Scanning electron microscope study of the junction between restorations and gingival cavosurface margins

This study demonstrates a definite interfacial void between the cervical margins of the tooth preparation and gold inlay, composite resin, and amalgam restorations. In addition, these marginal defects permit plaque formation within them. Furthermore, microleakage may be a complicating factor in this lack of fit. Restorations which may be "clinically acceptable" may not, in fact, be ideal because of the properties of the restorative materials. It would seem desirable, therefore, to encourage the development of new restorative materials that will bond to the tooth surface.