma; Samad Khan, Abdul; Muzaffar, Danish; Hussain, Ijaz; Chaudhry, Aqif Anwar; Rehman, Ihtesham Ur

    2013-12-01

    The objective of this study was to evaluate in situ structural and thermal changes of dental restorative materials at periodical time intervals. The commercial materials included zinc oxide eugenol (ZOE), zinc phosphate type I (ZnPO4), glass ionomer cement type II (GIC) and resin-based nano-omposite (Filtek Z350 XT). These materials were processed according to manufacturer's instructions. For the structural analysis Fourier transform infrared spectroscopy (FTIR) was used at high resolution. TGA was used to evaluate thermal weight-loss. The FTIR spectra were collected at periodic time intervals. FTIR spectra showed that with time passing all materials exhibited an increase in peak intensities and a new appearance of shoulders and shifting of peaks for example, ZnPO4 (P-O), ZOE (C═O, C═N, C-O-C), GIC (COO-, C-H, Si-OH), composites (C═O, C═C, C═N, C-N-H). The peaks were replaced by bands and these bands became broader with time interval. Composites showed a degree of conversion and new peaks corresponded to the cross-linking of polymer composites. TGA analysis showed that significant changes in weight loss of set materials were observed after 24 h, where ZOE showed continuous changes in thermal degradation. The spectral changes and thermal degradation with time interval elucidated in situ setting behaviour and understanding of their bonding compatibility with tooth structure and change in relation to time.

  12. Characteristics Identified for Success by Restorative Dental Science Department Chairpersons.

    PubMed

    Wee, Alvin G; Weiss, Robert O; Wichman, Christopher S; Sukotjo, Cortino; Brundo, Gerald C

    2016-03-01

    The primary aim of this study was to determine the characteristics that current chairpersons in restorative dentistry, general dentistry, prosthodontics, and operative dentistry departments in U.S. dental schools feel are most relevant in contributing to their success. The secondary aim was to determine these individuals' rankings of the importance of a listed set of characteristics for them to be successful in their position. All 82 current chairs of the specified departments were invited to respond to an electronic survey. The survey first asked respondents to list the five most essential characteristics to serve as chair of a department and to rank those characteristics based on importance. Participants were next given a list of ten characteristics in the categories of management and leadership and, without being aware of the category of each individual item, asked to rank them in terms of importance for their success. A total of 39 chairpersons completed the survey (47.6% response rate; 83.3% male and 16.2% female). In section one, the respondents reported that leadership, vision, work ethic, integrity, communication, and organization were the most essential characteristics for their success. In section two, the respondents ranked the leadership characteristics as statistically more important than the management characteristics (p<0.0001) for being successful in their positions. PMID:26933102

  13. Surface contact fatigue and flexural fatigue of dental restorative materials.

    PubMed

    McCabe, J F; Wang, Y; Braem, M

    2000-06-01

    Antagonistic contact on a dental restoration may produce surface and subsurface stresses leading to fatigue wear as well as to bulk stressing, eventually causing catastrophic failure. It was the aim of the present work to study the outcome of two different approaches to fatigue testing of materials involving either surface contact fatigue or flexural fatigue mechanisms. A range of materials was tested, including conventional glass-ionomers, resin-modified glass-ionomers, poly-acid modified composites, and composites. Materials were prepared and tested using both surface contact and flexural fatigue. The results show that conventional glass-ionomers have the least resistance to fatigue under both regimes while composites have the longest fatigue lives and the highest values of flexural fatigue limit. However, the results also support the fact that catastrophic failure should be investigated separately from surface contact fatigue. Within the group of composite products tested, a hybrid composite material had a significantly greater flexural fatigue limit than a microfilled one, but the latter material had a significantly greater surface contact fatigue life, indicating that wear behavior cannot be predicted from bulk fracture characteristics and vice versa. The process of wear occurs by a combination of a number of fundamental processes, and the contribution fatigue makes will vary according to the environment and nature of the material.

  14. Failure Rate of Direct High-Viscosity Glass-Ionomer Versus Hybrid Resin Composite Restorations in Posterior Permanent Teeth - a Systematic Review

    PubMed Central

    Mickenautsch, Steffen; Yengopal, Veerasamy

    2015-01-01

    Purpose Traditionally, resin composite restorations are claimed by reviews of the dental literature as being superior to glass-ionomer fillings in terms of restoration failures in posterior permanent teeth. The aim of this systematic review is to answer the clinical question, whether conventional high-viscosity glass-ionomer restorations, in patients with single and/or multi-surface cavities in posterior permanent teeth, have indeed a higher failure rate than direct hybrid resin composite restorations. Methods Eight databases were searched until December 02, 2013. Trials were assessed for bias risks, in-between datasets heterogeneity and statistical sample size power. Effects sizes were computed and statistically compared. A total of 55 citations were identified through systematic literature search. From these, 46 were excluded. No trials related to high-viscosity glass-ionomers versus resin composite restorations for direct head-to-head comparison were found. Three trials related to high-viscosity glass-ionomers versus amalgam and three trials related to resin composite versus amalgam restorations could be included for adjusted indirect comparison, only. Results The available evidence suggests no difference in the failure rates between both types of restoration beyond the play of chance, is limited by lack of head-to-head comparisons and an insufficient number of trials, as well as by high bias and in-between-dataset heterogeneity risk. The current clinical evidence needs to be regarded as too poor in order to justify superiority claims regarding the failure rates of both restoration types. Sufficiently large-sized, parallel-group, randomised control trials with high internal validity are needed, in order to justify any clinically meaningful judgment to this topic. PMID:26962372

  15. Contribution of prosthetic treatment considerations for dental extractions of permanent teeth.

    PubMed

    Fernández-Barrera, Miguel Ángel; Medina-Solís, Carlo Eduardo; Casanova-Rosado, Juan Fernando; Mendoza-Rodríguez, Martha; Escoffié-Ramírez, Mauricio; Casanova-Rosado, Alejandro José; Navarrete-Hernández, José de Jesús; Maupomé, Gerardo

    2016-01-01

    Background. Tooth loss is an easily identifiable outcome that summarizes a complex suite of factors in an individual's history of dental disease and its treatment by dental services over a lifetime. Assessment of overall tooth loss data is essential for epidemiologically evaluating the adequacy of dental care provided at a systems level, as well as for placing in context tooth loss for non-disease causes. For example, when derived from prosthetic treatment planning, the latter may unfortunately lead to some teeth being extracted (pulled) for the sake of better comprehensive clinical results. The objective of the present manuscript was to identify the contribution to overall tooth loss, by extraction of permanent teeth because of prosthetic treatment reasons. Material and Methods. A cross-sectional study included sex, age, total number of extractions performed by subject, sextant (anterior vs. posterior), group of teeth (incisors, canines, premolars and molars), upper or lower arch, and the main reason underlying extraction (extraction for any reason vs. prosthetic treatment), in patients 18 years of age and older seeking care at a dental school clinic in Mexico. A multivariate logistic regression model was generated. Results. A total of 749 teeth were extracted in 331 patients; 161 teeth (21.5% of total) were extracted for explicit prosthetic treatment indications. As age increased, the likelihood of having an extraction for prosthetic reasons increased 3% (OR = 1.03, p < 0.001). Women (OR = 1.57, p < 0.05) were more likely to be in this situation, and molars (OR = 2.70, p < 0.001) were most at risk. As the total number of extractions increased, the risk of having an extraction for prosthetic reasons decreased (OR = 0.94, p < 0.05). Conclusions. A significant amount (21.5%) of the extractions of permanent teeth were performed for prosthetic reasons in this dental school clinical environment; age, sex, type of tooth, and the total number of extractions moderated

  16. Contribution of prosthetic treatment considerations for dental extractions of permanent teeth

    PubMed Central

    Fernández-Barrera, Miguel Ángel; Casanova-Rosado, Juan Fernando; Mendoza-Rodríguez, Martha; Escoffié-Ramírez, Mauricio; Casanova-Rosado, Alejandro José; Navarrete-Hernández, José de Jesús; Maupomé, Gerardo

    2016-01-01

    Background. Tooth loss is an easily identifiable outcome that summarizes a complex suite of factors in an individual’s history of dental disease and its treatment by dental services over a lifetime. Assessment of overall tooth loss data is essential for epidemiologically evaluating the adequacy of dental care provided at a systems level, as well as for placing in context tooth loss for non-disease causes. For example, when derived from prosthetic treatment planning, the latter may unfortunately lead to some teeth being extracted (pulled) for the sake of better comprehensive clinical results. The objective of the present manuscript was to identify the contribution to overall tooth loss, by extraction of permanent teeth because of prosthetic treatment reasons. Material and Methods. A cross-sectional study included sex, age, total number of extractions performed by subject, sextant (anterior vs. posterior), group of teeth (incisors, canines, premolars and molars), upper or lower arch, and the main reason underlying extraction (extraction for any reason vs. prosthetic treatment), in patients 18 years of age and older seeking care at a dental school clinic in Mexico. A multivariate logistic regression model was generated. Results. A total of 749 teeth were extracted in 331 patients; 161 teeth (21.5% of total) were extracted for explicit prosthetic treatment indications. As age increased, the likelihood of having an extraction for prosthetic reasons increased 3% (OR = 1.03, p < 0.001). Women (OR = 1.57, p < 0.05) were more likely to be in this situation, and molars (OR = 2.70, p < 0.001) were most at risk. As the total number of extractions increased, the risk of having an extraction for prosthetic reasons decreased (OR = 0.94, p < 0.05). Conclusions. A significant amount (21.5%) of the extractions of permanent teeth were performed for prosthetic reasons in this dental school clinical environment; age, sex, type of tooth, and the total number of extractions moderated

  17. Contribution of prosthetic treatment considerations for dental extractions of permanent teeth.

    PubMed

    Fernández-Barrera, Miguel Ángel; Medina-Solís, Carlo Eduardo; Casanova-Rosado, Juan Fernando; Mendoza-Rodríguez, Martha; Escoffié-Ramírez, Mauricio; Casanova-Rosado, Alejandro José; Navarrete-Hernández, José de Jesús; Maupomé, Gerardo

    2016-01-01

    Background. Tooth loss is an easily identifiable outcome that summarizes a complex suite of factors in an individual's history of dental disease and its treatment by dental services over a lifetime. Assessment of overall tooth loss data is essential for epidemiologically evaluating the adequacy of dental care provided at a systems level, as well as for placing in context tooth loss for non-disease causes. For example, when derived from prosthetic treatment planning, the latter may unfortunately lead to some teeth being extracted (pulled) for the sake of better comprehensive clinical results. The objective of the present manuscript was to identify the contribution to overall tooth loss, by extraction of permanent teeth because of prosthetic treatment reasons. Material and Methods. A cross-sectional study included sex, age, total number of extractions performed by subject, sextant (anterior vs. posterior), group of teeth (incisors, canines, premolars and molars), upper or lower arch, and the main reason underlying extraction (extraction for any reason vs. prosthetic treatment), in patients 18 years of age and older seeking care at a dental school clinic in Mexico. A multivariate logistic regression model was generated. Results. A total of 749 teeth were extracted in 331 patients; 161 teeth (21.5% of total) were extracted for explicit prosthetic treatment indications. As age increased, the likelihood of having an extraction for prosthetic reasons increased 3% (OR = 1.03, p < 0.001). Women (OR = 1.57, p < 0.05) were more likely to be in this situation, and molars (OR = 2.70, p < 0.001) were most at risk. As the total number of extractions increased, the risk of having an extraction for prosthetic reasons decreased (OR = 0.94, p < 0.05). Conclusions. A significant amount (21.5%) of the extractions of permanent teeth were performed for prosthetic reasons in this dental school clinical environment; age, sex, type of tooth, and the total number of extractions moderated

  18. Legislation and informed consent brochures for dental patients receiving amalgam restorations.

    PubMed

    Edlich, Richard F; Cochran, Amy A; Cross, Catherine L; Wack, Courtney A; Long, William B; Newkirk, Anthony T

    2008-01-01

    In 2008, Norway banned the use of mercury for amalgam restorations. Four states in the United States have developed Informed Consent Brochures for amalgam restorations that must be given to their dental patients. The authors describe a patient who had a large cavity in his left lower molar tooth no.18 that had to be removed by an oral surgeon. When the patient went to the oral surgeon, the surgeon told the patient that he would replace the carious tooth with a gold implant. He was not given an Informed Consent Brochure regarding dental restorative materials. The oral surgeon extracted the carious tooth, replacing the tooth with a supposed gold crown implant. On his yearly dental examination, his dentist took an x-ray of his dental implant and explained that the x-ray could not distinguish whether the implant contained either gold or mercury. Consequently, the dentist referred him to a dental clinic in which the dental implant could be removed without mercury contamination of the patient's neurologic system during the extraction of the implant from the root canal. During the removal of the dental restoration, the dentist found build up expanding into the root canal that had a black color. The crown and underlying tooth were sent to ALT BioScience for analysis. Elemental analysis of the crown and underlying tooth confirmed the presence of mercury in the restoration. The patient should have been given an Informed Consent Brochure by the dentist that described the dental restoration that was used in the dental implant.

  19. The atraumatic restorative treatment (ART) approach for the management of dental caries.

    PubMed

    Smales, Roger J; Yip, Hak-Kong

    2002-06-01

    There is worldwide interest in and increasing usage of the conservative atraumatic restorative treatment technique or approach for the restoration of primary and permanent teeth. However, most published data on the clinical performance of the newer, high-strength esthetic conventional glass-ionomer restorative cements marketed for the procedure have been derived from short-term studies. There have been very few reports comparing different types of restorative materials and methods of cavity preparation. In primary teeth, after 1 year, success rates have been approximately 80% to 95% for Class I and Class V single-surface restorations, 55% to 75% for Class II multisurface restorations, and 35% to 55% for Class III and Class IV restorations. In permanent teeth, after 2 to 3 years, success rates have been approximately 90% for Class I and Class V single-surface restorations, but little data have been reported for other restoration classes. Failures usually result from restoration losses, fractures, and wear. Further improvements in the design of hand instruments and in the mechanical properties of the newer glass-ionomer cements are required. Currently, use of the atraumatic restorative treatment approach should be restricted to restoration of single-surface caries lesions, especially in permanent teeth, and to sealing of occlusal fissures in selected teeth.

  20. Dental anomalies in the primary dentition and their repetition in the permanent dentition: a diagnostic performance study.

    PubMed

    Marinelli, Andrea; Giuntini, Veronica; Franchi, Lorenzo; Tollaro, Isabella; Baccetti, Tiziano; Defraia, Efisio

    2012-01-01

    This study investigated the recurrence in the permanent dentition of dental anomalies of the primary dentition. A sample of 189 subjects (100 males, 89 females, mean age of 5 years and 7 months) with anomalies of primary teeth (tooth hypodontia, supernumerary teeth, geminated teeth, and fused teeth) was selected and re-analyzed at a mean age of 11 years and 2 months for the recurrence of the dental anomalies in the permanent dentition. As a control group, 271 subjects (123 males, 148 females) without dental anomalies in the primary dentition were selected. The recurrence in the permanent dentition of the dental anomalies in the primary dentition was evaluated by measures of diagnostic performance. The results showed high values for the repetition of hypodontia (positive likelihood ratio = 102.0); low score for the repetition of hyperdontia (positive likelihood ratio = 6.5); low positive likelihood ratio (9.1) for gemination of primary teeth resulting in supernumerary permanent teeth; high positive likelihood ratio (47.0) for fusion of primary teeth followed by missing permanent teeth. Dental anomalies in the primary dentition are associated with an increased likelihood of anomalies of the succedaneous permanent.

  1. Genome-wide association Scan of dental caries in the permanent dentition

    PubMed Central

    2012-01-01

    Background Over 90% of adults aged 20 years or older with permanent teeth have suffered from dental caries leading to pain, infection, or even tooth loss. Although caries prevalence has decreased over the past decade, there are still about 23% of dentate adults who have untreated carious lesions in the US. Dental caries is a complex disorder affected by both individual susceptibility and environmental factors. Approximately 35-55% of caries phenotypic variation in the permanent dentition is attributable to genes, though few specific caries genes have been identified. Therefore, we conducted the first genome-wide association study (GWAS) to identify genes affecting susceptibility to caries in adults. Methods Five independent cohorts were included in this study, totaling more than 7000 participants. For each participant, dental caries was assessed and genetic markers (single nucleotide polymorphisms, SNPs) were genotyped or imputed across the entire genome. Due to the heterogeneity among the five cohorts regarding age, genotyping platform, quality of dental caries assessment, and study design, we first conducted genome-wide association (GWA) analyses on each of the five independent cohorts separately. We then performed three meta-analyses to combine results for: (i) the comparatively younger, Appalachian cohorts (N = 1483) with well-assessed caries phenotype, (ii) the comparatively older, non-Appalachian cohorts (N = 5960) with inferior caries phenotypes, and (iii) all five cohorts (N = 7443). Top ranking genetic loci within and across meta-analyses were scrutinized for biologically plausible roles on caries. Results Different sets of genes were nominated across the three meta-analyses, especially between the younger and older age cohorts. In general, we identified several suggestive loci (P-value ≤ 10E-05) within or near genes with plausible biological roles for dental caries, including RPS6KA2 and PTK2B, involved in p38-depenedent MAPK signaling

  2. Understanding dental CAD/CAM for restorations--the digital workflow from a mechanical engineering viewpoint.

    PubMed

    Tapie, L; Lebon, N; Mawussi, B; Fron Chabouis, H; Duret, F; Attal, J-P

    2015-01-01

    As digital technology infiltrates every area of daily life, including the field of medicine, so it is increasingly being introduced into dental practice. Apart from chairside practice, computer-aided design/computer-aided manufacturing (CAD/CAM) solutions are available for creating inlays, crowns, fixed partial dentures (FPDs), implant abutments, and other dental prostheses. CAD/CAM dental solutions can be considered a chain of digital devices and software for the almost automatic design and creation of dental restorations. However, dentists who want to use the technology often do not have the time or knowledge to understand it. A basic knowledge of the CAD/CAM digital workflow for dental restorations can help dentists to grasp the technology and purchase a CAM/CAM system that meets the needs of their office. This article provides a computer-science and mechanical-engineering approach to the CAD/CAM digital workflow to help dentists understand the technology.

  3. Understanding dental CAD/CAM for restorations--the digital workflow from a mechanical engineering viewpoint.

    PubMed

    Tapie, L; Lebon, N; Mawussi, B; Fron Chabouis, H; Duret, F; Attal, J-P

    2015-01-01

    As digital technology infiltrates every area of daily life, including the field of medicine, so it is increasingly being introduced into dental practice. Apart from chairside practice, computer-aided design/computer-aided manufacturing (CAD/CAM) solutions are available for creating inlays, crowns, fixed partial dentures (FPDs), implant abutments, and other dental prostheses. CAD/CAM dental solutions can be considered a chain of digital devices and software for the almost automatic design and creation of dental restorations. However, dentists who want to use the technology often do not have the time or knowledge to understand it. A basic knowledge of the CAD/CAM digital workflow for dental restorations can help dentists to grasp the technology and purchase a CAM/CAM system that meets the needs of their office. This article provides a computer-science and mechanical-engineering approach to the CAD/CAM digital workflow to help dentists understand the technology. PMID:25911827

  4. Thermal-lens study of semiconductor nanoparticles embedded in restorative dental resin

    NASA Astrophysics Data System (ADS)

    Alves, Leandro P.; Pilla, Viviane; Iwazaki, Adalberto N.; Barja, Paulo R.; Munin, Egberto

    2013-02-01

    Thermal Lens (TL) and spectroscopic characterizations were performed in CdSe/ZnS core-shell quantum dots (QDs) embedded into two commercial dental resin composites. The thermal-optical studies were performed in CdSe/ZnS QDs (core size Φ= 4.1 nm) and PMMA-encapsulated CdSe/ZnS (Φ= 3.7 nm) embedded in restorative dental resins at concentration of 0.025 and 0.42 % in mass, respectively. The thermal diffusivity (D) results are characteristics of the dental resin composites studied. Photoacoustic (PA) technique results for the dental resin composites support the TL results.

  5. Complex layered dental restorations: Are they recognizable and do they survive extreme conditions?

    PubMed

    Soon, Alistair S; Bush, Mary A; Bush, Peter J

    2015-09-01

    Recent research has shown that restorative dental materials can be recognized by microscopy and elemental analysis (scanning electron microscopy/energy dispersive X-ray spectroscopy and X-ray fluorescence; SEM/EDS and XRF) and that this is possible even in extreme conditions, such as cremation. These analytical methods and databases of dental materials properties have proven useful in DVI (disaster victim identification) of a commercial plane crash in 2009, and in a number of other victim identification cases. Dental materials appear on the market with ever expanding frequency. With their advent, newer methods of restoration have been proposed and adopted in the dental office. Methods might include placing multiple layers of dental materials, where they have different properties including adhesion, viscosity, or working time. These different dental materials include filled adhesives, flowable resins, glass ionomer cements, composite resins, liners and sealants. With possible combinations of different materials in these restorations, the forensic odontologist is now confronted with a new difficulty; how to recognize each individual material. The question might be posed if it is even possible to perform this task. Furthermore, an odontologist might be called upon to identify a victim under difficult circumstances, such as when presented with fragmented or incinerated remains. In these circumstances the ability to identify specific dental materials could assist in the identification of the deceased. Key to use of this information is whether these new materials and methods are detailed in the dental chart. Visual or radiographic inspection may not reveal the presence of a restoration, let alone the possible complex nature of that restoration. This study demonstrates another scientific method in forensic dental identification. PMID:26151675

  6. Complex layered dental restorations: Are they recognizable and do they survive extreme conditions?

    PubMed

    Soon, Alistair S; Bush, Mary A; Bush, Peter J

    2015-09-01

    Recent research has shown that restorative dental materials can be recognized by microscopy and elemental analysis (scanning electron microscopy/energy dispersive X-ray spectroscopy and X-ray fluorescence; SEM/EDS and XRF) and that this is possible even in extreme conditions, such as cremation. These analytical methods and databases of dental materials properties have proven useful in DVI (disaster victim identification) of a commercial plane crash in 2009, and in a number of other victim identification cases. Dental materials appear on the market with ever expanding frequency. With their advent, newer methods of restoration have been proposed and adopted in the dental office. Methods might include placing multiple layers of dental materials, where they have different properties including adhesion, viscosity, or working time. These different dental materials include filled adhesives, flowable resins, glass ionomer cements, composite resins, liners and sealants. With possible combinations of different materials in these restorations, the forensic odontologist is now confronted with a new difficulty; how to recognize each individual material. The question might be posed if it is even possible to perform this task. Furthermore, an odontologist might be called upon to identify a victim under difficult circumstances, such as when presented with fragmented or incinerated remains. In these circumstances the ability to identify specific dental materials could assist in the identification of the deceased. Key to use of this information is whether these new materials and methods are detailed in the dental chart. Visual or radiographic inspection may not reveal the presence of a restoration, let alone the possible complex nature of that restoration. This study demonstrates another scientific method in forensic dental identification.

  7. Urinary levels of nickel and chromium associated with dental restoration by nickel–chromium based alloys

    PubMed Central

    Chen, Bo; Xia, Gang; Cao, Xin-Ming; Wang, Jue; Xu, Bi-Yao; Huang, Pu; Chen, Yue; Jiang, Qing-Wu

    2013-01-01

    This paper aims to investigate if the dental restoration of nickel–chromium based alloy (Ni–Cr) leads to the enhanced excretions of Ni and Cr in urine. Seven hundred and ninety-five patients in a dental hospital had single or multiple Ni–Cr alloy restoration recently and 198 controls were recruited to collect information on dental restoration by questionnaire and clinical examination. Urinary concentrations of Ni and Cr from each subject were measure by graphite furnace atomic absorption spectrometry. Compared to the control group, the urinary level of Ni was significantly higher in the patient group of <1 month of the restoration duration, among which higher Ni excretions were found in those with either a higher number of teeth replaced by dental alloys or a higher index of metal crown not covered with the porcelain. Urinary levels of Cr were significantly higher in the three patient groups of <1, 1 to <3 and 3 to <6 months, especially in those with a higher metal crown exposure index. Linear curve estimations showed better relationships between urinary Ni and Cr in patients within 6-month groups. Our data suggested significant increased excretions of urinary Ni and Cr after dental restoration. Potential short- and long-term effects of Ni–Cr alloy restoration need to be investigated. PMID:23579466

  8. Urinary levels of nickel and chromium associated with dental restoration by nickel-chromium based alloys.

    PubMed

    Chen, Bo; Xia, Gang; Cao, Xin-Ming; Wang, Jue; Xu, Bi-Yao; Huang, Pu; Chen, Yue; Jiang, Qing-Wu

    2013-03-01

    This paper aims to investigate if the dental restoration of nickel-chromium based alloy (Ni-Cr) leads to the enhanced excretions of Ni and Cr in urine. Seven hundred and ninety-five patients in a dental hospital had single or multiple Ni-Cr alloy restoration recently and 198 controls were recruited to collect information on dental restoration by questionnaire and clinical examination. Urinary concentrations of Ni and Cr from each subject were measure by graphite furnace atomic absorption spectrometry. Compared to the control group, the urinary level of Ni was significantly higher in the patient group of <1 month of the restoration duration, among which higher Ni excretions were found in those with either a higher number of teeth replaced by dental alloys or a higher index of metal crown not covered with the porcelain. Urinary levels of Cr were significantly higher in the three patient groups of <1, 1 to <3 and 3 to <6 months, especially in those with a higher metal crown exposure index. Linear curve estimations showed better relationships between urinary Ni and Cr in patients within 6-month groups. Our data suggested significant increased excretions of urinary Ni and Cr after dental restoration. Potential short- and long-term effects of Ni-Cr alloy restoration need to be investigated.

  9. Teaching the placement of posterior resin-based composite restorations in Spanish dental schools

    PubMed Central

    Lynch, Christopher; McConnell, Robert; Wilson, Nairn

    2012-01-01

    Objectives: In an area of esthetic dentistry such as posterior composites, in which new materials and techniques are being devolved continuously, it is important to confirm that dental students have a clear understanding of the basic principles of clinical application of this knowledge. Considering that the preparation of dental graduates in Spain may be of interest to competent dental authorities and employers with whom they can work worldwide, this study investigated the teaching of posterior composite restorations in Spanish dental schools. Study design: In late 2009⁄ early 2010, a questionnaire seeking information on the teaching of posterior composites was emailed to the professor responsible for teaching operative dentistry in each of the fifteen dental schools having complete undergraduate dental degree programs in Spain. Results: The response rate was 100%. Most investigated topics did not show noteworthy differences depending on whether the schools were public or private. Variations were found among Spanish dental schools in both the amount and content of the teaching programs concerning posterior composite restorations. Differences were recorded in the teaching of cavity design, contraindications to composite placement, indications for liners and bases, matrix and wedging techniques, composite and bonding systems, light curing and finishing procedures for composite restorations. More consistency was observed in teaching methods of moisture-control, indirect composites and amalgam bonding. Conclusions: As recommended in previously surveyed countries, efforts must be made to promote harmonization of dental curricula to make it easier for graduates to work elsewhere, and to ensure they meet the needs of their patients on entering independent practice. Key words:Aesthetic dentistry, composite restoration, dental education, teaching program, undergraduate dental student. PMID:22322491

  10. The history and clinical application of a chairside CAD/CAM dental restoration system.

    PubMed

    Stutes, Richard D

    2006-10-01

    Since its introduction by Sirona Dental Systems (Charlotte, North Carolina, USA and Bensheim, Germany) in 1985, the CEREC Chairside CAD/CAM restoration system has steadily earned a loyal following among dentists. This article describes the history and evolution of the CEREC System, its clinical application and treatment modality, the restorative materials used to fabricate the restorations and an overview of clinical findings regarding the in vivo performance of the materials.

  11. Dental age estimation in Japanese individuals combining permanent teeth and third molars.

    PubMed

    Ramanan, Namratha; Thevissen, Patrick; Fleuws, Steffen; Willems, G

    2012-12-01

    The study aim was, firstly, to verify the Willems et al. model on a Japanese reference sample. Secondly to develop a Japanese reference model based on the Willems et al. method and to verify it. Thirdly to analyze the age prediction performance adding tooth development information of third molars to permanent teeth. Retrospectively 1877 panoramic radiographs were selected in the age range between 1 and 23 years (1248 children, 629 sub-adults). Dental development was registered applying Demirjian 's stages of the mandibular left permanent teeth in children and Köhler stages on the third molars. The children's data were, firstly, used to validate the Willems et al. model (developed a Belgian reference sample), secondly, split ino a training and a test sample. On the training sample a Japanese reference model was developed based on the Willems method. The developed model and the Willems et al; model were verified on the test sample. Regression analysis was used to detect the age prediction performance adding third molar scores to permanent tooth scores. The validated Willems et al. model provided a mean absolute error of 0.85 and 0.75 years in females and males, respectively. The mean absolute error in the verified Willems et al. and the developed Japanese reference model was 0.85, 0.77 and 0.79, 0.75 years in females and males, respectively. On average a negligible change in root mean square error values was detected adding third molar scores to permanent teeth scores. The Belgian sample could be used as a reference model to estimate the age of the Japanese individuals. Combining information from the third molars and permanent teeth was not providing clinically significant improvement of age predictions based on permanent teeth information alone. PMID:23474507

  12. Dental age estimation in Japanese individuals combining permanent teeth and third molars.

    PubMed

    Ramanan, Namratha; Thevissen, Patrick; Fleuws, Steffen; Willems, G

    2012-12-01

    The study aim was, firstly, to verify the Willems et al. model on a Japanese reference sample. Secondly to develop a Japanese reference model based on the Willems et al. method and to verify it. Thirdly to analyze the age prediction performance adding tooth development information of third molars to permanent teeth. Retrospectively 1877 panoramic radiographs were selected in the age range between 1 and 23 years (1248 children, 629 sub-adults). Dental development was registered applying Demirjian 's stages of the mandibular left permanent teeth in children and Köhler stages on the third molars. The children's data were, firstly, used to validate the Willems et al. model (developed a Belgian reference sample), secondly, split ino a training and a test sample. On the training sample a Japanese reference model was developed based on the Willems method. The developed model and the Willems et al; model were verified on the test sample. Regression analysis was used to detect the age prediction performance adding third molar scores to permanent tooth scores. The validated Willems et al. model provided a mean absolute error of 0.85 and 0.75 years in females and males, respectively. The mean absolute error in the verified Willems et al. and the developed Japanese reference model was 0.85, 0.77 and 0.79, 0.75 years in females and males, respectively. On average a negligible change in root mean square error values was detected adding third molar scores to permanent teeth scores. The Belgian sample could be used as a reference model to estimate the age of the Japanese individuals. Combining information from the third molars and permanent teeth was not providing clinically significant improvement of age predictions based on permanent teeth information alone.

  13. Knowledge and practice of implant-retained restorations among dental students in Saudi Arabia

    PubMed Central

    Vohra, Fahim; Shah, Altaf Hussain; Zafar, Mohammad Sohail; Kola, Zaheer

    2015-01-01

    Objectives: The aim of the study was to assess the knowledge and practice of implant retained restorations (IRR) among senior dental students in Saudi Arabia. Methods: Four hundred questionnaires were distributed among senior dental students of five dental schools in Saudi Arabia. Student’s knowledge was assessed regarding which implant restoration [cement retained restoration (CRR) or screw retained restoration (SRR)] better provides the desired clinical properties. Students’ practice of IRR, perception of their knowledge and need for further education related to IRR were also assessed. Descriptive statistics and chi-square test were employed to assess collected data. Results: Three hundred and fifty four senior dental students responded at a response rate of 88.5%. Thirty three percent respondents did not have any practical experience of IRR. Students showed a clear preference for CRR with regards to aesthetics (71.4%), passive fit (55.3%), fabrication ease (57.3%) and fracture resistance (40%). SRR were considered to provide better retention (59.6%), soft tissue health (51.1%) and ease of retrievability (72%). Nearly 40% of students agreed that they did not get sufficient information related to IRR in undergraduate courses. Conclusions: Clinical training of IRR is compromised in the undergraduate curriculum in dental schools of Saudi Arabia. The knowledge of dental students regarding IRR was broadly in line with current evidence. PMID:26430416

  14. Synchrotron-radiation-based X-ray micro-computed tomography reveals dental bur debris under dental composite restorations.

    PubMed

    Hedayat, Assem; Nagy, Nicole; Packota, Garnet; Monteith, Judy; Allen, Darcy; Wysokinski, Tomasz; Zhu, Ning

    2016-05-01

    Dental burs are used extensively in dentistry to mechanically prepare tooth structures for restorations (fillings), yet little has been reported on the bur debris left behind in the teeth, and whether it poses potential health risks to patients. Here it is aimed to image dental bur debris under dental fillings, and allude to the potential health hazards that can be caused by this debris when left in direct contact with the biological surroundings, specifically when the debris is made of a non-biocompatible material. Non-destructive micro-computed tomography using the BioMedical Imaging & Therapy facility 05ID-2 beamline at the Canadian Light Source was pursued at 50 keV and at a pixel size of 4 µm to image dental bur fragments under a composite resin dental filling. The bur's cutting edges that produced the fragment were also chemically analyzed. The technique revealed dental bur fragments of different sizes in different locations on the floor of the prepared surface of the teeth and under the filling, which places them in direct contact with the dentinal tubules and the dentinal fluid circulating within them. Dispersive X-ray spectroscopy elemental analysis of the dental bur edges revealed that the fragments are made of tungsten carbide-cobalt, which is bio-incompatible.

  15. Fractographic features of glass-ceramic and zirconia-based dental restorations fractured during clinical function.

    PubMed

    Oilo, Marit; Hardang, Anne D; Ulsund, Amanda H; Gjerdet, Nils R

    2014-06-01

    Fractures during clinical function have been reported as the major concern associated with all-ceramic dental restorations. The aim of this study was to analyze the fracture features of glass-ceramic and zirconia-based restorations fractured during clinical use. Twenty-seven crowns and onlays were supplied by dentists and dental technicians with information about type of cement and time in function, if available. Fourteen lithium disilicate glass-ceramic restorations and 13 zirconia-based restorations were retrieved and analyzed. Fractographic features were examined using optical microscopy to determine crack initiation and crack propagation of the restorations. The material comprised fractured restorations from one canine, 10 incisors, four premolars, and 11 molars. One crown was not categorized because of difficulty in orientation of the fragments. The results revealed that all core and veneer fractures initiated in the cervical margin and usually from the approximal area close to the most coronally placed curvature of the margin. Three cases of occlusal chipping were found. The margin of dental all-ceramic single-tooth restorations was the area of fracture origin. The fracture features were similar for zirconia, glass-ceramic, and alumina single-tooth restorations. Design features seem to be of great importance for fracture initiation.

  16. Fractographic features of glass-ceramic and zirconia-based dental restorations fractured during clinical function

    PubMed Central

    Øilo, Marit; Hardang, Anne D; Ulsund, Amanda H; Gjerdet, Nils R

    2014-01-01

    Fractures during clinical function have been reported as the major concern associated with all-ceramic dental restorations. The aim of this study was to analyze the fracture features of glass-ceramic and zirconia-based restorations fractured during clinical use. Twenty-seven crowns and onlays were supplied by dentists and dental technicians with information about type of cement and time in function, if available. Fourteen lithium disilicate glass-ceramic restorations and 13 zirconia-based restorations were retrieved and analyzed. Fractographic features were examined using optical microscopy to determine crack initiation and crack propagation of the restorations. The material comprised fractured restorations from one canine, 10 incisors, four premolars, and 11 molars. One crown was not categorized because of difficulty in orientation of the fragments. The results revealed that all core and veneer fractures initiated in the cervical margin and usually from the approximal area close to the most coronally placed curvature of the margin. Three cases of occlusal chipping were found. The margin of dental all-ceramic single-tooth restorations was the area of fracture origin. The fracture features were similar for zirconia, glass-ceramic, and alumina single-tooth restorations. Design features seem to be of great importance for fracture initiation. PMID:24698173

  17. Does atraumatic restorative treatment reduce dental anxiety in children? A systematic review and meta-analysis

    PubMed Central

    Simon, Arun K.; Bhumika, T. V.; Nair, N. Sreekumaran

    2015-01-01

    Dental anxiety is one of the major problems affecting children, which impairs the rendering of dental care, leading to impaired quality of life. It often leads to occupational stress in dental personnel and conflict between parents/caregivers. The objective of this study was to conduct a systematic review and meta-analysis of randomized controlled trials done in children, to synthesize evidence of the effectiveness of atraumatic restorative treatment (ART) in reducing dental anxiety in children compared to conventional restorative treatments. The databases searched included PubMed, Google Scholar and The Cochrane Oral Health Group's Trials Register. Eligible studies reporting dental anxiety by a variety of psychometric scales were tabulated. The review was conducted and reported in accordance with the guidelines provided by the Cochrane Collaboration. Among 416 studies retrieved through literature search, six studies matched the inclusion criteria. Due to lack of data, only three studies were included for meta-analysis using RevMan software (Review Manager, Version 5.3;The Cochrane Collaboration, Copenhagen, 2014). The pooled meta-analysis data, (standardized mean difference − 2.12 [95% confidence interval: −4.52, 0.27]) failed to show any difference between ART group and the conventional treatment group. In conclusion, ART was not more beneficial in reducing dental anxiety among pediatric dental patients. The findings are relevant in the field of clinical practice in dentistry in the management of the anxious pediatric dental patient. PMID:26038668

  18. Amino acid derivative-mediated detoxification and functionalization of dual cure dental restorative material for dental pulp cell mineralization.

    PubMed

    Minamikawa, Hajime; Yamada, Masahiro; Iwasa, Fuminori; Ueno, Takeshi; Deyama, Yoshiaki; Suzuki, Kuniaki; Yawaka, Yasutaka; Ogawa, Takahiro

    2010-10-01

    Current dental restorative materials are only used to fill the defect of hard tissues, such as dentin and enamel, because of their cytotoxicity. Therefore, exposed dental pulp tissues in deep cavities must be first covered by a pulp capping material like calcium hydroxide to form a layer of mineralized tissue. However, this tissue mineralization is based on pathological reaction and triggers long-lasting inflammation, often causing clinical problems. This study tested the ability of N-acetyl cysteine (NAC), amino acid derivative, to reduce cytotoxicity and induce mineralized tissue conductivity in resin-modified glass ionomer (RMGI), a widely used dental restorative material having dual cure mechanism. Rat dental pulp cells were cultured on untreated or NAC-supplemented RMGI. NAC supplementation substantially increased the percentage of viable cells from 46.7 to 73.3% after 24-h incubation. Cell attachment, spreading, proliferative activity, and odontoblast-related gene and protein expressions increased significantly on NAC-supplemented RMGI. The mineralization capability of cells, which was nearly suppressed on untreated RMGI, was induced on NAC-supplemented RMGI. These improved behaviors and functions of dental pulp cells on NAC-supplemented RMGI were associated with a considerable reduction in the production of intracellular reactive oxygen species and with the increased level of intracellular glutathione reserves. These results demonstrated that NAC could detoxify and functionalize RMGIs via two different mechanisms involving in situ material detoxification and antioxidant cell protection. We believe that this study provides a new approach for developing dental restorative materials that enables mineralized tissue regeneration.

  19. Functional results of dental restoration with osseointegrated implants after mandible reconstruction.

    PubMed

    Gürlek, A; Miller, M J; Jacob, R F; Lively, J A; Schusterman, M A

    1998-03-01

    We reviewed the cases of 20 cancer patients (mean age 47.4 years) in whom osseointegrated implants were used for dental restoration after mandibular reconstruction between January of 1988 and December of 1994. Seventy-one implants were placed into bone flaps (n = 60) or native mandible (n = 11), an average of 3.55 per patient (range, 2 to 5). Successful integration occurred in 91.5 percent (65 of 71); there were five early failures and one late failure, with no significant difference between the number lost in microvascular flaps (5 of 60) and native mandible (1 of 11) (as determined by Fisher's exact test). Functional evaluation included assessments of diet, speech, and cosmesis. Based on our review, we concluded that (1) implants enhance dental restoration in selected patients, and (2) microvascular bone flaps, including the fibula and iliac crest, are well suited for dental implant restoration.

  20. Stress management for dental students performing their first pediatric restorative procedure.

    PubMed

    Piazza-Waggoner, Carrie A; Cohen, Lindsey L; Kohli, Kavita; Taylor, Brandie K

    2003-05-01

    Research has demonstrated that dental students experience considerable stress during their training. Students' anxiety is likely to be especially high when they perform their first pediatric restorative procedure. The aims of this study were to provide a description of dental students' level of anxiety and typical coping strategies and to evaluate the use of a distress management intervention for reducing anxiety around their first pediatric restorative procedure. Dental students were randomly assigned to either an Anxiety Management or an Attention Control group. The management group received training on relaxation strategies (i.e., deep breathing, progressive muscle relaxation). The control group attended a lecture on the relation among stress, anxiety, and health. No significant differences were found between group levels of anxiety related to their first pediatric restorative procedure. Information is provided on students' reported level of anxiety and general coping strategies. Limitations of the current study and suggestions for future research are provided.

  1. Knowledge and Attitudes of General Dental Practitioners Towards Posterior Composite Restorations in Northern Saudi Arabia

    PubMed Central

    2015-01-01

    Introduction: The restoration of posterior teeth with composite restoration is a common clinical practice nowadays. Opinions regarding posterior composite restorations vary among dentists. The aim of the present study was to determine the knowledge and opinions of general dental practitioners towards composite resins for posterior teeth restorations. Materials and Methods: A questionnaire was devised to elicit information regarding placement of composite restoration in posterior teeth in northern Saudi Arabia. It was distributed to 230 dentists by hand and e-mail. A response rate 136 (59%) was obtained. The questionnaire sought details about case selection criteria for composite restoration, problems associated with composites and reasons for selecting composite restoration in posterior teeth. The data was processed and analysed by SPSS statistical software 19. Frequencies and percentages were calculated for various responses of the participants. Results: Regarding the selection of composite restoration in posterior teeth, 97% of the dentists did not prefer composite placement for class I restoration with heavy occlusal contacts. 83% of the participants did not select composite for class II restoration. 78% of the respondents opted for restoring composites in small defects. Patients’ aesthetic demands (90%), amalgam replacement (22%) and restoration of endodontically treated teeth (42%) were the contributing factors. Regarding the problems associated with posterior composite restorations. Recurrent caries (87%), post-operative sensitivity (84%), restoration fracture (83%) and polymerization shrinkage (73%) were the major problems reported by respondents associated with composite restorations. The other minor concerns were wear (60%), contact build up in case of class II cavity restorations (51%) and isolation for composite restorations (36%). Conservative cavity preparation (78%), aesthetics (73%) and patient preference (65%) were the main reasons for choosing

  2. Classifying dental ceramics: numerous materials and formulations available for indirect restorations.

    PubMed

    Helvey, Gregg A

    2014-01-01

    Because there are numerous ceramic systems available to clinicians for all types of indirect restorations, deciding which system works best for a given clinical situation can be a challenge. Understanding the different classifications of ceramic restoratives can be helpful not only to the clinician but also the dental technician. Manufacturers are constantly introducing newer ceramic materials and improving their existing systems, which has resulted in an increase in all-ceramic restorations and fewer porcelain-to-metal restorations. The classification of ceramic materials remains mostly constant; however, it is subject to change based on newer materials and formulations. The classifications of ceramics are described using several different methods.

  3. Understanding dental CAD/CAM for restorations--accuracy from a mechanical engineering viewpoint.

    PubMed

    Tapie, Laurent; Lebon, Nicolas; Mawussi, Bernardin; Fron-Chabouis, Hélène; Duret, Francois; Attal, Jean-Pierre

    2015-01-01

    As is the case in the field of medicine, as well as in most areas of daily life, digital technology is increasingly being introduced into dental practice. Computer-aided design/ computer-aided manufacturing (CAD/CAM) solutions are available not only for chairside practice but also for creating inlays, crowns, fixed partial dentures (FPDs), implant abutments, and other dental prostheses. CAD/CAM dental practice can be considered as the handling of devices and software processing for the almost automatic design and creation of dental restorations. However, dentists who want to use dental CAD/CAM systems often do not have enough information to understand the variations offered by such technology practice. Knowledge of the random and systematic errors in accuracy with CAD/CAM systems can help to achieve successful restorations with this technology, and help with the purchasing of a CAD/CAM system that meets the clinical needs of restoration. This article provides a mechanical engineering viewpoint of the accuracy of CAD/ CAM systems, to help dentists understand the impact of this technology on restoration accuracy. PMID:26734668

  4. Fluoride release and recharge abilities of contemporary fluoride-containing restorative materials and dental adhesives.

    PubMed

    Dionysopoulos, Dimitrios; Koliniotou-Koumpia, Eugenia; Helvatzoglou-Antoniades, Maria; Kotsanos, Nikolaos

    2013-01-01

    The aim of this study was to evaluate the fluoride release of five fluoride-releasing restorative materials and three dental adhesives, before and after NaF solution treatment. Five restorative materials (Fuji IX GP, GC Corp.; Ketac N100, 3M ESPE; Dyract Extra, Dentsply; Beautifil II, Shofu Inc.; Wave, SDI) and three dental adhesives (Stae, SDI; Fluorobond II - Shofu Inc.; Prime & Bond NT, Dentsply) were investigated before and after NaF solution treatment. A fluoride ion-selective electrode was to measure fluoride concentrations. During the 86-day period before NaF solution treatment, Fuji IX GP released the highest amount of fluoride among the restorative materials while Prime & Bond NT was the highest among the dental adhesives. After NaF solution treatment, Fuji IX GP again ranked the highest in fluoride release among the restorative materials while Fluorobond II ranked the highest among dental adhesives. It was concluded that the compositions and setting mechanisms of fluoride-containing dental materials influenced their fluoride release and recharge abilities.

  5. Understanding dental CAD/CAM for restorations--accuracy from a mechanical engineering viewpoint.

    PubMed

    Tapie, Laurent; Lebon, Nicolas; Mawussi, Bernardin; Fron-Chabouis, Hélène; Duret, Francois; Attal, Jean-Pierre

    2015-01-01

    As is the case in the field of medicine, as well as in most areas of daily life, digital technology is increasingly being introduced into dental practice. Computer-aided design/ computer-aided manufacturing (CAD/CAM) solutions are available not only for chairside practice but also for creating inlays, crowns, fixed partial dentures (FPDs), implant abutments, and other dental prostheses. CAD/CAM dental practice can be considered as the handling of devices and software processing for the almost automatic design and creation of dental restorations. However, dentists who want to use dental CAD/CAM systems often do not have enough information to understand the variations offered by such technology practice. Knowledge of the random and systematic errors in accuracy with CAD/CAM systems can help to achieve successful restorations with this technology, and help with the purchasing of a CAD/CAM system that meets the clinical needs of restoration. This article provides a mechanical engineering viewpoint of the accuracy of CAD/ CAM systems, to help dentists understand the impact of this technology on restoration accuracy.

  6. Optical coherence tomography and confocal microscopy investigations of dental structures and restoration materials

    NASA Astrophysics Data System (ADS)

    Negrutiu, Meda L.; Sinescu, Cosmin; Rominu, Mihai; Hughes, Michael; Dobre, George; Podoleanu, Adrian G.

    2009-02-01

    Nowadays, optical tomographic techniques are of particular importance in the medical imaging field, because these techniques can provide non-invasive diagnostic images. The present study evaluates the potential of en-face optical coherence tomography (OCT) as a possible non-invasive high resolution imaging method in supplying the necessary information on the quality of dental hard tissues and defects of dental restorative materials. Teeth after several treatment methods are imaged in order to asses the material defects and micro-leakage of tooth-filling interface as well as to evaluate the quality of dental hard tissue. C-scan and B-scan OCT images as well as confocal images are acquired from a large range of samples. Cracks and voids in the dental structures as well as gaps between the dental interfaces and material defects are clearly exposed. The advantages of the OCT method consist in non-invasiveness and high resolution.

  7. Optimal restoration of dental esthetics and function with advanced implant-supported prostheses: a clinical report.

    PubMed

    Meulen, Peter van der; Linden, Wynand van der; Eeden, Ronnie van

    2012-07-01

    For more than 25 years, computer-aided design and computer-aided manufacturing (CAD/CAM) technology has been used in implant restorative dentistry. Today this technology offers a means of milling titanium frameworks that fit dental implants accurately. This report presents a restoratively driven protocol employing advanced implant restorative and surgical techniques. Treatment of a patient with advanced periodontitis with extensive loss of hard and soft tissues is presented. After extraction of the patient's remaining hopeless teeth, dental implants were placed, along with interim, fixed-margin abutments and abutment protection caps. Two days later, acrylic resin fixed-interim prostheses restored the patient's esthetics and partial masticatory function. After implant osseointegration, maxillary, and mandibular frameworks for definitive prostheses were milled from Ti alloy, using one specific CAD/CAM technology. The benefits of this technology are also discussed.

  8. Informatics systems to assess and apply clinical research on dental restorative materials.

    PubMed

    Anusavice, K J

    2003-12-01

    Dental biomaterials are used clinically for one or more of the following purposes: to restore function, to enhance esthetics, and to prevent or arrest demineralization of tooth structure. Studies of the clinical performance of restorations and prostheses made from these materials have generally focused on quality assessment and survival statistics. Data from these studies should provide probabilities of specific treatment outcomes that are useful for practicing dentists. However, the utility of these data is limited by the lack of national and international standards for assessing these clinical outcomes. Standardized approaches toward clinical informatics and treatment-decision analysis are urgently needed to minimize the variability of clinical outcomes reported in publications associated with direct and indirect restorative materials used for dental restorations and prostheses.

  9. Esthetic techniques and restorative systems used in the second-year undergraduate dental curriculum.

    PubMed

    Raigrodski, Ariel J; Harrison, James D

    2003-01-01

    Metal-free tooth-colored restorative systems for fabricating indirect intracoronal and extracoronal restorations have been developed because of patients' demand for superior esthetics. During the past decade, long-term clinical studies have demonstrated the success of many of these types of restorations in terms of function and esthetics. Ceramic veneers, all-ceramic crowns, ceramic onlays, and composite-resin inlays are becoming an integral part of contemporary clinical practice. The constant evolution in bonding techniques, adhesive systems, and cements plays a major role in the success of these metal-free restorations. In addition, home-bleaching procedures have become an integral part of the esthetically oriented dental practice. This article discusses the rationale, scientific basis, and implementation of a new undergraduate preclinical esthetics course for second-year dental students at the Louisiana State University Health Sciences Center School of Dentistry.

  10. Practitioner, patient, and caries lesion characteristics associated with type of material used to restore carious teeth: findings from The Dental PBRN

    PubMed Central

    Makhija, Sonia K; Gordan, Valeria V.; Gilbert, Gregg H.; Litaker, Mark S.; Rindal, D. Brad; Pihlstrom, Daniel J.; Qvist, Vibeke

    2011-01-01

    Background The authors conducted a study to identify factors associated with material use by dentists in The Dental Practice-Based Research Network (DPBRN) when placing the first restoration on permanent tooth surfaces. Methods A total of 182 DPBRN practitioner-investigators provided data on 5,599 posterior teeth with caries. Practitioner-investigators completed an enrollment questionnaire that included the dentist’s age, gender, practice workload, practice type, and years since graduation. When a consented patient presented with a previously un-restored carious surface, practitioner-investigators recorded patient and tooth characteristics. Results Amalgam was used more often than direct resin-based composite (RBC) for posterior carious lesions. Practitioner/practice characteristics (years since graduation and type of practice); patient characteristics (gender, race, age, and dental insurance); and lesion characteristics (tooth location and surface, pre-and post-operative depth) were associated with the type of restorative material used. Conclusions There are several practitioner/practice, patient, and lesion characteristics significantly associated with use of amalgam and RBC: region, years since graduation, dental insurance, tooth location and surface, and pre-and post-operative depth. Clinical implications Amalgam remains a material commonly used by United States dentists to restore posterior caries lesions. PMID:21628683

  11. Study on the Levitation and Restoring Force Characteristics of the Improved HTS-permanent Magnet Hybrid Magnetic Bearing

    NASA Astrophysics Data System (ADS)

    Sugiyama, R.; Oguni, K.; Ohashi, S.

    We have developed the hybrid magnetic bearing using permanent magnets and high temperature bulk super conductor (HTS). In this system, the permanent magnet has ring type structure so that the permanent magnet and the HTS can be set to the stator. The pinning force of the HTS is used for the levitation and the guidance. Repulsive force of the permanent magnets was used in the conventional hybrid system. However the restoring force in the guidance direction of the conventional hybrid system decreases by the side slip force of the permanent magnets. In this research, attractive force of permanent magnets is used for increasing the load weight in the guidance direction. In this paper, influence of the hybrid system on the static characteristics of the rotor is studied. Three-dimensional numerical analysis of the linkage flux (in the levitation and the guidance direction) in the HTS is undertaken. The stator side permanent magnet increases the linkage flux of the levitation direction. Therefore in the hybrid system the linkage flux of the levitation direction increases. The levitation and restoring force of the rotor is measured. The levitation force of the hybrid system becomes smaller than that of the non-hybrid one by attractive force. The rotor in the hybrid system is supported by the pinning force and attractive force. The restoring force of the hybrid system becomes larger than that of the non-hybrid one because of increasing the linkage flux of the levitation direction.

  12. Discrimination of tooth layers and dental restorative materials using cutting sounds.

    PubMed

    Zakeri, Vahid; Arzanpour, Siamak; Chehroudi, Babak

    2015-03-01

    Dental restoration begins with removing carries and affected tissues with air-turbine rotary cutting handpieces, and later restoring the lost tissues with appropriate restorative materials to retain the functionality. Most restoration materials eventually fail as they age and need to be replaced. One of the difficulties in replacing failing restorations is discerning the boundary of restorative materials, which causes inadvertent removal of healthy tooth layers. Developing an objective and sensor-based method is a promising approach to monitor dental restorative operations and to prevent excessive tooth losses. This paper has analyzed cutting sounds of an air-turbine handpiece to discriminate between tooth layers and two commonly used restorative materials, amalgam and composite. Support vector machines were employed for classification, and the averaged short-time Fourier transform coefficients were selected as the features. The classifier performance was evaluated from different aspects such as the number of features, feature scaling methods, classification schemes, and utilized kernels. The total classification accuracies were 89% and 92% for cases included composite and amalgam materials, respectively. The obtained results indicated the feasibility and effectiveness of the proposed method.

  13. Monoenergetic computed tomography reconstructions reduce beam hardening artifacts from dental restorations.

    PubMed

    Stolzmann, Paul; Winklhofer, Sebastian; Schwendener, Nicole; Alkadhi, Hatem; Thali, Michael J; Ruder, Thomas D

    2013-09-01

    The aim of this study was to assess the potential of monoenergetic computed tomography (CT) images to reduce beam hardening artifacts in comparison to standard CT images of dental restoration on dental post-mortem CT (PMCT). Thirty human decedents (15 male, 58 ± 22 years) with dental restorations were examined using standard single-energy CT (SECT) and dual-energy CT (DECT). DECT data were used to generate monoenergetic CT images, reflecting the X-ray attenuation at energy levels of 64, 69, 88 keV, and at an individually adjusted optimal energy level called OPTkeV. Artifact reduction and image quality of SECT and monoenergetic CT were assessed objectively and subjectively by two blinded readers. Subjectively, beam artifacts decreased visibly in 28/30 cases after monoenergetic CT reconstruction. Inter- and intra-reader agreement was good (k = 0.72, and k = 0.73 respectively). Beam hardening artifacts decreased significantly with increasing monoenergies (repeated-measures ANOVA p < 0.001). Artifact reduction was greatest on monoenergetic CT images at OPTkeV. Mean OPTkeV was 108 ± 17 keV. OPTkeV yielded the lowest difference between CT numbers of streak artifacts and reference tissues (-163 HU). Monoenergetic CT reconstructions significantly reduce beam hardening artifacts from dental restorations and improve image quality of post-mortem dental CT.

  14. Genotoxicity evaluation of dental restoration nanocomposite using comet assay and chromosome aberration test

    NASA Astrophysics Data System (ADS)

    Musa, Marahaini; Thirumulu Ponnuraj, Kannan; Mohamad, Dasmawati; Rahman, Ismail Ab

    2013-01-01

    Nanocomposite is used as a dental filling to restore the affected tooth, especially in dental caries. The dental nanocomposite (KelFil) for tooth restoration used in this study was produced by the School of Dental Sciences, Universiti Sains Malaysia, Malaysia and is incorporated with monodispersed, spherical nanosilica fillers. The aim of the study was to determine the genotoxic effect of KelFil using in vitro genotoxicity tests. The cytotoxicity and genotoxicity of KelFil was evaluated using MTT assay, comet assay and chromosome aberration tests with or without the addition of a metabolic activation system (S9 mix), using the human lung fibroblast cell line (MRC-5). Concurrent negative and positive controls were included. In the comet assay, no comet formation was found in the KelFil groups. There was a significant difference in tail moment between KelFil groups and positive control (p < 0.05). Similarly, no significant aberrations in chromosomes were noticed in KelFil groups. The mitotic indices of treatment groups and negative control were significantly different from positive controls. Hence, it can be concluded that the locally produced dental restoration nanocomposite (KelFil) is non-genotoxic under the present test conditions.

  15. Genotoxicity evaluation of dental restoration nanocomposite using comet assay and chromosome aberration test.

    PubMed

    Musa, Marahaini; Ponnuraj, Kannan Thirumulu; Mohamad, Dasmawati; Rahman, Ismail Ab

    2013-01-11

    Nanocomposite is used as a dental filling to restore the affected tooth, especially in dental caries. The dental nanocomposite (KelFil) for tooth restoration used in this study was produced by the School of Dental Sciences, Universiti Sains Malaysia, Malaysia and is incorporated with monodispersed, spherical nanosilica fillers. The aim of the study was to determine the genotoxic effect of KelFil using in vitro genotoxicity tests. The cytotoxicity and genotoxicity of KelFil was evaluated using MTT assay, comet assay and chromosome aberration tests with or without the addition of a metabolic activation system (S9 mix), using the human lung fibroblast cell line (MRC-5). Concurrent negative and positive controls were included. In the comet assay, no comet formation was found in the KelFil groups. There was a significant difference in tail moment between KelFil groups and positive control (p < 0.05). Similarly, no significant aberrations in chromosomes were noticed in KelFil groups. The mitotic indices of treatment groups and negative control were significantly different from positive controls. Hence, it can be concluded that the locally produced dental restoration nanocomposite (KelFil) is non-genotoxic under the present test conditions.

  16. Inequalities in preventive and restorative dental services in England, Wales and Northern Ireland.

    PubMed

    Cheema, J; Sabbah, W

    2016-09-01

    Aims The objective of this study is to assess socioeconomic inequalities in the use of selected dental procedures.Methods Data is from the Adult Dental Health Survey 2009, a nationally representative cross-sectional survey of England, Northern Ireland and Wales. Overall, 6,279 participants were included in the analysis. Occupational classification and education were used to assess variations in the use of preventive, restorative services and tooth extraction using a series of logistic regression models, adjusting for age, sex, ethnicity, DMFT, self-reported oral health, dental visits and country.Results There were clear socioeconomic variations in the utilisation of preventive and restorative services. In the fully adjusted model those with no educational qualification were less likely to report ever having preventive services than those with a degree (OR 0.48, 95%CI: 0.36,0.65). Similarly, individuals in routine/manual occupation were significantly less likely to report ever having preventive services than those in managerial/professional occupation (OR 0.58, 95%CI: 0.46,0.74) in the fully adjusted model.Conclusion The findings imply that despite relatively equitable access and higher use of dental services in UK, the least educated and those at the bottom of social hierarchy are less likely to have preventive and restorative dental services.

  17. Inequalities in preventive and restorative dental services in England, Wales and Northern Ireland.

    PubMed

    Cheema, J; Sabbah, W

    2016-09-01

    Aims The objective of this study is to assess socioeconomic inequalities in the use of selected dental procedures.Methods Data is from the Adult Dental Health Survey 2009, a nationally representative cross-sectional survey of England, Northern Ireland and Wales. Overall, 6,279 participants were included in the analysis. Occupational classification and education were used to assess variations in the use of preventive, restorative services and tooth extraction using a series of logistic regression models, adjusting for age, sex, ethnicity, DMFT, self-reported oral health, dental visits and country.Results There were clear socioeconomic variations in the utilisation of preventive and restorative services. In the fully adjusted model those with no educational qualification were less likely to report ever having preventive services than those with a degree (OR 0.48, 95%CI: 0.36,0.65). Similarly, individuals in routine/manual occupation were significantly less likely to report ever having preventive services than those in managerial/professional occupation (OR 0.58, 95%CI: 0.46,0.74) in the fully adjusted model.Conclusion The findings imply that despite relatively equitable access and higher use of dental services in UK, the least educated and those at the bottom of social hierarchy are less likely to have preventive and restorative dental services. PMID:27608576

  18. [The atraumatic restorative treatment approach in pediatric dental care: a comparative clinical study].

    PubMed

    Dmitrova, A G; Kulakov, A A

    2015-01-01

    The aim of this study was to assess and compare the discomfort levels during Atraumatic Restorative Treatment and Minimal Cavity Preparation using rotary instruments and Air abrasion method. The results of the study suggest that ART induces less discomfort, therefore this method can be recommended for children who have a fear of dental procedures as well as for children with intellectual disabilities. PMID:26145474

  19. Calculation of the shrinkage-induced residual stress in a viscoelastic dental restorative material

    NASA Astrophysics Data System (ADS)

    Grassia, Luigi; D'Amore, Alberto

    2013-02-01

    A procedure able to describe the curing process of a particulate composite material used in a dental restoration is developed in the ANSYS environment. The material under concern is a multifunctional methacrylate-based composite for dental restoration, activated by visible light. The model accounts for the dependence of the viscoelastic functions on temperature and degree of cure. Three geometries have been considered in the analysis that are representative of three different classes of dental restoration and mainly differ by the C (constrained)-factor, (i.e. the bounded to unbounded surface ratio). It was found that the temperature could give a necrosis in the vicinity of the tooth nerve and that the average stress at the interface between the composite and the tooth scales exponentially with the C-factor. The residual stress at the dental restoration interface is also compared with the uniaxial tensile strength of twelve commercially available composite materials: it clearly appears that the level of residual stress may overcome the strength of the composite, especially at high C-factors.

  20. Quantification of Staphylococcus aureus adhesion forces on various dental restorative materials using atomic force microscopy

    NASA Astrophysics Data System (ADS)

    Merghni, Abderrahmen; Kammoun, Dorra; Hentati, Hajer; Janel, Sébastien; Popoff, Michka; Lafont, Frank; Aouni, Mahjoub; Mastouri, Maha

    2016-08-01

    In the oral cavity dental restorative biomaterials can act as a reservoir for infection with opportunistic Staphylococcus aureus pathogen, which can lead to the occurrence of secondary caries and treatment failures. Our aim was to evaluate the adhesion forces by S. aureus on four dental restorative biomaterials and to correlate this finding to differences in specific surface characteristics. Additionally, the influence of salivary conditioning films in exerted adhesion forces was investigated. The substrate hydrophobicity was measured by goniometer and the surface free energy was calculated using the equilibrium advancing contact angle values of water, formamide, and diiodomethane on the tested surfaces. The surface roughness was determined using atomic force microscope (AFM). Additionally, cell force spectroscopy was achieved to quantify the forces that drive cell-substrate interactions. S. aureus bacterium exerted a considerable adhesion forces on various dental restorative materials, which decreased in the presence of saliva conditioning film. The influence of the surface roughness and free energy in initial adhesion appears to be more important than the effect of hydrophobicity, either in presence or absence of saliva coating. Hence, control of surface properties of dental restorative biomaterials is of crucial importance in preventing the attachment and subsequent the biofilm formation.

  1. Computed tomography evidence of dental restoration as aetiological factor for maxillary sinusitis.

    PubMed

    Connor, S E; Chavda, S V; Pahor, A L

    2000-07-01

    Maxillary sinusitis due to dental causes is usually secondary to periodontal disease or periapical infection and is commonly associated with mucosal thickening of the floor of the maxillary antrum. Computed tomography (CT) is currently the modality of choice for evaluating the extent of disease and any predisposing factors in patients with symptoms of chronic maxillary sinusitis, but it is unable to diagnose dental disease reliably. The presence of restorative dentistry is, however, easily seen at CT and is associated with both periapical and periodontal disease. We aimed to determine whether its presence at CT may predispose to maxillary sinusitis, and in particular to focal mucosal thickening of the sinus floor characteristic of dental origin. Three hundred and thirty maxillary sinus CT images in 165 patients were reviewed for the presence of restorative dentistry in the adjacent teeth, focal maxillary sinus floor mucosal thickening, any maxillary sinus disease (including complete opacification, air fluid levels, diffuse mucosal thickening, focal mucosal thickening) and evidence of a rhinogenic aetiology (osteomeatal complex pathology, mucosal thickening in other sinuses). One hundred and ninety two sinuses adjacent to restorative dentistry and 178 sinuses not adjacent to restorative dentistry were analysed. Focal floor thickening both with, and without, evidence of a rhinogenic aetiology, was significantly more common adjacent to restorative dentistry. Maxillary sinus disease overall was no more common adjacent to restorative dentistry. This work demonstrated that the presence of restorative dentistry predisposes to focal mucosal thickening in the floor of the maxillary sinus and its presence should prompt clinical and radiographical assessment to exclude dental disease as a source of chronic maxillary sinusitis.

  2. Dental age estimation in Malay children based on all permanent teeth types.

    PubMed

    Yusof, M Y P M; Thevissen, P W; Fieuws, S; Willems, G

    2014-03-01

    The applicability of the Willems et al. model was verified on a collected sample of Malay (Malaysian nationality) children. This sample was split in a reference sample to develop a Malay-specific prediction model based on the Willems et al. method and in a test sample to validate this new developed model. Next, the incorporation of third molars into this model was analyzed. Panoramic radiographs (n = 1,403) of Malay children aged between 4 and 14.99 years (n = 702) and subadults aged between 15 and 23.99 years (n = 701) were collected. The left mandibular seven permanent teeth of the children were scored based on the staging technique described by Demirjian and converted to age using the Willems et al. method. Third molar development of all individuals was staged based on the technique described by Gleiser and Hunt modified by Kohler. Differences between dental age and chronological age were calculated and expressed in mean error (ME), mean absolute error (MAE), and root mean square error (RMSE). The Willems et al. model verified on the collected Malay children overestimated chronological age with a ME around 0.45 year. Small differences in ME, MAE, and RMSE between the verified Malay-specific prediction model and the Willems et al. model were observed. An overall neglected decrease in RMSE was detected adding third molar stages to the developed permanent teeth model.

  3. Effects of temperature change and beverage on mechanical and tribological properties of dental restorative composites.

    PubMed

    Ayatollahi, M R; Yahya, Mohd Yazid; Karimzadeh, A; Nikkhooyifar, M; Ayob, Amran

    2015-09-01

    The aim of this study was to investigate the effects of temperature change and immersion in two common beverages on the mechanical and tribological properties for three different types of dental restorative materials. Thermocycling procedure was performed for simulating temperature changes in oral conditions. Black tea and soft drink were considered for beverages. Universal composite, universal nanohybrid composite and universal nanofilled composite, were used as dental materials. The nanoindentation and nanoscratch experiments were utilized to determine the elastic modulus, hardness, plasticity index and wear resistance of the test specimens. The results showed that thermocycling and immersion in each beverage had different effects on the tested dental materials. The mechanical and tribological properties of nanohybrid composite and nanocomposite were less sensitive to temperature change and to immersion in beverages in comparison with those of the conventional dental composite.

  4. Handling characteristics of gallium alloy for dental restoration.

    PubMed

    Mash, L K; Miller, B H; Nakajima, H; Collard, S M; Guo, I Y; Okabe, T

    1993-12-01

    The handling characteristics of a gallium alloy (Gallium Alloy GF) were compared to those of a spherical high-copper amalgam (Tytin). Ten dentists each restored four identical MO preparations in acrylic typodont teeth (no. 30), two with amalgam and two with gallium alloy. Each restoration was evaluated immediately following completion by the operator for six clinically relevant criteria. Each criterion was scored between 1 and 5, where 1 = very poor, 2 = poor, 3 = fair, 4 = good, and 5 = very good. Three two-sided Mann-Whitney tests were used to compare the median scores for significant differences (P < 0.05). The first test indicated no significant difference between scores for the first- and second-placed restorations, within criteria and within alloy type (n = 10). The second test indicated a significant difference between amalgam and gallium alloy, within criteria and within restoration sequence (n = 10), for each criterion except resistance to fracture during removal of the matrix band. The third test indicated a significant difference between amalgam and gallium alloy, within each criteria, combining scores for first- and second-placed restorations (n = 20). During simulated clinical placement, amalgam was rated significantly higher than gallium alloy in each handling characteristic evaluated.

  5. Effects of high temperature on different restorations in forensic identification: Dental samples and mandible

    PubMed Central

    Patidar, Kalpana A; Parwani, Rajkumar; Wanjari, Sangeeta

    2010-01-01

    Introduction: The forensic odontologist strives to utilize the charred human dentition throughout each stage of dental evaluation, and restorations are as unique as fingerprints and their radiographic morphology as well as the types of filling materials are often the main feature for identification. The knowledge of detecting residual restorative material and composition of unrecovered adjacent restoration is a valuable tool-mark in the presumptive identification of the dentition of a burned victim. Gold, silver amalgam, silicate restoration, and so on, have a different resistance to prolonged high temperature, therefore, the identification of burned bodies can be correlated with adequate qualities and quantities of the traces. Most of the dental examination relies heavily on the presence of the restoration as well as the relationship of one dental structure to another. This greatly narrows the research for the final identification that is based on postmortem data. Aim: The purpose of this study is to examine the resistance of teeth and different restorative materials, and the mandible, to variable temperature and duration, for the purpose of identification. Materials and Methods: The study was conducted on 72 extracted teeth which were divided into six goups of 12 teeth each based on the type of restorative material. (Group 1 - unrestored teeth, group 2 - teeth restored with Zn3(PO4)2, group 3 - with silver amalgam, group 4 with glass ionomer cement, group 5 - Ni-Cr-metal crown, group 6 - metal ceramic crown) and two specimens of the mandible. The effect of incineration at 400°C (5 mins, 15 mins, 30 mins) and 1100°C (15 mins) was studied. Results: Damage to the teeth subjected to variable temperatures and time can be categorized as intact (no damage), scorched (superficially parched and discolored), charred (reduced to carbon by incomplete combustion) and incinerated (burned to ashes). PMID:21189989

  6. Utilizing optical coherence tomography for CAD/CAM of indirect dental restorations

    NASA Astrophysics Data System (ADS)

    Chityala, Ravishankar; Vidal, Carola; Jones, Robert

    Optical Coherence Tomography (OCT) has seen broad application in dentistry including early carious lesion detection and imaging defects in resin composite restorations. This study investigates expanding the clinical usefulness by investigating methods to use OCT for obtaining three-dimensional (3D) digital impressions, which can be integrated to CAD/CAM manufacturing of indirect restorations. 3D surface topography `before' and `after' a cavity preparation was acquired by an intraoral cross polarization swept source OCT (CP-OCT) system with a Micro-Electro-Mechanical System (MEMS) scanning mirror. Image registration and segmentation methods were used to digitally construct a replacement restoration that modeled the original surface morphology of a hydroxyapatite sample. After high resolution additive manufacturing (e.g. polymer 3D printing) of the replacement restoration, micro-CT imaging was performed to examine the marginal adaptation. This study establishes the protocol for further investigation of integrating OCT with CAD/CAM of indirect dental restorations.

  7. Cytogenetic genotoxic investigation in peripheral blood lymphocytes of subjects with dental composite restorative filling materials.

    PubMed

    Pettini, F; Savino, M; Corsalini, M; Cantore, S; Ballini, A

    2015-01-01

    Dental composite resins are biomaterials commonly used to aesthetically restore the structure and function of teeth impaired by caries, erosion, or fracture. Residual monomers released from resin restorations as a result of incomplete polymerization processes interact with living oral tissues. The objective of this study was to evaluate the genotoxicity of a common dental composite material (Enamel Plus-HFO), in subjects with average 13 filled teeth with the same material, compared to a control group (subjects having neither amalgam nor composite resin fillings). Genotoxicity assessment of composite materials was carried out in vitro in human peripheral blood leukocytes using sister-chromatid exchange (SCE) and chromosomal aberrations (CA) cytogenetic tests. The results of correlation and multiple regression analyses confirmed the absence of a relationship between SCE/cell, high frequency of SCE(HFC) or CA frequencies and exposure to dental composite materials. These results indicate that composite resins used for dental restorations differ extensively in vivo in their cytotoxic and genotoxic potential and in their ability to affect chromosomal integrity, cell-cycle progression, DNA replication and repair. PMID:25864763

  8. An update on glass fiber dental restorative composites: a systematic review.

    PubMed

    Khan, Abdul Samad; Azam, Maria Tahir; Khan, Maria; Mian, Salman Aziz; Ur Rehman, Ihtesham

    2015-02-01

    Dentistry is a much developed field in the last few decades. New techniques have changed the conventional treatment methods as applications of new dental materials give better outcomes. The current century has suddenly forced on dentistry, a new paradigm regarding expected standards for state-of-the-art patient care. Within the field of restorative dentistry, the incredible advances in dental materials research have led to the current availability of esthetic adhesive restorations. The chemistry and structure of the resins and the nature of the glass fiber reinforced systems in dental composites are reviewed in relation to their influence and properties including mechanical, physical, thermal, biocompatibility, technique sensitivity, mode and rate of failure of restorations on clinical application. It is clear that a deeper understanding of the structure of the polymeric matrix and resin-based dental composite is required. As a result of ongoing research in the area of glass fiber reinforced composites and with the development and advancement of these composites, the future prospects of resin-based composite are encouraging.

  9. Cytogenetic genotoxic investigation in peripheral blood lymphocytes of subjects with dental composite restorative filling materials.

    PubMed

    Pettini, F; Savino, M; Corsalini, M; Cantore, S; Ballini, A

    2015-01-01

    Dental composite resins are biomaterials commonly used to aesthetically restore the structure and function of teeth impaired by caries, erosion, or fracture. Residual monomers released from resin restorations as a result of incomplete polymerization processes interact with living oral tissues. The objective of this study was to evaluate the genotoxicity of a common dental composite material (Enamel Plus-HFO), in subjects with average 13 filled teeth with the same material, compared to a control group (subjects having neither amalgam nor composite resin fillings). Genotoxicity assessment of composite materials was carried out in vitro in human peripheral blood leukocytes using sister-chromatid exchange (SCE) and chromosomal aberrations (CA) cytogenetic tests. The results of correlation and multiple regression analyses confirmed the absence of a relationship between SCE/cell, high frequency of SCE(HFC) or CA frequencies and exposure to dental composite materials. These results indicate that composite resins used for dental restorations differ extensively in vivo in their cytotoxic and genotoxic potential and in their ability to affect chromosomal integrity, cell-cycle progression, DNA replication and repair.

  10. Determination of light elements in amalgam restorations. [Dental amalgam

    SciTech Connect

    Hanson, A.L.; Jones, K.W.; Kraner, H.W.; Osborne, J.W.; Nelson, G.V.

    1982-01-01

    Rutherford backscattering has been used to measure the major elemental compositions in the near-surface regions of freshly prepared and used samples of dental amalgam. A depletion from bulk stoichiometry of the major elements, which indicates an accumulation of lighter elements on the surface of the materials, has been observed. Increases in the F, Na, Cl, P, O, C, and N concentrations between freshly prepared samples and used samples were measured by observation of gamma rays produced by proton and deuteron induced reactions.

  11. Imagistic evaluation of direct dental restoration: en face OCT versus SEM and microCT

    NASA Astrophysics Data System (ADS)

    Negruţiu, Meda L.; Sinescu, Cosmin; Topala, Florin; Ionita, Ciprian; Marcauteanu, Corina; Petrescu, Emanuela L.; Podoleanu, Adrian G.

    2011-06-01

    There are several methods known which are used to assess the quality of direct dental restorations, but most of them are invasive. These lead to the destruction of the probes and often no conclusion could be drawn in respect to the existence of any microleakage in the investigated areas of interest. Optical tomographic techniques are of particular importance in the medical imaging field, because these techniques can provide non-invasive diagnostic images. Using an en-face version of OCT, we have recently demonstrated real time thorough evaluation of quality of dental fillings. The purpose of this in vitro study was to validate the en face OCT imagistic evaluation of direct dental restoration by using scanning electron microscopy (SEM) and microcomputer tomography (μCT). Teeth after several treatment methods are imaged in order to detect material defects and to asses the marginal adaptation at the dental hard tissue walls. SEM investigations evidenced the nonlinear aspect of the interface between the filling material and the buccal and lingual walls in some samples. The results obtained by μCT revealed also some material defects inside the fillings and at the interfaces with the rootcanal walls. The advantages of the OCT method consist in non-invasiveness and high resolution. En face OCT investigations permit to visualize a more complex stratificated structure at the interface filling material/dental hard tissue and in the apical region.

  12. Determination of optical properties in dental restorative biomaterials using the inverse-adding-doubling method

    NASA Astrophysics Data System (ADS)

    Fernández-Oliveras, Alicia; Rubiño, Manuel; Pérez, María. M.

    2013-11-01

    Light propagation in biological media is characterized by the absorption coefficient, the scattering coefficient, the scattering phase function, the refractive index, and the surface conditions (roughness). By means of the inverse-adding-doubling (IAD) method, transmittance and reflectance measurements lead to the determination of the absorption coefficient and the reduced scattering coefficient. The additional measurement of the phase function performed by goniometry allows the separation of the reduced scattering coefficient into the scattering coefficient and the scattering anisotropy factor. The majority of techniques, such as the one utilized in this work, involve the use of integrating spheres to measure total transmission and reflection. We have employed an integrating sphere setup to measure the total transmittance and reflectance of dental biomaterials used in restorative dentistry. Dental biomaterials are meant to replace dental tissues, such as enamel and dentine, in irreversibly diseased teeth. In previous works we performed goniometric measurements in order to evaluate the scattering anisotropy factor for these kinds of materials. In the present work we have used the IAD method to combine the measurements performed using the integrating sphere setup with the results of the previous goniometric measurements. The aim was to optically characterize the dental biomaterials analyzed, since whole studies to assess the appropriate material properties are required in medical applications. In this context, complete optical characterizations play an important role in achieving the fulfillment of optimal quality and the final success of dental biomaterials used in restorative dentistry.

  13. The failure of amalgam dental restorations due to cyclic fatigue crack growth.

    PubMed

    Arola, D; Huang, M P; Sultan, M B

    1999-06-01

    In this study a restored mandibular molar with different Class II amalgam preparations was examined to analyze the potential for restoration failure attributed to cyclic fatigue crack growth. A finite element analysis was used to determine the stress distribution along the cavo-surface margin which results from occlusal loading of each restoration. The cyclic crack growth rate of sub-surface flaws located along the dentinal cavo-surface margin were determined utilizing the Paris law. Based on similarities in material properties and lack of fatigue property data for dental biomaterials, the cyclic fatigue crack growth parameters for engineering ceramics were used to approximate the crack growth behavior. It was found that flaws located within the dentine along the buccal and lingual margins can significantly reduce the fatigue life of restored teeth. Sub-surface cracks as short as 25 microm were found capable of promoting tooth fracture well within 25 years from the time of restoration. Furthermore, cracks longer than 100 microm reduced the fatigue life to less than 5 years. Consequently, sub-surface cracks introduced during cavity preparation with conventional dental burrs may serve as a principal source for premature restoration failure.

  14. DENTAL PRACTITIONERS' ATTITUDES, SUBJECTIVE NORMS AND INTENTIONS TO PRACTICE ATRAUMATIC RESTORATIVE TREATMENT (ART) IN TANZANIA

    PubMed Central

    Kikwilu, Emil N.; Frencken, Jo E.; Mulder, Jan; Masalu, Joyce R.

    2009-01-01

    The aim of this study was to describe the attitude and subjective norm of dental practitioners towards practicing the atraumatic restorative treatment (ART) in Tanzania. A pre-tested questionnaire on attitudes and subjective norms to practice ART was mailed to all 147 dental practitioners working in the regional and district government clinics. The independent variables were: gender, working experience, qualification and ever heard of ART. The dependent variables were: attitude, subjective norm and intention to practice ART. Chi-square tests and multiple regression analysis were used to test for effects between independent and dependent variables. Significance level was set at 5%. A total of 138 practitioners returned completed questionnaires. More experienced dental practitioners encountered moderate social pressure than less experienced dental practitioners, who met strong social pressure (p=0.045). A total of 73.2% of dental practitioners felt that ART was worth introducing in Tanzania, 92.8% recommended ART training for all dental practitioners and 97.8% recommended inclusion of ART in dental curricula. Positive attitude, strong subjective norm and high intention to practice ART were recorded in 76.3%, 28.1% and 90.6% of the practitioners, respectively. Only subjective norm had a statistically significant influence on the intention to practice ART (p<0.0001). The results indicated that dental practitioners were willing to have ART introduced in Tanzania and had positive attitudes towards practicing this technique. Nevertheless, their intention to perform ART was strongly influenced by social pressures. Therefore, in order to have a successful introduction of ART in Tanzania, people who matter in the daily practice of dental practitioners need to accept and appraise the ART approach positively. PMID:19274393

  15. Testing adhesion of direct restoratives to dental hard tissue - a review.

    PubMed

    Salz, Ulrich; Bock, Thorsten

    2010-10-01

    This articles concerns itself with the testing of adhesion between direct restoratives and dental hard tissue, ie, enamel and dentin. The aim is to survey available methods for adhesion testing and influential parameters affecting experimental outcome. The testing of adhesion to indirect restorative materials, eg, ceramics and metals, is beyond the scope of this article and shall be discussed elsewhere. The longevity and success of modern dental restorations very often relies on potent dental adhesives to provide durable bonds between the dental hard substance and the restorative composite. To predict the clinical outcome of such restorative treatment, a large variety of in vitro laboratory tests and clinical in vivo experiments have been devised, analyzed, and published. The purpose of this review is to provide a current overview of bond strength testing methods and their applicability to the characterization of dental adhesives. Regardless of the method employed, subtle variations in sample preparation may already severely impact test results, usually necessitating at least co-testing of a well-known internal reference to allow conclusive interpretation. This article attempts to list and discuss the most influential parameters, such as substrate nature, age, health status, storage, clinically relevant pre-treatment, and sample preparation. Special attention is devoted to the last aspect, as numerous publications have stressed the tremendous influence of preparatory parameters on the validity and scope of obtained data. Added to the large variety of such factors, an equally large diversity of load-applying procedures exists to actually quantify adhesion between composites and dental hard substance. This article summarizes the basics of macro and micro approaches to shear and tensile bond strength testing, as well as push- and pull-out tests. The strengths and weaknesses inherent to each method and influential test parameters are reviewed and methods for

  16. Modelling the longevity of dental restorations by means of a CBR system.

    PubMed

    Aliaga, Ignacio J; Vera, Vicente; De Paz, Juan F; García, Alvaro E; Mohamad, Mohd Saberi

    2015-01-01

    The lifespan of dental restorations is limited. Longevity depends on the material used and the different characteristics of the dental piece. However, it is not always the case that the best and longest lasting material is used since patients may prefer different treatments according to how noticeable the material is. Over the last 100 years, the most commonly used material has been silver amalgam, which, while very durable, is somewhat aesthetically displeasing. Our study is based on the collection of data from the charts, notes, and radiographic information of restorative treatments performed by Dr. Vera in 1993, the analysis of the information by computer artificial intelligence to determine the most appropriate restoration, and the monitoring of the evolution of the dental restoration. The data will be treated confidentially according to the Organic Law 15/1999 on 13 December on the Protection of Personal Data. This paper also presents a clustering technique capable of identifying the most significant cases with which to instantiate the case-base. In order to classify the cases, a mixture of experts is used which incorporates a Bayesian network and a multilayer perceptron; the combination of both classifiers is performed with a neural network.

  17. Modelling the Longevity of Dental Restorations by means of a CBR System

    PubMed Central

    Aliaga, Ignacio J.; Vera, Vicente; García, Alvaro E.

    2015-01-01

    The lifespan of dental restorations is limited. Longevity depends on the material used and the different characteristics of the dental piece. However, it is not always the case that the best and longest lasting material is used since patients may prefer different treatments according to how noticeable the material is. Over the last 100 years, the most commonly used material has been silver amalgam, which, while very durable, is somewhat aesthetically displeasing. Our study is based on the collection of data from the charts, notes, and radiographic information of restorative treatments performed by Dr. Vera in 1993, the analysis of the information by computer artificial intelligence to determine the most appropriate restoration, and the monitoring of the evolution of the dental restoration. The data will be treated confidentially according to the Organic Law 15/1999 on 13 December on the Protection of Personal Data. This paper also presents a clustering technique capable of identifying the most significant cases with which to instantiate the case-base. In order to classify the cases, a mixture of experts is used which incorporates a Bayesian network and a multilayer perceptron; the combination of both classifiers is performed with a neural network. PMID:25866792

  18. [DENTAL STATUS OF PATIENTS WITH INTRAUTERINE GROWTH RESTRICTION IN PAST HISTORY DURING PERIOD OF REMOVABLE AND PERMANENT DENTITION].

    PubMed

    Garmash, O V; Ryabokon, E N

    2014-12-01

    The analysis of the dental status in patients with IUGR in past history in period of removable and permanent dentition was conducted. 39 patients with intrauterine growth retardation in past history were examined. The clinical, statistical methods were held. Concluded that the child, who was born with IUGR, later in future life, has a great risk of dental diseases. The most considerable violations were found in patients with "symmetrical" form of intrauterine growth retardation. It is proposed to use clinical markers as possible predictors of periodontal diseases.

  19. The use of amalgam powder and calcium hydroxide to recreate a radiopaque image of a lost dental restoration.

    PubMed

    Shiroma, Calvin Y

    2002-05-01

    Radiographs of dental restorations are highly reliable when used to identify postmortem dental remains. A problem exists if key dental restorations are missing or defective, which results in the loss of a comparative radiographic image. This article describes a simple method allowing the odontologist to quickly recreate a temporary radiopaque restoration. This article presents a method of using amalgam powder (radiopaque material) and calcium hydroxide (radiopaque material and transport medium for the amalgam powder) to recreate a radiopaque image on a tooth that has lost a dental restoration. Amalgam powder and calcium hydroxide is easily obtained (in any dental office), fairly clean, easy to manipulate, inexpensive, inert, stable, and able to be removed without damaging the dental remains. The amalgam powder/calcium hydroxide mixture can easily be re-shaped or modified to reflect the radiopaque image of the original restoration. Radiographic comparison of the "restored" dental remains to the antemortem radiographs is now possible. The use of this technique is presented in a case report. PMID:12051346

  20. The use of amalgam powder and calcium hydroxide to recreate a radiopaque image of a lost dental restoration.

    PubMed

    Shiroma, Calvin Y

    2002-05-01

    Radiographs of dental restorations are highly reliable when used to identify postmortem dental remains. A problem exists if key dental restorations are missing or defective, which results in the loss of a comparative radiographic image. This article describes a simple method allowing the odontologist to quickly recreate a temporary radiopaque restoration. This article presents a method of using amalgam powder (radiopaque material) and calcium hydroxide (radiopaque material and transport medium for the amalgam powder) to recreate a radiopaque image on a tooth that has lost a dental restoration. Amalgam powder and calcium hydroxide is easily obtained (in any dental office), fairly clean, easy to manipulate, inexpensive, inert, stable, and able to be removed without damaging the dental remains. The amalgam powder/calcium hydroxide mixture can easily be re-shaped or modified to reflect the radiopaque image of the original restoration. Radiographic comparison of the "restored" dental remains to the antemortem radiographs is now possible. The use of this technique is presented in a case report.

  1. New layer-based imaging and rapid prototyping techniques for computer-aided design and manufacture of custom dental restoration.

    PubMed

    Lee, M-Y; Chang, C-C; Ku, Y C

    2008-01-01

    Fixed dental restoration by conventional methods greatly relies on the skill and experience of the dental technician. The quality and accuracy of the final product depends mostly on the technician's subjective judgment. In addition, the traditional manual operation involves many complex procedures, and is a time-consuming and labour-intensive job. Most importantly, no quantitative design and manufacturing information is preserved for future retrieval. In this paper, a new device for scanning the dental profile and reconstructing 3D digital information of a dental model based on a layer-based imaging technique, called abrasive computer tomography (ACT) was designed in-house and proposed for the design of custom dental restoration. The fixed partial dental restoration was then produced by rapid prototyping (RP) and computer numerical control (CNC) machining methods based on the ACT scanned digital information. A force feedback sculptor (FreeForm system, Sensible Technologies, Inc., Cambridge MA, USA), which comprises 3D Touch technology, was applied to modify the morphology and design of the fixed dental restoration. In addition, a comparison of conventional manual operation and digital manufacture using both RP and CNC machining technologies for fixed dental restoration production is presented. Finally, a digital custom fixed restoration manufacturing protocol integrating proposed layer-based dental profile scanning, computer-aided design, 3D force feedback feature modification and advanced fixed restoration manufacturing techniques is illustrated. The proposed method provides solid evidence that computer-aided design and manufacturing technologies may become a new avenue for custom-made fixed restoration design, analysis, and production in the 21st century.

  2. New layer-based imaging and rapid prototyping techniques for computer-aided design and manufacture of custom dental restoration.

    PubMed

    Lee, M-Y; Chang, C-C; Ku, Y C

    2008-01-01

    Fixed dental restoration by conventional methods greatly relies on the skill and experience of the dental technician. The quality and accuracy of the final product depends mostly on the technician's subjective judgment. In addition, the traditional manual operation involves many complex procedures, and is a time-consuming and labour-intensive job. Most importantly, no quantitative design and manufacturing information is preserved for future retrieval. In this paper, a new device for scanning the dental profile and reconstructing 3D digital information of a dental model based on a layer-based imaging technique, called abrasive computer tomography (ACT) was designed in-house and proposed for the design of custom dental restoration. The fixed partial dental restoration was then produced by rapid prototyping (RP) and computer numerical control (CNC) machining methods based on the ACT scanned digital information. A force feedback sculptor (FreeForm system, Sensible Technologies, Inc., Cambridge MA, USA), which comprises 3D Touch technology, was applied to modify the morphology and design of the fixed dental restoration. In addition, a comparison of conventional manual operation and digital manufacture using both RP and CNC machining technologies for fixed dental restoration production is presented. Finally, a digital custom fixed restoration manufacturing protocol integrating proposed layer-based dental profile scanning, computer-aided design, 3D force feedback feature modification and advanced fixed restoration manufacturing techniques is illustrated. The proposed method provides solid evidence that computer-aided design and manufacturing technologies may become a new avenue for custom-made fixed restoration design, analysis, and production in the 21st century. PMID:18183523

  3. How Dentists Diagnose and Treat Defective Restorations: Evidence from The Dental PBRN

    PubMed Central

    Gordan, Valeria V; Garvan, Cynthia W; Richman, Joshua S; Fellows, Jeffrey L; Rindal, D. Brad; Qvist, Vibeke; Heft, Marc W.; Williams, O Dale; Gilbert, Gregg H

    2010-01-01

    Objectives to (1) identify and quantify the types of treatment that dentists in general dental practice use to manage defective dental restorations; and (2) identify characteristics that are associated with these dentists’ decisions to replace existing restorations. The Dental Practice-Based Research Network (DPBRN) comprises dentists in outpatient practices from five regions: AL/MS: Alabama/Mississippi, FL/GA: Florida/Georgia, MN: dentists employed by HealthPartners and private practitioners in Minnesota, PDA: Permanente Dental Associates in cooperation with Kaiser Permanente’s Center for Health Research, and SK: Denmark, Norway, and Sweden. Methods A questionnaire was sent to all DPBRN practitioner-investigators who reported doing at least some restorative dentistry (n=901). Questions included clinical case scenarios that used text and clinical photographs of defective restorations. Dentists were asked what type of treatment, if any, they would do in each scenario. Treatment options ranged from no treatment to full replacement of the restoration, with or without different preventive treatment options. We used logistic regression to analyze associations between the decision to intervene surgically (repair or replace) and specific dentist, practice, and patient characteristics. Results 512 (57%) DPBRN practitioner-investigators completed the survey. A total of 65% of dentists would replace a composite restoration when the defective margin is located on dentin; 49% would repair it when the defective margin is located on enamel. Most (52%) would not intervene surgically when the restoration in the scenario was amalgam. Dentists participating in solo or small private practice (SPP) chose surgical intervention more often than dentists who participate in large group practices (LGP) or in public health practices (PHP) (p<.0001). Dentists who do not routinely assess caries risk during treatment planning were more likely to intervene surgically and less likely to

  4. Bacteria of Dental Caries in Primary and Permanent Teeth in Children and Young Adults▿

    PubMed Central

    Aas, Jørn A.; Griffen, Ann L.; Dardis, Sara R.; Lee, Alice M.; Olsen, Ingar; Dewhirst, Floyd E.; Leys, Eugene J.; Paster, Bruce J.

    2008-01-01

    Although Streptococcus mutans has been implicated as a major etiological agent of dental caries, our cross-sectional preliminary study indicated that 10% of subjects with rampant caries in permanent teeth do not have detectable levels of S. mutans. Our aims were to use molecular methods to detect all bacterial species associated with caries in primary and permanent teeth and to determine the bacterial profiles associated with different disease states. Plaque was collected from 39 healthy controls and from intact enamel and white-spot lesions, dentin lesions, and deep-dentin lesions in each of 51 subjects with severe caries. 16S rRNA genes were PCR amplified, cloned, and sequenced to determine species identities. In a reverse-capture checkerboard assay, 243 samples were analyzed for 110 prevalent bacterial species. A sequencing analysis of 1,285 16S rRNA clones detected 197 bacterial species/phylotypes, of which 50% were not cultivable. Twenty-two new phylotypes were identified. PROC MIXED tests revealed health- and disease-associated species. In subjects with S. mutans, additional species, e.g., species of the genera Atopobium, Propionibacterium, and Lactobacillus, were present at significantly higher levels than those of S. mutans. Lactobacillus spp., Bifidobacterium dentium, and low-pH non-S. mutans streptococci were predominant in subjects with no detectable S. mutans. Actinomyces spp. and non-S. mutans streptococci were predominant in white-spot lesions, while known acid producers were found at their highest levels later in disease. Bacterial profiles change with disease states and differ between primary and secondary dentitions. Bacterial species other than S. mutans, e.g., species of the genera Veillonella, Lactobacillus, Bifidobacterium, and Propionibacterium, low-pH non-S. mutans streptococci, Actinomyces spp., and Atopobium spp., likely play important roles in caries progression. PMID:18216213

  5. An evaluation of microleakage of various glass ionomer based restorative materials in deciduous and permanent teeth: An in vitro study

    PubMed Central

    Singla, Teena; Pandit, I.K.; Srivastava, Nikhil; Gugnani, Neeraj; Gupta, Monika

    2011-01-01

    Aim To evaluate the microleakage of recently available glass ionomer based restorative materials (GC Fuji IX GP, GC Fuji VII, and Dyract) and compare their microleakage with the previously existing glass ionomer restorative materials (GC Fuji II LC) in primary and permanent teeth. Method One hundred and fifty (75 + 75) non-carious deciduous and permanent teeth were restored with glass ionomer based restorative materials after making class I cavities. Samples were subjected to thermocycling after storing in distilled water for 24 h. Two coats of nail polish were applied 1 mm short of restorative margins and samples sectioned buccolingually after storing in methylene blue dye for 24 h. Microleakage was assessed using stereomicroscope. Result Significant differences (P < 0.05) were found when inter group comparisons were done. Except when GC Fuji VII (Group III) was compared with GC Fuji II LC (Group II) and Dyract (Group IV), non-significant differences (P > 0.05) were observed. It was found that there was no statistically significant difference when the means of microleakage of primary teeth were compared with those of permanent teeth. Conclusions GC Fuji IX GP showed maximum microleakage and GC Fuji VII showed least microleakage. PMID:23960526

  6. Perfluorotriethylene glycol dimethacrylate modified composite resins for improved dental restoratives

    NASA Astrophysics Data System (ADS)

    Wang, Guigui

    The studies described in this dissertation focus on improvement of water resistance and durability of current dental composite resins. The physical, thermal and mechanical properties of the diluent fluorinated monomer, perfluorotriethylene glycol methacrylate (FTEGDMA), FTEGDMA-containing neat resin and its formulated composite resins were evaluated and compared with the conventional visible light-cured (VLC) dental composite resins. Further, the biocompatibility of this monomer and its cured resins were investigated and compared with their conventional counterparts. The results showed that the FTEGDMA-containing neat resin and its composite systems showed more water resistance and longer durability, compared to the conventional Bisphenol A glycol dimethacrylate/triethylene glycol dimethacrylate (BisGMA/TEGDMA) system. The preliminary in vitro biocompatibility test showed that FTEGDMA favored cell growth, compared to the conventional dental resins. The first study investigated basic physical properties of the diluent FTEGDMA monomer. The results showed that the FTEGDMA exhibited lower viscosity, lower refractive index, and a smaller contact angle, which were all beneficial to lowering the water sorption and increasing hydrophobicity. The second study evaluated some physical, thermal, and mechanical properties of the FTEGDMA based neat resins, including polymerization shrinkage, contact angle, water sorption, glass-transitions, dynamic modulus, thermal expansion, compressive strength, and diametral tensile strength. The results showed that the FTEGDMA diluent exhibited significant less water sorption and lower polymerization shrinkage and the BisEMA also contributed towards reducing water sorption. The third study investigated the effects of the FTEGDMA on the mechanical properties of the composite resins including flexural strength (FS), diametral tensile strength (DTS) and wear resistance (WR). In addition, the fracture surface topography of the tested materials

  7. Bilateral dens evaginatus (talon cusp) in permanent maxillary lateral incisors: a rare developmental dental anomaly with great clinical significance

    PubMed Central

    Manuja, Naveen; Chaudhary, Seema; Nagpal, Rajni; Rallan, Mandeep

    2013-01-01

    Talon cusp is an accessory cusp-like structure which projects from the cingulum area or cementoenamel junction. It is important for dentists to be aware of the potential complications that may occur with talon cusp. Early diagnosis and treatment is important, especially to prevent pulpal complications in permanent teeth which may be in developing stage in paediatric patients. The purpose of this paper is to report a case of bilateral talon cusp in permanent maxillary lateral incisors. Associated dental anomalies and clinical problems are discussed along with successful management of the case with conservative therapy. PMID:23813995

  8. Understanding dental CAD/CAM for restorations--dental milling machines from a mechanical engineering viewpoint. Part B: labside milling machines.

    PubMed

    Lebon, Nicolas; Tapie, Laurent; Duret, Francois; Attal, Jean-Pierre

    2016-01-01

    Nowadays, dental numerical controlled (NC) milling machines are available for dental laboratories (labside solution) and dental production centers. This article provides a mechanical engineering approach to NC milling machines to help dental technicians understand the involvement of technology in digital dentistry practice. The technical and economic criteria are described for four labside and two production center dental NC milling machines available on the market. The technical criteria are focused on the capacities of the embedded technologies of milling machines to mill prosthetic materials and various restoration shapes. The economic criteria are focused on investment cost and interoperability with third-party software. The clinical relevance of the technology is discussed through the accuracy and integrity of the restoration. It can be asserted that dental production center milling machines offer a wider range of materials and types of restoration shapes than labside solutions, while labside solutions offer a wider range than chairside solutions. The accuracy and integrity of restorations may be improved as a function of the embedded technologies provided. However, the more complex the technical solutions available, the more skilled the user must be. Investment cost and interoperability with third-party software increase according to the quality of the embedded technologies implemented. Each private dental practice may decide which fabrication option to use depending on the scope of the practice.

  9. Refractory chronic spontaneous urticaria and permanent atrial fibrillation associated with dental infection: Mere coincidence or something more to it?

    PubMed

    Kasperska-Zajac, Alicja; Grzanka, Alicja; Kowalczyk, Jacek; Wyszyńska-Chłap, Magdalena; Lisowska, Grażyna; Kasperski, Jacek; Jarząb, Jerzy; Misiołek, Maciej; Kalarus, Zbigniew

    2016-03-01

    Controversy surrounds the role of dental infection/inflammation in the oral cavity in chronic spontaneous urticaria (CSU) and atrial fibrillation (AF), which is mainly due to scarce literature in this area. Therefore, this case report and review of literature illustrate a possible association between the acute-phase response (APR) and clinical conditions, such as CSU and dental infection/inflammation of oral cavity and AF.We describe a 36-year-old man with an 8-year history of difficult-to-treat, uncontrolled CSU, co-existent with dental infection/inflammatory processes of oral cavity and permanent atrial fibrillation (AF). In the presented case, the most likely triggering or aggravating/maintaining factor of the symptoms was the inflammation/dental infection of the oral cavity because of rapid reduction of the urticarial symptoms, drug doses, and serum CRP levels after the dental therapy. Dental treatment may have a beneficial effect on the systemic inflammatory response, reducing/normalizing the circulating levels of APR markers. APR activation appears to worsen CSU course, early identification and treatment of infectious/inflammatory foci in the oral cavity would form the mainstay of supportive therapy for CU probably through reduction of the systemic inflammatory burden. APR associated with infectious/inflammatory foci in the oral cavity could be taken into account as a predisposing agents to AF.

  10. Priorities for future innovation, research, and advocacy in dental restorative materials.

    PubMed

    Watson, T; Fox, C H; Rekow, E D

    2013-11-01

    Innovations in materials science, both within and outside of dentistry, open opportunities for the development of exciting direct restorative materials. From rich dialog among experts from dental and non-dental academic institutions and industry, as well as those from policy, research funding, and professional organizations, we learned that capitalizing on these opportunities is multifactorial and far from straightforward. Beginning from the point when a restoration is needed, what materials, delivery systems, and skills are needed to best serve the most people throughout the world's widely varied economic and infrastructure systems? New research is a critical element in progress. Effective advocacy can influence funding and drives change in practice and policy. Here we articulate both research and advocacy priorities, with the intention of focusing the energy and expertise of our best scientists on making a difference, bringing new innovations to improve oral health. PMID:24129817

  11. Factors affecting the placement or replacement of direct restorations in a dental school

    PubMed Central

    Silvani, Samara; Trivelato, Roberta Ferreira; Nogueira, Ruchele Dias; Gonçalves, Luciano de Souza; Geraldo-Martins, Vinícius Rangel

    2014-01-01

    Context: The knowledge of the reasons for the placement of direct restorations makes possible to trace an epidemiological profile of a specific population and to direct the teaching of dentistry to techniques that are commonly used today and will be continued performed in the future. Purpose: The aim of this study was to verify the reasons for placement and replacement of direct restorations in patients treated in the Dental Clinic of the Uberaba University – Brazil. Materials and Methods: This study evaluated 306 restorative procedures carried out on 60 patients. During the treatment planning, a form that contained information about the patient's gender, tooth number, the classification of restorations, the reasons for placement and replacement of amalgam and tooth-colored restorations, the material that had to be removed and the new material used to fill the cavities was filled for each patient. Statistical analysis was carried out using Chi-square test (α = 0.05). Results: The data showed that most of the patients were female (66.7%). Of all the restorations placed, 60.45% were 1st-time placements, while 39.55% were replacements. For 1st-time restorations, the main reason for placement was primary caries (76.76%), followed by non-carious cervical lesions (15.14%). The amalgam restorations were replaced more frequently (67.77%). The primary reason for replacements was the presence of secondary caries (for both previous amalgam (42.68%) and composite (66.67%) restorations (P < 0.05). The resin composite was the most indicated material for the new restorations (98.04%) (P < 0.05). Conclusions: The main reason for placement of direct restorations was primary caries, while secondary caries was the main reason for replacements. In almost all cases, the material used to fill the cavities was the resin composite. PMID:24808696

  12. Evidence summary: which dental liners under amalgam restorations are more effective in reducing postoperative sensitivity?

    PubMed

    Nasser, Mona

    2011-06-10

    Since August 2009, members of the Primary Care Dentistry Research Forum (www.dentistryresearch.org) have taken part in an online vote to identify questions in day-to-day practice that they felt most needed to be answered with conclusive research. The question that receives the most votes each month forms the subject of a critical appraisal of the relevant literature. Each month a new round of voting takes place to decide which further questions will be reviewed. Dental practitioners and dental care professionals are encouraged to take part in the voting and submit their own questions to be included in the vote by joining the website. The paper below details a summary of the findings of the ninth critical appraisal. In order to address the question raised by dentistry research forum, first a search was conducted for systematic reviews on the topic. There was one systematic review retrieved comparing bonded amalgam restorations versus non-bonded amalgam restorations. However, there was no other systematic review identified assessing the effectiveness of dental liners under amalgam restorations in general. Therefore, a search was conducted for any randomised controlled trial (RCT) comparing use of a lining under amalgam restorations versus no lining or RCTs comparing differing lining materials under amalgam against each other. There were eight relevant RCTs identified. Due to the low quality, small sample sizes or lack of adequate reporting of the outcome data, the evidence is inadequate to claim or refute a difference in postoperative sensitivity between different dental liners. Further well-conducted RCTs are needed to answer this question. These RCTs would be preferably included and synthesised in a systematic review.

  13. [Water absorption of five dental resins used in bonded restorations].

    PubMed

    Gillet, D; Dupuis, V

    2002-12-01

    The actual restorative dentistry need to bond material which are under the constraint of saliva likely, as all liquid, to enter inside the product with time and to modify its characteristics. In this study, we compare the behaviour of five materials opposite water absorption, in vitro, until one year: two composite resins (Tetric et Pertac II), two ceromer (ceromer (Tetric ceram et Tetric flow) and one compomer (Hytac(r)). Each pastille weight is expressed in percentage of initial weight. All materials loose weight in the first hours except Tetric ceram which stay stable. At 48 h, all materials except Pertac II get back their initial weight. At long-term, all the materials are stable with a profit of 1% for Hytac, 0.5% for Tetric, Tetric ceram et Tetric flow and a loss of à 0.3% for Pertac II. As a result of this study, we understand why the clinical used of Hytac must be done following strict conditions.

  14. Seventeen Years of Using Flowable Resin Restoratives--A Dental Practitioner's Personal Clinical Review.

    PubMed

    Firla, Markus Th

    2015-04-01

    Seen through the author's eyes on the basis of his practising dentistry for almost three decades, light-activated flowable resin restoratives (FRCs) or, in common clinical dental terminology, flowable composites have gradually gained major importance in restorative dentistry. Inputs to this ongoing trend are coming from continuous improvements in material properties and the favourable handling characteristics experienced with this particular group of restoratives. Intended to be used in direct adhesive filling procedures, the number and variety of recent generations of flowable composites for lining, restoration of all cavity classes (I-V), core build-ups and, more recently, 'bulk-fill-restorations', however, necessitates a profound clinical understanding of the selective use of flowable composites to ensure clinical success and guarantee long-term high quality results. Clinical relevance: Today's flowable composites allow for reliable restoration of all kinds of defects. However, both the handling characteristics and the material properties of FRCs must be fully understood before taking advantage of their potentially excellent clinical performance. PMID:26076545

  15. Dental implants with the periodontium: a new approach for the restoration of missing teeth.

    PubMed

    Lin, Cheng; Dong, Qing-Shan; Wang, Lei; Zhang, Jun-Rui; Wu, Li-An; Liu, Bao-Lin

    2009-01-01

    Tooth loss is a common occurrence in mankind and damages human health. Osseointegrated dental implants have been successfully used as a popular prosthetic restoration for the missing teeth for many years. However, osseointegration, representing a direct connection between the implant and bone tissue without the periodontium, causes some inevitable problems, such as masticatory force concentration and immobility of the dental implant. Thus, an ideal dental implant should have its own peri-implant periodontium, as do the natural teeth. A number of attempts have been made to reconstruct the periodontium around the implants. Unfortunately, it has been established that a predictable periodontal reconstruction, especially the acellular cementum reconstruction on the surface of the implant, is a very difficult task. In this paper, we propose the hypothesis that the cementum may be a special phenotype of the bone tissue, on the basis of its strong similarity in development, structure, and function. In a certain condition, the bone tissue may change to cementum for special functional needs. In accordance with this hypothesis, we consider a novel approach to reconstruct the peri-implant tissues. Unlike previous studies, this approach imitates the tooth re-plantation process. The key point is to convert the implant-surrounding bone tissues to cementum as a result of adaptive changes to the implant-support demands. This hypothesis, if proven to be valid, will not only represent a breakthrough in cementum research, but also will open a new door to the restoration of missing teeth. PMID:18829177

  16. Swept source optical coherence tomography for quantitative and qualitative assessment of dental composite restorations

    NASA Astrophysics Data System (ADS)

    Sadr, Alireza; Shimada, Yasushi; Mayoral, Juan Ricardo; Hariri, Ilnaz; Bakhsh, Turki A.; Sumi, Yasunori; Tagami, Junji

    2011-03-01

    The aim of this work was to explore the utility of swept-source optical coherence tomography (SS-OCT) for quantitative evaluation of dental composite restorations. The system (Santec, Japan) with a center wavelength of around 1300 nm and axial resolution of 12 μm was used to record data during and after placement of light-cured composites. The Fresnel phenomenon at the interfacial defects resulted in brighter areas indicating gaps as small as a few micrometers. The gap extension at the interface was quantified and compared to the observation by confocal laser scanning microscope after trimming the specimen to the same cross-section. Also, video imaging of the composite during polymerization could provide information about real-time kinetics of contraction stress and resulting gaps, distinguishing them from those gaps resulting from poor adaptation of composite to the cavity prior to polymerization. Some samples were also subjected to a high resolution microfocus X-ray computed tomography (μCT) assessment; it was found that differentiation of smaller gaps from the radiolucent bonding layer was difficult with 3D μCT. Finally, a clinical imaging example using a newly developed dental SS-OCT system with an intra-oral scanning probe (Panasonic Healthcare, Japan) is presented. SS-OCT is a unique tool for clinical assessment and laboratory research on resin-based dental restorations. Supported by GCOE at TMDU and NCGG.

  17. Children's stress during a restorative dental treatment: assessment using salivary cortisol measurements.

    PubMed

    Akyuz, S; Pince, S; Hekin, N

    1996-01-01

    Dental environment may be a source of stress for the young patient. Such stressful conditions may provoke fear in anxious children. It is well known that stress produces an activation adrenal steroid secretion. Among the methods for assessing child dental fear, measurement of salivary cortisol level is a simple method, because especially in children, sampling of saliva is easy, and cortisol levels in saliva closely mirror serum free cortisol levels, independent of salivary flow rate. For this study, the salivary cortisol levels of 8 children (mean age 5.6 yr) were measured receiving initial dental treatment. Saliva samples were collected via cotton rolls placed to the floor of the mouth at four stages; prior to treatment, during cavitation, placement of the liner and the restoration. Statistical comparison of the results were done by Student-t test. The increase in salivary cortisol levels during cavitation at the first and secondary appointments were significant (p<0.01 and p<0.05), but not at the second. The other comparisons were not statistically significant (p>0.05). The results of this study suggest that in restorative procedures, mostly it is the cavitation step that creates stress and anxiety in children. Knowledge of the most stressful condition may be helpful for the dentist to prepare the child to treatment steps.

  18. Eighteenth and nineteenth century dental restoration, treatment and consequences in a British nobleman.

    PubMed

    Cox, M; Chandler, J; Boyle, A; Kneller, P; Haslam, R

    2000-12-01

    This paper examines unusual eighteenth and nineteenth century dental treatment and its consequences, in a nobleman excavated from beneath St. Nicholas' Church, Sevenoaks, Kent, UK in the early 1990s. This rare archaeological case exhibits erosion of dental enamel on the labial surface of all the anterior dentition. A programme of historical research suggests that this might be attributed to the application of an acid-based dental tincture or the use of an abrasive substance to whiten the teeth. Palliative treatment for the consequence of this application was prescribed by Dr Robert Blake of Dublin. Further, it bears witness to three dental restorations, two of gold and one tin. The two gold (foil) fillings are an occlusal in the upper-right second molar and a cervical on the labial surface of the upper left canine. The tin filling is an occlusal in the upper left second molar. Excavation of the carious tissue appears to have been undertaken using a spoon shaped implement.

  19. New Design for Rapid Prototyping of Digital Master Casts for Multiple Dental Implant Restorations

    PubMed Central

    Romero, Luis; Jiménez, Mariano; Espinosa, María del Mar; Domínguez, Manuel

    2015-01-01

    Aim This study proposes the replacement of all the physical devices used in the manufacturing of conventional prostheses through the use of digital tools, such as 3D scanners, CAD design software, 3D implants files, rapid prototyping machines or reverse engineering software, in order to develop laboratory work models from which to finish coatings for dental prostheses. Different types of dental prosthetic structures are used, which were adjusted by a non-rotatory threaded fixing system. Method From a digital process, the relative positions of dental implants, soft tissue and adjacent teeth of edentulous or partially edentulous patients has been captured, and a maser working model which accurately replicates data relating to the patients oral cavity has been through treatment of three-dimensional digital data. Results Compared with the conventional master cast, the results show a significant cost savings in attachments, as well as an increase in the quality of reproduction and accuracy of the master cast, with the consequent reduction in the number of patient consultation visits. The combination of software and hardware three-dimensional tools allows the optimization of the planning of dental implant-supported rehabilitations protocol, improving the predictability of clinical treatments and the production cost savings of master casts for restorations upon implants. PMID:26696528

  20. Eighteenth and nineteenth century dental restoration, treatment and consequences in a British nobleman.

    PubMed

    Cox, M; Chandler, J; Boyle, A; Kneller, P; Haslam, R

    2000-12-01

    This paper examines unusual eighteenth and nineteenth century dental treatment and its consequences, in a nobleman excavated from beneath St. Nicholas' Church, Sevenoaks, Kent, UK in the early 1990s. This rare archaeological case exhibits erosion of dental enamel on the labial surface of all the anterior dentition. A programme of historical research suggests that this might be attributed to the application of an acid-based dental tincture or the use of an abrasive substance to whiten the teeth. Palliative treatment for the consequence of this application was prescribed by Dr Robert Blake of Dublin. Further, it bears witness to three dental restorations, two of gold and one tin. The two gold (foil) fillings are an occlusal in the upper-right second molar and a cervical on the labial surface of the upper left canine. The tin filling is an occlusal in the upper left second molar. Excavation of the carious tissue appears to have been undertaken using a spoon shaped implement. PMID:11132689

  1. Translucency of human teeth and dental restorative materials and its clinical relevance

    NASA Astrophysics Data System (ADS)

    Lee, Yong-Keun

    2015-04-01

    The purpose was to review the translucency of human teeth and related dental materials that should be considered for the development of esthetic restorative materials. Translucency is the relative amount of light transmission or diffuse reflection from a substrate surface through a turbid medium. Translucency influences the masking ability, color blending effect, and the degree of light curing through these materials. Regarding the translucency indices, transmission coefficient, translucency parameter, and contrast ratio have been used, and correlations among these indices were confirmed. Translucency of human enamel and dentine increases in direct proportion to the wavelength of incident light in the visible light range. As for the translucency changes by aging, limited differences were reported in human dentine, while those for enamel proved to increase. There have been studies for the adjustment of translucency in dental esthetic restorative materials; the size and amount of filler and the kind of resin matrix were modified in resin composites, and the kind of ingredient and the degree of crystallization were modified in ceramics. Based on the translucency properties of human enamel and dentine, those of replacing restorative materials should be optimized for successful esthetic rehabilitation. Biomimetic simulation of the natural tooth microstructure might be a promising method.

  2. Translucency of human teeth and dental restorative materials and its clinical relevance.

    PubMed

    Lee, Yong-Keun

    2015-04-01

    The purpose was to review the translucency of human teeth and related dental materials that should be considered for the development of esthetic restorative materials. Translucency is the relative amount of light transmission or diffuse reflection from a substrate surface through a turbid medium. Translucency influences the masking ability, color blending effect, and the degree of light curing through these materials. Regarding the translucency indices, transmission coefficient, translucency parameter, and contrast ratio have been used, and correlations among these indices were confirmed. Translucency of human enamel and dentine increases in direct proportion to the wavelength of incident light in the visible light range. As for the translucency changes by aging, limited differences were reported in human dentine, while those for enamel proved to increase. There have been studies for the adjustment of translucency in dental esthetic restorative materials; the size and amount of filler and the kind of resin matrix were modified in resin composites, and the kind of ingredient and the degree of crystallization were modified in ceramics. Based on the translucency properties of human enamel and dentine, those of replacing restorative materials should be optimized for successful esthetic rehabilitation. Biomimetic simulation of the natural tooth microstructure might be a promising method.

  3. Anterior composite restorations in clinical practice: findings from a survey with general dental practitioners

    PubMed Central

    DEMARCO, Flávio Fernando; BALDISSERA, Rudimar Antonio; MADRUGA, Francine Cardozo; SIMÕES, Roberto Cuchiara; LUND, Rafael Guerra; CORREA, Marcos Britto; CENCI, Maximiliano Sergio

    2013-01-01

    Objectives The aim of this study was to assess technical preferences of general dental practitioners when restoring anterior composite restorations. How the level of clinical experience or post-graduate training infuenced their options was also tested. Material and Methods A cross-sectional study was performed using a questionnaire with general dental practitioners (GDPs) (n=276) in Southern Brazil. Information regarding post graduation training (specialization, master's or PhD degree) and linical experience (years since completing graduation) were gathered. The options regarding anterior composite restorations (type of composite, adhesive system, light curing unit, polishing procedures and rubber dam use) were collected. Data were submitted to descriptive analysis and associations were tested. Results Response rate was 68% (187). GDPs selected microhybrid composite (52%) and 2-step total etch adhesive system (77%). LED was the preferred method of activation for 72.8%. Immediate polishing was preferred by 75%, using a combination of techniques. Most of the respondents (74.3%) did not use rubber dam. More experienced clinicians used more halogen lights (p<0.022), performed more light monitoring (p<0.001) and were resistant to use rubber dam (p<0.012). Dentists with post-graduation training used 3-etch-and-rinse system more frequently (p<0.04), usually monitored light intensity (p<0.014) and placed rubber dam more frequently (p<0.044). Conclusions Hybrid composite, simplifed adhesives, LED units and immediate polishing were preferred by Southern Brazilian dentists for anterior composite restorations. Few dentists used rubber dam to perform composite restorations in anterior teeth. Clinical experience and post-graduation training infuenced the dentists' choices. PMID:24473714

  4. Need for informed consent for dentists who use mercury amalgam restorative material as well as technical considerations in removal of dental amalgam restorations.

    PubMed

    Edlich, Richard F; Greene, Jill Amanda; Cochran, Amy A; Kelley, Angela R; Gubler, K Dean; Olson, Brianna M; Hudson, Mary Anne; Woode, Dayna R; Long, William B; McGregor, Walter; Yoder, Carolyn; Hopkins, Debra B; Saepoff, Jessica P

    2007-01-01

    Amalgam restorative material generally contains 50% mercury (Hg) in a complex mixture of copper, tin, silver, and zinc. It has been well documented that this mixture continually emits mercury vapor, which is dramatically increased by chewing, eating, brushing, and drinking hot liquids. Mercury has been demonstrated to have damaging effects on the kidney, central nervous system, and cardiovascular system, and has been implicated in gingival tattoos. While mercury amalgams may result in detrimental exposure to the patient, they can also be a danger in dental practices. In Europe, the federal governments of Norway, Finland, Denmark, and Sweden have enacted legislation requiring that dental patients receive informed consent information about the dental restorative material that will be used. In the United States, a few state governments have enacted informed consent legislation for dental patients receiving dental restorations. These state legislations were enacted by Maine, California, Connecticut, and Vermont. It is a sad tragedy that mercury is causing such health damage to many people. The American Dental Association has said for the past 150 years that the mercury in amalgam is safe and does not leak; however, no clinical studies were ever done and the Food and Drug Administration approved amalgam under a grandfather clause. Subsequent studies have shown this claim of safety not to be true. Over ten years ago, the Federation of American Societies for Experimental Biology Journal published a comprehensive article calling mercury restorative material a major source of mercury exposure to the U.S. population. The authors of this paper recommend that federal and state legislation be passed throughout our country to ensure that consent forms are given to patients receiving silver-mercury amalgam restorative material.

  5. Sociodemographic, Socio-economic, Clinical and Behavioural Factors Modifying Experience and Prevalence of Dental Caries in the Permanent Dentition

    PubMed Central

    Herrera, MS; Medina-Solis, CE; Islas-Granillo, H; Lara-Carrillo, E; Scougall-Vilchis, RJ; Escoffié-Ramírez, M; la Rosa-Santillana, R De; Avila-Burgos, L

    2014-01-01

    ABSTRACT Objective: To identify the sociodemographic, socio-economic, clinical and behavioural factors that modify the experience of decayed, missing and filled teeth (DMFT) and caries prevalence in Nicaraguan children 9-12 years old. Subjects and Methods: We conducted a cross-sectional study in 800 school children 9-12 years old in the city of León, Nicaragua. The clinical oral examinations to identify caries experience were undertaken by two trained and certified examiners. Sociodemographic, socio-economic and behavioural data were collected using questionnaires. Negative binomial regression (NBR) and binary logistic regression (BLR) models were used to model caries experience and caries prevalence, respectively. Results: Mean DMFT index was 0.98 ± 1.74 and caries prevalence (DMFT > 0) was 37.9%. In the NBR model, the categories that increase the expected DMFT mean were: older age, female gender, presence of plaque, and if the school children received curative and curative/preventive dental care in the last year. In the BLR model, the odds of presenting with caries in the permanent dentition were increased in older children, those from large families, mothers with a positive dental attitude, and those school children who received curative and curative/preventive dental care in the last year. Conclusions: Using different models, we identified several sociodemographic, socio-economic, clinical and behavioural factors that modify the experience (NBR) and prevalence (BLR) of dental caries. PMID:25867561

  6. Management of dental trauma to a developing permanent tooth during endotracheal intubation

    PubMed Central

    Sowmya, B; Raghavendra, P

    2011-01-01

    Anesthesiologists consistently work in the mouth of patients but are not exposed to comprehensive education of teeth, the surrounding structures, and intraoral prosthesis. One of the most common adverse events related to anesthesia is perioperative dental damage. To minimize these dental injuries, a preoperative assessment of patient's dentition and intra-oral tissues should be undertaken. PMID:21772697

  7. Investigation of the electrical properties of some dental composite restorative materials before and after laser exposure.

    PubMed

    ElKestawy, M A; Saafan, S A; Shehata, M M; Saafan, A M

    2006-10-01

    Some electrical properties, such as piezoelectricity, ac conductivity, dielectric constant and loss tangent of nine commercial types of dental composite restorative materials, have been investigated before and after laser exposure for 3s to study the effect of a probable laser exposure during some surgeries on the electrical properties of these materials. No piezoelectric effect has been found in these materials before and after laser exposure. The materials were found to be good insulators (very poorly conducting materials). The temperature and frequency dependence of ac conductivity, dielectric constant and loss tangent have not shown significant changes in values after laser exposure.

  8. A prospective study of the survival of chemically activated anterior resin composite restorations in general dental practice: 5-year results.

    PubMed

    van Noort, R; Davis, L G

    1993-08-01

    The principals of 26 general dental practices agreed to use six chemically activated resin composite restorative materials to restore Class III and Class V lesions and record information concerning their performance over a period of 5 years. The information collected was analysed by actuarial methods to assess the clinical longevity and reasons for replacement as perceived by the dentists operating in the General Dental Service in England. At the end of 5 years, 14 dentists provided sufficient returns for their data to be considered suitable for analysis. The database consisted of 2399 Class III and 1093 Class V restorations. The overall probability of survival at 5 years of Class III and Class V restorations was 62.9% and 71.8% respectively. The difference in performance between the six restorative materials was small, with the probability of survival varying from 70.4 +/- 2.9% to 56.3 +/- 2.9% for the Class III restorations and 78.6 +/- 3.7% to 67.7 +/- 4.2% for the Class V restorations. The main reasons for replacement were general surface discoloration, secondary caries and fracture. The chemically activated composite restorative materials available at the time of initiating this study produced comparable performances in general dental practice when used without enamel and dentine bonding techniques. This suggests that more general practice-based clinical studies are needed to determine whether or not improvements in materials and techniques are effectively transferred to the general practice situation.

  9. Behaviour of general dental practitioners in Germany regarding posterior restorations with flowable composites.

    PubMed

    Seemann, Rainer; Pfefferkorn, Frank; Hickel, Reinhard

    2011-10-01

    Because the recommendation to use flowables for posterior restorations is still a matter of debate, the objective of this study was to determine in a nationwide survey in Germany how frequently, for what indications, and for what reasons, German dentists use flowable composites in posterior teeth. In addition, the acceptance of a simplified filling technique for posterior restorations using a low stress flowable composite was evaluated. Completed questionnaires from all over Germany were returned by 1,449 dentists resulting in a response rate of 48.5%; 78.6% of whom regularly used flowable composites for posterior restorations. The most frequent indications were cavity lining (80.1%) and small Class I fillings (74.2%). Flowables were less frequently used for small Class II fillings (22.7%) or other indications (13.6%). Most frequent reasons given for the use of flowables in posterior teeth were the prevention of voids (71.7%) and superior adaptation to cavity walls (72.9%), whereas saving time was considered less important (13.8%). Based on the subjective opinion of the dentists the simplified filling technique seemed to deliver advantages compared to the methods used to date particularly with regard to good cavity adaptation and ease of use. In conclusion, resin composites are the standard material type used for posterior restorations by general dental practitioners in Germany and most dentists use flowable composites as liners.

  10. Evaluation of marginal failures of dental composite restorations by acoustic emission analysis.

    PubMed

    Gu, Ja-Uk; Choi, Nak-Sam

    2013-01-01

    In this study, a nondestructive method based on acoustic emission (AE) analysis was developed to evaluate the marginal failure states of dental composite restorations. Three types of ring-shaped substrates, which were modeled after a Class I cavity, were prepared from polymethyl methacrylate, stainless steel, and human molar teeth. A bonding agent and a composite resin were applied to the ring-shaped substrates and cured by light exposure. At each time-interval measurement, the tooth substrate presented a higher number of AE hits than polymethyl methacrylate and steel substrates. Marginal disintegration estimations derived from cumulative AE hits and cumulative AE energy parameters showed that a signification portion of marginal gap formation was already realized within 1 min at the initial light-curing stage. Estimation based on cumulative AE energy gave a higher level of marginal failure than that based on AE hits. It was concluded that the AE analysis method developed in this study was a viable approach in predicting the clinical survival of dental composite restorations efficiently within a short test period.

  11. Strength and fatigue performance versus filler fraction of different types of direct dental restoratives.

    PubMed

    Lohbauer, Ulrich; Frankenberger, Roland; Krämer, Norbert; Petschelt, Anselm

    2006-01-01

    The aim of this study was to evaluate the mechanical properties, such as Young's moduli, fracture strengths (FS), and flexural fatigue limits of todays resin composite dental restoratives. All materials have been subdivided into flowable, aesthetic hybrid and nano-filled hybrid composites as marketed by dental manufacturers and analyzed in terms of the actual filler configurations. Specimen bars have been manufactured in reference to ISO 4049 standard, light-cured for 20 s, and stored in distilled water before testing. The elastic moduli (EM), FS, and flexural fatigue limits (FFL) were measured after 14 days storage by using the four-point bending test. The FFL was determined for 10(4) cycles. The fatigue data were analyzed by using the "staircase" approach and statistically treated by ANOVA analysis. Flowable materials with a reduced filler content exhibited the lowest Young's moduli, compared with those measured for higher filled materials. A linear relationship has been found between elastic moduli and filler loading (r(2) = 0.798). Correlations of FS and fatigue data to different filler fractions could not be proved. FS ranged between 61.3 and 124.9 MPa. After 10(4) cycles of fatigue loading, the FS suffered from a decrease between 45.2 and 61.7%. However, materials providing high initial strengths do not obviously reveal the best fatigue resistance. A marketing-based grouping of direct restorative materials has no meaning toward laboratory testing of mechanical properties.

  12. Association between nutritional status and dental caries in permanent dentition among primary schoolchildren aged 12-14 years, Thailand.

    PubMed

    Narksawat, Kulaya; Tonmukayakul, Utsana; Boonthum, Angsana

    2009-03-01

    This cross-sectional study assessed associations between nutrition and dental caries in permanent dentition and identified oral hygiene indicators among older children aged 12-14 years in primary schools in Thailand. The study was comprised of 862 schoolchildren from five provinces representing five regions of Thailand, from both rural and urban areas, including Bangkok. The dental hygeine status was assessed by evaluating for decayed teeth, missing teeth due to decay, and filled teeth index (DMFT index). Weight and height were measured to evaluate the nutritional status; hygiene practices assessed by interview. The results show a negative relationship between nutritional status and the DMFT index, which increased when the nutritional status decreased (Spearman's rho correlation = -0.140, p < 0.001). The results from multiple logistic regression analysis showed normal weight and thin schoolchildren were more likely to have a DMFT of at least 1 by 1.94 times (OR = 1.94; 95%CI = 1.25-3.00, p = 0.004) and 2.22 times (OR = 2.22; 95%CI = 1.20-4.09, p = 0.001), respectively, compared to overweight and obese children. Normal and thin schoolchildren had a higher risk for dental caries than overweight and obese children aged 12-14 years in Thailand. School health promotion activities should emphasize eating habit improvement in order to reduce the incidence of caries.

  13. Accuracy of intraoral and extraoral digital data acquisition for dental restorations

    PubMed Central

    Rudolph, Heike; Salmen, Harald; Moldan, Matthias; Kuhn, Katharina; Sichwardt, Viktor; Wöstmann, Bernd; Luthardt, Ralph Gunnar

    2016-01-01

    ABSTRACT The computer-aided design (CAD) and computer-aided manufacturing (CAM) process chain for dental restorations starts with taking an impression of the clinical situation. For this purpose, either extraoral digitization of gypsum models or intraoral digitization can be used. Despite the increasing use of dental digitizing systems, there are only few studies on their accuracy. Objective This study compared the accuracy of various intraoral and extraoral digitizing systems for dental CAD/CAM technology. Material and Methods An experimental setup for three-dimensional analysis based on 2 prepared ceramic master dies and their corresponding virtual CAD-models was used to assess the accuracy of 10 extraoral and 4 intraoral optical non-contact dental digitizing systems. Depending on the clinical procedure, 10 optical measurements of either 10 duplicate gypsum dies (extraoral digitizing) or directly of the ceramic master dies (intraoral digitizing) were made and compared with the corresponding CAD-models. Results The digitizing systems showed differences in accuracy. However, all topical systems were well within the benchmark of ±20 µm. These results apply to single tooth measurements. Conclusions Study results are limited, since only single teeth were used for comparison. The different preparations represent various angles and steep and parallel opposing tooth surfaces (incisors). For most digitizing systems, the latter are generally the most difficult to capture. Using CAD/CAM technologies, the preparation angles should not be too steep to reduce digitizing errors. Older systems might be limited to a certain height or taper of the prepared tooth, whereas newer systems (extraoral as well as intraoral digitization) do not have these limitations. PMID:27008261

  14. Dental arch size in healthy human permanent dentitions: ethnic differences as assessed by discriminant analysis.

    PubMed

    Ferrario, V F; Sforza, C; Colombo, A; Carvajal, R; Duncan, V; Palomino, H

    1999-01-01

    Race and ethnicity variably influence the form of the human craniofacial complex. In the present study, the effects of ethnicity and sex on the global size of normal adult dental arches were analyzed. The dental arches of 47 northern Chilean mestizos (25 men, 22 women) and 95 northern Italian Caucasians (50 men, 45 women) were cast in stone. All subjects had a complete dentition in both arches. In all models the coordinates of dental cusp tips were digitized using an image analyzer. The center of gravity of each tooth was computed and arches were interpolated using a polynomial model (y = ax + bx2 + cx3 + dx4). In all arches, the intercanine, intermolar, and mid-intercanine to mid-intermolar distances were computed from the dental centers of gravity. These arch distances were entered in a linear discriminant function analysis. The polynomial model accurately interpolated data points in all instances, and most of the dental arch form was determined by the first and second degree coefficients. On average, Italian Caucasian arches were smaller than Chilean mestizo arches. Male mean distances were larger than female distances regardless of ethnic group or arch. The linear discriminant analysis performed between male and female arches within ethnic groups was significant only for both Italian Caucasian arches, but the percentage errors for the classification of a new individual were very high (about 30%). Conversely, Italian Caucasian arches could always be discriminated from Chilean mestizo arches of the same sex with a much smaller error.

  15. Matching the optical properties of direct esthetic dental restorative materials to those of human enamel and dentin

    NASA Astrophysics Data System (ADS)

    Ragain, James Carlton, Jr.

    One of the goals of the restorative dentist is to restore the appearance of the natural dentition. Clinical matching of teeth and restorative materials are seldom accurate and shade selection techniques are subjective. The first specific aim of this research was to characterize the optical absorption and scattering that occurs within enamel, dentin, and composite resin and compomer restorative materials and to relate those phenomena to translucency and color. The second aim was to evaluate small color differences among composite restorative materials which would be detectable by humans. The last aim was to lay the foundation for developing an improved model of specifying layers of dental restorative materials in order to match the translucency and color to those of human enamel. The Kubelka-Munk theory was validated for enamel, dentin, and the restorative materials. These tissues and materials were then characterized in terms of their color parameters. Tooth cores were also characterized in terms of color space parameters. Human subjects were evaluated for their abilities to discriminate small color differences in the dental composite resin materials. The following conclusions were derived from this study: (1) Kubelka-Munk theory accurately predicts the diffuse reflectance spectra of enamel, dentin, and the direct esthetic dental restorative materials studied. (2) Scattering and absorption coefficients of the dental tissues and esthetic restorative materials can be directly calculated from diffuse reflectance measurements of a uniformly thick slab of tissue/material using black and white backings and the appropriate refractive index. (3) For tooth cores, there is a positive correlation between L* and b* and a negative correlation between L* and a*. (4) The range of translucency parameters for the restorative materials studied does not match those of enamel and dentin. (5) None of the shades of the dental composite resin restorative materials studied fit into the

  16. Chemical or microbiological models of secondary caries development around different dental restorative materials.

    PubMed

    Lobo, Maristela M; Gonçalves, Reginaldo B; Ambrosano, Gláucia Maria B; Pimenta, Luiz André F

    2005-08-01

    This study evaluated artificial secondary caries around restorative materials, induced by means of chemical or microbiological models. The following materials were used randomly to restore 130 dental blocks: (1) zinc-oxide eugenol-free temporary filling: Coltosol (Coltène/Whaledent Inc.; n = 30), (2) silver amalgam: Permite C (SDI Limited, n = 20), (3) composite resin: Filtek Z250 (3M ESPE; n = 20), (4) glass-ionomer cement: Fuji II (GC America Inc.; n = 20), (5) resin-modified glass ionomer: Vitremer (3M ESPE; n = 20), and (6) polyacid modified resin: Dyract AP (Dentsply; n = 20). Ten specimens of Group 1 were kept in humidity, and had no carious formation (NC). Ten specimens of each group were submitted to pH cycling (CG, n = 60), and the others were immersed in a medium containing Streptococcus mutans and sucrose (BG, n = 60). Mineral content was determined by microhardness assessment, and lesion depth was measured in polarized light photomicrographs. In the chemical model (CG), mineral content values in the vicinities of restoration were high for Groups 5 (75.7 +/- 11.9), 4 (70.8 +/- 14.2), and NC (95.4 +/- 3.8); intermediate for Groups 1 (55.8 +/- 18.5), 6 (45.6 +/- 11.0), and 2 (44.3 +/- 11.2); and reduced for Group 3 (34.7 +/- 9.7). In the microbiological model (BG), results were similar to CG, although there was less demineralization. The highest lesion depths were found for Groups 3 (182.3 +/- 33.2) in CG and 6 (126.5 +/- 42.8) in BG, when compared to Group 5 (114.6 +/- 26.0 and 56.2 +/- 33.2, respectively). In both models of caries induction, ionomeric materials showed a superior cariostatic effect when compared to the other restorative materials.

  17. Contraction behaviors of dental composite restorations--finite element investigation with DIC validation.

    PubMed

    Chuang, Shu-Fen; Chang, Chih-Han; Chen, Terry Yuan-Fang

    2011-11-01

    The objective of this study was to examine the effects of cavity configuration on the polymerization shrinkage and stress of light-cured composite restorations by combining local strain measurement and a finite element analysis (FEA). Dental mesio-occluso-distal cavities of various widths and depths (each for 2 vs. 4 mm), representing different configuration factors, were prepared on extracted molars. The displacements of the bonded tooth cusps and cavity floors, caused by polymerization shrinkage of composite restorations, were assessed utilizing a digital-image-correlation (DIC) technique. The cervical marginal microleakage was investigated by examining the resin replicas of these restorations under SEM. The local material properties of the polymerized composite along the curing depth were defined by the nanoindentation test and applied in the subsequent FEA. In the FEA, four models were generated to correspond with the experimental restorations. In the DIC measurement results, the 4(w)×4(D) mm cavity presented the greatest values of inward displacements at the cusp and floor. The cavity depth, rather than the cavity width, was found to significantly correlate to the floor deformation, the location of shrinkage centers, and also the cervical microleakage ratio. The FEA simulation results showed that the 2(w)×4(D) mm cavity presented the maximal von Mises and principal stress located respectively on the cervical margins and cavity floor. Additional safety factor analysis showed a high risk of bond failure over the cavity floor in the 4-mm deep cavity. With the experimental validation, the simulation revealed that the cavity depth was significant to the formation of contraction stress and the incidence of interfacial debonding. PMID:22098914

  18. Contraction behaviors of dental composite restorations--finite element investigation with DIC validation.

    PubMed

    Chuang, Shu-Fen; Chang, Chih-Han; Chen, Terry Yuan-Fang

    2011-11-01

    The objective of this study was to examine the effects of cavity configuration on the polymerization shrinkage and stress of light-cured composite restorations by combining local strain measurement and a finite element analysis (FEA). Dental mesio-occluso-distal cavities of various widths and depths (each for 2 vs. 4 mm), representing different configuration factors, were prepared on extracted molars. The displacements of the bonded tooth cusps and cavity floors, caused by polymerization shrinkage of composite restorations, were assessed utilizing a digital-image-correlation (DIC) technique. The cervical marginal microleakage was investigated by examining the resin replicas of these restorations under SEM. The local material properties of the polymerized composite along the curing depth were defined by the nanoindentation test and applied in the subsequent FEA. In the FEA, four models were generated to correspond with the experimental restorations. In the DIC measurement results, the 4(w)×4(D) mm cavity presented the greatest values of inward displacements at the cusp and floor. The cavity depth, rather than the cavity width, was found to significantly correlate to the floor deformation, the location of shrinkage centers, and also the cervical microleakage ratio. The FEA simulation results showed that the 2(w)×4(D) mm cavity presented the maximal von Mises and principal stress located respectively on the cervical margins and cavity floor. Additional safety factor analysis showed a high risk of bond failure over the cavity floor in the 4-mm deep cavity. With the experimental validation, the simulation revealed that the cavity depth was significant to the formation of contraction stress and the incidence of interfacial debonding.

  19. Heat generation caused by ablation of dental restorative materials with an ultra short pulse laser (USPL) system

    NASA Astrophysics Data System (ADS)

    Braun, Andreas; Wehry, Richard; Brede, Olivier; Frentzen, Matthias; Schelle, Florian

    2011-03-01

    The aim of this study was to assess heat generation in dental restoration materials following laser ablation using an Ultra Short Pulse Laser (USPL) system. Specimens of phosphate cement (PC), ceramic (CE) and composite (C) were used. Ablation was performed with an Nd:YVO4 laser at 1064 nm and a pulse length of 8 ps. Heat generation during laser ablation depended on the thickness of the restoration material. A time delay for temperature increase was observed in the PC and C group. Employing the USPL system for removal of restorative materials, heat generation has to be considered.

  20. Intraoral corrosion resulting from coupling dental implants and restorative metallic systems.

    PubMed

    Lemons, J E; Lucas, L C; Johansson, B I

    1992-01-01

    Materials used for the construction of dental restorations and implants include a wide range of metals and alloys, ceramics and carbons, and polymers. When metals and alloys are placed in direct contact in the oral cavity, a galvanic cell can be formed that may compromise the longevity of one or more of the materials in the couple. In vitro electrochemical corrosion analyses have proven to be a valuable tool for providing guidance on the selection of metallic materials. These analyses can provide basic data on electrochemical potentials, current rates, and the evaluation of galvanic corrosion conditions. This article seeks to provide the clinician with information that can be valuable in the selection of metallic materials that may be placed in direct contact with one another in the oral cavity.

  1. Non-thermal atmospheric plasmas in dental restoration: improved resin adhesive penetration

    PubMed Central

    Zhang, Ying; Yu, Qingsong; Wang, Yong

    2014-01-01

    Objective To investigate the influence of non-thermal plasma treatment on the penetration of a model dental adhesive into the demineralized dentin. Methods Prepared dentin surfaces were conditioned with Scotchbond Universal etchant for 15 s and sectioned equally perpendicular to the etched surfaces. The separated halves were randomly selected for treatment with an argon plasma brush (input current 6 mA, treatment time 30 s) or gentle argon air blowing (treatment time 30 s, as control). The plasma-treated specimens and control specimens were applied with a model adhesive containing 2,2-bis[4-(2-hydroxy-3-methacryloxypropoxy) phenyl]-propane (BisGMA) and 2-hydroxyethyl methacrylate (HEMA) (mass ratio of 30/70), gently air-dried for 5 s, and light-cured for 20 s. Cross-sectional specimens were characterized using micro-Raman spectral mapping across the dentin, adhesive/dentin interface, and adhesive layer at 1∼micron spatial resolution. SEM was also employed to examine the adhesive/dentin interfacial morphology. Results The micro-Raman result disclosed that plasma treatment significantly improved the penetration of the adhesive, evidenced by the apparently higher content of the adhesive at the adhesive/dentin interface as compared to the control. Specifically, the improvement of the adhesive penetration using plasma technique was achieved by dramatically enhancing the penetration of hydrophilic monomer (HEMA), while maintaining the penetration of hydrophobic monomer (BisGMA). Morphological observation at the adhesive/dentin interface using SEM also confirmed the improved adhesive penetration. The results further suggested that plasma treatment could benefit polymerization of the adhesive, especially in the interface region. Conclusion The significant role of the non-thermal plasma brush in improving the adhesive penetration into demineralized dentin has been demonstrated. The results obtained may offer a better prospect of using plasma in dental restoration to

  2. Effectiveness of benzocaine in reducing deep cavity restoration and post-extraction stress in dental patients

    PubMed Central

    Al-Samadani, Khalid H.; Gazal, Giath

    2015-01-01

    Objectives: To investigate the effectiveness of topical anesthetic, 20% benzocaine in relieving pain and stress in patients following deep cavity restoration and extraction of teeth under local anesthesia (LA). Methods: A prospective clinical trial was conducted from October 2014 until April 2015 at Taibah University, Al Madinah Al Munawarah, Kingdom of Saudi Arabia. Forty-five patients were included in the 20% benzocaine group, and 46 in the normal saline group. Evaluation of the dental stress was made pre-operatively and immediately post-operative treatment using the visual analogue scale (VAS). Furthermore, discomfort of the injections were recorded by the patients after each treatment on standard 100 mm VAS, tagged at the endpoints with “no pain” (0 mm) and “unbearable pain” (100 mm). Results: There were statistically significant differences between the mean stress scores for patients in the benzocaine and normal saline groups post-operatively (p=0.002). There were significant differences between the mean pain scores for patients in the post buccal injection (p=0.001), post palatal injection (p=0.01), and the post inferior alveolar nerve block groups (p=0.02). Buccal, palatal, and inferior alveolar nerve block injections were more painful for patients in the normal saline group than the benzocaine group. Conclusion: This investigation has demonstrated that post-operative stress associated with deep cavity restoration and dental extractions under LA can be reduced by the application of topical anesthetic (20% benzocaine) at the operative site for intra-oral injections. PMID:26593169

  3. Clinical practice guidelines for recall and maintenance of patients with tooth-borne and implant-borne dental restorations.

    PubMed

    Bidra, Avinash S; Daubert, Diane M; Garcia, Lily T; Kosinski, Timothy F; Nenn, Conrad A; Olsen, John A; Platt, Jeffrey A; Wingrove, Susan S; Chandler, Nancy Deal; Curtis, Donald A

    2016-01-01

    The purpose of this article is to provide guidelines for patient recall regimen, professional maintenance regimen, and at-home maintenance regimen for patients with tooth-borne and implant-borne removable and fixed restorations. The American College of Prosthodontists (ACP) convened a scientific panel of experts appointed by the ACP, American Dental Association, Academy of General Dentistry, and American Dental Hygienists Association, who critically evaluated and debated recently published findings from 2 systematic reviews on this topic. The major outcomes and consequences considered during formulation of the clinical practice guidelines (CPGs) were risk for failure of tooth- and implant-borne restorations. The panel conducted a roundtable discussion of the proposed guidelines, which were debated in detail. Feedback was used to supplement and refine the proposed guidelines, and consensus was attained. A set of CPGs was developed for tooth-borne restorations and implant-borne restorations. Each CPG comprised (1) patient recall, (2) professional maintenance, and (3) at-home maintenance. For tooth-borne restorations, the professional maintenance and at-home maintenance CPGs were subdivided for removable and fixed restorations. For implant-borne restorations, the professional maintenance CPGs were subdivided for removable and fixed restorations and further divided into biological maintenance and mechanical maintenance for each type of restoration. The at-home maintenance CPGs were subdivided for removable and fixed restorations. The clinical practice guidelines presented in this document were initially developed using the 2 systematic reviews. Additional guidelines were developed using expert opinion and consensus, which included discussion of the best clinical practices, clinical feasibility, and risk-benefit ratio to the patient. To the authors' knowledge, these are the first CPGs addressing patient recall regimen, professional maintenance regimen, and at

  4. Ultrashort pulse laser processing of hard tissue, dental restoration materials, and biocompatibles

    NASA Astrophysics Data System (ADS)

    Yousif, A.; Strassl, M.; Beer, F.; Verhagen, L.; Wittschier, M.; Wintner, E.

    2007-07-01

    During the last few years, ultra-short laser pulses have proven their potential for application in medical tissue treatment in many ways. In hard tissue ablation, their aptitude for material ablation with negligible collateral damage provides many advantages. Especially teeth representing an anatomically and physiologically very special region with less blood circulation and lower healing rates than other tissues require most careful treatment. Hence, overheating of the pulp and induction of microcracks are some of the most problematic issues in dental preparation. Up till now it was shown by many authors that the application of picosecond or femtosecond pulses allows to perform ablation with very low damaging potential also fitting to the physiological requirements indicated. Beside the short interaction time with the irradiated matter, scanning of the ultra-short pulse trains turned out to be crucial for ablating cavities of the required quality. One main reason for this can be seen in the fact that during scanning the time period between two subsequent pulses incident on the same spot is so much extended that no heat accumulation effects occur and each pulse can be treated as a first one with respect to its local impact. Extension of this advantageous technique to biocompatible materials, i.e. in this case dental restoration materials and titanium plasma-sprayed implants, is just a matter of consequence. Recently published results on composites fit well with earlier data on dental hard tissue. In case of plaque which has to be removed from implants, it turns out that removal of at least the calcified version is harder than tissue removal. Therefore, besides ultra-short lasers, also Diode and Neodymium lasers, in cw and pulsed modes, have been studied with respect to plaque removal and sterilization. The temperature increase during laser exposure has been experimentally evaluated in parallel.

  5. Effect of curing with a plasma light on the properties of polymerizable dental restorative materials.

    PubMed

    Millar, B J; Nicholson, J W

    2001-06-01

    Specimens of light-curable dental restoratives have been prepared using either a conventional dental curing lamp (for 20 or 30 s) or a plasma light (for 1 or 2 s). The specimens were then stored in water until their mass equilibrated, then dried to constant mass. Most specimens lost material in this process but the losses in all specimens cured with the plasma light were significantly greater than those cured with the conventional lights (P < 0.05). Longer cure times gave slightly reduced losses in water in most cases. The specimens were then returned to water and allowed to re-equilibrate and their equilibrium water uptake determined. There was no simple trend in this latter property because elution of loosely bound hydrophilic species may have resulted in a less hydrophilic specimen, whose equilibrium water content was therefore correspondingly lower. Overall, the losses through dissolution in water suggest that plasma curing is less effective for these materials than conventional light curing, as it probably results in material with lower molar mass. The losses for the resin-modified glass-ionomer were much greater than for other materials, and it was concluded that the more rapid polymerization with plasma light caused a significant inhibitation of the acid-base part of the setting process. These findings suggest that long-term durability of materials may be compromised by employing plasma light cure rather than a conventional cure system and further studies of this point are recommended.

  6. Oral and dental restoration of wide alveolar cleft using distraction osteogenesis and temporary anchorage devices.

    PubMed

    Rachmiel, Adi; Emodi, Omri; Gutmacher, Zvi; Blumenfeld, Israel; Aizenbud, Dror

    2013-12-01

    Closure of large alveolar clefts and restoration by a fixed bridge supported by implants is a challenge in cleft alveolus treatment. A major aesthetic concern with distraction osteogenesis is obtaining a predictable position of the implant in relation to the newly generated bony alveolar ridge. We describe the treatment of a large cleft alveolus and palate reconstruction by distraction osteogenesis utilizing temporary anchorage devices (TADs) followed by a fixed implant-supported bridge. The method consists of segmental bone transport by distraction osteogenesis using a bone-borne distractor to minimize the alveolar cleft, followed by closure of the residual small defect by bone grafting three months later. During the active transport distraction, TADs were used exerting multidirectional forces to control the distraction vector forward and laterally for better interarch relation. A vertical alveolar distraction of the newly reconstructed bone of 15 mm facilitated optimal implant placement. The endosseous implants were osteointegrated and supported a fixed dental prosthesis. In conclusion, the large cleft alveolus defect was repaired in three dimensions by distraction osteogenesis assisted by TADs, and the soft tissues expanded simultaneously. Endosseous implants were introduced in the newly reconstructed bone for a fixed dental prosthesis enabling, rehabilitation of aesthetics, eating and speaking.

  7. Mathematical definition of the shape of dental arches in human permanent healthy dentitions.

    PubMed

    Ferrario, V F; Sforza, C; Miani, A; Tartaglia, G

    1994-08-01

    Dental arch shape was studied in 50 men and 45 women aged 20-27 years with sound dentitions. Maxillary and mandibular arches were reconstructed by a fourth-order polynomial and a 'mixed' elliptical (anterior teeth), plus parabolic (post-canine teeth) interpolation of buccal cusp tips (central incisor to second molar). The maxillary arch resulted wider than the mandibular arch regardless of gender. Gender differences were found especially in the maxillary arch, where they reflect more a size discrepancy than a shape difference. The polynomial interpolation allowed the evaluation of arch asymmetry, which resulted negligible in all the subjects. The elliptical plus parabolic interpolation gave mean plots which were well superimposable to the ones obtained by the polynomial interpolation. These curves are geometrically simple and can be used for the mathematical description of dental arch shape in non-patient subjects. Moreover, they allow separate analysis of teeth with a different functional meaning.

  8. Information system analysis of an e-learning system used for dental restorations simulation.

    PubMed

    Bogdan, Crenguţa M; Popovici, Dorin M

    2012-09-01

    The goal of using virtual and augmented reality technologies in therapeutic interventions simulation, in the fixed prosthodontics (VirDenT) project, is to increase the quality of the educational process in dental faculties, by assisting students in learning how to prepare teeth for all-ceramic restorations. Its main component is an e-learning virtual reality-based software system that will be used for the developing skills in grinding teeth, needed in all-ceramic restorations. The complexity of the domain problem that the software system dealt with made the analysis of the information system supported by VirDenT necessary. The analysis contains the following activities: identification and classification of the system stakeholders, description of the business processes, formulation of the business rules, and modelling of business objects. During this stage, we constructed the context diagram, the business use case diagram, the activity diagrams and the class diagram of the domain model. These models are useful for the further development of the software system that implements the VirDenT information system.

  9. Effects of the Nd:YAG laser on amalgam dental restorative material: a preliminary study

    NASA Astrophysics Data System (ADS)

    Cernavin, Igor; Hogan, Sean P.

    1996-09-01

    The Nd:YAG laser has been marketed as an instrument for use on both hard and soft dental tissues. Its potential for use on hard tissues is limited but it may be the instrument of choice for use in certain soft tissue procedures. The aim of this study was to examine the effects of the Nd:YAG laser on amalgam restorations which frequently occur on tooth surfaces adjacent to areas of soft tissue which may be subjected to the laser. The amalgam used was Tytin. The laser firing was controlled by a computer and a constant repetition rate of 40 Hz was used. Energy per pulse was altered as follows, 30 mJ, 40 mJ, 60 mJ, 80 mJ, 120 mJ and 140 mJ. Exposure times of 0.05 sec, 0.125 sec, 0.25 sec, 0.5 sec, 1 sec, 2 sec, 3 sec, 4 sec, and 5 sec were used. The width of defect was measured using a Nikon measurescope with 10x magnification and it was established that the damage threshold lies between 0.125 sec and 0.25 sec for 30 mJ per pulse. The data was analyzed using a one way ANOVA statistical test. There was a significant correlation between the width of the defect and energy per pulse setting as well as exposure time. The findings indicate that amalgam restorations are prone to damage from inadvertent laser exposure and clinicians must take measures to protect such restorations during lasing of soft tissues.

  10. The effects of the Nd:YAG laser on amalgam dental restorative material.

    PubMed

    Cernavin, I; Hogan, S P

    1999-06-01

    The Nd:YAG laser has been marketed as an instrument for use on both hard and soft dental tissues. Its potential for use on hard tissues is limited but it may be the instrument of choice for use in certain soft tissue procedures. The aim of this study was to examine the effects of the Nd:YAG laser on amalgam restorations which are frequently placed on tooth surfaces adjacent to areas of soft tissue which may be subjected to the laser. The amalgam used was Tytin. The laser firing was controlled by a computer and a constant repetition rate of 40 Hz was used. Energy per pulse was altered as follows: 30 mJ, 40 mJ, 60 mJ, 80 mJ, 120 mJ and 140 mJ. Exposure times of 0.05 s (2 pulses), 0.125 s (5 pulses), 0.25 s (10 pulses), 0.5 s (20 pulses), 1 s (40 pulses), 2 s (80 pulses), 3 s (120 pulses), 4 s (160 pulses), and 5 s (200 pulses) were used. The width of defect was measured using a measuring microscope with 10x magnification and it was established that the damage threshold lies between 0.125 s (5 pulses) and 0.25 s (10 pulses) for 30 mJ per pulse. Scanning electron microscope observations revealed that the melting of amalgam at exposure times of 5 s actually decreased the size of the observed defect. The data were analysed using a two-way ANOVA statistical test. There was a significant (p < 0.001) correlation between the width of the defect and exposure time up to an exposure time of 4 s and the width of defect and the energy per pulse setting. The findings indicate that amalgam restorations are damaged by inadvertent laser exposure and clinicians must take measures to protect such restorations during lasing of soft tissues.

  11. Attitudes of some European dental undergraduate students to the placement of direct restorative materials in posterior teeth.

    PubMed

    Lynch, C D; Guillem, S E; Nagrani, B; Gilmour, A S M; Ericson, D

    2010-12-01

    The aim of this article was to report on the attitudes, opinions and confidences of final year dental students in three European schools towards the restoration of posterior teeth and in particular towards the use of amalgam and resin composite. One hundred and twenty-eight pre-piloted questionnaires were distributed to final year dental students in Cardiff, Dublin and Malmö. The questionnaire sought information relating to various opinions and attitudes towards the use of amalgam and resin composite in posterior teeth. Information was returned anonymously. Ninety-one completed questionnaires were returned (response rate=71%; Cardiff: n =40, Dublin: n=24, Malmö: n=27). Ninety-three per cent of Malmö students (n=24), 67% of Dublin students (n=16) and 60% of Cardiff students (n=24) reported that they feel confident when placing posterior resin composites. One hundred per cent of Malmö students (n=27), 75% of Cardiff students (n=30) and 33% of Dublin students (n=8) would prefer to have a resin composite rather than amalgam, placed in one of their own posterior teeth. Eighty-five per cent of Malmö students (n=23), 30% of Cardiff students (n=12) and 25% of Dublin students (n=6) perceive amalgam as being harmful to the environment. For the restoration of a posterior tooth in a pregnant female, 44% of students (n=40) would place a resin composite restoration, and 7% (n=6) would place an amalgam restoration, while 32% (n=29) would place a temporary restoration. Students at Malmö report that they place more posterior resin composites and have greater confidence at placing posterior resin composites than students at Cardiff or Dublin. There was confusion relating to the choice of restorative materials for pregnant females. Large variations in restorative strategies among graduates must be considered as dental professionals can practice in all countries within the European Union.

  12. Microleakage of Four Dental Cements in Metal Ceramic Restorations With Open Margins

    PubMed Central

    Eftekhar Ashtiani, Reza; Farzaneh, Babak; Azarsina, Mohadese; Aghdashi, Farzad; Dehghani, Nima; Afshari, Aisooda; Mahshid, Minu

    2015-01-01

    Background: Fixed prosthodontics is a routine dental treatment and microleakage is a major cause of its failure. Objectives: The aim of this study was to assess the marginal microleakage of four cements in metal ceramic restorations with adapted and open margins. Materials and Methods: Sixty sound human premolars were selected for this experimental study performed in Tehran, Iran and prepared for full-crown restorations. Wax patterns were formed leaving a 300 µm gap on one of the proximal margins. The crowns were cast and the samples were randomly divided into four groups based on the cement used. Copings were cemented using zinc phosphate cement (Fleck), Fuji Plus resin-modified glass ionomer, Panavia F2.0 resin cement, or G-Cem resin cement, according to the manufacturers’ instructions. Samples were immersed in 2% methylene blue solution. After 24 hours, dye penetration was assessed under a stereomicroscope and analyzed using the respective software. Data were analyzed using ANOVA, paired t-tests, and Kruskal-Wallis, Wilcoxon, and Mann-Whitney tests. Results: The least microleakage occurred in the Panavia F2.0 group (closed margin, 0.18 mm; open margin, 0.64 mm) and the maximum was observed in the Fleck group (closed margin, 1.92 mm; open margin, 3.32 mm). The Fleck group displayed significantly more microleakage compared to the Fuji Plus and Panavia F2.0 groups (P < 0.001) in both closed and open margins. In open margins, differences in microleakage between the Fuji Plus and G-Cem as well as between the G-Cem and Panavia F2.0 groups were significant (P < 0.001). In closed margins, only the G-Cem group displayed significantly more microleakage as compared to the Panavia F2.0 group (P < 0.05). Paired t-test results showed significantly more microleakage in open margins compared to closed margins, except in the Fuji Plus group (P = 0.539). Conclusions: Fuji Plus cement exhibited better sealing ability in closed and open margins compared to G-Cem and Fleck

  13. Survey on the teaching and use in dental schools of resin-based materials for restoring posterior teeth.

    PubMed

    Liew, Zunliang; Nguyen, Edward; Stella, Rita; Thong, Irene; Yip, Natalia; Zhang, Felix; Burrow, Michael F; Tyas, Martin J

    2011-02-01

    A survey was conducted of 100 dental schools worldwide to investigate the current teaching of posterior resin composite restorations. A 20 multi-part question questionnaire was emailed to the selected schools. Schools were selected by ability to understand and respond in English. The questionnaire consisted of four open-ended questions and 16 closed questions on topics such as material selection for restoring posterior teeth, preclinical teaching of resin composite for posterior teeth, restoration size, contraindications, matrix placement methods, lining use, adhesive selection and finishing. Forty-six schools responded. The outcomes showed all schools included the teaching of resin composite for posterior restorations but varied. The majority of schools (63%) no longer taught amalgam as the preferred posterior restorative material. Half of the schools surveyed set numerical clinical requirements for restoration placement. Australian schools had no requirements whilst 92% of Asian schools did. There was a consensus that larger restorations were less suitable for resin composite. Selection of adhesives depended on region. Generally, the schools surveyed showed minor variations philosophically in teaching of the use and placement of resin composite restorations.

  14. CCL3 and CXCL12 production in vitro by dental pulp fibroblasts from permanent and deciduous teeth stimulated by Porphyromonas gingivalis LPS

    PubMed Central

    SIPERT, Carla Renata; MORANDINI, Ana Carolina de Faria; MODENA, Karin Cristina da Silva; DIONÍSIO, Thiago José; MACHADO, Maria Aparecida Andrade Moreira; de OLIVEIRA, Sandra Helena Penha; CAMPANELLI, Ana Paula; SANTOS, Carlos Ferreira

    2013-01-01

    Objective: The aim of this study was to compare the production of the chemokines CCL3 and CXCL12 by cultured dental pulp fibroblasts from permanent (PDPF) and deciduous (DDPF) teeth under stimulation by Porphyromonas gingivalis LPS (PgLPS). Material and Methods: Primary culture of fibroblasts from permanent (n=3) and deciduous (n=2) teeth were established using an explant technique. After the fourth passage, fibroblasts were stimulated by increasing concentrations of PgLPS (0 - 10 µg/mL) at 1, 6 and 24 h. The cells were tested for viability through MTT assay, and production of the chemokines CCL3 and CXCL12 was determined through ELISA. Comparisons among samples were performed using One-way ANOVA for MTT assay and Two-way ANOVA for ELISA results. Results: Cell viability was not affected by the antigen after 24 h of stimulation. PgLPS induced the production of CCL3 by dental pulp fibroblasts at similar levels for both permanent and deciduous pulp fibroblasts. Production of CXCL12, however, was significantly higher for PDPF than DDPF at 1 and 6 h. PgLPS, in turn, downregulated the production of CXCL12 by PDPF but not by DDPF. Conclusion: These data suggest that dental pulp fibroblasts from permanent and deciduous teeth may present a differential behavior under PgLPS stimulation. PMID:23739851

  15. Teeth number anomalies in permanent dentition among non-syndromic dental patients.

    PubMed

    Aslan, Belma Işik; Akarslan, Zühre Zafersoy

    2013-03-01

    The aim of this study was to establish teeth number anomalies in relation to gender, tooth type, location, distribution pattern and the association between frequently missing teeth among a group of dental patients in Turkey. A total of 378 non-syndromic patients (240 females and 138 males) with an age range of 7-45 (x +/- SD = 22.07 +/- 3.6) having evidence of absent or excess teeth were evaluated in the study. Pearson Chi-square, Fisher's exact, McNemar and Kappa coefficients were used for statistical analysis. 237 patients had a total of 546 congenitally missing teeth and 141 had 185 excess teeth. Congenitally missing teeth were more commonly seen rather than the presence of supernumerary teeth. Difference was determined in the frequent locations of congenital missing and supernumerary teeth. The most frequent missing tooth type was found to be the mandibular second premolar (26.6%), while the majority of supernumerary teeth were located in the anterior region of the maxillary arch (37.9%). Both teeth number anomalies were more commonly seen among females. In hypodontia cases the occurrence of symmetrical agenesis of laterals and second premolars in maxilla; centrals and second premolars in mandible was notable. Agenesis of mandibular centrals was found to be associated with maxillary lateral agenesis in males. Also higher prevalence of molar teeth agenesis was determined in the occurrence of at least 4 teeth agenesis. These findings will serve as information about the contemporary demographic pattern of teeth number anomalies among non-syndromic Turkish dental patients and can provide evidence that agenesis of some teeth symmetrically or together are the products of the same genetic mechanisms. PMID:23697259

  16. Measurement for natural dental neck data of normal adults and its clinical significance on guiding implant restoration

    PubMed Central

    Sun, Mingxu; Gu, Fang; Wang, Junjun; Zhou, Chengyuan; Xia, Junnan; Qin, Hongwei; Yang, Jianjun

    2015-01-01

    Objective: Provide reference basis for the clinical implant restoration to select implant diameter through measuring each data of 7 teeth in the dental neck of bilateral upper and lower jaws of the young volunteers with normal dentition. Methods: Select 30 healthy young volunteers with complete dentition but no malocclusion, take cone beam CT (CBCT), measure the mesiodistal and buccolingual distance of the tooth root at 1.5 mm from 14 teeth (bilateral upper and lower jaws) to alveolar crest, trace out the outline of each tooth neck in this layer, calculate the cross sectional area and roundness of each tooth neck according to pixel value calibration, and then carry out statistical processing. Results: Complete the data collection and processing of mesiodistal length, buccolingual width, cross sectional area, and cross sectional roundness of the dental neck at 1.5 mm from these seven teeth of the bilateral upper and lower jaws to the alveolar crest of 30 volunteers, and calculate the mean value, variance, and reference value range of medical science of each index. Conclusion: CBCT can effectively obtain the image information of the dental neck. Through mimics 10.0 and Photoshop CS3, it is possible to accurately calculate the dental neck length and width, and cross sectional area of each tooth according to CBCT image information. This result can provide reference basis for the implant restoration of the clinical teeth. PMID:26628955

  17. Effects of mercury release from amalgam dental restorations during cremation on soil mercury levels of three New Zealand crematoria

    SciTech Connect

    Nieschmidt, A.K.; Kim, N.D.

    1997-05-01

    A vast amount of research has been undertaken in the last 15-20 years on the corrosion reactions occurring in dental amalgam, release of mercury from amalgam restorations, and the toxic effects of this released mercury on the human body. However, one environmental aspect of amalgam dental restorations that has not received a great deal of attention is the release of mercury during cremation. Mercury is liberated during cremation both because dental amalgams are unstable at cremation temperatures (650-700{degrees}C) and because the free mercury metal is highly volatile. In New Zealand, 58% of deaths are followed by cremation and this figure is likely to rise in the future. This increasing use of cremation as the method of corpse disposal, coupled with the fact that each amalgam restoration is approximately 50% mercury, implies that a significant amount of mercury may be emitted into the environment every year. This study examines mercury released from crematoria in New Zealand. 20 refs., 2 figs., 5 tabs.

  18. Mechanistic aspects of fracture and fatigue in resin based dental restorative composites

    NASA Astrophysics Data System (ADS)

    Shah, Minalben B.

    For resin based dental restorative composites, one of the major challenges is to optimize the balance between mechanical and optical properties. Although fracture is the second leading cause of dental restorative failures, very limited mechanistic understanding exists on a microscopic level. In the present study, the fracture properties and mechanisms of two commercial dental resin composites with different microstructures are examined using double notched four point beam bending and pre-cracked compact-tension, C(T), specimens. Four point bend flexural strength was also measured using un-notched beam samples. The first material is a microhybrid composite that combines a range of nano and micro scale filler particles to give an average particle size of 0.6 mum, while the second is a nanofill composite reinforced entirely with nano particles and their agglomerates. The influences of 60 days water hydration and a post-cure heat treatment were also examined. Fracture resistance curve (R-curve) experiments have demonstrated the microhybrid composite to be more fracture resistant than the nanofill composite in both as-processed and hydrated conditions. Rising fracture resistance with crack extension was observed in all specimens, independent of the environmental conditions. Compared to the as-processed condition, a significant reduction in the peak toughness was observed for the nanofill composite after 60 days of water aging. Hydration lowered flexural strength of both composites which was attributed to hydrolytic matrix degradation with additional interfacial debonding causing larger strength decrease in the nanofill. Optical and SEM observations revealed an interparticle matrix crack path promoting crack deflection as a toughening mechanism in all cases except the hydrated nanofill which showed particle-matrix debonding. Crack bridging was another observed extrinsic toughening mechanism that was believed to be responsible for the rising fracture resistance curve (R

  19. Clinical Evaluation of Reasons for Replacement of Amalgam Restorations in Patients Referring to a Dental School in Iran

    PubMed Central

    Pouralibaba, Firoz; Joulaei, Mohammad; Kashefimehr, Atabak; Pakdel, Farzaneh; Jamali, Zahra; Esmaeili, Ali

    2010-01-01

    Background and aims The present study evaluated the most common reasons for replacing amalgam restorations in a university clinic. Materials and methods A total of 217 restorations which needed to be replaced were clinically and radiographically evaluated in a period of 4 months. The frequencies of reasons for replacing amalgam restorations were calculated: The assessed items included recurrent caries, tooth structure fracture (functional or non-functional cusps), amalgam bulk fracture, amalgam marginal fracture, proximal overhangs, and esthetics. Data were analyzed using Fischer’s exact test. Results Both in vital teeth and teeth which had undergone root canal therapy, the most common reason for amalgam replacement was cusp fracture, with the fracture of non-functional cusps being statistically significant. Recurrent caries was the second most common reason for amalgam replacement. In Class I restorations, the most common reasons were recurrent caries and esthetics, with no statistical significance. The most frequent problem in Class II restorations was fracture of non-functional cusps, with a statistical significance in three-surface restorations. Conclusion According to the results, failing to reduce undermined cusps and neglectful caries removal are the reasons for majority of amalgam restoration replacements. These issues should be emphasized in the curriculum for dental students and continuing education courses. PMID:22991598

  20. Catechol-Functionalized Synthetic Polymer as a Dental Adhesive to Contaminated Dentin Surface for a Composite Restoration.

    PubMed

    Lee, Sang-Bae; González-Cabezas, Carlos; Kim, Kwang-Mahn; Kim, Kyoung-Nam; Kuroda, Kenichi

    2015-08-10

    This study reports a synthetic polymer functionalized with catechol groups as dental adhesives. We hypothesize that a catechol-functionalized polymer functions as a dental adhesive for wet dentin surfaces, potentially eliminating the complications associated with saliva contamination. We prepared a random copolymer containing catechol and methoxyethyl groups in the side chains. The mechanical and adhesive properties of the polymer to dentin surface in the presence of water and salivary components were determined. It was found that the new polymer combined with an Fe(3+) additive improved bond strength of a commercial dental adhesive to artificial saliva contaminated dentin surface as compared to a control sample without the polymer. Histological analysis of the bonding structures showed no leakage pattern, probably due to the formation of Fe-catechol complexes, which reinforce the bonding structures. Cytotoxicity test showed that the polymers did not inhibit human gingival fibroblast cells proliferation. Results from this study suggest a potential to reduce failure of dental restorations due to saliva contamination using catechol-functionalized polymers as dental adhesives.

  1. A novel method of removing artifacts because of metallic dental restorations in 3-D CT images of jaw bone.

    PubMed

    Sohmura, Taiji; Hojoh, Hirokazu; Kusumoto, Naoki; Nishida, Masahiko; Wakabayashi, Kazumichi; Takahashi, Junzo

    2005-12-01

    CT images, especially in a three-dimensional (3-D) mode, give valuable information for oral implant surgery. However, image quality is often severely compromised by artifacts originating from metallic dental restorations, and an effective solution for artifacts is being sought. This study attempts to substitute the damaged areas of the jaw bone images with dental cast model images obtained by CT. The position of the dental cast images was registered to that of the jaw bone images using a devised interface that is composed of an occlusal bite made of self-curing acrylic resin and a marker plate made of gypsum. The patient adapted this interface, and CT images of the stomatognathic system were filmed. On the other hand, this interface was placed between the upper and lower cast models and filmed by CT together with the cast models. The position of the marker plate imaged with the dental casts was registered to those adapted by the patient. The error of registration was examined to be 0.25 mm, which was satisfactory for clinical application. The damaged region in the cranial bone images as an obstacle for implant surgery was removed and substituted with the trimmed images of the dental cast. In the method developed here, the images around the metallic compounds severely damaged by artifacts were successfully reconstructed, and the stomatognathic system images became clear, and this is useful for implant surgery.

  2. Catechol-Functionalized Synthetic Polymer as a Dental Adhesive to Contaminated Dentin Surface for a Composite Restoration

    PubMed Central

    2015-01-01

    This study reports a synthetic polymer functionalized with catechol groups as dental adhesives. We hypothesize that a catechol-functionalized polymer functions as a dental adhesive for wet dentin surfaces, potentially eliminating the complications associated with saliva contamination. We prepared a random copolymer containing catechol and methoxyethyl groups in the side chains. The mechanical and adhesive properties of the polymer to dentin surface in the presence of water and salivary components were determined. It was found that the new polymer combined with an Fe3+ additive improved bond strength of a commercial dental adhesive to artificial saliva contaminated dentin surface as compared to a control sample without the polymer. Histological analysis of the bonding structures showed no leakage pattern, probably due to the formation of Fe–catechol complexes, which reinforce the bonding structures. Cytotoxicity test showed that the polymers did not inhibit human gingival fibroblast cells proliferation. Results from this study suggest a potential to reduce failure of dental restorations due to saliva contamination using catechol-functionalized polymers as dental adhesives. PMID:26176305

  3. Curriculum time compared to clinical procedures in amalgam and composite posterior restorations in U.S. dental schools: a preliminary study.

    PubMed

    Rey, Rosalia; Nimmo, Susan; Childs, Gail S; Behar-Horenstein, Linda S

    2015-03-01

    Dental clinicians have an expanding range of biomaterial choices for restoring tooth structure. Scientific developments in cariology, advances in dental biomaterials, and patients' esthetic concerns have led to a reduction in amalgam restorations and an increase in composite restorations. The aim of this study was to compare teaching time with students' clinical procedures in amalgam and composite posterior restorations in dental schools across the United States. Academic deans in 60 schools were invited to complete a survey that asked for the amount of instructional time for amalgam and composite posterior restorations and the number of clinical restorations performed by their Classes of 2009, 2010, and 2011. Of these 60, 12 returned surveys with complete data, for a 20% response rate. Responses from these schools showed little change in lecture and preclinical laboratory instruction from 2009 to 2011. There was a slight increase in two-surface restorations for both amalgam and composites; however, the total number of reported composite and amalgam restorations remained the same. Of 204,864 restorations reported, 53% were composite, and 47% were amalgam. There were twice as many multisurface large or complex amalgam restorations as composites. One-surface composite restorations exceeded amalgams. Among the participating schools, there was little to no change between curriculum time and clinical procedures. Findings from this preliminary study reflect a modest increase in two-surface resin-based restorations placed by dental students from 2009 to 2011 and little change in curricular time devoted to teaching amalgam restorations. The total number of posterior composite restorations placed by students in these schools was slightly higher than amalgams.

  4. Curriculum time compared to clinical procedures in amalgam and composite posterior restorations in U.S. dental schools: a preliminary study.

    PubMed

    Rey, Rosalia; Nimmo, Susan; Childs, Gail S; Behar-Horenstein, Linda S

    2015-03-01

    Dental clinicians have an expanding range of biomaterial choices for restoring tooth structure. Scientific developments in cariology, advances in dental biomaterials, and patients' esthetic concerns have led to a reduction in amalgam restorations and an increase in composite restorations. The aim of this study was to compare teaching time with students' clinical procedures in amalgam and composite posterior restorations in dental schools across the United States. Academic deans in 60 schools were invited to complete a survey that asked for the amount of instructional time for amalgam and composite posterior restorations and the number of clinical restorations performed by their Classes of 2009, 2010, and 2011. Of these 60, 12 returned surveys with complete data, for a 20% response rate. Responses from these schools showed little change in lecture and preclinical laboratory instruction from 2009 to 2011. There was a slight increase in two-surface restorations for both amalgam and composites; however, the total number of reported composite and amalgam restorations remained the same. Of 204,864 restorations reported, 53% were composite, and 47% were amalgam. There were twice as many multisurface large or complex amalgam restorations as composites. One-surface composite restorations exceeded amalgams. Among the participating schools, there was little to no change between curriculum time and clinical procedures. Findings from this preliminary study reflect a modest increase in two-surface resin-based restorations placed by dental students from 2009 to 2011 and little change in curricular time devoted to teaching amalgam restorations. The total number of posterior composite restorations placed by students in these schools was slightly higher than amalgams. PMID:25729027

  5. Digital data acquisition for a CAD/CAM-fabricated titanium framework and zirconium oxide restorations for an implant-supported fixed complete dental prosthesis.

    PubMed

    Lin, Wei-Shao; Metz, Michael J; Pollini, Adrien; Ntounis, Athanasios; Morton, Dean

    2014-12-01

    This dental technique report describes a digital workflow with digital data acquisition at the implant level, computer-aided design and computer-aided manufacturing fabricated, tissue-colored, anodized titanium framework, individually luted zirconium oxide restorations, and autopolymerizing injection-molded acrylic resin to fabricate an implant-supported, metal-ceramic-resin fixed complete dental prosthesis in an edentulous mandible. The 1-step computer-aided design and computer-aided manufacturing fabrication of titanium framework and zirconium oxide restorations can provide a cost-effective alternative to the conventional metal-resin fixed complete dental prosthesis.

  6. Digital data acquisition for a CAD/CAM-fabricated titanium framework and zirconium oxide restorations for an implant-supported fixed complete dental prosthesis.

    PubMed

    Lin, Wei-Shao; Metz, Michael J; Pollini, Adrien; Ntounis, Athanasios; Morton, Dean

    2014-12-01

    This dental technique report describes a digital workflow with digital data acquisition at the implant level, computer-aided design and computer-aided manufacturing fabricated, tissue-colored, anodized titanium framework, individually luted zirconium oxide restorations, and autopolymerizing injection-molded acrylic resin to fabricate an implant-supported, metal-ceramic-resin fixed complete dental prosthesis in an edentulous mandible. The 1-step computer-aided design and computer-aided manufacturing fabrication of titanium framework and zirconium oxide restorations can provide a cost-effective alternative to the conventional metal-resin fixed complete dental prosthesis. PMID:25258258

  7. Finite element modeling of dental restoration through multi-material laser densification

    NASA Astrophysics Data System (ADS)

    Dai, Kun

    To provide guidance for intelligent selection of various parameters in the Multi-Material Laser Densification (MMLD) process for dental restorations, finite element modeling (FEM) has been carried out to investigate the MMLD process. These modeling investigations include the thermal analysis of the nominal surface temperature that should be adopted during experiments in order to achieve the desired microstructure; the effects of the volume shrinkage due to transformation from a powder compact to dense liquid on the temperature distribution and the size of the transformation zone; the evolution of transient temperature, transient stresses, residual stresses and distortions; and the effects of laser processing conditions, such as fabrication sequences, laser scanning patterns, component sizes, preheating temperatures, laser scanning rates, initial porosities, and thicknesses of each powder layer, on the final quality of the component fabricated via the MMLD process. The simulation results are compared with the experiments. It is found that the predicted temperature distribution matches the experiments very well. The nominal surface temperature applied on the dental porcelain body should be below 1273 K to prevent the forming of the un-desired microstructure (i.e., a leucite-free glassy phase). The simplified models that do not include the volume shrinkage effect provide good estimations of the temperature field and the size of the laser-densified body, although the shape of the laser-densified body predicted is different from that obtained in the experiment. It is also fount that warping and residual thermal stresses of the laser-densified component are more sensitive to the chamber preheating temperature and the thickness of each powder layer than to the laser scanning rate and the initial porosity of the powder layer. The major mechanism responsible for these phenomena is identified to be related to the change of the temperature gradient induced by these laser

  8. Assessing ex vivo dental biofilms and in vivo composite restorations using cross-polarization optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Jones, R.; Aparicio, C.; Chityala, R.; Chen, R.; Fok, A.; Rudney, J.

    2012-01-01

    A cross-polarization 1310-nm optical coherence tomography system (CP-OCT), using a beam splitter based design, was used to assess ex vivo growth of complex multi-species dental biofilms. These biofilm microcosms were derived from plaque samples along the interface of composite or amalgam restoration in children with a history of early childhood caries. This paper presents a method of measuring the mean biofilm height of mature biofilms using CP-OCT. For our in vivo application, the novel swept source based CP-OCT intraoral probe (Santec Co. Komaki, Japan) dimensions and system image acquisition speed (20 image frames/second) allowed imaging pediatric subjects as young as 4 years old. The subsurface enamel under the interface of composite resin restorations of pediatric subjects were imaged using CP-OCT. Cavitated secondary caries is clearly evident from sound resin composite restorations.

  9. Optical coherence tomography based imaging of dental demineralisation and cavity restoration in 840 nm and 1310 nm wavelength regions

    NASA Astrophysics Data System (ADS)

    Damodaran, Vani; Rao, Suresh Ranga; Vasa, Nilesh J.

    2016-08-01

    In this paper, a study of in-house built optical coherence tomography (OCT) system with a wavelength of 840 nm for imaging of dental caries, progress in demineralisation and cavity restoration is presented. The caries when imaged with the 840 nm OCT system showed minute demineralisation in the order of 5 μm. The OCT system was also proposed to study the growth of lesion and this was demonstrated by artificially inducing caries with a demineralisation solution of pH 4.8. The progress of carious lesion to a depth of about 50-60 μm after 60 hours of demineralisation was clearly observed with the 840 nm OCT system. The tooth samples were subjected to accelerated demineralisation condition at pH of approximately 2.3 to study the adverse effects and the onset of cavity formation was clearly observed. The restoration of cavity was also studied by employing different restorative materials (filled and unfilled). In the case of restoration without filler material (unfilled), the restoration boundaries were clearly observed. Overall, results were comparable with that of the widely used 1310 nm OCT system. In the case of restoration with filler material, the 1310 nm OCT imaging displayed better imaging capacity due to lower scattering than 840 nm imaging.

  10. Frequency and variability of dental morphology in deciduous and permanent dentition of a Nasa indigenous group in the municipality of Morales, Cauca, Colombia

    PubMed Central

    Díaz, Eider; García, Lorena; Hernández, Michelle; Palacio, Lesly; Ruiz, Diana; Velandia, Nataly; Villavicencio, Judy

    2014-01-01

    Objectives: To determine the frequency, variability, sexual dimorphism and bilateral symmetry of fourteen dental crown traits in the deciduous and permanent dentition of 60 dental models (35 women and 25 men) obtained from a native, indigenous group of Nasa school children of the Musse Ukue group in the municipality of Morales, Department of Cauca, Colombia. Methods: This is a quantitative, descriptive, cross-sectional study that characterizes dental morphology by means of the systems for temporary dentition from Dahlberg (winging), and ASUDAS (crowding, reduction of hypocone, metaconule and cusp 6), Hanihara (central and lateral incisors in shovel-shape and cusp 7), Sciulli (double bit, layered fold protostylid, cusp pattern and cusp number) and Grine (Carabelli trait); and in permanent dentition from ASUDAS (Winging, crowding, central and lateral incisors in shovel-shape and double shovel-shape, Carabelli trait, hypocone reduction, metaconule, cusp pattern, cusp number, layered fold protostylid, cusp 6 and cusp 7). Results: The most frequent dental crown features were the shovel-shaped form, grooved and fossa forms of the Carabelli trait, metaconule, cusp pattern Y6, layered fold, protostylid (point P) and cusp 6. Sexual dimorphism was not observed and there was bilateral symmetry in the expression of these features. Conclusions: The sample studied presented a great affinity with ethnic groups belonging to the Mongoloid Dental Complex due to the frequency (expression) and variability (gradation) of the tooth crown traits, upper incisors, the Carabelli trait, the protostylid, cusp 6 and cusp 7. The influence of the Caucasoide Dental Complex associated with ethno-historical processes cannot be ruled out. PMID:24970955

  11. Biphenyl liquid crystalline epoxy resin as a low-shrinkage resin-based dental restorative nanocomposite.

    PubMed

    Hsu, Sheng-Hao; Chen, Rung-Shu; Chang, Yuan-Ling; Chen, Min-Huey; Cheng, Kuo-Chung; Su, Wei-Fang

    2012-11-01

    Low-shrinkage resin-based photocurable liquid crystalline epoxy nanocomposite has been investigated with regard to its application as a dental restoration material. The nanocomposite consists of an organic matrix and an inorganic reinforcing filler. The organic matrix is made of liquid crystalline biphenyl epoxy resin (BP), an epoxy resin consisting of cyclohexylmethyl-3,4-epoxycyclohexanecarboxylate (ECH), the photoinitiator 4-octylphenyl phenyliodonium hexafluoroantimonate and the photosensitizer champhorquinone. The inorganic filler is silica nanoparticles (∼70-100 nm). The nanoparticles were modified by an epoxy silane of γ-glycidoxypropyltrimethoxysilane to be compatible with the organic matrix and to chemically bond with the organic matrix after photo curing. By incorporating the BP liquid crystalline (LC) epoxy resin into conventional ECH epoxy resin, the nanocomposite has improved hardness, flexural modulus, water absorption and coefficient of thermal expansion. Although the incorporation of silica filler may dilute the reinforcing effect of crystalline BP, a high silica filler content (∼42 vol.%) was found to increase the physical and chemical properties of the nanocomposite due to the formation of unique microstructures. The microstructure of nanoparticle embedded layers was observed in the nanocomposite using scanning and transmission electron microscopy. This unique microstructure indicates that the crystalline BP and nanoparticles support each other and result in outstanding mechanical properties. The crystalline BP in the LC epoxy resin-based nanocomposite was partially melted during exothermic photopolymerization, and the resin expanded via an order-to-disorder transition. Thus, the post-gelation shrinkage of the LC epoxy resin-based nanocomposite is greatly reduced, ∼50.6% less than in commercialized methacrylate resin-based composites. This LC epoxy nanocomposite demonstrates good physical and chemical properties and good biocompatibility

  12. Prevalence of dental caries in primary and permanent teeth and its relation with tooth brushing habits among schoolchildren in Eastern Saudi Arabia

    PubMed Central

    Farooqi, Faraz A.; Khabeer, Abdul; Moheet, Imran A.; Khan, Soban Q.; Farooq, Imran; ArRejaie, Aws S.,

    2015-01-01

    Objectives: To determine the prevalence of dental caries in the primary and permanent teeth, and evaluate the brushing habits of school children in Dammam, Kingdom of Saudi Arabia (KSA). Methods: This study was conducted at Dammam, KSA. Oral examination of the participants was conducted from February to May 2014. The total sample size for this cross-sectional study was 711. There were 397 children between the age of 6-9 years, who were examined for primary teeth caries, and 314 between the age 10-12 years were examined for permanent teeth caries. Primary and permanent dentitions were studied for decayed, missing, and filled teeth (dmft [primary teeth], DMFT [permanent teeth]). Results: The overall prevalence of dental caries in primary and permanent teeth was almost 73% (n=711). Among the 6-9-year-old, the prevalence of caries was approximately 78% (n=397) whereas, among the 10-12-year-old children, it was approximately 68% (n=314). Mean dmft value among the 6-9-year-olds was 3.66±3.13 with decayed (d) component of 3.28±2.92, missing (m) component of 0.11±0.69, and filled (f) component of 0.26±0.9. Mean DMFT value among the 10-12-year-old children was 1.94±2.0 with decayed (D) component of 1.76±1.85, missing (M) component of 0.03±0.22, and filled (F) of component 0.15±0.73. Daily tooth brushing had a positive effect on caries prevention, and this effect was statistically significant for caries in primary teeth. Conclusion: Although the prevalence of dental caries in primary and permanent teeth was not found to be as high as other researchers reported from different cities of KSA, still the prevalence was high considering the World Health Organization future oral health goals. Awareness should be provided to students, as well as, teachers and parents regarding the importance of good brushing habits and regular dental visits. PMID:25987118

  13. Posterior restorations--a clinical view.

    PubMed

    Jedynakiewicz, N M; Martin, N

    2001-01-01

    This paper examines the state-of-the-art in the direct restoration of posterior teeth. The existing paradigms for the management of caries are questioned and some existing methods of cavity preparation are reviewed. Dental restorations need to be durable but able to adapt to a changing environment brought about by wear of the adjacent tooth substance and by fatigue processes within the tooth itself. The wear of restorative materials needs to be matched to that of the tooth, otherwise differential loss of either the restorative material or the enamel may destabilize the occlusion. Esthetic instability due to natural darkening of the tooth with age, punctuated by clinical intervention with bleaching procedures, adds a further dimension to the concept of a permanent restoration. Clinical methods that minimize the disruptive effects of dental restorations upon the remaining tooth structure are a continuing challenge.

  14. N-Acetyl cysteine restores viability and function of rat odontoblast-like cells impaired by polymethylmethacrylate dental resin extract.

    PubMed

    Yamada, Masahiro; Kojima, Norinaga; Att, Wael; Hori, Norio; Suzuki, Takeo; Ogawa, Takahiro

    2009-01-01

    There is concern that dental-resin materials directly loaded on a prepared tooth adversely affect dental pulp tissue by releasing the resin chemicals through dentinal tubes. This study determined whether self-curing polymethyl methacrylate (PMMA)-based dental resin extract adversely affected the viability and function of odontoblast-like cells and whether the cytotoxicity of this resin, if any, could be eliminated by N-acetyl cysteine, an antioxidant amino acid derivative. Odontoblast-like cells isolated from rat maxillary incisor dental pulp tissue were exposed to a PMMA resin extract with or without N-acetyl cysteine for 1 h and then cultured in osteoblastic media. The percentage of viable cells 24 h after seeding was 20% in cells exposed to the resin extract without N-acetyl cysteine, whereas 45% of cells were viable after exposure to the N-acetyl cysteine-supplemented extract. The cells that had been exposed to the extract showed a strong tendency for apoptosis associated with the increased reactive oxygen species production and decreased intracellular glutathione level, which was improved by the addition of N-acetyl cysteine. N-Acetyl cysteine supplementation almost completely restored the significantly reduced alkaline phosphatase activity and matrix mineralization by the resin extract. These results conclusively demonstrated that exposure of odontoblast-like cells to the resin extract impaired the cell viability and function and, more intriguingly, N-acetyl cysteine supplementation to the extract significantly prevented these toxic effects.

  15. Optical properties of dental restorative materials in the wavelength range 400 to 700 nm for the simulation of color perception.

    PubMed

    Friebel, Moritz; Povel, Kirsten; Cappius, Hans-Joachim; Helfmann, Jürgen; Meinke, Martina

    2009-01-01

    Aesthetic restorations require dental restorative materials to have optical properties very similar to those of the teeth. A method is developed to this end to determine the optical parameters absorption coefficient mu(a), scattering coefficient mu(s), anisotropy factor g, and effective scattering coefficient mu(s) (') of dental restorative materials. The method includes sample preparation and measurements of transmittance and reflectance in an integrating sphere spectrometer followed by inverse Monte Carlo simulations. Using this method the intrinsic optical parameters are determined for shade B2 of the light-activated composites TPH((R)) Spectrum, Esthet-X, and the Ormocer Definite in the wavelength range 400 to 700 nm. By using the determined parameters mu(a), mu(s), and g together with an appropriate phase function, the reflectance of samples with 1-mm layer thickness and shade B2 could be predicted with a very high degree of accuracy using a forward Monte Carlo simulation. The color perception was calculated from the simulated reflectance according to the CIELAB system. We initiate the compilation of a data pool of optical parameters that in the future will enable calculation models to be used as a basis for optimization of the optical approximation of the natural tooth, and the composition of new materials and their production process.

  16. Optical properties of dental restorative materials in the wavelength range 400 to 700 nm for the simulation of color perception

    NASA Astrophysics Data System (ADS)

    Friebel, Moritz; Povel, Kirsten; Cappius, Hans-Joachim; Helfmann, Jürgen; Meinke, Martina

    2009-09-01

    Aesthetic restorations require dental restorative materials to have optical properties very similar to those of the teeth. A method is developed to this end to determine the optical parameters absorption coefficient μa, scattering coefficient μs, anisotropy factor g, and effective scattering coefficient μs' of dental restorative materials. The method includes sample preparation and measurements of transmittance and reflectance in an integrating sphere spectrometer followed by inverse Monte Carlo simulations. Using this method the intrinsic optical parameters are determined for shade B2 of the light-activated composites TPH® Spectrum®, Esthet-X®, and the Ormocer® Definite® in the wavelength range 400 to 700 nm. By using the determined parameters μa, μs, and g together with an appropriate phase function, the reflectance of samples with 1-mm layer thickness and shade B2 could be predicted with a very high degree of accuracy using a forward Monte Carlo simulation. The color perception was calculated from the simulated reflectance according to the CIELAB system. We initiate the compilation of a data pool of optical parameters that in the future will enable calculation models to be used as a basis for optimization of the optical approximation of the natural tooth, and the composition of new materials and their production process.

  17. The Efficacy of Noncontingent Escape for Decreasing Children's Disruptive Behavior during Restorative Dental Treatment

    ERIC Educational Resources Information Center

    O'Callaghan, Patrick M.; Allen, Keith D.; Powell, Shawn; Salama, Fouad

    2006-01-01

    We evaluated the effectiveness of a dentist-implemented behavioral intervention in which brief escape from dental treatment was provided on a regular basis, independent of the child's behavior. Within a multiple baseline design across subjects, 5 children, ages 4 to 7 years, were provided with temporary escape from dental treatment on a fixed-time…

  18. Dental restoration with endosseous implants after mandibular reconstruction using a fibula free flap and TMJ prosthesis: a patient report.

    PubMed

    Infante-Cossio, Pedro; Torres-Lagares, Daniel; Martinez-de-Fuentes, Rafael; Garcia-Perla-Garcia, Alberto; Gutierrez-Perez, Jose-Luis

    2006-01-01

    This patient report describes the secondary reconstruction of a hemimandibular and condylar defect and the dental restoration of a 56-year-old woman who had been subjected to radical ablative surgery 30 years earlier to remove a tumor. In the first phase, a fibula free flap was used in combination with a total TMJ prosthesis for the reconstruction of the hemimandible and condyle. Secondly, 3 endosseous implants were placed in the residual mandible. These implants were used to support an overdenture prosthesis that has remained in continuous function for a period of 2 years.

  19. Clinical Investigation of a New Bulk Fill Composite Resin in the Restoration of Posterior Teeth

    ClinicalTrials.gov

    2016-09-07

    Dental Restoration Failure of Marginal Integrity; Dental Caries; Unrepairable Overhanging of Dental Restorative Materials; Poor Aesthetics of Existing Restoration; Secondary Dental Caries Associated With Failed or Defective Dental Restorations; Fractured Dental Restorative Materials Without Loss of Materials; Fracture of Dental Restorative Materials With Loss of Material

  20. Fluoride Release and Uptake of Five Dental Restoratives from Mouthwashes and Dentifrices

    PubMed Central

    Rao, B Saketh Rama; Moosani, Gopi Krishna Reddy; Shanmugaraj, Muthu; Kannapan, Balamurugan; Shankar, B. Shiva; Ismail, Prabu Mahin Syed

    2015-01-01

    Background: This study evaluated the fluoride release and uptake of five common dental restoratives mainly glass ionomer formulations, including a conventional glass ionomer, a relatively new caries stabilization glass ionomer and resin-modified glass ionomer (Fuji II, Fuji VII and Fuji II LC); one compomer (F2000); and one fluoride releasing composite resin (tetric ceram). Materials and Methods: A total of 12 cylindrical specimens for each of the five materials were prepared following manufacturer’s instructions for manipulation and immersed independently in 25 ml of artificial saliva and stored as five groups Group I-V. Each group was further divided into three sub Groups A, B, C. The saliva was changed every day in all the specimens. No treatment was carried out for the specimens in subgroup A. The specimens were immersed in 2% sodium fluoride for 1 min before changing saliva in sub group B and the specimens were treated by brushing with a fluoridated dentifrice for 2 min before changing saliva in sub Group C. The fluoride release was evaluated on the 1st, 7th and 28th day using a fluoride ion specific electrode. Results: The results demonstrated that the conventional glass ionomer and the recently introduced caries stabilizing glass ionomer showed similar patterns and quantity of fluoride release, which was significantly higher than the resin-modified glass ionomer, the compomer and the composite resin. The resin-modified glass ionomer showed higher fluoride release than the compomer and the composite resin. All the formulations of glass ionomers showed fluoride uptake from the neutral sodium fluoride and the fluoridated dentifrice, by releasing increased amounts of fluoride after treatment, in comparison with the untreated group. However, the compomer and the composite resin showed no fluoride uptake. Conclusion: The fluoride released by the glass ionomer cements (GICs) was found to be highest during the first 24 h and decreased significantly over the 1st

  1. Multiple Unerupted Permanent Teeth Associated with Noonan Syndrome

    PubMed Central

    Uloopi, KS; Madhuri, V; Gopal, AS; Vinay, C; Chandrasekhar, R

    2015-01-01

    The present report describes a case of Noonan's syndrome from a dental viewpoint. Noonan syndrome is an autosomal dominant multisystem disorder. Congenital heart deformities, short stature, thoracic deformities, short neck with webbing, hypertelorism, and malocclusions are some of the frequently observed clinical features. Atypical dental anomalies such as multiple unerupted permanent teeth, multiple submerged and retained deciduous teeth, and supernumerary teeth were found in the present case. Oral prophylaxis and preventive resin restorations were done following which the supernumerary teeth were extracted. 54, 55, 64, 65, 74, 75 and 84 were extracted after orthodontic consultation to facilitate the eruption of permanent teeth. The patient is undergoing fixed orthodontic therapy for forced eruption of unerupted permanent teeth. General dentists should correlate dental anomalies with other systemic features in the diagnosis of such syndromes because of the variability in presentation and the need for multidisciplinary care. PMID:26229724

  2. Preparing and Restoring Composite Resin Restorations. The Advantage of High Magnification Loupes or the Dental Surgical Operating Microscope.

    PubMed

    Mamoun, John

    2015-01-01

    Use of magnification, such as 6x to 8x binocular surgical loupes or the surgical operating microscope, combined with co-axial illumination, may facilitate the creation of stable composite resin restorations that are less likely to develop caries, cracks or margin stains over years of service. Microscopes facilitate observation of clinically relevant microscopic visual details, such as microscopic amounts of demineralization or caries at preparation margins; microscopic areas of soft, decayed tooth structure; microscopic amounts of moisture contamination of the preparation during bonding; or microscopic marginal gaps in the composite. Preventing microscope-level errors in composite fabrication can result in a composite restoration that, at initial placement, appears perfect when viewed under 6x to 8x magnification and which also is free of secondary caries, marginal staining or cracks at multi-year follow-up visits.

  3. Preparing and Restoring Composite Resin Restorations. The Advantage of High Magnification Loupes or the Dental Surgical Operating Microscope.

    PubMed

    Mamoun, John

    2015-01-01

    Use of magnification, such as 6x to 8x binocular surgical loupes or the surgical operating microscope, combined with co-axial illumination, may facilitate the creation of stable composite resin restorations that are less likely to develop caries, cracks or margin stains over years of service. Microscopes facilitate observation of clinically relevant microscopic visual details, such as microscopic amounts of demineralization or caries at preparation margins; microscopic areas of soft, decayed tooth structure; microscopic amounts of moisture contamination of the preparation during bonding; or microscopic marginal gaps in the composite. Preventing microscope-level errors in composite fabrication can result in a composite restoration that, at initial placement, appears perfect when viewed under 6x to 8x magnification and which also is free of secondary caries, marginal staining or cracks at multi-year follow-up visits. PMID:26373029

  4. Pulp-dentin biology in restorative dentistry. Part 4: Dental caries--characteristics of lesions and pulpal reactions.

    PubMed

    Bjørndal, L; Mjör, I A

    2001-10-01

    The infectious disease dental caries results in lesions that may affect enamel, dentin, pulp, and cementum. If a caries lesion has progressed to the stage at which it requires restorative intervention, it is important that the clinician understand the tissue changes in the dentin that are likely to have taken place during lesion development. Until the present, no major distinction between the restorative treatment of active (rapidly progressing) and arrested (slowly progressing) lesions has been made, despite the fact that the two conditions exhibit major differences in tissue changes in the pulp-dentin complex. Intratubular changes and tertiary dentin formation will affect the outcome of the restorative treatment. In unaffected dentin and in rapidly progressing lesions, permeable tubules persist, and when the preparation of carious teeth results in the opening of unaffected dentin, greater care must be taken in all phases of the restorative procedures than if the dentin is impermeable. An active, deep lesion can be changed to an arrested lesion by a two-step excavation approach. Optimal assessment of the prevailing clinical conditions can only be made on the basis of thorough knowledge of the biology of the pulp-dentin organ.

  5. Restoration of occlusal vertical dimension in dental erosion caused by gastroesophageal reflux: case report.

    PubMed

    Reston, Eduardo Galia; Closs, Luciane Quadrado; Busato, Adair Luiz Stefanello; Broliato, Gustavo André; Tessarollo, Fábio Rafael

    2010-01-01

    The authors describe a minimally invasive procedure for occlusal rehabilitation in a young patient presenting with mild mandibular prognathism and loss of occlusal vertical dimension caused by dental erosion from chronic gastroesophageal reflux.

  6. A clinical study on the effectiveness of implant supported dental restoration in patients with chronic periodontal diseases.

    PubMed

    Jiang, B Q; Lan, J; Huang, H Y; Liang, J; Ma, X N; Huo, L D; Xu, X

    2013-02-01

    This study evaluated the efficacy of implant supported dental restorations in patients with chronic periodontal diseases at various stages within 2 years of completing treatment. 30 patients with periodontal diseases and 30 patients without periodontal diseases were studied. Total counts of 276 implant bodies were divided into group A (patients with periodontal diseases; a total of 149 implants) and group B (patients with healthy periodontium; a total of 127 implants). In group A subjects, periodontitis was treated prior to implant placement. The study focused on patients' modified sulcus bleeding index, modified plaque index, implant mobility index, periodontal probing depth and implant success rate 12 and 24 months after the completion of the treatment. The result show: there were no significant differences in implant success rate between groups A and B; modified sulcus bleeding index scores showed differences between the groups 24 months after treatment; there were no significant differences in other clinical indexes during the study between the groups; there were no significant differences in periodontal probing depth between the groups; modified plaque index and modified sulcus bleeding index were positively correlated in implant supported dental restoration patients with chronic periodontal diseases.

  7. Non-thermal Atmospheric Plasma Treatment for Deactivation of Oral Bacteria and Improvement of Dental Composite Restoration

    NASA Astrophysics Data System (ADS)

    Yu, Qing Song; Li, H.; Ritts, A. C.; Yang, B.; Chen, M.; Hong, L.; Xu, C.; Yao, X.; Wang, Y.

    This paper reviews our recent research results of using non-thermal ­atmospheric plasmas for oral bacterial deactivation and for composite restoration improvement. Oral bacteria of Streptococcus mutans (S. mutans) and Lactobacillus acidophilus (L. acidophilus) with an initial bacterial population density between 1.0 × 108 and 5.0 × 108 cfu/ml were seeded on various media and their survivability with plasma exposure was examined. The plasma exposure time for a 99.9999% cell reduction was less than 15 s for S. mutans and within 5 min for L. acidophilus. To evaluate the dentin/composite interfacial bonding, extracted unerupted human third molars were used by removing the crowns and etching the exposed dentin surfaces with 35% phosphoric acid gel. After dental composite application and light curing, the teeth were then sectioned into micro-bars as the specimens for microtensile test. Student Newman Keuls (SNK) tests showed that the bonding strength of the composite restoration to peripheral dentin was significantly increased (by 64%) after 30 s plasma treatment of the dentin surfaces. These findings indicated that non-thermal atmospheric plasma technology is very promising for dental clinical applications.

  8. Optimizing the design of bio-inspired functionally graded material (FGM) layer in all-ceramic dental restorations.

    PubMed

    Cui, Chang; Sun, Jian

    2014-01-01

    Due to elastic modulus mismatch between the different layers in all-ceramic dental restorations, high tensile stress concentrates at the interface between the ceramic core and cement. In natural tooth structure, stress concentration is reduced by the functionally graded structure of dentin-enamel junction (DEJ) which interconnects enamel and dentin. Inspired by DEJ, the aim of this study was to explore the optimum design of a bio-inspired functionally graded material (FGM) layer in all-ceramic dental restorations to achieve excellent stress reduction and distribution. Three-dimensional finite element model of a multi-layer structure was developed, which comprised bilayered ceramic, bio-inspired FGM layer, cement, and dentin. Finite element method and first-order optimization technique were used to realize the optimal bio-inspired FGM layer design. The bio-inspired FGM layer significantly reduced stress concentration at the interface between the crown and cement, and stresses were evenly distributed in FGM layer. With the optimal design, an elastic modulus distribution similar to that in DEJ occurred in the FGM layer.

  9. Ensuring the global availability of high-quality dental restorative materials.

    PubMed

    Ferracane, J; Fisher, J; Eiselé, J L; Fox, C H

    2013-11-01

    The Minamata Convention, a global legally binding instrument (treaty) on mercury, has been the catalyst for the emerging agenda on global dental materials research. If the current and future challenges of oral health maintenance and healing on a global scale are to be met, a logical and effective research agenda for the discovery and introduction of new, environmentally sustainable, dental materials must be developed through a coordinated effort involving materials scientists, dental clinicians, representatives of industry, members of regional and national regulatory bodies, and advocacy from research organizations. For universal impact, this agenda should be created with awareness of several important ongoing initiatives, such as the WHO non-communicable diseases action plan, the UN sustainable development agenda, and the IADR Global Oral Health In Inequalities Research Agenda (GOHIRA). A significant contributor to this cause is the FDI and its membership, who, through their Vision 2020 initiative, acknowledge their role and responsibility in globally preventing and managing dental disease and providing leadership to the profession in terms of information dissemination and affecting change. Dental researchers also have an obligation to advocate for appropriate funding to match the identified research needs, thus enhancing the possibility that key decision-makers will provide the needed support to achieve the research agenda agreed upon by this diverse group of stakeholders.

  10. Development of dental restorative materials based on visible light-cured multi-methacrylates

    NASA Astrophysics Data System (ADS)

    Tiba, Amer

    that the BPA oligomer (multi-methacrylate) based resin significantly favored the cell growth of the human gingival fibroblasts, compared to the control. An experimental composite was made from EPBPA oligomers (multi-methacrylates). The compressive strength of the experimental EPBPA containing composite was not significantly different than the commercial composite Herculite HXR. SEM photomicrographs revealed more voids in the experimental composites than the commercial composite on both the external surfaces of the prepared specimens and the subsequent fractured surfaces. This is due to the molding technique for specimen preparation and lack of good mechanical mixing for filler incorporation prior to placement of the resin in the mold for subsequent photopolymerization. However, the water sorption for the experimental EPBPA-based composite was significantly lower than the commercial Herculite (HXR) composite. This is most likely related to the hydrophobic nature of the experimental resin. These results suggest that the new type of polyfunctional methacrylate oligomers (PEBPA) have potential application in formulating dental composites as direct esthetic restorative materials with improved properties.

  11. Recommendations for conducting controlled clinical studies of dental restorative materials. Science Committee Project 2/98--FDI World Dental Federation study design (Part I) and criteria for evaluation (Part II) of direct and indirect restorations including onlays and partial crowns.

    PubMed

    Hickel, Reinhard; Roulet, Jean-François; Bayne, Stephen; Heintze, Siegward D; Mjör, Ivar A; Peters, Mathilde; Rousson, Valentin; Randall, Ros; Schmalz, Gottfried; Tyas, Martin; Vanherle, Guido

    2007-01-01

    clinical trial designs, guidelines for design, randomization, number of subjects, characteristics of participants, clinical assessment, standards and calibration, categories for assessment, criteria for evaluation, and supplemental documentation. Part 2 of the review considers categories of assessment for esthetic evaluation, functional assessment, biological responses to restorative materials, and statistical analysis of results. The overall review represents a considerable effort to include a range of clinical research interests over the past years. As part of the recognition of the importance of these suggestions, the review is being published simultaneously in identical form in both the Journal of Adhesive Dentistry and Clinical Oral Investigations. Additionally, an extended abstract will be published in the International Dental Journal, giving a link to the web full version. This should help to introduce these considerations more quickly to the scientific community.

  12. 3D finite element analysis on esthetic indirect dental restorations under thermal and mechanical loading.

    PubMed

    Cornacchia, Tulimar P M; Las Casas, Estevam B; Cimini, Carlos Alberto; Peixoto, Rodrigo G

    2010-11-01

    Thermo-mechanical finite element analyses in 3-D models are described for determination of the stress levels due to thermal and mechanical loads in a healthy and restored tooth. Transient thermo-mechanical analysis simulating the ingestion of cold and hot drinks was performed to determine the temperature distribution in the models of the teeth, followed by linear elastic stress analyses. The thermal loads were applied on the occlusal and lingual surfaces. Subsequently, coupled variation of the temperature and mastication loading was considered. The vertical loading was distributed at occlusal points, adding up to 180 N. Maximum stresses were verified in resin restoration under thermal loads. When studying coupled effect of mechanical loading with that arising from thermal effects, higher tensile stress values occurred in porcelain restorations, especially at the restoration-dentin interface. Regions of high tensile stress were detected and their possible clinical significance with respect to restoration damage and microleakage were discussed.

  13. Evaluation of microleakage of class II dental composite resin restorations cured with LED or QTH dental curing light; Blind, Cluster Randomized, In vitro cross sectional study

    PubMed Central

    2014-01-01

    Background The aim of this study is to compare the microleakage of Class II dental composite resin restorations which have been cured by three different LED (light emitting diode) light curing modes compared to control samples cured by QTH (quartz tungsten halogen) light curing units (LCUs), to determine the most effective light curing unit and mode of curing. Results In this experimental study, class II cavities were prepared on 100 sound human premolars which have been extracted for orthodontic treatment. The teeth were randomly divided into four groups; three experimental and one control group of 25 teeth each. Experimental groups were cured by either conventional, pulse-delay, or ramped curing modes of LED. The control group was cured for 20 seconds by QTH. The restorations were thermocycled (1000 times, between 5 and 55°C, for 5 seconds dwell time), dyed, sectioned mesio-distally and viewed under stereo-microscope (40×) magnification. Teeth were then scored on a 0 to 4 scale based on the amount of microleakage. The data were analyzed by Chi-square test. No significant difference was demonstrated between the different LCUs (light curing units), or modes of curing, at the enamel side (p > 0.05). At the dentin side, all modes of LED curing could significantly reduce microleakage (p < 0.05). The results suggest that slow start curing improves marginal integrity and seal. High intense curing endangers those aims. Conclusions Comparison between the three LED mode cured composite resin restorations and QTH curing showed LED curing in all modes is more effective than QTH for reducing microleakage. Both LED and QTH almost completely eliminate the microleakage on the enamel side, however none of them absolutely eliminated microleakage on the dentin side. PMID:24990296

  14. Adjunctive role of dental restorations in personal identification of burnt victims

    PubMed Central

    Vandrangi, Sameer Kumar; Radhika, MB; Paremala, K; Reshma, V; Sudhakara, M; Hosthor, Sreelatha S

    2016-01-01

    Background: Fire remains one of the major causes of morbidity and mortality throughout the world and identification of a body from the fatal fire remains a daunting task. Several forensic cases involve interpretation of burnt human bodies from airline and automobile accidents, bombings and unlawful cremation. Fire is also involved in homicides, suicides, accidental death, arson and in attempts to destroy forensic evidence in criminal cases. Soft tissue destruction from fire can be so extensive that conventional methods of identification may be impossible. However, teeth survive even high temperatures due to their resistant composition and so, obviously, the restorative material housed in the teeth are even more secure and can yield valuable information in personal identification. Aim: To assess the usefulness of most common restorations in personal identification in burnt cases. Materials and Methods: The study was conducted on 40 extracted teeth which were divided into four groups (Group 1 - Unrestored teeth, Group 2 - Amalgam restored, Group 3 - Glass ionomer restored and Group 4 - Composite resin restored teeth. The effect of incineration at 200°C, 400°C, 600°C, 800°C, 1000°C for 15 min at each target temperature followed by subsequent cooling was studied. Results: Amalgam restoration was resistant and intact even at 1000°C, whereas GIC and composite restoration are identifiable till 600°C, the residual cavity preparation leaves a clue for narrowing down the spectrum of identification. PMID:27194881

  15. Tongue piercing: a restorative perspective.

    PubMed

    Bassiouny, M A; Deem, L P; Deem, T E

    2001-06-01

    The implication of a traumatic injury to a permanent molar tooth as a complication by tongue piercing with ornamental jewelry is reported. An appropriate restorative management of the fractured tooth is described. The dentist's role in prevention and treatment of unfavorable complications is outlined. The rationales for selection of specific treatment modalities, in view of the degree of damage to hard dental tissues, are discussed. The range of hard tissue injuries resulting from tongue jewelry varies from a simple crack propagating into the enamel to a fractured tooth. A variety of factors must be considered before employing the available restorative methods. PMID:11491628

  16. Three-dimensional inclination of the dental axes in healthy permanent dentitions--A cross-sectional study in a normal population.

    PubMed

    Ferrario, V F; Sforza, C; Colombo, A; Ciusa, V; Serrao, G

    2001-08-01

    The 3-dimensional (3-D) inclination of the facial axis of the clinical crown (FACC) and the size of the clinical crowns were measured in 100 white northern Italians. The subjects consisted of 22 girls and 21 boys, ages 13-15 years (adolescents), and 31 women and 26 men, ages 16-26 years (adults), all with a complete permanent dentition and Class I dental relationships. The 3-D coordinates of dental landmarks were obtained with a computerized electromagnetic digitizer. Clinical crowns heights and FACC inclinations in the anatomical frontal and sagittal planes relative to 2 reference planes, maxillary and mandibular (between the incisive papilla and the intersection of the palatal/lingual sulci of the first permanent molars with the gingival margin), were calculated. Ages and sexes were compared by ANOVA. On average, the frontal plane FACCs of most teeth converged toward the midline plane of symmetry. In contrast, the incisors diverged from the midline plane or were nearly vertical. Within each quadrant, the inclinations of the postincisor teeth progressively increased. In the sagittal plane, most teeth had a nearly vertical FACC. FACC inclinations showed sex- and age-related differences (P < .05). In the frontal plane, the canines, premolars, and molars were more inclined in adolescents than in adults. In the sagittal plane, a large within-group variability was observed. Clinical crown height was significantly larger in males than in females in all maxillary and mandibular canines, premolars, second molars, maxillary central incisors, and first molars. With age, some degree of dental eruption was found in maxillary and mandibular canines, maxillary second premolars, and molars. The age-related decrease in FACC inclination may be the effect of a progressive buccal and mesial drift.

  17. Measurement of the fluorescence of restorative dental materials using a 655-nm diode laser

    NASA Astrophysics Data System (ADS)

    Zanin, Fatima A. A.; Souza-Campos, Dilma H.; Zanin, Sissi; Brugnera, Aldo, Jr.; Pecora, Jesus D.; Pinheiro, Antonio L. B.; Harari, Sonia

    2001-04-01

    The aim of this study was to determine the level of fluorescence of seven restorative materials using 655 nm diode laser. The laser fluorescence system has ben used as an auxiliary method for the detection of carious lesions. This new diagnostic method increases information which are important for the choice of treatment by the Dentist. The characteristic of restorative materials and sealers interferes in the values obtained by the apparatus during the detection of secondary carious lesions. The optical properties of each biological tissue or material are related to the interaction with the laser beam. Aware of that, the fluorescence of healthy dentin and enamel is 0-15, the authors determined the fluorescence of seven restorative materials with 10 teeth in each group. The laser reading scale differed according to the materia, ranging from 1 to 22 with several materials, for example the sealer without inorganic filler and the glass ionomer, showing fluorescence values similar to carious enamel which interferes with the readings around the restorations resulting in a false positive. Knowledge of restoration material fluorescence can aid in the detection of secondary carious lesions around the restorations.

  18. Knowledge and Awareness among Parents and General Dental Practitioners regarding Rehabilitation with Full Coverage Restoration in Children: A Multi-centric Trial

    PubMed Central

    Saroj, Gyanendra; Sharma, Swati; Gupta, Basant

    2016-01-01

    ABSTRACT Aims: The aim of this study was to evaluate the knowledge and awareness among parents and general dental practitioners regarding rehabilitation with full coverage restoration in children following pulp therapy. Materials and methods: A multiple choice questionnaire was given to 1,000 parents and 400 general practitioners in this multicentric trial. The questionnaire assessed their beliefs, knowledge regarding care of primary teeth, assessment of treating children, and knowledge regarding importance of primary teeth. All the questionnaires were then compiled and statistically analyzed using Statistical Package for Social Sciences (SPSS) software. Results and discussion: 53% parents did not know the importance of primary teeth and 73% parents also thought that no treatment is possible for pulpally involved primary teeth. 20% parents believed that root canal treatment can be possible for children and only 10% knew about full coverage restorations. 40% of the general dentists felt that the best treatment in the case of primary necrotic teeth is extraction and only 13% knew about stainless steel crowns. 62% of general dental practitioners pointed out patients’ noninterest in providing crowns whereas 68% parents reported non-information by dentists. Conclusion: Both parents and general dental practitioners have incomplete and inadequate knowledge regarding full coverage restorations, and we need to improve the knowledge and dental awareness of the parents and the general dental practitioners. How to cite this article: Moda A, Saroj G, Sharma S, Gupta B. Knowledge and Awareness among Parents and General Dental Practitioners regarding Rehabilitation with Full Coverage Restoration in Children: A Multi-centric Trial. Int J Clin Pediatr Dent 2016;9(2):177-180. PMID:27365944

  19. Ester-free Thiol-ene Dental Restoratives – Part A: Resin Development

    PubMed Central

    Podgórski, Maciej; Becka, Eftalda; Claudino, Mauro; Flores, Alexander; Shah, Parag K.; Stansbury, Jeffrey W.; Bowman, Christopher N.

    2015-01-01

    Objectives To detail the development of ester-free thiol-ene dental resins with enhanced mechanical performance, limited potential for water uptake/leachables/degradation and low polymerization shrinkage stress. Methods Thiol-terminated oligomers were prepared via a thiol-Michael reaction and a bulky tetra-allyl monomer containing urethane linkages was synthesized. The experimental oligomers and/or monomers were photopolymerized using visible light activation. Several thiol-ene formulations were investigated and their performance ranked by comparisons of the thermo-mechanical properties, polymerization shrinkage stress, water sorption/solubility, and reactivity with respect to a control comprising a conventional BisGMA/TEGDMA dental resin. Results The ester-free thiol-ene formulations had significantly lower viscosities, water sorption and solubility than the BisGMA/TEGDMA control. Depending on the resin, the limiting functional conversions were equivalent to or greater than that of BisGMA/TEGDMA. At comparable conversions, lower shrinkage stress values were achieved by the thiol-ene systems. The polymerization shrinkage stress was dramatically reduced when the tetra-allyl monomer was used as the ene in ester-free thiol-ene mixtures. Although exhibiting lower Young’s modulus, flexural strength, and glass transition temperatures, the toughness values associated with thiol-ene resins were greater than that of the BisGMA/TEGDMA control. In addition, the thiol-ene polymerization resulted in highly uniform polymer networks as indicated by the narrow tan delta peak widths. Significance Employing the developed thiol-ene resins in dental composites will reduce shrinkage stress and moisture absorption and form tougher materials. Furthermore, their low viscosities are expected to enable higher loadings of functionalized micro/nano-scale filler particles relevant for practical dental systems. PMID:26360013

  20. Evaluation of the Load-bearing Capacity of Fractured Incisal Edge of Maxillary Permanent Central Incisors restored with a Glass Fiber-reinforced Nanocomposite: An in vitro Study

    PubMed Central

    Srilatha, KT; Nandlal, B; Dhull, Kanika Singh

    2015-01-01

    ABSTRACT Objectives: The aim of this study was to evaluate and compare the load-bearing capacity of fractured incisal edge of maxillary permanent central incisors restored with a nanocomposite and a glass fiber-reinforced nanocomposite. Materials and methods: Thirty-six extracted sound maxillary central incisors randomly divided in three groups were used for the present study. Group I (control) contained untreated teeth. Samples in experimental groups II and III were prepared by cutting the incisal (one-third) part of the crown horizontally and subjected to enamel preparations and restored with a nanocomposite and a glass fiber-reinforced nanocomposite respectively. All restored teeth were stored in distilled water at room temperature for 24 hours. Fracture resistance was evaluated as peak load at failure (Newton) for samples tested in a cantilever-bending test using Hounsfield universal testing machine. Failure modes were microscopically examined. Results: Highest mean peak failure load (Newton) among experimental groups was observed in glass fiber-reinforced nano composite group (863.50 ± 76.12 N) followed by nanocomposite group (633.67 ± 40.14 N). One-way analysis of variance (ANOVA) revealed that the restoration technique significantly affected the load-bearing capacity (p < 0.001). Scheffe’s post-hoc comparison test (subset for α = 0.05) revealed that there was significant difference in the mean peak failure load values of nanocomposite and glass fiber-reinforced nanocomposite groups when considered together (p < 0.001). Experimental groups showed similar types of failure modes with majority occurring ascohesive and mixed type. Fifty-eight percent of the teeth in glass fiber-reinforced nanocomposite group fractured below the cementoenamel junction. Conclusion: By using fiber-reinforced composite substructure under conventional composites in the repair of fractured incisors, the load-bearing capacity of the restored incisal edge could be substantially

  1. Recent advances in dental optics - Part I: 3D intraoral scanners for restorative dentistry

    NASA Astrophysics Data System (ADS)

    Logozzo, Silvia; Zanetti, Elisabetta M.; Franceschini, Giordano; Kilpelä, Ari; Mäkynen, Anssi

    2014-03-01

    Intra-oral scanning technology is a very fast-growing field in dentistry since it responds to the need of an accurate three-dimensional mapping of the mouth, as required in a large number of procedures such as restorative dentistry and orthodontics. Nowadays, more than 10 intra-oral scanning devices for restorative dentistry have been developed all over the world even if only some of those devices are currently available on the market. All the existing intraoral scanners try to face with problems and disadvantages of traditional impression fabrication process and are based on different non-contact optical technologies and principles. The aim of this publication is to provide an extensive review of existing intraoral scanners for restorative dentistry evaluating their working principles, features and performances.

  2. The Use of Micro-CT with Image Segmentation to Quantify Leakage in Dental Restorations

    PubMed Central

    Carrera, Carola A.; Lan, Caixia; Escobar-Sanabria, David; Li, Yuping; Rudney, Joel; Aparicio, Conrado; Fok, Alex

    2015-01-01

    Objective To develop a method for quantifying leakage in composite resin restorations after curing, using non-destructive X-ray micro-computed tomography (micro-CT) and image segmentation. Methods Class-I cavity preparations were made in 20 human third molars, which were divided into 2 groups. Group I was restored with Z100 and Group II with Filtek LS. Micro-CT scans were taken for both groups before and after they were submerged in silver nitrate solution (AgNO3 50%) to reveal any interfacial gap and leakage at the tooth restoration interface. Image segmentation was carried out by first performing image correlation to align the before- and after-treatment images and then by image subtraction to isolate the silver nitrate penetrant for precise volume calculation. Two-tailed Student’s t-test was used to analyze the results, with the level of significance set at p<0.05. Results All samples from Group I showed silver nitrate penetration with a mean volume of 1.3 ± 0.7 mm3. In Group II, only 2 out of the 10 restorations displayed infiltration along the interface, giving a mean volume of 0.3 ± 0.3 mm3. The difference between the two groups was statistically significant (p < 0.05). The infiltration showed non-uniform patterns within the interface. Significance We have developed a method to quantify the volume of leakage using non-destructive micro-CT, silver nitrate infiltration and image segmentation. Our results confirmed that substantial leakage could occur in composite restorations that have imperfections in the adhesive layer or interfacial debonding through polymerization shrinkage. For the restorative systems investigated in this study, this occurred mostly at the interface between the adhesive system and the tooth structure. PMID:25649496

  3. Clinical cross-polarization optical coherence tomography assessment of subsurface enamel below dental resin composite restorations.

    PubMed

    Lenton, Patricia; Rudney, Joel; Fok, Alex; Jones, Robert S

    2014-04-01

    A newly designed intraoral swept source cross-polarization optical coherence tomography (CP-OCT) imaging system was used to examine the integrity of the subsurface enamel below resin composite restorations placed in primary teeth. CP-OCT analysis was performed using images obtained from resin composite restoration in 62 ([Formula: see text]) pediatric subjects. Clinical examination was performed by a single examiner prior to CP-OCT imaging and analysis. CP-OCT images are presented using a unique combined intensity image, where a false color scale is overlaid on the grayscale intensity image. There was a clear difference in the distribution of the mean-backscattered intensity (mR) between restorations recently placed and those possessing frank cavitation (Student's t-test, [Formula: see text]). For mR above 15.49 dB, the sensitivity was 80% and specificity 86%. The Youden index J was 0.8 above 12.3 dB where sensitivity was 100% and specificity was 80%. CP-OCT imaging may be used to confirm the subsurface marginal integrity below resin composite restorations but with careful consideration of limitations of the imaging modality. CP-OCT imaging may be a useful adjunct to clinical visual investigation to confirm that a composite margin has a sound and well-adapted interface.

  4. Staining potential of acidulated phosphate fluoride (APF) foam on dental restorations in vitro

    PubMed Central

    Lin, David; Huang, Boyen

    2015-01-01

    Objectives: To identify the staining potential of acidulated phosphate fluoride (APF) foam on restorations in vitro. Materials and Methods: Two hundred ovine molars were used. Except 40 teeth remained unrestored as the controls, each was randomly selected to receive one of four restorative materials including preparation without restoration, glass ionomer cement (GIC), resin modified glass ionomer cement (RMGIC), or composite resin (CR). Following the procedure, topical APF was applied with a predetermined frequency. Staining formation was then evaluated. Results: APF-treated teeth and restorations appeared with a darker shade, an orange-colored surface and/or a brown margin. The staining rates on GIC, RMGIC, and CR were 50%, 27.5%, and 17.5%, respectively. GIC had a higher staining potential than RMGIC (χ2 = 4.266, df = 1, P = 0.039) and CR (χ2 = 9.448, df = 1, P = 0.002), whereas the difference between RMGIC and CR was indiscernible (χ2 = 1.147, df = 1, P = 0.284). Repeated applications of topical APF increased the risk of staining on RMGIC (χ2 = 8.436 df = 1, P = 0.004) and CR (χ2 = 6.873, df = 1, P = 0.009) but not on GIC (χ2 = 0, df = 1, P = 1) and the controls (χ2 = 4.051, df = 3, P = 0.256). Conclusions: APF-foam-related staining was confirmed in vitro. GIC was more susceptible to fluoride staining. This study suggested aesthetic implications when applying fluorides to restored teeth. PMID:25657523

  5. Impact of Technique-Specific Operative Videos on First-Year Dental Students' Performance of Restorative Procedures.

    PubMed

    Patel, Shalizeh A; Barros, Juliana A; Clark, Christina M; Frey, Gary N; Streckfus, Charles F; Quock, Ryan L

    2015-09-01

    The aim of this study was to examine the impact of psychomotor operative video demonstrations on first-year dental students who are performing specific procedures for the first time in a preclinical setting. The class was randomly divided into two groups, and three restorative procedures were selected. On the date on which each procedure was to be performed in the preclinical laboratory for the first time, one group (experimental, n=50) was shown a technique video for that specific procedure immediately before commencing the exercise; the control cohort (n=50) did not view the video. Technical performance on procedures was evaluated by students and two calibrated and blinded examiners. The students' perceptions of the experience were also collected in a survey. All first-year students participated in the study, for a 100% response rate. A Mann-Whitney U test did not show any group differences in technical performance (mean values on preparation: 77.1 vs. 77.8; amalgam: 82.7 vs. 82.8; composite: 79.7 vs. 78.0). A Spearman rho test revealed a significantly higher correlation in 13 out of 25 evaluation categories between student self-assessment and blinded examiner assessment for the experimental group. A chi-square test of questionnaire responses revealed a positive student perception of administering these videos for the preparation (X(2)=4.8, p<0.03), the amalgam restoration (X(2)=12.4, p<0.001), and the composite restoration (X(2)=11.3, p<0.001). The psychomotor video demonstrations did not immediately improve student performance on preclinical operative procedures, but they were well received by students and augmented self-assessment ability. These findings suggest that videos can be a useful teaching aid in a preclinical environment, especially regarding comprehension of concepts. PMID:26329035

  6. Rapid and non-destructive analysis of metallic dental restorations using X-ray fluorescence spectra and light-element sampling tools

    NASA Astrophysics Data System (ADS)

    Furuhashi, K.; Uo, M.; Kitagawa, Y.; Watari, F.

    2012-12-01

    IntroductionRecently, allergic diseases caused by dental metals have been increasing. Therefore, rapid and accurate analytical methods for the metal restorations in the oral cavities of patients are required. The purpose of this study was to develop a non-destructive extraction method for dental alloys, along with a subsequent, rapid and accurate elemental analysis. Materials and methodSamples were obtained by polishing the surfaces of metal restorations using a dental rotating tool with disposable buffs and polishing pastes. As materials for the analysis, three dental alloys were used. To compare the sampling and analysis efficiencies, two buffs and seven pastes were used. After polishing the surface of a metal restoration, the buff was analyzed using X-ray scanning analytical microscopy (XSAM). ResultsThe efficiency of the analysis was judged based on the sampling rate achieved and the absence of disturbing elements in the background in fluorescence X-ray spectra. The best results were obtained for the combination of TexMet as a buff with diamond as a paste. This combination produced a good collection efficiency and a plain background in the fluorescence X-ray spectra, resulting in a high precision of the analysis.

  7. Comparison of acceptance, preference and efficacy between pressure anesthesia and classical needle infiltration anesthesia for dental restorative procedures in adult patients

    PubMed Central

    Makade, Chetana Sachin; Shenoi, Pratima R; Gunwal, Mohit K

    2014-01-01

    Introduction: Intraoral local anesthesia is essential for delivering dental care. Needless devices have been developed to provide anesthesia without injections. Little controlled research is available on its use in dental restorative procedures in adult patients. The aims of this study were to compare adult patients acceptability and preference for needleless jet injection with classical local infiltration as well as to evaluate the efficacy of the needleless anesthesia. Materials and Methods: Twenty non fearful adults with no previous experience of dental anesthesia were studied using split-mouth design. The first procedure was performed with classical needle infiltration anesthesia. The same amount of anesthetic solution was administered using MADA jet needleless device in a second session one week later, during which a second dental restorative procedure was performed. Patients acceptance was assessed using Universal pain assessment tool while effectiveness was recorded using soft tissue anesthesia and pulpal anesthesia. Patients reported their preference for the anesthetic method at the third visit. The data was evaluated using chi square test and student's t-test. Results: Pressure anesthesia was more accepted and preferred by 70% of the patients than traditional needle anesthesia (20%). Both needle and pressure anesthesia was equally effective for carrying out the dental procedures. Conclusion: Patients experienced significantly less pain and fear (p<0.01) during anesthetic procedure with pressure anesthesia. However, for more invasive procedures needle anesthesia will be more effective. PMID:24778516

  8. Effect of Nutritional Habits on Dental Caries in Permanent Dentition among Schoolchildren Aged 10–12 Years: A Zero-Inflated Generalized Poisson Regression Model Approach

    PubMed Central

    ALMASI, Afshin; RAHIMIFOROUSHANI, Abbas; ESHRAGHIAN, Mohammad Reza; MOHAMMAD, Kazem; PASDAR, Yahya; TARRAHI, Mohammad Javad; MOGHIMBEIGI, Abbas; AHMADI JOUYBARI, Touraj

    2016-01-01

    Background: The aim of this study was to assess the associations between nutrition and dental caries in permanent dentition among schoolchildren. Methods: A cross-sectional survey was undertaken on 698 schoolchildren aged 10 to 12 yr from a random sample of primary schools in Kermanshah, western Iran, in 2014. The study was based on the data obtained from the questionnaire containing information on nutritional habits and the outcome of decayed/missing/filled teeth (DMFT) index. The association between predictors and dental caries was modeled using the Zero Inflated Generalized Poisson (ZIGP) regression model. Results: Fourteen percent of the children were caries free. The model was shown that in female children, the odds of being in a caries susceptible sub-group was 1.23 (95% CI: 1.08–1.51) times more likely than boys (P=0.041). Additionally, mean caries count in children who consumed the fizzy soft beverages and sweet biscuits more than once daily was 1.41 (95% CI: 1.19–1.63) and 1.27 (95% CI: 1.18–1.37) times more than children that were in category of less than 3 times a week or never, respectively. Conclusions: Girls were at a higher risk of caries than boys were. Since our study showed that nutritional status may have significant effect on caries in permanent teeth, we recommend that health promotion activities in school should be emphasized on healthful eating practices; especially limiting beverages containing sugar to only occasionally between meals. PMID:27141498

  9. A 24-month Evaluation of Amalgam and Resin-Based Composite Restorations: Findings from The National Dental Practice-Based Research Network

    PubMed Central

    McCracken, Michael S.; Gordan, Valeria V.; Litaker, Mark S.; Funkhouser, Ellen; Fellows, Jeffrey L.; Shamp, Douglass G.; Qvist, Vibeke; Meral, Jeffrey S.; Gilbert, Gregg H.

    2013-01-01

    Background Knowing which factors influence restoration longevity can help clinicians make sound treatment decisions. The authors analyzed data from the National Dental Practice-Based Research Network to identify predictors of early failures of amalgam and resin-based composite (RBC) restorations. Methods This prospective cohort study gathered information from clinicians and offices participating in the network. Clinicians completed a baseline data collection form at the time of restoration placement, and annually thereafter. Data collected included patient factors, practice factors, and dentist factors, and were analyzed using mixed-model logistic regression. Results A total of 226 practitioners followed 6,218 direct restorations in 3,855 patients; 386 restorations failed (6.6 percent) during the mean follow-up period of 23.7 (SD 8.8) months. The number of tooth surfaces restored at baseline predicted subsequent restoration failure; large restorations were over 4 times more likely to fail. Material was not significantly associated with longevity; neither was tooth type. Patient age was highly associated with failure (p<0.0001). The failure rate for children was 5 percent, compared to 12 percent in persons 65 years old or older. Dentist gender and practice workload were significantly associated with restoration longevity. Conclusions In this prospective cohort study, these factors significantly predicted an increased failure rate for amalgam and RBC restorations: older patient age and a higher number of surfaces restored at baseline, with other key baseline variables taken into account. Material choice was not significantly predictive in these early results. Clinical Implications Understanding risk factors for early restoration failure may lead to more-effective patient care. PMID:23729455

  10. Open photoacoustic cell for thermal diffusivity measurements of a fast hardening cement used in dental restoring

    NASA Astrophysics Data System (ADS)

    Astrath, F. B. G.; Astrath, N. G. C.; Baesso, M. L.; Bento, A. C.; Moraes, J. C. S.; Santos, A. D.

    2012-01-01

    Thermal diffusivity and conductivity of dental cements have been studied using open photoacoustic cell (OPC). The samples consisted of fast hardening cement named CER, developed to be a root-end filling material. Thermal characterization was performed in samples with different gel/powder ratio and particle sizes and the results were compared to the ones from commercial cements. Complementary measurements of specific heat and mass density were also performed. The results showed that the thermal diffusivity of CER tends to increase smoothly with gel volume and rapidly against particle size. This behavior was linked to the pores size and their distribution in the samples. The OPC method was shown to be a valuable way in deriving thermal properties of porous material.

  11. FDI World Dental Federation - clinical criteria for the evaluation of direct and indirect restorations. Update and clinical examples.

    PubMed

    Hickel, Reinhard; Peschke, Arnd; Tyas, Martin; Mjör, Ivar; Bayne, Stephen; Peters, Mathilde; Hiller, Karl-Anton; Randall, Ross; Vanherle, Guido; Heintze, Siegward D

    2010-08-01

    In 2007, new clinical criteria were approved by the FDI World Dental Federation and simultaneously published in three dental journals. The criteria were categorized into three groups: esthetic parameters (four criteria), functional parameters (six criteria), and biological parameters (six criteria). Each criterion can be expressed with five scores, three for acceptable and two for non-acceptable (one for reparable and one for replacement). The criteria have been used in several clinical studies since 2007, and the resulting experience in their application has led to a requirement to modify some of the criteria and scores. The two major alterations involve staining and approximal contacts. As staining of the margins and the surface have different causes, both phenomena do not appear simultaneously. Thus, staining has been differentiated into marginal staining and surface staining. The approximal contact now appears under the name "approximal anatomic form" as the approximal contour is a specific, often non-esthetic issue that cannot be integrated into the criterion "esthetic anatomical form". In 2008, a web-based training and calibration tool called e-calib (www.e-calib.info) was made available. Clinical investigators and other research workers can train and calibrate themselves interactively by assessing clinical cases of posterior restorations, which are presented as high quality pictures. Currently, about 300 clinical cases are included in the database which is regularly updated. Training for 8 of the 16 clinical criteria is available in the program: "Surface luster"; "Staining (surface, margins)"; "Color match and translucency"; "Esthetic anatomical form"; "Fracture of material and retention"; "Marginal adaptation"; "Recurrence of caries, erosion, abfraction"; and "Tooth integrity (enamel cracks, tooth fractures)". Typical clinical cases are presented for each of these eight criteria and their corresponding five scores.

  12. FDI World Dental Federation: clinical criteria for the evaluation of direct and indirect restorations-update and clinical examples.

    PubMed

    Hickel, Reinhard; Peschke, Arnd; Tyas, Martin; Mjör, Ivar; Bayne, Stephen; Peters, Mathilde; Hiller, Karl-Anton; Randall, Ross; Vanherle, Guido; Heintze, Siegward D

    2010-08-01

    In 2007, new clinical criteria were approved by the FDI World Dental Federation and simultaneously published in three dental journals. The criteria were categorized into three groups: esthetic parameters (four criteria), functional parameters (six criteria) and biological parameters (six criteria). Each criterion can be expressed with five scores, three for acceptable and two for non-acceptable (one for reparable and one for replacement). The criteria have been used in several clinical studies since 2007, and the resulting experience in their application has led to a requirement to modify some of the criteria and scores. The two major alterations involve staining and approximal contacts. As staining of the margins and the surface has different causes, both phenomena do not appear simultaneously. Thus, staining has been differentiated into marginal staining and surface staining. The approximal contact now appears under the name "approximal anatomic form" as the approximal contour is a specific, often non-esthetic issue that cannot be integrated into the criterion "esthetic anatomical form". In 2008, a web-based training and calibration tool called e-calib ( www.e-calib.info ) was made available. Clinical investigators and other research workers can train and calibrate themselves interactively by assessing clinical cases of posterior restorations which are presented as high-quality pictures. Currently, about 300 clinical cases are included in the database which is regularly updated. Training for eight of the 16 clinical criteria is available in the program: "Surface lustre"; "Staining (surface, margins)"; "Color match and translucency"; Esthetic anatomical form"; "Fracture of material and retention"; "Marginal adaptation"; "Recurrence of caries, erosion, abfraction"; and "Tooth integrity (enamel cracks, tooth fractures)". Typical clinical cases are presented for each of these eight criteria and their corresponding five scores.

  13. The assessment of surface roughness and microleakage of eroded tooth-colored dental restorative materials

    PubMed Central

    Hussein, Thulfiqar Ali; Bakar, Wan Zaripah Wan; Ghani, Zuryati Ab; Mohamad, Dasmawati

    2014-01-01

    Objectives: To investigate the effect of acidic solution on surface roughness and microleakage of tooth-colored restorative materials. Materials and Methods: A 160 box-shaped cavities were prepared on the buccal surfaces of 160 human molars, and assigned to four groups: Group A restored with Ketac™ Molar Easymix, Group B with Fuji II™ LC, Group C with Ketac™ N100, and Group D with Filtek™ Z250, and subdivided into study and control groups (n = 20). Study groups were immersed in lemon juice (pH = 2.79) for 24 h, whilst controlgroups in deionized distilled water. All samples were immersed in 2% methylene blue dye, sectioned into two equal halves for surface roughness, and microleakage tests. Data were analyzed using Mann–Whitney and Kruskal–Wallis tests at P < 0.05. Results: There was a significant difference in surface roughness of Ketac™ Molar, Fuji II™ LC, and Ketac™ N100. No significant difference was found in microleakage of Ketac™ Molar and Fuji II™ LC; however, there were significant differences in the gingival margin of Ketac™ N100, and the occlusal margin of Filtek™ Z250. Conclusions: All glass ionomer cements were eroded after exposure to the acidic drink. Filtek™ Z250 and Ketac™ Molar Easymix showed more microleakage. All materials showed more microleakage at the gingival margins. PMID:25506139

  14. Dental OCT

    NASA Astrophysics Data System (ADS)

    Colston, Bill W.; Sathyam, Ujwal S.; Dasilva, Luiz B.; Everett, Matthew J.; Stroeve, Pieter; Otis, L. L.

    1998-09-01

    We present here the first in vivo optical coherence tomography (OCT) images of human dental tissue. A novel dental optical coherence tomography system has been developed. This system incorporates the interferometer sample arm and transverse scanning optics into a handpiece that can be used intraorally to image human dental tissues. The average imaging depth of this system varied from 3 mm in hard tissues to 1.5 mm in soft tissues. We discuss the application of this imaging system for dentistry and illustrate the potential of our dental OCT system for diagnosis of periodontal disease, detection of caries, and evaluation of dental restorations.

  15. Photopolymerization of a dental nanocomposite as restorative material using the argon laser.

    PubMed

    Mirsasaani, Seyyed Shahabeddin; Atai, Mohammad M; Hasani-Sadrabadi, Mohammad M

    2011-09-01

    The aim of this study was to investigate the effect of power density and irradiation time of an argon laser on the physico-mechanical properties of light-cured dental nanocomposites. The composites were cured with 260 mW/cm(2) and 340 mW/cm(2) power densities at different irradiation times. The degree of conversion (DC), flexural strength, flexural modulus, water sorption, solubility and reaction temperature were measured. The maximum DC (50%), which was achieved after approximately 20 s irradiation, and the reaction temperature rise (20°C) were demonstrated by composite containing 20% filler cured at 340 mW/cm(2). The composite with 25% filler cured at 340 mW/cm(2) showed the highest flexural strength and modulus, which were 32.2 MPa and 1.89 GPa, respectively. The minimum water sorption (3.8%) and solubility (1.2%) were achieved with the composite containing 25% filler cured at 340 mW/cm(2). Finally, the composite with 25% filler cured at 340 mW/cm(2) showed higher physico-mechanical properties.

  16. Effect of artificial saliva contamination on adhesion of dental restorative materials.

    PubMed

    Shimazu, Kisaki; Karibe, Hiroyuki; Ogata, Kiyokazu

    2014-01-01

    The purpose of this study was to evaluate the effects of artificial saliva contamination on three restorative materials, namely, a glass ionomer cement (GIC), a resin-modified GIC (RMGIC), and a composite resin (CR), for which two different etching adhesive systems were used. Thus, three surface conditions were created on bovine teeth using artificial saliva: control, mild saliva contamination, and severe saliva contamination. The dentin bond strength for CR was significantly lower after artificial saliva contamination. There were, however, no significant differences among the three surface conditions in terms of the dentin and enamel bond strengths of GIC and RMGIC. Moreover, CR exhibited significantly greater microleakage after artificial saliva contamination, whereas no significant differences were found in GIC and RMGIC. The results showed that artificial saliva contamination did not affect the shear bond strengths of GIC and RMGIC or their degrees of microleakage.

  17. Improving flexural strength of dental restorative ceramics using laser interference direct structuring

    SciTech Connect

    Daniel, Claus; Drummond, James; Giordano, Russell A.

    2008-01-01

    Zirconia and alumina ceramics restorative materials were treated with laser interference direct structuring using the third harmonic of a short pulse Nd:YAG and tested in a three-point bending test to measure the flexural strength. The surface was restructured in a periodic line like pattern with controlled surface porosity and a surface composite pattern. The composite consist of two different defect states rather than different phase compositions. The resulting mechanical properties are a function of the number of laser pulses, laser energy, and angle in between the laser beams defining the periodic feature distance. This composite effect is comparable with a laminate showing increasing stiffness with decreasing layer thickness. The material s fracture strength could be controlled through the three mentioned laser parameters and in an initial study significantly improved by up to 50% from initial 422 MPa to 630 MPa for alumina and 833 MPa to 1250 MPa for zirconia.

  18. Highly-translucent, strong and aging-resistant 3Y-TZP ceramics for dental restoration by grain boundary segregation.

    PubMed

    Zhang, Fei; Vanmeensel, Kim; Batuk, Maria; Hadermann, Joke; Inokoshi, Masanao; Van Meerbeek, Bart; Naert, Ignace; Vleugels, Jef

    2015-04-01

    Latest trends in dental restorative ceramics involve the development of full-contour 3Y-TZP ceramics which can avoid chipping of veneering porcelains. Among the challenges are the low translucency and the hydrothermal stability of 3Y-TZP ceramics. In this work, different trivalent oxides (Al2O3, Sc2O3, Nd2O3 and La2O3) were selected to dope 3Y-TZP ceramics. Results show that dopant segregation was a key factor to design hydrothermally stable and high-translucent 3Y-TZP ceramics and the cation dopant radius could be used as a controlling parameter. A large trivalent dopant, oversized as compared to Zr(4+), exhibiting strong segregation at the ZrO2 grain boundary was preferred. The introduction of 0.2 mol% La2O3 in conventional 0.1-0.25 wt.% Al2O3-doped 3Y-TZP resulted in an excellent combination of high translucency and superior hydrothermal stability, while retaining excellent mechanical properties.

  19. Anesthetic management of comprehensive dental restoration in a child with glutaric aciduria type 1 using volatile sevoflurane.

    PubMed

    Teng, Wei-Nung; Lin, Su-Man; Niu, Dau-Ming; Kuo, Yi-Min; Chan, Kwok-Hon; Sung, Chun-Sung

    2014-10-01

    Glutaric aciduria type 1 (GA1) is a rare, inherited mitochondrial disorder that results from deficiency of mitochondrial glutaryl-CoA dehydrogenase. Most patients develop neurological dysfunction early in life, which leads to severe disabilities. We present a 37-month-old girl with GA1 manifested as macrocephaly and hypotonia who received comprehensive dental restoration surgery under general anesthesia with sevoflurane. She was placed on specialized fluid management during a preoperative fasting period and anesthesia was administered without complications. All the physiological parameters, including glucose and lactate blood levels and arterial blood gas were carefully monitored and maintained within normal range perioperatively. Strategies for anesthetic management should include prevention of pulmonary aspiration, dehydration, hyperthermia and catabolic state, adequate analgesia to minimize surgical stress, and avoidance of prolonged neuromuscular blockade. We administered general anesthesia with sevoflurane uneventfully, which was well tolerated by our patient with GA1. Additionally, communication with a pediatric geneticist and surgeons should be undertaken to formulate a comprehensive anesthetic strategy in these patients.

  20. Study of the surface wear resistance and biological properties of the Ti-Zr-Nb-Sn alloy for dental restoration.

    PubMed

    Hu, Xin; Wei, Qiang; Li, Chang-Yi; Deng, Jia-Yin; Liu, Shuang; Zhang, Lian-Yun

    2010-10-01

    A new titanium alloy (Ti-12.5Zr-3Nb-2.5Sn) was developed to meet the needs of clinical requirements for medical titanium alloys and improve the properties of existing titanium alloys. The as-prepared alloy was solution treated at 500 °C for 3 h in vacuum followed by water quenching. Tensile, wear and hardness tests were carried out to examine the mechanical properties of the Ti-Zr-Nb-Sn alloy. Oral mucous membrane irritation test was performed to evaluate the surface biological properties of the Ti-Zr-Nb-Sn alloy. The results suggested that the surface hardness and wear-resistant properties of the Ti-12.5Zr-3Nb-2.5Sn alloy were superior to commercially pure Ti. The oral mucous irritation test showed that all samples had no mucous membrane irritation. It indicates that Ti-12.5Zr-3Nb-2.5Sn has large potential to be used as dental restoration material.

  1. Crack tip fracture toughness of base glasses for dental restoration glass-ceramics using crack opening displacements.

    PubMed

    Deubener, J; Höland, M; Höland, W; Janakiraman, N; Rheinberger, V M

    2011-10-01

    The critical stress intensity factor, also known as the crack tip toughness K(tip), was determined for three base glasses, which are used in the manufacture of glass-ceramics. The glasses included the base glass for a lithium disilicate glass-ceramic, the base glass for a fluoroapatite glass-ceramic and the base glass for a leucite glass-ceramic. These glass-ceramic are extensively used in the form of biomaterials in restorative dental medicine. The crack tip toughness was established by using crack opening displacement profiles under experimental conditions. The crack was produced by Vickers indentation. The crack tip toughness parameters determined for the three glass-ceramics differed quite significantly. The crack tip parameters of the lithium disilicate base glass and the leucite base glass were higher than that of the fluoroapatite base glass. This last material showed glass-in-glass phase separation. The discussion of the results clearly shows that the droplet glass phase is softer than the glass matrix. Therefore, the authors conclude that a direct relationship exists between the chemical nature of the glasses and the crack tip parameter.

  2. Preparation and evaluation of a high-strength biocompatible glass-ionomer cement for improved dental restoratives.

    PubMed

    Xie, D; Zhao, J; Yang, Y; Park, J; Chu, T M; Zhang, J T

    2008-06-01

    We have developed a high-strength light-cured glass-ionomer cement (LCGIC). The polymer in the cement was composed of the 6-arm star-shape poly(acrylic acid) (PAA), which was synthesized using atom-transfer radical polymerization. The polymer was used to formulate with water and Fuji II LC filler to form LCGIC. Compressive strength (CS) was used as a screening tool for evaluation. Commercial glass-ionomer cement Fuji II LC was used as control. The results show that the 6-arm PAA polymer exhibited a lower viscosity in water as compared to its linear counterpart that was synthesized via conventional free-radical polymerization. This new LCGIC system was 48% in CS, 77% in diametral tensile strength, 95% in flexural strength and 59% in fracture toughness higher but 93.6% in shrinkage lower than Fuji II LC. An increasing polymer content significantly increased CS, whereas an increasing glass filler content increased neither yield strength nor ultimate CS except for modulus. During aging, the experimental cement showed a significant and continuous increase in yield strength, modulus and ultimate CS, but Fuji II LC only showed a significant increase in strength within 24 h. The experimental cement was very biocompatible in vivo to bone and showed little in vitro cytotoxicity. It appears that this novel LCGIC cement will be a better dental restorative because it demonstrated significantly improved mechanical strengths and better in vitro and in vivo biocompatibilities as compared to the current commercial LCGIC system.

  3. Chipping fracture resistance of dental CAD/CAM restorative materials: Part 2. Phenomenological model and the effect of indenter type

    PubMed Central

    Quinn, G.D.; Giuseppetti, A.A.; Hoffman, K.H.

    2014-01-01

    The edge chipping resistances of six CAD/CAM dental restoration materials are analyzed and correlated to other mechanical properties. A new quadratic relationship that is based on a phenomenological model is presented. Objective The purpose of this study was to further analyze the edge chipping resistance of the brittle materials evaluated in Part 1. One objective was to determine why some force-distance trends were linear and others were nonlinear. A second objective was to account for differences in chipping resistance with indenter type. Methods Edge chipping experiments were conducted with different indenters, including some custom-made sharp conical indenters. A new force – distance quadratic expression was correlated to the data and compared to the linear and power law trends. Results The new quadratic function was an excellent fit in every instance. It can account for why some materials can be fit by a linear trend, while others can be fit by the power law trend. The effects of indenter type are accounted for variations in crack initiation and by the wedging stresses once an indentation hole is created. Significance The new quadratic force – edge distance function can be used with edge chipping data for all brittle materials, not just those evaluated in this study. The data trends vary from linear to nonlinear depending upon the material’s hardness, fracture toughness, and elastic modulus. PMID:24685179

  4. Identification through X-ray fluorescence analysis of dental restorative resin materials: a comprehensive study of noncremated, cremated, and processed-cremated individuals.

    PubMed

    Bush, Mary A; Miller, Raymond G; Prutsman-Pfeiffer, Jennifer; Bush, Peter J

    2007-01-01

    Tooth-colored restorative materials are increasingly being placed in the practice of modern dentistry, replacing traditional materials such as amalgam. Many restorative resins have distinct elemental compositions that allow identification of brand. Not only are resins classifiable by elemental content, but they also survive extreme conditions such as cremation. This is of significance to the forensic odontologist because resin uniqueness adds another level of certainty in victim identification, especially when traditional means are exhausted. In this three-part study, unique combinations of resins were placed in six human cadavers (total 70 restorations). Simulated ante-mortem dental records were created. In a blind experiment, a portable X-ray fluorescence (XRF) unit was used to locate and identify the resin brands placed in the dentition. The technique was successful in location and brand identification of 53 of the restorations, which was sufficient to enable positive victim identification among the study group. This part of the experiment demonstrated the utility of portable XRF in detection and analysis of restorative materials for victim identification in field or morgue settings. Identification of individuals after cremation is a more difficult task, as the dentition is altered by shrinkage and fragmentation, and may not be comparable with a dental chart. Identification of processed cremains is a much greater challenge, as comminution obliterates all structural relationships. Under both circumstances, it is the nonbiological artifacts that aid in identification. Restorative resin fillings can survive these conditions, and can still be named by brand utilizing elemental analysis. In a continuation of the study, the cadavers were cremated in a cremation retort under standard mortuary conditions. XRF was again used to analyze retrieved resins and to identify the individuals based on restorative materials known to exist from dental records. The cremains were

  5. Identification through X-ray fluorescence analysis of dental restorative resin materials: a comprehensive study of noncremated, cremated, and processed-cremated individuals.

    PubMed

    Bush, Mary A; Miller, Raymond G; Prutsman-Pfeiffer, Jennifer; Bush, Peter J

    2007-01-01

    Tooth-colored restorative materials are increasingly being placed in the practice of modern dentistry, replacing traditional materials such as amalgam. Many restorative resins have distinct elemental compositions that allow identification of brand. Not only are resins classifiable by elemental content, but they also survive extreme conditions such as cremation. This is of significance to the forensic odontologist because resin uniqueness adds another level of certainty in victim identification, especially when traditional means are exhausted. In this three-part study, unique combinations of resins were placed in six human cadavers (total 70 restorations). Simulated ante-mortem dental records were created. In a blind experiment, a portable X-ray fluorescence (XRF) unit was used to locate and identify the resin brands placed in the dentition. The technique was successful in location and brand identification of 53 of the restorations, which was sufficient to enable positive victim identification among the study group. This part of the experiment demonstrated the utility of portable XRF in detection and analysis of restorative materials for victim identification in field or morgue settings. Identification of individuals after cremation is a more difficult task, as the dentition is altered by shrinkage and fragmentation, and may not be comparable with a dental chart. Identification of processed cremains is a much greater challenge, as comminution obliterates all structural relationships. Under both circumstances, it is the nonbiological artifacts that aid in identification. Restorative resin fillings can survive these conditions, and can still be named by brand utilizing elemental analysis. In a continuation of the study, the cadavers were cremated in a cremation retort under standard mortuary conditions. XRF was again used to analyze retrieved resins and to identify the individuals based on restorative materials known to exist from dental records. The cremains were

  6. Flexural strength of dental composite restoratives: comparison of biaxial and three-point bending test.

    PubMed

    Chung, S M; Yap, A U J; Chandra, S P; Lim, C T

    2004-11-15

    This study compared two test methods used to evaluate the flexural strength of resin-based dental composites. The two test methods evaluated were the three-point bending test4 and the biaxial flexural test. Materials used in this investigation were from the same manufacturer (3M ESPE) and included microfill (A110), minifill (Z100 and Filtek Z250), polyacid modified (F2000), and flowable [Filtek Flowable (FF)] composites. Flexural strength was determined with the use of both test methods after 1 week of conditioning in water at 37 degrees C. Data were analyzed with the use of an ANOVA/Scheffe test and an independent-samples t test at significance level 0.05. Mean flexural strength (n = 7) ranged from 66.61 to 147.21 and 67.27 to 182.81 MPa for three-point bending and ball-on-three-ball biaxial test methods, respectively. In both test methods, Z100 was significantly stronger than all other composites evaluated. In the three-point bending test, flexural strength of Z250 was significantly higher than A110, F2000 and FF, and FF was significantly stronger than A110 and F2000. The biaxial test method arrived at the same conclusions except that there was no significant difference between Z250 and FF. Pearson's correlation revealed a significantly (p < 0.01) positive and good correlation (R2 = 0.72) in flexural strength between the two test methods. Although the biaxial test has the advantage of utilizing small specimens, the low reproducibility of this test method does not support the proposition that it is a more reliable test method when compared to the ISO three-point bending test. PMID:15386492

  7. Oral diagnosis and treatment planning: part 5. Preventive and treatment planning for dental caries.

    PubMed

    Yip, K; Smales, R

    2012-09-01

    The practice of operative dentistry continues to evolve, to reflect the many changes occurring in society and in dental diseases and conditions. However, the belief that all questionable and early carious lesions should be restored still persists. This belief is largely based upon the concept that the removal of all carious tissue followed by meticulous restoration of the tooth is the treatment of choice for dental caries. Yet restorations are not permanent and do not cure caries, as the causes remain. On the other hand, preventive measures can remove or partially remove the causes, thereby reducing the risks for future caries recurrence at the same site or elsewhere in the mouth.

  8. The incorporation of nanoparticles into conventional glass-ionomer dental restorative cements.

    PubMed

    Gjorgievska, Elizabeta; Van Tendeloo, Gustaaf; Nicholson, John W; Coleman, Nichola J; Slipper, Ian J; Booth, Samantha

    2015-04-01

    Conventional glass-ionomer cements (GICs) are popular restorative materials, but their use is limited by their relatively low mechanical strength. This paper reports an attempt to improve these materials by incorporation of 10 wt% of three different types of nanoparticles, aluminum oxide, zirconium oxide, and titanium dioxide, into two commercial GICs (ChemFil® Rock and EQUIA™ Fil). The results indicate that the nanoparticles readily dispersed into the cement matrix by hand mixing and reduced the porosity of set cements by filling the empty spaces between the glass particles. Both cements showed no significant difference in compressive strength with added alumina, and ChemFil® Rock also showed no significant difference with zirconia. By contrast, ChemFil® Rock showed significantly higher compressive strength with added titania, and EQUIA™ Fil showed significantly higher compressive strength with both zirconia and titania. Fewer air voids were observed in all nanoparticle-containing cements and this, in turn, reduced the development of cracks within the matrix of the cements. These changes in microstructure provide a likely reason for the observed increases in compressive strength, and overall the addition of nanoparticles appears to be a promising strategy for improving the physical properties of GICs.

  9. Decisions about restorative dental treatment among dentists attending a postgraduate continuing professional development course.

    PubMed

    Maidment, Y; Durey, K; Ibbetson, R

    2010-11-01

    Continuing professional development (CPD) courses seek to inform, educate and develop practitioners' patterns of prescribing in line with the evidence base. When devising such courses it would be useful for organisers to have some idea of what current practice is and the decision-making process as this would inform the development of appropriate continuing education courses. A questionnaire comprising ten questions was given to 90 dentists at the start of a day's lecture course run under Section 63 regulations. The dentists were then shown a series of pictures and asked how they would manage each of the cases presented. Eighty-nine dentists completed the questionnaire and the results were tabulated and fed back to the group at the end of their day's course. Results showed varied and inconsistent application of advances in restorative techniques among the respondents. Despite a definite interest in more modern treatment options, many practitioners continued to support the use of traditional techniques that could be considered outdated. Further investigation of the practices of GDPs and their decision-making processes would be useful in targeting postgraduate education programmes to encourage the uptake of evidence-based practice.

  10. Substance P incorporation in calcium phosphate cement for dental alveolar bone defect restoration.

    PubMed

    Wang, Tianjue; Wu, Di; Li, Yuan; Li, Wantao; Zhang, Shuyin; Hu, Kaijin; Zhou, Hongzhi

    2016-12-01

    A combination of osteoinductive neuropeptide substance P (SP) and osteoconductive bone cement of calcium phosphate (CPC) might provide an effective and lower-cost solution for complex alveolar bone defects restoration. The present study aims to investigate the key design considerations of SP delivery in CPC. In this study, CPC-based modular scaffolds were developed, where collagen type I was used as accessory organic ingredient to modulate the physical and biological characters. SP was directly mixed in the cement as free peptides, or was covalently immobilized with collagen component. The structural and mechanical properties of the scaffolds were assessed in vitro, and their osteogenic ability was observed in a rabbit model with alveolar bone defect. The results showed that SP could enhance the osteo-conductivity/inductivity of CPC. Collagen solution optimized biocompatibility of CPC, and meanwhile exhibited additive effects on the functions of SP. Nevertheless, immobilization of SP with collagen blocked their bioactivity in CPC. Collagen sponges created macro-porosity in CPC and achieved maximum bone ingrowth with the aid of SP. In conclusion, the present study primarily demonstrated that CPC scaffold can be functionalized by synthetic SP, and the biocompatibility and porosity of the scaffold are adaptable key factors determining their final osteogenic activities. PMID:27612746

  11. [Tooth color matching systems and communication with dental laboratory in indirect restorations: 2011 update].

    PubMed

    Ginzburg, M; Gilboa, I

    2012-01-01

    There has been many technological developments in the last decade. Today's shade-matching technologies have been developed in an effort to increase the success of color matching, communication, reproduction and verification in clinical dentistry and, ultimately, to increase the efficiency of esthetic restorative work within any practice. In general, the output of the color measurements can be classified and specified in several ways. The most common systems for describing color are Munsell's System and the international Commission on Illumination (CIE) L a b color system. Albert Munsell described color as a three-dimensional phenomenon. He described the three dimensions as hue, value (brightness), and chroma (saturation). Visual colour determination by comparison of teeth and shade guides is the most frequently applied method in dentistry. Vitapan Classical (Vita Zahnfabrik, Germany) and its derivations(evidence-based Vitapan 3D-Master shade guide and Linearguide) are the most commonly used shade guides. However, several factors can influence consistency of visual colour selection and specification: individual colour matching ability may vary, the colour perception of any individual may show temporal variation, the range of shades available is inadequate and does not cover the complete colour space of natural teeth, the shade guide tabs are not systematically distributed in their colour space, and changes in lighting conditions can cause alterations in perceived colour. instruments for clinical shade-matching encompass spectrophotometers, colorimeters and digital imaging systems. It can be concluded that different devices have different accuracy and precision. Colorimeters are significantly less reliable than spectrophotometers and digital cameras. Benefits and limitations exist, and the clinician must consider how the technology relates to expectations and needs. Combination of visual colour determination (Vitapan 3D-Master shade guide and Linearguide) with

  12. Atomic force microscopy in vitro study of surface roughness and fractal character of a dental restoration composite after air-polishing

    PubMed Central

    2010-01-01

    Background Surface roughness is the main factor determining bacterial adhesion, biofilm growth and plaque formation on the dental surfaces in vivo. Air-polishing of dental surfaces removes biofilm but can also damage the surface by increasing its roughness. The purpose of this study was to investigate the surface damage of different conditions of air-polishing performed in vitro on a recently introduced dental restorative composite. Methods Abrasive powders of sodium bicarbonate and glycine, combined at different treatment times (5, 10 and 30 s) and distances (2 and 7 mm), have been tested. The resulting root mean square roughness of the surfaces has been measured by means of atomic force microscopy, and the data have been analyzed statistically to assess the significance. Additionally, a fractal analysis of the samples surfaces has been carried out. Results The minimum surface roughening was obtained by air-polishing with glycine powder for 5 s, at either of the considered distances, which resulted in a mean roughness of ~300 nm on a 30 × 30 μm2 surface area, whereas in the other cases it was in the range of 400-750 nm. Both untreated surfaces and surfaces treated with the maximum roughening conditions exhibited a fractal character, with comparable dimension in the 2.4-2.7 range, whereas this was not the case for the surfaces treated with the minimum roughening conditions. Conclusions For the dental practitioner it is of interest to learn that use of glycine in air polishing generates the least surface roughening on the considered restorative material, and thus is expected to provide the lowest rate of bacterial biofilm growth and dental plaque formation. Furthermore, the least roughening behaviour identified has been correlated with the disappearance of the surface fractal character, which could represent an integrative method for screening the air polishing treatment efficacy. PMID:20939880

  13. Increased mercury release from dental amalgam restorations after exposure to electromagnetic fields as a potential hazard for hypersensitive people and pregnant women.

    PubMed

    Mortazavi, Ghazal; Mortazavi, S M J

    2015-01-01

    Over the past decades, the use of common sources of electromagnetic fields such as Wi-Fi routers and mobile phones has been increased enormously all over the world. There is ongoing concern that exposure to electromagnetic fields can lead to adverse health effects. It has recently been shown that even low doses of mercury are capable of causing toxicity. Therefore, efforts are initiated to phase down or eliminate the use of mercury amalgam in dental restorations. Increased release of mercury from dental amalgam restorations after exposure to electromagnetic fields such as those generated by MRI and mobile phones has been reported by our team and other researchers. We have recently shown that some of the papers which reported no increased release of mercury after MRI, may have some methodological errors. Although it was previously believed that the amount of mercury released from dental amalgam cannot be hazardous, new findings indicate that mercury, even at low doses, may cause toxicity. Based on recent epidemiological findings, it can be claimed that the safety of mercury released from dental amalgam fillings is questionable. Therefore, as some individuals tend to be hypersensitive to the toxic effects of mercury, regulatory authorities should re-assess the safety of exposure to electromagnetic fields in individuals with amalgam restorations. On the other hand, we have reported that increased mercury release after exposure to electromagnetic fields may be risky for the pregnant women. It is worth mentioning that as a strong positive correlation between maternal and cord blood mercury levels has been found in some studies, our findings regarding the effect of exposure to electromagnetic fields on the release of mercury from dental amalgam fillings lead us to this conclusion that pregnant women with dental amalgam fillings should limit their exposure to electromagnetic fields to prevent toxic effects of mercury in their fetuses. Based on these findings, as infants

  14. Restored viability and function of dental pulp cells on poly-methylmethacrylate (PMMA)-based dental resin supplemented with N-acetyl cysteine (NAC).

    PubMed

    Kojima, N; Yamada, M; Paranjpe, A; Tsukimura, N; Kubo, K; Jewett, A; Ogawa, T

    2008-12-01

    This study examines cytotoxicity of poly-methylmethacrylate (PMMA)-based dental temporary filling resin to dental pulp cells, and the potential amelioration of the toxicity with an anti-oxidant amino-acid, N-acetyl cysteine (NAC). Dental pulp cells extracted from rat maxillary incisors were cultured on the resin material with or without NAC incorporation, or on the polystyrene. The cultures were supplied with osteoblastic media, containing dexamethasone. Forty five percent of cells on the PMMA dental resin were necrotic at 24h after seeding. However, this percentage was reduced to 27% by incorporating NAC in the resin, which was the level equivalent to that in the culture on polystyrene. The culture on the untreated resin was found to be negative for alkaline phosphate (ALP) activity at days 5 and 10 or von Kossa mineralized nodule formation at day 20. In contrast, some areas of the cultures on NAC-incorporated resin substrates were ALP and von Kossa positive. Collagen I and dentin sialoprotein genes were barely expressed in day 7 culture on the untreated resin. However, those genes were expressed in the culture on the resin with NAC. These results suggest that the decreased cell viability and the nearly completely suppressed odontoblast-like cell phenotype of dental pulp cells cultured on PMMA dental resin can be salvaged to a biologically significant degree by the incorporation of NAC in the resin.

  15. Utilization of dental general anaesthesia for children.

    PubMed

    Karim, Zarina Abdul; Musa, Normaizura; Noor, Siti Noor Fazliah Mohd

    2008-07-01

    Dental treatment under general anaesthesia may be needed for some children and adolescents due to medical or behaviour problem. The objective of the study is to identify the type of treatment that has been carried out under GA in Hospital Universiti Sains Malaysia (HUSM). A retrospective record review study from hospital records of dental patients (under 18 years old) receiving dental treatment under GA from 2003 until 2007 were retrieved from the database. Information such as the reason for GA, and the type of treatment provided was recorded in data sheet. The data were analyzed using SPSS 12.0.1 for Windows. It was checked and verified for errors. A total of 349 cases were treated of which 43.6% had medical problems. Patients were mostly diagnosed to have rampant caries (77.1%) and some of them have behavioural problems (34.4%). Treatment pattern in deciduous dentition revealed more extraction (97.8%) as compared to restoration (75.7%) whereas in permanent dentition more restoration was done (24.3%) as compared to extraction (2.2%). Majority of the restorations were done using Glass Ionomer Cements (47.5%). Biopsy (4.3%) contributed mainly to the surgery (24.1%) done during GA. General anesthesia is necessary when dental disease is interfering with health and general well-being of patient and it can facilitated dental treatment allowing dentists to benefit from improved treatment conditions and provide a higher quality of care. PMID:22570587

  16. Posterior composite restoration update: focus on factors influencing form and function.

    PubMed

    Bohaty, Brenda S; Ye, Qiang; Misra, Anil; Sene, Fabio; Spencer, Paulette

    2013-01-01

    Restoring posterior teeth with resin-based composite materials continues to gain popularity among clinicians, and the demand for such aesthetic restorations is increasing. Indeed, the most common aesthetic alternative to dental amalgam is resin composite. Moderate to large posterior composite restorations, however, have higher failure rates, more recurrent caries, and increased frequency of replacement. Investigators across the globe are researching new materials and techniques that will improve the clinical performance, handling characteristics, and mechanical and physical properties of composite resin restorative materials. Despite such attention, large to moderate posterior composite restorations continue to have a clinical lifetime that is approximately one-half that of the dental amalgam. While there are numerous recommendations regarding preparation design, restoration placement, and polymerization technique, current research indicates that restoration longevity depends on several variables that may be difficult for the dentist to control. These variables include the patient's caries risk, tooth position, patient habits, number of restored surfaces, the quality of the tooth-restoration bond, and the ability of the restorative material to produce a sealed tooth-restoration interface. Although clinicians tend to focus on tooth form when evaluating the success and failure of posterior composite restorations, the emphasis must remain on advancing our understanding of the clinical variables that impact the formation of a durable seal at the restoration-tooth interface. This paper presents an update of existing technology and underscores the mechanisms that negatively impact the durability of posterior composite restorations in permanent teeth.

  17. Central Anticholinergic Syndrome due to Hypoxia-Induced Bradycardia in a Child with Difficult Intubation Undergoing Complete Dental Restoration: A Case Report.

    PubMed

    Gharavifard, Mohamad; Razavi, Majid; Ghandehari Motlagh, Mehdi; Ziyaeifard, Mohsen

    2014-09-01

    Central anticholinergic syndrome (CAS) following general anesthesia (GA) is a well known syndrome in children and adults. Many cases of CAS have been previously reported in the literature. However, there are only two reports of post resuscitation CAS after administration of small doses of atropine. Hereby, we report a case of CAS in a child undergoing complete dental restoration under GA after receiving a small dose of atropine to reverse hypoxia induced bradycardia. Intraoperative events such as hypoxia or cardiac arrest may play a role as triggers for CAS. However, we cannot establish a causal relationship between the occurrence of CAS and such critical events.

  18. Evaluation of the effect of tooth and dental restoration material on electron dose distribution and production of photon contamination in electron beam radiotherapy.

    PubMed

    Bahreyni Toossi, Mohammad Taghi; Ghorbani, Mahdi; Akbari, Fatemeh; Mehrpouyan, Mohammad; Sobhkhiz Sabet, Leila

    2016-03-01

    The aim of this study is to evaluate the effect of tooth and dental restoration materials on electron dose distribution and photon contamination production in electron beams of a medical linac. This evaluation was performed on 8, 12 and 14 MeV electron beams of a Siemens Primus linac. MCNPX Monte Carlo code was utilized and a 10 × 10 cm(2) applicator was simulated in the cases of tooth and combinations of tooth and Ceramco C3 ceramic veneer, tooth and Eclipse alloy and tooth and amalgam restoration materials in a soft tissue phantom. The relative electron and photon contamination doses were calculated for these materials. The presence of tooth and dental restoration material changed the electron dose distribution and photon contamination in phantom, depending on the type of the restoration material and electron beam's energy. The maximum relative electron dose was 1.07 in the presence of tooth including amalgam for 14 MeV electron beam. When 100.00 cGy was prescribed for the reference point, the maximum absolute electron dose was 105.10 cGy in the presence of amalgam for 12 MeV electron beam and the maximum absolute photon contamination dose was 376.67 μGy for tooth in 14 MeV electron beam. The change in electron dose distribution should be considered in treatment planning, when teeth are irradiated in electron beam radiotherapy. If treatment planning can be performed in such a way that the teeth are excluded from primary irradiation, the potential errors in dose delivery to the tumour and normal tissues can be avoided.

  19. Biaxial flexure strength and low temperature degradation of Ce-TZP/Al2O3 nanocomposite and Y-TZP as dental restoratives.

    PubMed

    Ban, Seiji; Sato, Hideo; Suehiro, Yasuhiko; Nakanishi, Hideo; Nawa, Masahiro

    2008-11-01

    The purpose of the present study was to evaluate the mechanical durability of a zirconia/alumina nanocomposite stabilized with cerium oxide (Ce-TZP/Al(2)O(3) nanocomposite) in comparison to yttria-stabilized tetragonal zirconia polycrystals (Y-TZP) and discuss its application on ceramic dental restorations. The disk-shaped specimens of both materials were stored in physiological saline solution at 80 degrees C for 30 days, in 4% acetic acid at 80 degrees C for 30 days, and in an autoclave at 121 degrees C for 10 days. Before and after storage, specimens were subjected to the biaxial flexure test and to the determination of the monoclinic zirconia content. After autoclaving, Y-TZP showed remarkable increasing of the content of monoclinic zirconia: 0.3 vol % before and 49.9 vol % after, and slight decreasing of biaxial flexure strength: 1046 MPa before and 892 MPa after; whereas Ce-TZP/Al(2)O(3) nanocomposite showed no significant difference in the monoclinic content (4.8-5.5 vol %) and the biaxial flexure strength (1371-1422 MPa) after storage in any conditions. It is concluded that, compared to Y-TZP, the Ce-TZP/Al(2)O(3) nanocomposite has a high biaxial flexure strength along with a satisfactory durability in terms of low-temperature aging degradation in above conditions. This study indicates that the Ce-TZP/Al(2)O(3) nanocomposite demonstrates excellent mechanical durability for dental restorations such as all-ceramic bridges.

  20. [Multiple agenesis and prosthetic restoration].

    PubMed

    Renault, P

    1990-03-01

    Cases of multiple agenesia present some difficulties in the treatment planing. Three situations may be encountered: limited agenesia, restored by a fixed, bonded or cemented prosthesis, multiple uni- or bimaxillary agenesia without remaining of deciduous teeth, restored by a fixed, bonded or cemented prosthesis or the partial adjacent prosthesis, multiple uni- or bimaxillary agenesia with remaining of deciduous teeth, restored by means of a supra-dental prosthesis. The first two situations have been described in dental literature and are relatively easy to treat. The same is not true for the third situation, where the decision to keep the temporary teeth considerably increases the difficulty of prosthetic restoration. This subject will be illustrated by the presentation of a clinical case of multiple bi-maxillary agenesia. The patient has: on the maxilla: an absence of 9 permanent teeth (18, 15, 14, 12, 22, 23, 24, 25, 28) and the presence of 4 deciduous teeth (62, 63, 64, 65), on the mandible: an absence of all permanent teeth, with the exception of 36 and 46, and the remaining of 4 deciduous teeth (75, 73, 83, 84). The remaining of deciduous teeth and the presence of a very high inter-arch space led to opting for dental coverage so as to keep the deciduous teeth and a proper vertical dimension. The patient wished to solve his "problem" in the maxilla first, and is not wanting to undergo the extraction of his deciduous teeth. The following therapeutic proposal was adapted: On the maxilla, a three-step procedure: first step: building of metal copings on 13, 16 and 26 and metal-ceramic crowns on 11 and 21, second step: building of telescop crowns on 16 and 26 and clasps on 13, 11 and 21, third step: casting of the removable partial denture framework and soldering to the telescop crowns and clasps. On the mandible, a provisional restoration using a supra-dental resin removable partial denture with ceramic occlusal surfaces was adopted. The aesthetic and functional

  1. Diagnostic Imaging for Dental Implant Therapy

    PubMed Central

    Nagarajan, Aishwarya; Perumalsamy, Rajapriya; Thyagarajan, Ramakrishnan; Namasivayam, Ambalavanan

    2014-01-01

    Dental implant is a device made of alloplastic (foreign) material implanted into the jaw bone beneath the mucosal layer to support a fixed or removable dental prosthesis. Dental implants are gaining immense popularity and wide acceptance because they not only replace lost teeth but also provide permanent restorations that do not interfere with oral function or speech or compromise the self-esteem of a patient. Appropriate treatment planning for replacement of lost teeth is required and imaging plays a pivotal role to ensure a satisfactory outcome. The development of pre-surgical imaging techniques and surgical templates helps the dentist place the implants with relative ease. This article focuses on various types of imaging modalities that have a pivotal role in implant therapy. PMID:25379354

  2. Treatment of traumatic injuries in the front teeth: restorative aspects in crown fractures.

    PubMed

    Dietschi, D; Jacoby, T; Dietschi, J M; Schatz, J P

    2000-10-01

    Crown fractures are the most common form of traumatic dental injuries encountered in permanent dentition. Restorative treatment modalities incorporate adhesive materials to effectively maintain function and aesthetics. While uncomplicated injuries of the enamel and/or dentin can be treated solely with adhesive procedures, complicated trauma that involves pulp exposure requires the incorporation of a multidisciplinary treatment approach. Fragment reattachment is facilitated by the utilization of bonding agents that enhance retention and aesthetics. This article discusses the application of provisional and permanent restorative options for the treatment of complications following traumatic injuries.

  3. Dental Implants.

    PubMed

    Zohrabian, Vahe M; Sonick, Michael; Hwang, Debby; Abrahams, James J

    2015-10-01

    Dental implants restore function to near normal in partially or completely edentulous patients. A root-form implant is the most frequently used type of dental implant today. The basis for dental implants is osseointegration, in which osteoblasts grow and directly integrate with the surface of titanium posts surgically embedded into the jaw. Radiologic assessment is critical in the preoperative evaluation of the dental implant patient, as the exact height, width, and contour of the alveolar ridge must be determined. Moreover, the precise locations of the maxillary sinuses and mandibular canals, as well as their relationships to the site of implant surgery must be ascertained. As such, radiologists must be familiar with implant design and surgical placement, as well as augmentation procedures utilized in those patients with insufficient bone in the maxilla and mandible to support dental implants.

  4. Dental OCT

    NASA Astrophysics Data System (ADS)

    Wilder-Smith, Petra; Otis, Linda; Zhang, Jun; Chen, Zhongping

    This chapter describes the applications of OCT for imaging in vivo dental and oral tissue. The oral cavity is a diverse environment that includes oral mucosa, gingival tissues, teeth and their supporting structures. Because OCT can image both hard and soft tissues of the oral cavity at high resolution, it offers the unique capacity to identity dental disease before destructive changes have progressed. OCT images depict clinically important anatomical features such as the location of soft tissue attachments, morphological changes in gingival tissue, tooth decay, enamel thickness and decay, as well as the structural integrity of dental restorations. OCT imaging allows for earlier intervention than is possible with current diagnostic modalities.

  5. Assessment of exposures and potential risks to the US adult population from the leaching of elements from gold and ceramic dental restorations.

    PubMed

    Richardson, G Mark; James, Kyle Jordan; Peters, Rachel Elizabeth; Clemow, Scott Richard; Siciliano, Steven Douglas

    2016-01-01

    Using data from the 2001 to 2004 US National Health and Nutrition Examination Survey (NHANES) on the number and placement of tooth restorations in adults, we quantified daily doses due to leaching of elements from gold (Au) alloy and ceramic restorative materials. The elements with the greatest leaching rates from these materials are often the elements of lowest proportional composition. As a result, exposure due to wear will predominate for those elements of relatively high proportional composition, while exposure due leaching may predominate for elements of relatively low proportional composition. The exposure due to leaching of silver (Ag) and palladium (Pd) from Au alloys exceeded published reference exposure levels (RELs) for these elements when multiple full surface crowns were present. Six or more molar crowns would result in exceeding the REL for Ag, whereas three or more crowns would be necessary to exceed the REL for Pd. For platinum (Pt), the majority of tooth surfaces, beyond just molar crowns, would be necessary to exceed the REL for Pd. Exposures due to leaching of elements from ceramic dental materials were less than published RELs for all components examined here, including having all restorations composed of ceramic.

  6. Dental Pulp Defence and Repair Mechanisms in Dental Caries.

    PubMed

    Farges, Jean-Christophe; Alliot-Licht, Brigitte; Renard, Emmanuelle; Ducret, Maxime; Gaudin, Alexis; Smith, Anthony J; Cooper, Paul R

    2015-01-01

    Dental caries is a chronic infectious disease resulting from the penetration of oral bacteria into the enamel and dentin. Microorganisms subsequently trigger inflammatory responses in the dental pulp. These events can lead to pulp healing if the infection is not too severe following the removal of diseased enamel and dentin tissues and clinical restoration of the tooth. However, chronic inflammation often persists in the pulp despite treatment, inducing permanent loss of normal tissue and reducing innate repair capacities. For complete tooth healing the formation of a reactionary/reparative dentin barrier to distance and protect the pulp from infectious agents and restorative materials is required. Clinical and in vitro experimental data clearly indicate that dentin barrier formation only occurs when pulp inflammation and infection are minimised, thus enabling reestablishment of tissue homeostasis and health. Therefore, promoting the resolution of pulp inflammation may provide a valuable therapeutic opportunity to ensure the sustainability of dental treatments. This paper focusses on key cellular and molecular mechanisms involved in pulp responses to bacteria and in the pulpal transition between caries-induced inflammation and dentinogenic-based repair. We report, using selected examples, different strategies potentially used by odontoblasts and specialized immune cells to combat dentin-invading bacteria in vivo.

  7. Dental Pulp Defence and Repair Mechanisms in Dental Caries

    PubMed Central

    Farges, Jean-Christophe; Alliot-Licht, Brigitte; Renard, Emmanuelle; Ducret, Maxime; Gaudin, Alexis; Smith, Anthony J.; Cooper, Paul R.

    2015-01-01

    Dental caries is a chronic infectious disease resulting from the penetration of oral bacteria into the enamel and dentin. Microorganisms subsequently trigger inflammatory responses in the dental pulp. These events can lead to pulp healing if the infection is not too severe following the removal of diseased enamel and dentin tissues and clinical restoration of the tooth. However, chronic inflammation often persists in the pulp despite treatment, inducing permanent loss of normal tissue and reducing innate repair capacities. For complete tooth healing the formation of a reactionary/reparative dentin barrier to distance and protect the pulp from infectious agents and restorative materials is required. Clinical and in vitro experimental data clearly indicate that dentin barrier formation only occurs when pulp inflammation and infection are minimised, thus enabling reestablishment of tissue homeostasis and health. Therefore, promoting the resolution of pulp inflammation may provide a valuable therapeutic opportunity to ensure the sustainability of dental treatments. This paper focusses on key cellular and molecular mechanisms involved in pulp responses to bacteria and in the pulpal transition between caries-induced inflammation and dentinogenic-based repair. We report, using selected examples, different strategies potentially used by odontoblasts and specialized immune cells to combat dentin-invading bacteria in vivo. PMID:26538821

  8. Restoration of Anterior Dental Erosion with a Combination of Veneers and Crowns: A 3-Year Case Report.

    PubMed

    Abreu, Amara; Rucker, M Bryan; Loza, María A; Brackett, William W

    2015-12-01

    This report describes the conservative management of a 40-year-old female patient with smooth, eroded facial enamel affecting her maxillary anterior and some posterior teeth. Using conventional enamel bonding, pressed leucite-reinforced laminate veneers were used to restore the length, contour, and esthetics of the maxillary right canine, as well as of the right lateral and both central incisors; at the same time, it was necessary to restore the maxillary left lateral incisor, canine, and first premolar of the same quadrant with all-ceramic crowns of the same material. The patient has been followed for 3 years and demonstrates a good esthetic outcome with no shade discrepancy between the two types of restoration. Apparently, the tooth structure, though eroded, was able to provide an adequate bonding substrate for these adhesive restorations.

  9. Restoration of Anterior Dental Erosion with a Combination of Veneers and Crowns: A 3-Year Case Report.

    PubMed

    Abreu, Amara; Rucker, M Bryan; Loza, María A; Brackett, William W

    2015-12-01

    This report describes the conservative management of a 40-year-old female patient with smooth, eroded facial enamel affecting her maxillary anterior and some posterior teeth. Using conventional enamel bonding, pressed leucite-reinforced laminate veneers were used to restore the length, contour, and esthetics of the maxillary right canine, as well as of the right lateral and both central incisors; at the same time, it was necessary to restore the maxillary left lateral incisor, canine, and first premolar of the same quadrant with all-ceramic crowns of the same material. The patient has been followed for 3 years and demonstrates a good esthetic outcome with no shade discrepancy between the two types of restoration. Apparently, the tooth structure, though eroded, was able to provide an adequate bonding substrate for these adhesive restorations. PMID:26602583

  10. Application of color image processing and low-coherent optical computer tomography in evaluation of adhesive interfaces of dental restorations

    NASA Astrophysics Data System (ADS)

    Bessudnova, Nadezda O.; Shlyapnikova, Olga A.; Venig, Sergey B.; Genina, Elina A.; Sadovnikov, Alexandr V.

    2015-03-01

    Durability of bonded interfaces between dentin and a polymer material in resin-based composite restorations remains a clinical dentistry challenge. In the present study the evolution of bonded interfaces in biological active environment is estimated in vivo. A novel in vivo method of visual diagnostics that involves digital processing of color images of composite restorations and allows the evaluation of adhesive interface quality over time, has been developed and tested on a group of volunteers. However, the application of the method is limited to the analysis of superficial adhesive interfaces. Low-coherent optical computer tomography (OCT) has been tested as a powerful non-invasive tool for in vivo, in situ clinical diagnostics of adhesive interfaces over time. In the long-term perspective adhesive interface monitoring using standard methods of clinical diagnostics along with colour image analysis and OCT could make it possible to objectivise and prognosticate the clinical longevity of composite resin-based restorations with adhesive interfaces.

  11. A novel closed-loop electromechanical stimulator to enhance osseointegration with immediate loading of dental implant restorations.

    PubMed

    Meswania, I M; Bousdras, V A; Ahir, S P; Cunningham, J L; Blunn, G W; Goodship, A E

    2010-10-01

    The degree of osseomechanical integration of dental implants is acutely sensitive to their mechanical environment. Bone, both as a tissue and structure, adapts its mass and architecture in response to loading conditions. Therefore, application of predefined controlled loads may be considered as a treatment option to promote early maturation of bone/implant interface prior to or in conjunction with crown/prosthesis attachment. Although many studies have established that the magnitude, rate of the applied strain, and frequency have significant effects on the osteogenic response, the actual specific relationships between strain parameters and frequency have not yet been fully defined. The purpose of this study was to develop a stimulator to apply defined mechanical stimuli to individual dental implants in vivo immediately after implantation, exploring the hypothesis that immediate controlled loading could enhance implant integration. An electromechanical device was developed, based on load values obtained using a two-dimensional finite element analysis of the bone/implant interface generating 1000 to 4000 pe and operated at 30 and 3 Hz respectively. The device was then tested in a cadaveric pig mandible, and periosteal bone surface strains were recorded for potential future comparison with a three-dimensional finite element model to determine loading regimens to optimize interface strains and iterate the device for clinical use.

  12. Restorative Treatment Thresholds for Occlusal Primary Caries by Dentists in “The Dental Practice-Based Research Network”

    PubMed Central

    Gordan, Valeria V; Bader, James D; Garvan, Cynthia W; Richman, Joshua S; Qvist, Vibeke; Fellows, Jeffrey L; Rindal, D. Brad; Gilbert, Gregg H

    2010-01-01

    Objectives (1) Quantify at which carious lesion depths dentists intervene surgically for cases of varying caries penetration and caries risk; (2) Identify characteristics that are associated with surgical intervention. Methods Dentists in a practice-based research network who reported doing at least some restorative dentistry were surveyed. Dentists were asked to indicate whether they would surgically intervene in a series of cases depicting occlusal caries. Each case included a photograph of an occlusal surface displaying typical characteristics of caries penetration, and a written description of a patient at a specific level of caries risk. Using logistic regression, we analyzed associations of surgical treatment with dentist and practice characteristics, and patient caries risk levels. Results 519 DPBRN practitioner-investigators responded, of whom 63% indicated that they would surgically restore lesions located on inner enamel surfaces, and 90% of lesions located in outer dentin surfaces in a low caries risk individual. Regarding individuals at high caries risk, 77% reported that they would surgically restore inner enamel lesions and 94% reported restoring lesions located on the outer dentin surface. Dentists who did not assess caries risk were more likely to intervene on dentin lesions (p=.004). Practitioner-investigators who were in private practice were significantly more likely to intervene surgically on enamel lesions, compared to dentists from large group practices (p<.001). Conclusion Most dentists chose to provide some treatment to lesions that were within the enamel surface. Decisions to intervene surgically in the caries process differ by caries lesion depth, patient caries risk, assessment of caries risk, type of practice model, and percent of patients who self-pay. PMID:20123876

  13. Outcomes of root canal treatment in Dental PBRN practices

    PubMed Central

    Gilbert, Gregg H.; Tilashalski, Ken R.; Litaker, Mark S.; McNeal, Sandre F.; Boykin, Michael J.; Kessler, Allen W.

    2010-01-01

    Our purpose was to quantify the incidence of root canal treatment (RCT) failure and identify its predictors in root canals done in or referred from general dentistry practices in a practice-based research network (PBRN). A retrospective cohort study of 174 endodontically-treated teeth was conducted. Mean duration of follow-up was 8.6 years. Permanent restorations were ultimately placed in 89% of teeth; mean (S.D.) number of days to permanent restoration was 215.4 (609.1). Although RCT had been completed, 18% of teeth were ultimately extracted anyway. Receipt of a permanent restoration was a significant predictor of treatment failure, whether it was determined clinically or radiographically. This study of PBRN practices suggests a higher failure rate than reported from studies in highly-controlled environments or populations with high levels of dental insurance. Also, the probability of receipt of a permanent restoration is not optimal -- and strongly predicts RCT failure. Appropriately, no RCT was done on teeth with severe periodontal bone loss. PMID:20129890

  14. Synergistic effects of H2O2 with components of dental restorative materials on gluconeogenesis in rat kidney tubules.

    PubMed

    Franz-Xaver, Reichl; Jürgen, Durner; Kai, Kehe; Matthias, Folwaczny; Norbert, Kleinsasser; Markus, Schwarz; El-Mahdy, Karim; Reinhard, Hickel

    2003-05-01

    No data are available about (toxic) effects of dental materials administered in combination with H(2)O(2) from dental bleaching compounds. The effect of dental composite components triethyleneglycoldimethacrylate (TEGDMA) and hydroxyethylmethacrylate (HEMA) as well as mercuric chloride (HgCl(2)) and methylmercury chloride (MeHgCl), each in combination with H(2)O(2), was investigated on gluconeogenesis in kidney cells. From rats kidney tubules were prepared. Every 10 min up to 60 min 1-ml samples were drawn from the cell suspension for quantitating the glucose content. Glucose formation in controls was 3.5+/-0.3 nmol/mg.per min (mean+/-SEM, n=21). Relative rates of glucose formation were obtained by expressing individual rates as percentage of the corresponding control. X-Y concentration curves (effective concentration, EC) of the substances were calculated by fitting a four-parametric sigmoid function to the relative rates of the glucose formation at various test concentrations. At the end of the incubation period cell viability was assessed by trypan blue exclusion. Cell viability decreased within the 60 min interval from 90% to approx. 80% (controls), <25 (HEMA), <20 (TEGDMA), <20 (H(2)O(2)) <10 (MeHgCl), and <10 (HgCl(2)). Values of 50% effective concentration (EC(50)) were calculated from fitted curves. EC(50) values were (mmol/l; mean+/-SEM; n=4): HEMA, 17.2+/-2.8; TEGDMA, 1.9+/-0.2; H(2)O(2) 0.22+/-0.03, MeHgCl, 0.016+/-0.0005; and HgCl(2), 0.0017+/-0.0005. No significant decrease of the EC(50) values was found when kidney cells were exposed to HEMA, HgCl(2), or MeHgCl in addition with H(2)O(2) (1-100 microM), compared to those EC(50) values of each compound without H(2)O(2) addition. A significant decrease of the TEGDMA EC(50) values to about 0.25 or 0.04 (mmol/l) was found when cells were exposed to TEGDMA in combination with H(2)O(2) (75 or 100 microM), compared to that TEGDMA EC(50) value without H(2)O(2) addition. The addition of H(2)O(2) (75 and 100

  15. Predictors of dental rehabilitation in children aged 3–12 years

    PubMed Central

    Gopinath, Vellore Kannan; Awad, Manal A.

    2015-01-01

    Objectives: The aim of this study was to evaluate the proportion of completed treatments and to study the factors affecting the full mouth dental rehabilitation in pediatric patients treated by undergraduate students at the College of Dental Medicine Teaching Clinics, University of Sharjah. Materials and Methods: A retrospective study was conducted on 270 children aged less than 12 years (mean age 7.6, SD 2.04). Comprehensive dental rehabilitation reports of child patients that were completed by final year dental undergraduate students from the year 2009 to 2011 were reviewed. Data on complete history, oral examination, dental charting, and treatment plan were collected from pediatric dentistry case sheet. Dental caries was charted using WHO 1997 criteria. Dental treatment needs and completion of dental care delivered to children involved in this study were assessed using DMFT/deft scores. Results: Percentages of treatment provided included completed restorations (94%) and space management (84%) in primary dentition, whereas 98% of restoration and 94% of required sealants were completed in permanent dentition. The percentage of completed dental treatment including sealant placement was 61%. Age of the child and the number of decayed teeth present before the start of the treatment significantly correlated with the children in the incomplete treatment category (P < 0.05). Conclusions: Therefore, a worthy dental care was provided in a holistic approach to the children attending College of Dental Medicine training clinics. Age of the child and the number of decayed teeth were the factors affecting dental rehabilitation in children aged 3–12 years. PMID:26236683

  16. Objective assessment of the influence of the parental presence on the fear and behavior of anxious children during their first restorative dental visit

    PubMed Central

    Pani, Sharat C.; AlAnazi, Ghazi S.; AlBaragash, Abdulrahman; AlMosaihel, Mohammad

    2016-01-01

    Aims and Objectives: Parents play an important role in the dental behavior of a child patient. This study aimed to assess the effect of parental presence on the behavior of the child and objectively measure the behavior using pulse oximetry. Materials and Methods: The study was registered with the clinical trials registry of the National Institutes of Health (NCT02619981). The children were divided into three groups, those who had no accompanying parent, those accompanied by their fathers, and those accompanied by their mothers. The Venham anxiety and behavior scores were used for subjective measurements whereas the objective measurement of fear was done by measuring the heart rate using a portable pulse oximeter at six critical clinical situations. Statistical analysis was carried out using the Statistical Package for the Social Sciences version 21 (IBM corp. Armonk, NY, USA). Results: One hundred and twenty two children aged between 6 years and 8 years completed the study. Most of the children accompanied by fathers were males while most of the children accompanied by their mother were females. It was seen that females showed a higher mean heart rate than males at all steps. Children who had their parents outside the operatory exhibited lower anxiety and behavior scores than those whose parents were present; however, they showed a significantly higher pulse rate at all procedures. Boys had higher anxiety and behavior scores than girls, however, these differences were not statistically significant. Conclusion: The results of this study suggest that the presence of the parent in the operatory reduces the physiological manifestations of anxiety in children in their first restorative dental visit.

  17. Objective assessment of the influence of the parental presence on the fear and behavior of anxious children during their first restorative dental visit

    PubMed Central

    Pani, Sharat C.; AlAnazi, Ghazi S.; AlBaragash, Abdulrahman; AlMosaihel, Mohammad

    2016-01-01

    Aims and Objectives: Parents play an important role in the dental behavior of a child patient. This study aimed to assess the effect of parental presence on the behavior of the child and objectively measure the behavior using pulse oximetry. Materials and Methods: The study was registered with the clinical trials registry of the National Institutes of Health (NCT02619981). The children were divided into three groups, those who had no accompanying parent, those accompanied by their fathers, and those accompanied by their mothers. The Venham anxiety and behavior scores were used for subjective measurements whereas the objective measurement of fear was done by measuring the heart rate using a portable pulse oximeter at six critical clinical situations. Statistical analysis was carried out using the Statistical Package for the Social Sciences version 21 (IBM corp. Armonk, NY, USA). Results: One hundred and twenty two children aged between 6 years and 8 years completed the study. Most of the children accompanied by fathers were males while most of the children accompanied by their mother were females. It was seen that females showed a higher mean heart rate than males at all steps. Children who had their parents outside the operatory exhibited lower anxiety and behavior scores than those whose parents were present; however, they showed a significantly higher pulse rate at all procedures. Boys had higher anxiety and behavior scores than girls, however, these differences were not statistically significant. Conclusion: The results of this study suggest that the presence of the parent in the operatory reduces the physiological manifestations of anxiety in children in their first restorative dental visit. PMID:27652248

  18. Cleidocranial Dysplasia Case Report: Remodeling of Teeth as Aesthetic Restorative Treatment

    PubMed Central

    da Cunha, Leonardo Fernandes; Caetano, Isabela Maria; Dalitz, Fernando; Gonzaga, Carla Castiglia; Mondelli, José

    2014-01-01

    Cleidocranial dysplasia (CCD), is an autosomal dominant disorder with a prevalence of 1 in 1,000,000 individuals. It is generally characterized by orofacial manifestations, including enamel hypoplasia, retained primary teeth, and impacted permanent and supernumerary teeth. The successful treatment involving a timing intervention (orthodontic-maxillofacial surgeons-restorative) is already described. However, the restorative treatment might improve the aesthetic final result in dentistry management for patients with cleidocranial dysplasia. Objective. Therefore, this clinical report presents a conservative restorative management (enamel microabrasion, dental bleaching, and direct composite resin) for aesthetic solution for a patient with CCD. Clinical Considerations. The cosmetic remodeling is a conservative, secure, and low cost therapy that can be associated with other procedures such as enamel microabrasion and dental bleaching to achieve optimal outcome. Additionally, the Golden Proportion can be used to guide dental remodeling to improve the harmony of the smile and the facial composition. Conclusions. Thus, dentists must know and be able to treat dental aesthetic problems in cleidocranial dysplasia patients. The intention of this paper is to describe a restorative approach with the cosmetic remodeling teeth (by grinding or addicting material) associated with enamel microabrasion and dental bleaching to reestablish the form, shape, and color of smile for patients with cleidocranial dysplasia. PMID:25045546

  19. Dental material artifacts on MR images.

    PubMed

    Hinshaw, D B; Holshouser, B A; Engstrom, H I; Tjan, A H; Christiansen, E L; Catelli, W F

    1988-03-01

    Magnetic resonance (MR) imaging of the head and neck is becoming an important aid in evaluating pathologic conditions of the brain, midface, and pharynx. Certain dental materials cause artifacts during MR imaging of the lower midface. These artifacts can obscure the normal anatomy. This study describes the degree of artifact production caused by various materials commonly used in dental restorations. Of the materials tested, those causing artifacts were made of stainless steel, such as orthodontic bands used for braces, and pins or posts that are commonly drilled into teeth to provide structure or stability before filling. Materials used as temporary or permanent fillings or crowns--such as amalgam, gold alloy, aluminum, microfilled resin, and polyvinyl acrylics--did not cause artifacts in the images.

  20. Enamel hypoplasia: challenges of esthetic restorative treatment.

    PubMed

    Ruschel, Vanessa Carla; Araújo, Élito; Bernardon, Jussara Karina; Lopes, Guilherme Carpena

    2016-01-01

    Enamel defects, such as white or yellow-brown spots, usually cause problems that are more esthetic than functional. Enamel hypoplasia may be the result of hereditary, systemic, or local factors. Dental trauma is a local etiologic factor. It is relatively common in the primary dentition and can cause defects on the surface of permanent successors. Treatment for such defects can differ, depending on the depth of the spots. For deeper white-spot lesions, a composite resin restoration may be necessary. This is an excellent mode of treatment, due to both its low cost and its conservation of healthy tooth structure. The objective of this case report is to describe composite resin restoration of a maxillary central incisor affected by enamel hypoplasia.

  1. Enamel hypoplasia: challenges of esthetic restorative treatment.

    PubMed

    Ruschel, Vanessa Carla; Araújo, Élito; Bernardon, Jussara Karina; Lopes, Guilherme Carpena

    2016-01-01

    Enamel defects, such as white or yellow-brown spots, usually cause problems that are more esthetic than functional. Enamel hypoplasia may be the result of hereditary, systemic, or local factors. Dental trauma is a local etiologic factor. It is relatively common in the primary dentition and can cause defects on the surface of permanent successors. Treatment for such defects can differ, depending on the depth of the spots. For deeper white-spot lesions, a composite resin restoration may be necessary. This is an excellent mode of treatment, due to both its low cost and its conservation of healthy tooth structure. The objective of this case report is to describe composite resin restoration of a maxillary central incisor affected by enamel hypoplasia. PMID:27599287

  2. Erosive potential of commonly used beverages, medicated syrup, and their effects on dental enamel with and without restoration: An in vitro study

    PubMed Central

    Trivedi, Krishna; Bhaskar, Vijay; Ganesh, Mahadevan; Venkataraghavan, Karthik; Choudhary, Prashant; Shah, Shalin; Krishnan, Ramesh

    2015-01-01

    Aim: This study evaluates erosive potential of commonly used beverages, medicated syrup, and their effects on dental enamel with and without restoration in vitro. Materials and Methods: Test medias used in this study included carbonated beverage, noncarbonated beverage, high-energy sports drink medicated cough syrup, distilled water as the control. A total of 110 previously extracted human premolar teeth were selected for the study. Teeth were randomly divided into two groups. Test specimens were randomly distributed to five beverages groups and comprised 12 specimens per group. Surface roughness (profilometer) readings were performed at baseline and again, following immersion for 14 days (24 h/day). Microleakage was evaluated. The results obtained were analyzed for statistical significance using SPSS-PC package using the multiple factor ANOVA at a significance level of P < 0.05. Paired t-test, Friedman test ranks, and Wilcoxon signed ranks test. Results: For surface roughness high-energy sports drink and noncarbonated beverage showed the highly significant difference with P values of 0.000 and 0.000, respectively compared to other test media. For microleakage high-energy sports drink had significant difference in comparison to noncarbonated beverage (P = 0.002), medicated syrup (P = 0.000), and distilled water (P = 0.000). Conclusion: High-energy sports drink showed highest surface roughness value and microleakage score among all test media and thus greater erosive potential to enamel while medicated syrup showed least surface roughness value and microleakage among all test media. PMID:26538901

  3. RADIOPACITY OF RESTORATIVE MATERIALS USING DIGITAL IMAGES

    PubMed Central

    Salzedas, Leda Maria Pescinini; Louzada, Mário Jefferson Quirino; de Oliveira, Antonio Braz

    2006-01-01

    The radiopacity of esthetic restorative materials has been established as an important requirement, improving the radiographic diagnosis. The aim of this study was to evaluate the radiopacity of six restorative materials using a direct digital image system, comparing them to the dental tissues (enamel-dentin), expressed as equivalent thickness of aluminum (millimeters of aluminum). Five specimens of each material were made. Three 2-mm thick longitudinal sections were cut from an intact extracted permanent molar tooth (including enamel and dentin). An aluminum step wedge with 9 steps was used. The samples of different materials were placed on a phosphor plate together with a tooth section, aluminum step wedge and metal code letter, and were exposed using a dental x-ray unit. Five measurements of radiographic density were obtained from each image of each item assessed (restorative material, enamel, dentin, each step of the aluminum step wedge) and the mean of these values was calculated. Radiopacity values were subsequently calculated as equivalents of aluminum thickness. Analysis of variance (ANOVA) indicated significant differences in radiopacity values among the materials (P<0.0001). The radiopacity values of the restorative materials evaluated were, in decreasing order: TPH, F2000, Synergy, Prisma Flow, Degufill, Luxat. Only Luxat had significantly lower radiopacity values than dentin. One material (Degufill) had similar radiopacity values to enamel and four (TPH, F2000, Synergy and Prisma Flow) had significantly higher radiopacity values than enamel. In conclusion, to assess the adequacy of posterior composite restorations it is important that the restorative material to be used has enough radiopacity, in order to be easily distinguished from the tooth structure in the radiographic image. Knowledge on the radiopacity of different materials helps professionals to select the most suitable material, along with other properties such as biocompatibility, adhesion and

  4. Critical appraisal: dental amalgam update--part II: biological effects.

    PubMed

    Wahl, Michael J; Swift, Edward J

    2013-12-01

    Dental amalgam restorations have been controversial for over 150 years. In Part I of this Critical Appraisal, the clinical efficacy of dental amalgam was updated. Here in Part II, the biological effects of dental amalgam are addressed.

  5. Restoring the worn dentition.

    PubMed

    Ibsen, R L; Ouellet, D F

    1992-01-01

    Strong dental materials and dental porcelains are providing dentists with restorative opportunities that are more conservative because they require less destruction of healthy tooth structure and yield a more esthetic result. In cases of severe wear due to attrition, abrasion, and erosion, this process can be stopped, restoring the esthetics and function by using proper techniques and materials. The case report described in this article demonstrates the conservative restoration of severe wear due to attrition and erosion. Teeth were lengthened, wear was restored, and further wear was ceased by using a combination of bonded porcelain, a heat, light, and self-cure resin system, and a new glass-ionomer restorative material. The result was a strong, durable restoration (that required no anesthesia) with high esthetics.

  6. 21 CFR 872.3700 - Dental mercury.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Dental mercury. 872.3700 Section 872.3700 Food and... DENTAL DEVICES Prosthetic Devices § 872.3700 Dental mercury. (a) Identification. Dental mercury is a device composed of mercury intended for use as a component of amalgam alloy in the restoration of...

  7. Use of a compact fiber optic spectrometer for spectral feedback during the laser ablation of dental hard tissues and restorative materials

    NASA Astrophysics Data System (ADS)

    Cheng, Joyce Y.; Fan, Kenneth; Fried, Daniel

    2006-02-01

    One perceived disadvantage of caries removal using lasers is the loss of the tactile feedback associated with the handpiece. However, alternative methods of acoustic and optical feedback become available with the laser that can be exploited to provide information about the chemical composition of the material ablated, the ablation efficiency and rate, the depth of the incision, and the surface and plume temperature during ablation. Such information can be used to increase the selectivity of ablation, avoid peripheral thermal damage and excessive heat deposition in the tooth, and provide a mechanism of robotic automation. The objective of this study was to test the hypothesis that a compact fiberoptic spectrometer could be used to differentiate between the ablation of sound and carious enamel and dentin and between dental hard tissues and composite. Sound and carious tooth surfaces along with composite restorative materials were scanned with λ=0.355, 2.79 and 9.3 μm laser pulses at irradiation intensities ranging from 0.5-100 J/cm2 and spectra were acquired from λ=250-900-nm using a compact fiber-optic spectrometer. Emission spectra varied markedly with the laser wavelength and pulse duration. Optical feedback was not successful in differentiating between sound and carious enamel and dentin even with the addition of various chromophores to carious lesion areas. However, the spectral feedback was successfully used to differentiate between composites and sound enamel and dentin enabling the selective removal of composite from tooth surfaces using a computer controlled λ=9.3-μm pulsed CO II laser and scanning system.

  8. Restoration of ankle movements with the ActiGait implantable drop foot stimulator: a safe and reliable treatment option for permanent central leg palsy.

    PubMed

    Martin, Klaus Daniel; Polanski, Witold Henryk; Schulz, Anne-Kathrin; Jöbges, Michael; Hoff, Hansjoerg; Schackert, Gabriele; Pinzer, Thomas; Sobottka, Stephan B

    2016-01-01

    OBJECT The ActiGait drop foot stimulator is a promising technique for restoration of lost ankle function by an implantable hybrid stimulation system. It allows ankle dorsiflexion by active peroneal nerve stimulation during the swing phase of gait. In this paper the authors report the outcome of the first prospective study on a large number of patients with stroke-related drop foot. METHODS Twenty-seven patients who experienced a stroke and with persisting spastic leg paresis received an implantable ActiGait drop foot stimulator for restoration of ankle movement after successful surface test stimulation. After 3 to 5 weeks, the stimulator was activated, and gait speed, gait endurance, and activation time of the system were evaluated and compared with preoperative gait tests. In addition, patient satisfaction was assessed using a questionnaire. RESULTS Postoperative gait speed significantly improved from 33.9 seconds per 20 meters to 17.9 seconds per 20 meters (p < 0.0001), gait endurance from 196 meters in 6 minutes to 401 meters in 6 minutes (p < 0.0001), and activation time from 20.5 seconds to 10.6 seconds on average (p < 0.0001). In 2 patients with nerve injury, surgical repositioning of the electrode cuff became necessary. One patient showed a delayed wound healing, and in another patient the system had to be removed because of a wound infection. Marked improvement in mobility, social participation, and quality of life was confirmed by 89% to 96% of patients. CONCLUSIONS The ActiGait implantable drop foot stimulator improves gait speed, endurance, and quality of life in patients with stroke-related drop foot. Regarding gait speed, the ActiGait system appears to be advantageous compared with foot orthosis or surface stimulation devices. Randomized trials with more patients and longer observation periods are needed to prove the long-term benefit of this device.

  9. 12 CFR 1229.11 - Capital restoration plans.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... capital restoration plan submitted by a Bank shall set forth a plan to restore its permanent and total... restoration plan, including setting forth a schedule for it to restore its permanent and total capital to... submission. A Bank must submit a proposed capital restoration plan no later than 15 business-days after...

  10. Treatment of "non-restorable" teeth. A case report.

    PubMed

    Donly, K J

    1991-08-01

    The purpose of this article is to present a case report of the dental care for permanent teeth that were originally considered "non-restorable". The temporary placement of stainless steel crowns was completed, followed by traditional endodontic therapy. The crowns were used as build-up matrices, access being prepared in the occlusal of the crown. Glass ionomer silver was then placed, followed by marginal finishing. Although this report is an isolated case, and is considered as temporary treatment, there may be indications to consider this technique for clinical care, on an individual basis.

  11. Combined amalgam and composite restorations.

    PubMed

    Abu-Hanna, Amer A; Mjör, Ivar A

    2004-01-01

    All indirect restorative techniques involving cast metals, ceramics or resin-based materials are expensive compared to directly placed restorations. A restorative technique is presented that combines the esthetic properties of directly bonded resin-based composite material and the wide range of indications for dental amalgam in stress-bearing areas.

  12. Oral Health-Related Quality of Life and Traumatic Dental Injuries in Young Permanent Incisors in Brazilian Schoolchildren: A Multilevel Approach

    PubMed Central

    2015-01-01

    Background Traumatic dental injury (TDI) during childhood may negatively impact the quality of life of children. Objective To describe the association of oral health-related quality of life (OHRQoL) and domains (oral symptons, functional limitation, emotional- and social-well-being) of children with individual and contextual variables. Methods A cross-sectional study was performed using a representative sample of 1,201 schoolchildren, 8–10 years-old, from public and private schools of Belo Horizonte, Brazil. The CPQ8–10 was used to assess OHRQoL, dichotomized in low and high impact. Sociodemographic information was collected through questionnaires to parents. Children were examined at schools, using the Andreasen criteria. Individual variables were gender, age, number of residents in home, parents/caregivers’ level of education, family income, and TDI (dichotomized into without trauma/mild trauma and severe trauma). Dental caries and malocclusion were considered co-variables. Contextual variables were the Social Vulnerability Index and type of school. Ethical approval and consent forms were obtained. Data were analyzed using SPSS for Windows 19.0 and HLM 6.06, including frequency distribution, chi-squared test and multilevel approach (p < 0.05). Results The prevalence of a negative impact on OHRQoL in children with severe trauma was 55.9%. The TDI negatively impacted emotional and social domains of OHRQoL. A multilevel analysis revealed a significant difference in OHRQoL according to the type of school and showed that 16% of the total variance was due to contextual characteristics (p < 0.001; ICC = 0.16). The negative impact on OHRQoL was higher in girls (p = 0.009), younger children (p = 0.023), with severe TDI (p = 0.014), those from public schools (p = 0.017) and whose parents had a lower education level (p = 0.001). Conclusion Severe trauma impacts OHRQoL on emotional and social domains. Contextual dimensions add information to individual variability to

  13. Dental Amalgam

    MedlinePlus

    ... Products and Medical Procedures Dental Devices Dental Amalgam Dental Amalgam Share Tweet Linkedin Pin it More sharing options Linkedin Pin it Email Print Dental amalgam is a dental filling material which is ...

  14. Reparative dentistry or restorative dentistry?

    PubMed

    Small, Bruce W

    2008-01-01

    The real definition of restorative dentistry is found in the heart and hands of each individual restorative dentist. His or her training, continuing dental education, mentors, needs (financial and emotional), and style of practice all help to develop a philosophy of dental practice that affects daily restorative decisions. Depending on the factors described above, the decision to repair a tooth or change the environment and restore the tooth to a different shape, size, or color also may change. In recent years, patients' esthetic desires have become more of a factor than they were in previous decades. There are no exact written-tn-stone definitions of restorative dentistry, since the answers are operator-dependent and can vary. This column is meant to be food for thought and perhaps inspire discussion when dentists assemble for meetings or study clubs with the goal of delivering longer-lasting dentistry through a restorative dental practice. PMID:18348367

  15. The atraumatic restorative treatment (ART) strategy in Mexico: two-years follow up of ART sealants and restorations

    PubMed Central

    2013-01-01

    Background The massive use of preventive measures in Mexico has resulted in a large decline in dental caries over the past two decades. There does however remain a largely unmet need for restorative treatment. This paper describes the steps leading up to the adoption of a strategy, as part of general health policy, to use Atraumatic Restorative Treatment (ART) within the Mexican public health service as a means of addressing this. The objective was to evaluate ART restorations and sealants placed in primary and permanent teeth in schoolchildren from deprived areas over a period of 2 years. Methods 18 Dentists from 13 municipalities in 6 states with the lowest human development index treated 304, 6- to 13-year-old schoolchildren with ART sealants and ART restorations (single-surfaces) on the school compounds. Ketac Molar Easymix was the filling material used. ART procedures were evaluated according to the ART assessment criteria after 1 and 2 years, by 7 calibrated evaluators. Survival rates were estimated, using the PHREG Model with frailty correction. Results The 2-year cumulative survival rates of fully and partially retained ART sealants were 73.1% (primary teeth) and 48.8% (permanent teeth). The dentine carious lesion failure rates of ART sealants in primary and permanent teeth over the 2-year period were 0% and 2.5%, respectively. The 2-year cumulative survival rates of single-surface ART restorations in primary and permanent teeth were 74% and 80.9%, respectively. Secondary carious lesion development occurred in 6 restored primary teeth (2.1%) and in one restored permanent tooth (1.3%). All restorations placed in primary teeth in one state survived, whilst those in one of the 5 remaining states failed statistically significantly more than those in the other 4. Conclusions The ART procedures were of substantial quality and had prevented to a large extent the development of new dentine carious lesions in these children from socio-economically deprived areas

  16. Laboratory-made composite resin restorations in children and adolescents with hypoplasia or hypomineralization of teeth.

    PubMed

    Feierabend, Stefanie; Halbleib, Karl; Klaiber, Bernd; Hellwig, Elmar

    2012-04-01

    Management of children and adolescents with qualitative or quantitative defects of enamel or dentin are often impeded by patient compliance, rare prevalence of disease, lack of evidence, and cost. The aim for all patients in this case series was to develop a suitable treatment strategy that required little chair time and was applicable to several conditions. Thirty-four laboratory-made composite resin restorations were placed in differently affected permanent posterior teeth of eight young patients. The ages of the patients ranged from 6 to 15 years. All restorations were adhesively inserted with the etch-and-rinse technique and are still in situ. The longevity of the restorations at present is 2 to 48 months. This treatment method allowed relatively comfortable treatment for children and adolescents who required extensive dental treatment. The outcome has been favorable with good patient compliance, brief chair time, and functional and esthetic restorations.

  17. New nano-sized Al2O3-BN coating 3Y-TZP ceramic composites for CAD/CAM-produced all-ceramic dental restorations. Part I. Fabrication of powders.

    PubMed

    Yang, Se Fei; Yang, Li Qiang; Jin, Zhi Hao; Guo, Tian Wen; Wang, Lei; Liu, Hong Chen

    2009-06-01

    Partially sintered 3 mol % yttria-stabilized tetragonal zirconium dioxide (ZrO(2), zirconia) polycrystal (3Y-TZP) ceramics are used in dental posterior restorations with computer-aided design-computer-aided manufacturing (CAD/CAM) techniques. High strength is acquired after sintering, but shape distortion of preshaped compacts during their sintering is inevitable. The aim of this study is to fabricate new machinable ceramic composites with strong mechanical properties that are fit for all-ceramic dental restorations. Aluminum oxide (Al(2)O(3))-coated 3Y-TZP powders were first prepared by the heterogeneous precipitation method starting with 3Y-TZP, Al(NO(3))(3) . 9H(2)O, and ammonia, then amorphous boron nitride (BN) was produced and the as-received composite powders were coated via in situ reaction with boric acid and urea. Transmission electron microscopy (TEM) and X-ray diffraction (XRD) were used to analyze the status of Al(2)O(3)-BN on the surface of the 3Y-TZP particles. TEM micrographs show an abundance of Al(2)O(3) particles and amorphous BN appearing uniformly on the surface of the 3Y-TZP particles after the coating process. The size of the Al(2)O(3) particles is about 20 nm. The XRD pattern shows clearly the peak of amorphous BN among the peaks of ZrO(2). PMID:19223246

  18. The restorative management of microdontia.

    PubMed

    Laverty, D P; Thomas, M B M

    2016-08-26

    Microdontia is a dental abnormality that will often present to the dental practitioner due to the aesthetic concerns of the patient. Treatment is therefore aimed at addressing the aesthetics issue of the patient and this can present a number of challenges which may require a multidisciplinary approach in its management. This article presents the restorative management of localised and generalised microdontia. PMID:27561572

  19. Dental amalgam: An update

    PubMed Central

    Bharti, Ramesh; Wadhwani, Kulvinder Kaur; Tikku, Aseem Prakash; Chandra, Anil

    2010-01-01

    Dental amalgam has served as an excellent and versatile restorative material for many years, despite periods of controversy. The authors review its history, summarize the evidence with regard to its performance and offer predictions for the future of this material. The PubMed database was used initially; the reference list for dental amalgam featured 8641 articles and 13 publications dealing with recent advances in dental amalgam. A forward search was undertaken on selected articles and using some author names. For the present, amalgam should remain the material of choice for economic direct restoration of posterior teeth. When esthetic concerns are paramount, tooth-colored materials, placed meticulously, can provide an acceptable alternative. All alternative restorative materials and procedures, however, have certain limitations. PMID:21217947

  20. Mercury toxicity and dental amalgam

    SciTech Connect

    Wolff, M.; Osborne, J.W.; Hanson, A.L.

    1982-01-01

    There is adequate evidence that dental amalgam restorations, during and after placement, results in the release of Hg into the patients's body. Whether the Hg released from amalgam is due to placement procedures, surface abrasion, or later corrosion breakdown, there is evidence that a low level Hg release continues for years. With new and more accurate techniques of measuring Hg levels, especially in tissue and blood, additional studies are necessary to relate blood-Hg levels with dental amalgam restorations. Studies must relate existing restorations as well as the placement of new restorations to body-Hg levels. It is possible that we have accepted a potentially dangerous material as being safe.

  1. Preventing dental caries in children: Indian scenario.

    PubMed

    Gupta, A; Marya, C M; Dahiya, V; Bhatia, H P; Dhingra, S

    2012-01-01

    The prevalence of dental caries in developing countries like India is increasing to an alarming level in contrast to developed countries where it has decreased because of variety of preventive measures at the community and individual level. There is no State or Centre funded programs for prevention of dental diseases in India. The present review enlists the targeted prevention of dental caries in permanent teeth of 6 to 16 years old children presenting for dental care.

  2. Dental amalgam: A review of the literature

    SciTech Connect

    Eggleston, D.W.

    1989-09-01

    Since the 1800s, dental amalgam has been the most commonly used dental restorative material. Each year, dentistry in the United States uses over 100 tons of mercury, continuing a controversy regarding mercury's safety for patients and dental personnel. 65 references.

  3. 78 FR 24761 - National Institute of Dental & Craniofacial Research; Notice of Closed Meetings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-26

    ... HUMAN SERVICES National Institutes of Health National Institute of Dental & Craniofacial Research... personal privacy. Name of Committee: National Institute of Dental and Craniofacial Research Special Emphasis Panel; Design and Development of Novel Dental Composite Restorative Systems Review Panel....

  4. The quality of impressions for crowns and bridges: an assessment of the work received at three commercial dental laboratories. assessing qualities of impressions that may lead to occlusal discrepancies with indirect restorations.

    PubMed

    Storey, D; Coward, T J

    2014-03-01

    There are few published studies that directly assess the quality of impressions for crowns and bridges in the UK. This paper considers aspects of impression quality with particular attention to factors causing potential occlusal discrepancies in the final restoration. To this end three dental laboratories were visited over a 3-month period. All impressions for conventional crown and bridgework that arrived on the days of the visits were examined and assessed against criteria defined on a custom-designed assessment form. A total of 206 impression cases were considered in this study. Flexible impression trays were used for 65% of working impressions. Their use was more common for NHS work than for private work. 31.9% of all alginate impressions examined were not adequately fixed to the tray. Visible contamination of impressions was not uncommon.

  5. Class II Resin Composites: Restorative Options.

    PubMed

    Patel, Minesh; Mehta, Shamir B; Banerji, Subir

    2015-10-01

    Tooth-coloured, resin composite restorations are amongst the most frequently prescribed forms of dental restoration to manage defects in posterior teeth. The attainment of a desirable outcome when placing posterior resin composite restorations requires the clinician to have a good understanding of the benefits (as well as the limitations) posed by this material, together with a sound knowledge of placement technique. Numerous protocols and materials have evolved to assist the dental operator with this type of demanding posterior restoration. With the use of case examples, four techniques available are reported here. CPD/Clinical Relevance: This article explores varying techniques for the restoration of Class II cavities using resin composite.

  6. [Influence of implant restoration on traditional restoration idea].

    PubMed

    Liu, H C

    2016-01-01

    Implant restoration affected the traditional restoration idea. Artificial implant restoration has a profound influence on the design of dental restoration. Implant supported prostheses have not only changed the method of oral rehabilitation, but also integrated revolutionary concept with the traditional treatment protocol. By using implants, posterior missing molars can be effectively restored and thus eliminating the disadvantages of traditional removable partial denture for Kennedy classification Ⅰ, Ⅱ partically edentulous dentition. Full edentulous arch can also be restored with implant fixed denture which provide much better oral health related quality of life compared with the traditional complete denture. It is useful to master the theory and skills of artificial implant restoration, and to provide a reference for the restoration of oral physiological function.

  7. Quantitative determination of TEGDMA, BHT, and DMABEE in eluates from polymerized resin-based dental restorative materials by use of GC/MS.

    PubMed

    Seiss, Mario; Langer, Christopher; Hickel, Reinhard; Reichl, Franz-Xaver

    2009-12-01

    This study investigated the leaching of ingredients from several commercial dental composite resins cured with LED, and immersed in methanol or water for 24 h, respectively. The composites used were: Admira Dentin (VOCO), Artemis Schmelz (Enamel) (Ivoclar Vivadent), Els extra low shrinkage (Saremco Dental), Filtek Supreme XT Dentin (3 M ESPE), Gradia Direct (GC), Venus & Venus flow (Heraeus Kulzer), and XRV Herculite Prodigy Enamel (Kerr). From each dental composite four specimens with defined structure and 100-mg net weight were made. After the polymerization process, according to manufacturer's instructions, the specimens were immersed in either 1 ml water or 1 ml methanol and incubated at 37 degrees C for 24 h. Eluted ingredients triethyleneglycoldimethacrylate (TEGDMA), 2,6-di-tert-butyl-4-methylphenol (BHT), and 4-N,N-dimethylaminobenzoicacidethylester (DMABEE) were detected and quantified using gas chromatography-mass spectrometry (GC-MS). The amounts of the detected analytes from 100 mg polymerized composites ranged between the following values: TEGDMA: 0-0.5 mg (water), 0-1.6 mg (methanol); BHT: 0-0.03 μg (water), 0-0.11 mg (methanol); and DMABEE: 0-0.11 mg (water), 0-1.4 mg (methanol). We conclude from the results that the elution rates into methanol and water differ significantly. Furthermore, it is concluded that all the determined amounts eluting from the composites are far below toxic-relevant concentrations. PMID:19771414

  8. Minimal intervention dentistry: part 5. Atraumatic restorative treatment (ART)--a minimum intervention and minimally invasive approach for the management of dental caries.

    PubMed

    Holmgren, C J; Roux, D; Doméjean, S

    2013-01-01

    While originally developed in response to a need to provide effective restorative and preventive treatment in underserved communities where running water and electricity might not always be available, over the past two decades, the atraumatic restorative treatment (ART) approach has become a worldwide phenomenon; used not only in some of the poorest developing countries but also in some of the most wealthy. The ART approach involves the removal of infected dentine with hand-instruments followed by the placement of a restoration where the adjacent pits and fissures are sealed simultaneously using high viscosity glass-ionomer inserted under finger pressure. Reliable results can only be obtained if the treatment protocol, as described in this article, is closely followed. ART should be considered as a therapeutic option especially in children, anxious patients and those with special needs.

  9. [The application of universal adhesives in dental bonding].

    PubMed

    Guo, Jingmei; Lei, Wenlong; Yang, Hongye; Huang, Cui

    2016-03-01

    The bonding restoration has become an important clinical technique for the development of dental bonding technology. Because of its easy operation and the maximum preservation of tooth tissues, bonding repair is widely used in dental restoration. The recent multi-mode universal adhesives have brought new progress in dental bonding restoration. In this article the universal adhesives were reviewed according to its definition, development, improvement, application features and possible problems.

  10. Surface texture measurement for dental wear applications

    NASA Astrophysics Data System (ADS)

    Austin, R. S.; Mullen, F.; Bartlett, D. W.

    2015-06-01

    The application of surface topography measurement and characterization within dental materials science is highly active and rapidly developing, in line with many modern industries. Surface measurement and structuring is used extensively within oral and dental science to optimize the optical, tribological and biological performance of natural and biomimetic dental materials. Although there has historically been little standardization in the use and reporting of surface metrology instrumentation and software, the dental industry is beginning to adopt modern areal measurement and characterization techniques, especially as the dental industry is increasingly adopting digital impressioning techniques in order to leverage CAD/CAM technologies for the design and construction of dental restorations. As dental treatment becomes increasingly digitized and reliant on advanced technologies such as dental implants, wider adoption of standardized surface topography and characterization techniques will become evermore essential. The dental research community welcomes the advances that are being made in surface topography measurement science towards realizing this ultimate goal.

  11. Dental Sealants

    MedlinePlus

    ... Data & Statistics > Find Data by Topic > Dental Sealants Dental Sealants Main Content Dental sealants are thin plastic coatings that protect the chewing surfaces of children’s back teeth from tooth decay. Overall, the prevalence of sealants ...

  12. Dental care demand among children with dental insurance.

    PubMed Central

    Grembowski, D; Conrad, D A; Milgrom, P

    1987-01-01

    As the number of families with dental insurance and expenditures for dental care has increased over the past two decades, so has interest in determining cost-sharing effects on dental demand among insureds. Using a representative sample of Pennsylvania Blue Shield children insureds during 1980, we estimate cost-sharing effects on dental demand for basic (diagnostic, preventive, restorative, endodontic, and extraction services) and orthodontic care. Results indicate that cost-sharing has little influence on the probability of using any dental services and basic expenditures. However, the probability of using orthodontic services decreases 2.1 percent when the proportion of orthodontic expenditures paid by the parent increases 10 percent. By reducing the cost of care, cost-sharing reduces social class differences in dental demand common in unisured populations, likely producing public oral health benefits. PMID:2952622

  13. Dental therapists in general dental practices: an economic evaluation.

    PubMed

    Beazoglou, Tryfon J; Lazar, Vickie F; Guay, Albert H; Heffley, Dennis R; Bailit, Howard L

    2012-08-01

    Dental access disparities are well documented and have been recognized as a national problem. Their major cause is the lack of reasonable Medicaid reimbursement rates for the underserved. Specifically, Medicaid reimbursement rates for children average 40 percent below market rates. In addition, most state Medicaid programs do not cover adults. To address these issues, advocates of better oral health for the underserved are considering support for a new allied provider--a dental therapist--capable of providing services at a lower cost per service and in low-income and rural areas. Using a standard economic analysis, this study estimated the potential cost, price, utilization, and dentist's income effects of dental therapists employed in general dental practices. The analysis is based on national general dental practice data and the broadest scope of responsibility for dental therapists that their advocates have advanced, including the ability to provide restorations and extractions to adults and children, training for three years, and minimum supervision. Assuming dental therapists provide restorative, extraction, and pulpal services to patients of all ages and dental hygienists continue to deliver all hygiene services, the mean reduction in a general practice costs ranges between 1.57 and 2.36 percent. For dental therapists treating children only, the range is 0.31 to 0.47 percent. The effects on price and utilization are even smaller. In addition, the effects on most dentists' gross income, hours of work, and net income are negative. The estimated economic impact of dental therapists in the United States on private dental practice is very limited; therefore, the demand for dental therapists by private practices also would probably be very limited.

  14. Stainless steel crown bridge replacing permanent molar in the adolescent patient: a case report.

    PubMed

    Dimri, M; Jain, A

    2001-06-01

    The loss of a permanent molar in young adolescent patient creates a need for early space maintenance and restoration of function. To establish function and esthetics short-term treatments include interim restorative approaches. This paper describes a functional, cost-effective stainless steel crown bridge as an interim restoration after the loss of permanent first molar in an early adolescent dentition.

  15. Dental Procedures.

    PubMed

    Ramponi, Denise R

    2016-01-01

    Dental problems are a common complaint in emergency departments in the United States. There are a wide variety of dental issues addressed in emergency department visits such as dental caries, loose teeth, dental trauma, gingival infections, and dry socket syndrome. Review of the most common dental blocks and dental procedures will allow the practitioner the opportunity to make the patient more comfortable and reduce the amount of analgesia the patient will need upon discharge. Familiarity with the dental equipment, tooth, and mouth anatomy will help prepare the practitioner for to perform these dental procedures. PMID:27482994

  16. Novel Osteogenic Ti-6Al-4V Device For Restoration Of Dental Function In Patients With Large Bone Deficiencies: Design, Development And Implementation

    PubMed Central

    Cohen, D. J.; Cheng, A.; Kahn, A.; Aviram, M.; Whitehead, A. J.; Hyzy, S. L.; Clohessy, R. M.; Boyan, B. D.; Schwartz, Z.

    2016-01-01

    Custom devices supporting bone regeneration and implant placement are needed for edentulous patients with large mandibular deficiencies where endosteal implantation is not possible. We developed a novel subperiosteal titanium-aluminum-vanadium bone onlay device produced by additive manufacturing (AM) and post-fabrication osteogenic micro-/nano-scale surface texture modification. Human osteoblasts produced osteogenic and angiogenic factors when grown on laser-sintered nano-/micro-textured surfaces compared to smooth surfaces. Surface-processed constructs caused higher bone-to-implant contact, vertical bone growth into disk pores (microCT and histomorphometry), and mechanical pull-out force at 5 and 10 w on rat calvaria compared to non surface-modified constructs, even when pre-treating the bone to stimulate osteogenesis. Surface-modified wrap-implants placed around rabbit tibias osseointegrated by 6 w. Finally, patient-specific constructs designed to support dental implants produced via AM and surface-processing were implanted on edentulous mandibular bone. 3 and 8 month post-operative images showed new bone formation and osseointegration of the device and indicated stability of the dental implants. PMID:26854193

  17. Proper selection of contemporary dental cements.

    PubMed

    Yu, Hao; Zheng, Ming; Chen, Run; Cheng, Hui

    2014-03-01

    Today proper selection of dental cements is a key factor to achieve a successful restoration and will greatly increase the chances of long-term success of the restoration. In recent years, many newly formulated dental cements have been developed with the claim of better performance compared to the traditional materials. Unfortunately, selection of suitable dental cement for a specific clinical application has become increasingly complicated, even for the most experienced dentists. The purpose of this article is to review the currently existing dental cements and to help the dentists choose the most suitable materials for clinical applications.

  18. Essure Permanent Birth Control

    MedlinePlus

    ... Implants and Prosthetics Essure Permanent Birth Control Essure Permanent Birth Control Share Tweet Linkedin Pin it More sharing options ... evaluation of the Essure System Essure is a permanent birth control method for women (female sterilization). Implantation of Essure ...

  19. Full-mouth oral rehabilitation in a titanium allergy patient using zirconium oxide dental implants and zirconium oxide restorations. A case report from an ongoing clinical study.

    PubMed

    Oliva, Xavi; Oliva, Josep; Oliva, Josep D

    2010-01-01

    This case report describes the full-mouth oral rehabilitation of a titanium allergic patient. The patient was a young female with amelogenesis imperfecta who had generalized massive tooth destruction. All teeth in the mouth were extracted and 15 CeraRoot acid-etched (ICE surface) implants were placed (seven implants in the maxilla and eight implants in the mandible). No immediate temporaries were placed. Temporaries were placed 3 months after surgery, and left in function for 2 months. The case was finally restored with zirconium oxide bridges and ceramic veneering (three bridges in the maxilla and another three in the mandible). The 3-year follow-up showed good stability of soft tissues and bone level. Zirconium oxide implants and restorations might be an alternative for the oral rehabilitation of titanium allergic patients.

  20. An in vitro Evaluation of Microleakage of Posterior Teeth Restored with Amalgam, Composite and Zirconomer – A Stereomicroscopic Study

    PubMed Central

    Punia, Sandhya Kapoor; Bhat, Surekha; Singh, Gautam; Goyal, Pravesh; Oza, Swapnil; Raiyani, Chirag M.

    2015-01-01

    Background Numerous restorative materials are being used in dentistry to achieve adequate strength and restore aesthetics. However, a perfect ideal restorative material has still eluded dentist. Dental amalgam is versatile material with self-sealing property, but is unaesthetic. Other restorative materials like, composites require conservative preparation, but exhibits polymerisation shrinkage resulting in microleakage. To overcome these drawbacks a high strength restorative material reinforced with ceramic and zirconia fillers known as zirconomer has been introduced. The aim of this study was to evaluate the micro-leakage of these three different restorative materials. Materials and Methods Thirty non-carious human permanent first and second molars were utilized in this study. Class I cavities were prepared on the occlusal surface; cavities were then restored with amalgam, composite and zirconomer as per manufacture’s instruction. All samples were stored for 24 hours in distilled water followed by thermocycling. The entire tooth surface was painted with two coats of varnish to within 1mm of the restoration margins. The teeth were immersed in dye. Teeth were sectioned and observed under stereomicroscope. Results In this study the zirconomer exhibited the highest micro leakage as compared to composite and amalgam but composite having higher micro leakage as compared to amalgam and lower micro leakage as compared to zirconomer. Conclusion Even though composite and amalgam are being marketed aggressively and new material like zirconomer are on origin, amalgam still proves to be one of the best materials. PMID:26393208

  1. Treatment planning for restorative implantology.

    PubMed

    Boyce, Ricardo A; Klemons, Gary

    2015-04-01

    In this article, current literature on fixed and removable prosthodontics is reviewed along with evidence-based systematic reviews, including advice from those in the dental profession with years of experience, which help restorative dentists manage and treat their cases successfully. Treatment planning for restorative implantology should be looked at in 4 sections: (1) review of past medical history, (2) oral examination and occlusion, (3) dental imaging (ie, cone-beam computed tomography), and (4) fixed versus removable prosthodontics. These 4 concepts of treatment planning, along with proper surgical placements of the implant(s), result in successful cases. PMID:25835794

  2. Treatment planning for restorative implantology.

    PubMed

    Boyce, Ricardo A; Klemons, Gary

    2015-04-01

    In this article, current literature on fixed and removable prosthodontics is reviewed along with evidence-based systematic reviews, including advice from those in the dental profession with years of experience, which help restorative dentists manage and treat their cases successfully. Treatment planning for restorative implantology should be looked at in 4 sections: (1) review of past medical history, (2) oral examination and occlusion, (3) dental imaging (ie, cone-beam computed tomography), and (4) fixed versus removable prosthodontics. These 4 concepts of treatment planning, along with proper surgical placements of the implant(s), result in successful cases.

  3. Tricho-Dento-Osseous Syndrome: Diagnosis and Dental Management

    PubMed Central

    Al-Batayneh, Ola B.

    2012-01-01

    Tricho-dento-osseous (TDO) syndrome is a rare, autosomal dominant disorder principally characterised by curly hair at infancy, severe enamel hypomineralization and hypoplasia and taurodontism of teeth, sclerotic bone, and other defects. Diagnostic criteria are based on the generalized enamel defects, severe taurodontism especially of the mandibular first permanent molars, an autosomal dominant mode of inheritance, and at least one of the other features (i.e., nail defects, bone sclerosis, and curly, kinky or wavy hair present at a young age that may straighten out later). Confusion with amelogenesis imperfecta is common; however, taurodontism is not a constant feature of any of the types of amelogenesis imperfecta. Management of TDO requires a team approach, proper documentation, and a long-term treatment and follow-up plan. The aim of treatment is to prevent problems such as sensitivity, caries, dental abscesses, and loss of occlusal vertical dimension through attrition of hypoplastic tooth structure. Another aim is to restore function of the dentition and enhance the esthetics and self-esteem of the patient. This paper proposes treatment approaches that include preventive, restorative, endodontic, prosthetic, and surgical options to management. In addition, it sheds light on the difficulties faced during dental treatment of such cases. PMID:22969805

  4. [Functional dental anatomy and amalgam].

    PubMed

    Tavernier, B; Colon, P

    1989-01-01

    Very often, the functional dental anatomy are reflected during the rehabilitation of posterior quadrants. However, the placement, the shaping in correct relation of the different dental components are indispensable conditions to respect, in order to achieve an adequate integration of the restoration within the neuro-muscular system. A clinical protocol is proposed in order to reconcile the anatomical and biological prerequisite and the setting time of modern alloys.

  5. 49 CFR 192.717 - Transmission lines: Permanent field repair of leaks.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... encirclement welded split sleeve of appropriate design, unless the transmission line is joined by mechanical... method that reliable engineering tests and analyses show can permanently restore the serviceability...

  6. Re-eruption of an intruded immature permanent incisor with necrotic pulp: a case report.

    PubMed

    Altun, Ceyhan; Güven, Günseli; Cehreli, Zafer C; Gurbuz, Taskin; Aydin, Cumhur

    2008-01-01

    Intrusive luxation is a serious dental injury that causes damage to the pulp and supporting structures of a tooth because of its dislocation into the alveolar process. This paper presents the case of the re-eruption of a severely intruded immature permanent incisor with a crown-root fracture. A 9-year-old boy was referred to the clinic 1 day after a fall. Clinical and radiographic examinations revealed intrusive luxation of the immature left permanent incisor and a crown-root fracture without pulp exposure. Palatal gingivectomy was done 2 weeks later to facilitate re-eruption. Root canal therapy with intracanal calcium hydroxide paste was initiated during the first month owing to severe spontaneous pain. Six months later, the tooth re-erupted to a normal position, after which root canal obturation and a final esthetic restoration were done. The present case demonstrates the possibility of obtaining re-eruption of intruded immature permanent teeth with interim medication (calcium hydroxide) in the root canal.

  7. Immediate Placement and Occlusal Loading of Single-Tooth Restorations on Partially Threaded, Titanium-Tantalum Combined Dental Implants: 1-Year Results.

    PubMed

    Peron, Cristian; Romanos, Georgios

    2016-01-01

    Single nonrestorable teeth were atraumatically extracted and hybrid titanium implants with tantalum-based midsections (TM) were placed in fresh extraction sockets. Provisional acrylic crowns were delivered (in occlusion) immediately after surgery. Occlusal contacts were present in the maximal intercuspation but not in the lateral movements of the mandible. Two weeks after placement, the implants were finally restored with screw-retained or cemented lithium disilicate crowns. A total of 25 patients were treated (26 implants). Most implants were placed in maxillary premolar locations and in lower-density bone. Mean crestal bone loss was 0.58 ± 0.34 mm. Implant survival and success rates were 100%, respectively (follow-up: 14.1 ± 1.5 months). Within the limitations of this study, immediate placement and loading of TM implants resulted in predictable clinical, functional, and esthetic outcomes.

  8. Immediate Placement and Occlusal Loading of Single-Tooth Restorations on Partially Threaded, Titanium-Tantalum Combined Dental Implants: 1-Year Results.

    PubMed

    Peron, Cristian; Romanos, Georgios

    2016-01-01

    Single nonrestorable teeth were atraumatically extracted and hybrid titanium implants with tantalum-based midsections (TM) were placed in fresh extraction sockets. Provisional acrylic crowns were delivered (in occlusion) immediately after surgery. Occlusal contacts were present in the maximal intercuspation but not in the lateral movements of the mandible. Two weeks after placement, the implants were finally restored with screw-retained or cemented lithium disilicate crowns. A total of 25 patients were treated (26 implants). Most implants were placed in maxillary premolar locations and in lower-density bone. Mean crestal bone loss was 0.58 ± 0.34 mm. Implant survival and success rates were 100%, respectively (follow-up: 14.1 ± 1.5 months). Within the limitations of this study, immediate placement and loading of TM implants resulted in predictable clinical, functional, and esthetic outcomes. PMID:27100809

  9. To Analyse the Erosive Potential of Commercially Available Drinks on Dental Enamel and Various Tooth Coloured Restorative Materials – An In-vitro Study

    PubMed Central

    Jindal, Ritu; Mahajan, Sandeep; Sandhu, Sanam; Sharma, Sunila; Kaur, Rajwinder

    2016-01-01

    Introduction With the enormous change in life style pattern of a common man through the past few decades, there has been proportional variation in the amount and frequency of consumption of drinks. An increased consumption of these drinks will concurrently increase enamel surface roughness by demineralization, resulting in hypersensitivity and elevated caries risk. Aim The present study was designed to evaluate the erosive potential of commercially available drinks on tooth enamel and various tooth coloured restorative materials. Materials and Methods Extracted human teeth were taken and divided into four groups i.e. tooth enamel, glass ionomer cement, composite and compomer. Four commercially available drinks were chosen these were Coca -Cola, Nimbooz, Frooti and Yakult. The pH of each drink was measured. Each group was immersed in various experimental drinks for a period of 14 days. The erosive potential of each drink was measured by calculating the change in average surface roughness of these groups after the immersion protocol in various drinks. The data analysis was done by One Way Anova, Post-Hoc Bonferroni, and paired t –test. Results Group II-GIC showed highest values for mean of change in average surface roughness and the values were statistically significant (p<0.001) with tooth enamel, composite and compomer (p=0.002). Coca-cola showed the highest erosive potential and Yakult showed the lowest, there was no statistical significant difference between the results shown by Yakult and Frooti. Conclusion Characteristics which may promote erosion of enamel and tooth coloured restorative materials were surface texture of the material and pH of the drinks. PMID:27437343

  10. Coinsurance effects on dental prices.

    PubMed

    Grembowski, D; Conrad, D A

    1986-01-01

    For many Americans the cost of dental services represents a barrier to receiving regular dental care and maintaining proper oral health. The recent growth of the dental insurance industry, however, may partly offset this price barrier among insureds. Our purpose is to examine the relationship between coinsurance and dental prices for 16 dental services among a sample of Pennsylvania Blue Shield (PBS) adult insureds. The dependent price measure is the annual average gross price paid for 16 specific preventive, restorative, periodontic, endodontic, prosthodontic, and surgical dental services. Independent variables in the price model include the insured's age, education, coinsurance rates, time costs, market area, non-wage income, oral health status, area dentist-population ratio and usual source of care. Data sources are 1980 PBS claims and coinsurance rate data and a mail survey of sampled insureds. OLS regression analysis reveals that the model's independent variables explain little dental price variation. No variable is consistently significant across services, but market area, coinsurance rates, and time costs alternately dominate across equations. These results suggest that, among adult insureds, coinsurance and time costs influence dental fees in a minority of dental services. Insurance reduces the patient's sensitivity to money price, and non-price factors correspondingly seem to become more important in patient search.

  11. Achieving functional restorations utilizing a new Ceromer system.

    PubMed

    Trinkner, T

    1997-01-01

    The advent of pressed ceramic restorations (IPS Empress, Ivoclar Williams, Amherst, NY) has driven dental therapy to continuously strive for more aesthetic and functional materials. The dental profession requires restorations to exhibit strength, natural color, wear resistance, marginal integrity, and ease of fabrication in the restorative therapies selected. With the introduction of a new ceromer and fiber-reinforced composite (FRC) system (Targis System, Ivoclar Williams, Amherst, NY), the replacement of a single tooth or multiple teeth with a FRC, metal-free bridge is now a suitable alternative to conventional dental therapy. This presentation will review the clinical protocol, material properties, and aesthetic characteristics of this new generation of restorative material.

  12. Hardening behavior after high-temperature solution treatment of Ag-20Pd-12Au-xCu alloys with different Cu contents for dental prosthetic restorations.

    PubMed

    Kim, Yonghwan; Niinomi, Mitsuo; Hieda, Junko; Nakai, Masaaki; Cho, Ken; Fukui, Hisao

    2014-07-01

    Ag-Pd-Au-Cu alloys have been used widely for dental prosthetic applications. Significant enhancement of the mechanical properties of the Ag-20Pd-12Au-14.5Cu alloy as a result of the precipitation of the β' phase through high-temperature solution treatment (ST), which is different from conventional aging treatment in these alloys, has been reported. The relationship between the unique hardening behavior and precipitation of the β' phase in Ag-20Pd-12Au-xCu alloys (x=6.5, 13, 14.5, 17, and 20mass%) subjected to the high-temperature ST at 1123K for 3.6ks was investigated in this study. Unique hardening behavior after the high-temperature ST also occurs in Ag-20Pd-12Au-xCu alloys (x=13, 17, and 20) with precipitation of the β' phase. However, hardening is not observed and the β' phase does not precipitate in the Ag-20Pd-12Au-6.5Cu alloy after the same ST. The tensile strength and 0.2% proof stress also increase in Ag-20Pd-12Au-xCu alloys (x=13, 14.5, 17, and 20) after the high-temperature ST. In addition, these values after the high-temperature ST increase with increasing Cu content in Ag-20Pd-12Au-xCu alloys (x=14.5, 17, and 20). The formation process of the β' phase can be explained in terms of diffusion of Ag and Cu atoms and precipitation of the β' phase. Clarification of the relationship between hardening and precipitation of the β' phase via high-temperature ST is expected to help the development of more effective heat treatments for hardening in Ag-20Pd-12Au-xCu alloys.

  13. The Chemistry of Modern Dental Filling Materials.

    ERIC Educational Resources Information Center

    Nicholson, John W.; Anstice, H. Mary

    1999-01-01

    Discusses materials used by dentists to restore teeth after decay has been removed. Shows how dental-material science is an interdisciplinary field in which chemistry plays a major part. Reviews the many developments polymer chemistry has contributed to the field of dental fillings. (CCM)

  14. FATIGUE OF DENTAL CERAMICS

    PubMed Central

    Zhang, Yu; Sailer, Irena; Lawn, Brian R

    2013-01-01

    Objectives Clinical data on survival rates reveal that all-ceramic dental prostheses are susceptible to fracture from repetitive occlusal loading. The objective of this review is to examine the underlying mechanisms of fatigue in current and future dental ceramics. Data/sources The nature of various fatigue modes is elucidated using fracture test data on ceramic layer specimens from the dental and biomechanics literature. Conclusions Failure modes can change over a lifetime, depending on restoration geometry, loading conditions and material properties. Modes that operate in single-cycle loading may be dominated by alternative modes in multi-cycle loading. While post-mortem examination of failed prostheses can determine the sources of certain fractures, the evolution of these fractures en route to failure remains poorly understood. Whereas it is commonly held that loss of load-bearing capacity of dental ceramics in repetitive loading is attributable to chemically-assisted 'slow crack growth' in the presence of water, we demonstrate the existence of more deleterious fatigue mechanisms, mechanical rather than chemical in nature. Neglecting to account for mechanical fatigue can lead to gross overestimates in predicted survival rates. Clinical significance Strategies for prolonging the clinical lifetimes of ceramic restorations are proposed based on a crack-containment philosophy. PMID:24135295

  15. 12 CFR 1229.11 - Capital restoration plans.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 7 2011-01-01 2011-01-01 false Capital restoration plans. 1229.11 Section 1229... PROMPT CORRECTIVE ACTION Federal Home Loan Banks § 1229.11 Capital restoration plans. (a) Contents. Each capital restoration plan submitted by a Bank shall set forth a plan to restore its permanent and...

  16. 12 CFR 1229.11 - Capital restoration plans.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 7 2010-01-01 2010-01-01 false Capital restoration plans. 1229.11 Section 1229... PROMPT CORRECTIVE ACTION Federal Home Loan Banks § 1229.11 Capital restoration plans. (a) Contents. Each capital restoration plan submitted by a Bank shall set forth a plan to restore its permanent and...

  17. Creating esthetic composite restorations.

    PubMed

    Grin, D

    2000-05-01

    The purpose of this article is to describe a fabrication technique to assist dental technicians creating esthetic indirect composite restorations. After the teeth have been prepared and the models completed, the technician can begin the fabrication process. Translucent dentin is selected to reduce opacity and enhance the blend with the remaining dentition. High chroma modifiers can then be placed into the fossa area to replicate dentin seen in natural dentition. Different incisal materials can then be layered into the build-up to regulate the value of the restoration. Special effects such as hypocalcification are placed internally to mimic naturally occurring esthetics. Realistic anatomy is created using a small-tipped instrument directly into the final layer of uncured enamel material. Fissure characterization is placed in the restoration to match existing dentition. Fit and margins are verified on separate dies to minimize discrepancies. Path of insertion and proximal contacts are established on a solid model to minimize chairside adjustments.

  18. Human enamel veneer restoration: an alternative technique to restore anterior primary teeth.

    PubMed

    Oliveira, Luciana Butini; Tamay, Tereza Keiko; Oliveira, Marta Dutra Machado; Rodrigues, Célia Martins Delgado; Wanderley, Marcia Turolla

    2006-01-01

    Restoration of severely decayed primary teeth is a clinical challenge in Pediatric Dentistry. Among the restorative treatment options, the use of prefabricated crowns and resin composite restorations, either by means of direct or indirect techniques is mentioned in the literature. The purpose of this article is to describe the rehabilitation of primary anterior teeth in a 5-year-old patient. Dental treatment consisted on an anterior space maintainer prosthesis made with natural primary teeth, plus human dental enamel veneer (facet) restorations. The advantages of this technique are better esthetics and the natural enamel has physiologic wear and offers superficial smoothness and cervical adaptation compatible with those of the surrounding teeth.

  19. Human enamel veneer restoration: an alternative technique to restore anterior primary teeth.

    PubMed

    Oliveira, Luciana Butini; Tamay, Tereza Keiko; Oliveira, Marta Dutra Machado; Rodrigues, Célia Martins Delgado; Wanderley, Marcia Turolla

    2006-01-01

    Restoration of severely decayed primary teeth is a clinical challenge in Pediatric Dentistry. Among the restorative treatment options, the use of prefabricated crowns and resin composite restorations, either by means of direct or indirect techniques is mentioned in the literature. The purpose of this article is to describe the rehabilitation of primary anterior teeth in a 5-year-old patient. Dental treatment consisted on an anterior space maintainer prosthesis made with natural primary teeth, plus human dental enamel veneer (facet) restorations. The advantages of this technique are better esthetics and the natural enamel has physiologic wear and offers superficial smoothness and cervical adaptation compatible with those of the surrounding teeth. PMID:16937849

  20. Effects of various chair-side surface treatment methods on dental restorative materials with respect to contact angles and surface roughness.

    PubMed

    Sturz, Candida R C; Faber, Franz-Josef; Scheer, Martin; Rothamel, Daniel; Neugebauer, Jörg

    2015-01-01

    Available chair-side surface treatment methods may adversely affect prosthetic materials and promote plaque accumulation. This study investigated the effects of treatment procedures on three resin restorative materials, zirconium-dioxide and polyetheretherketone in terms of surface roughness and hydrophobicity. Treatments were grinding with silicon carbide paper or white Arkansas stone, blasting with prophylaxis powder and polishing with diamond paste. Surface roughness was assessed using confocal laser scanning. Hydrophobicity as measured by water contact angle was determined by computerized image analysis using the sessile drop technique. All of the specific surface treatments performed led to significant changes in contact angle values and surface roughness (Ra) values. Median contact angle values ranged from 51.6° to 114°. Ra values ranged from 0.008 µm to 2.917 µm. Air-polishing as well as other polishing procedures increased surface roughness values in all materials except zirconium dioxide. Polyetheretherketone displayed greatest change in contact angle values after air-polishing treatment. PMID:26632228

  1. Dental Hygienists

    MedlinePlus

    ... anatomy, patient management, and periodontics, which is the study of gum disease. High school students interested in becoming dental hygienists should take courses in biology, chemistry, and math. Most dental hygiene programs also require applicants to have completed at ...

  2. Dental sealants

    MedlinePlus

    ... this page: //medlineplus.gov/ency/patientinstructions/000779.htm Dental sealants To use the sharing features on this ... case a sealant needs to be replaced. How Dental Sealants Are Applied Your dentist applies sealants on ...

  3. Epidermolysis bullosa: dental and anesthetic management of two cases.

    PubMed

    Wright, J T

    1984-02-01

    Epidermolysis bullosa (EB) is a group of rare genetic disorders which are of dental interest because of their specific oral manifestations and management difficulties. Two cases of recessive EB which may be classified clinically as the atrophicans-gravis Herlitz type are described. Dental therapy consisted of extractions and stainless steel crown restorations, with inhalation general anesthesia. The need for and advantages of early preventive and restorative dental care are illustrated by the cases presented.

  4. Biological restorations using tooth fragments.

    PubMed

    Busato, A L; Loguercio, A D; Barbosa, A N; Sanseverino, M do C; Macedo, R P; Baldissera, R A

    1998-02-01

    A "biological" restoration technique using dental fragments and adhesive materials is described. These fragments were obtained from extracted human teeth which had been previously sterilized and stored in a tooth bank. The advantages are: the use of extracted teeth as restorative material, esthetics, and treatment cost. The positive sensation of having back the missing tooth was the most mentioned comment among patients. The disadvantages are: the difficulty of obtaining teeth with the needed characteristics, problems of making an indirect restoration, matching the original color, and the non-acceptance by some patients who consider it strange to have other people's teeth placed in their mouths.

  5. Recent trends in esthetic restorations for posterior teeth.

    PubMed

    Dietschi, D; Magne, P; Holz, J

    1994-10-01

    The increase in the demands made by patients for esthetic or metal-free restorations, together with the ever-growing interest shown by the dental profession for tooth-colored materials and techniques, led to the current development of posterior adhesive restorations. This paper reviews critical elements such as adhesion to dental hard tissues as well as current properties of bases/liners, filling materials, and luting materials. A rationale for the successful use of currently available restorative systems is presented.

  6. Infrared laser irradiation of dental enamel using submicrosecond laser pulses with and without an applied water layer: effect on bond strength to restorative materials

    NASA Astrophysics Data System (ADS)

    Sarma, Anupama V.; Staninec, Michal; Le, Charles Q.; Fried, Daniel

    2004-05-01

    Previous studies have shown that during IR laser irradiation at CO2 and Er:YAG laser wavelengths, residual particles of fused non-apatite calcium phosphate phases accumulate that may inhibit adhesion to restorative materials. A layer of water added to the enamel surface before ablation prevents the accumulation of such phases. The objective of this study was to investigate the influence of laser pulse duration and wavelength with and without the added water layer on the bond strength of composite to laser prepared enamel surfaces. The surfaces of bovine enamel were irradiated by three lasers systems: a 0.5-μs Er:YSGG laser. a 25-μs Er:YAG laser and a 5-μs TEA CO2 laser operating at 9.6-μm. A motion control system and a pressurized spray system incorporating a microprocessor controlled pulsed nozzle for water delivery, were used to ensure uniform treatment of the entire surface. There was no significant reduction in the shear-bond strength of enamel to composite for the shorter erbium laser pulses if a water-spray was not used, in contrast to previous results for the 200-μs free-running Er:YAG laser in which the water-spray resulted in significantly higher bond-strengths. Shear-bond strengths for both erbium laser systems were significantly higher than for the CO2 laser irradiated samples and the negative control (no acid-etch) but significantly lower than the positive control group (phosphoric acid-etch). The application of the water-spray markedly influenced the surface morphology for all three laser systems with the most uniform surface preparation being produced by the 25-μs Er:YAG laser and the 5-μs CO2 laser with the water-spray.

  7. Guidelines for Direct Adhesive Composite Restoration.

    PubMed

    Society Of Cariology And Endodontology, Chinese Stomatological Association Csa

    2015-01-01

    Direct adhesive composite restoration, a technique to restore tooth defects by bonding composite resin materials, has been widely used in the restoration of dental caries or other tooth defects. Retention of composite resin restoration mainly relies on bonding strength between the materials and dental tissue. The clinical outcomes rely greatly on the regulated clinical practice of dentists. In 2011, the Society of Cariology and Endodontology of Chinese Stomatological Association (CSA) published the 'Practices and evaluation criteria of composite resin bonded restoration (Discussion Version)'. Since then, opinions and comments regarding the 'Discussion Version' have been widely circulated within the Society. The final version of the guideline was based on systematic reviews of scientific literature and requirements for the edit of technical guidelines, and through several rounds of discussions, revisions and supplements. The society recommends this guideline for clinicians to use in their practices, when conducting direct composite restorations.

  8. Placement technique for direct posterior composite restorations.

    PubMed

    Javaheri, D S

    2001-04-01

    Due to improved materials, instrumentation, and placement techniques, composite resins have overcome the traditional complications associated with wear resistance, microleakage, sensitivity, and tight anatomical contacts. Composite resins have been utilized with increased frequency for direct posterior restorations capable of satisfying the growing aesthetic expectations of contemporary dental patients. When properly placed, posterior composites can provide successful and predictable restorations. This article presents clinical considerations for the aesthetic conservation of posterior restorations with composite resin materials.

  9. Rare earth permanent magnets

    SciTech Connect

    Major-Sosias, M.A.

    1993-10-01

    Permanent magnets were discovered centuries ago from what was known as {open_quotes}lodestone{close_quotes}, a rock containing large quantities of the iron-bearing mineral magnetite (Fe{sub 3}O{sub 4}). The compass was the first technological use for permanent magnetic materials; it was used extensively for navigational purposes by the fifteenth century. During the twentieth century, as new applications for permanent magnets were developed, interest and research in permanent magnetic materials soared. Four major types of permanent magnets have been developed since the turn of the century.

  10. Dental problems in athletes.

    PubMed

    Inouye, Jill; McGrew, Chris

    2015-01-01

    Orofacial injuries and diseases occur in athletes, and they may not always have access to dentists. Therefore team physicians should be aware of the common injuries and initial management. Treatment of dental injuries will depend on whether the teeth are primary or permanent. The most common type of fracture is crown fracture, but there are other dental injuries that can lead to future complications if not treated promptly and monitored closely. Tooth avulsions need to be handled properly, and athletes should see a dentist as soon as possible. Despite the urgency of some injuries, other orofacial injuries or diseases, such as lacerations and caries, should not be overlooked. Proper education and use of mouth guards can assist athletes in reducing their risk of orofacial injuries. PMID:25574879

  11. Dental composites and amalgam and physical development in children.

    PubMed

    Maserejian, N N; Hauser, R; Tavares, M; Trachtenberg, F L; Shrader, P; McKinlay, S

    2012-11-01

    Resin-based composite dental restoration materials may release bisphenol-A, an endocrine-disrupting chemical. Using secondary analysis of a randomized clinical safety trial of amalgam vs. composites, we tested the hypothesis that dental restoration materials affect children's growth. Children (N = 218 boys, N = 256 girls) aged 6 to 10 yrs at baseline with ≥ 2 decayed posterior teeth were randomized to amalgam or composites (bisphenol-A-diglycidyl-dimethacrylate composite for permanent teeth, urethane-dimethacrylate compomer for primary teeth) for treatment of posterior caries throughout follow-up. Primary outcomes for this analysis were 5-year changes in BMI-for-age z-scores, body fat percentage (BF%), and height velocity; exploratory analyses (n = 113) examined age at menarche. Results showed no significant differences between treatment assignment and changes in physical development in boys [(composites vs. amalgam) BF%, 4.9 vs. 5.7, p = 0.49; (BMI-z-score) 0.13 vs. 0.25, p = 0.36] or girls (8.8 vs. 7.7, p = 0.95; 0.36 vs. 0.21, p = 0.49). Children with more treatment on primary teeth had greater increases in BF% regardless of material type. Girls assigned to composites had lower risk of menarche during follow-up (hazard ratio = 0.57, 95% CI 0.35-0.95). Overall, there were no significant differences in physical development over 5 years in children treated with composites or amalgam. Additional studies examining these restoration materials in relation to age at menarche are warranted (clinicaltrials.gov number NCT00065988).

  12. Dental Composites and Amalgam and Physical Development in Children

    PubMed Central

    Maserejian, N.N.; Hauser, R.; Tavares, M.; Trachtenberg, F.L.; Shrader, P.; McKinlay, S.

    2012-01-01

    Resin-based composite dental restoration materials may release bisphenol-A, an endocrine-disrupting chemical. Using secondary analysis of a randomized clinical safety trial of amalgam vs. composites, we tested the hypothesis that dental restoration materials affect children’s growth. Children (N = 218 boys, N = 256 girls) aged 6 to 10 yrs at baseline with ≥ 2 decayed posterior teeth were randomized to amalgam or composites (bisphenol-A-diglycidyl-dimethacrylate composite for permanent teeth, urethane-dimethacrylate compomer for primary teeth) for treatment of posterior caries throughout follow-up. Primary outcomes for this analysis were 5-year changes in BMI-for-age z-scores, body fat percentage (BF%), and height velocity; exploratory analyses (n = 113) examined age at menarche. Results showed no significant differences between treatment assignment and changes in physical development in boys [(composites vs. amalgam) BF%, 4.9 vs. 5.7, p = 0.49; (BMI-z-score) 0.13 vs. 0.25, p = 0.36] or girls (8.8 vs. 7.7, p = 0.95; 0.36 vs. 0.21, p = 0.49). Children with more treatment on primary teeth had greater increases in BF% regardless of material type. Girls assigned to composites had lower risk of menarche during follow-up (hazard ratio = 0.57, 95% CI 0.35-0.95). Overall, there were no significant differences in physical development over 5 years in children treated with composites or amalgam. Additional studies examining these restoration materials in relation to age at menarche are warranted (clinicaltrials.gov number NCT00065988). PMID:22972857

  13. Head and neck cancer, dental implants, and dental oncology.

    PubMed

    Garg, Arun; Guez, Ghislaine

    2011-01-01

    Head and neck cancer is a real presence in the dental-implant world--patients who undergo surgery, chemotherapy, and/or radiation often seek the assistance of dental-implant practitioners to restore them to better function; other patients who have had implants in place for years will return with questions regarding how their treatment will be affected by the presence of their dental implant. As oral-cancer treatment modalities are rapidly changing, practitioners struggle to keep up with the literature surrounding this important subset of the dental-implant population. This month, we look at the numbers of patients suffering from oral cancers, consider the different treatment options for patients with oral cancers, and investigate the role that implants play in improving therapeutic outcomes or changing treatment course.

  14. Changing trends in hair restoration surgery.

    PubMed

    Venkataram, Mysore

    2006-01-01

    Androgenetic alopecia is an important and common cause for baldness. Despite recent advances, the drug therapy of this condition remains unsatisfactory. Surgical hair restoration is the only permanent method of treating this condition. Introduction of recent techniques such as follicular unit transplantation have improved the cosmetic results and patient satisfaction. This article discusses the latest trends in hair restoration surgery. PMID:16707815

  15. Dental Care for a Child with Cleft Lip and Palate

    MedlinePlus

    ... will need fillings or removal of a tooth. Orthodontic Care The first orthodontic evaluation may be scheduled even before the child ... of the permanent teeth, the final phase of orthodontics completes alignment of the teeth. Coordinated Dental-Surgical ...

  16. Restoring Function and Aesthetics in a Class II Division 1 Patient with Amelogenesis Imperfecta: A Clinical Report

    PubMed Central

    Doruk, Cenk; Ozturk, Firat; Sari, Fatih; Turgut, Mehmet

    2011-01-01

    Amelogenesis imperfecta (AI) encompasses a complicated group of hereditary conditions that cause developmental alterations in the structure of the enamel in the absence of a systemic disorder. AI primarily affects the quality and/or quantity of dental enamel, and it may affect all or only some of the teeth in the primary and/or permanent dentition. This clinical report describes the oral rehabilitation of a 21-year-old man diagnosed with hypomaturation-type AI. He presented with discolored and mutilated teeth. Cephalometrically, the patient has skeletal class II malocclusion due to mandibular deficiency considered as a result of maxillary constriction. The interdisciplinary approach was followed because of the complex needs of the patient. The aim of treatment was to restore aesthetics, improve malocclusion and masticatory function. Aesthetic and functional expectations were met with metal ceramic restorations. In this report, the interdisciplinary approach for a patient with AI and a malocclusion is described. PMID:21494393

  17. Agenesis of multiple primary and permanent teeth unilaterally and its possible management.

    PubMed

    Ephraim, Rena; Rajamani, T; Feroz, Tp Mohammed; Abraham, Sajith

    2015-05-01

    Oligodontia is the agenesis of numerous teeth (more than six teeth). Agenesis of teeth in primary and permanent dentition is a rare incidence and very few are reported in the dental literature. Although the etiology of congenital agenesis of teeth is unclear, several factors such as a tendency toward genetic predilection, metabolic disorders, trauma, infection, radiation or idiopathic reasons are found to be responsible. Available literature reports agenesis most often of third molars, maxillary lateral incisors, mandibular central and lateral incisors, and mandibular second premolars in decreasing order of frequency of occurrence. Males are more often affected than females. Maxillary primary teeth are more often found affected by agenesis than mandibular primary teeth. Available literature reports missing teeth to be found unilaterally or orbilaterally with a predisposition toward a similar phenomenon occurring in the permanent dentition. In congenital agenesis impaired growth of the alveolar process, reduced lower facial height, speech impairment, deep bite, restriction in the movement of the tongue due to ankyloglossia, asymmetry of the affected side of the face are clinical features evident. There has been no report of complete agenesis of primary and permanent teeth in a whole mandibular quadrant in conjunction with the absence of maxillary second and third molars on the affected side. Here, we report an incidence of a rare occurrence of complete agenesis of more than 10 primary and permanent teeth, unilaterally, in the right mandibular quadrant, in a child of 10 years presenting with a chief complaint of several missing primary teeth and difficulty in speech due to its complete absence. Treatment strategies included various orthodontic and restorative procedures to improve esthetics and function. The orthodontic procedures involved expansion of the narrow maxillary arch to obtain a functionally adapted occlusion and creation of space for future alignment, and

  18. Dental Development in Patients with Hypophosphatemia Rickets

    PubMed Central

    AM, Hazza’a

    2010-01-01

    Background Hypophosphatemic Rickets (HR) is a disease that affects mineralized structures including bone and dentine, studies on dental development in these patients are scarce with equivocal results. Aim To assess dental development of a group of children with (HR) and to compare that to healthy matched controls, and to assess relationship between delayed medical treatment and dental development. Materials and methods This is a controlled cross-sectional study carried out on a sample of 21 children with HR and healthy age and sex matched controls, diseased children were diagnosed at different ages. Dental age was assessed using Demirjian et al method. The difference between ages of study and control groups was assessed using t-test, Pearson correlation was used to test relationship between age of commencement of treatment and dental development delay. Results Most HR subjects demonstrated dental delay ranging from 0.2 to 2.5 years which was significant (p-value = 0.028). The difference between dental age of the study and control groups was statistically significant using paired t-test. There was no correlation between age of commencement of treatment and amount of dental delay. Conclusion Dental development was significantly delayed in a group of HR patients compared to matched healthy controls. Delay in commencement of treatment may lead to a permanent deficit in dental development.

  19. Permanent contraception for women.

    PubMed

    Micks, Elizabeth A; Jensen, Jeffrey T

    2015-11-01

    Permanent methods of contraception are used by an estimated 220 million couples worldwide, and are often selected due to convenience, ease of use and lack of side effects. A variety of tubal occlusion techniques are available for female permanent contraception, and procedures can be performed using a transcervical or transabdominal approach. This article reviews currently available techniques for female permanent contraception and discusses considerations when helping patients choose a contraceptive method and tubal occlusion technique.

  20. Dental Implants

    MedlinePlus

    ... Procedures Dental Implants Dentures Direct Bonding Implants versus Bridges Orthodontics and Aligners Periodontal Plastic Surgery Porcelain Crowns Porcelain Fixed Bridges Porcelain Veneers Repairing Chipped Teeth Teeth Whitening Tooth- ...

  1. River restoration

    NASA Astrophysics Data System (ADS)

    Wohl, Ellen; Angermeier, Paul L.; Bledsoe, Brian; Kondolf, G. Mathias; Macdonnell, Larry; Merritt, David M.; Palmer, Margaret A.; Poff, N. Leroy; Tarboton, David

    2005-10-01

    River restoration is at the forefront of applied hydrologic science. However, many river restoration projects are conducted with minimal scientific context. We propose two themes around which a research agenda to advance the scientific basis for river restoration can be built. First, because natural variability is an inherent feature of all river systems, we hypothesize that restoration of process is more likely to succeed than restoration aimed at a fixed end point. Second, because physical, chemical, and biological processes are interconnected in complex ways across watersheds and across timescales, we hypothesize that restoration projects are more likely to be successful in achieving goals if undertaken in the context of entire watersheds. To achieve restoration objectives, the science of river restoration must include (1) an explicit recognition of the known complexities and uncertainties, (2) continued development of a theoretical framework that enables us to identify generalities among river systems and to ask relevant questions, (3) enhancing the science and use of restoration monitoring by measuring the most effective set of variables at the correct scales of measurement, (4) linking science and implementation, and (5) developing methods of restoration that are effective within existing constraints. Key limitations to river restoration include a lack of scientific knowledge of watershed-scale process dynamics, institutional structures that are poorly suited to large-scale adaptive management, and a lack of political support to reestablish delivery of the ecosystem amenities lost through river degradation. This paper outlines an approach for addressing these shortcomings.

  2. Common Dental Anomalies in Cleft Lip and Palate Patients

    PubMed Central

    HAQUE, Sanjida; ALAM, Mohammad Khursheed

    2015-01-01

    Background: Cleft lip and palate (CLP) is the most common orofacial congenital malformation in live births. CLP can occur individually or in combination with other congenital deformities. Affected patients experience a number of dental, aesthetic, speech, hearing, and psychological complications and have a higher incidence of severe dental conditions. The purpose of this study is to characterise the different types of dental anomalies that are frequently associated with CLP patients based on a literature survey. Methods: By literature survey, this study characterises the different types of dental anomalies that are frequently associated with cleft lip and palate patients. Results: Common dental anomalies associated with CLP are supernumerary tooth, congenitally missing tooth, delayed tooth development, morphological anomalies in both deciduous and permanent dentition, delayed eruption of permanent maxillary incisors, microdontia, and abnormal tooth number. Conclusion: The incidence of certain dental anomalies is strongly correlated with Cleft lip and palate, a finding that is consistent with previous studies. PMID:26023296

  3. Successful strategies for matching one or two indirect restorations to natural dentition.

    PubMed

    Sesemann, Michael R

    2011-01-01

    One of the most difficult and noble undertakings of a dental restorative team is to provide an indirect restoration for a compromised tooth surrounded by otherwise healthy, natural dentition. Matching one or two indirect dental restorations to adjacent healthy teeth is a herculean task for both the dentist and laboratory technician. The team must be knowledgeable of the natural dentition's characteristics to best mimic and recreate those same characteristics in a man-made restoration. Knowledge of principles in smile design, dental anatomy, color, characterization, material selection, doctor-technician communication, and clinical acumen are necessary to achieve a successful outcome when matching one or two indirect restorations to natural dentition.

  4. Miniature Pulpotomy of Symptomatic Mature Permanent Teeth: A Report of Two Cases

    PubMed Central

    Asgary, Saeed; Nourzadeh, Mahdieh; Eghbal, Mohammad Jafar

    2016-01-01

    Human dental pulp inflammation can progress to periapical lesion formation and conventional root canal treatment (RCT) has been the traditional method for disease management. This observational study presents two cases of vital pulp therapy in mature molars diagnosed with irreversible pulpitis and associated with apical periodontitis. In these two clinical cases, the involved teeth had deep carious lesions with a history of spontaneous/lingering pain and radiographic examinations revealed the presence of apical radiolucencies. A conservative miniature pulpotomy (MP) using calcium-enriched mixture (CEM) was performed and the teeth were permanently restored with amalgam. Clinical evaluations indicated resolution of pain 24 hours after treatment; the teeth showed normal vitality, remained asymptomatic and maintained normal function after recall examinations. Furthermore, the 18-month radiographic evaluation showed healing of the apical lesions. Vital pulp therapy using the MP technique with CEM appeared successful in avoiding RCT intervention. These two reports of case outcome suggest that simple MP using a CEM bioregenerative technique may provide a favorable outcome for permanent teeth diagnosed with irreversible pulpitis and associated with apical periodontitis. PMID:26843883

  5. Miniature Pulpotomy of Symptomatic Mature Permanent Teeth: A Report of Two Cases.

    PubMed

    Asgary, Saeed; Nourzadeh, Mahdieh; Eghbal, Mohammad Jafar

    2016-01-01

    Human dental pulp inflammation can progress to periapical lesion formation and conventional root canal treatment (RCT) has been the traditional method for disease management. This observational study presents two cases of vital pulp therapy in mature molars diagnosed with irreversible pulpitis and associated with apical periodontitis. In these two clinical cases, the involved teeth had deep carious lesions with a history of spontaneous/lingering pain and radiographic examinations revealed the presence of apical radiolucencies. A conservative miniature pulpotomy (MP) using calcium-enriched mixture (CEM) was performed and the teeth were permanently restored with amalgam. Clinical evaluations indicated resolution of pain 24 hours after treatment; the teeth showed normal vitality, remained asymptomatic and maintained normal function after recall examinations. Furthermore, the 18-month radiographic evaluation showed healing of the apical lesions. Vital pulp therapy using the MP technique with CEM appeared successful in avoiding RCT intervention. These two reports of case outcome suggest that simple MP using a CEM bioregenerative technique may provide a favorable outcome for permanent teeth diagnosed with irreversible pulpitis and associated with apical periodontitis. PMID:26843883

  6. Complete oral rehabilitation in a case with severe dental fluorosis

    PubMed Central

    Joshi, Nikhil; Palaskar, Jayant; Joshi, Mahasweta; Kathariya, Rahul

    2014-01-01

    The authors have presented a technique of full occlusal rehabilitation in a case of severe dental fluorosis. In this technique, maxillary and mandibular anterior teeth were simultaneously prepared and restored first. This was followed by simultaneous preparation of maxillary and mandibular posterior teeth that were restored in canine guided occlusion. The technique and sequence followed here is unique and is not available in dental literature. This technique reduces number of appointments while fulfilling all objectives. Periodontal follow-up over 3 years was satisfactory. A restorative treatment protocol has been devised for fluorosis which will act as a guide for the dental practitioners. PMID:25516876

  7. Associated dental anomalies in an Etruscan adolescent.

    PubMed

    Baccetti, T; Franchi, L; Cecchi, J M; Pacciani, E

    1995-01-01

    Three fragments of the upper jaw of an Etruscan adolescent of the 6th century B.C. discovered at the necropolis of Cancellone 1 (Magliano in Tuscany, Grosseto, Italy) were examined. A triad of associated dental anomalies was found: congenitally missing second premolars, "peg-shaped" permanent lateral incisors, and ectopic (palatal) eruption of a permanent canine. These findings provided the opportunity to discuss etiopathogenetic aspects of the associations among different types of tooth abnormalities. PMID:7726465

  8. Permanent magnet assembly

    DOEpatents

    Chell, Jeremy; Zimm, Carl B.

    2006-12-12

    A permanent magnet assembly is disclosed that is adapted to provide a magnetic field across an arc-shaped gap. Such a permanent magnet assembly can be used, for example, to provide a time-varying magnetic field to an annular region for use in a magnetic refrigerator.

  9. Dental Hygienist.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. Center on Education and Training for Employment.

    This document, which is designed for use in developing a tech prep competency profile for the occupation of dental hygienist, lists technical competencies and competency builders for 13 units pertinent to the health technologies cluster in general and 9 units specific to the occupation of dental hygienist. The following skill areas are covered in…

  10. Can they really be opposite? A new look at four critical aspects of anterior dental morphology.

    PubMed

    Greenberg, Joseph R

    2008-09-01

    Human dental anatomy has not changed significantly in hundreds of years. Dental students and students of dental laboratory technology learn human dental anatomy as fundamental to their didactic work. Yet, so often we see dental restorations that do not follow the accepted basic design criteria of natural teeth. A possible conclusion is that the information was correctly presented as a basic science, but not completely carried over into clinical practice. When visually essential aspects of dental anatomy and composition are not accurately incorporated into esthetic restorations, patients are not completely served, and practitioners may be frustrated as well. This article reviews four essential aspects of anterior dental morphology--anterior tooth width/length proportions, bilateral symmetry, incisal edges, and incisal embrasures--that often are not accurately incorporated into dental restorations, and positions them in an easy to remember format: opposites.

  11. [THE VITAL PULP THERAPY IN PERMANENT TEETH].

    PubMed

    Makowiecki, Piotr; Trusewicz, Matylda; Tyszler, Lukasz; Buczkowska-Radlińska, Jadwiga

    2014-01-01

    The vitality of dental pulp is essential for long-term tooth survival. The aim of vital pulp therapy is to preserve vital, healthy pulp tissue. This therapy's foundation is the elimination of bacteria from the dentin-pulp complex. The treatment option depends on the cause and extent of mineralised tooth tissue destruction. The outcome of such treatment is determined by accurate assessment of the pulp's status and the dentist's ability to predict the success of the therapy. The aim of this review is to facilitate the dentist in making a proper decision referring to vital pulp therapy in permanent teeth, and to provide an overview of new approaches in such treatment.

  12. Permanent tooth sizes in 46,XY females.

    PubMed Central

    Alvesalo, L; Varrela, J

    1980-01-01

    The teeth of seven Finnish patients with complete testicular-feminization syndrome (46,XY females) were studied to obtain further information about their growth and possible somatic determinants on the Y chromosome. The sizes of the permanent teeth of the 46,XY females were found to be as large as those of control males and definitely larger than those of control females. Testicular feminization is caused by androgen insensitivity, and persons affected are phenotypically females. Hence, these results also indicate the influence of the Y chromosome on dental determination. PMID:7424913

  13. Seven-year clinical evaluation of painful cracked teeth restored with a direct composite restoration.

    PubMed

    Opdam, Niek J M; Roeters, Joost J M; Loomans, Bas A C; Bronkhorst, Ewald M

    2008-07-01

    The purpose of this study was to investigate long-term clinical effectiveness of treating painful cracked teeth with a direct bonded composite resin restoration. The hypothesis tested was that cracked teeth treated with or without cuspal coverage showed the same performance. Forty-one patients attended a dental practice with a painful cracked tooth that was restored with a direct composite resin restoration. Twenty teeth were restored without and 21 with cuspal coverage. After 7 years, 40 teeth could be evaluated. Three teeth without cuspal coverage needed an endodontic treatment, of which 2 failed as a result of fracture. No significant differences were found for tooth or pulp survival. Three more repairable restoration failures were recorded. Mean annual failure rate of restorations without cuspal coverage was 6%; no failures in restorations with cuspal coverage occurred (P = .009). A direct bonded composite resin restoration can be a successful treatment for a cracked tooth.

  14. Dental Caries Experience and Use of Dental Services among Brazilian Prisoners

    PubMed Central

    Leite Cavalcanti, Alessandro; Araujo Rodrigues, Iris Sant´Anna; de Melo Silveira, Ingrid Thays; Sarmento de Oliveira, Thaliny Batista; de Almeida Pinto, Magaly Suenya; Cabral Xavier, Alidianne Fabia; Dias de Castro, Ricardo; Nascimento Padilha, Wilton Wilney

    2014-01-01

    This ross-sectional study involving 127 male prisoners evaluates the use of dental services and dental caries among Brazilian inmates. Data were collected by interview and clinical examination. Sociodemographic and sentencing information as well as use of dental services, self-reported dental morbidity, self-perception, and oral health impacts were investigated. The mean DMFT index value was 19.72. Of the components, the decayed component showed the highest mean value (11.06 ± 5.37). Statistically significant association was found between DMFTs with values from 22 to 32 and oral health satisfaction (p = 0.002), difficulty speaking (p = 0.024), shame of talking (p = 0.004) and smiling (p < 0.001). Regarding the use of dental services, 80% had their last dental appointment less than one year ago, with most visits occurring in prison (80%), with restorative treatment (32%), followed by dental pain (26.4%), being the main reasons for such appointments. Most prisoners used dental services provided by the prison. Although restorative treatment has been the main reason for the use of dental services, “decayed” and “missing” components contributed to the high mean DMFT index. PMID:25429680

  15. Dental caries experience and use of dental services among Brazilian prisoners.

    PubMed

    Cavalcanti, Alessandro Leite; Rodrigues, Iris Sant Anna Araujo; de Melo Silveira, Ingrid Thays; de Oliveira, Thaliny Batista Sarmento; de Almeida Pinto, Magaly Suenya; Xavier, Alidianne Fabia Cabral; de Castro, Ricardo Dias; Padilha, Wilton Wilney Nascimento

    2014-11-25

    This ross-sectional study involving 127 male prisoners evaluates the use of dental services and dental caries among Brazilian inmates. Data were collected by interview and clinical examination. Sociodemographic and sentencing information as well as use of dental services, self-reported dental morbidity, self-perception, and oral health impacts were investigated. The mean DMFT index value was 19.72. Of the components, the decayed component showed the highest mean value (11.06 ± 5.37). Statistically significant association was found between DMFTs with values from 22 to 32 and oral health satisfaction (p = 0.002), difficulty speaking (p = 0.024), shame of talking (p = 0.004) and smiling (p < 0.001). Regarding the use of dental services, 80% had their last dental appointment less than one year ago, with most visits occurring in prison (80%), with restorative treatment (32%), followed by dental pain (26.4%), being the main reasons for such appointments. Most prisoners used dental services provided by the prison. Although restorative treatment has been the main reason for the use of dental services, "decayed" and "missing" components contributed to the high mean DMFT index.

  16. Replantation after extended dry storage of avulsed permanent incisors: report of a case.

    PubMed

    Cobankara, Funda Kont; Ungor, Mete

    2007-08-01

    A 15-year-old boy lost his maxillary right and left central incisor teeth in a bicycle accident. He was referred to our clinic 1 week after the injury. The crown-root integrities of both the teeth were not damaged. Although the teeth were stored under dry conditions for 1 week, reimplantation of the teeth was planned to retain the teeth in the mouth for as long a period as possible because of the patient's age. Following the debridement and sterilization of root surfaces in 2.5% NaOCl, root canals were prepared and filled with calcium hydroxide. Then, about 2 mm of the apexes were resected to ensure that the roots easily seated in the alveolar socket and the prepared cavities in root ends were obturated with the amalgam. The teeth were placed into their respective sockets and splinted temporarily. The root canal therapy was completed 5 weeks later. Ankylosis was observed radiographically after 10 months. The patient is now 23 years old and he is still able to use both the central incisors functionally. However, there is a pink appearance on the cervical buccal surface of left central incisor because of progressive replacement resorption. In this case, the new treatment plan is to perform a permanent restoration with dental implants following the extraction of both teeth. Even though the long-term prognosis is uncertain, this treatment technique has provided an advantage for the patient in his adolescent period by maintaining the height of alveolar bone and making the provision of an aesthetically acceptable permanent restoration at a later age possible.

  17. Preservation & Restoration.

    ERIC Educational Resources Information Center

    Online-Offline, 2000

    2000-01-01

    This theme issue on preservation and restoration presents selected resources for elementary and secondary education that include Web sites, CD-ROM and software, videos, books, magazines, and professional resources as well as classroom activities. Age levels are specified for most materials. I Sidebars discuss restoring a masterpiece, a bug's life,…

  18. [Prosthetic rehabilitation of partially edentulous patients: fixed - removable - combined? Metal - ceramics - all - ceramics? Implants? Anything goes! Part 2: two case studies represent the fixed, respectively the combined fixed-removable prosthetic restoration by utilization of implants].

    PubMed

    Schnabl, Dagmar

    2015-01-01

    The prosthetic rehabilitation of two partially edentulous patients is presented: one Patient was restored by permanent crowns and bridges attached to natural teeth and to implants, the second was treated by crowns attached to natural teeth and removable implant- supported prostheses. Depending on esthetic requirements and the localization of preparation margins all- or metal-ceramics were used for single crowns, metal-ceramics was used for bridges. In general, a well coordinated cooperation of dentist, surgeon and dental technician in treatment planning and realization is required for a successful prosthetic rehabilitation. PMID:25734274

  19. [Prosthetic rehabilitation of partially edentulous patients: fixed - removable - combined? Metal - ceramics - all - ceramics? Implants? Anything goes! Part 2: two case studies represent the fixed, respectively the combined fixed-removable prosthetic restoration by utilization of implants].

    PubMed

    Schnabl, Dagmar

    2015-01-01

    The prosthetic rehabilitation of two partially edentulous patients is presented: one Patient was restored by permanent crowns and bridges attached to natural teeth and to implants, the second was treated by crowns attached to natural teeth and removable implant- supported prostheses. Depending on esthetic requirements and the localization of preparation margins all- or metal-ceramics were used for single crowns, metal-ceramics was used for bridges. In general, a well coordinated cooperation of dentist, surgeon and dental technician in treatment planning and realization is required for a successful prosthetic rehabilitation.

  20. Oral health status, dental anxiety, and behavior-management problems in children with oppositional defiant disorder.

    PubMed

    Aminabadi, Naser A; Najafpour, Ebrahim; Erfanparast, Leila; Jamali, Zahra; Pournaghi-Azar, Fatemeh; Tamjid-Shabestari, Shabnam; Shirazi, Sajjad

    2016-02-01

    Mental disorders have been shown to affect children's oral health. This study was carried out to investigate the oral health status, dental anxiety (DA), and behavior-management problems (BMPs) during dental treatment in 6- to 9-yr-old children with oppositional defiant disorder (ODD)/attention-deficit hyperactivity disorder (ADHD). The study and control groups included 40 children with ODD/ADHD and 80 normal children, respectively. All participants received an amalgam restoration. During the procedure, the children's behavior was assessed using the Frankl Rating Scale and the Verbal Skill Scale. Parents rated their children's DA using the parental version of the Children's Fear Survey Schedule-Dental subscale (CFSS-DS). Comorbid anxiety disorders were assessed using the Kiddie-Sads-Present and Lifetime Version questionnaire. Oral health status was assessed using the gingival index and the decayed, missing, and filled teeth score for permanent (DMFT) and primary (dmft) teeth. The findings showed that DA and BMPs were significantly higher in children with ODD/ADHD than in the controls. Furthermore, the frequency of DA and BMPs was higher in children with both ODD/ADHD and a comorbid anxiety disorder than in those without comorbid anxiety disorder. Children with ODD/ADHD had significantly higher DMFT/dmft scores than those in the control group, whereas the difference in gingival index was not statistically significant. In conclusion, children with ODD/ADHD had higher levels of DA, BMP and poorer oral health status. PMID:26707341

  1. Oral health status, dental anxiety, and behavior-management problems in children with oppositional defiant disorder.

    PubMed

    Aminabadi, Naser A; Najafpour, Ebrahim; Erfanparast, Leila; Jamali, Zahra; Pournaghi-Azar, Fatemeh; Tamjid-Shabestari, Shabnam; Shirazi, Sajjad

    2016-02-01

    Mental disorders have been shown to affect children's oral health. This study was carried out to investigate the oral health status, dental anxiety (DA), and behavior-management problems (BMPs) during dental treatment in 6- to 9-yr-old children with oppositional defiant disorder (ODD)/attention-deficit hyperactivity disorder (ADHD). The study and control groups included 40 children with ODD/ADHD and 80 normal children, respectively. All participants received an amalgam restoration. During the procedure, the children's behavior was assessed using the Frankl Rating Scale and the Verbal Skill Scale. Parents rated their children's DA using the parental version of the Children's Fear Survey Schedule-Dental subscale (CFSS-DS). Comorbid anxiety disorders were assessed using the Kiddie-Sads-Present and Lifetime Version questionnaire. Oral health status was assessed using the gingival index and the decayed, missing, and filled teeth score for permanent (DMFT) and primary (dmft) teeth. The findings showed that DA and BMPs were significantly higher in children with ODD/ADHD than in the controls. Furthermore, the frequency of DA and BMPs was higher in children with both ODD/ADHD and a comorbid anxiety disorder than in those without comorbid anxiety disorder. Children with ODD/ADHD had significantly higher DMFT/dmft scores than those in the control group, whereas the difference in gingival index was not statistically significant. In conclusion, children with ODD/ADHD had higher levels of DA, BMP and poorer oral health status.

  2. Development of dental ceramics. An historical perspective.

    PubMed

    Jones, D W

    1985-10-01

    This article covers the inception and development of porcelain and its adoption into dentistry as a restorative material substituting for natural tooth. The turbulent years of development of dental porcelain with the innumerable waxing and waning fortunes of its acceptance and success are outlined. The major milestones in the historical and scientific development and refinements of dental porcelain materials are covered from its earliest beginnings to modern day materials.

  3. Ablation by-products of dental materials from the Er:YAG laser and the dental handpiece

    NASA Astrophysics Data System (ADS)

    Wigdor, Harvey A.; Visuri, Steven R.; Walsh, Joseph T., Jr.

    1995-05-01

    Recently there has been much interest in lasers and their potential use to replace the dental drill. The research has been directed towards vital dental tissues. It must be understood that any laser to be used in dentistry which will replace the dental drill must also ablate and remove existing dental materials. Some concern exists about the ablation products when the Er:YAG laser is used to ablate dental materials. It is incumbent on the professionals using these lasers to understand the materials being produced by these lasers and protect themselves and their patients from possible toxic products. It is the intent of this paper to evaluate the products produced by the ablation of both dental amalgam and composite dental restorative materials and compare them with those produced by the traditional dental handpiece (drill).

  4. Dental Fluorosis

    MedlinePlus

    ... when children regularly consume fluoride during the teeth-forming years, age 8 and younger. Most dental fluorosis ... over a long period when the teeth are forming under the gums. Only children aged 8 years ...

  5. A preventive dental care programme at the workplace.

    PubMed

    Westerman, B

    1993-06-01

    Employees from an industrial group in Brisbane were examined at the workplace and found to have generally low levels of dental disease. At the same time, the Australian Bureau of Statistics suggests that less than 45 per cent of Australians attend a dentist annually. This low attendance for regular dental care reduces the effectiveness of any preventive dental service. A pilot scheme of preventive dental care was provided for employees at the workplace in Brisbane. The aim of the programme was to provide regular health counselling and reinforcement of oral health activities, general dental information, regular prophylaxis, scaling and cleaning, and referrals for restorative care. The preventive programme was appropriate given the disease levels. The services were effective in improving the periodontal status and restorative care which resulted from referrals. As well, the preventive dental care programme proved to be readily acceptable to both employees and management.

  6. Current status of zirconia restoration.

    PubMed

    Miyazaki, Takashi; Nakamura, Takashi; Matsumura, Hideo; Ban, Seiji; Kobayashi, Taira

    2013-10-01

    During the past decade, zirconia-based ceramics have been successfully introduced into the clinic to fabricate fixed dental prostheses (FDPs), along with a dental computer-aided/computer-aided manufacturing (CAD/CAM) system. In this article (1) development of dental ceramics, (2) the current status of dental CAD/CAM systems, (3) CAD/CAM and zirconia restoration, (4) bond between zirconia and veneering ceramics, (5) bond of zirconia with resin-based luting agents, (6) surface finish of zirconia restoration and antagonist enamel wear, and (7) clinical evaluation of zirconia restoration are reviewed. Yttria partially stabilized tetragonal zirconia polycrystalline (Y-TZP) showed better mechanical properties and superior resistance to fracture than other conventional dental ceramics. Furthermore, ceria-stabilized tetragonal zirconia polycrystalline and alumina nanocomposites (Ce-TZP/A) had the highest fracture toughness and had resistance to low-temperature aging degradation. Both zirconia-based ceramics have been clinically available as an alternative to the metal framework for fixed dental prostheses (FDPs). Marginal adaptation of zirconia-based FDPs is acceptable for clinical application. The most frequent clinical complication with zirconia-based FDPs was chipping of the veneering porcelain that was affected by many factors. The mechanism for the bonding between zirconia and veneering ceramics remains unknown. There was no clear evidence of chemical bonding and the bond strength between zirconia and porcelain was lower than that between metal and porcelain. There were two alternatives proposed that might avoid chipping of veneering porcelains. One was hybrid-structured FDPs comprising CAD/CAM-fabricated porcelain parts adhering to a CAD/CAM fabricated zirconia framework. Another option was full-contour zirconia FDPs using high translucent zirconia. Combined application of silica coating and/or silane coupler, and 10-methacryloyloxydecyl dihydrogen phosphate is

  7. Current status of zirconia restoration.

    PubMed

    Miyazaki, Takashi; Nakamura, Takashi; Matsumura, Hideo; Ban, Seiji; Kobayashi, Taira

    2013-10-01

    During the past decade, zirconia-based ceramics have been successfully introduced into the clinic to fabricate fixed dental prostheses (FDPs), along with a dental computer-aided/computer-aided manufacturing (CAD/CAM) system. In this article (1) development of dental ceramics, (2) the current status of dental CAD/CAM systems, (3) CAD/CAM and zirconia restoration, (4) bond between zirconia and veneering ceramics, (5) bond of zirconia with resin-based luting agents, (6) surface finish of zirconia restoration and antagonist enamel wear, and (7) clinical evaluation of zirconia restoration are reviewed. Yttria partially stabilized tetragonal zirconia polycrystalline (Y-TZP) showed better mechanical properties and superior resistance to fracture than other conventional dental ceramics. Furthermore, ceria-stabilized tetragonal zirconia polycrystalline and alumina nanocomposites (Ce-TZP/A) had the highest fracture toughness and had resistance to low-temperature aging degradation. Both zirconia-based ceramics have been clinically available as an alternative to the metal framework for fixed dental prostheses (FDPs). Marginal adaptation of zirconia-based FDPs is acceptable for clinical application. The most frequent clinical complication with zirconia-based FDPs was chipping of the veneering porcelain that was affected by many factors. The mechanism for the bonding between zirconia and veneering ceramics remains unknown. There was no clear evidence of chemical bonding and the bond strength between zirconia and porcelain was lower than that between metal and porcelain. There were two alternatives proposed that might avoid chipping of veneering porcelains. One was hybrid-structured FDPs comprising CAD/CAM-fabricated porcelain parts adhering to a CAD/CAM fabricated zirconia framework. Another option was full-contour zirconia FDPs using high translucent zirconia. Combined application of silica coating and/or silane coupler, and 10-methacryloyloxydecyl dihydrogen phosphate is

  8. Dental students' perception of patient anxiety.

    PubMed

    Lodge, J; Tripp, G

    1993-04-01

    This study examined the ability of dental students to assess patients' anxiety during dental treatment, and the relationship between patients' general, waiting room and clinic levels of anxiety. Sixty-six restorative dental patients and 35 Final-year dental students participated in the study. Prior to a routine dental appointment, patients completed visual analogue scales indicating their general and waiting room levels of anxiety. During treatment, patients and dental students completed similar scales to indicate patients' levels of anxiety up to and at that time. Patients' general and waiting room levels of anxiety were found to correlate significantly with their reports of anxiety during treatment. Female patients reported higher levels of anxiety than male patients. The correlations between patient and student ratings of patients' anxiety were small and non-significant, suggesting the students were not accurate in their estimates of patients' anxiety during treatment. It is suggested, therefore, that dental students be encouraged to ask patients directly how they are feeling about the dental situation. Such discussion could take place prior to, or at the beginning of, the dental appointment.

  9. Income, income inequality, dental caries and dental care levels: an ecological study in rich countries.

    PubMed

    Bernabé, E; Sheiham, A; Sabbah, W

    2009-01-01

    Research has shown that beyond a certain level of absolute income, there is a weak relationship between income and population health. On the other hand, relative income or income inequality is more strongly related to health than absolute income in rich countries. The objective of this study was to assess the relationships of income and income inequality with dental caries and dental care levels in 35- to 44-year-old adults among rich countries. Income was assessed by gross domestic product and gross national income, income inequality by Gini coefficient and the ratio between the income of the richest and poorest 20% of the population, dental caries by DMFT and dental care levels by the care, restorative and treatment indices. Pearson and partial correlation were used to examine the relationships between income, income inequality, caries experience and dental care. Income measures were not related to either dental caries or dental care levels. However, income inequality measures were inversely and significantly related to number of filled teeth, DMFT, care index and restorative index, but not to number of decayed or missing teeth. It is concluded that DMFT scores were higher in more equal countries and may be explained by greater levels of restorative care in those countries.

  10. Basic concepts and techniques of dental implants.

    PubMed

    Tagliareni, Jonathan M; Clarkson, Earl

    2015-04-01

    Dental implants provide completely edentulous and partial edentulous patients the function and esthetics they had with natural dentition. It is critical to understand and apply predictable surgical principles when treatment planning and surgically restoring edentulous spaces with implants. This article defines basic implant concepts that should be meticulously followed for predictable results when treating patients and restoring dental implants. Topics include biological and functional considerations, biomechanical considerations, preoperative assessments, medical history and risk assessments, oral examinations, radiographic examinations, contraindications, and general treatment planning options. PMID:25835792

  11. Basic concepts and techniques of dental implants.

    PubMed

    Tagliareni, Jonathan M; Clarkson, Earl

    2015-04-01

    Dental implants provide completely edentulous and partial edentulous patients the function and esthetics they had with natural dentition. It is critical to understand and apply predictable surgical principles when treatment planning and surgically restoring edentulous spaces with implants. This article defines basic implant concepts that should be meticulously followed for predictable results when treating patients and restoring dental implants. Topics include biological and functional considerations, biomechanical considerations, preoperative assessments, medical history and risk assessments, oral examinations, radiographic examinations, contraindications, and general treatment planning options.

  12. Optical approach in characterizing dental biomaterials

    NASA Astrophysics Data System (ADS)

    Demoli, Nazif; Vučić, Zlatko; Milat, Ognjen; Gladić, Jadranko; Lovrić, Davorin; Pandurić, Vlatko; Marović, Danijela; Moguš-Milanković, Andrea; Ristić, Mira; Čalogović, Marina; Tarle, Zrinka

    2013-04-01

    The purpose of this paper is to present the current activities of a research collaborative program between three institutions from Zagreb (School of Dental Medicine, Institute of Physics, and Institute Ruđer Bo\\vsković). Within the scope of this program, it is planned to investigate and find guidelines for the refinement of the properties of dental biomaterials (DBs) and of procedures in restorative dental medicine. It is also planned to identify and model the dominant mechanisms which control polymerization of DBs. The materials to be investigated include methacrylate based composite resins, new composite materials with amorphous calcium phosphate, silorane based composite resins, glass-ionomer cements, and giomer.

  13. Methods to preclude aspiration or swallowing of dental appliances.

    PubMed

    Zakaria, A A

    1975-05-01

    A technique which precludes the swallowing of dental restorations during fitting and cementation has been described. An alternative technique is to spot-weld a small loop or wire to the finished crown. Dental floss may be attached to the loop. Another method is to attach a piece of unwaxed floss to the completed crown with Eastman adhesive 910. The floss is removed after the restoration is cemented.

  14. CAMBRA: An Examination of Change in the Dental Profession

    ERIC Educational Resources Information Center

    Young, Douglas

    2010-01-01

    Dental caries is a disease process, one that will not be eliminated by tooth repair alone. Caries is the most prevalent disease of children and the primary reason for most restorative dental visits in both adults and children. A risk-based approach to managing caries targets those in greatest jeopardy for contracting the disease and provides…

  15. Teaching dental anatomy with light-activated resins.

    PubMed

    Chalkley, Y; Denehy, G E; Schulein, T M

    1984-04-01

    A method has been described in which light-activated resins are incorporated into the dental anatomy laboratory. This procedure is a valuable addition to the anatomy course because students (1) work with a restorative material appropriate for anterior teeth, (2) learn the unique properties of the light-activated resins, and (3) apply the principles of dental anatomy to a clinically relevant task.

  16. Treatment of trauma to the primary and young permanent dentitions.

    PubMed

    García-Godoy, F; Pulver, F

    2000-07-01

    An overview of the various possibilities for trauma to the primary and young permanent dentition has been presented. Appropriate treatment procedures have been described. Advances in dental science have been great, and dental materials have become superior to what they were just a few years ago. The dentist must never forget the variabilities of human responses to any of the treatment techniques, however, and the dentist must never be dogmatic in approach. The dentist should be able to diagnose, interpret, and alter any of the treatment techniques as more scientific evidence is obtained.

  17. An evidence-based review of dental matrix systems.

    PubMed

    Owens, Barry M; Phebus, Jeffrey G

    2016-01-01

    The restoration of proximal surface cavities, originating from Class II carious lesions, to "normal" anatomical specifications is a fundamental objective for the dental practitioner. Cognitive interpretation of tooth morphology attained from evidence-based resources, together with the necessary psychomotor skills for correct design and completion, are considered essential strategies for restoration success. Also, the visualization of the original tooth structure, if present, should substantially benefit the dentist in the creation of a clinically satisfactory restoration. The purpose of this evidence-based review is to define the cause and effect of decisions based on optimum treatment standards of care for the patient. The concepts of form and function, as related to the oral environment, and the consequences of unsatisfactory dental restorative care will be scrutinized. This article will identify and explain the different challenges and solutions for restoration of dental proximal lesions and provide an overview of past, present, and future procedures. PMID:27599285

  18. The utilization of dental hygiene students in school-based dental sealant programs.

    PubMed

    Miller, Faith Y

    2005-01-01

    Early detection of childhood caries is important to childrens' overall health. Untreated childhood caries can lead to pain, as in abscesses from prolonged neglect; altered dietary intake; and delays in the development of the permanent teeth if the primary teeth are prematurely lost. In the summer of 2000, funds were provided to various oral health care provider organizations by the Illinois Department of Public Health, Division of Oral Health, to purchase portable equipment to deliver preventive services (i.e., exams, sealants, and oral hygiene education) to second-grade and sixth-grade children who qualified for Medicaid and/or free and reduced-cost lunch programs. The Dental Sealant Grant Program at Southern Illinois University in Carbondale was a unique program that utilized dental hygiene students as the primary human resource. Within the state, the Dental Sealant Grant Program was, at the time of this report, the only grantee sponsored by a stand-alone dental hygiene program (not affiliated with a dental school). Other positive aspects of the dental hygiene-sponsored sealant program were that the supervising dentist was the primary Medicaid provider and a member of the dental hygiene faculty; dental hygiene faculty participated actively as site coordinators and clinicians; and dental hygiene students were given the opportunity to volunteer for the program as a service-learning option. PMID:16297312

  19. Highest permanent human habitation.

    PubMed

    West, John B

    2002-01-01

    The aim of this analysis was to determine the altitude of the highest permanent human habitation in the hope that this will throw some light on what determines the highest altitude that a community can tolerate indefinitely. A number of places where people have lived at very high altitudes for long periods of time are reviewed. Individuals have lived for as long as 2 yr at an altitude of 5950 m, and there was a miner's camp at 5300 m for several years. The highest permanently inhabited town in the world at the present time appears to be La Rinconada, a mining village of over 7000 people in southern Peru at an altitude of up to 5100 m, which has been in existence for over 40 yr. The altitude of the highest permanent human habitation is determined partly by economic factors, rather than solely by human tolerance to hypoxia. PMID:12631426

  20. Dental surgery in ancient Egypt.

    PubMed

    Blomstedt, Patric

    2013-01-01

    Many different surgical procedures have over the years been attributed to the ancient Egyptians. This is also true regarding the field of dental surgery. The existence of dentists in ancient Egypt is documented and several recipes exist concerning dental conditions. However, no indications of dental surgery are found in the medical papyri or in the visual arts. Regarding the osteological material/mummies, the possible indications of dental surgery are few and weak. There is not a single example of a clear tooth extraction, nor of a filling or of an artificial tooth. The suggested examples of evacuation of apical abscesses can be more readily explained as outflow sinuses. Regarding the suggested bridges, these are constituted of one find likely dating to the Old Kingdom, and one possibly, but perhaps more likely, dating to the Ptolemaic era. Both seem to be too weak to have served any possible practical purpose in a living patient, and the most likely explanation would be to consider them as a restoration performed during the mummification process. Thus, while a form of dentistry did certainly exist in ancient Egypt, there is today no evidence of dental surgery.

  1. Zirconia Crown as Single Unit Tooth Restoration: A Literature Review.

    PubMed

    Alfawaz, Yasser

    2016-01-01

    Ceramics has become increasingly popular as a dental restorative material because of its superior esthetics, as well as its inertness and biocompatibility. Among dental ceramics, zirconia is used as a dental biomaterial and it is the material of choice in contemporary restorative dentistry. Zirconia ceramics has both clinical popularity and success due to its outstanding mechanical properties and ease of machining in the green stage via computer-aided design and computer-aided manufacturing technology. Zirconia is one of the most promising restorative biomaterial because it has favorable mechanical and chemical properties suitable for medical application. Zirconia ceramics is becoming a prevalent biomaterial in dentistry. Clinical evaluations also indicate a good success rate for zirconia with minimal complications. This article reviews the current literature on dental zirconia with respect to basic properties, biocompatibility, and clinical applications in aesthetic dentistry as single unit crown. PMID:27443370

  2. Dental Calculus Arrest of Dental Caries

    PubMed Central

    Keyes, Paul H.; Rams, Thomas E.

    2016-01-01

    Background An inverse relationship between dental calculus mineralization and dental caries demineralization on teeth has been noted in some studies. Dental calculus may even form superficial layers over existing dental caries and arrest their progression, but this phenomenon has been only rarely documented and infrequently considered in the field of Cariology. To further assess the occurrence of dental calculus arrest of dental caries, this study evaluated a large number of extracted human teeth for the presence and location of dental caries, dental calculus, and dental plaque biofilms. Materials and methods A total of 1,200 teeth were preserved in 10% buffered formal saline, and viewed while moist by a single experienced examiner using a research stereomicroscope at 15-25× magnification. Representative teeth were sectioned and photographed, and their dental plaque biofilms subjected to gram-stain examination with light microscopy at 100× magnification. Results Dental calculus was observed on 1,140 (95%) of the extracted human teeth, and no dental carious lesions were found underlying dental calculus-covered surfaces on 1,139 of these teeth. However, dental calculus arrest of dental caries was found on one (0.54%) of 187 evaluated teeth that presented with unrestored proximal enamel caries. On the distal surface of a maxillary premolar tooth, dental calculus mineralization filled the outer surface cavitation of an incipient dental caries lesion. The dental calculus-covered carious lesion extended only slightly into enamel, and exhibited a brown pigmentation characteristic of inactive or arrested dental caries. In contrast, the tooth's mesial surface, without a superficial layer of dental calculus, had a large carious lesion going through enamel and deep into dentin. Conclusions These observations further document the potential protective effects of dental calculus mineralization against dental caries. PMID:27446993

  3. Health promotion and dental caries.

    PubMed

    Maltz, Marisa; Jardim, Juliana Jobim; Alves, Luana Severo

    2010-01-01

    The central idea of the Brazilian health system is to prevent the establishment of disease or detect it as early as possible. Prevention and treatment of dental caries are related to behavioral factors, including dietary and oral hygiene habits, which are related to many chronic diseases. Dental health promotion therefore should be fully integrated into broadly based health-promoting strategies and actions such as food and health policies, and general hygiene (including oral hygiene), among others. For decades, a linear relationship between sugar consumption and caries has been observed. Recent data has indicated that this relationship is not as strong as it used to be before the widespread use of fluoride. However, diet is still a key factor acting in the carious process. Oral hygiene is a major aspect when it comes to caries, since dental biofilm is its etiological factor. Oral hygiene procedures are effective in controlling dental caries, especially if plaque removal is performed adequately and associated with fluoride. An alternative to a more efficient biofilm control in occlusal areas is the use of dental sealants, which are only indicated for caries-active individuals. If a cavity is formed as a consequence of the metabolic activity of the biofilm, a restorative material or a sealant can be placed to block access of the biofilm to the oral environment in order to prevent caries progress. The prevention of dental caries based on common risk-factor strategies (diet and hygiene) should be supplemented by more disease-specific policies such as rational use of fluoride, and evidence-based dental health care.

  4. Long-term esthetic provisional restorations in dentistry.

    PubMed

    Lodding, D W

    1997-01-01

    The role of interim dental restorations used for indirect restorative and prosthodontic procedures has changed dramatically in the past several years. These restorations are no longer regarded as temporary restorations but rather as provisional restorations with distinct functions and purposes. Provisional restorations have become a vital diagnostic and assessment tool to evaluate function color, shape, contour, occlusion, periodontal response, implant healing, and overall esthetics. An accurate fit and margination is essential to insure and maintain pulpal health of the tooth. With increased demands being placed on provisional restorations, new materials and techniques are being developed and some existing protocols are being refined to accomplish the desired goals. Provisional restorations are often in the oral environment for several months, requiring a well-fabricated and stable restoration. This review is designed to report on current materials, techniques, and concepts in fabricating and maintaining long-term esthetic provisionals.

  5. Bionic restorative system: its potential value in caries therapy.

    PubMed

    He, M M Hao; Zheng, M M Ren; Lin, M D Yinghe

    2009-07-01

    Dental defect caused by dental caries is usually restored by fillings, inlays or onlays at the present day. Although the therapeutic effects of these methods have already been confirmed, complications occasionally set in, such as pulp injury, fracture and secondary caries. Bionic dental organic center possesses similar functions of the natural dental organic center. So we put forward a hypothesis that bionic organic center can be transplanted onto the conditioned pulpal walls of the prepared cavity and a specific filling material, which the cavity will be filled with, provides oxygen, nutrition and raw materials for it to regenerate the lost odontal tissue in vivo. The regenerated odontal tissue which has similar properties of the healthy odontal tissue will restore the defect and it will be combined with the residual odontal tissue tightly, not only in physical structure but also in function. Then the teeth suffering from dental caries could live and function like healthy ones.

  6. Small cross-sectional survey of composite restoration attributes associated with choices for replacement.

    PubMed

    Parpaiola, Alessandra Ramos; Guimarães, Priscilla Santos; França, Fabiana Mantovani Gomes; Basting, Roberta Tarkany

    2009-01-01

    The aim of this work was to present a small cross-sectional survey of composite restoration clinical attributes associated with choices for replacement. Ninety-four composite fillings selected to be replaced were included in this study. A questionnaire was filled out after each procedure in order to assess the clinical conditions that indicated the restoration replacement (marginal staining, unsatisfactory restoration anatomy, marginal fracture, fractured restoration body, painful symptoms, dental fracture, composite discoloration and/or restoration displacement). These conditions could be combined. The chi-square and Exact Fisher tests were performed to analyze the different variables (p < 0.05). The results showed that composite shade discoloration was the main cause of restoration replacement (63.8%). Marginal staining (50%), unsatisfactory restoration anatomy (50%), marginal fracture (14.9%), painful symptoms (8.5%), fractured restoration body (4.3%), dental fracture (1.1%) and total displacement of the restoration (1.1%) were conditions that could be associated. The main cause of dental composite restoration replacement was material shade mismatch with the dental structure (anterior teeth) or marginal staining and unsatisfactory restoration shape (posterior teeth). Marginal staining and composite shade discoloration contrasting with dental structure were related to the presence of caries.

  7. Dental dam patch: an effective intraoral repair technique using cyanoacrylate.

    PubMed

    Liebenberg, W H

    1998-10-01

    Secondary dental dam retention is a critical component of successful dental dam isolation and relates to the provision of an effective seal at the dam/tooth junction. Restorative success can be compromised if this seal is inadvertently interrupted during the operative effort. One such periodic mishap is entanglement of the bur and the interdental dam strip during caries or restorative removal. This invariably results in a gaping interproximal defect in the dam. This article discusses the importance of optimum isolation as it relates to current "wet bonding" adhesive procedures, and introduces a repair technique using a patch of dental dam and cyanoacrylate.

  8. Natural look in volume restoration.

    PubMed

    Lupo, Mary P

    2008-09-01

    Filling and volumizing injection procedures are currently widely used for facial augmentation and re-establishing a youthful appearance. Aesthetic physicians have advanced from the practice of treating single lines and wrinkles towards filling large facial areas to globally restore natural facial contours and meet patient demand for nonsurgical rejuvenation. This review describes the different categories of fillers and volumizers based on their duration of action and ability to create a natural looking effect; they can be broadly classified as temporary or long-lasting biodegradable agents, or permanent nonbiodegradable agents. Temporary fillers are effective to correct lines and wrinkles, but may not adequately meet the need for global facial rejuvenation and volume replacement in a long-term, cost-efficient manner. Permanent fillers for global restoration pose the issue of long-term safety, and may not be compatible with changes in facial architecture with continued aging. Longer lasting volumizers provide patients with a durable, effective option for the restoration of facial volume and the re-establishment of youthful facial contours. Temporary fillers and volumizers may also be used in combination to provide a wide source of options for the global restoration and rejuvenation of the face.

  9. Treating dental caries as an infectious disease. Applying the medical model in practice to prevent dental caries.

    PubMed

    Limeback, H

    1996-01-01

    The above diagnostic and treatment principles may be self evident to most dental practitioners. To many, however, this treatment philosophy is a new one. Continuing dental education and quality assurance programs will play a significant role in helping dentists make the philosophical shift from a highly technical restorative approach to one that uses the medical model and treats dental caries as an infectious disease. While a total cure in humans suffering from dental disease may never be attainable, dental practitioners should soon be better able to direct more of their attention to the patients who already demonstrate a high incidence of dental decay and to those who are clearly at risk to develop future dental decay. PMID:9470624

  10. Material and clinical considerations for full-coverage indirect restorations.

    PubMed

    Martin, Margaret P

    2012-11-01

    Because dental ceramics have been used for decades and continuously improved over the years, there is a plethora of information regarding their material characteristics, applications, and contraindications. Each restorative ceramic material demonstrates benefits and disadvantages, making it difficult for dentists to research, retain, and apply the ideal material for individual restorations and/or combination cases. This article outlines the applications and benefits of dental ceramics in general and examines and reviews the current ceramic alternatives available for restorative dentistry today. It also discusses the material composition and properties of a recently introduced new classification of indirect material: resin nano-ceramic.

  11. Microveneering technique for esthetic enhancement of monolithic zirconia restorations.

    PubMed

    Kurbad, Andreas

    2016-01-01

    The importance of monolithic ceramic restorations is growing, given the safe and cost-effective options for fabrication of such dental crowns and fixed dental prostheses. The optical characteristics of traditional zirconia do not suffice for this purpose. Improved restorative materials that can achieve satisfactory results in posterior restorations have been proposed to solve the problem. In the anterior region, however, even "esthetic" zirconia ceramic is unable to attain results comparable to those of glass-ceramic. Microveneering is a simple, reliable, and timesaving solution. Minimal reduction and veneering can significantly improve the results. A characteristic case is presented here. PMID:27274564

  12. The effect of low-level laser therapy (810 nm) on root development of immature permanent teeth in dogs.

    PubMed

    Fekrazad, Reza; Seraj, Bahman; Ghadimi, Sara; Tamiz, Parvin; Mottahary, Pouriya; Dehghan, Mohammad-Mehdi

    2015-05-01

    Traumatic injuries and dental caries can be a big challenge to immature teeth. In these cases, the main purpose of treatment is to maintain the pulp vitality. The purpose of this study was to investigate the effect of low-level laser therapy on accelerating the rate of dentinogenesis in pulpotomy of immature permanent teeth (apexogenesis). Three dogs, 4-6 months old, were used in this study. One jaw in each dog was randomly assigned to laser irradiation group. All selected teeth were pulpotomized with mineral trioxide aggregate (MTA) and restored with amalgam. In the laser group, the Ga-Al-As laser (810 nm, 0.3 W, 4 J/cm(2), 9 s) was used on buccal and lingual gingiva of each tooth in 48 h intervals for 2 weeks. In order to observe the newly formed dentine, tetracycline was injected on the 1st, 3rd, 7th, and 14th day after the operation. Then, ground sections of teeth were observed under a fluorescence microscope. The data was analyzed with Generalized Estimating Equations (GEE) test. The mean distance between the lines of tetracycline formed on the 1st and 14th day was significantly higher in the laser group (P = 0.005). Within the limitation of this study, irradiation of Ga-Al-As laser (810 nm) can accelerate the rate of dentinogenesis in apexogenesis of immature permanent teeth with MTA in dogs.

  13. Arresting rampant dental caries with silver diamine fluoride in a young teenager suffering from chronic oral graft versus host disease post-bone marrow transplantation: a case report

    PubMed Central

    2014-01-01

    Background Rampant caries is an advanced and severe dental disease that affects multiple teeth. This case describes the management of rampant caries in a young teenager suffering from chronic oral graft versus host disease after allogeneic bone marrow transplantation. Case presentation A 14-year-old Chinese boy suffering from β–thalassemia major was referred to the dental clinic for the management of rampant dental caries. An oral examination revealed pale conjunctiva, bruising of lips, and depapillation of tongue indicating an underlying condition of anemia. The poor oral condition due to topical and systemic immunosuppressants was seriously aggravated, and rampant caries developed rapidly, affecting all newly erupted, permanent teeth. The teeth were hypersensitive and halitosis was apparent. Strategies for oral health education and diet modification were given to the patient. Xylitol chewing gum was used to stimulate saliva flow to promote remineralization of teeth. Silver diamine fluoride was topically applied to arrest rampant caries and to relieve pain from hypersensitivity. Carious teeth with pulpal involvement were endodontically treated. Stainless steel crowns were provided on molars to restore chewing function, and polycarbonate crowns were placed on premolars, upper canines and incisors. Conclusion This case report demonstrates success in treating a young teenager with severe rampant dental decay by contemporary caries control and preventive strategy. PMID:24383434

  14. Alkaline "Permanent" Paper.

    ERIC Educational Resources Information Center

    Pacey, Antony

    1991-01-01

    Discussion of paper manufacturing processes and their effects on library materials focuses on the promotion of alkaline "permanent" paper, with less acid, by Canadian library preservation specialists. Standards for paper acidity are explained; advantages of alkaline paper are described, including decreased manufacturing costs; and recyclability is…

  15. Biocompatibility of a restorative resin-modified glass ionomer cement applied in very deep cavities prepared in human teeth.

    PubMed

    Soares, Diana Gabriela; Basso, Fernanda Gonçalves; Scheffel, Débora Lopes Sales; Giro, Elisa Maria Aparecida; de Souza Costa, Carlos Alberto; Hebling, Josimeri

    2016-01-01

    This study evaluated whether a restorative resin-modified glass ionomer cement, Vitremer (VM), would be biocompatible with pulp tissue when used as a liner in very deep cavities prepared in young human permanent teeth. Two dental cements in current use as liner materials, Vitrebond (VB) and Dycal (DY), were compared to VM. Class V cavities were prepared in 36 sound premolars that were scheduled for extraction, and the cavity floor was lined with the restorative cement (VM) or a liner/base control cement (VB or DY). For VM specimens, the cavity floor was pretreated with a primer (polyacrylic acid plus 2-hydroxyethyl methacrylate). Teeth were extracted after 7 or 30 days and processed for microscopic evaluation. In the VM group, inward diffusion of dental material components through dentinal tubules, associated with disruption of the odontoblastic layer, moderate to intense inflammatory response, and resorption of inner dentin, was observed in 2 teeth at 7 days. These histologic features were observed in 1 tooth at 30 days. In the VB group, mild inflammatory reactions and tissue disorganization observed at 7 days were resolved at 30 days. No pulpal damage occurred in the DY specimens. Of the materials tested, only Vitremer was not considered biocompatible, because it caused persistent pulpal damage when applied in very deep cavities (remaining dentin thickness less than 0.3 mm). PMID:27367631

  16. [Dental anatomy of dogs].

    PubMed

    Sarkisian, E G

    2014-12-01

    The aim of the research was to investigate dog teeth anatomy as animal model for study of etiopathogenesis of caries disease and physiological tooth wear in human. After examining the dog's dental system, following conclusions were drawn: the dog has 42 permanent teeth, which are distributed over the dental arches not equally, and so the upper dentition consists of 20, and the lower of 22 teeth. The largest are considered upper fourth premolar and lower first molars, which are called discordant teeth. Between discordant teeth and fangs a dog has an open bite, which is limited to the top and bottom conical crown premolar teeth. Thus, in the closed position of the jaws, behind this occlusion is limited by discordant teeth, just in contact are smaller in size two molars. Only large dog's molars in a valid comparison can be likened to human molars, which allows us to use them in an analog comparison between them with further study of the morphological features ensure durability short-crown teeth and their predisposition to caries.

  17. Translucency measurements in teeth and dental materials

    NASA Astrophysics Data System (ADS)

    Rawicz, Andrew H.; Melnyk, Ivan; Kowalski, Pawel

    2003-06-01

    Exact color matching of dental restorative materials to vital teeth is a difficult task. There are several reasons for this difficulty and they will be elaborated upon in the presentation. One of the most important reasons is the fact that teeth, as well as dental restorative materials are translucent, and thus the color impression is a product of light scattering, back scattering, transmission, and spectral modifications inside of these objects. Classic colorimetry is insufficient to provide an exact color match. Additional information about the translucency factor of the considered object (material and geometry) is necessary to provide full reproducibility. Translucency has a direct effect on perceived brightness. In this article we describe the TransluDent, a complementary product to ColorDent, which measures translucency of teeth and dental materials. TransluDent determines translucency by measuring light transmitted through an object and light scattered inside of the object. The translucency measurements were performed on two groups of subjects. One group consisted of people in their twenties and the second group of subjects was in fifties. For comparison several sets of dental shade-guides were also tested. The great discrepancy in translucency factor between human teeth and popular on the market shades may explain difficulty in color matching of dental restorative materials to teeth.

  18. Broadening the Scope of Dental Education.

    ERIC Educational Resources Information Center

    Loe, Harald

    1992-01-01

    Scientific and technological advances affecting dental education in the near future are examined, including the growing role of saliva in diagnosis, direct imaging methods, biomaterials research, computer-aided design and manufacturing, molecular biology, and new restorative dentistry. It is argued that dentistry should be a fully recognized…

  19. Dental Assistant.

    ERIC Educational Resources Information Center

    Michigan State Univ., East Lansing. Coll. of Agriculture and Natural Resources Education Inst.

    This curriculum guide, developed for use in dental assistant education programs in Michigan, describes a task-based curriculum that can help a teacher to develop a classroom management system where students learn by doing. It is based on task analysis and reflects the skills, knowledge, and attitudes that employers expect entry-level dental…

  20. Holography And Holometry Applications In Dental Research

    NASA Astrophysics Data System (ADS)

    Willenborg, George C.

    1987-06-01

    The earliest reference to holographic applications appeared in the dental literature in 1972 when Wictorin, Bjelkhagen and Abramson described a method to study elastic deformation of defective gold solder joints in simulated fixed bridges. Their paper, published in the Swedish dental literature, offered a concise presentation of the interferometry technique which led to the development of other research applications of holographic interferometry(holometry) in dentistry. In this presentation, the development and application of the interferometry technique in the dental field will be discussed. Various interesting and potentially useful applications of holography have appeared in the dental literature over the past decade. Some of these, which will be discussed, include the use of holograms as a storage medium for dental study models, multiplexing of computer(CT) scan sections to form white light viewable holograms and the potential application of holographic training aids in the teaching of the basic courses of dental anatomy and restorative dentistry. In addition, some unique related applications will be mentioned including a laser reflection method for accurate non-contact measurement of tooth mobility/movement and a technique for contour mapping of occlusal surfaces to measure wear of restorative materials.

  1. Release and toxicity of dental resin composite

    PubMed Central

    Gupta, Saurabh K.; Saxena, Payal; Pant, Vandana A.; Pant, Aditya B.

    2012-01-01

    Dental resin composite that are tooth-colored materials have been considered as possible substitutes to mercury-containing silver amalgam filling. Despite the fact that dental resin composites have improved their physico-chemical properties, the concern for its intrinsic toxicity remains high. Some components of restorative composite resins are released in the oral environment initially during polymerization reaction and later due to degradation of the material. In vitro and in vivo studies have clearly identified that these components of restorative composite resins are toxic. But there is a large gap between the results published by research laboratories and clinical reports. The objective of this manuscript was to review the literature on release phenomenon as well as in vitro and in vivo toxicity of dental resin composite. Interpretation made from the recent data was also outlined. PMID:23293458

  2. Release and toxicity of dental resin composite.

    PubMed

    Gupta, Saurabh K; Saxena, Payal; Pant, Vandana A; Pant, Aditya B

    2012-09-01

    Dental resin composite that are tooth-colored materials have been considered as possible substitutes to mercury-containing silver amalgam filling. Despite the fact that dental resin composites have improved their physico-chemical properties, the concern for its intrinsic toxicity remains high. Some components of restorative composite resins are released in the oral environment initially during polymerization reaction and later due to degradation of the material. In vitro and in vivo studies have clearly identified that these components of restorative composite resins are toxic. But there is a large gap between the results published by research laboratories and clinical reports. The objective of this manuscript was to review the literature on release phenomenon as well as in vitro and in vivo toxicity of dental resin composite. Interpretation made from the recent data was also outlined.

  3. Access to dental services for head and neck cancer patients.

    PubMed

    Lawrence, Mark; Aleid, Wesam; McKechnie, Alasdair

    2013-07-01

    Dental assessment is important for patients with cancer of the head and neck who are to have radiotherapy, as many of these patients have poor dental health before they start treatment. This, compounded by the fact that radiotherapy to the head and neck has a detrimental effect on oral health, has led the National Institute for Clinical Excellence (NICE) to issue guidance that the dental health of these patients should be assessed before treatment. Unfortunately some multidisciplinary teams, such as the one at United Lincolnshire Hospitals, do not have access to a restorative dentist or a dental hygienist. In a retrospective survey we investigated access to general dental services by patients with head and neck cancer who were to have radiotherapy at our hospital and found that 37/71 (52%) had not been reviewed by a dentist within the past 12 months. A secondary national survey that investigated the availability of restorative dental and dental hygienic services showed that of the 56 multidisciplinary teams that deal with head and neck cancer in England, 19 (34%) do not have access to a restorative dentist and 23 (41%) do not have access to a dental hygienist, suggesting that this problem may be countrywide.

  4. Natural restoration

    SciTech Connect

    Kamlet, K.S.

    1993-02-01

    After a company pays millions of dollars to clean up contaminated site, its liability may not be over. It may have to spend tens of millions more to restore damaged natural resources under an oft-overlooked Superfund program. Examples of liability are cited in this report from the Exxon Valdez oil spill and a pcb leak which contaminated a harbor.

  5. Bilateral agenesis of maxillary permanent canines: Review of the literature

    PubMed Central

    Borzabadi-Farahani, Ali

    2015-01-01

    Oligodontia, or agenesis of six or more teeth, excluding third molars, which involves canine agenesis is rare, and restorative management can be challenging. Bilateral agenesis of a permanent canine in the general population often indicates a several missing adult teeth. The most common sign of it is the primary canine retention beyond its exfoliation age. The multistage restorative management includes the early diagnosis, excluding associated medical problems as well as assessment of patient's malocclusion and facial skeletal pattern, life span of deciduous teeth, possibility of premolar substitution, minimum required number of prosthetic units, patient's preferences, and the cost of treatment. A 10-year-old boy with bilateral agenesis of maxillary permanent canines is described. Some thoughts on the multidisciplinary restorative management of this case are discussed. PMID:25657989

  6. Dental Training Films.

    ERIC Educational Resources Information Center

    Veterans Administration Medical Center, Washington, DC.

    This dental training films catalog is organized into two sections. Section I is a category listing of the films by number and title, indexed according to generalized headings; categories are as follow: anatomy, articulator systems, complete dentures, dental assisting, dental laboratory technology, dental materials, dental office emergencies,…

  7. Variable Permanent Magnet Quadrupole

    SciTech Connect

    Mihara, T.; Iwashita, Y.; Kumada, M.; Spencer, C.M.; /SLAC

    2007-05-23

    A permanent magnet quadrupole (PMQ) is one of the candidates for the final focus lens in a linear collider. An over 120 T/m strong variable permanent magnet quadrupole is achieved by the introduction of saturated iron and a 'double ring structure'. A fabricated PMQ achieved 24 T integrated gradient with 20 mm bore diameter, 100 mm magnet diameter and 20 cm pole length. The strength of the PMQ is adjustable in 1.4 T steps, due to its 'double ring structure': the PMQ is split into two nested rings; the outer ring is sliced along the beam line into four parts and is rotated to change the strength. This paper describes the variable PMQ from fabrication to recent adjustments.

  8. Spectrum of Dental Phenotypes in Nonsyndromic Orofacial Clefting.

    PubMed

    Howe, B J; Cooper, M E; Vieira, A R; Weinberg, S M; Resick, J M; Nidey, N L; Wehby, G L; Marazita, M L; Moreno Uribe, L M

    2015-07-01

    Children with oral clefts show a wide range of dental anomalies, adding complexity to understanding the phenotypic spectrum of orofacial clefting. The evidence is mixed, however, on whether the prevalence of dental anomalies is elevated in unaffected relatives and is mostly based on small samples. In the largest international cohort to date of children with nonsyndromic clefts, their relatives, and controls, this study characterizes the spectrum of cleft-related dental anomalies and evaluates whether families with clefting have a significantly higher risk for such anomalies compared with the general population. A total of 3,811 individuals were included: 660 cases with clefts, 1,922 unaffected relatives, and 1,229 controls. Dental anomalies were identified from in-person dental exams or intraoral photographs, and case-control differences were tested using χ(2) statistics. Cases had higher rates of dental anomalies in the maxillary arch than did controls for primary (21% vs. 4%, P = 3 × 10(-8)) and permanent dentitions (51% vs. 8%, P = 4 × 10(-62)) but not in the mandible. Dental anomalies were more prevalent in cleft lip with cleft palate than other cleft types. More anomalies were seen in the ipsilateral side of the cleft. Agenesis and tooth displacements were the most common dental anomalies found in case probands for primary and permanent dentitions. Compared with controls, unaffected siblings (10% vs. 2%, P = 0.003) and parents (13% vs. 7%, P = 0.001) showed a trend for increased anomalies of the maxillary permanent dentition. Yet, these differences were nonsignificant after multiple-testing correction, suggesting genetic heterogeneity in some families carrying susceptibility to both overt clefts and dental anomalies. Collectively, the findings suggest that most affected families do not have higher genetic risk for dental anomalies than the general population and that the higher prevalence of anomalies in cases is primarily a physical consequence of the

  9. Spectrum of Dental Phenotypes in Nonsyndromic Orofacial Clefting

    PubMed Central

    Howe, B.J.; Cooper, M.E.; Vieira, A.R.; Weinberg, S.M.; Resick, J.M.; Nidey, N.L.; Wehby, G.L.; Marazita, M.L.

    2015-01-01

    Children with oral clefts show a wide range of dental anomalies, adding complexity to understanding the phenotypic spectrum of orofacial clefting. The evidence is mixed, however, on whether the prevalence of dental anomalies is elevated in unaffected relatives and is mostly based on small samples. In the largest international cohort to date of children with nonsyndromic clefts, their relatives, and controls, this study characterizes the spectrum of cleft-related dental anomalies and evaluates whether families with clefting have a significantly higher risk for such anomalies compared with the general population. A total of 3,811 individuals were included: 660 cases with clefts, 1,922 unaffected relatives, and 1,229 controls. Dental anomalies were identified from in-person dental exams or intraoral photographs, and case-control differences were tested using χ2 statistics. Cases had higher rates of dental anomalies in the maxillary arch than did controls for primary (21% vs. 4%, P = 3 × 10−8) and permanent dentitions (51% vs. 8%, P = 4 × 10−62) but not in the mandible. Dental anomalies were more prevalent in cleft lip with cleft palate than other cleft types. More anomalies were seen in the ipsilateral side of the cleft. Agenesis and tooth displacements were the most common dental anomalies found in case probands for primary and permanent dentitions. Compared with controls, unaffected siblings (10% vs. 2%, P = 0.003) and parents (13% vs. 7%, P = 0.001) showed a trend for increased anomalies of the maxillary permanent dentition. Yet, these differences were nonsignificant after multiple-testing correction, suggesting genetic heterogeneity in some families carrying susceptibility to both overt clefts and dental anomalies. Collectively, the findings suggest that most affected families do not have higher genetic risk for dental anomalies than the general population and that the higher prevalence of anomalies in cases is primarily a physical consequence of the cleft

  10. Permanent Peripheral Neuropathy

    PubMed Central

    Higgins, Elizabeth

    2014-01-01

    The health risks and side effects of fluoroquinolone use include the risk of tendon rupture and myasthenia gravis exacerbation, and on August 15, 2013, the Food and Drug Administration updated its warning to include the risk of permanent peripheral neuropathy. We present a case of fluoroquinolone-induced peripheral neuropathy in a patient treated for clinically diagnosed urinary tract infection with ciprofloxacin antibiotic. PMID:26425618

  11. Permanent magnet design methodology

    NASA Technical Reports Server (NTRS)

    Leupold, Herbert A.

    1991-01-01

    Design techniques developed for the exploitation of high energy magnetically rigid materials such as Sm-Co and Nd-Fe-B have resulted in a revolution in kind rather than in degree in the design of a variety of electron guidance structures for ballistic and aerospace applications. Salient examples are listed. Several prototype models were developed. These structures are discussed in some detail: permanent magnet solenoids, transverse field sources, periodic structures, and very high field structures.

  12. Sleep bruxism: review and update for the restorative dentist.

    PubMed

    de-la-Hoz, José L

    2013-01-01

    Sleep bruxism (SB) is a parafunctional oromotor activity that can sometimes pose a threat to the integrity of the structures of the masticatory system if the magnitude and direction of the forces exerted exceed the system's adaptive capacity. Over the years science has tried to provide a consistent explanation of the etiopathogenesis and physiopathology of SB, although the pathophysiological mechanisms are, even now, not fully understood yet. There is at present no specific, effective treatment to permanently eliminate the habit of SB. There are only palliative therapeutic alternatives steered at preventing the pathological effects of SB on the stomatognathic system and alleviating the negative clinical consequences of the habit. The aim of this paper is to review and update the fundamental scientific concepts of SB based on the scientific literature and to furnish an approach to the main types of therapy available, in an attempt to assist the general and restorative dentist to manage those clinical situations in which SB is a significant risk factor for the oral health and/or dental treatment of the patient. PMID:24864394

  13. The use of articulators in UK dental schools.

    PubMed

    Hindle, J R; Craddock, H L

    2006-11-01

    The increasing complexity of many restorative procedures often involves articulation of study and working casts to ensure accurate fabrication of restorations. Correct selection and use of articulators can be crucial to successful restoration. The aim of this paper is to determine which articulators are recommended for various restorative procedures in UK dental schools, for use by undergraduate students. A questionnaire-based study of all UK dental schools was carried out, with a 100% response rate. Recommended articulator application for specified procedures was established from the literature and questionnaire results were compared with this. The results indicated that dental schools in the UK generally teach appropriate articulator use for most procedures. However, there are some limited areas of what may be argued to be inappropriate recommendation in some establishments.

  14. Dental amalgam--environmental aspects

    SciTech Connect

    Arenholt-Bindslev, D. )

    1992-09-01

    Increasing knowledge about the risk of toxic effects caused by anthropogenic mercury accumulation in ecosystems has resulted in a growing pressure for reduction of the discharge of mercury waste. Consequently, the mercury waste problems of dental clinics have been given increased attention, and restrictions on handling and discharge of contaminated waste have been established in several countries. Major amalgam particles from trituration surplus of those produced during the carving and burnishing of new amalgam restorations are generally collected in coarse filters and sold for refinement. Minor amalgam particles released by production of new fillings or by removal of old restorations partly sediment in tubes and drains. The remaining particles are carried with the waste water stream to the local purifying plant. In Scandinavia, the industrial discharge of mercury-contaminated waste water has been reduced to a minimum. According to recent investigations, dental clinics appear to be responsible for the major amount of mercury collected in the sludge generated in purifying plants. If threshold values for heavy metal content, including mercury, are exceeded, the sludge is not allowed to be recycled as fertilizer. Installation of an approved amalgam-separating apparatus in dental clinics is now mandatory in several countries--for example, Switzerland, Germany, Sweden, and Denmark. Approval of amalgam separators is based on national testing programs, including clinical or laboratory tests demanding 95-99% separating efficiency. 18 refs.

  15. Restoring Ancestral Language, Restoring Identity.

    ERIC Educational Resources Information Center

    Bannon, Kay T.

    1999-01-01

    Describes the Cherokee Language Renewal Program that was designed to help Cherokee elementary school children learn to function in the dominant culture without sacrificing their own cultural heritage. Explains how the program got started, and reports on how it helps restore a cultural identify to a people who are at risk of losing their identity.…

  16. Dental Stem Cells and their Applications in Dental Tissue Engineering.

    PubMed

    Lymperi, S; Ligoudistianou, C; Taraslia, V; Kontakiotis, E; Anastasiadou, E

    2013-01-01

    Tooth loss or absence is a common condition that can be caused by various pathological circumstances. The replacement of the missing tooth is important for medical and aesthetic reasons. Recently, scientists focus on tooth tissue engineering, as a potential treatment, beyond the existing prosthetic methods. Tooth engineering is a promising new therapeutic approach that seeks to replace the missing tooth with a bioengineered one or to restore the damaged dental tissue. Its main tool is the stem cells that are seeded on the surface of biomaterials (scaffolds), in order to create a biocomplex. Several populations of mesenchymal stem cells are found in the tooth. These different cell types are categorized according to their location in the tooth and they demonstrate slightly different features. It appears that the dental stem cells isolated from the dental pulp and the periodontal ligament are the most powerful cells for tooth engineering. Additional research needs to be performed in order to address the problem of finding a suitable source of epithelial stem cells, which are important for the regeneration of the enamel. Nevertheless, the results of the existing studies are encouraging and strongly support the belief that tooth engineering can offer hope to people suffering from dental problems or tooth loss.

  17. Dental repair material: a resin-modified glass-ionomer bioactive ionic resin-based composite.

    PubMed

    Croll, Theodore P; Berg, Joel H; Donly, Kevin J

    2015-01-01

    This report documents treatment and repair of three carious teeth that were restored with a new dental repair material that features the characteristics of both resin-modified glass-ionomer restorative cement (RMGI) and resin-based composite (RBC). The restorative products presented are reported by the manufacturer to be the first bioactive dental materials with an ionic resin matrix, a shock-absorbing resin component, and bioactive fillers that mimic the physical and chemical properties of natural teeth. The restorative material and base/liner, which feature three hardening mechanisms, could prove to be a notable advancement in the adhesive dentistry restorative materials continuum.

  18. Dental repair material: a resin-modified glass-ionomer bioactive ionic resin-based composite.

    PubMed

    Croll, Theodore P; Berg, Joel H; Donly, Kevin J

    2015-01-01

    This report documents treatment and repair of three carious teeth that were restored with a new dental repair material that features the characteristics of both resin-modified glass-ionomer restorative cement (RMGI) and resin-based composite (RBC). The restorative products presented are reported by the manufacturer to be the first bioactive dental materials with an ionic resin matrix, a shock-absorbing resin component, and bioactive fillers that mimic the physical and chemical properties of natural teeth. The restorative material and base/liner, which feature three hardening mechanisms, could prove to be a notable advancement in the adhesive dentistry restorative materials continuum. PMID:25822408

  19. Impact of dental therapists on productivity and finances: II. Federally Qualified Health Centers.

    PubMed

    Beazoglou, Tryfon J; Bailit, Howard L; DeVitto, Judy; McGowan, Taegen; Myne-Joslin, Veronica

    2012-08-01

    This article estimates the impact of dental therapists treating children on Federally Qualified Health Center (FQHC) dental clinic finances and productivity. The analysis is based on twelve months of patient visit and financial data from large FQHC dental clinics (multiple delivery sites) in Connecticut and Wisconsin. Assuming dental therapists provide restorative, extraction, and pulpal services and dental hygienists continue to deliver all hygiene services, the maximum reduction in costs is about 6 percent. The limited impact of dental therapists on FQHC dental clinic finances is because 1) dental therapists only account for 17 percent of children services and 2) dentists are responsible for only 25 percent of clinic expenses and cost reductions are related to the difference between dental therapist and dentist wage rates.

  20. Restoration Process

    NASA Technical Reports Server (NTRS)

    1979-01-01

    In the accompanying photos, a laboratory technician is restoring the once-obliterated serial number of a revolver. The four-photo sequence shows the gradual progression from total invisibility to clear readability. The technician is using a new process developed in an applications engineering project conducted by NASA's Lewis Research Center in conjunction with Chicago State University. Serial numbers and other markings are frequently eliminated from metal objects to prevent tracing ownership of guns, motor vehicles, bicycles, cameras, appliances and jewelry. To restore obliterated numbers, crime laboratory investigators most often employ a chemical etching technique. It is effective, but it may cause metal corrosion and it requires extensive preparatory grinding and polishing. The NASA-Chicago State process is advantageous because it can be applied without variation to any kind of metal, it needs no preparatory work and number recovery can be accomplished without corrosive chemicals; the liquid used is water.

  1. Dental practice in Paris.

    PubMed

    Baron, Pierre

    2003-01-01

    This describes dental practice and the availability of dental patent remedies in Paris. Accounts of legal disputes, from original sources, illustrate the status and social history of some of the most wealthy dental practitioners in Paris during the Revolution.

  2. American Dental Association

    MedlinePlus

    ... Public Prevention Summit ADA Find-a-Dentist Health Literacy in Dentistry Volunteer Efforts Dental Benefit Plan Information ... on Sleep Bruxism Rethinking Dental Insurance Oral Health Literacy's Role in Missed Appointments Dental Implant Failure Rate ...

  3. Therapeutic ultrasound for dental tissue repair.

    PubMed

    Scheven, B A A; Shelton, R M; Cooper, P R; Walmsley, A D; Smith, A J

    2009-10-01

    Dental disease affects human health and the quality of life of millions worldwide. Tooth decay (caries) and diseases of the dental pulp result in loss of tooth vitality and function requiring invasive treatment to restore the tooth to health. "Therapeutic" low intensity pulsed ultrasound has been shown to accelerate bone fracture healing indicating that ultrasound may be used as a tool to facilitate hard tissue regeneration. We have shown recently that low frequency ultrasound is able to exert biological effects on odontoblast-like cells. In this paper, we postulate that low frequency, low intensity ultrasound may stimulate endogenous coronal tooth repair by stimulating dentine formation from existing odontoblasts or by activating dental pulp stem cells to differentiate into new reparative dentine-producing cells. Ultrasound therapy promoting dentine formation and repair may also have the potential benefit of alleviating dentine hypersensitivity by inducing occlusion of dentinal tubules. It is envisaged that therapeutic ultrasound may be used in future to facilitate dental tissue engineering and stem cell therapy applications for dental tissue regeneration. Further research is warranted in this clinically important area and we envisage that novel strategies in dental therapy will be realised that may ultimately lead to the development of novel non-invasive, multifunctional ultrasound devices for dental diagnostics, repair and regeneration.

  4. Nanoparticle release from dental composites.

    PubMed

    Van Landuyt, K L; Hellack, B; Van Meerbeek, B; Peumans, M; Hoet, P; Wiemann, M; Kuhlbusch, T A J; Asbach, C

    2014-01-01

    Dental composites typically contain high amounts (up to 60 vol.%) of nanosized filler particles. There is a current concern that dental personnel (and patients) may inhale nanosized dust particles (<100 nm) during abrasive procedures to shape, finish or remove restorations but, so far, whether airborne nanoparticles are released has never been investigated. In this study, composite dust was analyzed in real work conditions. Exposure measurements of dust in a dental clinic revealed high peak concentrations of nanoparticles in the breathing zone of both dentist and patient, especially during aesthetic treatments or treatments of worn teeth with composite build-ups. Further laboratory assessment confirmed that all tested composites released very high concentrations of airborne particles in the nanorange (>10(6)cm(-3)). The median diameter of airborne composite dust varied between 38 and 70 nm. Electron microscopic and energy dispersive X-ray analysis confirmed that the airborne particles originated from the composite, and revealed that the dust particles consisted of filler particles or resin or both. Though composite dust exhibited no significant oxidative reactivity, more toxicological research is needed. To conclude, on manipulation with the bur, dental composites release high concentrations of nanoparticles that may enter deeply into the lungs.

  5. Dental radiology and oral pathology.

    PubMed

    Halstead, C L; Hoard, B C

    1991-01-01

    This article represents an overview of normal and pathological findings of the oral structures for the practicing radiologist. Some of the disease processes discussed are of dental etiology, whereas others are manifestations of systemic diseases. Normal tooth development is described followed by an overview of radiolucent, radiopaque, and mixed lucent-opaque lesions. In the radiolucent category, normal anatomical landmarks of the jaws include the mental foramen, manidbular canal, incisive canal and maxillary sinuses. Other lucencies that represent normal structures or variations include developing tooth buds and root apices, healing dental extraction sites, prominent submandibular fossae and nutrient canals. In the radiopaque category, normal anatomical landmarks of the jaws include the genial tubercle, mental ridge, external oblique ridge, walls of the submandibular canal, walls of the maxillary sinus, nasal septum, stylohyoid ligament, and zygomatic process. Other opacities that represent normal structures or variations include dental restoration material, dental endodontic material, retained roots, sialoliths, salivary duct calculi, calcified lymph nodes, recent extraction sites, hypercementosis, and foreign bodies. Pathological entities which present radiographically as lucencies, opacities, and mixed lucent-opaque areas include inflammatory lesions, cysts, fibro-osseous disease, benign neoplasms, malignant neoplasms, and lesions secondary to metabolic disorders.

  6. Minimally invasive restorative dentistry: a biomimetic approach.

    PubMed

    Malterud, Mark I

    2006-08-01

    When providing dental treatment for a given patient, the practitioner should use a minimally invasive technique that conserves sound tooth structure as a clinical imperative. Biomimetics is a tenet that guides the author's practice and is generally described as the mimicking of natural life. This can be accomplished in many cases using contemporary composite resins and adhesive dental procedures. Both provide clinical benefits and support the biomimetic philosophy for treatment. This article illustrates a minimally invasive approach for the restoration of carious cervical defects created by poor hygiene exacerbated by the presence of orthodontic brackets.

  7. Utilization of ceromer inlays/onlays for replacement of amalgam restorations.

    PubMed

    Koczarski, M J

    1998-05-01

    Fiber-reinforced Ceromer technology has been recommended for a variety of restorations, including inlays/onlays, crowns and bridges, and direct restorations. Ideal restorative dental materials must exhibit adequate physical properties and fit, as well as ease and predictability of fabrication and repair. The Ceromer restorative material combines the positive attributes of indirect composite restorations, feldspathic ceramics, and cast-gold restorations. This article reviews the material properties and aesthetic characteristics inherent to Ceromers, as well as the appropriate preparation and adhesive techniques for inlay/onlay restorations.

  8. Bilateral asymmetry in permanent dentition of 13 pre-conquest samples from Argentina (South America).

    PubMed

    Bollini, G A; Rodríguez-Flórez, C D; Colantonio, S E

    2009-01-01

    Bilateral asymmetry is an important field of study in anthropology. The evaluation of bilateral asymmetry of 44 dental non-metric traits of permanent dentition is carried out in this study on 376 adult skulls from different archaeological sites in Argentina (South America). From a total of 44 traits studied, just 12 (27% of the total traits expressed) presented Bilateral Index (BI) values lower than 100% (between 92% and 99%). Results suggest that the expression of all dental traits is probably bilateral. These results show the importance of analysis of bilateral asymmetry for assignment of taxonomic and population value of non-metric dental traits.

  9. Liquids with permanent porosity.

    PubMed

    Giri, Nicola; Del Pópolo, Mario G; Melaugh, Gavin; Greenaway, Rebecca L; Rätzke, Klaus; Koschine, Tönjes; Pison, Laure; Gomes, Margarida F Costa; Cooper, Andrew I; James, Stuart L

    2015-11-12

    Porous solids such as zeolites and metal-organic frameworks are useful in molecular separation and in catalysis, but their solid nature can impose limitations. For example, liquid solvents, rather than porous solids, are the most mature technology for post-combustion capture of carbon dioxide because liquid circulation systems are more easily retrofitted to existing plants. Solid porous adsorbents offer major benefits, such as lower energy penalties in adsorption-desorption cycles, but they are difficult to implement in conventional flow processes. Materials that combine the properties of fluidity and permanent porosity could therefore offer technological advantages, but permanent porosity is not associated with conventional liquids. Here we report free-flowing liquids whose bulk properties are determined by their permanent porosity. To achieve this, we designed cage molecules that provide a well-defined pore space and that are highly soluble in solvents whose molecules are too large to enter the pores. The concentration of unoccupied cages can thus be around 500 times greater than in other molecular solutions that contain cavities, resulting in a marked change in bulk properties, such as an eightfold increase in the solubility of methane gas. Our results provide the basis for development of a new class of functional porous materials for chemical processes, and we present a one-step, multigram scale-up route for highly soluble 'scrambled' porous cages prepared from a mixture of commercially available reagents. The unifying design principle for these materials is the avoidance of functional groups that can penetrate into the molecular cage cavities. PMID:26560299

  10. Dental students--dental advocates.

    PubMed

    Bensch, Brittany

    2010-01-01

    Student advocacy and involvement in the political process is built into the structure of the American Student Dental Association (ASDA), especially in its Legislative Grassroots Network and an internal communication network among students to ensure political awareness. Students are concerned with such issues as a universally accepted, non-patient-based licensure process, mid-level providers, loan availability and tax deductibility, financial support for schools, and service early in one's professional career (giving forward rather than giving back). Through collaboration with the American Dental Education Association and with many state associations, students participate in lobbying, awareness campaigns, and behind the scenes as legislative aids. Although students share the same love for the profession that animates established practitioners, they are perceived by legislators as being different. Students are involved in the legislative process because it represents their future.

  11. Dental students--dental advocates.

    PubMed

    Bensch, Brittany

    2010-01-01

    Student advocacy and involvement in the political process is built into the structure of the American Student Dental Association (ASDA), especially in its Legislative Grassroots Network and an internal communication network among students to ensure political awareness. Students are concerned with such issues as a universally accepted, non-patient-based licensure process, mid-level providers, loan availability and tax deductibility, financial support for schools, and service early in one's professional career (giving forward rather than giving back). Through collaboration with the American Dental Education Association and with many state associations, students participate in lobbying, awareness campaigns, and behind the scenes as legislative aids. Although students share the same love for the profession that animates established practitioners, they are perceived by legislators as being different. Students are involved in the legislative process because it represents their future. PMID:21314046

  12. Permanent soft tissue fillers.

    PubMed

    Wilson, YuShan L; Ellis, David A F

    2011-12-01

    As our youth-oriented society ages, interest in nonsurgical aesthetic techniques has generated a dramatic rise in the use of filling agents for facial rejuvenation. Backed by multiple published studies documenting safety and efficacy, soft tissue fillers are often viewed as treatments with minimal recovery time and limited risk of complications when compared with traditional surgical interventions. This has led to a genuine demand for fillers with similar safety profiles but ever increasing longevity in their aesthetic corrections. This review addresses many of the permanent soft tissue fillers that are commercially available worldwide as well as important concerns regarding their complications.

  13. Risk factors for dental caries in children with developmental disabilities.

    PubMed

    Braúna, Ana Paula Vasques Sales; Abreu, Mauro Henrique Nogueira Guimarães de; Resende, Vera Lúcia Silva; Castilho, Lia Silva de

    2016-06-14

    The aim of the present study was to investigate risk factors for dental caries in children with developmental disabilities who were treated at a clinical reference service for patients with special needs in Belo Horizonte, MG, Brazil. This is a retrospective cohort study that evaluated 401 dental charts of individuals without dental caries or restorations in their first dental appointment. The dependent variable was the time of occurrence of new dental caries or restorations and was measured in months. Gender, age, International Code of Diseases (ICD), mother´s education, sugar consumption, use of fluoride toothpaste, oral hygiene, mouth breathing, reports of xerostomia, gingival status, use of psychotropic or asthma drugs, and history of asthma were covariates. The Cox proportional hazards regression model was used to estimate the raw and adjusted hazard ratios and their respective 95% confidence intervals. The average time that individuals remained free of dental caries/restoration was equal to 107.46 months (95%CI 95.41 to 119.51), with a median of caries-free children up to 94 months. For each point increase in the scale of sucrose consumption, the increase in caries risk was 1.07 (95%CI 1.01 to 1.15). Sucrose consumption was the only risk factor for dental caries found in this group of individuals with developmental disabilities. PMID:27305514

  14. Developing dental education in primary care: the student perspective.

    PubMed

    Elkind, A; Blinkhorn, A S; Blinkhorn, F A; Duxbury, J T; Hull, P S; Brunton, P A

    2005-02-26

    A pilot outreach course in restorative dentistry based in community clinics began in 2001. As part of the evaluation, 48 fourth year students completed a questionnaire about their opinions of the new course, and about restorative dentistry clinics in the dental hospital. Time management was the most frequently mentioned gain from outreach. In relation to the dental school, students most often saw the specialised teaching staff as a gain. Outreach was equally or more important for students' confidence in clinical diagnosis of dental caries, treatment planning, direct restorations, communicating with patients, and managing patients, time, and resources. The dental hospital was equally or more important for their confidence in the diagnosis of periodontal disease, root planing, crowns, bridges, dentures, and communicating effectively with laboratory staff. Patients in outreach were seen as different from those at the dental hospital because they were unselected, and had different treatment needs. Meeting course requirements was the most frequent concern about outreach. In relation to the dental hospital, students were most often concerned about the quality of teaching and support available. Outreach and the dental hospital provided complementary experiences and the new course met its educational objectives. PMID:15731807

  15. Cryogenic Permanent Magnet Undulators

    SciTech Connect

    Chavanne, J.; Lebec, G.; Penel, C.; Revol, F.; Kitegi, C.

    2010-06-23

    For an in-vacuum undulator operated at small gaps the permanent magnet material needs to be highly resistant to possible electron beam exposure. At room temperature, one generally uses Sm{sub 2}Co{sub 17} or high coercivity NdFeB magnets at the expense of a limited field performance. In a cryogenic permanent magnet undulator (CPMU), at a temperature of around 150 K, any NdFeB grade reveals a coercivity large enough to be radiation resistant. In particular, very high remanence NdFeB material can be used to build undulators with enhanced field and X-ray brilliance at high photon energy provided that the pre-baking of the undulator above 100 deg. C can be eliminated. The ESRF has developed a full scale 2 m long CPMU with a period of 18 mm. This prototype has been in operation on the ID6 test beamline since January 2008. A significant effort was put into the characterization of NdFeB material at low temperature, the development of dedicated magnetic measurement systems and cooling methods. The measured heat budget with beam is found to be larger than expected without compromising the smooth operation of the device. Leading on from this first experience, new CPMUs are currently being considered for the upgrade of the ESRF.

  16. Quality assessment of restorations in a population of school children.

    PubMed Central

    Bagramian, R A; Jenny, J; Woodbury, P J; Proshek, J

    1975-01-01

    An index to measure quality of dental restorative care was devised and utilized on a population of 838 Caucasian school children in a large midwestern city. Quality was measured using a four-point scale. All restorations present were considered as part of the entire mouth. Quality was tested in relation to socioeconomic status. Based on this index the problem of poor quality dental restorations is significant and not necessarily related to socioeconomic status as represented by income or education. Evidence of high quality dentistry as evidenced by stainless steel crowns, space maintainers, and orthodontic appliances was limited to children whose families reported incomes over $6,000. Further use of this quality index is recommended to improve and refine measurements in the area of dental care. PMID:1119639

  17. Esthetic management of anterior dental anomalies: A clinical case.

    PubMed

    Chafaie, Amir

    2016-09-01

    Many types of dental abnormality can be observed in the anterior sectors, where they can cause genuine esthetic problems for our patients. While conventional prosthetic treatments offer the best solutions in terms of esthetic result and durability, they involve the sacrifice of significant quantities of mineralized dental material and cannot be undertaken before the periodontal tissues are mature. Other less invasive alternatives should be envisaged as transitional, or sometimes even permanent, solutions for the management of these anomalies in children and adolescents. This article discusses these options and presents a clinical case where composite resin veneers and microabrasion of the enamel were used to treat dental agenesis and enamel dysplasia.

  18. Lenz microphthalmia syndrome with dental anomalies: a case report.

    PubMed

    Ersin, Nazan Kocatas; Tugsel, Zuhal; Gökce, Bülent; Ozpinar, Birgül; Eronat, Nesrin

    2003-01-01

    This report describes the dental management and 7-year follow-up of a 14-year-old boy who showed the typical characteristics of Lenz microphthalmia syndrome, a rare genetic disorder characterized by multiple abnormalities. The main features of the syndrome are microphthalmia, developmental retardation, ear abnormalities, microcephaly, skeletal, digital and urogenital anomalies. The dental anomalies include micrognathia, hypodontia, agenesis of permanent teeth, conic-shaped incisors, and taurodontic molars. The purpose of the report was to document specific oral manifestations and dental anomalies and their management associated with a previously reported case.

  19. Esthetic management of anterior dental anomalies: A clinical case.

    PubMed

    Chafaie, Amir

    2016-09-01

    Many types of dental abnormality can be observed in the anterior sectors, where they can cause genuine esthetic problems for our patients. While conventional prosthetic treatments offer the best solutions in terms of esthetic result and durability, they involve the sacrifice of significant quantities of mineralized dental material and cannot be undertaken before the periodontal tissues are mature. Other less invasive alternatives should be envisaged as transitional, or sometimes even permanent, solutions for the management of these anomalies in children and adolescents. This article discusses these options and presents a clinical case where composite resin veneers and microabrasion of the enamel were used to treat dental agenesis and enamel dysplasia. PMID:27498052

  20. Choice of a dental implant system.

    PubMed

    Hunt, Peter R; Gartner, Judith L; Norkin, Frederic J

    2005-04-01

    Many dentists are bewildered by the intricacies and complexities of dental implants. They are constantly besieged by product advertisements and can find it difficult to choose which systems to work with. Some dentists are so intimidated by the subject that they choose to avoid getting involved with implants and instead stick to traditional tooth replacement systems. By breaking implants down into 4 main components, the body, collar, connection, and restorative post, it is easier to understand the structure and function of dental implants. Each portion should be designed to achieve certain objectives. Once these structural components are understood, it is easier to compare and contrast differing implant systems.

  1. [Decision-making of restorations for endodontically treated teeth].

    PubMed

    Zhi, Chen; Binwen, Chen

    2015-04-01

    Coronal restoration of endodontically treated teeth may be viewed as one of the main parameters that influence the outcome of endodontic treatment. The purposes of restoring endodontically-treated teeth include preventing recontamination of the root canal system and periapical area, replacing the compromised dental hard tissue, restoring the coronal morphology and function, providing necessary strength for the restoration/tooth complex for functional stress, and avoiding crown and/or root fracture. This article reviewed recent researches on the restoration of endodontically treated teeth, provided evidence for clinical practice on topics as when to restore them, basic principles to be considered during treatment planning, and specific restoration options for both anterior and posterior teeth under different functional occulsal load conditions. Several issues should be taken into account during the decision making process, such as remaining tooth tissue, functional masticatory forces, comprehensive oral rehabilitation, and esthetic requirements.

  2. Dental development and tooth agenesis in children with velocardiofacial syndrome.

    PubMed

    Heliövaara, Arja; Rantanen, Irma; Arte, Sirpa

    2011-11-01

    BACKGROUND. Variations in dental development and tooth agenesis have been reported in children with velocardiofacial syndrome (VCFS). AIM. The aim was to evaluate the dental development and missing permanent teeth in children with VCFS. DESIGN. Forty-five children (23 girls) with VCFS who had visited the cleft palate and craniofacial centre were studied retrospectively from orthopantomograms taken at the mean age of 7.9 years (range 5.8-12.9). Thirteen of the children with VCFS had palatal clefts. The deletion of 22q11 was verified by FISH techniques. The dental stages were assessed by the method of Demirjian, and the dental age was calculated according to the Finnish dental maturity reference values. A paired Student's t-test was used in the statistical analysis. RESULTS. Eight children (17%), four with palatal clefts, had tooth agenesis. Four children (9%) had agenesis of mandibular incisors. The missing teeth (n = 19) were mainly mandibular incisors (n = 6), maxillary lateral incisors (n = 2), and maxillary second premolars (n = 4). The dental age of the children with VCFS was not different from their chronological age, but there was great individual variation. CONCLUSIONS. A high prevalence of missing permanent teeth, especially mandibular incisors, was observed. The need for thorough clinical and radiological dental examination in children with VCFS is emphasized. PMID:21689177

  3. Dental development and tooth agenesis in children with velocardiofacial syndrome.

    PubMed

    Heliövaara, Arja; Rantanen, Irma; Arte, Sirpa

    2011-11-01

    BACKGROUND. Variations in dental development and tooth agenesis have been reported in children with velocardiofacial syndrome (VCFS). AIM. The aim was to evaluate the dental development and missing permanent teeth in children with VCFS. DESIGN. Forty-five children (23 girls) with VCFS who had visited the cleft palate and craniofacial centre were studied retrospectively from orthopantomograms taken at the mean age of 7.9 years (range 5.8-12.9). Thirteen of the children with VCFS had palatal clefts. The deletion of 22q11 was verified by FISH techniques. The dental stages were assessed by the method of Demirjian, and the dental age was calculated according to the Finnish dental maturity reference values. A paired Student's t-test was used in the statistical analysis. RESULTS. Eight children (17%), four with palatal clefts, had tooth agenesis. Four children (9%) had agenesis of mandibular incisors. The missing teeth (n = 19) were mainly mandibular incisors (n = 6), maxillary lateral incisors (n = 2), and maxillary second premolars (n = 4). The dental age of the children with VCFS was not different from their chronological age, but there was great individual variation. CONCLUSIONS. A high prevalence of missing permanent teeth, especially mandibular incisors, was observed. The need for thorough clinical and radiological dental examination in children with VCFS is emphasized.

  4. Are dental indexes useful in sex assessment?

    PubMed

    Acharya, A B; Mainali, S

    2008-12-01

    This study describes sexual dimorphism in dental indexes derived from the permanent dentition. Three dental indices--'crown area,' 'crown module' and 'crown index'--were calculated from the buccolingual (BL) and mesiodistal (MD) measurements of 123 permanent dentitions (58 females and 65 males) belonging to young Nepalese adults (age-range 19-28 years). Sex differences in the dental indexes were assessed using univariate and multivariate statistics and compared to that of linear measurements reported previously on the same sample. Univariate sex dimorphism exhibited by crown area and crown module was similar to that of linear measurements whereas crown index displayed marked variation. The unusual results shown by the latter is explained as the result of it not being a representation of tooth size per se; rather, crown index is an expression of the difference between BL and MD dimensions and may be better suited as an indicator of tooth 'shape'. Stepwise discriminant analyses undertaken for the indices gave moderate to high accuracy rates in sexing (69.8-81.1%). However, this is lower to the classification accuracy reported for linear measurements. Therefore, it is concluded that dental indexes have no added utility in forensic sex assessment.

  5. Restorative dentistry for the pediatric patient.

    PubMed

    Hackmyer, Steven P; Donly, Kevin J

    2010-11-01

    The American Academy of Pediatric Dentistry sponsored the Pediatric Restorative Dentistry Consensus Conference in 2002. This paper will review the consensus statements that were issued as a result of the conference. Since the conference there have been advances in procedures, materials, and techniques that need to be considered in terms of some of the consensus statements. The introduction of the First Dental Home, interim therapeutic restoration and nanotechnology are examples of some of the materials and techniques that are now part of everyday pediatric dentistry. This paper will discuss the updates as it relates to each of the 2002 consensus statements.

  6. Combined technique with glass-fibre-reinforced composite post and original fragment in restoration of traumatized anterior teeth--a case report.

    PubMed

    Altun, Ceyhan; Guven, Gunseli

    2008-12-01

    Dentoalveolar trauma is frequently encountered by dental practitioners. In some instances, saving a child's traumatized permanent teeth can create difficulties for the child, the parents and the dentist. Reattachment of a crown fragment is a conservative treatment that should be considered for crown fractures of anterior teeth. This case describes the clinical reattachment of an original tooth fragment. A 10-year-old male presented at the Department of Pediatric Dentistry with a complex crown fracture of the left maxillary central incisor 1 day after the trauma occurred. Following endodontic treatment, a glass-fibre-reinforced composite root canal post (FRC Postec; Ivoclar Vivadent AG, Schaan, Liechtenstein) was inserted to increase retention and distribute stress along the root. The dental restoration was completed using the original fragment and a dual-cured resin composite (Variolink II; Ivoclar Vivadent AG). Clinical and radiographic examinations at 1-year recall showed the glass-fibre-reinforced composite root canal post and restoration to be in place, indicating the success of the treatment in maintaining the fractured tooth. Thus, we conclude that reattachment of a tooth fragment using a dual-cured resin composite and a glass-fibre-reinforced composite root canal post is an alternative method for the rehabilitation of fractured teeth that offers satisfactory aesthetic and functional outcomes.

  7. Weaker dental enamel explains dental decay.

    PubMed

    Vieira, Alexandre R; Gibson, Carolyn W; Deeley, Kathleen; Xue, Hui; Li, Yong

    2015-01-01

    Dental caries continues to be the most prevalent bacteria-mediated non-contagious disease of humankind. Dental professionals assert the disease can be explained by poor oral hygiene and a diet rich in sugars but this does not account for caries free individuals exposed to the same risk factors. In order to test the hypothesis that amount of amelogenin during enamel development can influence caries susceptibility, we generated multiple strains of mice with varying levels of available amelogenin during dental development. Mechanical tests showed that dental enamel developed with less amelogenin is "weaker" while the dental enamel of animals over-expressing amelogenin appears to be more resistant to acid dissolution.

  8. Dental education in Colombia

    PubMed Central

    Jaramillo, Jorge A.; Pulido, Jairo H. Ternera; Núñez, Jaime A. Castro; Bird, William F.; Komabayashi, Takashi

    2014-01-01

    This article describes Colombia's development of formal dentistry, its dental school system, curriculum, and dental licensure, and current issues in oral health care. In 1969, there were only 4 dental schools in Colombia; at this writing there are 21. Five dental schools are public and the other 16 are private. Nearly all classes are conducted in Spanish. Undergraduate pre-dental coursework is not a prerequisite for dental school in Colombia. To obtain licensure, Colombian dental students must complete 5 years of study in dental school, earn a diploma, and work for the government for 1 year. There are approximately 41,400 dentists in Colombia, and the number is increasing quickly. However, the unemployment rate among dentists is very high, even though graduation from dental school is extremely difficult. Although the 1,100:1 ratio of citizens to dentists is considered satisfactory, access to dental care is limited due to the high rate of poverty. PMID:20339245

  9. Applications of Light Amplification by Stimulated Emission of Radiation (Lasers) for Restorative Dentistry.

    PubMed

    Najeeb, Shariq; Khurshid, Zohaib; Zafar, Muhammad Sohail; Ajlal, Syed

    2016-01-01

    Light amplification by stimulated emission of radiation (laser) has been used widely in a range of biomedical and dental applications in recent years. In the field of restorative dentistry, various kinds of lasers have been developed for diagnostic (e.g. caries detection) and operative applications (e.g. tooth ablation, cavity preparation, restorations, bleaching). The main benefits for laser applications are patient comfort, pain relief and better results for specific applications. Major concerns for using dental lasers frequently are high cost, need for specialized training and sensitivity of the technique, thereby compromising its usefulness particularly in developing countries. The main aim of this paper is to evaluate and summarize the applications of lasers in restorative dentistry, including a comparison of the applications of lasers for major restorative dental procedures and conventional clinical approaches. A remarkable increase in the use of lasers for dental application is expected in the near future. PMID:26642047

  10. Dental impressions using 3D digital scanners: virtual becomes reality.

    PubMed

    Birnbaum, Nathan S; Aaronson, Heidi B

    2008-10-01

    The technologies that have made the use of three-dimensional (3D) digital scanners an integral part of many industries for decades have been improved and refined for application to dentistry. Since the introduction of the first dental impressioning digital scanner in the 1980s, development engineers at a number of companies have enhanced the technologies and created in-office scanners that are increasingly user-friendly and able to produce precisely fitting dental restorations. These systems are capable of capturing 3D virtual images of tooth preparations, from which restorations may be fabricated directly (ie, CAD/CAM systems) or fabricated indirectly (ie, dedicated impression scanning systems for the creation of accurate master models). The use of these products is increasing rapidly around the world and presents a paradigm shift in the way in which dental impressions are made. Several of the leading 3D dental digital scanning systems are presented and discussed in this article.

  11. Atypical Forensic Dental Identifications.

    PubMed

    Cardoza, Anthony R; Wood, James D

    2015-06-01

    Forensic dental identification specialists are typically the last conventional option for postmortem identification. Forensic dental identification is most often accomplished by comparing radiographs of the decedent's teeth with the dental radiographs obtained from the dentist of the suspected victim. Unfortunately, antemortem dental radiographs are not always available. When presented with this challenge, the authors of this article have been successful in completing identifications using means other than dental radiographic comparison. PMID:26126345

  12. Atypical Forensic Dental Identifications.

    PubMed

    Cardoza, Anthony R; Wood, James D

    2015-06-01

    Forensic dental identification specialists are typically the last conventional option for postmortem identification. Forensic dental identification is most often accomplished by comparing radiographs of the decedent's teeth with the dental radiographs obtained from the dentist of the suspected victim. Unfortunately, antemortem dental radiographs are not always available. When presented with this challenge, the authors of this article have been successful in completing identifications using means other than dental radiographic comparison.

  13. Achieving permanency for LGBTQ youth.

    PubMed

    Jacobs, Jill; Freundlich, Madelyn

    2006-01-01

    This article brings together two significant efforts in the child welfare field: achieving permanence for youth in out-of-home care and meeting the needs of lesbian, gay, bisexual, transgender and questioning (LGBTQ) youth. During the past several years, a national movement has taken place to assure all children and youth have a permanent family connection before leaving the child welfare system; however, LGBTQ youth are not routinely included in the permanency discussions. At the same time, efforts in addressing the needs of LGBTQ youth have increased, but permanency is rarely mentioned as a need. This article offers models of permanence and practices to facilitate permanence with LGBTQ youth and their families. It also offers a youth-driven, individualized process, using youth development principles to achieve relational, physical, and legal permanence. Reunification efforts are discussed, including services, supports, and education required for youth to return to their family of origin. For those who cannot return home, other family resources are explored. The article also discusses cultural issues as they affect permanence for LGBTQ youth, and, finally, addresses the need for ongoing support services to sustain and support permanency.

  14. Expansion of a Predoctoral Surgical Implant Selective for Dental Students.

    PubMed

    Seitz, Stefanie D; Zimmermann, Richard L; Hendricson, William D

    2016-03-01

    Historically, predoctoral dental education programs have focused on the restoration of implants in the clinical environment; however, given the increase in dental implant therapy being performed by general dentists, the need to incorporate surgical implant training is becoming evident. This article describes a predoctoral surgical implant selective at the University of Texas Health Science Center at San Antonio and its evolution across five years to include emerging techniques and technology to enhance students' understanding of dental implant therapy, both surgical and restorative. From virtual implant planning and guided surgery to intra-oral scanning of implants for custom abutments and restorations, students obtained first-hand experiences with a wide spectrum of aspects of implant therapy. The results of anonymous surveys completed by 2014-15 students before and after the year-long selective regarding their impression of the program are also discussed. PMID:26933108

  15. Subsurface damage induced in dental resurfacing of a feldspar porcelain with coarse diamond burs.

    PubMed

    Song, Xiao-Fei; Yin, Ling

    2009-02-01

    The primary cause for early failure of ceramic restorations is surface and subsurface damage induced in adjustment and resurfacing using dental handpieces/burs. This paper reports finite element analysis (FEA) modelling of dental resurfacing to predict the degrees of subsurface damage, in combination with experimental measurement using scanning electron microscopy (SEM). The FEA predictions of subsurface damage induced in a feldspar porcelain with coarse diamond burs were in agreement with the SEM experimental measurement. These findings provide dental clinicians a quantitative description of the response of dental resurfacing-induced subsurface damage. The implication of the results for non-destructive evaluation of subsurface damage by FEA modelling will be practically meaningful to clinical dental restorations for high-quality ceramic restorations. PMID:19144338

  16. Three-dimensional imaging and guided surgery for dental implants.

    PubMed

    Ganz, Scott D

    2015-04-01

    Clinicians worldwide are increasingly adopting guided surgical applications for dental implants. Clinicians are becoming more aware of the benefits of proper planning through advanced imaging modalities and interactive treatment planning applications. All aspects of the planning phase are based on sound surgical and restorative fundamentals. As an integral part of the implant team, dental laboratories have now moved from analog to the digital world, providing the necessary support to the new digital workflow.

  17. How effective is ART in the management of dental caries?

    PubMed

    Frencken, J E; Holmgren, C J

    1999-12-01

    The ART approach involves excavating cavitated dentine caries with hand instruments, then restoring the cavity and sealing any associated fissures and pits with an adhesive restorative material, resulting in a sealant restoration. Until recently, ART has mainly been used under field conditions, and thus the adhesive restorative material used has been glass ionomer which does not require mixing machines and curing lights. Since the inception of ART, a growing number of studies world-wide have taken place. A total of four studies have reported 3-year survival percentages for one-surface ART restorations. The highest 3-year survival percentage in permanent teeth was 88%, which is comparable to the 85% survival of one-surface amalgam restorations placed under the same field conditions after 3 years. The outcomes depend to some extent on the material used, operator experience and presence of caries. The presence of caries as a reason for failure was higher in the early than in the most recent studies. Only one study has reported on the use of ART restorations in the deciduous dentition. It is concluded that: a very large proportion of dentine lesions in the permanent teeth can be treated using the ART approach; the 3-year survival rate of the more recently placed one-surface ART restorations in permanent teeth was higher than that of ART restorations placed in the beginning; the survival of one-surface ART restorations in the permanent dentition with newer glass ionomers is comparable to that of one-surface conventional restorations placed using amalgam in a comparable setting after 3 years; more studies of longer duration are needed to confirm these findings; ART should be considered a caries treatment modality that benefits people; and educational courses need to be organised before the approach is applied in the clinic. PMID:10600076

  18. A case report of green pigmentation in the permanent dentition.

    PubMed

    Chambers, Colin P; O'Morain, Donnchadh; Keightley, Alexander; Welbury, Richard R

    2012-01-01

    Intrinsic green discoloration of teeth is an uncommon condition which mainly affects the primary dentition. Children can be teased about this, resulting in a loss of self-esteem and problems with social integration. The purpose of this paper was to present a case of green pigmentation in the permanent dentition caused by hyperbilirubinemia during infancy and an intermediate restorative approach to mask the esthetic deficiency arising from this. PMID:23433625

  19. Dental hyponatraemia.

    PubMed

    Simpson, R M

    2011-08-01

    A 14-year-old girl developed dental pain and was treated for acute infected pulpitis of her right upper lateral incisor with drilling and filling. The pain continued and was helped by analgesia, sucking ice cubes and drinking cold water. Forty-eight hours later, she became confused and disoriented. She started to vomit and complained of headache. Investigations revealed hyponatraemia with normal serum potassium levels and initially normal urinary sodium excretion. Over the next 24 hours, she passed 5.45 L of urine and her serum sodium rose from 125 to 143 mmol/L. Self-induced water intoxication has been described during drinking games and initiation ceremonies, but this would appear to an unusual cause. Conservative management proved successful in allowing this girl to recover without sequelae. PMID:21873727

  20. [The stamp technique for direct composite restoration].

    PubMed

    Perrin, Philippe; Zimmerli, Brigitte; Jacky, Daniel; Lussi, Adrian; Helbling, Christoph; Ramseyer, Simon

    2013-01-01

    The indications for direct resin composite restorations are nowadays extended due to the development of modern resin materials with improved material properties. However, there are still some difficulties regarding handling of resin composite material, especially in large restorations. The reconstruction of a functional and individual occlusion is difficult to achieve with direct application techniques. The aim of the present publication was to introduce a new "stamp"-technique for placing large composite restorations. The procedure of this "stamp"-technique is presented by three typical indications: large single-tooth restoration, occlusal rehabilitation of a compromised occlusal surface due to erosions and direct fibre-reinforced fixed partial denture. A step-by-step description of the technique and clinical figures illustrates the method. Large single-tooth restorations can be built-up with individual, two- piece silicone stamps. Large occlusal abrasive and/or erosive defects can be restored by copying the wax-up from the dental technician using the "stamp"-technique. Even fiber-reinforced resin-bonded fixed partial dentures can be formed with this intraoral technique with more precision and within a shorter treatment time. The presented "stamp"-technique facilitates the placement of large restoration with composite and can be recommended for the clinical use.