Repair of compact bone critical sized defect with bone tissue engineering in rabbits

Abstract

The study was conducted to investigate the effect of bone tissue engineering comprised of combination of bone marrow-derived osteoblasts and corticocancellous bone graft in repairing 15 mm compact bone critical sized defect. Implant of corticocancellous bone graft alone served as group I. For the second group, bone marrow-derived osteoblasts seeded into scaffold of corticocancellous bone graft and the third group with no treatment served as the control group. Rabbits were euthanized on the fifth (only in group II) and the eighth week (all groups) postoperative. Radiographs were taken on the weekly interval. After euthanasia at the fifth and eighth weeks, the implants were harvested for, gross, histology and scanning electron microscope observations. In group I, new bone formation was only observed at the margin of defect and in the defect centre, hypertrophied chondrocytes was detected and major bone formation pattern was creeping substitution. New bone formation at margin of defect and osteogenesis at the centre were observed in the animals of group II, and the bone formation pattern included osteogenesis, osteoconduction, and osteoinduction. The most important finding of the control group was fibroblasts. The tissue engineering bone graft constructed by autogenous bone marrow-derived osteoblasts and corticocancellous bone graft was better than the graft alone in bone formation capability.