RESUMO
Objective: To evaluate the effect of a synthetic inhibitor of MMPs (Galardin) and its solvents [ethanol and dimethyl sulfoxide (DMSO)] on the microtensile bond strength (µTBS) of adhesive systems to dentin. Material and Methods: Sound human third molars (n=180) were randomly assigned into 5 based on solution type: DMSO; ethanol; Galardin + DMSO; Galardin + ethanol; and distilled water as control. Then were further subdivided into 6 based on the adhesive system, i.e. 3-step and 2-step etch-and-rinse (ER), one-step and 2-step self-etch (SE) and universal in ER and SE strategies. The samples underwent a 500-round thermocycling procedure at 5±5/55±5°C and were sectioned into 1-mm2 pieces perpendicularly in a cutting machine. The µTBS was measured at a strain rate of 1 mm/min. Data were analyzed with two-way ANOVA and post hoc Games-Howell tests (p<0.05). Results: The adhesive system and the solution had significant effects on the µTBS (p<0.001). The universal adhesive in the SE mode resulted in a significant decrease in µTBS compared to the other adhesives (p<0.05). Ethanol, too, resulted in a significant decrease in µTBS compared to other solutions (p<0.05). Conclusion: Galardin and its solvents, except for ethanol, had no detrimental effects on the immediate µTBS.
