Sleep bruxism and temporomandibular disorders

Objectives: The aim of this study was to identify associations between sleep bruxism (SB) and temporomandibular disorders (TMD) recorded on the basis of the research diagnostic criteria of temporomandibular disorders (RDC/TMD).
Methods: Sleep bruxism was assessed using validated questionnaires, plus clinical symptoms, plus electromyographic/electrocardiography data recorded with the Bruxoff® device. A total of 110 subjects were included in the study. Fifty-eight patients were identified as bruxers and 52 as non-bruxers. The bruxers were further classified as moderate (> 2 SB and ≤ 4 SB episodes per hour) and intense bruxers (> 4 SB episodes per hour). All patients were evaluated by use of the RDC/TMD protocol. Psychosocial assessment was performed including the graded chronic pain scale, jaw disability index, a depression scale and the assessment of somatization. Study groups were compared by use of chi-squared tests with α = .05.
Results: Ten of 58 bruxers demonstrated a group I diagnosis (myofascial pain), whereas none of the non-bruxers showed a group I diagnosis (p=0.007). Group II diagnose (disc displacement) and Group III (arthralgia, arthritis, arthrosis) demonstrated no significant different prevalence for bruxers and non-bruxers. Regarding psychosocial assessment, bruxers demonstrated significantly higher levels of somatization-specific behavior (p=0.001) compared to non-bruxers.
Conclusions: The results of the present study indicated an association between myofascial pain and sleep bruxism as well as an association between somatization and sleep bruxism.