AIM: to observe the changes in dental pulp and periodontal tissues under the application of distraction osteogenesis using tooth-attached intraoral distracter.

目的：研究使用牙支抗式牵张器行上颌骨牵张成骨术后牙髓和牙周的组织学改变。

Objective to introduce the new type of MS - 1 internal mandibular distracter and its applications and to investigate the advantage or disadvantage of the device through an experimental study in dogs.

目的介绍自行开发的内置式下颌骨骨牵引延长器，探讨其在动物实验中的应用方法与可行性。