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 1, 20 pieces of Nickel-Chromium alloys tin-plated and bonded with Super-bond after sandblasting as group 11, and then 20 pieces of alloys with brackets bonded with Super-bond after tin-plating as group 11L
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 a group 111 an,´ II, and group- 11 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, "-bile 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.
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