RESUMEN
OBJECTIVES: This study proposed a conceptual framework for reporting Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) Axis I conditions and investigated the prevalence of TMD subtypes/categories in patients from Confucian heritage cultures. Variances in gender, age, and TMD chronicity between Chinese (CN) and Korean (KR) patients were also explored. MATERIALS AND METHODS: Subjects were recruited from consecutive patients seeking care at two University-based centers in Beijing and Seoul. Eligible patients completed a demographic survey as well as the DC/TMD Symptom Questionnaire and were clinically examined according to the DC/TMD methodology. Axis I diagnoses were subsequently rendered with the DC/TMD algorithms and documented using the stratified reporting framework. Statistical evaluations were performed with chi-square, Mann-Whitney U tests, and logistic regression analysis (α = 0.05). RESULTS: Data of 2008 TMD patients (mean age 34.8 ± 16.2 years) were appraised. Substantial differences in female-to-male ratio (CN > KR), age (KR > CN), and TMD duration (KR > CN) were observed. Ranked frequencies of the most common Axis I diagnoses were: CN - disc displacements (69.7%) > arthralgia (39.9%) > degenerative joint disease (36.7%); KR - disc displacements (81.0%) > myalgia (60.2%) > arthralgia (56.1%). Concerning TMD categories, notable differences in the prevalence of intra-articular (CN 55.1% > KR 15.4%) and combined (KR 71.8% > CN 33.4%) TMDs were discerned. CONCLUSIONS: Though culturally similar, the two countries require disparate TMD care planning/prioritization. While TMJ disorders in children/adolescents and young adults should be emphasized in China, the focus in Korea would be on TMD pain in young and middle-aged adults. CLINICAL RELEVANCE: Besides culture, other variables including socioeconomic, environmental, and psychosocial factors can influence the clinical presentation of TMDs. Chinese and Korean TMD patients exhibited significantly more intra-articular and combined TMDs respectively.