Effect Of Different Surface Treatments On Shear Bond Strength Between Co-Cr Alloy And Resin

Objective:To evaluate the effect of different surface treatments on shear bond strength between Co-Cr alloy and resin, and observe failure mode of all tested samples.Methods:Sixty casted metal sheets (13.0mm×9.0mm×3.0mm) were grinded to 400 grit with silicon carbide sandpaper in a polishing machine. After blasting, ultrasonic cleaning and drying, samples were randomly divided into two main groups for bonding Panavia F (A)and Ceramage(B) separately. According to the methods of surface treatment, every main group were randomly divided into there equal groups of 10 each:①no treatment(a);②metal primer(b);③hydrofluoric acid+metal primer(c). After storage in 37℃water for 24 hours, all samples were mounted in a custom-made jig and subjected to a shear bond strength test in a fatigue testing machine at a cross-head rate of 0.5 mm/min. The data obtained were submitted to the one-way ANOVA and SNK test, observed the failure mode of each tested sample.Results:Shear bond strength values (MPa) from the highest to the lowest were as follows:Bc group (23.20±5.54); Ac group (17.55±4.03); Bb group (16.70±5.11); Ab group (15.49±2.33); Ba group (14.88±3.10); Aa group (13.52±2.96). Bc group was significantly higher than other groups (P <0.05); significant difference (P<0.05) was not showed between every two groups except for Ac and Aa groups. Failure modes of samples were adhesive damage in Aa and Ba groups, and mixed damage in the other groups.Conclusion:The sheer bond strength between Co-Cr alloy and Ceramage is better than that of Panavia F resin cement; hydrofluoric acid and metal primer improved the bonding strength between Co-Cr alloy and resin.