Development of the distraction osteogenesis model for rat mandibular inferior border and alveolar bone

Abstract

[한글]

[영문]Osteogenic distraction is defined as surgical procedure which creates new bone and adjacent other tissues including gingiva, skin, muscle, tendon, blood vessels and nerves by incremental traction of osteomized bone edges. By virtue of it’s advantages, treatment effects of distraction osteogenesis on patients have been reported. In recent, even the mechanism of distraction osteogenesis has been extensively applied to alveolar bone area as an alternative to the traditional treatment. Tremendous development of the technique has been achieved, but much of molecular events involved in the process remained still questionable. The aim of this study is to establish an experimental rat model for distraction osteogenesis on mandible and alveolar bone concurrently for investigating histologic and radiographic analysis and to develop the device for various conditions of distraction. The results of this study were as follows.1.Micro CT analysis was performed for the anatomical structure of rat mandible and provided the guides for the location and design of osteotomy and positioning the bone screws stabilizing the distraction device. 2.The rat distraction osteogenesis model for mandibular inferior border and alveolar bone was successfully established on the basis of the protocols used in this study. The protocols contain 5 days of latency period, distraction rate of 0.20 mm/day, at a single session, and 4 weeks of consolidation phase. 3.New bone formation of the rat model occurred by combination of two modes. Intramembranous ossification was predominant at the end of distraction period, while endochondral ossification was observed at the center of distraction gap at the end of 4 weeks of consolidation period.The mandibular inferior border and alveolar distraction model for rats was successfully established in this study. This model can be applied to various conditions related to the distraction osteogenesis and provide knowledge for improvements of distraction osteogenesis treatment for patients.