Associations of sleep bruxism with age, sleep apnea, and daytime problematic behaviors in children

ObjectivesThe aims of this study were to investigate the prevalence of sleep bruxism in children in Japan, and its relationships with sleep-related factors and daytime problematic behavior. Subjects and MethodsGuardians of 6023 children aged 2-12years completed the Japanese Sleep Questionnaire. Multiple regression analysis and structural equationmodeling were performed. ResultsSleep bruxism was reported in 21.0% children (n=1263): the prevalence was highest in the age group of 5-7years (27.4%). Multiple regression analysis showed that sleep bruxism had significant correlations with age 5-7years (OR: 1.72; P<0.0001), Moves a lot during sleep' (OR: 1.47; P<0.0001), sleeps with mouth open' (OR: 1.56; P<0.0001), and snores loudly' (OR: 1.80; P<0.0001). In structural equationmodeling, sleep bruxism had a significant but weak direct effect on daytime problematic behavior, while sleep bruxism significantly correlated with obstructive sleep apnea, which had a higher direct effect on daytime problematic behavior. ConclusionsSleep bruxism was reported in 21.0% of Japanese children and had independent relationships with age, movements during sleep, and snoring. A comorbidity of sleep-disordered breathing might be related to daytime problematic behavior in children with sleep bruxism.