Class 2 composite restorations: prevention in vitro of contraction gaps.

The present in vitro study has shown that it is possible to prevent marginal contraction gaps at composite restorations in the proximal section of Class 2 cavities by use of a condensable composite and adequate condensers. An explanation of condensation to eliminate the wall-to-wall polymerization contraction is suggested, and a possible complete Class 2 composite technique is outlined. The subject studied is only one of several problems that must be analyzed before acceptance of composite resins as Class 2 restoratives can be made possible.