Destructive bruxism: sleep stage relationship.

Despite apparent similar amounts of bruxism, two groups that had been evaluated polysomnographically differed dramatically in symptomatology. Patients with severe symptoms were referred to as the destructive bruxism group and were compared with (a) a group with sleep disturbance complaints who had bruxism and (b) a group of insomniac depressed patients chosen without regard to bruxism. It was hypothesized that not only the presence of bruxism during sleep but its pattern and sleep stage relationship were factors affecting clinical symptoms. The results indicated that the sleep stage relationship was an important factor. Patients with severe symptoms attributed to nocturnal bruxism were likely to have more bruxism in REM sleep than the other groups. These results if replicated prospectively would help explain some of the discrepancies in the literature concerning sleep stage relationship of bruxism, as well as help explain differences in symptomatology of bruxism patients.