Fixed Dental Prostheses and Single-Tooth Crowns Based on Ceria-Stabilized Tetragonal Zirconia/Alumina Nanocomposite Frameworks: Outcome After 2 Years in a Clinical Trial

Purpose: This clinical trial tested bilayered restorations based on ceria-stabilized tetragonal zirconia/alumina frameworks veneered with feldspathic ceramic. Materials and Methods: A total of 67 crowns and 40 fixed dental prostheses (FDPs) were luted in 57 patients with self-etching/self-adhesive composite resin cement. Dental status and integrity of restorations were evaluated at 2 weeks, 6 months, and then annually. Results: A total of 66 crowns and 36 FDPs (88% posterior) survived for success rates of 93.4% for crowns and 89% for FDPs at 2 years. In particular, 11 cohesive ceramic chippings were observed in 5 crowns and 6 FDPs. Conclusion: The material allows excellent marginal adaptation. Susceptibility to veneering failures might be due to framework design and the necessities of esthetics.