Lee Han Eol, Han Se Jin
Department of Oral and Maxillofacial Surgery, College of Dentistry, Dankook University, Cheonan, Korea.
J Korean Assoc Oral Maxillofac Surg. 2018 Aug;44(4):167-173. doi: 10.5125/jkaoms.2018.44.4.167. Epub 2018 Aug 29.
Classification of the degree of postoperative nerve damage according to contact with the mandibular canal and buccal cortical bone has been studied, but there is a lack of research on the difference in postoperative courses according to contact with buccal cortical bone. In this study, we divided patients into groups according to contact between the mandibular canal and the buccal cortical bone, and we compared the position of the mandibular canal in the second and first molar areas.
Class III patients who visited the Dankook University Dental Hospital were included in this study. The following measurements were made at the second and first molar positions: (1) length between the outer margin of the mandibular canal and the buccal cortical margin (a); (2) mandibular thickness at the same level (b); (3) Buccolingual ratio=(a)/(b)×100; and (4) length between the inferior margin of the mandibular canal and the inferior cortical margin.
The distances from the canal to the buccal bone and from the canal to the inferior bone and mandibular thickness were significantly larger in Group II than in Group I. The buccolingual ratio of the canal was larger in Group II in the second molar region.
If mandibular canal is in contact with the buccal cortical bone, the canal will run closer to the buccal bone and the inferior border of the mandible in the second and first molar regions.
根据与下颌管和颊侧皮质骨的接触情况对术后神经损伤程度进行分类的研究已有报道，但对于根据与颊侧皮质骨的接触情况术后病程差异的研究尚少。在本研究中，我们根据下颌管与颊侧皮质骨的接触情况将患者分组，并比较了第二磨牙和第一磨牙区域下颌管的位置。
本研究纳入了就诊于韩国檀国大学牙科学院的Ⅲ类患者。在第二磨牙和第一磨牙位置进行以下测量：（1）下颌管外缘与颊侧皮质骨边缘之间的长度（a）；（2）同一水平的下颌骨厚度（b）；（3）颊舌比=（a）/（b）×100；（4）下颌管下缘与下颌骨下缘之间的长度。
Ⅱ组中，从下颌管到颊侧骨、从下颌管到下颌骨下缘的距离以及下颌骨厚度均显著大于Ⅰ组。在第二磨牙区域，Ⅱ组下颌管的颊舌比更大。
如果下颌管与颊侧皮质骨接触，在第二磨牙和第一磨牙区域，下颌管将更靠近颊侧骨和下颌骨下缘走行。
