Biosilicated collagen/β-tricalcium phosphate composites as a BMP-2-delivering bone‐graft substitute for accelerated craniofacial bone regeneration

Abstract

Abstract Background Bioceramic β-tricalcium phosphate (β-TCP) is used as a bone-grafting material and a therapeutic drug carrier for treatment of bone defects in the oral and maxillofacial regions due to the osteoconductivity and biocompatibility. However, the low mechanical strength and limited osteoinductivity of β-TCP agglomerate restrict bone regenerating performance in clinical settings. Methods Herein, a biomimetic composite is proposed as a bone morphogenetic protein-2 (BMP-2)-delivering bone graft substitute to achieve a robust bone grafting and augmented bone regeneration. Results The sequential processes of brown algae-inspired biosilicification and collagen coating on the surface of β-TCP enable the effective incorporation of BMP-2 into the coating layer without losing its bioactivity. The sustained delivery of BMP-2 from the biosilicated collagen and β-TCP composites promoted in vitro osteogenic behaviors of pre-osteoblasts and remarkedly accelerated in vivo bone regeneration within a rat calvarial bone defect. Conclusions Our multicomposite bone substitutes can be practically applied to improve bone tissue growth in bone grafting applications with further expansion to general bone tissue engineering.

Keywords

• Osteoinductive bone substitute
• Collagen/β-TCP composite
• Biosilicification
• Bone morphogenetic protein-2 (BMP-2)
• Biomimetic materials