Influência da Distância de Fotoativação na Microdureza de um Compósito de Baixa Contração de Polimerização
Resumo
O objetivo deste estudo foi avaliar a influência da distância de fotoativação na microdureza de uma resina composta de baixa contração de polimerização. Amostras (5 mm x 2 mm) foram confeccionados com um compósito a base de silorano e polimerizados com as distâncias de 0, 2 e 4 mm entre a ponta do fotopolimerizador e a superfície do material. A microdureza das superfícies de topo e base foi avaliada usando um microdurômetro, com carga de 50 g durante 15 s utilizando um indentador Knoop. Os dados foram estatisticamente analisados pelos testes de ANOVA e Tukey (α = 0,05). Quando as amostras foram fotopolimerizada à 4 mm de distância a microdureza foi reduzida em comparação as distâncias de 0 e 2 mm (p < 0.001), que não apresentaram diferença estatística entre si (p > 0,05), e a superfície de topo apresentou maior microdureza do que a base (p < 0,001). Durante a restauração de cavidades profundas o uso de aparelhos de fotoativação com maior irradiância é recomendado para se obter melhores propriedades físicas.Descritores: Resinas Compostas; Dureza; Polimerização.
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