In some cases, the causes of TMJ, or temporomandibular joint disorder, are unknown. Other causes of TMJ include damage to the joint or muscle fatigue. A person can experience TMJ if she grinds her teeth, clenches her jaw, or chews gum excessively. Awkward positions, such as holding a phone between the ear and shoulder or leaning forward to stare at a computer monitor, can also cause TMJ.
The temporomandibular joint is located on both sides of the head, just in front of the ears. It is responsible for moving the jaw when a person opens her mouth to yawn, speak, or chew. If someone has a problem with her temporomandibular joint, she may have pain, including headaches and ear pain, trouble chewing and problems with her bite, or a locked jaw.
One of the causes of TMJ is a disc, or the part of the joint that absorbs shock, getting out of alignment. The disc can become misaligned when a person is hit in the jaw or suffers whiplash in an automobile accident. Wear on the disc is another cause of TMJ.
A punch or hard blow to the jaw is another of the causes of TMJ disorder. The punch could damage the joint or bruise nearby muscles, leading to pain in the jaw. Previously broken jaw or other facial bones are other common causes of TMJ.
People who have arthritis may also experience TMJ, as the condition damages the cartilage in the joint, leading to pain in the jaw area. Grinding the teething or clenching the jaw are other common causes of TMJ. Someone may grind her teeth because she is under stress or because it is a habit she's not even aware of. A dentist or doctor can diagnose teeth grinding by examining the wear on a patient's teeth.
Chewing problems or bite issues can also cause trouble with the temporomandibular joint. Some people may have misaligned teeth or may put strain on one part of their jaw by chewing on one side of the mouth. Chewing gum or objects that are not meant to be chewed, such as fingernails, can also disrupt a person's bite.
A patient can cope with the pain caused by TMJ by taking over-the-counter pain relievers. She may need stronger medication, such as corticosteroids, to relieve the pain. Patients who suffer from TMJ as a result of grinding their teeth may need to wear a bite guard at night to control the grinding and protect the teeth.