Visibility of mandibular anatomical landmarks in panoramic radiography: A retrospective study

Aims: To determine the frequency, visibility and gender variations of mental foramen (foramen mentale), incisive canal, anterior loop of mental nerve, and mandibular canal (canal mandibulaire) in different age groups. Materials and Methods: The study was done in 179 orthopantomograms (OPG) which were taken using Digital Orthophos XG machine. The anatomical landmarks such as mandibular canal, mental foramen, anterior loop of mental nerve, and incisive canal were analyzed in the radiographs and scores were recorded. Results: According to a sample size of 179, the mandibular canal was visible in 98%. In 16% of the cases, with 14% poor perceptibility anterior looping of the mental nerve was visible. The mental foramen showed good visibility in 51%. In 23% of the cases, the incisive canal was observed. Chi-square test was done which showed the statistical difference with a P < 0.05 existed between appearance of mandibular canal and age and difference in P values in males and females in their visibility based on the sample size. Conclusion: Panoramic radiographs provided sufficient information for mental foramen and mandibular canal. But for better visualization, detection of structures in between for aminal region and for performing surgery for implant placement in this region it may require to be replaced with three-dimensional imaging like cone-beam computed tomography.