John P. Blazic, DDS - Oral and Maxillofacial Surgery

The temporomandibular joint (TMJ) is a small joint located in front of the ear where the skull and lower jaw meet, which allows the lower jaw (mandible) to move and function.

TMJ disorders have a variety of symptoms. Patients may complain of earaches, headaches and limited ability to open the mouth. They may also complain of clicking or grating sounds in the joint and feel pain when opening and closing the mouth. What must be determined, of course, is the cause.

What Causes TMJ Disorders?

Arthritis is one cause of TMJ symptoms. It can result from an injury or from grinding of the teeth at night. Another common cause involves displacement or dislocation of the disc that is located between the jawbone and the socket. A displaced disc may produce clicking or popping sounds, limit jaw movement, and cause pain during opening and closing of the mouth. There are also conditions such as trauma or rheumatoid arthritis that can cause the parts of the TMJ to fuse, preventing jaw movement altogether.

	Whiplash causes the muscles of the neck to be jarred and pulled violently, often resulting in ligament tears, stretching of structures to their limits and discal tearing. All can lead to the development of TMJ symptoms.
	Bruxism, the grinding of teeth, usually occurs during sleep. Clenching can occur throughout the day or night. Both can be directly related to TMJ, either as a trigger for muscle spasms or as a result of malocclusion. Constant grinding also causes pressure on the TMJ. Bruxing can put pressure on the articular disc, squeezing out synovial fluid and robbing it of lubrication.
	When a tooth is lost, the teeth around it tend to shift to fill the space. This change can alter the way the teeth gear in relation to the joint, causing symptoms to develop. Malocclusion is also a very common cause of the TMJ syndrome. Malocclusion is the abnormal contact of opposing teeth with respect to the temporomandibular joint that interferes with the efficient movement of the jaw during mastication. It is one of the most frequent triggers of TMJ syndrome. Malocclusoin, even on a minute scale can trigger the spasm of muscles, resulting in pain.

Sometimes The Joint Itself Is The Problem

Stress may trigger pain in the jaw muscles that is very similar to that caused by TMJ problems. Such patients frequently clench or grind their teeth at night causing painful spasms in the muscles and difficulty in jaw movement. Patients may also have a combination of muscle and joint problems. That is why diagnosing TMJ disorders can be complex and may require different diagnostic procedures.

Determining the cause of a TMJ problem is important, because it is the cause that guides the treatment.

The TMJ, like any other joint, is susceptible to any of the systemic diseases. Immune disorders such as osteoarthritis, rheumatoid arthritis, psoriatic arthritis and systemic lupus erythematosus and electrolyte imbalances can produce inflammation and muscle cramping in the TMJ. In addition, viral infections can cause damage to the surfaces of the TMJ.

The joint, in addition to being a ball and socket joint, glides forward and backward. When functioning correctly, the articular cartilage lies between the condyle head of the mandible and the roof of the joint. It normally follows the condylar head in its forward and backward movement. If the ligaments that hold the disc to the conylar head are injured, the disc can slip out of place can can no longer server as a normal cushion between the lower and upper parts of the jaw. Typically, the disc is pulled forward. Mild displacements can cause a clicking or popping sound in the joint and sometimes can be painful. Permanent damage may result from the displacements.

The Role Of The Oral And Maxillofacial Surgeon

When symptoms of TMJ trouble appear, an oral and maxillofacial surgeon should be consulted. A specialist in the areas of the mouth, teeth and jaws, the oral and maxillofacial surgeon is in a good position to correctly diagnose the problem. Special imaging studies of the joints may be ordered and appropriate referral to other dental or medical specialists or a physical therapist may be made.

Range Of Possible Treatment

The oral and maxillofacial surgeon’s treatment may range from conservative dental and medical care to complex surgery. Depending on the diagnosis, treatment may include short-term medications for pain and muscle relaxation, bite plate or splint therapy, and even stress management counseling.

Generally, if nonsurgical treatment is unsuccessful or if there is clear joint damage, surgery may be indicated. Surgery can involve either arthroscopy (the method identical to the orthopaedic procedures used to inspect and treat larger joints such as the knee) or repair of damaged tissue by a direct surgical approach.

Once TMJ disorders are correctly diagnosed, appropriate treatment can be provided.