Bone Healing Process Around Distraction Implants Following Alveolar Distraction Osteogenesis: A Preliminary Experimental Study in Dogs

In this study, a new type of distraction implant (DI) that could be transformed into a prosthetic implant after distraction was applied to augment the alveolar ridge, and the bone response around it was observed in six dogs. Two DIs were placed into the lateral edentulous submandibular ridge after osteotomy. The DIs were left to integrate into the bone after 8 days of distraction at a rate of 1 mm per day. Specimens were obtained at 5, 8, and 12 weeks after distraction. Radiopacity of the regenerated bone increased steadily during the consolidation period. After 12 weeks, homogeneous bone density was observed. Histologic examination showed osseointegration of the whole DI in the region of the threads in the native bone and in the regenerated area 12 weeks later. These results suggest that simultaneous bone regeneration in a distracted gap and osseointegration of DIs in an augmented alveolar ridge can be achieved. The overall treatment time could be shortened significantly with this method.