MATRx is a test carried out in a sleep lab that helps a physician more accurately prescribe oral appliance therapy for obstructive sleep apnea, reports Fox 13 Salt Lake City.

During the MATRx test, patients are fitted with temporary dental trays that are attached to a small, remote-controlled device. A sleep technician will gently move the patient’s lower jaw in small increments while they sleep. The test results will tell the physician if an oral appliance is right for the patient and the exact jaw position needed to treat the sleep apnea.