内置式颌骨牵引器的研制及临床研究

目的 自行研制系列内置式合骨牵引器并运用于动物实验及临床，观察其结果。方法 共研制了7种17个规格的内置式颌骨牵引器，进行生物力学测试后，在16只恒河猴、12只山羊的3组动物实验中分别使用40个牵引器；临床对7个病种68例疑难牙颌面畸形患者试用82个牵引器，观察其组织相容性、稳定性及其对新骨生成的影响。结果 7种牵引器均使用国家核准生产的国产人体用钛合金材料制成。经拉力扭力试验，其承载拉力＞7．8kgf，扭力＞5．0kgf。传动部分采用国际2级级螺纹传动，转动灵活、无死点，进退间隙＜0．1mm。两固定架间的横向间隙＜0．1mm，两导向杆的平行度在0．05mm以内。动物实验及临床研究结果表明，无组织排异反应，早期病例中有2例牵引器在牵引过程中方向结折断。后作了改进设计。大部分实验动物及临床病例牵引过程顺利，成骨良好。结论 上述系列内置式颌骨牵引器可满足不同颌骨牵引成骨的临床及实验研究使用，为在我国推广应用内置式颌骨牵引成骨技术打下了基础。

Development of internal distractors for jaws: experimental and clinical studies

OBJECTIVE: To introduce a series of internal distractors developed by the authors and results of experimental study and clinical trials. METHODS: Based on the demand of clinical use and experimental studies, 7 kinds and 17 types of internal distractors were developed. Required biomechanics were evaluated and animal studies were undertaken in 16 Rhesus monkeys and 12 goats with 40 distractors. Clinically, 68 Patients with 7 kinds of severe dento-gratho-facial deformities were treated with 82 distractors and the histocompatibility, stability, influence on new bone formation were evaluated. RESULTS: The 7 kinds of distractors were State-approved products made of Titanium alloy and permitted for use in human. The pull and twist force tests demonstrated that the loading capability of them were larger than 7.8 kgf and 5.0 kgf respectively. The domestic made Grade II screw was used to transmit the moving, it was nimble, without dead point, and with a forward-backward space of < 0.1 mm. The horizontal space in between the two fixing parts was < 0.1 mm. The parallel degree of the two direction-guide rods was within 0.05 mm. Animal and clinical studies demonstrated that there was no rejection response of the tissues. There were fractures of the direction-guide rods in two early cases, the design was improved then. Other results both experimentally and clinically were satisfactory with good osteogenesis. CONCLUSIONS: This series of domestic made internal distractors can be used satisfactorily in distraction osteogenesis for various kinds of jaw deformities. The successful production of these distractors will provide a good foundation to popularize the internal distraction osteogenesis of the jaws.