Osteogenesis, vascularization and osseointegration of a bioactive multiphase macroporous scaffold in the treatment of large bone defects.

Bone grafting remains the method of choice for the majority of surgeons in the treatment of large bone defects, since it fills spaces and provides support to enhance biological bone repair. Recently, we have reported our research on a bioactive multiphase macroporous scaffold with interconnected porous structures and nano-crystal surface microstructures that can release bioactive ions. Moreover, we demonstrated the excellent in vitro biological activity of the scaffold. In this study, we set out to evaluate the in vivo osteogenesis and vascularization of the scaffold in the treatment of large bone defects (10 mm radial bone defect in rabbits). In comparison with the control group, X-ray and micro-CT results at the 4th and 8th week post-surgery reveal that the bioactive scaffold displayed an enhanced level of new bone and vessel formation. Histological results at the same weeks indicated improved bone formation, osseointegration and new vessel ingrowth inside the bioactive scaffold. These findings establish a good foundation for the potential clinical validation of the bioactive macroporous biomaterial scaffold for use as a bone substitute or in tissue engineering.