LAUSR

BACKGROUND Some orthodontic patients are associated with temporomandibular joint disorders (TMDs), and the differences between jaw function and psychological states in orthodontic patients with different types of TMDs remains unknown. OBJECTIVE This cross-sectional study aimed to investigate the prevalence of different types of TMDs in orthodontic patients, and to evaluate the relationship between different types of TMDs and jaw functional limitation, psychological distress in orthodontic patients. MATERIALS AND METHODS A questionnaire was sent to patients willing to participate in this survey, which included questions about the demographic characteristics of the participants, the five TMD symptoms (5Ts) of the Diagnostic Criteria for TMDs, the Jaw Functional Limitation Scale-8 (JFLS-8) and the Patient Health Questionnaire for Depression and Anxiety (PHQ-4). The subjects were divided into three groups: painful TMDs (PT), non-painful TMDs (NPT), and TMD-free according to whether they had TMDs and its subtypes. RESULTS A total of 670 valid questionnaires were collected from 182 males and 488 females. The prevalence of TMDs was 35.4%, of which the prevalence of PT was 11.8% and the prevalence of NPT was 23.6%. The median JLFS-8 score of TMD patients was significantly higher than TMD-free, and PT patients were significantly higher than NPT (P=0.026). After adjusting for confounding factors, the jaw function and psychological states and of PT patients and NPT patients were worse than those of the TMD-free group. CONCLUSIONS Among the orthodontic patients surveyed, more than one-third had TMDs, and the prevalence of PT was lower than NPT. Having TMDs is associated with more severe jaw functional limitation, and PT patients were more serious than NPT patients. At the same time, the psychological states of TMDs patients were also worse.