Regenerative Efficacy of Supercritical Carbon Dioxide-Derived Bone Graft Putty in Rabbit Bone Defect Model

Bone defects can arise from numerous reasons, such as aging, tumor, trauma, infection, surgery, and congenital diseases. Bone grafts are commonly used as a substitute to fill the void and regenerate the defect. Due to its clean and green technology, the supercritical carbon dioxide (SCCO₂) extraction aided the production of bone grafts is a recent trend. The SCCO₂-derived bone graft has osteoconductive and osteoinductive properties along with excellent biocompatible, nontoxic, bioabsorbable, osteoconductive, and good mechanical properties; however, clinical usage during surgery is time-consuming. Therefore, we produced a putty material combining bone graft powder and acellular dermal matrix (ADM) powder and tested its regenerative efficacy in the critical defect in the rabbit model. The putty was found to retain the tubular structure. In addition, the putty depicted excellent stickiness and cohesiveness in both saline and blood medium. The bone regeneration of bone graft and putty was similar; both had excellent bone healing and regeneration of critical defects as evaluated by the X-ray, microtomography, hematoxylin-eosin, Masson trichrome, and alizarin red staining. Putty contains a less washout rate, good mechanical strength, and biocompatibility. In conclusion, the SCCO₂-derived moldable putty could be a promising easy-to-use alternative for bone grafts at present which might have real-world usage in orthopedics as a potential bone void filler and dental socket preservation.