Clinical Performance of All-ceramic Posterior Crowns. A Randomized, Prospective Clinical.

90 monolithic tooth-supported crowns are planned to be included in the study; 30 crowns of high translucent zirconia (BruxZir, Glidewell), 30 crowns of high translucent zirconia (BruxZir, Glidewell) with a mini-veneer of porcelain and 30 crowns of lithium-disilicate glass-ceramic (IPS e.max CAD, Ivoclar Vivadent AG, Schaan, Liechtenstein). Patients with indications for single crowns will be recruited from three general dental clinics. Inclusion criteria for participating in this study are patients in need of crowns in the posterior dentition, premolars and molars. Exclusion criteria are patients with high caries activity/risk for caries and/or advanced periodontal disease. Patients who meet the criteria will be offered the opportunity to participate in the study. They will receive written information about the study design, clinical procedures and the materials and methods to be used. Patients who are interested will confirm their participation by a written consent. The patients will be offered an extended warranty for the crowns in case of failure. The study has been approved by the Regional Ethical Board in Lund, Sweden