Anterior loop of the mental canal: an anatomical-radiologic study.

This study sought to characterize the anatomical dimensions of the anterior mental loop and to determine the accuracy of conventional radiographs in identifying its presence and dimensions. The study group consisted of 46 hemimandibles fixed in formalin. Radiographs of the area between the mental foramen and the midline were obtained and evaluated for each hemimandible, followed by dissection and physical examination of the same area. Anatomically, an anterior loop of the mental nerve was observed in only 13 hemimandibles (28%). The anterior extension of the loop ranged from 0.4 to 2.19 mm. No correlation was found between the radiographic image and the anatomical shape of the loop. Of the radiographically diagnosed loops, 40% were not seen in anatomical examination. In cases with a false radiologic loop, a correlation was found between the diameter of the origin of the incisive canal and the radiologic interpretation of the loop. The radiologic appearance or diagnosis of the anterior mental loop in cadaver mandibles does not disclose the true ramification of the inferior alveolar nerve to the mental and incisive nerve.