The longevity of a composite resin restoration is constantly being sought in the field of dentistry. The matrix metalloproteinases (MMPs) and cysteine cathepsins (CCs) in the dentin matrix when activated participate in the degradation of collagen fibrils and extracellular components. The preservation of the structural integrity of collagen and the matrix maintains the mechanical properties, chemical stability and resistance to degradation of resin-dentin bonded interface, contributing to restoration durability. Thus, it is of fundamental importance to employ methods and / or agents that promote the inactivation of MMPs and CCs to improve the chemical stability of the adhesive interface. So, several crosslinking agents have been studied (natural and synthetic), however it is observed that chitosan and proanthocyanidin show reliable results and both promote protease inactivation and provide better collagen web resistance, and thus increase the longevity of the restoration procedure.
Key words: Adhesive systems, dentin, hybrid layer, metalloproteinases, cysteine cathepsins, crosslinking agents, protease inactivation