The tongue and airway.

Patency of the upper airway during sleep depends on a balance of forces. This article summarizes recent research undertaken by the author in the areas of tongue, soft palate and airway volume, tongue and pharyngeal edema, genioglossus muscle activity, and mandibular repositioning appliances. Three-dimensional relationships between airway, soft palate, and tongue can be quantified with accuracy, and such analyses may be of significant diagnostic importance.