Abstract
OBJECTIVE: This study aimed to evaluate the effects of resin coatings on bond strength using immediate and delayed cementation protocols. MATERIALS AND METHODS: One hundred twenty dentin specimens were assigned to four groups: Noncoated, TK- 100B (a novel single-bottle adhesive), Hybrid Coat II, and Clearfil SE bond 2. The specimens of the latter three groups were resin coated with their respective materials. Each group was subdivided into immediate and delayed cementation after 1-week provisionalization with a polycarboxylate cement. All specimens were luted with resin cement and subjected to shear bond testing. Data were analyzed by two-way analysis of variance and Tukey's post hoc test (α = 0.05). RESULTS: TK- 100B and Clearfil SE Bond 2 produced significantly higher bond strengths than the non-coated group for both cementation schedules. Delayed cementation reduced the bond strengths of Hybrid Coat II and Clearfil SE Bond 2 (p < 0.05), whereas the non-coated group and TK- 100B showed no time-related changes. Most failures in the resin-coated groups occurred at the resin-cement interface. CONCLUSIONS: Bonding strength was enhanced with TK- 100B and Clearfil SE Bond 2. A 1-week delay weakened Hybrid Coat II and Clearfil SE Bond 2 but had no effect on non-coated dentin or TK- 100B, confirming material-specific effects. CLINICAL SIGNIFICANCE: Both the novel single-bottle adhesive TK-100B and the established Clearfil SE Bond 2 yield high bond strengths when used as resin coatings in both immediate and 1-week delayed cementation.