Topography of the lingual foramen using micro-CT

Abstract

The aim of this study was to verify the location and size of the lingual foramina and the course of their canals using micro-computed tomography (micro-CT).Twenty mandibles from Korean were scanned using a micro-CT system and reconstructed three dimensionally to detect the lingual foramina and their canals. Four mandibles (20%) had a single foramen at the lingual side of the mandibular midline, eight mandibles (40%) had two foramina, and five mandibles (25%) had three foramina. Three mandibles (15%) had four small foramina with short canals. The foramina were classified as either superior lingual foramina (SLFs) or inferior lingual foramina (ILFs) according to their relative location to the mental spine. The diameters of SLFs and ILFs were 0.75±0.36 and 0.73±0.38mm (mean±SD), respectively. The distances from the inferior border of the mandible to SLFs and ILFs were 12.58±2.49 and 6.43±3.08mm, respectively. Ten canals (21%) traveled upward to the labial side, 24 canals (51%) downward and 13 canals (28%) parallel to it. Ten mandibles (50%) had lateral foramina.With regard to implant surgery of the anterior mandibular region, the most hazardous zones for lingual foramina are 0–2mm from the midline, 3–17mm from the inferior border of the mandible, and the anterior 0–7mm from the lingual side. Careful preoperative planning taking into account the anatomical location of these foramina might help to avoid complications due to damage to the foramina, their canals, and their contents.