Your temporomandibular joint (TMJ) is the complex joint that connects your lower jaw to your skull. It’s located on either side of your face, right in front of your ears, and is composed of both hinge-like and sliding mechanisms. TMJ disorder, or TMD, is a condition that affects your temporomandibular joint and/or the muscles and ligaments attached to it. Many people use the terms TMJ and TMD interchangeably, though the former technically refers to the joint itself, while the latter refers to the condition associated with the joint.