A clinical study of specific signs and symptoms of CMD in bruxers classified by the degree of severity

Two hundred and seventy-six CMD patients referred consecutively for diagnosis and treatment over a period of four years were assessed. Two hundred and eleven were classified as bruxers according to the use of a questionnaire and clinical examination. One hundred (47.39%) presented clinical characteristics of mild bruxers, 66 (31.27%) presented moderate bruxism and 45 (21.32%) demonstrated severe bruxism. Severe bruxers presented the lowest degree of jaw opening (39.21 mm) and highest prevalence of capsulitis (97.77%), retrodiskal pain (84.44%) and disk-attachment pain (48.88%). As compared to the mild and moderate groups, severe bruxers also demonstrated significantly higher prevalence of protective splinting and transient locking or recent history of intermittent locking, masticatory pain, reciprocal clicking and signs and symptoms of Myofascial Pain Dysfunction Syndrome (MPDS). Because higher prevalence of specific muscle and joint disorders were observed in bruxers and such prevalence was progressive from the mild to the moderate and severe group, it may be concluded that bruxing behavior is a significant factor in the etiology and progression of muscle and joint disorders. Based on the review of the literature, the analysis of our data in comparison to other studies allowed us to conclude that severe bruxers are more impaired by muscular and joint disorders as compared to mild and moderate bruxers.