中文摘要：

目的：利用颅外支架外固定式牵引器治疗唇腭裂继发上颌骨重度发育不足患者,分别采用上颌骨前段截骨和整块截骨方式,探讨不同截骨方式的牵引成骨效果。方法：唇腭裂术后继发上颌骨重度发育不足患者10例,反覆盖均超过10mm。采用传统整块截骨5例,前段分块截骨5例,均利用颅外支架固定式牵引器行术后牵引。通过头影测量分析,比较其矫治效果。利用SPSS13.0软件包对数据进行独立样本t检验。结果：所有患者均成骨良好,无明显并发症,面形及咬合显著改善。牵引成骨后,SNA角、NA与FH夹角、前牙覆盖、零子午线与Sn距离等显著增加。前段截骨组硬腭长度增加7.50mm,2组间有显著差异（P〈0.05）。而软腭长度、静止位腭咽腔深度无显著差异。结论：上颌骨前段截骨牵引在增加硬腭和牙弓长度、避免腭咽腔深度增加及腭咽闭合功能恶化方面具有更大优势,是一种较为理想的矫治唇腭裂术后继发上颌骨发育不足的方法。

英文摘要：

PURPOSE： Conventional maxillary distraction osteogenesis（CMDO） and anterior maxillary segmental distraction（AMSD） were performed in the treatment of severe maxillary hypoplasia secondary to cleft clip and palate（CLP）.The aim of this study was to explore the effectiveness of different osteotomy modalities used in rigid external distraction（RED）.METHODS： Ten patients with severe maxillary hypoplasia secondary to CLP were enrolled in this study.The reverse overjets ranged from 10 to 15 mm with an average of 13.5mm.They were randomly divided into two groups.CMDO was performed in 5 patients and AMSD was used in the other 5 cases.Preoperative and post-treatment lateral cephalograms were compared and cephalometric analysis was performed.The data was analyzed by independent t test with SPSS 13.0 software package.RESULTS： All the patients healed uneventfully and the maxillae moved forward satisfactorily.SNA angles,HA-FH angles,overjets and 0-meridian to Sn distances were increased significantly after distraction osteogenesis.There was significant difference in changes of palatal length between the two groups（P〈0.05）.A mean 7.50 mm palatal length was increased in AMSD group but no obvious changes of palatopharyngeal depth and soft palatal length were found.CONCLUSIONS： With the ability of increasing palatal and arch length,avoiding changes of palatopharyngeal depth,and preserving palatopharyngeal closure function,AMSD shows great value in treatment of maxillary hypoplasia secondary to CLP.It is regarded as a promising and valuable technique in this potentially complicated procedure.