Comparison of Bond Strength of Porcelain to Metal in Nobel, Base Metals (with and without) Beryllium with SEM/EDS Analysis

Evaluation of bonding in atomic level, by SEM/EDS analysis of Si atoms, is an exact method for determination of bond strength of metal and porcelain. The purpose of this study was to evaluate the bond strength of one noble alloy and two base metal alloys with and without beryllium.Methods and materials: Six specimens of each alloy Begostar, Rexillium III, Wiron 99 (10×10×1mm dimensions) were prepared. All specimens were airabraded with 50 μm aluminium oxide particles. Vita VMK 95 porcelain was fused on the central 6 mm diameter circular area of each specimen with 1 mm thickness. Porcelain was debonded by planar-shear test at a cross- head speed of 0/5 mm/min. Specimens were analyzed by SEM/EDS (Scanning Electron Microscope/Energy Dispresssive Spectroscopy) analysis 3 times throughout the study to determine the Si atomic percentage. Bond strength of porcelain to alloys was characterized by determining the Area Fraction of Adherent Porcelain (AFAP). Results were analyzed by one-way analysis of variance and LSD test. Statistical analysis showed a significant difference in the AFAP values among groups. AFAP value of noble alloy group (0.97±0.07) was significantly higher than other groups. For base metal groups, AFAP value of beryllium group (0.45±0.13) was significantly higher than non-beryllium group (0.17±0.04). Superior AFAP values of noble alloys, confirm better bond strength between noble alloys and porcelain as compared with base metal alloys. Also, in base metal alloys, specimens with beryllium, have a higher AFAP values and higher bond strengths.