Effect of the amount of light energy transmitted through CAD/CAM resin block on bonding performance of four types of resin cement adhesive systems

Resin-ceramic hybrid materials for computer-aided design/computer-aided manufacturing (CAD/CAM resins) have been developed. In this study, the effects of the amount of light energy transmitted through the four types of 1.5-mm-thick CAD/CAM resin blocks on the bond performance of corresponding resin cement adhesive systems consisting of an adhesive and a dual-curable resin cement were examined. The bond strengths of the four types of resin cement adhesive systems decreased with decreasing the amount of light energy transmitted through CAD/CAM resin block, due to a decrease in the light-curable ability of dual-curable resin cements. However, the degradation behavior of the bond strengths was strongly affected by the types of adhesives and initiator systems utilized. The adhesive consisting of a dimethacrylate monomer and redox-initiators enhanced the bonding performance of the dualcurable resin cement more effectively than the adhesive, which consists of a dimethacrylate monomer and photo-initiators or a gamma-me thacryloxypropyltrimethoxysilane and a 10-methacryloyloxydecyl dihydrogen phosphate.