Osteoneogenesis due to periosteal elevation with degradable and nondegradable devices in Gottingen Minipigs

Introduction: Periosteal distraction or elevation has been known as an experimental method to induce new bone formation. Although it uses the principles of distraction osteogenesis no further osteotomy is necessary. The purpose of this study was to test devices of different materials and to evaluate the point of origin of the new bone formation. Material & methods: On each calvaria of twelve male adult Gottingen Minipigs three devices were implanted. The materials used were degradable PDLLA (poly-m-lactide), PGA (polyglycolic acid) and nondegradable Ti (titanium). After a consolidation time of 2, 4 and 6 weeks days a total of 36 specimens were harvested. To identify the total amount of newly created bone, micro-CT and histological analysis were performed. Results: All degradable devices collapsed to a certain extent within the observation time but osteoneogenesis took place in all materials after a consolidation time of 2, 4 and 6 weeks after implantation above and under the devices. No statistical significant differences between the materials were found. However, most bone formation took place in the space under the periosteum and above the devices (p <0.001). Conclusion: Periosteal elevation can produce new bone formation with degradable devices, which derives from the periosteum and the underlying bone. In this interaction the periosteum seems to contain the larger share.