Comparative Study of 3D-Printed Porous Titanium Alloy with Rod Designs of Three Different Geometric Structures for Orthopaedic Implantation

Porous titanium alloy is currently widely used in clinical treatment of orthopaedic diseases for its lower elastic modulus and ability to integrate with bone tissue. At the micro-level, cells can respond to different geometries, and at the macro-level, the geometric design of implants will also affect the biological function of cells. In this study, three kinds of porous scaffolds with square, triangular and circle rod shapes were designed and 3D printed. This study observed the proliferation and differentiation of MC3T3-E1 cells during surface culture of the three types of scaffolds. It also evaluated the characteristics of the three scaffolds by means of compression tests and scanning electron microscopy to provide a reference for the design of porous titanium alloy implants for clinical applications. The trends of cell proliferation and gene expression between the three types of scaffolds were observed after treatment with two inhibitors. The results show that the square rod porous scaffolds have the best proliferative and osteogenic activities, and these findings may be due to differences in piezo-type mechanosensitive ion channel component 1 (Piezo1) and Yes-associated protein (YAP) expression caused by the macro-geometric topography.