An integrated oral appliance for treating breathing obstruction, snoring and restriction of the upper airway during sleep with a tongue restraint. Oral appliances of the invention may include an oral cavity engagement device including one or more trays, a tongue restraint with a tongue contact portion, a spring force element operatively coupled between the at least one tray and the tongue restraint, wherein the spring force element is adjustable anteriorly and posteriorly relative to the tray(s), and an air conduit inside the tongue restraint with a front opening of the air conduit extending beyond an anterior end of the tray(s) and a rear opening of the air conduit at a posterior end of the of the oral cavity engagement device configured to extend to a posterior surface of a tongue.
