title: A comparative study of computed tomography and magnetic resonance imaging for the detection of mandibular canals and cross-sectional areas in diagnosis prior to dental implant treatment.
abstract: BACKGROUND
  Computed tomography (CT) is effective in the diagnosis of dental implants. However, it has the disadvantage of exposing patients to high doses of x-rays, and the mandibular canals cannot be detected by CT in some clinical cases.
  
  
  OBJECTIVE
  The purpose of this study was to examine the detectability of the anatomic morphology of the molar region in the lower jaw (where implantation is common) by CT and magnetic resonance imaging (MRI), to compare the data, and to determine the usefulness of MRI in diagnosis prior to dental implant treatments.
  
  
  METHODS
  Eleven female subjects (average age, 59 years) who had partially edentulous mandibles (total of 19 sites) were included in the study. CT and MRI were performed with the same subjects, and the degrees of identification of the mandibular canal in the first and second molar regions were compared. Dimensional accuracy in the second molar region was also compared.
  
  
  RESULTS
  With CT, the canals of the first molar regions were not identified in 11 of 19 sites; however, MRI identified the canals in all 19 sites. Using the kappa index, we found that the inter- and intraobserver identification reliabilities (0.84 and 0.87, respectively) were excellent, especially for MRI. Dimensional positioning of the canal in the second molar region was almost the same with MRI as with CT.
  
  
  CONCLUSIONS
  MRI is an alternative method in diagnosis prior to dental implant treatment in the mandibular molar region.
authors.affiliation: Department of Oral Rehabilitation, Section of Fixed Prosthodontics, Fukuoka Dental College, Fukuoka, Japan.
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Imamura
authors.forename: Hironobu
authors.initials: H
authors.lastname: Sato
authors.forename: Takashi
authors.initials: T
authors.lastname: Matsuura
authors.forename: Masatsugu
authors.initials: M
authors.lastname: Ishikawa
authors.forename: Ryousuke
authors.initials: R
authors.lastname: Zeze
mesh_terms: D000328:Adult; D000368:Aged; D019412:Anatomy, Cross-Sectional; D005260:Female; D006801:Humans; D007576:Jaw, Edentulous, Partially / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging; D008334:Mandible / Q000098:blood supply / Q000294:innervation*; D008340:Mandibular Nerve / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D008875:Middle Aged; D015588:Observer Variation; D014057:Tomography, X-Ray Computed