Purpose: Bruxism is commonly considered a major risk factor for temporomandibular disorders (TMD), and the psychosocial factors had been one of the etiologic factor of bruxism. But there are still unsolved issues on the relationship between sleep bruxism and TMD and the etiologic factors of bruxism. This study is aim to evaluate the clinical and psychosocial characteristics according to diagnostic grade of bruxism in TMD patients. Methods:Three hundred subjects were enrolled who were under the stabilization splint therapy for TMD. Recently international consensus proposed a diagnostic grading system of "possible", "probable", and "definite" sleep or awake bruxism for clinical and research purpose. According to their suggestion, we classified these subjects as self-reported bruxism (SRB) and wear facet bruxism (WFB). We investigated the clinical characteristics (sex, age, chief complaint, pain duration, visual analogue scale), sum of tenderness (temporomandibular joint, masticatory muscles, cervical muscles), diagnosis of TMD according to research diagnostic criteria (the Research Diagnostic Criteria for Temporomandibular Disorders, RDC/TMD), headache, subjective sleep quality (Pittsburgh Sleep Quality Index, PSQI), and psychosocial characteristics (Symptom Checklist-90-Revised, SCL-90-R) in enrolled subjects. We compared the clinical and psychosocial characteristics between these bruxism groups.Results: There were no significant correlation between self-reported and WFB (p=0.13). SRB subjects more reported pain as a chief complain than subject who did not report bruxism (p=0.014). The mean score of global PSQI was significantly higher in SRB than in did not report positively subjects (p=0.045). The mean score of anxiety and phobic anxiety was significantly higher in SRB than in did not reported positively subjects (p=0.045, p=0.041). Conclusions:Although bruxism is regarded as risk factor of TMD, this study showed inconsistent result between SRB and clinically detected bruxism by wear facet on slpint. We suggest that the clinician should consider with extreme caution when they assess SRB.

Clinicians are familiar with limitation of opening mouth caused by temporomandibular disorders. Sometimes, patients also complain of difficulty in closing mouth. Difficulty in closing mouth can be caused by anterior, posterior disc displacement, and subluxation of temporomandibular joint (TMJ). In this report, we presented a patient who had a difficulty in both opening and closing mouth. The patient complained of TMJ noises and intermittent limitation of opening mouth, and inability to get teeth back into maximal intercuspal position. Magnetic resonance images revealed that the left TMJ had an anterior disc displacement with relative posterior disc displacement. We reviewed the possible causes, signs and symptoms, and treatment for difficulty in closing mouth with related literatures.