Correlation between air-drying duration and bond strength of composite resins to teeth

Cavity preparations involve both enamel and dentinal walls, but moisture contamination of these surfaces adversely influences the effectiveness of bonding interface. This in vitro study investigated the relationship between air-drying time and the bond strength to bovine enamel and dentin for two types of composite resins and their bonding agents. Comprehensive shear bond tests were performed with a universal testing machine, and mean bond strengths were computed by an analysis of variance and by Scheffé's multiple comparison test. No statistical differences were noted between the bond strength to the unetched and etched enamel and air-drying duration for bondings. The bond strengths to the etched dentin was comparable despite the time of air drying, but the bond strengths to unetched dentin were dependent upon the length of air drying.