Marginal leakage: entry side and exit side-clinical implications.

The marginal leakage along the proximal walls of Class II amalgam restorations was studied. The influence of the direction of the bur rotation to tooth structure in cavity preparation was the primary concern of investigation. Also, the effect of different cavity wall finishing techniques created by exit and entry action of the rotating bur and that of two different types of amalgam on the marginal leakage was studied. The degree of marginal leakage was not significantly different among any of the treatment groups.