Prediction of mechanical behavior of 3D bioprinted tissue-engineered scaffolds using finite element method (FEM) analysis

Three-dimensional (3D) printing can be a promising tool in tissue engineering applications for generating tissue-specific 3D architecture. The 3D printing process, including computer-aided design (CAD), can be combined with the finite element method (FEM) to design and fabricate 3D tissue architecture with designated mechanical properties. In this study, we generated four types of 3D CAD models to print tissue-engineered scaffolds with different inner geometries (lattice, wavy, hexagonal, and shifted microstructures) and analyzed them by FEM to predict their mechanical behaviors. For the validity of computational simulations by FEM, we measured the mechanical properties of the 3D printed scaffolds. Results showed that the theoretical compressive elastic moduli of the designed constructs were 23.3, 56.5, 67.5, and 1.8 MPa, and the experimental compressive elastic moduli were 23.6 +/- 0.6, 45.1 +/- 1.4, 56.7 +/- 1.7, and 1.6 +/- 0.2 MPa for lattice, wavy, hexagonal, and shifted micro-structures, respectively, while maintaining the same construct dimension and porosity. In addition, van der Waals hyperelastic material model was successfully utilized to predict the nonlinear mechanical behavior of the printed scaffolds with different inner geometries. These findings indicated that the CAD-based FEM prediction could be used for designing tissue-specific constructs to mimic the mechanical properties of targeted tissues or organs.