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ResumoA adequada fotopolimerização das resinas compostas é fundamental para obtenção de uma boa dureza capaz de resistir aos esforços mastigatórios. Assim, o objetivo deste estudo foi avaliar a influência das técnicas de fotopolimerização -Convencional (CONV), Soft-start (SS) e Pulso atrasado (PA) na microdureza Knoop de três resinas compostas. Para a confecção dos corpos-de-prova foram utilizadas as resinas compostas Filtek Z350 (3M ESPE), Empress Direct (IvoclarVivadent) e P90 (3M ESPE). Foram obtidos nove grupos experimentais em função da técnica de polimerização e resina composta. Vinte e quatro horas após a fotopolimerização foi realizado o teste de microdureza Knoop nas superfícies de base e topo de cada corpo-de-prova. Assim, os valores obtidos foram submetidos ao teste de Kruskall Wallis, seguido do teste de Dunn, p < 0,05. A eficácia da polimerização na superfície de topo das resinas compostas testadas não foi afetada pelos diferentes modos de polimerização. A resina composta Empress Direct apresentou os mais baixos valores de dureza para todos os modos de polimerização quando comparada às demais resinas compostas avaliadas. Palavras-chave: fotopolimerização, dureza knoop, resina composta. AbstractProper curing of composites is critical to obtaining good toughness able to withstand masticatory forces. The objective of this study was to evaluate the influence of curing techniques -conventional (CONV), Soft -start (SS) and Pulse delayed (PA) in microhardness of three composites. To make up the body-of -evidence were used composites Filtek Z350 (3M ESPE), Empress Direct (IvoclarVivadent) and P90 (3M ESPE). Nine experimental groups were obtained according to the polymerization technique and composite resin. Twenty -four hours after curing was performed Knoop microhardness test surfaces of base and top of each body -of -evidence. Thus, the values obtained were subjected to the Kruskal Wallis test followed by Dunn's test, p < 0.05. The effectiveness of the polymerization on the top surface of the composites tested was not affected by different modes of polymerization. The Empress Direct composite resin showed the lowest hardness values for all modes of polymerization compared to other composites evaluated.

Objectives Conduct a histological comparison of the pulp response to different materials, with a focus on the continuity and morphology of the mineralized barrier after direct pulp capping. Materials and Methods One hundred and eight maxillary first molars of 54 Wistar rats were subject to direct pulp capping and divided into three groups according to the materials used: calcium hydroxide (CH), mineral trioxide aggregate (MTA), and Biodentine. All cavities were sealed, and the animals were euthanized at 7, 14, and 21 days. Descriptive histological evaluation of the inflammation and formation of the mineralized barrier was performed. Statistical Analysis Statistical analyses were performed using the Kruskal–Wallis test, which was complemented by the Dunn test; differences with p < 0.05 were considered statistically significant. Results The results showed that MTA and Biodentine elicited less intense inflammatory reactions than CH. With respect to the formation and quality of the dentin barrier formed, differences were observed at 21 days between the analyzed groups; the best results being obtained following treatment with MTA and Biodentine. Conclusion MTA and Biodentine induced formation of a more continuous and uniform mineralized barrier with less intense pulp response than CH.

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