Allogeneic Osteoblasts Combined with β-Tricalcium Phosphate to Repair of Bone Defect

Treatment of large bone defects represents a great challenge in orthopedic surgery. Although there are several methods for bone reconstruction, they all have specific indications and limitations. The use of artificial bone graft substitutes has increased as the surgical applications widely and the availability of allograft bone declined. As a bone scaffold material, β-tricalcium phosphate (β-TCP) has good biocompatibility, osteoinductive, and biomechanical properties. Osteoblast is the main cell in bone formation, and plays a key role in bone growth, bone metabolic balance, bone mass maintenance and bone damage repair. The present study was to evaluate the osteoblast compounded with β-TCP in repairing rabbit radial defects. A total of 30 rabbit radial defect models were made and divided into two groups in random. Experimental group was repaired with the compound of allogeneic osteoblast and β-TCP; control group with β-TCP. The new bone formation of each group was observed and assessed by X-ray and histopathological analysis at weeks 4, 8, 16 after implantation for evaluation of the bone repairing effect. Results showed that with the repair time, the experimental group appeared to complete bone defect repair gradually. By the end of 16 weeks, the X-ray showed that the bone callus between the scaffold and the host was completely ossified, and bone defects were completely repaired in the experimental group. Histopathological observation showed continuous cortical bone formed in the defect area, and canal recanalization realized in the experimental group. Additionally, the repair effect in the experimental group was better than that in the control group at different time points (P < 0.01). It was suggested that the osteoblast/β-TCP compound had the better effects on guiding bone regeneration and preventing from nonunion.