The effects of surface treatment of dental nickel-chromium alloy on tensile bond strength

Lee, Eun Suk; Kwon, Oh Won

Abstract

This study was conducted to evaluate the tensile bond strength by bonding the dental bracket with Super-bond after treating the surface of dental Nickel-Chromium alloy with sandblasting, sandblasting & tin-plating, respectively, and tin-plating. 10 pieces of Nickel-Chromium alloys with brackets bonded with Super-bond without their surface treatment were sampled as a control group, 20 pieces of Nickel-Chromium alloy brackets bonded with Super-bond after treating them with sandblasting as group I, 20 pieces of Nickel-Chromium alloys tin-plated and bonded with Super-bond after sandblasting as group II, and then 20 pieces of alloys with brackets bonded with Super-bond after tin-plating as group III. The result of those examination and comparison is summarized as follows: 1. Group I showed the mean tensile bond strength of 14.41+/-2.24MPa which was highest among 4 groups, followed by group III( 13.59+/-L51MPa ), group II( 12.27+/-1.45MPa ), and control group( 10.50+/-1.57MPa ), respectively. However, it was shown that them was no statistically significant difference between group I and III, group III and II, and group II and control group( P>005 ). 2. The main failure pattern of those brackets showed that 70% of the control group had an adhesive failure at the bracket Superbond interface, and 30% at the Nickel-Chromium alloy-Superbond interface, while other groups did the adhesive failure at the bracket-Superbond interface. 3. When examined under SEM, it was shown that adhesives were mostly attached to the surface of the Nickel-Chromium alloy for all groups while a considerable quantity of adhesives were attached to the bracket base. Then, those samples treated only with sandblasting showed the most even and remarkable roughness of their surface.