Etched casting acid etch composite bonded posterior bridges.

Abstract

The development of composite bonded cast posterior bridges is followed through its evolution from the perforated to the electrolytically etched casting for resin retention. The current state of the art in design and preparation for these retainers is reviewed stressing the path of insertion, proximal extensions, occlusal rests and gingival extent. Retainer fabrication and the alloy specific nature of the electrolytic etching process are discussed. The sequence and concerns in the acid etching of lingual tooth structure and subsequent bonding order for etched casting is described. x\.cid etch composite bonded posterior bridges have only recently been employed clinically and have undergone a rapid evolution. These bridges utilize a cast framework which is composite bonded to the proximal and lingual enamel surfaces of the abutment teeth. The major areas of evolution are in the method of composite retention of the alloy framework (the resin to alloy interface) and in the criteria for abutment tooth enamel modification. These bridges represent an extremely conservative method of restoration as the abutment teeth undergo only modification to enamel contours, therefore making the technique reversible should the bridge be removed.