Fracture origin and crack propagation of CAD/CAM composite crowns by combining of in vitro and in silico approaches. (December 2020)

• Record Type: Journal Article
• Authors: Yamaguchi, Satoshi; Katsumoto, Yu; Hayashi, Kimiko; Aoki, Maika; Kunikata, Miwa; Nakase, Yutaro; Lee, Chunwoo; Imazato, Satoshi
• Is Part Of: Journal of the mechanical behavior of biomedical materials. Volume 112(2020)
• Publication Date: 2020-12
• Subjects: CAD/CAM resin composites -- Fracture initiation -- Crack propagation -- Compressive tests -- Finite element analysis; Biomedical materials -- Periodicals; Biomedical materials -- Mechanical properties -- Periodicals; Biomedical materials; Biomedical materials -- Mechanical properties; Periodicals; Electronic journals; 610.28
• DOI: 10.1016/j.jmbbm.2020.104083
• Languages: English
• ISSNs: 1751-6161

Abstract

Abstract: Purpose: Fractographic analysis has been used to investigate the fracture behavior of Computer-aided design/computer-aided manufacturing (CAD/CAM) composite crowns by subjecting them to compression tests. However, it is difficult to investigate details of the fracture, including its initiation and propagation, using in vitro tests. The aim of this study was to determine the fracture origins and the order of crack initiation of CAD/CAM composite crowns using in silico nonlinear dynamic finite element analysis (FEA). Material and methods: The following materials were used: Cerasmart (CS), Katana Avencia Block (KA), and Shofu Block HC (HC) as CAD/CAM crowns, Panavia SA Cement Plus (SA) as a luting material, and Clearfil DC Core Plus (DC) as an abutment. The elastic moduli and fracture strain of each material were obtained from the stress–strain curve of in vitro three-point bending tests. The fracture origins and order of crack initiation of the materials were determined by in silico nonlinear dynamic compression analysis. Load-displacement curves were statistically compared with the results of the in vitro compression tests (Pearson's correlation test, α = 0.05). Results: The nonlinear dynamic FEA demonstrated that crack initiation was primarily observed near the lingual side of the CAD/CAM crowns and immediately propagated to the central fossa. The models were fractured following the in vitro fracture strains, showing the same order for the products tested (CS/KA/HC, SA, and DC). Load-displacement curves with the use of CS, KA, and HC were significantly correlated to the corresponding in vitro compression tests results (CS: r = 0.985, p < 0.05, KA: r = 0.987, p < 0.05, and HC: r = 0.997, p < 0.05). Conclusions: The in silico model established in this study clarified the crack initiation of the CAD/CAM composite crowns and the order of crack initiation among the investigated products, suggesting that the present approach is useful for analyzing the fracture behavior of CAD/CAM composite crowns in detail. Graphical abstract: Image 1 Highlights: Crack initiation of CAD/CAM composite crowns was assessed. Order of crack initiation of the crown specimens was analyzed. Crack initiation was observed near the lingual side of the crowns. Fracture patterns of the in vitro / in silico compression tests were matched. In silico load-displacement curves were separated into two phases.