Comparative Evaluation of Shear Bond Strength between Porcelain and Commercially Available Cobalt Chromium Alloys – An In-Vitro Study

Life Science - Prosthodontics

Abstract

The aim of the study was to compare the shear bond strength of porcelain to three commercially available cobalt-chromium alloys. There were studies evaluating shear bond strength between porcelain and nickel chromium alloys and hence this study was conducted to evaluate shear bond between cobalt-chromium alloys. Our objective is to evaluate the pattern of bonding of porcelain to cobalt-chromium alloys and also to compare the shear bond strength of porcelain with cobalt-chromium alloys. A total of 30 samples, each 10 samples of Castco, Wironit, and Girobond NBS cobalt-chromium alloy were subjected to porcelain (Vita V60 i-Line) firing. After the porcelain firing, all the samples were then tested for the shear bond strength by using the Instron (Universal testing machine). After testing the samples, the data were tabulated and analysed using one way ANOVA test (p<0.05) using the SPSS software. The mean shear bond strength of Wironit alloy on porcelain when evaluated was 9.9 with standard deviation of 1.92. The mean shear bond strength of Castco alloy on porcelain was 11.9 with standard deviation of 3.5. The mean shear bond strength of Girobond NBS alloy on porcelain was 9.9 with standard deviation of 3.1. From the above results, it was concluded that the Castco alloy achieved significantly higher bond strength compared to the other two. Given the sample size, we conclude that Castco has superior bond strength over Wironit and Girobond NBS. In future, research relating to the tensile and compressive bond strength between porcelain and cobalt-chromium alloy can be considered.