Analysis of reasons for failure of chair ⁃ side CAD/CAM ceramic restorations

Abstract

Objective To investigate the failure reasons of all⁃ceramic restorations fabricated with chair⁃side CAD⁃ CAM technology (CEREC®) and to improve the clinical survival of all⁃ceramic restorations. Methods All⁃ceramic single ⁃tooth restorations of CEREC® in stomatology hospital of Jiangsu province between 2013 and 2016 were summarized. By clinical examination and CEREC Biogeneric surveying, the failure reasons and related restoration types were evaluated. These results were analyzed with Chi ⁃square test and Spearman correlation analysis. Results A total of 61 cases with restoration types of 11 inlays, 38 onlays, 2 endocrowns, and 11 all⁃crowns, resulted in a failure rate of 5.4% in all⁃ceramic single⁃tooth restorations in 1⁃4 years follow⁃up. The reasons for failure included ceramic fracture (n＝33), debonding (n＝ 13), tooth fracture (n＝15), which attributed to thin ceramic thickness (n＝27), acute line angle (n＝6), insufficient enam⁃ el bulk (n＝3), insufficient retention type (n＝10), insufficient resistance type (n＝15). Conclusion The most common reason for failure in CEREC® restorations was insufficient preparation space in occlusal surface.

Keywords

• Chair⁃side CAD / CAM，
• Risk of failure，
• All⁃ceramic restoration，
• Ceramic fracture，
• Onlay，