An oral appliance for users of continuous positive airway pressure (CPAP) machines. CPAP users who use a nose-only mask experience a flow of pressurized air out the mouth if the mouth is open. This causes the mouth to dry out and allows the return of obstructive sleep apnea. The oral appliance forms a seal in the users mouth that prevents the flow of air out of the mouth, which restores full function to the CPAP machine.
