title: Characterization of patients with disc displacement without reduction unresponsive to nonsurgical treatment: a preliminary study.
abstract: OBJECTIVE
  Arthrocentesis and arthroscopic lysis and lavage have been described as effective treatment modalities for temporomandibular joint (TMJ) disc displacement without reduction (DDw/oR). More commonly, nonsurgical intervention is offered as the desired first-line treatment; however, a certain group of DDw/oR patients receiving nonsurgical treatment may remain unresponsive, thereby prolonging suffering and treatment dissatisfaction. The purpose of this study is to characterize these nonresponders by evaluating the characteristic pretreatment findings peculiar to this group.
  
  
  METHODS
  This retrospective study was based on the review of pretreatment clinical and magnetic resonance imaging (MRI) findings of 52 DDw/oR patients who were treated with stabilization appliance, jaw-stretching exercise, and nonsteroidal anti-inflammatory medication. On the last treatment visit, each patient was classified as either a responder (R) or nonresponder (NR) based on the satisfaction or dissatisfaction with the treatment received, respectively. Pretreatment data were then examined and analyzed by logistic regression to identify which clinical and MRI findings were specifically related to the NR group.
  
  
  RESULTS
  Logistic regressions indicated that NR had significantly higher odds ratio for pretreatment pain-free mouth opening of less than 30 mm (odds ratio [OR] = 7.385), "stuck" disc (OR = 4.521), and unchanged disc shape during mouth opening (OR = 4.050). Multiple logistic regression analyses revealed that these factors combined gave the highest likelihood ratio of 15.90 ( P = .001), indicating a strong possibility that these factors are associated with the NR group.
  
  
  CONCLUSIONS
  Nonresponders can be characterized by their pretreatment pain-free mouth opening (<30 mm) in combination with MRI confirmation of "stuck" disc and unchanged disc shapes during mouth opening.
authors.affiliation: UCLA School of Dentistry, 10833 LeConte Avenue, 63-078 CHS, Los Angeles, CA 90095-1668, USA. iwase@ucla.edu
authors.forename: Hirotate
authors.initials: H
authors.lastname: Iwase
authors.forename: Tadaaki
authors.initials: T
authors.lastname: Sasaki
authors.forename: Setsuko
authors.initials: S
authors.lastname: Asakura
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Asano
authors.forename: Somsak
authors.initials: S
authors.lastname: Mitrirattanakul
authors.forename: Yoshizo
authors.initials: Y
authors.lastname: Matsuka
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Imai
mesh_terms: D000328:Adult; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000627:therapeutic use; D002012:Bruxism / Q000503:physiopathology; D005157:Facial Pain / Q000503:physiopathology; D005260:Female; D006801:Humans; D004204:Joint Dislocations / Q000503:physiopathology / Q000628:therapy*; D008279:Magnetic Resonance Imaging; D008297:Male; D020247:Myofunctional Therapy; D017090:Occlusal Splints; D017060:Patient Satisfaction; D016059:Range of Motion, Articular / Q000502:physiology; D012189:Retrospective Studies; D012307:Risk Factors; D019224:Temporomandibular Joint Disc / Q000473:pathology*; D013705:Temporomandibular Joint Disorders / Q000503:physiopathology / Q000628:therapy*; D014056:Tomography, X-Ray; D016896:Treatment Outcome; D014313:Trismus / Q000503:physiopathology
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal