Efficacy of dentin bonding agents combined with self-etching dentin primers containing Phenyl-P

The bonding efficacies of three commercial dentin bonding agents and an intermediate resin combined with two self-etching dentin primers (aqueous solutions of methacryloxyethyl hydrogen phenyl phosphate (Phenyl -P, 20 wt%) and either hydroxyethyl methacrylate (HEMA, 35 wt%) or glyceryl methacrylate (GM, 35 wt%)) were examined by measuring the wall-to-wall contraction gap of a light-activated resin composite in a cylindrical dentin cavity prepared in extracted human teeth. Among the tested bonding agents, only one material showed complete adaptation between the resin composite and the dentin cavity margin i. e. a dual -cured agent that contained 10-methacryloxydecyl dihydrogen phosphate (MDP). The contraction gap of the intermediate resin was significantly reduced by pretreatment with the experimental self-etching dentin primers containing Phenyl-P.