Long-term clinical study of porcelain-fused-to-gold restorations

Abstract

S everal years ago porcelain-fused-to-gold (PFG) restorations were introduced to fixed partial denture prosthodontics. The new materials and related clinical techniques represent an important step toward an optimal solution to many problems in fixed prosthodontics, especially in the anterior region. The method combines the esthetic qualities of porcelain with the strength, accuracy, and marginal adaptation of the metal. Several studies have been published on the clinical and material aspects of PFG restorations.‘-6 The chemical characteristics of the porcelain-to-gold bonding and the possible defects caused by inadequate laboratory procedures also have been reported.‘-‘” Much attention has been paid to the strength of the bonding between gold and porcelain.“.?’ Hobo and Shillingburg2r described the specific preparation techniques and the coping design. In histologic studies others showed the positive clinical tolerance of the marginal periodontium to the porcelain.?“‘“’ As far as we know, only one long-term clinical study of PFG restorations has been published.3’ The purposes of this clinical long-term survey were to examine the frequency of mechanical failures of PFG restorations and to provide some suggestions for their possible prevention. -