In vitro evaluation of marginal leakage of corrosion-resistant amalgam alloy.

Restorations placed without coating the cavity walls with cavity varnish exhibited significant marginal leakage at all time intervals; however, there appears to be some reduction of leakage after six months. Restorations placed after coating the cavity walls with cavity varnish demonstrated no leakage at forty-eight hours and three months. Velvalloy and Dispersalloy restorations exhibited no leakage at six months, although there was a slight leakage at one year. Spheraloy restorations with cavity varnish demonstrated some leakage at six months and one year. The results of this study appear to correlate with previous studies using the same technique to determine marginal leakage. Apparently, the corrosion resistance of the dispersed phase alloy does not increase the marginal leakage, when compared with the conventional and spherical alloys.