Therefore, the investigators aim to test the effect of the Varnum mouthpiece on pharyngeal collapsibility and OSA severity in patients who identify themselves as mouth breathers. The investigators' working hypothesis is that the device will keep the lips from separating and thereby prevent oral breathing. In doing so, it may help keep the airway more patent (by promoting nasal instead of oral breathing) in self-described mouth breathers and thus reduce OSA severity. On the contrary, the investigators believe patients who do not identify themselves as mouth breathers might not benefit significantly from the Varnum device.