RESUMEN
<p><b>OBJECTIVE</b>To analyze the sleep electrophysiological changes and the sleep structure changes in children with bruxism by use of the polysomnography.</p><p><b>METHODS</b>Twelve children with severe bruxism and 11 children who had no systemic diseases or sleep disorders were selected for polysomnography.</p><p><b>RESULTS</b>The proportion of nonrapid eye movements sleep (NREMS)II and NREMS IV stages in bruxism group were (45.7 ± 7.1)% and (19.2 ± 4.9)%, while the control group were (52.9 ± 5.8)% and (13.3 ± 5.3)% respectively. The sleep efficiency and the latency of sleep were (84.0 ± 8.0)% and (39.33 ± 28.73) min in bruxism group, and (94.0 ± 3.7)% and (10.27 ± 7.57) min in the control group respectively. The difference was statistically significant.</p><p><b>CONCLUSIONS</b>The sleep structure is inordinate in bruxism children.</p>