Effects of Chemical Cross-linkers on Caries-affected Dentin Bonding

The achievement of a strong and stable bond between composite resin and dentin remains a challenge in restorative dentistry. Over the past two decades, dental materials have been substantially improved, with better handling and bonding characteristics. However, little attention has been paid to the contribution of collagen structure/stability to bond strength. We hypothesized that the induction of cross-linking in dentin collagen improves dentin collagen stability and bond strength. This study investigated the effects of glutaraldehyde- and grape seed extract-induced cross-linking on the dentin bond strengths of sound and caries-affected dentin, and on the stability of dentin collagen. Our results demonstrated that the application of chemical cross-linking agents to etched dentin prior to bonding procedures significantly enhanced the dentin bond strengths of caries-affected and sound dentin. Glutaraldehyde and grape seed extract significantly increased dentin collagen stability in sound and caries-affected dentin, likely via distinct mechanisms.