A Multi-Scale Computational Model to Predict the Performance of Cell Seeded Scaffolds with Triply Periodic Minimal Surface Geometries

Bone scaffolds are required to replace the painful and dangerous process of bone grafting, currently the gold standard for treating open bone fractures. Tissue engineering scaffolds work best when there is a high amount of surface area for biological cells to attach. Triply Periodic Minimal Surface (TPMS) geometries offer high ratios of surface area per volume. However, it is not yet clear which TPMS cell type would yield the fastest bone growth rate. In this study, we used a three-dimensional multi-scale model to predict the performance of scaffolds with four TPMS unit cell types (Primitive, Gyroid, Diamond and Lidinoid). At the micro-scale, the model simulates curvature-dependent tissue growth, while at the macro-scale the model uses FEA to ensure the construct stiffness is acceptable. The Lidinoid unit cell type was found to yield the most bone growth after 40 days while also ensuring an acceptable scaffold stiffness.