Abstract
An experimental single-step bonding system, RZII (Sun Medical), has been developed as a resin coating material. The purpose of this study was to evaluate the dentin bonding of RZII using micro-tensile bond strength (MTBS) test and a SEM observation. RZII was applied to the human molar dentin once or twice for “resin coating”. After storage in water for 1 day, a cured composite was cemented to the coated dentin using a resin cement, Chemiace II (Sun Medical). For the control group, a cured composite was cemented to the dentin surface using Chemiace II without resin coating. After storage in water for 1 day, MTBSs were measured at a crosshead speed of 1mm/min. Number of the specimens for each group was twenty. The data were analyzed using one-way ANOVA and Fisher's PLSD test (p=0.05). The interface between the indirect composite and resin-coated dentin was also observed using a SEM. The MTBSs with RZII were approximately 25 MPa, which were significantly higher than that without resin coating (p<0.05). The thickness of the resin-coating layer and the hybrid layer were 5-6μm and less than 1μm, respectively. RZII could be useful as a resin coating material for crown preparation.
