title: Are temporomandibular joint disk displacements without reduction and osteoarthrosis important determinants of mandibular backward positioning and clockwise rotation?
abstract: OBJECTIVE
  The aim of this study was to estimate whether, in patients with temporomandibular joint (TMJ) arthralgia, the magnetic resonanace imaging (MRI) findings of bilateral TMJ disk displacement without reduction (DDwoR) and/or osteoarthrosis (OA) are determinants of mandibular backward positioning and/or clockwise rotation.
  
  
  METHODS
  Bilateral MRI of the TMJ was performed in 50 consecutive TMJ arthralgia patients to identify individuals with bilateral TMJ DDwoR and/or OA. Linear and angular cephalometric measurements were taken to apply selected criteria of mandibular backward positioning (FH to Na-Pog <84°, Na-A-Pog >5°, and SNB <75°) and clockwise rotation (FH to OP >13°, MP to FH >35°, and S-Gn to FH >64°). Logistic regression analysis was used to estimate the association between selected MRI and cephalometric parameters.
  
  
  RESULTS
  In the age- and gender-adjusted analyses, significant increases in risk of mandibular backward positioning and clockwise rotation occurred with bilateral DDwoR and OA (9.5:1; P = .040).
  
  
  CONCLUSIONS
  In patients with TMJ arthralgia the MRI parameters of DDwoR and OA seem to be important determinants of mandibular backward positioning and clockwise rotation.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Center of Dentistry and Oral Surgery, Innsbruck Medical University, Innsbruck, Austria. ruediger.emshoff@uki.at
authors.forename: Rüdiger
authors.initials: R
authors.lastname: Emshoff
authors.forename: Alexander
authors.initials: A
authors.lastname: Moriggl
authors.forename: Ansgar
authors.initials: A
authors.lastname: Rudisch
authors.forename: Klaus
authors.initials: K
authors.lastname: Laimer
authors.forename: Nikolaus
authors.initials: N
authors.lastname: Neunteufel
authors.forename: Adriano
authors.initials: A
authors.lastname: Crismani
mesh_terms: D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D018771:Arthralgia / Q000473:pathology; D002508:Cephalometry; D005260:Female; D006801:Humans; D004204:Joint Dislocations / Q000473:pathology; D016015:Logistic Models; D008279:Magnetic Resonance Imaging; D008297:Male; D008334:Mandible / Q000503:physiopathology*; D008875:Middle Aged; D016017:Odds Ratio; D010003:Osteoarthritis / Q000473:pathology*; D019224:Temporomandibular Joint Disc / Q000473:pathology*; D013705:Temporomandibular Joint Disorders / Q000473:pathology*; D055815:Young Adult