Temporomandibular joint and muscle disorders, commonly called "TMJ," are a group of conditions that cause pain and dysfunction in the jaw joint and muscles that control jaw movement.
Researchers generally agree that the conditions fall into three main categories:
- Myofascial pain involves discomfort or pain in the muscles that control jaw function.
- Internal derangement of the joint involves a displaced disc, dislocated jaw, or injury to the condyle.
- Arthritis refers to a group of degenerative/inflammatory joint disorders that can affect the temporomandibular joint.
A person may have one or more of these conditions at the same time.
Some estimates suggest that TMJ disorders affect over 10 million Americans. These conditions appear to be more common in women than men.