ObjectivesThis study aimed to evaluate the therapeutic effcacy of custom-made mandibular advancement devices (MAD) in the control of primary snoring and sleep apnea and to correlate with anatomical changes identified through imaging tests.MethodsPatients (n = 17) diagnosed with sleep apnea or primary snoring were included in this study and subsequently treated with MADs. Changes were assessed using a polysomnographic study (PSG), the Epworth Sleepiness Scale (ESS), and an imaging study with computed tomography scanning (CT). Studies were performed before and after the use of MAD. Anteroposterior measurements were taken in the sagittal plane at the hard palate, glottis, and supraglottic levels along the hard palate axis. Afterward, measurements were taken in the axial plane at the same levels along the hard palate axis.ResultsFrom the six recorded measurements, the airway caliber increased by five. However, these changes were significant only in two measurements (sagittal hard palate and axial supraglottic). Snoring was controlled in 16 of the 17 subjects. From these sixteen, 12 subjects had a correct opening of the airway at the hard palate level. Moreover, daytime sleepiness decreased in all subjects.DiscussionPresent results suggest that sagittal hard palate and axial supraglottic opening after use of MAD are mainly responsible for eliminating snoring and improve sleep apnea.