Do You Have TMJ? Get diagnosed and receive treatment. TMJ is the abbreviation for the temporomandibular joint—the connection between the lower jaw (mandible) and the skull. When things are working normally, this joint opens and closes even and smoothly. Your teeth and jaw close and interact with perfect alignment. Other times, however, things can get a little "out of whack." TMJ disorders can cause jaw pain, clicking or popping within [...]