Compression of the Inferior Alveolar Canal by Mandibular Third Molar among Images Taken from Patients Visiting Dental Imaging Centres of Kathmandu: A Descriptive Cross-sectional Study

Abstract

Introduction: Third molars are common teeth to be impacted. The position of mandibular third molar is such that it is in close contact with inferior alveolar canal which may lead to nerve damage during its removal. So, this study was conducted to find out the prevalence of compression of inferior alveolar canal by mandibular third molars. Methods: This descriptive cross-sectional study was conducted on images collected from Dental Imaging Centers of Nepal from 25th June 2020 to 15th February 2021 after obtaining ethical clearance from Nepal Health Research Council (Reference number: 2100). A convenience sampling method was used to collect 433 cone-beam computed tomography images showing the relation between the third molars and inferior alveolar canal. Data were analyzed using the Statistical Package for the Social Sciences version 16. Point estimate at 95% confidence interval was calculated along with frequency and proportion for the binary data. Results: Out of 433 images, 135 (31.17%) (26.80-35.53 at 95% Confidence Interval) images showed compression of inferior alveolar nerve by mandibular third molar. The study result indicated that 16 (11.85%) buccally placed, 50 (37.03%) lingually placed and 69 (51.11%) inferiorly placed inferior alveolar canal were compressed by apices of mandibular third molars. Conclusions: The prevalence of compression of inferior alveolar canal by mandibular third molar was found to be similar to other studies done in similar settings. Compression of the canal was more evident when inferior alveolar canal is situated lingually.

Keywords

• cone beam computed tomography; inferior alveolar nerve; mandible; third molar.