牙支抗进行羊下颌骨延长的初步实验研究

Mandibular advancement using tooth-supported distraction osteogenesis device in goat

目的 :观察自制的牙支抗骨延长装置进行羊下颌骨延长的实用性和有效性。方法 :将 8只 7～ 9月龄羊分为 4组 ,每组 2只 ,在下颌第 2和第 3前磨牙之间行骨皮质切开并造成青枝骨折后 ,将自制的颌骨延长装置粘固于牙齿上 ,术后 5 d开始加力 ,每次 0 .2 5 mm,每日 2次。在开始加力后分别于第 8、16、32、48天时将动物处死 ,标本进行大体观察、血管造影、X线检查。结果 :大体标本显示 ,在下颌第 2、第 3前磨牙之间出现明显的骨延长区域 ,其表面由正常的牙龈组织覆盖。X线检查结果表明随着时间的延长 ,新骨不断形成并趋于成熟 ,加力结束后保持 16 d的标本下颌骨连接性就已恢复 ,支抗基牙有所倾斜 ,周围其他组织未见明显不良反应。血管造影显示 :在骨延长的各个阶段 ,下齿槽动脉通畅良好。结论

砄bjective: To observe the effects of an introral tooth supported distraction device on advancement mandible of goat.Methods:8 goats (7～9 months of age)were divided into 4 groups with 2 goats in each.After bilateral mandibular cortitomy between the second and third premolars,selfproduced intraoral tooth supported distraction devices were cemented onto the second and third premolars.5 days after operation,the distraction devices began to be activated 0.25 mm every 12 hours to advance 8 mm of the anterior segment in 16 days.The animals were sacrificed on day 8,16,32,48 respectively since activation,then gross sample inspection,vascular contrast examination and radiographic examination were performed.Results:Obvious bone lengthening was observed between the second and third premolars with coverage of normal gingival tissue.Radiography showed that new bone gradually formed and matured.There was no obvious side effect except that the anchoring teeth showed some titling.Vascular contrast examination showed that the lower alveolar arteries were continuing.Conclusion:Tooth supported DO device can effectively advance mandible of goat.