A device for treating sleep apnea, the device comprising an upper portion, a lower portion and an intermediate portion, the upper portion configured to be placed on at least one tooth of the upper jaw of a patient, the lower portion being configured to be placed on at least one tooth of the lower jaw of the patient, wherein the intermediate portion is configured to couple the upper and lower portions together when placed on the teeth of the upper and lower jaws of the patient to maintain a relative position of the upper and lower jaws, the device further comprising at least one fastening member, the fastening member being configured to engage at least one interdental space of each of the upper and lower jaws to fasten the upper and lower portions to the teeth of the upper and lower jaws, respectively.