Localization of mandibular foramen – a comparison between dry bones and orthopantomogram

An inferior alveolar nerve block is a usual practice by a dental practitioner. Panoramic radiography is a widely used technique in dentistry to get a clear and comprehensive view before planning any treatment. The study aimed to compare the morphometric localization of mandibular foramen (MF) on dry bones and orthopantomogram. The study was designed in two phases: a morphometric study on dry human mandibles (phase I) and orthopantomograms of the same dry human mandibles (phase II). The study materials were 200 dry north Indian human mandibles belonging to unknown sex obtained from the Department of Anatomy. Descriptive statistics, including range, mean±standard deviation, paired t-test to compare dry bones and orthopantomogram, Pearson's correlation coefficient, and measurement error, were used. T-test was applied separately to compare the right and left sides of dry bones. The distance of mandibular foramen from the posterior border and lower border is shorter on the right side than on the left. Its distance from the anterior border and the mandibular notch was greater on the right side. On panoramic radiographs, the distance of MF from nearby anatomical landmarks on the mandible was highly unreliable except for the mandibular notch. Our findings demonstrate a statistically significant difference between distances on dry bone and OPG but no statistically significant difference between MF-notch on both sides and MF-AB on the right side. As a result, a surgeon can rely upon a mandibular notch to locate mandibular foramen during clinical procedures. Magnification is an inbuilt property of OPG; for precise localization of MF, it is advisable to proceed with advanced three-dimensional techniques to protect viable anatomical structures.