Marina Di Francescantonio

Bond strength of resin cements to Co-Cr and Ni-Cr metal alloys using adhesive primers.

PURPOSE The aim of this study was to evaluate the effectiveness of adhesive primers (APs) applied to Co-Cr and Ni-Cr metal alloys on the bond strength of resin cements to alloys. MATERIALS AND METHODS Eight cementing systems were evaluated, consisting of four resin cements (Bistite II DC, LinkMax, Panavia F 2.0, RelyX Unicem) with or without their respective APs (Metaltite, Metal Primer II, Alloy Primer, Ceramic Primer). The two types of dental alloys (Co-Cr, Ni-Cr) were cast in plate specimens (10 x 5 x 1 mm(3)) from resin patterns. After casting, the plates were sandblasted with aluminum oxide (100 microm) and randomly divided into eight groups (n = 6). Each surface to be bonded was treated with one of eight cementing systems. Three resin cement cylinders (0.5 mm high, 0.75 mm diameter) were built on each bonded metal alloy surface, using a Tygon tubing mold. After water storage for 24 hours, specimens were subjected to micro-shear testing. Data were statistically analyzed by two-way ANOVA and Tukeys studentized range test. RESULTS The application of Metal Primer II resulted in a significantly higher bond strength for LinkMax resin cement when applied in both metal alloys. In general, the cementing systems had higher bond strengths in Co-Cr alloy than in Ni-Cr. CONCLUSIONS The use of AP between alloy metal surfaces and resin cements did not increase the bond strength for most cementing systems evaluated.

Adhesive bonding of resin cements to cast titanium with adhesive primers

The purpose of this study was to evaluate the effects of adhesive primer applications on the bond strength of resin cements to cast titanium. Four adhesive primers - Metaltite, Metal Primer II, Alloy Primer and Ceramic Primer - and their respective resin cements - Bistite II DC, Link Max, Panavia F 2.0, RelyX Unicem and RelyX ARC - were tested. Cast plates were prepared from titanium ingots (n=6 specimens/cement) and had their surfaces airborne-particle abraded with Al2O3 (50 μ m). Three resin cement cylinders were built on each bonded titanium surface, using a cylindrical translucent tubing mold and were subjected to micro-shear testing. Data were analyzed statistically by two-way ANOVA and Tukeys post-hoc test (α=0.05). The application of Metal Primer II and Ceramic Primer resulted in significant higher bond strength for Link Max and RelyX Unicem resin cements, respectively, than nonuse of adhesive primers. Panavia F 2.0 and RelyX ARC yielded high bond strength means with or without adhesive primers. The use of adhesive primers might increase the bond strength to cast titanium depending on the resin cement used.