What Are Temporomandibular Disorders?
Today, researchers generally agre that temporomandibular disorders fall into three main categories: • myofascial pain, the most common form of TMD, which is discomfort or pain in the muscles that control jaw function and the neck and shoulder muscles; • internal derangement of the joint, meaning a dislocated jaw or displaced disc, or injury to the condyle; • degenerative joint disease, such as osteoarthritis or rheumatoid arthritis in the jaw joint. A person may have one or more of these conditions at the same time. What Causes TMD? We know that severe injury to the jaw or temporomandibular joint can cause TMD. A heavy blow, for example, can fracture the bones of the joint or damage the disc, disrupting the smooth motion of the jaw and causing pain or locking. Arthritis in the jaw joint may also result from injury. Other causes of TMD are less clear. Some suggest, for example, that a bad bite (malocclusion) can trigger TMD, but recent research disputes that view. Orthodontic treatment,
