Related Experiment Video
Updated: Aug 25, 2026
Standardized Protocol to Evaluate the Effect of Surface Treatments, Luting Cements, and Thermocycling on PEEK–Composite Bond Strength
Published on: June 9, 2026
The resin-coating technique. Effect of a single-step bonding system on dentin bond strengths
Toru Nikaido1, Yasuko Nakaoki, Miwako Ogata
1Cariology and Operative Dentistry, Department of Restorative Sciences, Graduate School, Tokyo Medical and Dental University, Tokyo, Japan. nikaido.ope@tmd.ac.jp
Purpose:
An experimental single-step bonding system, RZ-II, has been developed as a resin coating material for crown preparation. The purpose of this study was to compare the dentin microtensile bond strengths (MTBSs) of RZ-II in direct and indirect use.
Materials And Methods:
Human molar dentin was used. The specimens were divided into three groups of n = 20 each. Group 1: RZ-II was applied to the dentin surface once or twice, and built up with a direct composite. Group 2: The dentin surface was provisionally covered and stored in water for 1 day. The provisional material was removed and an indirect composite was then bonded to the dentin surface. Group 3: RZ-II was applied to the dentin surface once or twice for "resin coating" before the placement and removal of provisional material. An indirect composite was then bonded to the coated dentin. After 1 day, MTBSs were measured at a crosshead speed of 1 mm/min. 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.
Results:
The MTBSs of RZ-II in Groups 1 and 3 were significantly higher than those of Group 2 (p < 0.05). The thickness of the resin-coating layer and the hybrid layer were 5 to 6 microm and less than 1 microm, respectively.
Conclusion:
The single-step bonding system, RZ-II, could be useful as a resin coating material for crown preparation.
