Cone Beam Computed Tomographic Analysis of the Course and Position of Mandibular Canal

Hooman Khorshidi; Saeed Raoofi; Janan Ghapanchi; Shoaleh Shahidi; Maryam Paknahad

doi:10.1007/s12663-016-0956-9

Cone Beam Computed Tomographic Analysis of the Course and Position of Mandibular Canal

J Maxillofac Oral Surg. 2017 Sep;16(3):306-311. doi: 10.1007/s12663-016-0956-9. Epub 2016 Sep 9.

Authors

Hooman Khorshidi¹, Saeed Raoofi¹, Janan Ghapanchi², Shoaleh Shahidi³, Maryam Paknahad⁴

Affiliations

¹ Department of Periodontics, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
² Department of Oral and Maxillofacial Medicine, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
³ Biomaterial Research Center, Department of Oral and Maxillofacial Radiology, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
⁴ Oral and Dental Disease Research Center, Oral and Maxillofacial Radiology Department, School of Dentistry, Shiraz University of Medical Sciences, Ghasrodasht Street, 7144833586 Shiraz, Iran.

Abstract

Purpose: Estimation of the relative position of infra alveolar nerve (IAN) canal and its relation to the mandibular anatomical landmarks can be clinically useful in minimizing the risk of surgery complications such as neurosensory disturbances that may occur after invasive mandibular surgical procedures. The purpose of the present study was to investigate the anatomic location and radiographic course of the mandibular canal compared to anatomic landmarks on CBCT and to discuss its clinical significance and also to determine the possible correlations between the mandibular position and the age of the patients.

Methods: This cross sectional study was conducted on 242 CBCT of patients (99 males and 143 females). The location of canal was evaluated in 4 different regions. The first section in trans-axial view after mental foramen, in which the loop of mandibular canal is formed, was selected as point 1 for measurement and intervals of 10 mm, respectively, points 2, 3, 4 were selected for measurement. On these sections, the shortest linear distances (mm) from the most buccal and lingual aspects of the canal to the corresponding cortical plates of the mandible and also the minimum linear distance between the inferior aspect of canal and inferior border of mandible in these regions were calculated.

Results: There was statistically significant correlation between the anatomic course of the canal and the patients' gender. The mean vertical position of the canal, as measured from the lower border of the IAN canal to the inferior border of the mandible, was 8.50 mm, ranging from 4.80 to 14.50 mm. On average, the mandibular canal was situated more lingually at all sites to the point it reached the mental foramen. However, at the mental foramen region (Point 1), it was located closer to the buccal cortical plate.

Conclusion: Assessment of the exact course of the IAN preoperatively along the body of the mandible by using CBCT might contribute to efficient and accurate surgical planning and therefore positively influence the surgical results. The results of this study confirm the necessity of using CBCT before invasive surgical procedures to determine the variations in the relative position and course of IAN canal.

Keywords: Cone beam computed tomography; Infra alveolar nerve canal; Mandible; Position.