title: Comparison of three radiographic methods used to locate the mandibular canal in the buccolingual direction before bilateral sagittal split osteotomy.
abstract: OBJECTIVE
  Panoramic radiographs, computerized tomography (CT), and conventional spiral tomographic (Scanora, Soredex, Helsinki, Finland) radiographs were compared for their ability to locate the mandibular canal in the buccolingual direction. Furthermore, the relationship between the cortication of the mandibular canal in panoramic radiographs and the location of the canal in both computerized and conventional tomographic radiographs was assessed.
  
  
  METHODS
  The buccolingual location of the mandibular canal was determined bilaterally in twenty consecutive patients scheduled for bilateral sagittal split osteotomy. The position of the mandibular canal was evaluated by means of panoramic radiography, Scanora, and CT. The three imaging methods were compared for their ability to locate the mandibular canal in the buccolingual direction. The subjective neurosensory deficit of the lower lip and chin on both sides was registered preoperatively and at 4 days, 3 weeks, and 3 months after surgery, and the operative outcome was analyzed in relation to the distance from the mandibular canal to the buccal cortex of the mandible.
  
  
  RESULTS
  CT gave better visualization of the mandibular canal than Scanora imaging. Cortication of the mandibular canal on the panoramic radiograph did not serve as a predictor of the proximity of the mandibular canal to the cortices of the mandible. At 3-month follow-up, there were only eight operated sides with abnormal sensation of the lower lip and chin. In seven of these sides, the distance from the mandibular canal to the buccal cortex was less than 2 mm.
  
  
  CONCLUSIONS
  The buccolingual location of the mandibular canal is visualized better with CT than with Scanora or panoramic radiographs.
authors.affiliation: Institute od Dentistry, University of Oulu, Oral and Maxillofacial Department, Oulu University Hospital, Finland. leena.ylikontiola@oulu.fi
authors.forename: Leena
authors.initials: L
authors.lastname: Ylikontiola
authors.forename: Katariina
authors.initials: K
authors.lastname: Moberg
authors.forename: Sisko
authors.initials: S
authors.lastname: Huumonen
authors.forename: Kari
authors.initials: K
authors.lastname: Soikkonen
authors.forename: Kyösti
authors.initials: K
authors.lastname: Oikarinen
mesh_terms: D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D016009:Chi-Square Distribution; D005260:Female; D006801:Humans; D008297:Male; D008334:Mandible / Q000000981:diagnostic imaging* / Q000601:surgery; D008340:Mandibular Nerve / Q000000981:diagnostic imaging*; D008875:Middle Aged; D019647:Oral Surgical Procedures / Q000009:adverse effects; D010027:Osteotomy / Q000009:adverse effects / Q000379:methods; D010292:Paresthesia / Q000209:etiology; D019252:Radiography, Dental, Digital; D011862:Radiography, Panoramic; D014057:Tomography, X-Ray Computed