Requirement for development of dental adhesives

Alan Boyde and his colleagues first described smear layers-covered dental hard tissues. Later, David Eick and his group examined smear layer-covered dentin and showed how acid-labile are smear layers. A superior bond strength has come to be provided for the resin-dentin interface in the current dental adhesive systems as a result that the acid-etching treatment for the enamel/dentin was examined to remove smear layers. Moreover, latest adhesive systems which gave top priority to convenience in clinic have developed. On the other hand, as a cause of the collapse of the resin-dentin interface, collagen degradation by host-derived enzymes (MMPs) has been focused attention. However, latest adhesive systems are not developed in consideration of improvement of the resin-dentin bond’s durability. Development of the dental adhesive that improves durability by inactivating dentin MMPs is required.