Temporo-Mandibular Disorders (TMD) FAQs

Jaw ache? Facial pains? Headaches?

For patients, jaw problems are often related to the way our teeth meet and slide against each other. Our web site can help you to understand your pain problem as well as explain how your problems can be treated. We can also help you find a dentist in your area who treats dental occlusion and TMJ problems (TMD).

For Dental Professionals, we offer advice, education and training in the understanding and treatment of restorative issues and pain conditions relating to abnormal function.

What does TMJ/TMD mean?

TMJ refers to the Temporo-mandibular Joint, or jaw joint. You have a pair of these joints, one on each side of the head between the lower jaw (mandible) and the side (temporal) bone of the skull, just in front of the ear.The TMJ’s function is to allow the lower jaw to move so that you can chew and swallow, speak, yawn and do all the other normal jaw movements. This joint also allows you to clench and/or grind your teeth. The temporo-mandibular joint is a synovial joint and includes ligaments, tissue between the jawbone and the ear canal and a fibrous disc which sits between the head of the mandible (condyle) and the joint surface (articular surface) of the skull.

TMD stands for Temporo-Mandibular Disorders and includes a whole range of conditions which can affect the joint. Some clinicians will use the term TMJ to refer to these disorders.

The temporo-mandibular joint is different from the body’s other joints. The combination of hinge and sliding motions makes this joint among the most complicated in the body. Also, the tissues that make up the temporo-mandibular joint differ from other synovial joints, like the elbow or hip.

Because of its complex movement and unique makeup, the jaw joint, its associated muscles and other structures give rise to a variety of unique conditions as well as those conditions which can affect all the joints.

I’ve heard about Botox being used to treat TMD, is that true?

Botox™ (botulinum toxin type A) is a drug made from the same bacterium that causes food poisoning. Used in small doses, Botox injections can actually help alleviate some health problems. The Food and Drug Administration (FDA) has approved Botox for the treatment of certain eye muscle disorders, cervical dystonia (neck muscle spasms), and severe underarm sweating, as well as for limited cosmetic use.

Botox has not been approved by the FDA for use in TMJ disorders. Research is under way to learn how Botox specifically affects jaw muscles and their nerves. The findings will help determine if this drug may be useful in treating TMJ disorders.

What is a splint?

Splints and Appliances

Over the years dentists have devised many different types of appliances from small jig types such as the Lucia Jig or NTI-TSS appliances through partial coverage (of the teeth)and sectional appliances to full coverage appliances including centric stabilization and anterior repositioning appliances. The terms ‘splint’ and ‘appliance’ are interchangeable.

NTI-TSS Appliances

These appliances are quite small and worn over the upper front teeth. They are described as an enhanced deprogrammer, designed to stop the canine (cuspid) teeth from occluding and thus reduce the intensity of clenching. They are worn by the patient at night. Some clinicians worry they may cause excessive loading of the TMJs.

Stabilisation Splints

Your doctor or dentist may recommend an oral appliance, also called a stabilization splint or bite guard, which is a plastic guard that fits over the upper or lower teeth. Stabilization splints are the most widely used treatments for TMJ disorders.

They are sometimes called full-coverage appliances, Tanner appliances, Michigan splints or centric relation splints. If a stabilization splint is recommended, it should be regularly checked by your clinician and should not cause permanent changes in the bite. If a splint causes or increases pain, stop using it and see your health care provider.

Anterior Repositioning Appliances.

These type of appliances are designed to bring the jaw, including the condyle forward (and down) and in doing so, allow the disc to come back into it’s correct relationship between the head of the condyle and the articulating surface of the skull. This is known as ‘recapturing the disc’.

Treatment with these type of appliances may take several months and the concept is to keep the disc in place for long enough so that the disc arrangement ‘heals’ and the disc becomes properly functional again. Increasingly the evidence is that any change is temporary and the disc dislocates again with time.

The conservative, reversible treatments described are useful for temporary relief of pain – they are not cures for TMJ disorders. If symptoms continue over time, come back often, or worsen, tell your doctor.

What types of surgery can be carried out?

Oral and maxillofacial surgeons basically have these surgical options:

  • Arthrocentesis
  • Arthroscopy
  • Arthroplasty
  • Partial joint replacement
  • Total joint replacement

In arthrocentesis, the surgeons place two needles around the joint space, then flush and irrigate the joint, getting rid of scar tissue and fibrous matter that is interrupting the joint. Arthroscopy is a procedure where a small endoscope is placed inside the joint for diagnostic purposes and to treat inflammation and discs that are “stuck” in position or displaced.

For more serious disorders where the disc is badly displaced an open arthroplasty can be performed to repair, reposition or remove the disc. Only in cases where there is severe late-stage degeneration of the disc and condyle is total joint replacement considered.

However, think long and hard and seek several opinions before undertaking surgery on this difficult area. Post-surgical results are often disappointing.

My jaw clicks, should I be concerned?

There is no evidence that clicking sounds without pain in the jaw joint lead to serious problems. In fact, jaw clicking is common in the general population. Most clinicians believe that jaw noises alone, without other symptoms such as pain or limited jaw movement, do not indicate a TMJ disorder and do not warrant treatment. It is important, though, to note if the click is changing in timing or intensity or if it’s associated with any discomfort or difficulty in opening. If so you should see your dentist.

How are the majority of TMD patients treated?

The majority of patients with TMD do not require surgery. They can be treated conservatively with one or a combination of the following:

  • Soft diet
  • Rest
  • Hot/cold pack applications
  • Mouth splints or appliances
  • Physical therapy
  • Anti-inflammatory medications
  • Muscle Relaxants
  • Analgesics (pain medications)
  • Dental treatment including:
  • Bite adjustments including equilibration
  • Restorations
  • Orthodontics

Generally surgery is avoided but patients who have a problem with the joint itself, such as a displaced disc, or a deficiency with the head of the jawbone that does not respond to conservative care, may be candidates for surgery.

What causes TMD?

How jaw joint and muscle disorders progress is not clear. Symptoms worsen and ease over time, but what causes these changes is not known. Many people have relatively mild forms of the disorder. Their symptoms improve significantly, or disappear spontaneously, within weeks or months. For others, the condition causes long-term, persistent and debilitating pain.

Trauma to the jaw or temporo-mandibular joint plays a role in some TMJ disorders. But for most jaw joint and muscle problems, clinicians don’t know the causes. For many people, symptoms seem to start without obvious reason. There is no conclusive evidence that a bad bite or orthodontic changes can trigger TMJ disorders. However there is anecdotal evidence and many dentists believe there is a relationship in some people. The condition is more common in women than men and there may be a hormonal link.

The roles of stress and tooth grinding as major causes of TMJ disorders are also unclear. Many people with these disorders do not grind their teeth, and many long-time tooth grinders do not have painful joint symptoms. Scientists note that people with sore, tender chewing muscles are less likely than others to grind their teeth because it causes pain.

Researchers also found that stress seen in many persons with jaw joint and muscle disorders is more likely the result of dealing with chronic jaw pain or dysfunction than the cause of the condition.

What are the signs and symptoms?

A variety of symptoms may be linked to TMJ disorders. Pain, particularly in the chewing muscles and/or jaw joint, is the most common symptom. Other likely symptoms include:

  • radiating pain in the face, ear, jaw, or neck,
  • jaw muscle stiffness,
  • limited movement or locking of the jaw,
  • painful clicking, popping or grating in the jaw joint when opening or closing the mouth,
  • a change in the way the upper and lower teeth fit together.

What are TMJ disorders / TMD?

Disorders of the jaw joints and chewing muscles can come in a whole range of types, as can the individual’s response. Clinicians generally agree that the conditions fall into three main categories:

  1. Myofascial or muscle pain, the most common temporo-mandibular disorder, involves discomfort or pain in the muscles that control jaw function
  2. Internal derangement of the joint can involve a displaced disc, dislocated jaw, or injury to the condyle
  3. Arthritis refers to a group of degenerative/inflammatory joint disorders that can affect the temporo-mandibular joint

A person may have one or more of these conditions at the same time. Some people have other health problems that co-exist with TMJ disorders, such as chronic fatigue syndrome, sleep disturbances or fibromyalgia, a painful condition that affects muscles and other soft tissues throughout the body. It is not known whether these disorders share a common cause but there may be a link.

People who have a rheumatic disease, such as rheumatoid arthritis, may develop TMJ disease as a secondary condition. Rheumatic diseases refer to a large group of disorders that cause pain, inflammation, and stiffness in the joints, muscles, and bone.

Both rheumatoid arthritis and some TMJ disorders involve inflammation of the tissues which line the joints. The exact relationship between these conditions is not known.