A 62-year-old woman was referred for SPECT brain blood flow study with a diagnosis of possible dementia or depression. Findings within the brain were noncontributory, but extraneous structures with high blood flow were detected within the soft tissues of temporal regions and face. On questioning, the patient stated that she had sleep bruxism, with gnashing and grinding of her teeth. This did not occur during waking. Bruxisms and its consequences, with effects on the teeth and jaws, are a problem of importance to oral surgeons and dentists. There is considerable active research into methods of treatment of sleep bruxism.