Snore Guard is a mandibular advancement device that works by aligning your jaw in a comfortable forward position keeping your airway open and preventing vibration that cause snoring. With patented Air Flow Technology, the mouthpiece allows you to breathe comfortably through your mouth when you sleep. Snore Guard has been used in clinical setting since 1989 but in the United States, you will have to ask your dentist about a prescription for the device and it will have to be professionally fitted by a dentist. Conversely, if you live in Canada, no prescription is necessary.