Influence of light-curing unit systems on shear bond strength and marginal microleakage of composite resin restorations

Abstract

The aim of the present study was to evaluate the influence of different photopolymerization (halogen, halogen soft-start and LED) systems on shear bond strength (SBS) and marginal microleakage of composite resin restorations. Forty Class V cavities (enamel and dentin margins) were prepared for microleakage assessment, and 160 enamel and dentin fragments were prepared for the SBS test, and divided into 4 groups. Kruskal-Wallis and Wilcoxon tests showed statistically significant difference in microleakage between the margins (p < 0.01) with incisal margins presenting the lowest values. Among the groups, it was observed that, only at the cervical margin, halogen soft-start photo polymerization presented statistically significant higher microleakage values. For SBS test, ANOVA showed no statistical difference (p > 0.05) neither between substrates nor among groups. It was concluded that Soft-Start technique with high intensity end-light influenced negatively the cervical marginal sealing, but the light-curing systems did not influence adhesion.

Chemical and morphological features of dental composite resin: Influence of light curing units and immersion media

“…There are several important factors that may influence the rate of polymer degradation: the type of chemical bond with the polymer chain, copolymer composition, water sorption, and the pH of the immersion media (Gopferich, 1996). One of the main influent factors is the intensity of light unit and its correct application that allow a great degree of polymerization (Sassi et al, 2008).…”

Implicações Clínicas Envolvidas no Processo de Fotopolimerização da Resina Composta

“…Sendo assim, o sucesso a longo prazo das restaurações de resina composta está diretamente relacionado à polimerização precisa, que é crucial para obter propriedades físico-químicas ideais 12 . Nesse âmbito, o grau de conversão do monômero em polímero é o fator que determina a qualidade da polimerização.…”

Ensaio de microinfiltração: revisão da literatura

“…Apesar da facilidade da técnica, é fundamental que os observadores sejam calibrados. Outro modo de leitura é a Análise Quantitativa (morfométrica) (Cenci et al 9 , 2005, Sassi et al 35 , 2008, Pereira 55 , 2007). Neste caso, os cortes dentais são escaneados e as imagens obtidas são transferidas para um software que mede a extensão ou a área da penetração do corante ou traçador (Cenci et al 9 , 2005)…”