Modification of β-TCP/PLGA scaffold and its effect on bone regeneration in vivo

Abstract

In order to look for the best proportion of β-tricalcium phosphate(β-TCP) and poly(lactide-co-glycolide) (PLGA) we fabricated porous composites β-TCP/PLGA scaffold using freeze-drying method. Morphological characterization using scanning electron microscopy showed that the interconnected pore distribution was even and there was no significant difference with the increase of PLGA content. Moreover, the porosity, compressive strength and degradation in vitro were characterized. The fabricated scaffolds with increased PLGA in the composites β-TCP/PLGA scaffolds will get stronger mechanical property and better appearance, furthermore, get suitable environment for cells. According to the evaluation indexes for the tissue engineering scaffold, the group of scaffold (β-TCP/PLGA=6:4) was selected to evaluate the induced cell adhesion and proliferative ability of the scaffolds. Then as transplant embed into the bone critical defect sites on rats femur. The repairing processes of bone defect sites were characterized by X-ray analysis within 12 weeks. X-ray analysis showed that the bone defect sites all displayed the formation of callus obviously, In summary, our data suggest that the scaffold (β-TCP/PLGA=6:4) has a promising clinical future in regeneration of bone critical defects.

Keywords

modification / scaffold / freeze-drying / transplant / regeneration

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