title: Detectability of anterior displacement of the articular disk in the temporomandibular joint on helical computed tomography: the value of open mouth position.
abstract: OBJECTIVE
  The purpose of this study was to establish the diagnostic reliability of anterior displacement of the articular disk in the temporomandibular joint on helical computed tomography.
  
  
  METHODS
  Ninety-four consecutive patients were examined through use of both computed tomography and magnetic resonance imaging. On axial computed tomography, anterior disk displacement was defined as the presence of an area of soft tissue density that was semilunar in shape and located in front of the mandibular condyle.
  
  
  RESULTS
  With magnetic resonance imaging taken as the diagnostic gold standard in evaluation of articular disk position, the sensitivity, specificity, and accuracy for computed tomography were 91%, 100%, and 97%, respectively, in the closed mouth position and 96%, 99%, and 98%, respectively, in the open mouth position.
  
  
  CONCLUSIONS
  The detectability on axial helical computed tomography of anterior displacement of the articular disk in the temporomandibular joint in the open mouth position was almost equal to that on magnetic resonance imaging. It is recommended that the open mouth position be added when helical computed tomography is used to evaluate patients with temporomandibular joint disease.
authors.affiliation: Department of Oral and Maxillofacial Radiology, School of Dentistry, Niigata University, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Hayashi
authors.forename: J
authors.initials: J
authors.lastname: Ito
authors.forename: J
authors.initials: J
authors.lastname: Koyama
authors.forename: A
authors.initials: A
authors.lastname: Hinoki
authors.forename: F
authors.initials: F
authors.lastname: Kobayashi
authors.forename: Y
authors.initials: Y
authors.lastname: Torikai
authors.forename: Y
authors.initials: Y
authors.lastname: Hiruma
mesh_terms: D015502:Absorptiometry, Photon; D000293:Adolescent; D000328:Adult; D002648:Child; D005260:Female; D006801:Humans; D004204:Joint Dislocations / Q000000981:diagnostic imaging*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009055:Mouth; D011187:Posture; D012015:Reference Standards; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D019224:Temporomandibular Joint Disc / Q000000981:diagnostic imaging* / Q000473:pathology; D013705:Temporomandibular Joint Disorders / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed / Q000379:methods* / Q000592:standards