TMJ | TMD

Symptoms | Causes | Treatment

What is TMJ?

“TMJ” stands for temporomandibular joint, or the jaw joint. In fact, there are really two TMJs, one in front of each ear. The TMJ is the joint formed by the temporal bone of the skull (temporo) with the lower jaw or mandible (mandibular). These joints move each time we chew, talk or swallow. Unlike the shoulder or knee, which are ball-and-socket joints, the TMJ is a sliding joint. The sliding allows for pressure placed on the joint to be distributed throughout the joint and not just in one area. Adding to the joint’s complexity is that between the two bones that make up the TMJ (the temporo and mandibular) is a disc, just like those between the bones on your back. Made primarily of cartilage, in the TMJ the disc acts like a third bone. Because it is attached to a muscle, the disc actually moves with certain movements.

One of the difficulties with diagnosing a TMJ disorder is identifying the exact source of the problem. For example, the nerve to the TMJ is a branch of the trigeminal nerve. An injury to this nerve in the TMJ may be confused with neuralgia because the symptoms appear to be the same. The two bones of the TMJ are held together by a series of ligaments, any of which can be damaged. A damaged TMJ ligament usually results in a dislocation of the disc, the lower jaw, or both. Another possible problem may be from muscles that are connected to the bone. A muscle injury may produce pain in the TMJ or abnormal movement of the lower jaw. Careful diagnostic study and testing is needed to determine the precise source of any TMJ problem.

A TMJ disorder is simply a disruption in the action of the jaw, usually accompanied by pain. There are a number of conditions affecting the function of the jaw that can cause one of these disorders. Fortunately, because the jaw is made up of bone and other living tissue, it is alive, making it capable of repair and healing.

In this Video, Dr. Rawson Explains how Pain and Sleep Disorders are Related

TMJ Symptoms and Diagnosis

People with TMJ problems generally experience one or more of the following symptoms:

Chronic recurring headaches
Clicking, popping or grating sound in the jaw joints
Earaches, congestion or ringing ears
Limited jaw opening or locking
Dizziness
Pain when chewing
Neck and/or throat pain
Difficulty in closing the teeth together
Tired, tight jaws
Pain behind the eyes
Scalp tenderness
Swallowing difficulty
Pain in the tongue, gums or cheek muscles
Teeth grinding or clenching

Depending on the nature and severity of the problem, the evaluation of hard tissues may be accomplished using x-rays and CT scans. Soft tissue is evaluated using MRIs, Joint Vibration Analysis (JVA) and electromyography (EMG). Jaw movements are documented using the Jaw Tracker (JT). Occlusion is evaluated using the T-Scan. More information about these diagnostic technologies appears on the Treatments page.

The evaluation process will include:

Detailed Medical and Dental History
Physical Examination

Causes of TMJ

Statistics indicate that the vast majority of TMJ problems are caused by trauma. By trauma, we mean an injury as obvious as a blow to the jaw with a fist or something as subtle as a whiplash injury from a car accident that causes direct trauma to the head or jaw. 

The most common forms of trauma that cause TMD are:

  • Whiplash (cervical acceleration/deceleration)

  • Air bag deployment

  • Opening the jaw too wide

  • Bruxism

  • Bad bite (malocclusion)

  • Orthodontics

  • Ligament laxity

  • Stress

  • Systemic diseases

Whiplash (Cervical Acceleration/Deceleration)

Whiplash injuries often damage the soft tissue in the neck, back and TMJs. Usually these injuries happen when a car is hit in the rear. The violent motion of the head being thrown from a still state backwards and then forwards again often causes the mouth to be forced open. This produces stretching and/or tearing of the ligaments and connective tissues in one or both TMJs, and possibly bleeding and displacement of the disc in the TMJ. Common complaints after a whiplash injury include neck pain, neck stiffness or difficulty in turning the head, headaches (especially where the neck attaches to the head), TMJ pain, limited ability to open the mouth, TMJ noises, face and/or ear pain, change in bite, dizziness, visual changes (such as light sensitivity or blurry vision) and swallowing difficulties or hoarseness.

Systemic Diseases


Various diseases can cause or aggravate TMJ problems. Immune disorders, such as rheumatoid arthritis, psoriatic arthritis and systemic lupus erythematosus, can produce inflammation in the TMJ. Additionally, viral infections, such as mononucleosis, mumps and measles, can cause damage to the surfaces of the TMJ, which can lead to an internal derangement.

There are a number of other pain disorders that are often confused with TMJ because they involve pain in the jaw. Most common among these are:

  • Temporal Tendinitis

  • Ernest Syndrome

  • Occipital Neuralgia

  • Trigeminal Neuralgia

  • Atypical Trigeminal Neuralgia

  • Atypical Face Pain

  • Neuralgia Inducing Cavitational

  • Osteonecrosis (NICO)

Temporal Tendinitis – The “Migraine Mimic”

Temporal tendinitis has been called “the migraine mimic” because so many of its symptoms are similar to migraine headache pain. It is characterized by TMJ pain, ear pain and pressure, temporal headaches, cheek pain, tooth sensitivity and neck and shoulder pain. Treatment consists of injecting local anesthetics and other medications, a soft diet, applying moist heat, using muscle relaxants and anti-inflammatory medications, and physiotherapy. In very rare cases (less than 4%), surgery may be needed.

 

Air Bag Deployment

While air bags have undoubtedly saved lives, they have also been implicated in causing TMJ problems. Patients who have been injured with air bags often experience one or more of the following symptoms: burned or abraded skin on the chin, face or nose; almost immediate TMJ pain; swelling of the TMJs; limited mouth opening; neck pain; and change in the dental occlusion (bite).

Bruxism

Bruxism is the abnormal grinding of the teeth. Bruxism usually occurs during sleep, which is why many people don’t realize they are doing it. But when grinding continues, TMJ problems may develop. An indication that a person is grinding their teeth in their sleep is sore jaw muscles when waking. Minimally, bruxism may produce muscle pain, tooth sensitivity or worn teeth. In some cases, the pressure to the TMJ from constant grinding of teeth leads to ligament injuries, which might cause the disc to dislocate.

Stress

Stress has many effects on our bodies: some good and some bad. Physiological changes can produce muscle tightness and pain. When a person is subjected to chronic stress, these physical changes may produce harmful effects. When it comes to TMJ problems, stress is like throwing gasoline on a fire. The gasoline doesn’t produce the fire, but it does make it worse. Similarly stress intensifies TMJ problems. Muscles tighten, teeth clench, abnormal pressure is forced against the TMJ disc, and if the ligaments are weak or if the patient is one that has ligament laxity, the disc may dislocate.

 

Orthodontics

Some dentists feel that orthodontic treatment, or braces, might be a cause of TMJ. By moving teeth with orthodontic appliances, malocclusion is produced during treatment. That’s probably why many people undergoing orthodontics report sensitive teeth, pain in the jaw muscles or even bruxism. However, there is no scientific proof that orthodontic treatment produces TMJ problems, particularly once the treatment has been completed.

 

Atypical Face Pain

While the same trigeminal nerve is involved in atypical face pain, in this case the facial pain seems to affect people who are under a tremendous amount of stress or have a history of psychiatric problems.

 

Bad Bite (Malocclusion)

A bad bite, or malocclusion, may be produced by poor development of the jaws, removal of teeth without replacement, a high dental restoration, a poor fitting denture or partial denture, or a displaced TMJ disc.

 

Ligament Laxity

People who appear to be double-jointed suffer from a problem termed ligament laxity. When this occurs, a joint appears to be double – or loose. This does happen to the TMJ. Ligament laxity is a fairly common problem in active young women who suffer with TMJ problems and, often, injuries to other joints.

Ernest Syndrome

This TMJ-like problem involves a tiny ligament structure that connects the base of the skull with the mandibular or lower jaw. If injured, the structure can produce pain in the face, head, neck, temple, ear, cheek eye, throat and/or TMJ. Treatment of Ernest Syndrome, which is successful about 80% of the time, consists of injections of local anesthetic and medication (like cortisone or Sarapin), physiotherapy and, at times, the use of an intraoral splint.

 

Occipital Neuralgia

This disorder is characterized by pain radiating to one or both sides of the head, temples, cheek and forehead and particularly pain above and behind the eye.

 

Trigeminal Neuralgia

Also known as tic douloureux, this is a disorder of the trigeminal, or fifth cranial nerve. It is characterized by sharp electrical pain, which lasts for seconds. The pain is triggered by touching a specific area of the skin, as when washing, shaving, applying makeup, brushing the teeth, kissing or even from exposure to cold air. The pain is often very severe.

 

Neuralgia Inducing Cavitational Osteonecrosis (NICO)

Also known as osteocavitational lesions or Ratner’s bone cavities, this disorder produces pain similar to that of typical and atypical trigeminal neuralgia as well as referred pain patterns. There are trigger areas for the pain, which, in this case, develop directly over areas of dead bone. Generally, the lower jaw is affected more often than the upper jaw.

 

Opening the Jaw Too Wide

All joints have limitations to movement, and the TMJ is no exception. If you open wide for a long time or if your mouth is forced wide open, ligaments may be torn, swelling and bruising develop and disc dislocation may occur.

 

Atypical Trigeminal Neuralgia

In contrast to the typical type, atypical trigeminal neuralgia produces constant pain that increases or decreases in intensity. There are trigger zones, but there is also an area of dull aching. A common cause of this disorder is trauma, especially after a surgical incision or blow to the face. (June: how is it treated? does it go away or is it chronic? what do you do for it?)

 

In this Video, Dr. Rawson Explains the Treatments for TMJ

How is TMJ Treated?

At the TMJ & Sleep Therapy Office, we pride ourselves on using the most current, proven and accepted non-invasive diagnostic equipment available to help identify your particular situation and treatment needs. This encompasses leading technologies used to diagnose TMJ problems and monitor treatment progress, including:

  • Joint Vibration Analysis (JVA)

  • Jaw Tracking (JT)

  • Electromyography (EMG)

  • BioTENS and BioPAK Bite Registration

  • T-Scan II

  • Radiographs

TMJ Treatments

Joint Vibration Analysis (JVA)


This equipment (approved by the ADA) measures how well the TMJ functions while in motion. This is accomplished by placing headphones over the joints and recording the vibrations of either soft tissue or bone-on-bone grinding. Dr. Rawson feels this device is mandatory when determining what position the mandible (lower jaw bone) should be placed in therapy. This technology also serves as objective proof of what is happening to the joint as it functions and is dramatically less expensive and time consuming than an MRI.

BioTENS and BioPAK Bite Registration

This portable equipment helps reduce facial pain for many patients. BioTENS is a compact, ultra-low frequency, electrical neural stimulator that delivers a precisely regulated, rhythmic stimulus to both masticatory and facial muscles. A single pair of electrodes mildly stimulate cranial nerves that affect key muscles in the face, jaw and parts of the neck. This relaxes the muscles, thereby reducing facial pain. BioPAK Bite Registration provides key data on the patient’s different bite relationships which helps Dr. Rawson to better understand the dysfunction that may be causing or contributing to TMD.

Electromyography (EMG)


This equipment evaluates muscle tension through sensors that are placed over the patient’s head. The information it produces tells Dr. Rawson if the problem is ascending up the spinal cord from below the neck or if it is descending. This information is very important in correcting posture problems that are either the origin or the effect of the TMD. Swallowing, chewing, clenching and bite problems can also be effectively identified using EMG.

 

Jaw Tracking (JT)

Also known as electrognathography, this equipment offers the ability to track jaw movements three-dimensionally and record the point of dysfunction, all non-invasively. A headset is placed on the patient. A specialized magnet is placed inside the patient’s lower front teeth. Then a recording of the lower jaw movement is made. This information is vital for identifying the correction needed.

T-Scan II

This technology is used to precisely document a patient’s bite (occlusion). A sensor is placed in the patient’s mouth using a special handle. As the patient bites on the ultra thin sensor, the T-Scan II software scans the movement and displays the occlusion on a computer screen. The timing and force of the tooth contacts are shown in color-coded contour images. This information allows for instant diagnosis of occlusion problems.

Radiographs

This imaging technology provides x-rays of the head and neck as well as complex motions and elliptical slices of the head. These images are much more comprehensive than typical dental and cranial x-rays and are useful in determining the precise source of a TMJ problem.