Design and mechanical properties analysis of heterogeneous porous scaffolds based on bone slice images

Bone tissue engineering plays an extremely important role in the clinical treatment of bone defects. Porous scaffold is one of the three essential factors of bone tissue engineering, and its structural design has attracted more and more attention . At present, most of the design methods of porous scaffolds focus on uniform porous scaffolds with periodic and regular pore structures. However, periodic and regular pore structure cannot comprehensively and accurately simulate the microstructures and mechanical properties of natural bone. To address this problem, based on bone slice images and VT (Voronoi-Tessellation) method, this article proposed a design method of HPS (Heterogeneous Porous Scaffolds) with bionic pore structure and controllable porosity. The FDM (fused deposition modeling) printing technology was applied to fabricate HPS with different porosities, and the mechanical properties of the HPS were analyzed by experiments. The research results illustrate that the HPS constructed by the design method proposed in this article have good controllability, and their internal pore structures are highly similar to those of natural bone, which have biomimetic characteristics. The mechanical property analysis illustrate that the stiffness and compressive strength of HPS decrease with the increase of porosity, in addition, the heterogeneous pore distribution makes HPS have the characteristics of non-concentrated and discontinuous damage distribution. This study provides a new idea for the design of porous scaffolds and a theoretical basis for the bionic design of HPS.