Role of Additional Retention on Marginal Adaptation and Sealing of Large Resin Composite Class II Restorations

Abstract

All groups with additional retention (G2 = 0.565, G3 = 0.346 and G4 = 0.078) showed fewer gap formations than the control group (G1 = 2.076). Similar results were found for microleakage tests. All groups presented an increase in gap extension after loading, with the exception of the group with gingival retention grooves (G4). G4 showed the best results in relation to both parameters. There was a low correlation between gap extension and microleakage.