INTRODUCTION: The study aimed to compare daytime sleepiness in children with severe malocclusion with healthy children with neutral occlusion (controls) and to analyze associations between daytime sleepiness and craniofacial morphology in children with severe malocclusion.

METHODS: In 120 children with severe malocclusion (73 girls, 47 boys; mean age, 11.96 years; mean body mass index [BMI] score, 18.97 kg/m2) and 35 controls (18 girls, 17 boys; mean age, 11.97 years; mean BMI score, 20.28 kg/m2), sleep and daytime sleepiness were recorded using Epworth Sleepiness Scale and Berlin Questionnaire. Occlusion was registered clinically, and craniofacial morphology was assessed on lateral cephalograms. Differences in daytime sleepiness and sleep between the groups and associations between daytime sleepiness and sleep and craniofacial morphology were analyzed by a general linear model adjusted for age, gender, and BMI score.

RESULTS: Daytime sleepiness occurred significantly more often in children with malocclusion than in control subjects (P = 0.015). There was a tendency for children with malocclusion to feel extremely tired during the day more often than controls (P = 0.054). There was no significant difference between the groups in sleeping hours during night-time, but the amount of sleep was negatively associated with age (P <0.001) and BMI score (P = 0.004). Only maxillary inclination was significantly associated with daytime sleepiness (P = 0.043).

CONCLUSIONS: Daytime sleepiness occurred significantly more often in children with severe malocclusion than in those with neutral occlusion, and the association between daytime sleepiness and craniofacial morphology may exist. The results might prove valuable in interdisciplinary collaboration between medical doctors and orthodontists in diagnostics, prevention, and treatment of children at risk for sleep-disordered breathing.