Hybrid Layer as a Dentin‐Bonding Mechanism

Journal of Esthetic and Restorative Dentistry (Impact Factor: 0.96). 07/2007; 3(4):133 - 138. DOI: 10.1111/j.1708-8240.1991.tb00985.x

ABSTRACT A number of mechanisms (both mechanical and chemical) have been proposed as the cause of dentin adhesion. Extensive research in Japan during the past 10 years has shown that strong, long-lived bonds between resin and living dentin will form when a monomer such as 4-META, which contains both hydrophilic and hydrophobic chemical groups, penetrates the tissue and polymerizes in situ. This resin-impregnation creates a transitional “hybrid” layer, that is neither resin nor tooth, but a hybrid of the two. The thin layer of resin-reinforced dentin locks the two dissimilar substances together on a molecular level, sealing the surface against leakage and imparting a high degree of acid resistance.