Effects of Rapid Palate Expansion Treatment in Growing Oral Respiratory Patients: Functional Assessment of the Upper Airway Using Active Anterior Rhinomanometry

This retrospective study aims to further investigate the effects of rapid maxillary expansion (RME) treatment on respiratory function in growing patients with contracted upper airways, by assessing nasal resistance using active anterior rhinomanometry (AAR). Methods: At T0 (pre-RME), 122 orthodontic patients aged 5 to 12 years, exhibiting oral breathing and/or snoring along with maxillary contraction, underwent AAR with a mask using the ATMOS Rhino 31 rhinomanometer. Additionally, the SRDB or PSQ-SRDB Questionnaire was utilized to validate the orthodontic history of obstructive sleep apnea syndrome (OSAS). If AAR results at T0 were clinically significant, they were repeated at T1, corresponding to a period of three months after screw fixation, to evaluate changes in nasal resistance values between pre- and post-treatment. Results: The study group comprised 42 oral respiratory patients with a mean age of 7.71 years, suspected of pediatric OSAS. Although the questionnaires did not yield statistically significant results, the therapy induced an overall reduction in airflow resistance values from both nostrils (−24.63% in the right nostril; −26.65% in the left nostril). Conclusions: This study demonstrates the beneficial effects of orthodontic treatment with RME on nasal function in terms of airflow resistance in cases of maxillary contraction.