下颌骨发育性不对称畸形颌面硬组织特征的研究

The structural characters of craniofacial skeleton in patients with mandibular developmental asymmetry

目的:通过对44例下颌骨发育性不对称畸形患者的X线头颅定位后前位片的定点测量与分析,研究下颌骨不对称畸形患者颌面骨组织的特征性变化。方法:应用自行设计的正颌外科电脑模拟手术系统软件,选择41个头颅标志点,对44例下颌骨发育性不对称畸形患者的头颅定位后前位片进行测量分析。测量内容包括各标志点到面中线之间的距离、面部高度及颅面角度。采用加藤信一提出的非对称率计算方法[Q=(G-K)/G×100%]计算颌面骨各点、距离及角度的非对称率。采用SPSS11.0统计软件包对所得数据进行团体t检验。结果:下颌骨发育性不对称畸形患者的颅面骨非对称率自颅面上、中、下1/3逐次递增。面上1/3中的颧额缝点的非对称率在正常范围,而眶内侧点则与正常值有显著差异。颅面部非对称率较大的部位在下颌角点、角前切迹点、磨牙点、鼻旁点以及上颌牙槽突点等。上颌骨的不对称表现在牙槽骨的高度与宽度不对称。结论:下颌骨不对称畸形可引起上颌骨的继发性畸形改变,即上颌骨尤其是牙槽骨具有一定程度的功能代偿性变化。提示对于发育性偏颌畸形患者,早期功能性矫治具有重要意义。

PURPOSE： To study the structural characters of cranio-facial skeleton of the patients with mandibular developmental asymmetry. METHODS： Cephalometric analysis was undertaken with the P-A cephalometric radiograph in 44 cases of mandibular developmental asymmetry. 41 cephalometric landmarks, horizontal and vertical distance on different landmarks, and 6 angles were measured and their asymmetric ratios were calculated by the formular Q=（G-K）/G× 100%. Data were analyzed with SPSS 11.0 software package for group t test. RESULTS： The most asymmetric points were on the Go, Ag, M and Pa. The lower face had more asymmetry than the upper face. The asymmetry of the maxilla was mainly located in the alveolus region. CONCLUSIONS： The results suggest that the maxillary alveolar bone had compensatory alteration in mandibular asymmetry cases. Early functional treatment for the mandibular developmental asymmetry is of great importance.