Effect of the concentrations of calcium chloride and synthetic peptides in primers on dentin bond strength of an experimental adhesive system

The purpose of this study was to evaluate the microtensile bond strength (MTBS) of an experimental adhesive system, which was prepared using different concentrations of calcium chloride (CaCl2) and synthetic peptides (pA/pB). Specimens were divided into six experimental groups and two control groups. In the experimental groups, self-etching primers used in the adhesive system comprised both Primer-I (Clearfil SE Bond Primer (SEP) containing 1, 5, or 10 wt% CaCl2) and Primer-II (SEP containing 0.1, 1, 5, or 10 wt% pA/pB). The negative control group used Primer-I containing 10 wt% CaCl2 and Primer-II containing 10 wt% pA/pB. The positive control group used Clearfil SE Bond only. Respective primers, bonding resin, and composite paste were applied and photopolymerized individually on flattened dentin surfaces of extracted human molars. All specimens were subjected to MTBS testing (n=20). Two-way ANOVA revealed significant differences in MTBS among CaCl2 concentrations in Primer-I and pA/pB concentrations in Primer-II (p