Geometric Design and Mechanical Performance of Isotropic Bone Scaffolds

Abstract

The aim of bone tissue engineering scaffolds is achieving an isotropic porous structure with a superior strength, an appropriate elastic modulus, and a high specific surface area. However, meeting all these requirements is quite challenging. In this work, a mechanical metamaterial design strategy for isotropic bone scaffolds is proposed. Achieving isotropy does not require complex processes, and the calculations of homogenization show an improvement of 20% in Young’s modulus. The Ti6Al4V bone scaffold samples were fabricated using selective laser melting. Quasi-static compression tests were performed to confirm that the yield strength and stiffness of scaffolds match well with those of human bone. Finite element simulations further revealed the structure’s mechanical response mechanism. Computational fluid dynamics calculations demonstrated that the structure’s permeability is comparable with that of human bone trabeculae, and its large surface area facilitates osteogenic differentiation, thereby enhancing bone growth capabilities. This study aims to contribute to overcoming the constraints in the clinical applications of bone tissue engineering scaffolds.

Keywords: Isotropic bone scaffolds, Quasi-static compression, Finite element simulations, Permeability, Bone growth