Abstract
Objectives : Patients with obstructive sleep apnea （OSA） have been reported to have narrowed airways during sleep and a reduced capacity to expand the upper airway. Therefore, we examined the oral function of patients with OSA and healthy controls by measuring their maximum tongue pressure and evaluating the results of a questionnaire survey on sleep status.
Methods : Twenty-nine patients were enrolled in the OSA group and 29 in the control group. Each participant completed a questionnaire on sleep status. Tongue pressure was measured three times, and the highest value was defined as the maximum tongue pressure （MTP）.
Results : The OSA group had significantly higher percentages of mouth-opening during sleep and xerostomia upon awakening than did the control group （p＝0.01 and p＜0.001, respectively）. The OSA group also had significantly lower MTP than those in the control group （p＝0.004）, and male patients in the OSA group had significantly lower MTP than those in the control group （p＝0.0314）.
Conclusions : These results suggest that the activity of the genioglossus and other oral muscles is lower in patients with OSA than that in healthy participants. Anatomical sex differences may influence the mechanism of tongue pressure development and the effectiveness of treatment with oral appliances. Myofunctional therapy as an adjuvant therapy can help to improve respiratory function during sleep by increasing the strength of the tongue muscles and upper airway dilator muscles, which also enlarge the upper airway in patients with OSA who have low oral function.
