title: Prevalence of temporomandibular disorder subtypes, psychologic distress, and psychosocial dysfunction in Asian patients.
abstract: OBJECTIVE
  To use the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) to investigate the physical diagnoses, psychologic distress, and psychosocial dysfunction in Asian TMD patients. The RDC/TMD Axis I and II findings were compared to those of Swedish and American TMD patients.
  
  
  METHODS
  One hundred ninety-one patients (53 male and 138 female) referred to 2 institutionalized TMD clinics in Singapore were enrolled in the study. The mean age of the predominantly Chinese population (83.2%) was 33.6 +/- 9.3 years. Data from a RDC/TMD history questionnaire and clinical examination were fed directly by patients and clinicians into a computerized diagnostic system (NUS TMDv1.1). Axis I and II findings were generated on-line, based on RDC/TMD rule engines. Data were automatically exported to SPSS for statistical analysis.
  
  
  RESULTS
  Group I (muscle) disorders were found in 31.4% of the patients; Group II (disc displacement) disorders were found in 15.1% and 15.7% of the patients in the left and right temporomandibular joints, respectively; and Group III (arthralgia, arthritis, and arthrosis) disorders were found in 12.6% and 13.0% of the patients in the left and right joints, respectively. Axis II assessment of psychologic status showed that 39.8% of patients experienced moderate to severe depression and 47.6% had moderate to severe nonspecific physical symptom scores. Psychosocial dysfunction was observed in only 4.2% of patients based on graded chronic pain scores.
  
  
  CONCLUSIONS
  Axis I and II findings of Asian TMD patients were generally similar to their Swedish and American cohorts. In all 3 populations, women of child-bearing age represented the majority of patients. Muscle disorders were the most prevalent type of TMD. A substantial portion of TMD patients were depressed and experienced moderate to severe somatization.
authors.affiliation: Department of Restorative Dentistry, Faculty of Dentistry, National University of Singapore, 5 Lower Kent Ridge Road, Singapore 119074, Republic of Singapore. rsdyapuj@nus.edu.sg
authors.forename: Adrian U J
authors.initials: AU
authors.lastname: Yap
authors.forename: Samuel F
authors.initials: SF
authors.lastname: Dworkin
authors.forename: E K
authors.initials: EK
authors.lastname: Chua
authors.forename: Thomas
authors.initials: T
authors.lastname: List
authors.forename: Keson B C
authors.initials: KB
authors.lastname: Tan
authors.forename: H H
authors.initials: HH
authors.lastname: Tan
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D018771:Arthralgia / Q000145:classification; D001168:Arthritis / Q000145:classification; D016009:Chi-Square Distribution; D002681:China / Q000208:ethnology; D003863:Depression / Q000175:diagnosis; D005260:Female; D006801:Humans; D004204:Joint Dislocations / Q000145:classification; D008297:Male; D008410:Masticatory Muscles / Q000503:physiopathology; D001523:Mental Disorders / Q000175:diagnosis*; D008875:Middle Aged; D012737:Sex Factors; D012846:Singapore; D013001:Somatoform Disorders / Q000175:diagnosis; D013315:Stress, Psychological / Q000175:diagnosis*; D019224:Temporomandibular Joint Disc / Q000503:physiopathology; D013705:Temporomandibular Joint Disorders / Q000145:classification* / Q000523:psychology; D013706:Temporomandibular Joint Dysfunction Syndrome / Q000145:classification