Enhanced osteogenesis of honeycomb β-tricalcium phosphate scaffold by construction of interconnected pore structure: An in vivo study.

Abstract

Pore structure plays an important role in the in vivo osteogenesis for bone repair materials. In this study, honeycomb β-tricalcium phosphate (β-TCP) scaffolds were prepared by extrusion method, and gelatin microspheres were used as porogens to modify the pore structure of the scaffolds. The honeycomb β-TCP scaffolds were characterized by channel-like square macropores and unidirectional interconnection. To improve the pore interconnectivity of the scaffold, the spherical pores were formed in the channel walls by burning off the gelatin microspheres. Compared with unidirectional honeycomb β-TCP scaffold, the honeycomb β-TCP scaffold with interconnected pore structure had significantly higher porosity and faster degradation rate, at the expense of the mechanical strength. The in vivo assessment results demonstrated excellent osteogenesis of the honeycomb scaffolds. Moreover, the honeycomb β-TCP scaffold with interconnected pore structure markedly promoted new bone formation in comparison with the unidirectional honeycomb β-TCP scaffold. This work provides a new approach to prepare scaffolds with interconnected pore structure, and the honeycomb β-TCP scaffold with interconnected pore structure is expected to serve as an efficient bone repair material.