An oral appliance is a small and comfortable acrylic device that fits over the upper and lower teeth.  It is similar to retainers used in orthodontic therapy or night guards used for grinding of the teeth at night.

At night the appliance is used while sleeping to prevent the soft tissues of the throat from collapsing and obstructing the airway.  Oral appliances work by gradually advancing the lower jaw forward, which in turn moves the base of the tongue forward.  This opens the airway to improve breathing and reduces the snoring and apneas that occur during sleep.