下颌正中管的锥形束CT三维重建

摘要

目的 通过锥形束CT(CBCT)扫描对下颌正中管的存在与否、走向及其与周围组织的三维关系进行评估及测量,为颏下区手术的安全提供保障.方法 对100例患者的CBCT图像进行三维重建并测量.测量项目包括Mandibular Icisive Canal(MIC)的存在与否,MIC垂直向和水平向直径,MIC在下颌管起始点,第一前磨牙对应点,尖牙对应点,切牙对应点至牙根尖、下颌骨颊侧壁、舌侧壁、下颌下缘以及牙槽嵴顶的垂直距离.结果 100例CBCT中百分百可见MIC.MIC与颊侧骨板和舌侧骨板平均距离分别为3.52±0.54 mm和5.37±0.25 mm,与下颌骨下缘、牙根尖和牙槽嵴顶的平均距离为10.44±0.61、10.57±0.76及20.21±0.83 mm.MIC到下颌骨下缘的距离男性为10.70±0.43 mm,女性为10.17±0.63 mm,P<0.05,差异具有统计学意义.结论 MIC在CBCT中检出率高且走向各异.%Objective To find out the existence of Mandibular Incisive Canal (MIC) through CBCT scanning and measure its 3D relationship with the surrounding tissue, so as to provide protection for the operation in submental area. Methods CBCT images of 100 patients were measured and three dimensionally reconstructed. The measurement in-clude following items, the existence of the MIC; vertical and horizontal diameter of MIC; vertical distance from MIC to the mandibular buccal and lingual wall;to the root apex, to the inferior border of mandible and alveolar crest in corre-sponding points (the mandibular first premolar, canine and incisor). Results the MIC was 100%visible in CBCT. The mean distance between MIC and buccal bone plate and lingual bone plate was 3.52 ± 0.54 mm and 5.37 ± 0.25 mm. The average distance from the inferior border of the mandible, the apex of the root and the crest of the alveolar bone was 10.44 ± 0.61 mm、10.57 ± 0.76 mm and 20.21 ± 0.83 mm relatively. The distance from MIC to the inferior border of the mandible in male was 10.70 ± 0.43 mm and 10.17 ± 0.63 mm in female, P<0.05. Conclusion The detection rate of MIC is high and there are many variations. It was suggested that the location and size of the MIC should be checked in CBCT in each patient before operation, which is helpful to avoid surgical complications in submental area.