牵引成骨技术在矫治唇腭裂继发重度上颌发育不全畸形中的应用

目的　探讨颌骨牵引成骨技术在矫治唇腭裂继发重度上颌发育不全畸形中的应用价值及不同牵引方式的选择。方法　 8例患者 (男 6例 ,女 2例 ) ,年龄 11～ 2 5岁。其中不全腭裂 1例 ,单侧完全腭裂 4例 ,双侧完全腭裂 3例。所有患者均伴有重度上颌发育不全畸形 ,7例患者采用改良高位台阶式LeFortⅠ型截骨术 ,1例儿童患者行LeFortⅠ型截骨后采用颅外固定牵引装置完成牵引。手术前术后均投照定位头颅正位、侧位片及曲面体层片、颞颌关节薛氏位片 ,并在模型外科上准确测量牵引距离 ,设计牵引方向 ,牵引完成后即开始术后正畸 4个月后拆除牵引器。结果　 8例患者均按设计要求完成预定牵引。除 1例右侧上颌窦外侧壁截骨线处约有 1cm× 0 .5cm的骨缺损外 ,其余病例牵引区均有致密新骨生成 ,术后咬合关系稳定 ,无感染及其他并发症发生。经平均 2 0个月的术后随访观察 ,上颌骨及咬合关系均稳定 ,无明显复发。 8例患者平均牵引上颌骨向前达 12mm(5～ 15mm) ,患者的上牙槽座角由术前的平均 71°增加到术后的 79° ,所有病例均达到容貌及咬合关系恢复正常。结论　牵引成骨技术是矫治唇腭裂继发重度上颌骨发育不全畸形的有效方法 ,且不需植骨、效果稳定、对腭咽闭合的影响较小 ,值得推广。

Application of distraction osteogenesis in severe maxillary hypoplasia secondary to cleft palate

OBJECTIVE: To evaluate the effect of distraction osteogenesis in correction of severe undeveloped maxilla secondary to cleft palate and to evaluate the selection of distraction modality. METHODS: Distraction osteogenesis was performed upon 8 patients, 6 males and 2 females, aged 11 to 25 years, one with incomplete cleft palate, 4 with unilateral complete left palate, and 3 with bilateral complete cleft palate, all accompanied with severe maxillary hypoplasia. The 7 adult patients were treated by modified high-stepped Le Fort I osteotomy, the other patient, a child, was treated by Le Fort I osteotomy followed by rigid external distraction. X-ray films of skull in lateral, frontal, or panoramic positions, and X-ray film of temporomandibular joint in Schiller's position were taken pre- and postoperatively. In model surgery the accurate distraction distance was measured and the direction of distraction designed. Orthodontic therapy was started immediately after the distraction was completed and the distractor was removed after a period of 4 months' consolidation. RESULTS: The designed distraction was achieved in a11 8 patients. Except in one case with a bone defect 1 cm x 0.5 cm at the osteotomy line in the lateral wall of the right maxillary sinus, dense new bone was formed in the area of distraction in the other cases. The postoperative occlusal relationship was good and stable. No infection and other complication was found. During an average of 20 months' follow-up, the maxilla and occlusion were stable, and no relapse was found. The distance of forward distraction of the maxilla reached an average of l2 mm (5 approximately 15 mm). The SNA angle increased from 71 degree on average preoperatively to an average of 79 degree postoperatively. Both the facial appearance and occlusal relationship returned to normal in a11 the patients. CONCLUSION: Without need of bone grafting and with a stable effect and little influence on platatopharyngeal competence, distraction osteogenesis is an effective method of correcting maxillary hypoplasia secondary to cleft palate and is worthy of spreading.