Le Fort Ⅲ型截骨中位牵引矫正面中份发育不全

目的探索使用中份骨骼均衡前移的牵引技术，以矫正面中份后缩畸形。方法牵引系统由面弓、牙科正畸用的橡皮圈和经鼻孔插入的骨内承力牵引装置组成。对18岁以上的严重面中份发育不全畸形的患者3例，行Le Fort Ⅲ型截骨。显露两侧梨状孔缘，用粗裂钻在梨状孔的外下缘外侧约8mm处钻孔，斜向穿过上颌窦前壁和鼻腔侧壁的骨质达下鼻道。经双侧鼻孔引入骨内承力牵引装置的挂钩，将挂钩插入梨状孔缘的骨孔内。手术后第3天用连接于面弓和骨牵引钩的正畸橡皮圈进行牵引。结果患者面容和咬合关系完全恢复正常，面部上、中、下各部的前后关系协调，鼻梁及鼻下部挺拔。结论Le Fort Ⅲ型截骨后弹力牵引能够有效地矫正严重面中份发育不全畸形。新的牵引技术牵引力点适中，能够使面中份骨骼平衡前移；避免对牙齿牵拉所造成的不利改变；利用鼻孔的自然结构，不留可见瘢痕。

Le Fort Ⅲ osteotomy and medium position distraction for mid-facial hypoplasia

OBJECTIVE: To probe the possibility of distraction osteogenesis for correction of mid-facial hypplasia using a new technique. METHODS: The distraction system of mid-facial skeleton consisted of a face-bow, the elastic loops and a device that hitched to bone holes made in the aperture rim. Flllowing Le Fort III osteotomy, a bone hole was drilled at each side of the external-inferior rim of the aperture by a dental bur. The traction device was hitched to the holes through the nostrils. Distraction began three days postoperatively, with the force adjusted dependently upon the rate of progress. When the skeleton reached to the planed position, distraction was retained with a minor force for 8 weeks. Three adults with mid-facial hypoplasia underwent this treatment. RESULTS: The mid-facial skeleton showed a balanced advancement. The patients' facial contour and occlusal relationship recovered completely. CONCLUSIONS: Patients with severe mid-facial hypoplasia could be corrected ideally by the new technique, with balanced advancement of mid-facial skeleton, minor trauma. The design of distraction system was reasonable. The manipulation of the procedure was easy.