EFFECT OF DIFFERENT POLYMERIZATION DEVICES ON THE SHEAR BOND STRENGTH BETWEEN DIFFERENT METALS AND AN INDIRECT RESIN

Abstract

Purpose: To evaluate the effect of different polymerization units on the shear bond strength between different metals and a laboratorial resin. Method: Sixty metallic cylinders were obtained (5mm x 4mm), thirty in commercially pure titanium (CpTi) and thirty in gold-palladium alloy (Au-Pd), which were sandblasted (Al2O3 110µm, 20s, 2,9 bar) before the resin application. Two layers of opaque (Sinfony Opaque) were applied with a brush and with the assistance of the teflon matrix, the esthetic veneering resin was applied on the metallic cylinders. The opaque and veneering resin were polymerized at different polymerized, according to experimental groups: GrA1 – CpTi + Visio Beta (3M ESPE/EUA); GrA2 – CpTi + Powerlux (EDG, Brazil); GrA3 – CpTi + Strobolux (EDG, Brasil); GrB1 – Au-Pd + Visio Beta; GrB2 – Au-Pd + Powerlux; GrB3 – Au-Pd + Strobolux. The specimens were submitted to shear test in a universal testing machine (model DL/1000-EMIC) with a 500kg load cell (0,5 mm/min). The data (MPa) were submitted to the analysis of variance (ANOVA) and tukey’s test (5%). Results: The means and standard deviations obtained were (MPa): GrA1: 6.1±1.9; GrA2: 5.6±1.4; GrA3: 5.5±2.5; GrB1: 9.4±2.5; GrB2: 7.4±2; GrB3: 8.2±3.1. Only the principal factor “metal” (p=0.0001<0.05) presents statistical significance (Au-Pd=8.39 MPa, Ticp= 5,7 MPa). The “polymerized units” (p=0,2062>0.05) did not influenced the bond strength between resin and metal (VisioBeta= 7,8 MPa; Powerlux=6,6 MPa; Strobolux=6,8 MPa). Conclusion: The Au-Pd alloys promote higher bond strength to sinfony indirect resin compared to Ticp, regardless the polymerized unit used. Descriptors: shear bond strength; commercially pure titanium; Au-Pd alloy; indirect resin; polymerized unit.