Hyperactivity of Jaw Muscles causing TMD

The following symptoms are characteristic of TMD

1) Jaw pain

Common symptom of pain in and around the jaw joint. This pain is usually felt while you are opening and closing your jaw, but can also occur while you are resting. The pain is often of a dull ache nature. The muscles of the jaw may ache when the jaw is moved during opening and closing movements. There may be stiffness of the muscles of the face.

2) Jaw noise

Clicking, popping or grating noises may often be heard by you when opening or closing your mouth. The clicking noise is a result of the disc (pad of tissue between the head of condyle and fossa ) slipping out of place, sticking or malfunctioning. It is reassuring to know that clicking sounds are quite common and are seldom significant. However if this is accompanied by pain or grating noises this involves further investigation.

3) Difficulty opening/closing or deviated movements

Normal joints open and close quite smoothly. However if there is some injury, pressure or degenerative process, the opening may be hampered or deviated. The disc may begin to catch, stick or become displaced, thus limiting the range of jaw movement. This is called TMJ internal derangement. Single occurrences of jaw locking are usually not worrisome but repeated disc dislocation may require further investigation.

4) Chewing and biting difficulty

Uncomfortable jaw opening and closing often restricted during eating, yawning or other activities may occur.

5) Headache

Many TMDs may produce headaches of varying severity as symptoms. Jaw muscle contraction is often associated with long term headaches. TMDs often contribute to or aggravate a pre-existing headache that is not of temporomandibular origin.

The above symptoms may occur in the following pattern :

- Symptoms may occur on one or both sides of the face and at times, may cause or be related to pain in other areas of the face, head and jaws.

- Symptoms may develop soon after an injury to the face or jaws.

- Symptoms may develop with an increase in habitual muscle overuse and /or stress level

- Symptoms developing in association with related medical problems.

What causes TMD

Most of the reasons why your jaw and face hurt are not life threatening, but the pain may be distressing. What are the various factors that may contribute to TMD.

BRUXISM

Grinding and clenching of the jaws are common and can occur during sleep, and also under stress of habit. If you have this condition you will notice that your jaw and face may suffer muscle fatigue and your teeth may exhibit wear facets. Sometimes they are habitual, and thus you may be unaware of it. It is commonly associated with stress and anxiety.

BITE or OCCLUSAL ALTERATIONS

Malocclusion (poorly aligned teeth or teeth relationship) is one factor that has to be considered which may aggravate or contribute to the development of TMD. This factor as a causative factor for TMD is still not very well understood.

INJURIES

Injury to the muscles of the jaw and joint can be a cause of TMD. These may include violent blow to the face and /or jaw, sports incidents, biting on hard food or unexpected hard particle, extreme opening in yawning to name just a few.

STRESS AND ANXIETY

Everyday stressful lifestyles may cause the development of a TMD. Often ,muscle soreness occurs when jaw or facial muscle is overused or stretch. A viscous circle of stress, overuse of muscles causing tightness, joint limitation of movement and its associated pain is created.

ARTHRITIS

Osteoarthritic changes which develop in other body joints may affect the temporomandibular joint. Arthritis can cause the degeneration of the bone in the TMJ and erosion of the condyle, which can lead to TMD.

Management of TMD

This involves a series of questionnaire on the profile of patient and medical history. In the clinical examination, it usually involves the measurement of the range of opening and side movements of the jaw; identifying the type of noises the joint makes, the muscles of the jaws and neck are tested for function and dysfunction, and the evaluation of the teeth and the way your teeth come together. Further investigation with radiographs and specialized tests including MRI, plaster cast studies of your teeth may also be required depending on the case.

What are the treatment options available?

This may involve a team approach involving multidisciplinary management. Depending on the case the following are options.

* Patient education and self-care on the TMD condition

* Stress management and relaxation techniques for behavior modification.

* Medications

* Physical therapy ( Heat and SWD, ultrasound , jaw exercises etc)

* Splint appliance therapy ( wearing of plastic night guard and specialized acrylic splints)

* Surgery

* Pain management centre referral.

Occlusal Splint Therapy

Acrylic Splint

The objectives of any treatment is to reduce pain and limit its recurrence, restore a reasonable comfortable function, supervise a program of self-care and prevention of further TMD.

Contributed by A/Prof Keng Siong Beng