Fracture of Zirconia Abutments in Implant Treatments: A Systematic Review.

Abstract

PURPOSE The purpose of this systematic review was to identify and summarize clinical studies related to the fracture of zirconia abutments in implant treatments. MATERIAL AND METHODS Medline, Embase, and Cochrane library searches were performed and complemented by manual searches from database inception to February 11, 2018, for title and abstract analysis. RESULTS Initially, 645 articles were obtained through database searches. Fifty-three articles were selected for full-text analysis, and 15 studies met the inclusion criteria. The selected studies were analyzed regarding fracture rate, abutment-implant connection, time point of fracture, location of critical crack, causes, managements, and preventive measures with respect to zirconia abutment fracture. CONCLUSIONS Lower fracture rates were reported for internal connection with metal component (2-piece) zirconia abutments compared with external and internal full-zirconia connection (one-piece) zirconia abutments. Overpreparation and overload should be avoided in case of zirconia abutments.