title: The relationship between temporomandibular joint disk displacement and mandibular asymmetry in skeletal Class III patients.
abstract: OBJECTIVE
  To investigate the relationship between temporomandibular joint disk displacement (TMJ DD) and facial asymmetry in skeletal Class III patients.
  
  
  METHODS
  The subjects comprised 97 skeletal Class III adult patients seeking orthodontic treatment. In addition to the routine lateral and posteroanterior (PA) cephalograms, and regardless of the TMJ status, each subject consented to magnetic resonance imaging (MRI) to evaluate their TMJs. According to MRI readings, subjects were classified into four groups: group 1, bilateral normal disk position; group 2, bilateral DD with or without reduction; group 3, DD more advanced on the right side; and group 4, DD more advanced on the left side. PA and lateral cephalometric variables were analyzed to compare the four groups.
  
  
  RESULTS
  When the TMJ DD was more advanced on one side than on the other, the chin point usually deviated to the advanced side. When the TMJ DD status was equal or bilaterally normal, the amount of mandibular deviation was not significant.
  
  
  CONCLUSIONS
  If a skeletal Class III patient has an asymmetric face, especially in the mandibular region, careful examination is necessary with regard to the status of the TMJ during orthodontic diagnosis and treatment planning.
authors.affiliation: Department of Orthodontics, School of Dentistry & Dental Research Institute, Seoul National University, Seoul, Korea.
authors.forename: Hyung-Joo
authors.initials: HJ
authors.lastname: Choi
authors.forename: Tae-Woo
authors.initials: TW
authors.lastname: Kim
authors.forename: Sug-Joon
authors.initials: SJ
authors.lastname: Ahn
authors.forename: Shin-Jae
authors.initials: SJ
authors.lastname: Lee
authors.forename: Richard E
authors.initials: RE
authors.lastname: Donatelli
mesh_terms: D000293:Adolescent; D000328:Adult; D002508:Cephalometry; D005146:Facial Asymmetry / Q000150:complications*; D005260:Female; D006801:Humans; D004204:Joint Dislocations / Q000209:etiology; D008279:Magnetic Resonance Imaging; D008297:Male; D008313:Malocclusion, Angle Class III / Q000150:complications*; D019224:Temporomandibular Joint Disc / Q000473:pathology; D013705:Temporomandibular Joint Disorders / Q000209:etiology*; D055815:Young Adult