Variations of the bony canal in the mandibular ramus using cone-beam computed tomography

Abstract

The location and configuration of the mandibular canal are important in surgical procedures involving the mandible. Previously, we reported that bifid mandibular canals could be classified into four types: retromolar, dental, forward, and bucco-lingual canals, using cone-beam computed tomography (CBCT). Herein we report three Japanese patients with a bony canal in the mandibular ramus, which was independent of the mandibular canal, using CBCT images. A CBCT unit with a flat panel detector and exposure volume of 102 mm in diameter and 102 mm in height was used. Two-dimensional (2D) and three-dimensional (3D) images in the mandibular ramus region were reconstructed using 3D visualization and measurement software packages. Three bony canals in two patients were considered to correspond to a temporal crest canal, which was raised from the mandibular notch, and reached the antero-inferior region of the coronoid process. One bony canal in one patient, ran bucco-lingually in the mandibular ramus. It is important for variations in the mandibular and bony canals to be carefully observed, by use of CBCT images, in surgical procedures involving the mandible.

Incidence and classification of bifid mandibular canals using cone beam computed tomography

“…Mandibular canal bifurcations were classified into six distinct categories: Classes A, B, C, D, E and F, according to the classification by Naitoh et al 2 ( Table 1), which is based on the pathway of the bifid canal, starting from the mandibular foramen. View of a tomographic and clinical changes of the mandibular canal are illustrated in Figures 2 and 3, respectively.…”

“…Topographically, it is located closer to the inner bone wall up to the mesial aspect of the first molar, moving across to the outer bone wall until it reaches the mental foramen 1 . The radiographic appearance of the mandibular canal is characterized by a radiolucent strip between two radiopaque lines 2 generally as a single structure, presenting different positions inside the body of the mandible in both the upperlower and the medial-lateral directions 3 with occasional duplicate pathways and bifurcations 295 295 295 295 295 nerve in the mandibular canal is of great importance to dentists, especially for those planning orthognathic surgery, mandibular reconstruction, extraction of third molars or installation of osseointegrated implants [6][7] . It is therefore paramount to investigate the frequency and classification of bifid mandibular canals using CBCT to aid surgical planning at posterior regions of the mandible, minimizing the risk of accidents and operative complications.…”

Observation of maxillary incisive canal using dry skulls between Hellman’s dental age IA and IIIC

“…Cone-beam CT was used for the observation of various fine anatomical structures, [7][8][9] and the angulation, and diameter of the maxillary incisive canal in adults were measured using it in previous studies. 4,5) The mean antero-posterior angulation at the inferior level was 75.3 degrees in IIIC, and the value was close to that of adults (mean: 74.3 degrees) in a previous study.…”

“…[7][8][9] In the present investigation, maxillary incisive canals were observed using cone-beam CT and dry skulls in childhood from infancy to school-aged children to clarify their development.…”

Observation of maxillary sinus septa and bony bridges using dry skulls between Hellman's dental age of IA and IIIC

“…The spatial resolution of cone-beam computed tomography (CBCT), which was recently developed, is high in comparison with multislice CT 7) , and maxillary sinus septum presence and fine mandibular anatomical structures were clearly observed using it [8][9][10][11][12] .…”