Strength of posterior composite repairs using different composite/bonding agent combinations.

Posterior composites are becoming a viable alternative to amalgam in selected cases. As the use of posterior composites increases, the necessity of repair of fractured, discolored, or worn restorations will increase. A number of studies have demonstrated that clinically acceptable repairs can be obtained for anterior composites. This study examined the bond strength of repairs made to aged posterior composite substrates when different bonding agent/composite pairs were used. Dentin bonding agent/composite pairs gave the highest bond strengths and were greater than the bond strength of resin to etched enamel. An enamel bonding agent/composite repair gave the lowest bond strengths, which were less than resin/etched enamel bond strengths.