Design and research of a bredigite bone repair scaffold.

Purpose: The fluid shear stress (FSS) generated by fluid flow after scaffold implantation is an important factor affecting the osteogenic ability of scaffolds and the proliferation and differentiation of osteoblasts are also affected by FSS. When the bone injury occurs, the blood flow at the defect changes from laminar flow to turbulent flow. Consequently, it is essential to employ a numerical simulation method that accurately reflects the actual conditions to study and analyze the surface FSS experienced by scaffolds and cells, thereby enhancing the osteogenic properties of the scaffolds. Methods: In this research, nine scaffolds with different structures and pore sizes were designed. The two-way fluid-structure interaction (FSI) method was used to evaluate scaffolds' internal flow field velocity and the surface FSS of scaffolds and cells. Results: The results show that the velocity distribution of different scaffolds is basically the same. FSS on the scaffold surface and FSS on cell surface decreased with the increase of scaffold pore size. FSS accepted by cells was much larger than that received by scaffolds, and FSS was distributed in a stepped pattern on the cell surface. Conclusions: Based on the FSS of the scaffold and cell surface, the triangle-600 and triangle-800 scaffolds have better osteogenic differentiation ability. This provides a more practical strategy for tissue engineering to design better scaffolds.