Abstract: Objective: To investigate the effects of matrix metalloproteinase inhibitor baicalein and puerarin combination with ethanol wet bonding on the durability of dentin bonding. Methods: 128 isolated teeth were selected and randomly divided into 8 groups, 16 in each group. Group A was control group, group B was treated with ethanol, groups C, D and E were treated with 0.05%, 0.1% and 0.5% baicalein ethanol. Group F-H were treated with 0.05%, 0.1% and 0.5% puerarin ethanol, and 8 specimens were randomly selected for aging treatment in each group. Each group of specimens was subjected to shear strength test, fracture mode analysis, and scanning electron microscope observation of the mixed layer. Results: The immediate shear strengths of group C-H were higher than those of group A and B (P<0.05). The shear strengths of group C-H were not significantly reduced after aging (P>0.05), however, the shear strengths of group A and B were significantly reduced after aging (P<0.05). Scanning electron microscope observation found that the resin densification degree of mixed layer in the experimental group was higher than that in the control group. Conclusion: The wet bonding of baicalin and puerarin combined with ethanol can improve the immediate bonding strength of dentin and enhance the duration of dentine bonding.

Key words: dentin bonding, baicalein, puerarin, alcohol wet bonding