Background: To evaluate the combined surgical and orthodontic treatments in children with OSA. Materials & Methods: A total of 20 subjects were enrolled. The orthodontic treatment started in order to solve the maxillary transverse discrepancy using a RPE. Dental records were taken in order to built the device in a dental technician laboratory. After one week the RPE were delivered and applied to the subjects. Oxygen saturation was recorded. The results were analysed using SPSS software. Results: The patient's parents recommended a more pleasant sleep environment free from episodes of sleep apnea at the subsequent medical assessment. Conclusion: The resolution of the condition of severe OSA can restore a physiological development of young patients.