Investigation of morphometric changes in the mandibular canal and mental foramen with cone beam computed tomography and panoramic radiography

Aim: Determining the anatomical localization and variations of the mandibular canal (MC) is very important for surgical procedures such as implant operations in the mandible, extraction of impacted 3rd molars, sagittal split ramus osteotomy. The aim of our study is to evaluate the variations of the mandibular canal and mental foramen, the relationship between the mandibular canal and impacted wisdom teeth, and the vertical course of the mandibular canal using panoramic radiography and cone beam computed tomography (CBCT) in Turkish society. Material and Method: In our study, all patients who applied to Süleyman Demirel University, Faculty of Dentistry, Oral and Maxillofacial Radiology Clinic for various reasons between 2019 and 2023 and who had panoramic radiography and CBCT imaging were retrospectively examined. The frequency of bifid/trifid mandibular canal, the presence of accessory mental foramen and anterior loop, and the relationship between impacted wisdom teeth and mandibular canal were evaluated in panoramic radiography and reconstructed CBCT images included in the study. The obtained data were compared according to gender, side and age groups. Results: Of the 184 patients included in the study, 97 were female (52.72%) and 87 were male (47.28%). Bifid/trifid mandibular canal was detected in 38 (12.66%) of the examined CBCT sections. The location of the mental foramen was detected between the mandibular premolars in both imaging methods. The presence of anterior loop was detected in 24.7% of CBCT images and 17.3% of panoramic radiography, and the rate of mandibular incisive canal was detected as 31.7% and 9.3%, respectively. Conclusion: The recognition of variations in the mandibular canal and mental foramen by dentists can prevent complications during and after oral surgery applications and can change the course of the preoperative surgical planning. For this purpose, panoramic radiography increases its acceptability as a first-line radiodiagnostic imaging technique, as it allows the jaws and anatomical structures to be examined together and gives an idea about the vertical distance and mesiodistal relationship. However, when the existence of various variations is suspected and 3D examination of the jaws and related anatomical structures is required, it has been concluded that CBCT is an effective method. Keywords: Cone beam computed tomography, Panoramic radiography, Mandibular canal variations, Accessory mental foramen