ADHESIVE INTERFACE BETWEEN RESIN AND ETCHED DENTIN OF CERVICAL EROSION ABRASION LESIONS

The interfacial structure between an adhesive composite resin and the dentinal walls of cervical erosion/abrasion lesions etched with 37% ph osphoric acid gel for 60 seconds was investigated. Almost all dentinal tubules were occluded with rodlike structural depositions that remain ed undissolved even after acid conditioning. The hybrid layer between the adhesive resin and surface-demineralized dentin was found to be 0. 3 to 3 mum, much thinner than that routinely found in either normal de ntin or cariously affected dentin. The hybrid layer was thinnest at th e occlusal walls of the cavity where the dentinal tubules run parallel to the cavity surface. The bond strength of adhesive resin to these a reas may differ from that to intact normal dentin.