The mandibular interforaminal region has long been considered as the safest area for bone harvesting and implant placement. However, this region includes some important structures such as the lingual foramen and canal. With the increasing use of implants, the number of reported postoperative complications has been rising, therefore, preoperative assessment is a critical component of dental implant surgery to prevent the possibility of neurovascular accidents and complications.
Objectives: This study was undertaken to investigate the frequency and assess the anatomical characteristics of the lingual foramina and their associated bony canals in a group of Egyptian patients using CBCT and to determine the relation of age and gender to these characteristics.
Material and Methods: CBCT scans of 44 Egyptian males and 56 Egyptian females were examined to assess the frequency, distribution, diameter and vertical position of the lingual foramen as well as the course, length, angulation, bifurcation of the canal and the amount of bone buccal to it.
Results: of the 100 examined cases, 44.0% showed 1 lingual foramen, 44.0% showed 2 lingual foramina, 9.0% showed 3 lingual foramina and 3.0% showed 4 lingual foramina. 93.0% were superior and 49.0% were inferior. The mean distance to the alveolar crest was 18.2 ± 4.1 mm and to the menton was 13.1 ± 3.0 mm and the mean canal length was 7.3 ± 2.4 mm. 90% of the canals ran downwards, 5.0% upwards, 5.0% horizontal and in the axial plane 16.0% of the canals ran to the right, 17.0% to the left while 67.0% ran anteriorly and only 21.0% presented bifurcations. The mean vertical angulation was 60.0 ± 20.4 degrees and the mean horizontal angulation was 4.1 ± 6.9 degrees. The mean canal diameter was 0.94 ± 0.27 mm and the mean distance buccal to the foramen was 6.3 ± 1.8 mm. There was a statistically significant negative correlation between age and superior distance and a statistically significant positive correlation between age and inferior distance while no correlation was found between gender and any characteristic.
Conclusions: The lingual foramina and canals present many anatomical characteristics and variations and the CBCT images were able to demonstrate them. The clinical use of CBCT to evaluate each case individually is of utmost importance during preoperative planning to avoid post-operative complications bringing the patients' care to a higher standard of safety and perfection.