Orofacial Myofunctional Therapy to Treat Residual Obstructive Sleep Apnoea in Children Treated with Adenotonsillectomy and Maxillary Expansion: An Interventional Study

Background: In children with residual obstructive sleep apnoea (OSA) despite combined adenotonsillectomy (TA) and semi-rapid maxillary expansion (SRME), the optimal further management remains unclear. This study evaluated the effect of a 12-month programme of orofacial myofunctional therapy (OMFT) on residual OSA in this population. Materials and Methods: In this retrospective cohort study, 80 children (aged 7–9 years) with polysomnography-confirmed residual OSA (respiratory disturbance index [RDI] ≥ 1 event/h) after combined TA and SRME were followed for 12 months. Forty-one children completed a 12-month course of OMFT, and 39 did not, due to compliance concerns, cost/access barriers, or parental preference. RDI at 12-month follow-up (RDIfinal) was compared between groups by t-test and by a covariate-adjusted general linear model. Results: Mean baseline RDI did not differ between groups (p = 0.21). At follow-up, mean RDIfinal was 0.49 events/hour in the OMT group versus 5.26 in controls (p < 0.001; Cohen’s d = 3.64), a difference that persisted after adjustment for treatment order, sex, age, race, and BMI (p < 0.001). Conclusions: A 12-month OMT programme was associated with near-normal respiratory indices in children with residual OSA after combined TA and SRME, while untreated residual OSA showed mild deterioration. Given the non-randomised design, this should be interpreted as a strong association rather than a confirmed causal effect, and a randomised trial is warranted.