An 11-year clinical evaluation of leucite-reinforced glass-ceramic crowns: A retrospective study

Objective: The purpose of this study was to retrospectively evaluate leucite-reinforced glass-ceramic crowns placed over a 6-year period at two different private dental practices. Method and materials: One hundred twenty-five Empress crowns were placed in 54 patients. The 93 anterior and 32 posterior crowns were evaluated clinically with a mirror and probe, radiographically, and from clinical photographs, in accordance with a modified California Dental Association and Ryge quality evaluation system. The risk of fracture was determined with the Kaplan-Meier survival analysis. Results: Crowns were studied over periods ranging from 4 to 11 years. The probability of survival of the 125 crowns was 95.2% at 11 years (98.9% in the anterior segment and 84.4% in the posterior segment). Six crowns had to be replaced. Most of the 119 successful crowns were rated excellent; Alfa ratings were assigned to 94.2% for color match, 91.6% for porcelain surface, 86.6% for marginal discoloration, and 94.2% for marginal integrity. Conclusion: Leucite-reinforced glass-ceramic crowns showed a low clinical failure rate and excellent esthetics after up to 11 years.