Fracture strength of veneer contact lens

The no prep technique to ceramic veneer have some advantages, one of the most important is the preservation of tooth structure. Purpose: Evaluate fracture resistance in bovine teeth, of ceramic veneer in different thickness (0,3 to 1,0mm). Methods: 60 teeth were selected for this study. Forty fifth ceramic veneer were made for each tooth, variating the thickness in: G1 ­ 0,7mm; G2 ­ 0,5mm; G3 ­ 0,3mm and G4 ­ 1,0mm (control group). Flexural strength test was carried out after 24h of luting. The results were analysed by ANOVA and HSD of Tukey. Results: the results showed that was no statistic difference between the groups (G1- 297.2200; G2 - 294.5467; G3 - 291.9380 and G4 -290.0733). Conclusion: The ceramic veneer thickness didn't have influence in the final flexural strength.

Restabelecimento estético em dentes anteriores com resina composta ou laminados cerâmicos / Aesthetic restoration in anterior teeth using composite resins or ultra-thin veneers

Atualmente existem diferentes alternativas para solucionar de forma conservadora alterações estéticas em dentes anteriores. Entre elas se podem destacar as facetas confeccionadas pela técnica direta (resina composta) ou indireta (cerâmica). Cada material apresenta vantagens e desvantagens, o que faz com que muitos cirurgiões-dentistas tenham dúvidas com relação à melhor opção de tratamento. O objetivo deste trabalho é apresentar dois casos clínicos de pacientes insatisfeitos com a estética de seu sorriso, em que se optou por realizar um com resina composta e o outro com laminados cerâmicos. Conclui-se que é possível atingir a excelência em estética com ambos os materiais. O fundamental para isso é um bom planejamento inicial do caso, para que se defina a melhor indicação para cada paciente, de acordo com suas particularidades...

A number of alternatives are available today to solve conservatively the aesthetic changes in anterior teeth. Among them, composite resin (direct technique) or ceramic (indirect) veneers may be highlighted. Each material presents advantages and disadvantages, which makes many dentists to have questions regarding the best treatment option. The aim of this study is to present two clinical cases where patients unsatisfied with the aesthetics of their smile, which were treated with composite resin and the other with ceramic veneers. It was concluded that it is possible to achieve excellence in aesthetics with both materials. A good initial planning of the case is paramount to define the best indication for each patient within their particularities...

Should acid etching be performed prior to nonvital bleaching?

This study sought to measure the microtensile bond strength of a nanofilled composite resin to human dentin after phosphoric acid etching followed by nonvital bleaching. Scanning electron microscopy was used to analyze fracture modes. Twenty extracted sound human maxillary premolars were prepared for Class I defects and assigned randomly to 4 groups (n = 5): Group 1 (control group) samples were unbleached and had no previous acid etching; Group 2 samples were bleached only, Group 3 samples were acid-etched for 15 seconds prior to bleaching, and Group 4 samples were acid-etched for 30 seconds prior to bleaching. There were no statistically significant differences of bond strength values among Groups 1-3; however, the mean values of Group 4 were statistically lower compared with the other groups.

Effect of dental bleaching on the microleakage of class V composite restorations / Efeito do clareamento dental na microinfiltração em restaurações classe V de resina composta

Purpose: The purpose of this study was to evaluate the effect of bleaching agents on the microleakage of Class V composite restorations. Methods: Class V cavities were prepared on the buccal surface of 30 bovine incisors with the incisal margin located in enamel and the gingival margin located in dentin. The cavities were restored using the adhesive system Adper SingleBond2 and the composite Filtek Z250. After 24 h, the samples were finished, polished, thermocycled (500 cycles), and randomly divided into three groups (n=10): (G1) bleached with 35% Hydrogen Peroxide, (G2) bleached with 10% Carbamide Peroxide, and (G3) control group. After bleaching, the samples were coated with wax and nail polish varnish, immersed in 0.5% basic fuchsin for 24 h, and cut parallel to the long axis of the tooth at three reference points on the restoration. The slices were photographed to evaluate the dye penetration and scored for microleakage. Data were analyzed by Kruskal-Wallis test. Results: Microleakage was absent in more than 90% and 53% of the margins located in enamel and dentin, respectively. No significant difference in microleakage was found between control and experimental groups. Conclusion: The bleaching agents tested had no effect on microleakage at the adhesive interface in enamel or dentin.

Objetivo: Avaliar os efeitos dos agentes clareadores na microinfiltração em restaurações Classe V de resina composta. Metodologia: Foram preparadas 30 cavidades classe V na face vestibular de incisivos bovinos com a margem incisal localizada em esmalte e a gengival em dentina. As cavidades foram restauradas com o sistema adesivo Adper Single-Bond e resina composta Filtek Z250. Após 24 horas realizou-se o acabamento, polimento e 500 ciclos de termociclagem. Os dentes foram divididos aleatoriamente em 3 grupos (n=10). (G1) clareados com Peróxido de Hidrogênio 35%; (G2) clareados com Peróxido de Carbamida 10%; e (G3) controle. Os espécimes foram recobertos com cera e esmalte de unha e imersos em fucsina básica 0,5% por 24 horas. Transcorrido esse período, as amostras foram seccionados no longo eixo do dente em três pontos da restauração e as fatias fotografadas para analisar a microinfiltração do corante. Os dados (escore) foram analisados por teste de Kruskal-Wallis. Resultados: Mais de 90% e 53% das margens localizadas em esmalte e dentina, respectivamente, não apresentaram microinfiltração. Não houve diferença estatística na microinfiltração dos grupos testados em comparação com o grupo controle. Conclusão: Os agentes clareadores testados não afetaram a microinfiltração na interface adesiva em esmalte e dentina.

Microtensile bond strength of a nanofilled composite resin to human dentin after nonvital tooth bleaching.

PURPOSE: The purpose of this in vitro study was to measure the microtensile bond strength of a nanofilled composite resin to human dentin after nonvital bleaching at different post-bleaching time intervals, and to analyze the fracture mode under SEM. MATERIALS AND METHODS: Thirty-six sound human maxillary premolars extracted for orthodontic reasons were prepared in a standardized manner, and randomly assigned to four groups (n = 9): non bleached (control) (NB); bleached with sodium perborate and 35% hydrogen peroxide (SP-HP); bleached with 35% hydrogen peroxide (HP); and bleached with 37% carbamide peroxide (CP). Each group was subdivided into 3 subgroups (n = 3): restored immediately (RO); restored after 7 days (R7); and restored after 14 days (R14). The teeth were stored in distilled water for 24 h, sectioned 4 mm below cementoenamel junction, and the crown was serially sectioned to obtain sticks (0.9 mm2 cross section) for microtensile bond strength testing. The microTBS samples were attached to a universal testing machine (Instron, model 4444), using a Geraldeli's device. The test was performed until the fracture of the specimens, and all specimens were analyzed under a scanning electron microscope (Philips XL-30). RESULTS: Two-way ANOVA (p = 0.05) revealed that there were no statistically significant differences of bond strength values for the bleaching agents used, or at different post-bleaching time intervals. CONCLUSION: It was concluded that the definitive restoration can be accomplished immediately after nonvital bleaching treatment.

Influence of the duration of treatment using a 10% carbamide peroxide bleaching gel on dentin surface microhardness: an in situ study.

This in situ study evaluated the influence of two home-use tooth bleaching regimes (1 hour/day and 7 hours/day) using 10% carbamide peroxide (Nite White Excel 2Z) on the surface microhardness of dentin over a 21-day period. Nine blocks of dentin derived from the teeth of subjects, each with at least two thirds molar in need of extraction, were obtained from the cervical region and submitted to surface-hardness analysis (Shimadsu HMV/2000), fixed to an intraoral palate device fabricated for each subject, and positioned (3 left side, 3 right side, 3 center) according to experimental group. During the bleaching period, casts bearing the whitening agent were applied to the blocks for 7, 1, and 0 hours, respectively (7 left side, 3 right side, 0 center). After the treatment period, the specimens were once again submitted to microhardness analysis, using the same equipment as before, and then analysis of variance and the Scheffé test were applied to the mean differences between the initial and final evaluations. The results demonstrated that the statistical difference between the 1-hour and 7-hour groups was not significant. However, the 7-hour group, when compared with the control group, demonstrated statistically significant differences with a reduction in microhardness. Despite the occurrence of mineral loss in the 1-hour and 7-hour groups, this difference was only 3.1% and 5.4%, respectively, which allows one to conclude that these values probably have no clinical significance.

Onlay cerâmico: relato de um caso clínico / Ceramics onlay: a case report

É cada vez maior o número de pessoas que solicitam restaurações estéticas nos dentes posteriores. Todavia, nenhum material é capaz de substituir com perfeita integridade a estrutura dental perdida. As resinas compostas de uso direto apresentam vários problemas, como contração de polimerização, microinfil-tração, sensibilidade pós-operatória, entre outros. Com o intuito de superar essas dificuldades, novos sistemas cerâmicos tem sido desenvolvidos e tornaram-se opções estéticas de alta qualidade. O objetivo deste artigo é apresentar um protocolo clínico passo a passo para a execução de um onlay cerâmico com o sistema IPS Empress.

Contemporary trends and techniques in tooth whitening: a review.

UNLABELLED: The popularity of tooth whitening has increased with the advent of patient-applied, peroxide-based whitening agents, as well as increased media influence. Peroxides are considered effective and safe when used under professional supervision. Whitening methods include those prescribed by a dental professional for the patient's at-home use, those applied by the dental professional in the office, a combination of both, or methods available over the counter (OTC). This article reviews the effect of contemporary whitening agents and illustrates the clinical application of three methods prescribed by dental professionals. LEARNING OBJECTIVES: This article presents the use of three different types of whitening agents for improved aesthetics. Upon reading this article, the reader should be able to: Distinguish the difference between professionally administered in-office and at-home tooth-whitening results. Identify the effects of whitening agents on dental tissues.

Resistência de uniäo de sistemas adesivos de frasco único / Shear bond strength of one-bottle adhesive systems

O presente trabalho tem por intençäo avaliar a resistência de uniäo ao esmalte e à dentina de quatro novos sistemas adesivos de frasco único: Bond 1, (Jeneric/Pentron); One Coat Bond (Coltene/Whaledent; Prime&Bond NT, (Dentsply); PermaQuick 1, (Ultradent). Verificou-se que a força de uniäo ao esmalte ainda é superior à dentina, mesmo com os sistemas de última geraçäo. Comparando-se os resultados obtidos nos 4 diferentes sistemas, constatou-se que, em esmalte, todos os agentes tiveram resultados equivalentes. Entretanto, no substrato dentinário, o sistema One Coat Bond apresentou resistência de uniäo significantemente maior que o sistema Bond 1

Restauraçöes cerâmicas estéticas e próteses livres de metal: as novas alternativas possibilitadas pelas novas porcelanas / Ceramic restorations and metal-free prostheses: the new alternatives with the new porcelains

Este artigo visa desmistificar e classificar de forma objetiva os sistemas cerâmicos utilizados em restauraçöes livres de metal. Cada sistema é mencionado de forma objetiva e sumarizada, onde procura-se abordar suas principais características, vantagens e desvantagens, propiciando com isso uma facilitada seleçäo e uso por parte do profissional. Dois casos clínicos (IPS Empress 2) säo mostrados de forma inicial e final para demonstrar o potencial estético e de resistência do sistema

Reimplante intencional para tratamento de perfuraçäo radicular / Intentional replantation for the root perforation treatment

Com a finalidade de superar as dificuldades associadas ao tratamento de perfuraçöes radiculares, este trabalho se propôe a apresentar uma nova proposta terapêutica, visando obter o acesso necessário à terapia adequada. Será descrito um caso clínico de perfuraçäo a nível de terço médio radicular, onde o tratamento convencional era inviável. Optou-se pela realizaçäo do Reimplante Intencional, escolhendo o MTA (Agregado de Trióxido Mineral) como material de preenchimento, que as pesquisas têm demonstrado ser um excelente material para essa finalidade

The use of natural teeth to make removable partial prostheses and complete prostheses: case reports / O uso de dentes naturais na confecção de próteses parciais e próteses completas: relato de caso

Human natural teeth were used in manufacturing two complete prostheses and two partial removable dentures in three patients. All four prostheses continue to function satisfactorily. The practitioner, by utilizing the patient's natural teeth in preference to artificial teeth, achieves an excellent means of solving the patient's esthetic problems

Dupla moldagem: registro oclusal / Double impression for occlusal registration

Este trabalho apresenta duas técnicas de moldagem onde os hemi-arcos superior e inferior são moldados simultaneamente, ao mesmo tempo em que o registro inter-oclusal é realizado. A primeira técnica utiliza uma moldeira plástica descartável (Triple-Tray Premier) com material de moldagem Impregum (Espe/Premier), um poliéter, e na confecção dos modelos se confecciona um "oclusor", dispensando o uso do articulador. A segunda técnica utiliza uma moldeira metálica que se acopla a um articulador do tipo semi-ajustável (Gama II), empregando como material de moldagem uma silicona de adição, no caso o Provil. As duas técnicas racionalizam o procedimento da moldagem reduzindo o tempo de trabalho, economizando material de moldagem e a realização de um registro inter-oclusal precisão

Reparos em restaurações de amálgama / Repairs in amalgam restorations

Os autores relatam os principais estudos realizados recentemente sobre a reparação das restaurações de amálgama

Composite resin veneers: a new technique / Resina composta compensada: uma nova técnica

A new technique for the fabrication of composite resin direct veneers is presented. In this technique, a transparent acrylic resin matrix is fabricated before preparation of the facial surface of the tooth, to allow the adequate reproduction of contour, shape, and surface texture originally exhibited by the tooth. Advantages, as well as limitations, of the procedure are also presented

Facetas estéticas com resinas compostas / Esthetics with laminate veneers with composite resins

Os autores descrevem uma técnica direta para confecção de facetas estéticas com resinas compostas, que o profissional pode realizar no consultório sem necessidade de etapas laboratoriais

Estágio atual da técnica do sanduiche: restaurações de ionômero de vidro + resina composta / Sandwich technique (glass ionomer plus composite resins)

As restaurações que envolvem o uso dos cimentos de ionômero de vidro associados às resinas compostas (restaurações sanduíche), mesmo possuidoras de certas desvantagens que dificultam sua praticidade, ainda se apresenta como a melhor para bloquear a infiltração marginal em cavidades onde inexiste esmalte na margem cervical ou quando esta for de pobre qualidade, representando a médio e longo prazo um benefício para a restauração

Osteomielite de Garré de mandíbula: regressão após terapia endodôntica / Garré's osteomyelitis of the mandible: resorption after endodontic therapy

Este artigo relata um caso de osteomielite de Garré de mandíbula, em paciente do sexo feminino, cor branca, com 19 anos, apresentando as características clínicas e radiográficas. Após eliminada a infecção dental por tratamento endodôntico ocorreu regressão da lesão