The Dimensions of the Mandibular Incisive Canal and Its Spatial Relationship to Various Anatomical Landmarks of the Mandible: A Study Using Cone Beam Computed Tomography

Purpose: Often during implant surgery in the mandibular symphysis area, little attention is given to the mandibular incisive canal. Although it is true that intraoperative and postoperative complications with implants in the incisive mandibular canal are rare, they are more common when harvesting bone from the chin area. Loss of tooth sensation is a rather frequent consequence. The present study used cone beam computed tomography (CBCT) to identify and measure variations in the dimensions of the incisive canal and its spatial relationship to various anatomical landmarks of the mandible to reduce the number of postoperative complications after selective procedures in the symphysis area. Materials and Methods: One hundred two patients scanned for a variety of clinical indications were included in this retrospective study. The dimensions of the incisive mandibular canal were assessed, and the distances from the various mandibular landmarks were measured using the multiplanar capabilities of the CBCT device's software. Results: The results show that a mandibular incisive canal was identified by CBCT in 93% of the cases and had a mean length of 8.9 mm (range, 0 to 24.6 mm). The mean distances of the canal from the root tips of the premolars, canines, and incisors were 6.9 mm, 7.3 mm, and 10.4 mm, respectively. The mean distances from the canal to the buccal cortical border in the same tooth positions were 2.8 mm, 4.4 mm, and 4.8 mm, respectively. Conclusions: In a large majority of the sample, a mandibular incisive canal was identified by CBCT. The large variation in the spatial relationships of the canal mandates a case-by-case preoperative radiographic evaluation of the canal, and CBCT seems able to fulfill the task. Keywords: cone beam computed tomography, dental implants, incisive canal, incisive nerve