Evaluation of two methods for assessing marginal leakage.

This in vitro study demonstrated a significant difference in the microleakage of Class V preparations which had been etched, treated with a bonding agent, and restored with composite resin. This difference is dependent upon whether the specimen was thermocycled or immersed in a constant temperature dye bath. Therefore, it would seem reasonable that, to more accurately correlate laboratory findings with clinical performance, in vitro experimentation should simulate oral conditions as closely as possible. For testing microleakage, thermocycling as described in this study is superior to static temperature studies.