Disorders of the jaw joint

The Temporo-mandibular joint (TMJ)

The jaw joint is also known as the tempero-mandibular joint or TMJ. It can be felt by placing your fingers just in front of your ears, and opening and closing your mouth.

The joint allows the jaws to open, close, and move to the side and forward. It plays an important role in jaw functions such as talking, chewing and yawning. It is one of the most complex and frequently used joints in the body.

TMJ Disorders

A TMJ disorder may affect one or both joints, often causing pain and limiting jaw function.

TMJ disorders are common, with about 70% of people being affected at some time in their lives. Most symptoms of TMJ disorders are mild and do not need treatment. As in other joints of the body, symptoms often go away with time.

Causes of TMJ Disorders

While the cause of a TMJ disorder is often unknown, various factors can aggravate a TMJ disorder, such as:

missing teeth
grinding and clenching of teeth
emotional and physical stress
tension in the jaw muscles
injuries such as fractures and dislocations of the TMJ
osteoarthritis or rheumatoid arthritis
wrongly shaped fillings, crowns or bridges

The Normal Anatomy Of The TMJ

Diagnosis of TMJ Disorders

An accurate diagnosis is important to ensure that the right treatment is undertaken.

Your dentist will make a diagnosis based on a clinical examination and your medical and dental history. To assist with diagnosis, your dentist may recommend taking plaster moulds of your teeth to see if your bite is correctly balanced and x-ray films to see if the joints are the correct shape and to eliminate the presence of fractures or dislocation.

X-rays of right and left TMJs

Symptoms of TMJ Disorders

TMJ disorders in different people can cause different symptoms that may vary from mild discomfort to severe pain. For example, pain may be sharp, searing and intermittent, or dull and constant.

Symptoms of a TMJ disorder may include:

limited jaw opening
difficulty in opening the mouth
a stuck or 'locked' jaw
clicking, grating or popping noises from the jaw joint
pain when chewing or yawning
pain when opening the jaw widely
pain in or around the ears and cheeks
headaches and, occasionally, migraine-like headaches and nausea
earaches, loss of hearing or ringing in the ears
face, neck, back and shoulder pain
a feeling of muscle spasms
toothache
clenching and grinding of teeth
an uncomfortable bite

If you have any concerns about your jaw joints, please call us or visit our website to request a consultation with one of our experienced clinicians.

Treatment of TMJ Disorders

TMJ disorders are best treated conservatively using treatment methods that do not have any permanent effect on the teeth and jaw joint. As TMJ disorders are often temporary, simple treatment methods are used whenever possible to help reduce symptoms and restore jaw function. Relief from symptoms may take time, particularly if the disorder has developed over a long period.

occlusal splints (also known as bite planes) may be used to take pressure off the jaw joints and teeth
modified diet - to rest the jaw, eat only soft foods and try to chew on both sides on the mouth. Do not favour one side
avoid extreme jaw movements e.g. yawning
physiotherapy can be helpful
muscle relaxation can be achieved by applying warm or cold packs to tender areas
relaxation and stress management
behaviour modification therapy
medication
referral to a specialist in TMJ disorders may be necessary if conservative treatment fails
surgery - rarely surgery may be required

An occlusal splint