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A evolução dos materiais restauradores e a redução em tamanho dos preparos cavitários não vem sendo acompanhadas por mudanças no ensino da Dentística Restauradora. Materiais adesivos e a utilização do flúor fazem com que os preparos cavitários sejam cada vez menos invasivos e mais conservadores. Este artigo tem por objetivo propor uma nova metodologia pedagógica para o início do ensino da Dentística Restauradora. Através desta prática os alunos poderão adquirir um maior controle manual com a alta rotação evitando o desgaste desnecessário e preservando o elemento dental (AU).

The evolution of restorative materials and the reduction in cavity preparation size are not being followed by changes in operative dentistry education. Adhesive materials and fluorine usage make cavity preparation less invasive and more conservative. This article has the purpose of showing a new teaching methodology for the early stages of operative dentistry education. Through this practice, students will be able to acquire better manual control with highspeed handpieces to avoid unnecessary eroding and to preserve dental tissue (AU).

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AIM: The aim of this study was to investigate the influence of light curing method, composite shade, and depth of cure on composite microhardness. METHODS AND MATERIALS: Forty-eight specimens with 4 mm of depth were prepared with a hybrid composite (Filtek Z-100, 3M ESPE); 24 with shade A1 and the remaining with shade C2. For each shade, two light curing units (LCUs) were used: a quartz-tungsten-halogen (QTH) LCU (Optilight Plus - Gnatus) and a light emitting diode (LED) LCU (LEC 470 II - MM Optics). The LED LCU was tested using two exposure times (LED 40 seconds and LED 60 seconds). After 24-hour storage, three indentations were made at mm depth intervals using a Knoop indenter. Data were submitted to three-way analysis of variance (ANOVA) and Tukey's test (p<0.05). RESULTS: The three factors tested (light curing method, shade, and depth) had a significant influence on the composite microhardness (p<0.05). All groups presented similar hardness values in the first mm, except for composite shade C2 cured with LED for 40 seconds. The hardness decreased with depth, especially for shade C2 for 40 seconds. Increasing light-curing time with LED produced hardness values similar to the QTH. CONCLUSIONS: The light curing method including variations of time, the depth of cure, and the composite shade influence the composite microhardness. CLINICAL SIGNIFICANCE: Clinicians should avoid thicker increments when working with composite restorations. Extended light-curing time might be indicated depending on the composite shade and on the light-curing device.

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Os objetivos deste estudo foram avaliar a resistência de união de dois sistemas adesivos autocondicionantes em dentina bovina e discutir alguns conceitos que envolvem os adesivos contemporâneos e os ensaios de resistência de união. Incisivos bovinos foram preparados com auxílio de lixas de carbeto de silício até a obtenção de superfícies planas de dentina média (60 mm2). Os adesivos Clearfil SE Bond (Kuraray) e Clearfil S3 Bond (Kuraray) foram aplicados, e matrizes Tygon foram posicionadas sobre cada amostra de dentina hibridizada, sendo preenchidas em seu volume interno com o cimento resinoso RelyX ARC (3M Espe). Após fotoativação, removeram-se as matrizes e expurseram-se os corpos-de-prova, que foram armazenados em água destilada 37ºC por 24 horas. Decorrido esse período, os corpos-de-prova foram unidos ao dispositivo de teste e ensaiados em uma máquina universal de ensaios (EMIC DL 500), com velocidade de 0,5 mm/min. A resistência a de união foi calculada em Mpa, e os dados foram analisados estatisticamente pelo teste "t" de Student. Os resultados (MPa±DP) indicaram que a aplicação do adesivo Clearfil SE Bond resultou em maior média de resistência de união (26,74±7,53a), com diferença estatística em relação ao adesivo Clearfil S3 Bond (20,94±5,48b). De acordo com a revisão de literatura, a união à dentina parece ser instável para os sistemas adesivos simplificados (aqueles que contêm os componentes hidrófilos e hidrófobos em um só frasco)

The objective of this study was to evaluate the microshear bond strength of two self-etching adhesive systems on bovine dentin, and discuss some concepts involving contemporary adhesives, and shear bond strength tests. Bovine incisors were prepared using silicon carbide papers to obtain flat surfaces of middle dentin (60mm2). The adhesives Clearfil SE Bond/Kuraray and Clearfil S3 Bond/Kuraray were applied, and Tygon tubing positioned over each sample of hybridized dentin. The interior space was filled in with RelyX ARC (3M Espe) resin cement. After photoactivation, the tubes were removed and samples were exposed, which were stored in distilled water at 37ºC for 24 hours. After this period, the samples were bonded to the test device, and tested in a universal testing machine (EMIC DL 500) with a speed of 0.5mm/min. The bond strength was calculated in MPa and the data were analyzed statistically by the Student "t" test. The results (MPa±DP) indicate that the application of the adhesive Clearfil SE Bond resulted in higher bond strength (26.74±7,53a), with a statistical difference in relation to the adhesive Clearfil S3 Bond (20.94±5,48b). According to the literature review, the dentin bond appears to be unstable for simplified adhesive systems (those which contain hydrophilic and hydrophobic components in the same bottle)

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OBJECTIVE: The aim of this study was to describe the interaction pattern formed between dentin and resin on cavities prepared with an erbium laser (Er:YAG). The morphological aspect of the irradiated dentin after acid etching was also observed. METHODS: Ten dentin disks were obtained from fresh extracted third molars. Each disk received two cavities, one prepared with a conventional high-speed drill, while the other cavity was obtained by the use of an Er:YAG laser (KaVo KEY Laser, KaVo Co.). The laser treatment was performed with 250 mJ/pulse, 4Hz, non contact mode, focused beam, and a fine water mist was used. Five disks were prepared for morphological analysis of the acid etched dentin. The other five disks had their cavities restored with Single Bond (3M) followed by Z100 resin (3M). The specimens were observed under scanning electron microscopy after dentin-resin interface demineralization and deproteinization. RESULTS AND CONCLUSIONS: It was observed that the morphological characteristics of the acid-etched irradiated dentin were not favorable to the diffusion of monomers through the collagen network. The dentin-resin interfacial aspect of irradiated dentin, after acid etching, showed thin tags and scarce hybridization zones, which agreed with the morphology of the irradiated and acid-etched dentin substrate observed.

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A técnica de esplintagem utilizada constitui um dos fatores que influenciam na cicatrizaçäo periodontal após a luxaçäo ou avulsäo dentária. Visto que há uma grande variedade de técnicas de contençäo, torna-se necessária uma avaliaçäo destas em relaçäo ao propósito a que se destinam. Atualmente acredita-se que os movimentos fisiológicos favorecem à cicatrizaçäo funcional do ligamento periodontal. E por esta razäo que se preconiza a utilizaçäo de um esplinte funcional já que, ao mesmo tempo em que promove a estabilizaçäo do dente, permite a açäo destes movimentos. Este trabalho tem por objetivo revisar os princípios de esplintagem de dentes traumatizados e apresentar uma análise de alguns tipos de ferulizaçäo

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