Effect of different surface treatments on bonding strength of composite resin to commercially pure titanium

To investigate the effectiveness of different surface treatments that could promote the bond strength of composite resin to commercially pure titanium. The 24 casting pure titanium specimen were randomly divided into four groups: Smooth group, rough group, acid etching smooth group, acid etching rough group. Each group had six specimens. In the different groups, the specimens were treated respectively under different surface treatments. The specimens of rough group was sandblasted, the acid etching smooth group was treated by acid etching, the acid etching rough group was treated by acid etching after sandblasting, the smooth group had no treatment. After surface treatment, the casting pure titanium specimens that were veneered by composite resin became titanium-composite resin specimen. Then the bond strengths were evaluated by universal testing machine and the surfaces were observed by scanning electron microscope including titanium surface appearance and titanium surface appearance of different groups afte