Prospective study on metal ceramic crowns in private practice settings: 20-year results.

Objectives: Posterior metal ceramic crowns are still widely used as a standard treatment. The aim of this study was to obtain long-term data on their clinical performance.Material and Methods: Ten private practitioners participated in this prospective practice-based study. Patients were provided with two crowns each. Two groups were formed. The single crown group comprised 95 patients with 190 crowns. The retainer crown group comprised 138 patients with fixed dental prostheses and 276 retainer crowns.Results: For the primary outcome "loss of tooth or crown," 20-year survival rates of 78.8% in the single crown group and 67.8% in the retainer crown group were found. Veneering ceramic defects occurred rather frequently, resulting in respective 20-year technical success rates of 74.2% for single crowns and 62.9% for retainer crowns. However, veneering ceramic defects causing crown losses were very rare events.Conclusions: The results contribute to our knowledge on long-term outcomes of treatments with metal ceramic crowns and show high survival and success rates over 20 years.Clinical relevance: Posterior metal ceramic crowns are a highly reliable option in private practice settings. [ABSTRACT FROM AUTHOR]