Effect of admixed indium on the clinical success of amalgam restorations

The purpose of this study was to clinically evaluate two formulations of a dispersed-phase, high-copper dental amalgam alloy (Indisperse), which contained admixed indium. One alloy tested contained 5% indium, and the second alloy contained 10% indium. A similar alloy without indium, Dispersalloy, was also placed for comparison. Over the course of the five-year study, there were no differences clinically or statistically regarding texture and luster. The margins of the restorations containing indium incurred slightly less fracture than the non-indium-containing restorations; however, these differences were not clinically significant. It can be concluded that the admixture of 5-10% indium as well as the increased ratio of eutectic spheres to lathe-cut particles found in the indium alloys enhance the clinical performance of amalgam restorations.