Objective To study the influence of three different metal alloy surfaces treated with primer methacryloxy propyl trimethoxyl silane（γ-MPS） coupling agent on the bond strength of Filtek Z350 resin. Methods Total 36 specimens of nickel-chromium（Ni-Cr） alloy, pure titanium（Ti） and aurum-palladium（Au-Pd） alloy, each of 12 pieces produced by lost wax casting method, were divided into 6 groups. After treated with γ-MPS on the bonding surface, experimental group samples were adhered to Filtek Z350 resin, then compared with the surface without γ-MPS treatment. The tensile and shear strength of each group tested and the fracture sections were observed with scanning electron microscope（SEM）. Results Comparing the Ni-Cr alloy and pure Ti experimental group with them in control
group, the shearing strength of the experimental group was higher, and the differences were significant（P0.05）. Comparing the experimental groups, the shearing strength of pure Ti was higher than Ni-Cr alloy, both were higher than Au-Pd alloy（PTi experimental group showed more resin juts in the fracture surface, while the Au-Pd alloy in experimental group showed less resin juts. Conclusion γ-MPS can enhance the adhesion between metal and resin, but it is also related to the metal composition. γ-MPS can significantly increase the bond strength of resin and Ti or Ni-Cr alloy, but not the case of Au-Pd alloy and resin.
