The most common sleep disorder is insomnia. Insomnia represents difficulty in initiating and/or maintaining sleep along with daytime tiredness and impairment. Of note to the dentist, sleep bruxism would fall under the umbrella of a sleep movement disorder.
The topic at hand is sleep apnea. Sleep apnea is classified under sleep breathing disorders (SBD). These disorders range from basic snoring to sleep apnea-hypopnea syndrome (SAHS). While snoring may not always present with adverse effects, SAHS is associated with daytime sleepiness and cognitive issues and an increased risk of developing health issues. Central sleep apnea is a form of SAHS which features a diminished central nervous system drive to breathe. Conversely, obstructive sleep apnea (OSA) implies a mechanical impedance to upper airway airflow. It is in this OSA arena that the dental profession has expanded its service line. While there are several ways to manage OSA, one of the management strategies involves use of a specialized oral appliance.
OSA is a result of recurrent episodes of complete or partial blockage of the upper airway despite respiratory effort. Apnea is a cessation of breathing attributed to complete airway obstruction during sleep. Hypopnea involves episodes of labored breathing or a low respiratory rate that does not meet metabolic needs and is attributed to partial obstruction of the airway.
Per the American Academy of Dental Sleep Medicine (www.aasm.org), apnea and hypopnea can be further defined: