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.