Histologic Evaluation of Regenerated Bone in Distraction Osteogenesis Technique and Autogenous Bone Graft in Sheep

Introduction: The success rate of implantation in augmented ridges depends on the quality of regenerated bone. Histologic studies are needed to stablish bone formation in these techniques. This study was performed to compare histologic features of regenerated bone in Distraction osteogenesis and autogenous bone graft in ridge augmentation. Materials & Methods: This pilot study was done in mandiubular dental pads of sheep. Distraction osteogenesis was performed on one side and the other side was augmented using autogenous bone graft. Posterior pad in each side was used as control. After 8 weeks, reentries were performed and sheep were sacrificed. Bone tissue samples of each area were prepared for histologic evaluation and comparison. Results: In control area, only normal bone tissue was observed and there was no evidence of fibrous or cartilage tissue. Bone trabecules in lamellar form were accompained with resting zones with less inactive fibrous tissue. There was moderate to severe chronic inflammation. In distraction zone, mature woven and lamellar bone was observed in some vascular and cellular stroma containing collagen fibers and blood vessels. There was less inflammation. In some area there was some cartilage. Conclusion: In spite of some advantages for autogeuous bone graft, Due to its complications, technical difficulties, bone resorption and unfavourable histologic features compared with distraction, distraction osteogenesis technique could be used for ridge augmentation.