IADR Abstract Archives
Prediction of Flexural Strengths of Composite Resins by in silico-analysis
Objectives: Recently, usage of composite resins (CR) for posterior restorations have been greatly increasing. For further improvement of the mechanical properties of CR, optimization of contents, sizes, types, or geometric layouts of fillers are required. The aim of this study was to assess the feasibility to predict flexural strengths of CR in silico with combination of mathematical model and three-dimensional finite element analysis (3D-FEA).
Methods: The models of flexural strength test specimens of CR following ISO4049:2009 (25 × 2 × 2 mm) and the rods (ϕ2 × 4 mm) to give a three-point loading were designed by CAD software (Solidworks Simulation 2011). CR was composed of silica filler and matrix, their Young’s moduli and Poisson’s ratios being set as 72 GPa, 0.16 and 3 GPa, 0.45, respectively. The volume contents of filler ranged from 0 to 100%. Calculation of Young’s moduli and Poisson’s ratios of CR were conducted by modified McGee-McCullough model. In 3D-FEA, flexural strengths were defined when the fracture loads exceeded maximum principal strain 0.01357, which was calculated from monomer compositions of Bis-GMA/TEGDMA. Using the experimental CR containing Bis-GMA/TEGDMA and silica filler, flexural strengths were measured according to ISO4049:2009 and compared with the values determined by in silico analysis.
Results: In in silico model, two phase increase in flexural strengths of CR was observed, with abrupt increase beyond 80% filler contents. The flexural strengths of experimental composites containing 31.2, 40.2, and 50.3% filler were 114.8±10.5, 128.6±6.9, and 138.8±4.4, and significantly correlated with those obtained in silico (113.5, 134.5, and 170.5 MPa; Pearson’s correlation test, r = 0.970, p < 0.01).
Conclusions: The in silico analytical model established in this study was found to be effective to estimate the flexural strengths of CR containing silica filler, suggesting its possible usefulness for prediction of mechanical properties of CR.
Methods: The models of flexural strength test specimens of CR following ISO4049:2009 (25 × 2 × 2 mm) and the rods (ϕ2 × 4 mm) to give a three-point loading were designed by CAD software (Solidworks Simulation 2011). CR was composed of silica filler and matrix, their Young’s moduli and Poisson’s ratios being set as 72 GPa, 0.16 and 3 GPa, 0.45, respectively. The volume contents of filler ranged from 0 to 100%. Calculation of Young’s moduli and Poisson’s ratios of CR were conducted by modified McGee-McCullough model. In 3D-FEA, flexural strengths were defined when the fracture loads exceeded maximum principal strain 0.01357, which was calculated from monomer compositions of Bis-GMA/TEGDMA. Using the experimental CR containing Bis-GMA/TEGDMA and silica filler, flexural strengths were measured according to ISO4049:2009 and compared with the values determined by in silico analysis.
Results: In in silico model, two phase increase in flexural strengths of CR was observed, with abrupt increase beyond 80% filler contents. The flexural strengths of experimental composites containing 31.2, 40.2, and 50.3% filler were 114.8±10.5, 128.6±6.9, and 138.8±4.4, and significantly correlated with those obtained in silico (113.5, 134.5, and 170.5 MPa; Pearson’s correlation test, r = 0.970, p < 0.01).
Conclusions: The in silico analytical model established in this study was found to be effective to estimate the flexural strengths of CR containing silica filler, suggesting its possible usefulness for prediction of mechanical properties of CR.