effect of zinc oxide nanoparticles with matrix metalloproteinase inhibitors on the shear bond strength of a universal dentin bonding agent to caries affected dentin

Objective: this study evaluated the effect of zinc oxide (zno) nanoparticles combined with matrix metalloproteinase (mmp) inhibitors on the shear bond strength (sbs) of a universal bonding agent to caries-affected dentin (cad).methods: forty extracted molar teeth were ground to expose dentin. cad was induced by immersing specimens in 10% citric acid for 4 hours. samples were divided into five groups (n=8) based on the surface treatment following acid etching: group 1: cad treated with hesperidin, group 2: cad treated with zno nanoparticles and hesperidin, group 3: cad treated with grape seed extract, group 4: cad treated with zno nanoparticles and grape seed extract, and group v: control (no surface treatment). g-premio bond was applied and then composite resin cylinders were bonded to the dentin surface. after thermocycling, the bond strength of the specimens was measured using a universal testing machine. the data were analyzed by anova and tukey’s post hoc test, at a significance level of p < 0.05.results: a significant difference in sbs was observed between the study groups (p < 0.001). group 2 demonstrated the highest sbs (9.73 ± 0.37 mpa), followed by group 4 (8.76 ± 0.11 mpa), group 1 (7.68 ± 0.27 mpa), and group 3 (6.47 ± 0.34 mpa). the lowest bond strength was observed in the control group (4.32 ± 0.46 mpa).  all pairwise intergroup comparisons were statistically significant (p < 0. 05).conclusions: surface treatment with zno nanoparticles and mmp inhibitors enhances the bond strength of universal bonding agents to caries-affected dentin.