Prevalence of malocclusions and oral dysfunctions in children with persistent sleep-disordered breathing after adenotonsillectomy in the long term.

To evaluate the prevalence of craniofacial/orthodontic abnormalities and oral dysfunctions in a population of children with persistent sleep-disordered breathing (SDB) despite adenotonsillectomy (A&T).Medical charts of 4000 SDB children operated in a tertiary hospital were retrospectively reviewed. Patients reporting persistent SDB symptoms were invited to an orthodontic/myo-functional evaluation following the Sleep Clinical Score (SCS), followed by a one-night ambulatory type III sleep study.100 non-syndromic symptomatic patients were examined (mean age 8.8±3.5), from 1-12 years after surgery (mean 4.6±3.1); 24% were overweight/obese; 69 had a sleep study. Although prevalent, oro-nasal abnormalities and malocclusions were not specifically associated with pathological sleep parameters (cartilage hypotonia 18% septal deviation 5%, short lingual frenulum 40%). Malocclusions were associated with a higher Respiratory Event Index (REI) in children under 8 only, whereas an impaired nasal dilator reflex and tongue immaturity were associated with an increased Obstructive Respiratory Event Index (OREI) in all subjects (1.72±2.29 vs. 0.72±1.22, p=0.011) and REI respectively (3.63±3.63 vs. 1.19±1.19). Male sex, phenotype, nasal obstruction, oral breathing and young age at surgery (<3 years) were significantly related to higher REI. Using the SCS >6.5 cut-off, patients with persistent sleep apnea were significantly distinct from chronic snoring (2.72±2.67 vs. 0.58±0.55 p<0.01).Oro-nasal anatomical and functional abnormalities were quite prevalent and various in persistent SDB after A&T. Nasal disuse and tongue motor immaturity were associated with higher OREI in the long term, whereas craniofacial risk factors might have a more pronounced impact at younger age.