Metal-ceramic failure in noble metal crowns: 7-year results of a prospective clinical trial in private practices.

PURPOSE The aim of this study was to evaluate the clinical performance of metal-ceramic crowns placed in 10 private practices. MATERIALS AND METHODS In this prospective clinical trial, 95 patients were provided with 190 noble-metal metal-ceramic single crowns. RESULTS The 7-year survival rates of the crowns were 95.5% (target event: any removal), 99.5% (target event: removal because of defective veneer), and 92.4% (target event: metal-ceramic complication of any kind). No significant explanatory variables for metal-ceramic complications could be detected by bivariate and multivariate testing. The consequences resulting from metal-ceramic defects were of minor clinical significance in most cases. CONCLUSION The findings support previous claims that metal-ceramic restorations perform very well clinically, including in practices outside academic environments.