Clinical evaluation of all-ceramic onlays: A 4-year retrospective study

Purpose: The aim of the present study was to evaluate the clinical outcome of extensive Empress onlays retained with resin-bonded cement. Materials and Methods: One hundred thirty extensive ceramic onlays were placed in premolar and molar regions in 91 patients treated by 2 general practitioners between 1997 and 2000. Seventy-seven percent of the constructions were luted with chemically cured resin composite cement and 23% were luted with dual-cured resin cement. Fifty-nine patients with 81 restorations were clinically evaluated independently by 2 calibrated examiners using the California Dental Association protocol. The mean time in function for all restorations at examination was 49 months. Results: Seventy-five (93%) onlays were still in function after 4 years. Six onlays (7.3%) had failed; 1 had lost retention as a result of caries, and 5 had fractured. All failures were in molar regions. Conclusions: Ceramic onlay therapy is an acceptable treatment alternative over a 4-year period, but further long-term data are necessary before this treatment should be considered for general dental practice.