The effect of calcium phosphate-containing desensitizing agent on the microtensile bond strength of multimode adhesive agent

Abstract

Objective: The aim of this study was to investigate the effect of calcium phosphate containing desensitizing pretreatments on the microtensile bond strength (MTBS) and microleakage of the multimode adhesive agent to dentin.

Materials and Methods: In this study, twelve noncarious, freshly extracted human third molar teeth for MTBS and 20 premolar teeth for the microleakage test were used. The teeth were restored using Clearfil Universal Bond + Clearfil APX and Teeth mate Desensitizer (TMD). For MTBS test, Group 1: Self‑etch, Group 2: Etch and rinse (G1 and 2, nondesensitizer treatment served as a control), Group 3: TMD/self‑etch, Group 4: Acid‑etch/TMD/etch and rinse. For microleakage test, Class V adhesive cavities (3 mm × 2 mm × 2 mm) were prepared and restored as mentioned before. The restored teeth were subjected to thermal cycling. The MTBS test was performed in all procedures. The MTBS data were submitted to a one‑way ANOVA and post hoc Tukey test (P < 0.05). One tooth in each group was prepared for scanning electron micrograph examination. Marginal microleakage was measured based on the penetration of a 0.5% basic fuchsin dye. Dye penetration was then scored. The data were submitted to the Kruskal–Wallis and Wilcoxon signed ranks tests (P < 0.05).

Results: Control groups exhibited a higher mean MTBS value than TMD groups, and there were statistical differences between the groups. TMD groups also demonstrated significantly less microleakage than control groups (P < 0.05).

Conclusions: This study proves that the application of TMD with a multimode adhesive bonding system produced significantly lower MTBS and microleakage.

Keywords: Calcium phosphate, desensitizer, microtensile bond strength, multimode dentin bonding agent