Retrospective survival analysis of 110 lithium disilicate crowns with feather-edge marginal preparation.

Purpose To evaluate the clinical performance of lithium disilicate (LiDiSi) crowns with a feather-edge finish line margin over a 9-year period. Materials and methods In total, 110 lithium disilicate crowns, 40 anterior (36.3%) and 70 posterior (63.7%), were cemented with resin cement after fluoridric acid and silane surface treatment and observed by a different clinician. The data were analyzed using the Kaplan-Meier method. The clinical evaluation used the California Dental Association (CDA) modified criteria after recalling all patients between January and April 2013. Results Two crowns had failed and were replaced due to core fractures. One chipping occurred on a first molar and the ceramic surface was polished. The overall survival probability was 96.1% up to 9 years, with a failure rate of 1.8%. Conclusion In this retrospective analysis, lithium disilicate with a vertical finish line used in single-crown restorations had a low clinical failure rate up to 9 years.