RESUMO
AIM: This study assesses the effect of matrix metalloproteinases on microtensile bond strength (µTBS) of an etch-and-rinse adhesive system. METHODS: This in vitro study evaluated 88 extracted premolars. The teeth were sectioned to expose dentin and were then randomly divided into four groups (n = 22). In group 1 (control), dentin surface was etched, and Adper Single Bond 2 was applied. In groups 2-4, dentin surface was etched and chlorhexidine (CHX), 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC), and dimethyl sulfoxide (DMSO) were applied on the surfaces, respectively, and blotted dry. Next, Adper Single Bond 2 was applied and all teeth were built up with Z350 composite. In each group, half the samples immediately and the other half after 10,000 thermal cycles underwent µTBS test. Data were analyzed using ANOVA and Tukey's test (α = .05). RESULTS: In thermocycled samples, maximum µTBS was noted in CHX group followed by DMSO, EDC, and control group (p < .001). The thermocycled µTBS of composite to dentin was significantly higher in CHX group compared with EDC, DMSO, and control groups (p < .001) but was not significantly different in EDC and DMSO groups (p = .498). CONCLUSION: The thermocycled µTBS obtained by the application of CHX, EDC, and DMSO was significantly higher compared with the value to the control group.
