A variety of surgical techniques and tissue engineering strategies utilizing osteogenic potential of the periosteum have been developed for the repair of extended bone deficiencies. The aim of the present study was to assess the impact of an alternating protocol of periosteal distraction osteogenesis (PDO) on bone regeneration in an intraoral model. Eight adult, male Beagle dogs were used for the study. Two distraction devices were placed on each side of the mandible. After a 7-day latency period, distraction devices in all animals were manipulated at the rate of 0.5 mm for a total of 8 days. The pumping protocol in two test groups proceeded twice daily by alternating activation with relaxation. In the periosteal pumping/distraction (PPDO) group, the distraction screws were activated two times (at 12 and 24 h) and then turned back (at 36 h), and in the periosteal pumping (PP) group repeatedly activated and turned back (at 12 h). In the PDO group, only activation was performed once daily (positive control). Devices were left inactivated in the negative control (NC) group. The samples were harvested after 8 weeks of consolidation period and investigated by micro-CT and histological analysis. New mature, lamellar bone was formed over the pristine bone in all groups. PPDO and PDO groups showed more new bone area (NBA) compared to the PP (p < 0.001 and p < 0.001, respectively) and to the NC group (p = 0.032 and p = 0.031, respectively). Furthermore, greater NBA was found in the PP group than the NC group (p = 0.006). PDO demonstrated higher relative connective tissue area than the PPDO group (p = 0.005) and lower relative new bone volume than the NC group (p = 0.025). Pumping protocol of periosteal distraction may successfully induce the endogenous regeneration of the mandibular bone in dogs. Impact Statement Repair of extended bone defects impose a significant challenge to oral and maxillofacial surgeons. In this article, a principle of distraction osteogenesis was applied to stimulate bone regeneration in the mandible. A periosteum-based regeneration approach may represent a valuable step toward creating a significant volume of hard and soft tissues, without need for autogenous bone harvesting or application of biomaterials.
Keywords: animal models; bone; dental and periodontal; distraction osteogenesis; periosteum.