Dentin cavity pretreatments to improve the bond strength of direct and CAD/CAM restorations using resin composite.

Dentin cavity wall pretreatments to improve the bond strength of direct and computer-aided design/computer-aided manufacturing (CAD/CAM) restorations using resin composite were examined. Experiment 1 divided 18 standardized MOD cavities into three conditions: no pretreatment (Group N, control); chemical pretreatment with EDTA solution (Group C); and mechanical pretreatment with glycine air-powder polishing (Group M). Specimens were restored using direct resin composites. Micro-tensile bond strength (μ-TBS) was measured after cyclic loading. The μ-TBS was significantly higher for Groups C and M than for Group N. Group M showed the best bonding reliability. In Experiment 2, cavity preparation, dentin pretreatment, cyclic loading, and μ-TBS testing were performed using the same methods applied in Experiment 1. Specimens were restored using CAD/CAM resin composite inlays. The μ-TBS was significantly higher for Groups C and M than for Group N. No significant difference in bonding reliability was apparent among all groups.