Objective: We studied longitudinally the associations of craniofacial morphology, mouth breathing, orthodontic treatment, and body fat content with the risk of having and developing sleep disordered breathing (SDB) in childhood. We hypothesized that deviant craniofacial morphology, mouth breathing, and adiposity predict SDB among children.
Materials and methods: The participants were 412 children 6-8 years of age examined at baseline and 329 children aged 9-11 years re-examined at an average 2.2-year follow-up. An experienced orthodontist evaluated facial proportions, dental occlusion, soft tissue structures, and mode of breathing and registered malocclusions in orthodontic treatment. Body fat percentage was assessed by dual-energy X-ray absorptiometry and SDB symptoms by a questionnaire.
Results: Children with SDB more likely had convex facial profile, increased lower facial height, mandibular retrusion, tonsillar hypertrophy, and mouth breathing at baseline and convex facial profile, mandibular retrusion, and mouth breathing at follow-up than children without SDB at these examinations. Male gender and body adiposity, mouth breathing, and distal molar occlusion at baseline were associated with SDB later in childhood. Adipose tissue under the chin, mandibular retrusion, vertically large or normal throat and malocclusion in orthodontic treatment at baseline predicted developing SDB during follow-up of among children without SDB at baseline.
Limitations: We could not conduct polysomnographic examinations to define sleep disturbances. Instead, we used a questionnaire filled out by the parents to assess symptoms of SDB.
Conclusions: The results indicate that among children, deviant craniofacial morphology, mouth breathing, body adiposity, and male gender seem to have implications in the pathophysiology of SDB.