Department of Oral Radiology, Tsurumi University School of Dental Medicine, Tsurumi-ku, Yokohama, Japan.
Dentomaxillofac Radiol. 2012 Sep;41(6):460-5. doi: 10.1259/dmfr/60245722. Epub 2011 Nov 24.
The aims of this study were (1) to assess the validity of limited cone beam CT (CBCT) in detecting the distribution of bifid mandibular canals in the retromolar region by comparing its findings with those of panoramic radiography and spiral CT imaging, and (2) to confirm the contents of such canals depicted on limited CBCT images by using gross anatomical and histological methods.
Bilateral bifid mandibular canals of a Japanese cadaver were investigated. The canals depicted on panoramic radiography, spiral CT and limited CBCT images were compared. Cross-sectional limited CBCT images of these canals were compared with gross anatomical sections of the mandible and their contents were confirmed histologically.
The spiral CT and limited CBCT images showed the bilateral bifid mandibular canals in the retromolar region whereas the panoramic radiographs indicated the presence of only the left bifid mandibular canal. The canal distribution was more distinct in the limited CBCT images than in the spiral CT images and the cross-sectional limited CBCT images were consistent with the gross anatomical sections. Histologically, the canals contained several nerve bundles and arteries among which the largest nerve and artery were of a similar size.
Limited CBCT is valuable for assessing the distribution of bifid mandibular canals. It is clinically significant to accurately localize a bifid mandibular canal of the retromolar region because it contains a nerve bundle and artery.
本研究的目的是（1）通过与全景片和螺旋 CT 成像比较，评估有限锥形束 CT（CBCT）检测磨牙后区双下颌管分布的准确性，（2）通过大体解剖和组织学方法证实有限 CBCT 图像中显示的此类管腔的内容物。
对一名日本尸体的双侧分叉下颌管进行了研究。比较了全景片、螺旋 CT 和有限 CBCT 图像上显示的管腔。将这些管腔的有限 CBCT 图像的横截面与下颌骨的大体解剖部分进行比较，并通过组织学方法证实其内容物。
螺旋 CT 和有限 CBCT 图像显示双侧分叉下颌管位于磨牙后区，而全景片仅显示左侧分叉下颌管。有限 CBCT 图像上的管腔分布比螺旋 CT 图像更明显，有限 CBCT 图像的横截面与大体解剖部分一致。组织学上，管腔中包含几个神经束和动脉，其中最大的神经和动脉大小相似。
有限 CBCT 可用于评估分叉下颌管的分布。准确定位磨牙后区的分叉下颌管具有临床意义，因为它包含一个神经束和动脉。
