A 3-year clinical follow-up study of a ceramic (Optec) inlay system

To evaluate the clinical quality of ceramic (Optec) inlays, the inlay production of 10 dentists, served by 3 dental laboratories, was examined independently by 2 calibrated examiners. Of the 57 patients with 205 inlays participating in the first examination, 47 patients with 145 remaining inlays participated in the 3-year follow-up reexamination. For 14 of the participants in the reexamination, altogether 21 inlays had fractured. The mean time in service before fracture was 26.4 months (range, 12-53 months). The inlays were rated using the California Dental Association (CDA) quality evaluation system. This examination showed that the mismatch of color had increased from the first examination to the reexamination and registered slightly roughened surfaces. As to anatomic form, a reduced number of inlays did not receive an excellent CDA rating at the reexamination. Visible evidence of ditching along the margin had increased by almost 50%, and an apparent discoloration of the margin between the restoration and the tooth structure was seen in 73% of the reexamined inlays, compared with 7% at the first examination.