Experimental etch-and-rinse adhesive systems containing MMP-inhibitors: Physicochemical characterization and resin-dentin bonding stability

Objectives: To evaluate the degree of conversion (DC%), water sorption (WS), solubility (SO) and the resin-dentin bonding stability (mTBS) of experimental (EXP) etch-and-rinse adhesive systems containing MMP-inhibitors: Galardin-GAL, Batimastat-BAT, GM1489-GM1 and chlorhexidine diacetate-CHX. Methods: DC% was measured using FT-IR spectroscopy, while WS and SO were calculated based on ISO4049. Thirty-six human molars were wet ground until the occlusal dentin was exposed. The adhesive systems were applied and resin composite buildups were incrementally constructed. After 24 h immersion in distilled water at 37 degrees C, the specimens were cut into resin-dentin beams with a cross-sectional area of 1 mm(2). The mTBS was evaluated after 24 h, 6 months and 12 months of water storage at 37 degrees C. Adper Single Bond 2 (SB2) was used as a commercial control. The data were analyzed using ANOVA and Tukey's HSD test. Results: SB2 presented the highest DC% (p < 0.05). CHX presented the lowest WS (p < 0.05). GM1, GAL and BAT presented similar WS when compared with SB2 (p > 0.05). SO was found to be not significant (p > 0.05). All adhesive systems maintained mTBS stability after 6 months of water storage. Only BAT, GM1 and CHX maintained mTBs stability after 12 months of water storage. Conclusions: The experimental adhesive systems with GM1489 and chlorhexidine diacetate presented the best physicochemical properties and preserved resin-dentin bonding stability after 12 months of water storage. Clinical significance: GM1489 could be suitable for inclusion as an MMP-inhibitor in etch-and-rinse adhesive systems to maintain resin-dentin bonding stability over time. (C) 2015 Published by Elsevier Ltd.