Temporomandibular Joint Dysfunction

Temporomandibular Joint Dysfunction

What is the Temporo-Mandibular Joint?

The Temporomandibular Joint (‘TMJ’), is the joint where the lower jaw (the ‘mandible’) joins the bottom of the skull (at the ‘temporal bone’), immediately in front of the ear on each side of the head. It moves every time you chew, talk and swallow. It is one of the most frequently used joints of the body. Problems affecting this joint itself are usually known as TMJ disorders. However, there are various other causes of jaw pain and so the various conditions affecting the joint are now called ‘temporomandibular disorders (TMDs)’.

The jaw joint allows movement between the jawbone (mandible) and the skull. Muscles attached to the skull and jawbone cause the jawbone to move as the mouth is opened and closed. Inside the jaw joint, there is a smooth material called cartilage, covering part of the bones. There is also a cartilage disc within the joint. The joint is lubricated by fluid called synovial fluid.

Causes of TMJ Dysfunction:

In general, TMDs are thought to have a ‘multifactorial’ cause, meaning that there are usually a number of factors contributing to the cause. These factors can be grouped into two types; problems linked to the muscles working the joint, problems inside the joint itself. Problems with the muscles may be caused by;

Bruxism

One sided chewing

Occlusion disorders

Habits such as finger sucking, pencil, lip biting.

Problems in the joint may be caused by;

Wear and tear to the inside of the joint for example, wear and tear to the cartilage. Sometimes this is due to a type of arthritis called osteoarthritis. This problem tends to affect older rather than younger people.

For example, rheumatoid arthritis and gout are both types of arthritis which may affect various joints in the body and they can sometimes affect the jaw joint.

Injury to the TMJ or to its cartilage disc can cause TMJ pain.

In each of the above circumstances, a faulty chewing pattern takes place that creates one focus of wear of the cartilage lining of the joint space. When that spot wears down, pain occurs. A form of arthritis occurs which is called TMJ Dysfunction (dysfunction means faulty or painful function).

Symptoms of temporomandibular disorders;

Pain in the joint area or nearby. The pain is usually located just in front of the ear and it may spread to the cheek, the ear itself and the temple.

Jaw movements may be reduced. Very rarely, the jaw may become ‘locked’, causing difficulty in opening or closing the mouth.

Clicks or noises can sometimes be heard coming from the jaw joint when you chew or move your mouth. These noises can be normal, so they are only relevant if you have other symptoms in the joint, such as pain or reduced movement.

Because the ear is very close to the jaw joint, some people develop ear symptoms such as; noise in the ear, sensitivity to sound, dizziness (vertigo).

Treatment for temporomandibular disorders: 

Most problems in the jaw joint can be helped with simple treatments such as painkillers and advice on how to rest the joint.

Relaxation and stress-reducing therapies and splints are sometimes suggested.

Paracetemol, aspirin or other antinflammatory medicines can be used. Antinflammatories are particularly effective for TMJ dysfunction.

An injection of a medicine called a steroid into the joint may help, when symptoms are due to inflammation in the joint.

If the jaw muscles are overactive to a severe degree (such as with a movement disorder), an injection of botulinum toxin can reduce symptoms.

For very few patients, surgical repair of the joint may be suggested.