Enhanced bone regeneration by gelatin-β-tricalcium phosphate composites enabling controlled release of bFGF

The objective of this study was to investigate the feasibility of biodegradable gelatin-β-tricalcium phosphate (β-TCP) composites as a cell scaffold and controlled-release carrier of basic fibroblast growth factor (bFGF) suitable for inducing bone regeneration at a segmental bone defect. The composite of gelatin sponge and β-TCP granules had an interconnected pore structure with an average size of 340 µm. The composite provided the controlled release of bFGF over 2 weeks. Segmental, critical-sized, bone defects of 20 mm length were created in the ulnas of New Zealand white rabbits and the gelatin-β-TCP composites, with or without incorporated bFGF, were implanted into the defects. Bone regeneration and β-TCP resorption profiles were evaluated by microcomputed tomography scanner analysis and haematoxylin and eosin staining. The composites incorporating bFGF promoted significantly higher bone regeneration at the defect site as compared to the bFGF-free composites. The controlled release of biologically active bFGF from the composites may possibly be achieved through the biodegradation of the composites, resulting in the promotion of bone regeneration. We conclude that the biodegradable gelatin-β-TCP composite is a promising scaffold for bone regeneration that enables the controlled release of bFGF.