The tightening created by the device also prevents the tissues of the upper airway from vibrating as air passes over them—the most common cause of snoring.

These include the polysomnographic indexes of OSA, subjective and objective measures of sleepiness, blood pressure, aspects of neuropsychological functioning, and quality of life.

[7] The medical dental sleep appliance, or MDSA, was clinically proven to conclusively show in a large and complex randomized controlled study that CPAP and MAS are effective in treating sleep-disordered breathing in subjects with AHI 5–30.

[10][11] Long-term use is not associated with temporamandibular disorders but was associated with permanent changes in how the upper and lower teeth meet, and the appliances needed about 0.8 repairs/relines per year.

[citation needed] Patients may pay around $1900 out of pocket to secure these devices, and, in the US, some health plans do not cover these costs.

[15] Adherence to oral appliance is strongly associated with patient reservations regarding the effects of the device on teeth, possible lack of efficacy, and discomfort.