Characterization of the Mental Foramen and Mental Loop Measures in Fresh Frozen Cadavers

Normally, the mental foramen is located between the apexes of the roots of the lower premolars, but variations can be found in its shape and position.1 Thus, the anterolateral region must be studied to prevent accidents and complications, such as neurosensory disorders, which may occur during surgery.2–4 Until recently, the area between the mental foramens was considered completely safe for implant placement and the removal of bone grafts. [...]a detailed study of the anterior segment of the mandible demonstrates that, occasionally, an anatomical structure called the anterior loop of the mental nerve may exist in this region.3 The mental nerve loop originates from the mandibular canal and crosses anteriorly to the mental foramen and back toward the foramen itself.4 Several studies have been conducted to detect the prevalence and location of the mental nerve loop as well as to propose safe guidelines for the placement of implants in the interforaminal area.5–7 However, the prevalence of the anterior loop was reported to range from 28%8 to 96%,1 which hinders surgical planning. The size of the loop often varies among individuals, ranging from 0.89 to 7.61 mm.9 Another point to be considered is that the position, width, and length of the mental foramen and mental loop, and how they correlate with the sex of individuals, have not been described in the current literature. [...]the objectives of this study were to evaluate the position of the mental foramen and to verify the presence of and evaluate the mental loop in fresh cadavers. Table 1 Variables of the study* Table 2 Comparison of variables between sexes* Discussion The accurate knowledge of variations in the position and size of the mental foramen and the presence of the mental loop is important for successful surgical procedures on the mandible, such as dental implants, root canal treatments, and orthognathic surgeries.10 In our study, we evaluated the mental foramen location on both sides of the mandible for comparison.