Attrition at the enamel-restoration interface.

At present, aesthetic restorative dental materials such as composite resin, porcelain, castable ceramics, etc are routinely used to restore the occlusal surfaces of posterior teeth. However, it is desirable that restorative materials should possess wear rate comparable to that of enamel. The purpose of this study was to evaluate the effects of hypothesized attrition at the enamel-restoration interface using various types of direct and indirect composite resins. Results showed that there was no correlation between the quantitative wear of the upper and lower specimens. Remarkable marginal integrity was observed in the majority of the specimens with no significant step formation at the margin thereby suggesting satisfactory transition. SEM evaluation of the worn surfaces revealed various morphological features.