TMJ (temporpmandibular dysfunction) is a condition that can involve the jaw joint, ears, head, face and teeth. The most common symptom of TMJ is a popping or clicking in front of the ear. Although pain may not always be involved, a displaced disc causes the jaw muscles to tense more than normal. This tenseness can cause facial, neck and head pain. Some patients experience “lock jaw”, where the jaw hinge catches when the patient opens his mouth. Treatments for TMJ focus on diagnosing and identifying a comfortable position for the patient’s jaw. In order to stabilize the patient’s jaw, the dentist may recommend the use customized mouthpieces, orthodontics (braces), or dental prosthetics.