Polysomnographic analysis of bruxism.

The American Academy of Sleep Medicine (AASM) defines sleep bruxism as a stereotyped movement disorder characterized by clenching and grinding of the teeth during sleep. Bruxism is found in 14%-20% of children, 8% of adults <60 years old, and 3% of adults >60 years old. The mandibular movements of bruxism can be confused with rhythmic mandibular movements associated with other sleep disorders, such as arousals/microarousals, limb movement disorder, and obstructive sleep apnea/hypopnea syndrome. Polysomnography (PSG) is the study of sleep disorders based on the recording of physiological events throughout an entire night of sleep. This system involves electroencephalography, electrooculography, and electromyography of the submental/suprahyoid, tibialis anterior, mentalis, masseter, and temporal muscles, through which signs of sleep bruxism can be identified. The aim of the present study was to identify bruxism during a night of sleep in a laboratory. Thirty patients were analyzed clinically and underwent PSG. The descriptive analysis correlated apnea, arousals, and limb movements in the 12 patients who exhibited signs and symptoms of sleep bruxism. Of these patients, 4 were confirmed through PSG to have bruxism. In a comparison between the 4 patients with confirmed bruxism (PSGB group) and the 8 patients confirmed not to have bruxism (NPSGB group), the respiratory event index was lower in the PSGB group (13.17 and 17.95, respectively). The mean leg movement index was higher in the PSGB group than the NPSGB group in total sleep time (21.36 and 8.42, respectively) and in rapid eye movement sleep time (34.54 and 10.30, respectively).