Temporomandibular Joint Disorders (TMD)

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Infection of the temporomandibular joint (TMJ) may result from direct extension of adjacent infection or hematogenous spread of bloodborne organisms. The joint area is inflamed, and jaw movement is limited and painful. Local signs of infection associated with evidence of a systemic disease or with an adjacent infection suggest the diagnosis. X-ray results are negative in the early stages but may show bone destruction later. If suppurative arthritis is suspected, the joint is aspirated to confirm the diagnosis and to identify the causative organism. Diagnosis must be made rapidly to prevent permanent joint damage.

Treatment includes antibiotics, proper hydration, pain control, and motion restriction. Suppurative infections are aspirated or incised and drained. Once the infection is controlled, passive jaw-opening exercises help prevent scarring and limitation of motion.

Rarely, acute injury may lead to arthritis of the TMJ. Pain, tenderness, and limitation of mandibular motion occur. Diagnosis is based primarily on history. X-ray results are negative except when intra-articular edema or hemorrhage widens the joint space. Treatment includes oral corticosteroids, nonsteroidal anti-inflammatory drugs (NSAIDs), application of heat, a soft diet, and restriction of jaw movement.

The TMJ may be affected by osteoarthritis (degenerative joint disease), usually in people > 50 years. Occasionally, patients complain of stiffness, a grating sound on jaw movement, or mild pain. Crepitus may result from disk degeneration or perforation, causing bone to grate on bone. Joint involvement is generally bilateral. X-rays or cone beam CT may show flattening (eg, subchondral cysts, erosions and lipping of the condyle, suggestive of dysfunctional change, most likely due to excessive loading of the joint). Treatment is symptomatic. An oral appliance (mouth guard) worn during sleep (and possibly while awake) may help alleviate pain and reduce grating sounds.

This arthritis usually develops in people (usually women) aged 20 to 40 years with a history of trauma or persistent myofascial pain syndrome. It is characterized by limited opening of the mouth, unilateral pain during jaw movement, joint tenderness, and crepitus. When it is associated with myofascial pain syndrome, symptoms wax and wane.

Unilateral joint involvement helps distinguish secondary degenerative arthritis from osteoarthritis. Diagnosis is based on x-rays, which, as in osteoarthritis, generally show condylar flattening, lipping, spurring, or erosion.

Treatment is conservative, as it is for myofascial pain syndrome, although arthroplasty or high condylectomy may be necessary. An oral appliance (occlusal splint [mouth guard]) usually relieves symptoms. The appliance is worn constantly, except during meals, oral hygiene, and appliance cleaning. When symptoms resolve, the length of time that the appliance is worn each day is gradually reduced. Intra-articular injection of corticosteroids may relieve symptoms but may harm the joint if repeated often.

The TMJ is affected in > 17% of adults and children with rheumatoid arthritis, but it is usually among the last joints involved. Pain, swelling, and limited movement are the most common findings. In children, destruction of the condyle results in mandibular growth disturbance and facial deformity. Ankylosis may follow. X-rays of the TMJ are usually negative in early stages but often show late-stage bone destruction, which may result in an anterior open-bite malocclusion. The diagnosis is suggested by TMJ inflammation associated with polyarthritis and is confirmed by other findings typical of the disease.

Treatment is similar to that of rheumatoid arthritis in other joints. In the acute stage, nonsteroidal anti-inflammatory (NSAID) drugs may be given, and jaw function should be restricted. An oral appliance worn during sleep is often helpful. When symptoms subside, mild jaw exercises help prevent excessive loss of mandibular motion. Surgery is necessary if ankylosis develops but should not be done until the condition is quiescent.

Slowly progressive unilateral enlargement of the head and neck of the condyle causes crossbite malocclusion, facial asymmetry, and shifting of the midpoint of the chin toward the unaffected side. The patient may appear prognathic. The lower border of the mandible is often convex on the affected side. Chondroma and osteochondroma may cause similar symptoms and signs, but they grow more rapidly and may cause even greater asymmetric condylar enlargement.

This condition usually results from trauma, infection, or irradiation occurring during the growth period but may be idiopathic. The deformity involves fullness of the face, deviation of the chin toward the affected side, an elongated mandible, and flatness of the face on the unaffected side. (The side on which the ramus is short causes muscles to appear fuller; the muscles on the unaffected side are stretched so that side appears flatter.) Mandibular deviation causes malocclusion.

Diagnosis is based on a history of progressive facial asymmetry during the growth period and x-ray evidence of condylar deformity and antegonial notching (a depression in the inferior border of the mandible just anterior to the angle of the mandible). There is frequently a causative history.

Treatment consists of surgical shortening of the unaffected side of the mandible or lengthening of the affected side. Presurgical orthodontic therapy helps optimize results.

Temporomandibular joint cyst and tumors are very uncommon but show symptoms similar to intra-articular disorders that make up most of these disorders. The complaints are mostly pain, malocclusion and swelling. The most common TMJ-specific benign tumors are osteoma, synovial cyst, ganglion cyst etc. The treatment of these cyst and tumors may be conservative or radical surgery depending on nature of pathology.

TMJ surgery should only be considered after all other treatment options have been tried and severe pain remains. While TMJ surgery is the best option for many people, it’s important to weigh your options and make an informed decision.

Surgical intervention is appropriate only when:

1. There is identifiable pathology amenable to surgical intervention.
2. There is resultant loss of mechanical function
3. There is pain related to joint pathology
4. Any of the above has failed to respond to non-interventional treatment and there is, as a result, persistent loss of enjoyment of normal mandibular function which is negatively affecting the patient’s well-being in a persistent and unremitting manner.
5. There has been a thorough explanation of the relative pros and cons of a specific intervention, a review of the potential benefits, risks and complications.

1. A complete review of the nature of the TMD and all treatment attempts to date
2. Radiographic assessment including any or all of the following: dental panoramic radiograph, CT scan, MRI, bone scan.
3. A thorough medical assessment to include medical risk factors that may affect the surgical outcome.

1. Internal Derangements (disc displacement disorders)
2. Non-Inflammatory (non-infective degenerative disorders; post traumatic degeneration)
3. Inflammatory Disease (osteomyelitis, synovitis, Lupus, psoriasis, Rheumatoid Arthritis)
4. Neoplasia
5. Ankylosis

• Your TMJ symptoms aren’t that severe. For example, you may not need surgery if your jaw makes a clicking or popping sound when you open it, but there’s no pain associated with it.
• Your symptoms aren’t consistent. You may have severe, painful symptoms one day that vanish the next. This may be a result of certain repetitive motions or overuse — such as talking more than usual on a given day, chewing a lot of tough food, or constant gum chewing — that caused fatigue in your TMJ. In this case, your healthcare provider may recommend that you rest your jaw for a few hours or days.
• You can open and close your jaw all the way. Even if you have some pain or tenderness when you open and close your mouth, your doctor may not recommend surgery because of the risks involved. They may instead suggest medication, physical therapy, or lifestyle changes to reduce symptoms.
• It’s important to be evaluated by a oral and maxillofacial surgeon who’s trained in TMD. They will perform a thorough examination of your symptomatic history, clinical presentation, and radiological findings to determine if surgery will be beneficial for your symptoms. Surgery is considered a last resort if nonsurgical alternatives are unsuccessful.