title: Observation of bifid mandibular canal using cone-beam computerized tomography.
abstract: OBJECTIVE
  Some variations of the mandibular canal (so-called bifid mandibular canal) have been reported using various radiography techniques; however, the occurrences of bifid mandibular canal were less than 1% according to panoramic radiographic surveys. The purpose of the present investigation was to clarify the rate and type of bifid mandibular canal in the mandibular ramus region, as observed using cone-beam computerized tomography (CBCT) images.
  
  
  METHODS
  One hundred twenty-two patients who had undergone preoperative imaging of dental implant treatment using CBCT were enrolled in the investigation. Two-dimensional (2D) images of various planes in the mandibular ramus region were reconstructed on a computer using three-dimensional visualization and measurement software. The course of the mandibular canal was observed and the length of the bifid canal was measured.
  
  
  RESULTS
  Bifid mandibular canal in the mandibular ramus region was observed in 65% of patients and 43% of sides. Bifid mandibular canal can be classified into four types: retromolar, dental, forward, and buccolingual canals.
  
  
  CONCLUSIONS
  Bifid mandibular canal was observed at a high rate using CBCT.
authors.affiliation: Department of Oral and Maxillofacial Radiology, School of Dentistry, Aichi-Gakuin University, 2-11, Suemori-Dori, Chikusa-Ku, Nagoya 464-8651, Japan. mune@dpc.aichi-gakuin.ac.jp
authors.forename: Munetaka
authors.initials: M
authors.lastname: Naitoh
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Hiraiwa
authors.forename: Hidetoshi
authors.initials: H
authors.lastname: Aimiya
authors.forename: Eiichiro
authors.initials: E
authors.lastname: Ariji