title: Evaluation of temporomandibular disorders in Class III patients treated with mandibular cervical headgear and fixed appliances.
abstract: BACKGROUND
  Our aim in this study was to evaluate the prevalence of temporomandibular disorders (TMD) in Class III patients treated with mandibular cervical headgear (MCH) and fixed appliances.
  
  
  METHODS
  The sample of 75 patients included 25 patients with no previous orthodontic treatment, 25 Class I patients who had undergone orthodontic treatment with fixed appliances and without extractions, and 25 patients with dentoskeletal Class III disharmonies treated with MCH and fixed appliances. The Helkimo index was used to test the prevalence of TMD symptoms in the 3 groups. The prevalence rates of the Helkimo index in the 3 groups were compared with the z score on proportions.
  
  
  RESULTS
  No statistically significant differences in the prevalence rates of the Helkimo index scores in the 3 groups were found (P = .367). Most subjects in the 3 groups had an Helkimo index of zero (66.7%).
  
  
  CONCLUSIONS
  Subjects with Class III malocclusions treated with MCH and fixed appliances do not have greater prevalence of TMD symptoms than do Class I subjects treated with fixed appliances or untreated subjects.
authors.affiliation: Department of Orthodontics, CES University, Medellin, Colombia.
authors.forename: Diego
authors.initials: D
authors.lastname: Rey
authors.forename: Giovanni
authors.initials: G
authors.lastname: Oberti
authors.forename: Tiziano
authors.initials: T
authors.lastname: Baccetti
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D005115:Extraoral Traction Appliances / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008297:Male; D008311:Malocclusion, Angle Class I / Q000628:therapy; D008313:Malocclusion, Angle Class III / Q000628:therapy*; D009967:Orthodontic Appliances / Q000009:adverse effects; D009971:Orthodontics, Corrective / Q000009:adverse effects / Q000295:instrumentation*; D012189:Retrospective Studies; D017678:Sex Distribution; D013705:Temporomandibular Joint Disorders / Q000175:diagnosis / Q000209:etiology*