Abstract:

Objective    To observe and measure the mandibular alveolar bone morphology at the area of mental foramen in the patients with mandibular deviation by CBCT to provide reference for genioplasty in orthognathic surgery，so as to reduce the complications such as the injury to nerves and blood vessels. Methods    In this study，84 adults with mandible deviation were selected，CBCT scans were conducted and InVivo 5 software was used to reconstruct the mandible；locate the markers；observe and measure and analyze the position of the mental foramen and the morphology of the mental canal. All the measurements were analyzed with SSPS 17.0 package. Results    The mental foramen was mostly below the second premolar at the mandibular（39.29%），and below the first premolar is the least（11.90%）. There was no significant difference between the oblique side and the contralateral side on all measurement values，in addition to the angle of the mental canal，the gender difference is significant，and it's much greater in males. Conclusion    There are some differences in the position of the mental foramen between the individuals of mandibular deviation deformity and the normal，and also are somewhat different between males and females. The CBCT imaging can clearly display the three-dimensional structure，the trend and the relationship with adjacent structures of the mental canal，which can effectively reduce or avoid the surgical complications.

Key words: mandibular deviation；mental foramen；mental canal；genioplasty；cone-beam computed tomography, CBCT

摘要：

目的    应用锥形束CT（CBCT）观察、测量下颌骨偏斜畸形患者颏孔区牙槽骨形态，为正颌外科手术中颏成形术提供参考，减少神经、血管损伤等并发症的发生。方法    选取2014年3月至2015年10月大连市口腔医院收治的下颌骨偏斜畸形成人患者84例，进行CBCT扫描，用InVivo5软件对下颌骨进行三维重建，定位标记点，观察、测量和分析下颌骨颏孔位置及颏管形态，用SPSS17.0软件包对测量结果进行分析。结果    颏孔大部分位于下颌第二前磨牙下方（39.29%），位于第一前磨牙下方（11.90%）者最少。各测量值在偏斜侧和偏斜对侧的差异无统计学意义，除颏管角度外，性别差异较显著，均为男性大于女性。结论    下颌骨偏斜畸形患者颏孔位置较正常人有一定差异，男女性之间也有所不同，CBCT影像可清晰显示颏管的三维结构、走向以及与邻近结构的关系，可以有效减少或避免手术并发症。

关键词: 下颌骨偏斜, 颏孔, 颏管, 颏成形术, 锥体束CT（CBCT）