Mussel Wet Adhesion Inspired Using Dopamine Methacrylamide As A Primer To Improve Dentin Adhesion

Objectves:The aim of this study is to evaluate whether a catechol-functionalized primer(Dopamine methacrylamide,DMA)can increase the microtensile bond strength(?TBS)of dentin adhesion and improve bonding interface in vitro.Methods:DMA was synthesized and characterized.A total of 50 flat dentin slabs of 50 human 3rd molars were prepared and allocated into two groups for DMA application(the DMA/experimental group)and distilled water(the DW/control group).The dentin slabs were etched by phosphoric acid,and treated with either DMA primer or distilled water before bonding using an etch&rinse adhesive system as standard clinic protocol(n=20 in each group).?TBS test was performed before and after thermocycling(×2,500 cycles at 5? and 55?).The morphology and quality of dentin/adhesive interfaces or the fractured interfaces were examined by scanning electron microscopy(SEM).Results:Mean ?TBS(MPa)values of the DMA group vs.the DW group were 27.10±11.34 vs.21.30±6.06(p<0.05)before thermocycling and 25.75±8.74 vs.19.87±6.59(p<0.05)after thermocycling.SEM observation of dentin-resin binding interface showed that the DMA group had lesser defects than the DW group.Conclusion:Our study revealed that catechol-functionalized DMA may increase the bonding strength and improve the integrity of the interface of dentin adhesive when used as a dental primer.