Assessment of Anterior Loop of Inferior Alveolar Nerve: An Anatomical and Radiographic Study

Many surgical procedures including dental implants and osseous genioplasty is performed in the inter foraminal region of mandible and the anterior loop of inferior alveolar nerve is located within the limits of this area. As a result of vast incompatibility between the results of anatomic and radiographic studies regarding the presence and extension of this loop, we decided to perform a study to compare the result of cadaveric dissection and radiographic evaluation of this landmark.

 Anatomic and radiographic analysis were performed on 18 cadaveric hemi mandibles. Presence of mental loop was determined and the extent of anterior loop was measured both in direct anatomical dissection of cadaver hemi mandibles and in CBCT scans.

 14 hemi mandibles (77%) had mental loop both in radiographic and anatomical evaluations. The mean length of mesial extension of mental loop was 2.43mm in cadaveric dissection and 2.37mm in CBCT evaluation. There was excellent reliability between the mean cadaveric measurement and CBCT scan measurement (α coefficient: 0.983).

 In our study a high prevalence of mental loop was showed and despite the diversity in its length, in most cases the length was less than 3 mm. Moreover, CBCT proved to be an accurate and precise modality in detecting and measuring mental loop.