Temporomandibular disorders (TMDs) are a group of more than 30 conditions that cause pain and dysfunction in the jaw joint and muscles that control jaw movement. “TMDs” refers to the disorders, and “TMJ” refers only to the temporomandibular joint itself. People have two TMJs; one on each side of the jaw. You can feel them by placing your fingers in front of your ears and opening your mouth.

There are three main classes of TMDs:

1. Disorders of the joints, including disc disorders.
2. Disorders of the muscles used for chewing (masticatory muscles).
3. Headaches associated with a TMD.

There are several disorders within each class. See diagram below for some examples.

Classification of Temporomandibular Disorders (TMDs) with Examples

Many TMDs last only a short time and go away on their own. However, in some cases they can become chronic, or long lasting. In addition, TMDs can occur alone or at the same time as other medical conditions such as headaches, back pain, sleep problems, fibromyalgia, and irritable bowel syndrome.

A recent study found that about 11-12 million adults in the United States had pain in the region of the temporomandibular joint.

Temporomandibular disorders are twice as common in women than in men, especially in women between 35 and 44 years old.

The temporomandibular joint (TMJ) is the joint that allows for opening (mandibular depression) and closing (mandibular elevation) of the mouth, as well as side-to-side and protraction/retraction motions of the lower jaw. This joint involves the articulation between the mandibular fossa and articular tubercle of the temporal bone, with the condyle (head) of the mandible. Located between these bony structures, filling the gap between the skull and mandible, is a flexible articular disc (Figure). This disc serves to smooth the movements between the temporal bone and mandibular condyle.

Movement at the TMJ during opening and closing of the mouth involves both gliding and hinge motions of the mandible. With the mouth closed, the mandibular condyle and articular disc are located within the mandibular fossa of the temporal bone. During opening of the mouth, the mandible hinges downward and at the same time is pulled anteriorly, causing both the condyle and the articular disc to glide forward from the mandibular fossa onto the downward projecting articular tubercle. The net result is a forward and downward motion of the condyle and mandibular depression. The temporomandibular joint is supported by an extrinsic ligament that anchors the mandible to the skull. This ligament spans the distance between the base of the skull and the lingula on the medial side of the mandibular ramus.

Dislocation of the TMJ may occur when opening the mouth too wide (such as when taking a large bite) or following a blow to the jaw, resulting in the mandibular condyle moving beyond (anterior to) the articular tubercle. In this case, the individual would not be able to close his or her mouth. Temporomandibular joint disorder is a painful condition that may arise due to arthritis, wearing of the articular cartilage covering the bony surfaces of the joint, muscle fatigue from overuse or grinding of the teeth, damage to the articular disc within the joint, or jaw injury. Temporomandibular joint disorders can also cause headache, difficulty chewing, or even the inability to move the jaw (lock jaw). Pharmacologic agents for pain or other therapies, including bite guards, are used as treatments.

The temporomandibular joint (TMJ) connects your jaw to the side of your head. When it works well, it enables you to talk, chew, and yawn. For people with TMJ dysfunction, problems with the joint and muscles around it may cause

• Pain that travels through the face, jaw, or neck
• Stiff jaw muscles
• Limited movement or locking of the jaw
• Painful clicking or popping in the jaw
• A change in the way the upper and lower teeth fit together

Jaw pain may go away with little or no treatment. Treatment may include simple things you can do yourself, such as eating soft foods or applying ice packs. It may also include pain medicines or devices to insert in your mouth. In very rare cases, you might need surgery.

Your jaw works hard every day so you can laugh, talk, smile, and eat. When it’s working properly, you may not give it much thought. But if your jaw starts to hurt, it can take the joy out of simple, everyday things.

The jaw joint is one of the most complex joints in the human body. For most people, it moves effortlessly up and down, side to side, and in and out, transitioning from one movement to the next seamlessly. But, more than 10 million people in the U.S. live with jaw pain and dysfunction.

Doctors call these conditions temporo-mandibular disorders. They’re more commonly called temporomandibular joint (TMJ) disorders.

“Temporomandibular disorders—and how people respond to them—vary widely,” explains Dr. Dena Fischer, a dental health expert at NIH. “For example, some experience discomfort, others tension, and still others severe pain.”

Some people get symptoms in the muscles that move the jaw. For others, it’s in a disc within the jaw joint that’s damaged. You can also develop arthritis, or joint inflammation . You can even have more than one kind of disorder at the same time.

TMJ disorders sometimes start after an injury. But for most people, there’s no obvious cause. In addition to pain, other symptoms can include stiffness, limited jaw movement, painful clicking or popping in the joint, or changes in the way the teeth fit together.

If you have any of these symptoms, talk with your health care provider. To diagnose a TMJ disorder, they’ll ask you questions about your symptoms and examine your head, neck, face, and jaw. They’ll also check your dental and medical history. They may use imaging tests, like X-rays, too.

Experts recommend starting with simple, self-care practices for jaw pain (see the Wise Choices box for tips). “For a lot of people, the pain will resolve over time,” Fischer explains. “Your doctor may also recommend trying a bite guard. These are plastic splints that fit over the teeth.”

Sometimes, TMJ disorders can become chronic—causing pain or discomfort that lasts more than three months. Aggressive treatments include surgery, splints that change the bite, and even adjusting or removing teeth. But whether these treatments help hasn’t been scientifically studied, explains Fischer.

For some people, they may make things worse. “And once you have surgery, you can’t put things back the way they were before,” she says.

If you have symptoms that last more than three months, your dentist or health care provider may refer you to a specialist. Doctors who specialize in muscles and bones, arthritis, pain, and the nervous system may be able to help.

But better treatments are needed. NIH-funded researchers have been studying the role that genes play in who develops a TMJ disorder and how long it lasts. In a large study, researchers identified several genes that are more common in people who have severe jaw pain. They’re now testing whether early treatment can help people with certain genes lower their risk of developing a chronic disorder.

“We hope that having a better understanding of why temporomandibular disorders develop will ultimately help us prevent them and find new treatments,” Fischer says.

Note: The title of this article was changed after publication.

Tackling Jaw Pain

Simple, self-care practices to try:

• Avoid hard foods.
• Use ice packs on the joint.
• Try over-the-counter pain medications, like ibuprofen, for a short amount of time.
• Avoid extreme movements, like wide yawning and chewing gum.
• Learn relaxation and stress reduction techniques.

Injury to the jaw or temporomandibular joint can lead to some TMDs, but in most cases, the exact cause is not clear. For many people, symptoms seem to start without obvious reason. Recent research suggests a combination of genes, psychological and life stressors, and how someone perceives pain, may play a part in why a TMD starts and whether it will be long lasting.

Because TMDs are more common in women than in men, researchers are exploring whether the differences in TMJ structure and mechanics between females and males may play a role.

Research does not support the belief that a bad bite or orthodontic braces cause TMDs.

It is important to know that sounds (such as clicking or popping) without pain in the TMJs are common, are considered normal, and don’t need treatment.

However, the following symptoms may signal a TMD:

• Pain in the chewing muscles and/or jaw joint (most common symptom).
• Pain that spreads to the face or neck.
• Jaw stiffness.
• Limited movement or locking of the jaw.
• Painful clicking, popping, or grating in the jaw joint when opening or closing the mouth.
• Ringing in the ears, hearing loss, or dizziness.
• A change in the way the upper and lower teeth fit together.

There is no widely accepted, standard test available to diagnose TMDs. Because the exact causes and symptoms are not clear, identifying these disorders can be difficult.

Your doctor or dentist will note your symptoms and take a detailed medical history. He or she will ask questions about your pain, including its location, when it occurs, what makes it better or worse, and if it stays in one area or spreads to other parts of your body. The doctor or dentist will also ask if you have other pain conditions such as headache or back pain.

He or she also will examine your head, neck, face, and jaw for tenderness; jaw clicking or popping; or difficulty with movement. The doctor or dentist might also suggest imaging studies such as an x-ray, magnetic resonance imaging (MRI), or computed tomography (CT).

Pain in the mouth, jaw, or face may or may not be related to TMDs. Your doctor or dentist may have to rule out other conditions before diagnosing a TMD.

Before receiving treatment for TMDs, you should know:

• Sounds without pain in the temporomandibular joints are normal, happen frequently, and do not need treatment.
• Signs and symptoms of TMD go away in many people without treatment.
• Because evidence is lacking for the majority of TMD treatments, experts strongly recommend staying away from treatments that cause permanent changes to the jaw joints, teeth, or bite; or that involve surgery.

Nonsurgical Treatments

Because many jaw joint and muscle problems are temporary and do not get worse, simple treatment may be all that is necessary.

When you first feel discomfort in your jaw joints or muscles, your doctor or dentist may have you:

• Eat soft foods.
• Apply heat or cold to the face in combination with exercises to gently stretch and strengthen the jaw muscles.
• Take over-the-counter medications, for example nonsteroidal anti-inflammatory drugs (NSAIDs), like ibuprofen.
• Reduce habits such as jaw clenching, gum chewing, or nail biting.

If these steps do not help, or if in the process of trying them your doctor/dentist diagnoses a specific type of TMD, one or more of the following treatments may be recommended.

Physical Therapy

The goal of physical therapy is to maintain, improve, or bring back movement and physical function. There are several types of physical therapy. One type is manual therapy, in which a therapist uses his/her hands to stretch the soft tissues and muscles around the joint. Manual therapy has been shown to help improve function and relieve pain.

Self-management and Behavioral Health Approaches

Self-management refers to activities you can do yourself and include:

• Learn all you can about your specific type(s) of TMD.
• Learn meditation & relaxation techniques.
• Set specific goals related to managing your condition.
• Stay involved in activities that are meaningful to you.

Certain behavioral health approaches, usually offered by a psychologist, have been shown to help manage TMDs. These include cognitive behavioral therapy and biofeedback.

Cognitive behavioral therapy seeks to identify negative thoughts or thought patterns and change them, as well as provide coping skills.

Biofeedback involves using sensors that monitor breathing, heart rate, muscle contraction, and temperature. For example, a sensor on your jaw can detect when you tighten your jaw muscles. With the help of a therapist, you can learn to notice the unwanted behavior and relax.

Medications

Your doctor or dentist may recommend medication(s) to treat your symptoms.

These include:

• Over-the-counter medications such as:
  • nonsteroidal anti-inflammatory drugs (NSAIDs), used to treat pain
• Prescription medications such as:
  • Antianxiety medications
  • Antidepressants
  • Antiseizure medications
  • Opioids

Some of these medications can lead to addiction or have other serious side effects. If you are prescribed any of these medications, make sure your doctor or dentist explains how to take them and for how long.

Intraoral Appliances

Intraoral appliances are devices that fit over the teeth. They do not change the teeth or bite. They are also known as nightguards, splints, stabilization appliances, occlusal splints, interocclusal splints, repositioning splints, or bruxism splints.

There is not a lot of evidence they improve TMD pain. If a dentist or doctor suggests you use one:

• Make sure it is not designed to permanently change your bite.
• Stop using it and consult your dentist/doctor if it causes pain.

Complementary Treatments

A complementary treatment is a non-mainstream practice used together with conventional medicine. Acupuncture and transcutaneous electrical nerve stimulation (TENS) are two complementary treatments that have been studied for TMDs.

Acupuncture is a technique in which practitioners stimulate specific points on the body—most often by inserting thin needles through the skin. There is limited evidence that it helps TMDs.

TENS is a battery-powered device that uses electrodes placed on the skin. The device creates electrical impulses that may change how pain is perceived. Although some studies have shown that TENS may help relieve pain in TMDs and improve the ability to open the mouth, the studies were small with short-duration TENS treatments.

Surgery and Other Medical & Dental Procedures

The treatments discussed in this section are more complex, involve going into the chewing muscles or the temporomandibular joints (with a needle or other instrument), or changing your bite and teeth. More importantly, some of them – like occlusal treatments (see below)— don’t work and may make the problem worse. Before having any of these procedures:

• Ask about simpler treatments and try those first.
• Ask the doctor or dentist to explain the procedure—in detail—in a way you can understand.
• Ask how the procedure will help improve your specific TMD.
• Ask about the risks.
• Get second opinions from qualified medical or dental specialists.

Occlusal Treatments

Occlusion refers to how teeth fit together. For years it was thought that misaligned teeth (malocclusion) were a cause of TMDs; however, there is no evidence to support this belief. Occlusal treatments modify the teeth and bite. Examples include:

• Placing crowns on the teeth.
• Grinding down the teeth.
• Using orthodontic treatment(s) to change the position of some or all teeth.

There is no evidence these occlusal treatments work, and they could make the problem worse.

Botulinum Toxin

Botulinum toxin Type A works by relaxing muscles. It is FDA-approved for some medical conditions (like migraines) but not for TMDs. Studies have looked at injecting botulinum toxin Type A into the chewing muscles to reduce muscle spasm and pain. However, the information from these studies is limited and it is not clear whether this medication works to relieve TMD symptoms.

Prolotherapy

Prolotherapy involves injecting a solution into the TMJ area that causes irritation, with the goal of triggering the body to respond by repairing the joint. Prolotherapy has shown promise specifically for TMDs in which the joint is out of its normal position (dislocation) or when the joint goes beyond its normal range of movement (hypermobility). However, there have been only a few small studies on this treatment for TMDs.

Arthrocentesis

In this procedure a needle is used to push liquid into the TMJ. The pressure caused by the liquid removes scar-like tissue (adhesions). In addition, when the liquid is flushed out of the joint, it removes substances that cause inflammation. Arthrocentesis has been shown to help with pain relief and improve mouth opening in people whose temporomandibular disc is out of place; however, these effects do not last long.

Arthroscopy

During arthroscopy the doctor inserts an instrument with a tiny video camera into the jaw joint. The doctor can see the joint, which can help in diagnosis. He or she can also remove adhesions or reposition the joint’s disc. This procedure works moderately well in helping improve pain and function.

Surgery

Open surgery gives access to the temporomandibular joint through a cut (incision) next to the ear. It’s important to know that surgery makes permanent changes to your joint. There are no long-term research studies on the safety of open surgery for TMDs or on how well it works to relieve symptoms.

Surgery should only be considered if:

• There is destruction of the joint that cannot be fixed with other procedures.
• There are severe symptoms (pain and/or difficulty opening the mouth), despite trying other treatments.

If your healthcare provider suggests surgery, be sure to ask:

• Why are you suggesting surgery?
• Are there other options besides surgery?
• How will it help me?
• What are the risks?

TMJ Implants

Implants are artificial devices that are used to replace part of the jaw joint or the entire joint. There are currently three TMJ implants approved by the FDA.

Implants might be considered when:

• There is an injury to the joint.
• There is a condition you’re born with (congenital condition) that needs to be repaired.
• The joint is frozen (ankylosis), commonly caused by injury or infection.
• There’s severe damage to the joint.
• There’s ongoing pain.
• All simpler treatments have been tried and have failed.

Some studies suggest that, when used in very specific cases, TMJ implants can improve function and quality of life. As with any surgery, proceed with caution.

Implants used many years ago (and since taken off the market), did not help patients and left them with severe complications, including permanent damage to the jaw joint(s). Because of this, researchers have called for long-term studies to look at the safety and efficacy of the newer TMJ implants.

Remember: Before any surgery, including implant surgery, it is extremely important to get opinions from more than one doctor and to completely understand the risks. If possible, seek an opinion from a surgeon who specializes in treating TMDs.

Summary of Treatments for Temporomandibular Disorders (TMDs)

Temporomandibular joint (TMJ) implants are intended to be surgically implanted in the jaw to replace the temporomandibular joint. A variety of artificial materials have been used to partially or totally replace the TMJ, including plastics, Teflon, silicone, metals, and a combination of these materials.

About TMJ Implants

The TMJ implant may take many different forms. Some implants are intended to replace only a part of the joint, such as the temporomandibular joint disc or the glenoid fossa, and other implants are intended to replace the entire joint.

The purpose of these types of implants is to restore the TMJ function, including opening and closing the mouth and chewing. However, all movements of a normal joint may not be possible with an artificial joint.

Candidates for TMJ Implants

TMJ implants are intended for patients who do not respond to other forms of treatment, including non-surgical treatment, or for whom prior joint reconstruction, including tissue grafts and/or joint replacement, failed to restore function and relieve symptoms. The National Institute of Dental and Craniofacial Research (NIDCR) says, "less is often best in treating TMJ disorders." Discuss all treatment options with your healthcare provider.

Candidates for TMJ implants include:

• Patients who have undergone non-surgical treatments and at least one previous surgical procedure.
• Patients whose previous surgeries may have resulted in failed joint reconstruction. This includes patients who have undergone bone graft procedures using bone grafts derived from their patient's own bone tissue or from synthetic bone. Often these patients may also have experienced numerous surgeries to one or both of their temporomandibular joints.
• Patients who have had inflammatory or immunological responses, including end-stage TMJ deterioration, which may preclude further reconstruction with bone from the patient.
• Patients with severe pain and extremely limited function, including patients with severe trauma to the temporomandibular joint, neoplasms (tumors), congenital deformities, ankylosis, or arthritis involving the TMJ, rendering the joint dysfunctional.

Problems Reported with TMJ Implants

As with all medical devices, the FDA receives medical device reports (MDRs) related to problems or concerns with TMJ implants. Approximately 5,500 TMJ total joint replacement procedures were performed in U.S. from 2005 to 2014 (Journal of Oral and Maxillofacial Surgery, Volume 74, Issue 8, 1531 – 1538). The FDA received 680 MDRs related to TMJ implants from 2014-2018, prompting increased engagement with patients living with this condition, evaluation of patient-reported outcome measures, and review of postmarket studies.

The most frequent patient problems reported in MDRs include pain, swelling, infection, headache, limited movement of the implanted joint, excessive bone growth, increased sensitivity, disability, and the need for additional surgical procedures (including revision) and non-surgical treatments or therapy.

Recommendations for Patients

The FDA provides these recommendations for patients considering TMJ implants and for patients who have already received implants.

Find a health care provider who is knowledgeable about temporomandibular disorder (TMD) symptoms and treatment options. When choosing a health care provider, you may wish to consider their training, experience, board certification, their patient follow-up, and your own comfort level.

Notify the FDA if you are having problems with your TMJ implant. If you are having problems with your TMJ implant, refer to Reporting TMD Device Problems to the FDA.

Make sure that you can receive notifications about any problems with your TMJ implants. Notifications may come from the manufacturer to you or to your health care provider. Accordingly, be sure to contact the doctor who performed your TMJ implant surgery or the manufacturer of your implant if you have a change in contact information (such as address or phone number).

You may also proactively monitor the manufacturer’s website and social media as well as www.FDA.gov. The best way to stay informed about medical device recalls is to subscribe to the Medical Device Safety and Recalls email list.

If you receive a safety notification for your TMJ implants or notice of a recall (removal or correction) from the manufacturer or the FDA, please contact your physician to discuss how this may impact your medical care.

If you think you have a TMD or are diagnosed with one:

• Start with simple treatments first; remember that TMD symptoms often go away on their own, without treatment.
• Consult a dentist or doctor.
• Learn all you can about the TMD you have.
• Avoid (when possible) treatments that involve going into or permanently changing the jaw joints, especially surgery or TMJ implants.
• Understand all the risks when considering surgery or other medical or dental procedures that result in permanent change and seek an opinion from an orofacial pain clinic at a medical or dental school, if possible.