Fracture resistance of computer‐aided design/computer‐aided manufacturing‐generated composite resin‐based molar crowns

• DOI: 10.1111/eos.12173
• Publication Date: 2015-02-16T05:56:58Z
• Authors: Akio Harada; Keisuke Nakamura; Taro Kanno; Ryoichi Inagaki; Ulf Örtengren; Yoshimi Niwano; Keiichi Sasaki; Hiroshi Egusa
• Keywords: Dental Stress Analysis; Ceramics; Surface Properties; Polyurethanes; micro-CT; Composite Resins; CAD/CAM; Dental Materials; 03 medical and health sciences; 0302 clinical medicine; Materials Testing; Humans; Dental Restoration Failure; Pliability; composite resin; Crowns; X-Ray Microtomography; fracture resistance; VDP::Medisinske Fag: 700::Klinisk odontologiske fag: 830; Dental Porcelain; Molar; VDP::Medical disciplines: 700::Clinical dentistry disciplines: 830; Dental Prosthesis Design; Computer-Aided Design; Methacrylates; lithium disilicate; Stress, Mechanical; Porosity; Algorithms

The aim of this study was to investigate whether different fabrication processes, such as the computer-aided design/computer-aided manufacturing (CAD/CAM) system or manual build-up technique, affect fracture resistance composite resin-based crowns. Lava Ultimate (LU), Estenia C&B (EC&B), and lithium disilicate glass-ceramic IPS e.max press (EMP) were used. Four types molar crowns fabricated: CAD/CAM-generated (LU crowns); manually built-up monolayer (EC&B-monolayer layered (EC&B-layered EMP Each type crown cemented dies tested. EC&B-layered showed significantly lower compared with LU crowns, although there no significant difference in flexural strength toughness between EC&B materials. Micro-computed tomography fractographic analysis that decreased probably resulted from internal voids introduced by layering process. There among LU, EC&B-monolayer, Both loads >2000 N, which is higher than bite force. Therefore, without defects, may be applied regions sufficient resistance.