Upper Airway Resistance Syndrome: a Combined ENT and Dental Approach

It is well accepted that obstructive sleep apnea (OSA) is not merely a simplistic anatomical imbalance of a small box (jaw) versus the over-crowding of tissue contents (namely the tonsils, tongue, palate, and lateral pharyngeal walls) within this container. Most sleep specialists agree that there is a strong complex neuro-physiological interconnected web of neurological and proprioceptor mechanism ongoing in this sleep disorder, perhaps simplified phenotypically as the PALM scale (Pcrit, arousal threshold, loop gain, and muscle responsiveness). What determines which patient would sleep through a prolonged and profound apneic event with a high arousal threshold and low muscle responsiveness versus another patient who would be easily aroused (low arousal threshold) and have frequent sleep fragmentations, no one has the answer. It has been shown that there is a complex relationship and physiological feedback mechanisms in the pathophysiology of upper airway collapse, cortical arousals, and teeth clenching in order to maintain airway patency. We are fairly clear that upper airway resistance syndrome (UARS) is the non-hypoxic sleep-disordered breathing that is closely related to cortical arousals, sleep fragmentation, psycho-somatic issues, excessive daytime sleepiness, neckaches, headaches, bruxism, and almost invariably nasal congestion.