TMD (temporomandibular disfunction) refers to pain in the joint of the jaw. Symptoms are headaches, soreness of the muscles, pain upon opening or chewing. The cause is usually grinding or clenching of the teeth. The most common treatment is fabrication of a night guard to be worn during sleep. It does not allow the teeth to grind and minimizes or eliminates pain in most cases. Other treatment may require the use of anti-inflammatory medications or, rarely, referral to a TMJ specialist.