分叉下颌神经管的研究概述

The progresses of the bifid mandibular canal

分叉下颌神经管(Bifid Mandibular Canal,BMC)是下颌神经管的一种常见变异,因其主要位于下颌骨升支,磨牙区及磨牙后区,涉及下颌第三阻生齿拔除、种植体植入术、自体骨移植、根管治疗术、下颌升支矢状劈开术等操作时易发生下牙槽神经损伤等并发症。口腔锥形束CT(Cone-Beam Computed Tomography,CBCT)因高分辨率及图像精确能够清晰显影颌骨解剖结构,而通过锥形束CT检测到分叉下颌神经管的发生率约为10.2%-65%^([1-9]),且分叉下颌管之磨牙管在CBCT中的发生率与尸体解剖的发生率基本一致^([10]),因此可见CBCT可以准确的判断分叉下颌管,明确其位置、走向。本文对分叉下颌神经管的发生原因,分型及检测方法进行总结,并对其临床的指导意义进行综述。

A bifid mandibular canal （BMC） is a common variation of the mandibular canal, Because it is mainly located in the mandibular ramus, molar and retromolar regions, procedures such as extraction of an impacted third molar, dental implantation, bone transplantation, root canal treatment and sagittal split ramus osteotomy may cause complication, such as the injury of mandibular nerves. Because of cone-beam computed tomography （CBCT）＇s high-resolution and accurate images, the anatomical structure of mandible can be shown clearly. And the prevalence of BMC according to CBCT is about 10.2%-65%, Moreover, the prevalence of BMC in CBCT is consistent of that in gross anatomical sections. Therefore, CBCT is valuable for evaluating position and direction of the BMC. This paper reviews the causes, classification, detection methods of BMC and the clinical significance.