A randomized 5-year clinical evaluation of 3 ceramic inlay systems.
The present follow-up study aimed to evaluate the clinical quality and longevity of 3 ceramic inlay systems and compare them with gold inlays.
                Twenty patients were treated with one Cerec, one Mirage, one Empress, and one gold inlay, respectively, inserted in a randomly selected order in the mandible. The inlays were examined independently by 2 calibrated examiners immediately after and 1, 3, and 5 years after luting. The inlays were rated using the California Dental Association (CDA) quality evaluation system.
                Two Empress inlays required replacement because of fracture between examination (Ex) 1 and Ex 2, and 2 Empress inlays were fractured between Ex 3 and Ex 4. One Cerec inlay had to be recemented after 3 months, and one Cerec inlay fractured between Ex 3 and Ex 4 and was replaced with a gold inlay. Examination showed that the mismatch of color increased from 15% to 50% between Ex 1 and Ex 4 for all ceramic systems. Visible evidence of ditching along the margin increased from 5% at Ex 1 to 70% at Ex 4, and an apparent discoloration of the margin between the tooth and the restoration was seen in 0% to 5% at Ex 1 compared to 30% to 55% at Ex 4.
                Eight percent of the ceramic inlays were fractured during the follow-up period of 5 years. Based on the criteria of the CDA quality evaluation system, 92% of the 60 ceramic inlays and 100% of the 20 gold inlays were rated satisfactory 5 years after luting.
There is no strong evidence available to support any differences in the clinical performance of ceramic inlays and other posterior restorations. There is a limited number of well-designed clinical trials within this research area. Greater attention to the design and reporting of studies should be given to improve the study quality of ceramic restoration trials.