Cephalometric changes associated with MAD therapy

Study objectives: The main objectives of this study were to assess the effect of mandibular advancement device (MAD) therapy on the upper airway morphology, as well as the occurence of dental and skeletal side effects following 1-year MAD therapy in patients with mild to moderate obstructive sleep apnea (OSA). Methods: In this study we included 15 patients with mild to moderate OSA treated with MAD therapy. All subjects underwent sleep study and lateral cephalometric radiography at baseline and at 1-year follow-up. Lateral cephalograms were analyzed with respect to relevant variables. Results: MAD therapy reduced apnea-hypopnea index (AHI) from 22.9±5.9 to 9.7±4.5 events/h ( P <0.001) after 1-year of therapy. Oral area enclosure (3697.0±372.4 vs. 3381.5±336.4 mm2, P <0.001), superior airway space width (8.9±2.0 vs. 10.0±2.0 mm2, P =0.039), soft palate width (10.9±1.0 vs. 9.8±1.4, P =0.005) and length (45.4±3.8 vs. 43.9±4.2 mm, P =0.033) were significantly larger with the MAD intra-orally. Additionally, the tongue length decreased (84.1±5.3 vs. 80.7±5.9 mm, P =0.002), while the tongue height increased significantly (27.0±2.4 vs. 29.9±2.5 mm, P =0.003) with the MAD intra-orally. There were no significant changes in skeletal and dental cephalometric variables after 1 year of MAD therapy. Conclusions: Our results show significant enlargement of the upper airway dimensions with the MAD intra-orally in patients with mild to moderate OSA. Although there were no significant changes in skeletal and dental cephalometric variables after 1 year of MAD therapy, close follow-up during MAD therapy is advisable to prevent potentially relevant occlusal changes.