A group of conditions that cause pain and dysfunction in the joint that connects the lower jaw (or mandible) and the bone at the side of the head (known as the temporal bone) and the muscles that control the jaw. According to the National Institute of Dental and Craniofacial Research, more than 10 million Americans may suffer from these disorders. How and why they progress is not clear. For many people, the pain goes away without treatment but some develop significant and long-term symptoms.
