A Randomized Controlled Clinical Trial of Feldspathic Versus Glass-Infiltrated Alumina All-Ceramic Crowns: A 3-Year Follow-up

Purpose: The aim of this randomized controlled clinical trial was to compare the outcome of feldspathic porcelain (group 1) and glass-infiltrated alumina all-ceramic (group 2) crowns. Materials and Methods: Patients were recruited based on inclusion/exclusion criteria, and 33 eligible subjects were assigned randomly to one of the two treatment groups. One hundred one crowns were placed predominantly in the anterior portion of the mouth and were cemented using resin cement. A baseline California Dental Association quality evaluation was completed, and Plaque and Gingival Index scores were recorded. Prosthetic and soft tissue scores were recorded for up to 3 years. Results: Five restorations experienced mechanical failure. Kaplan-Meier analysis showed that the 3-year survival probabilities for group 1 (0.94) and group 2 (0.95) restorations were comparable (P = .484). Plaque and Gingival Index scores for both groups were similar at the 3-year recall (P > .999). Marginal integrity, anatomical form, and color and surface scores were also similar for both groups (P > .05). Conclusion: Feldspathic and glass-infiltrated alumina all-ceramic crowns placed predominantly in the anterior portion have comparable biologic and prosthetic outcomes, as well as survival probabilities.