A CLINICAL-EVALUATION OF PORCELAIN INLAYS

Sparse data are available concerning the survival rate of porcelain in lays or onlays to inform the dentist and address the expectations of p atients, A total of 25 posterior porcelain inlays were inserted by two dentists at a private Danish clinic; the time elapsed since cementati on was 20 to 57 months (average 40.4 months). Tooth preparations for M OD porcelain inlays were completed for 13 premolars and 12 molars but most did not include cuspal coverage. All inlays were constructed at t he same commercial dental laboratory and according to the manufacturer 's recommendations; they were etched and treated with silane before th ey were cemented. The cementation included etching of cavosurface enam el and treatment of the dentin with a dentinal bonding system. A thin layer of composite resin luting agent was applied to the tooth prepara tion before the porcelain inlays were cemented. The first 10 porcelain inlays were cemented with a light-curing composite resin cement and t he remaining 11 with a dual curing composite resin cement. Twelve of t he 25 porcelain inlays failed and were replaced during the observation period. Ten failures were due to a fracture of the inlay, one was cau sed by secondary caries, and the final failure was attributed to a mar ginal gap between the inlay and proximal tooth surface. Porcelain inla ys cemented with light curing composite resin exhibited more failures (p = 0.05) than those cemented with dual-curing composite resin. In ad dition, more failures (p = 0.07) were recorded among inlays inserted i n molars than among those in premolars.