Arthritis and arthrosis of the temporomandibular joint (TMJ): classification, clinical course, diagnosis, treatment, complications and prevention. TMJ syndrome pain. Surgical TMJ arthroscopy. Tummy aches and its components.
TMJ Anatomy
The temporomandibular joint, or TMJ, is the articulation between the condyle of the mandible and the squamous portion of the temporal bone.
The condyle is elliptically shaped with its long axis oriented mediolaterally.
The articular surface of the temporal bone is composed of the concave articular fossa and the convex articular eminence.
The MENISCUS is a fibrous, saddle shaped structure that separates the condyle and the temporal bone. The meniscus varies in thickness: the thinner, central intermediate zone separates thicker portions called the anterior band and the posterior band. Posteriorly, the meniscus is contiguous with the posterior attachment tissues called the bilaminar zone. The bilaminar zone is a vascular, innervated tissue that plays an important role in allowing the condyle to move foreward. The meniscus and its attachments divide the joint into superior and inferior spaces. The superior joint space is bounded above by the articular fossa and the articular eminence. The inferior joint space is bounded below by the condyle. Both joint spaces have small capacities, generally 1cc or less.
Normal TMJ Function
When the mouth opens, two distinct motions occur at the joint. The first motion is rotation around a horizontal axis through the condylar heads. The second motion is translation. The condyle and meniscus move together anteriorly beneath the articular eminence. In the closed mouth position, the thick posterior band of the meniscus lies immediately above the condyle. As the condyle translates forward, the thinner intermediate zone of the meniscus becomes the articulating surface between the condyle and the articular eminence. When the mouth is fully open, the condyle may lie beneath the anterior band of the meniscus.
QuickTime movie of Normal TMJ motion (37K)
TMJ Dysfunction
Internal derangement of the TMJ is present when the posterior band of the meniscus is anteriorly displaced in front of the condyle. As the meniscus translates anteriorly, the posterior band remains in front of the condyle and the bilaminar zone becomes abnormally stretched and attenuated. Often the displaced posterior band will return to its normal position when the condyle reaches a certain point. This is termed anterior displacement with reduction.
When the meniscus reduces the patient often feels a pop or click in the joint. In some patients the meniscus remains anteriorly displaced at full mouth opening. This is termed anterior displacement without reduction. Patients with anterior displacement without reduction often cannot fully open their mouths’. Sometimes there is a tear or perforation of the meniscus. Grinding noises in the joint are often present.
Temporomandibular joint disorders are problems which affect the jaw joint.
The jaw joint is located just in front of the ear canal, and it joins the jaw bone (mandible) to the skull near to the temple. The jaw joint is also called the temporomandibular joint (TMJ). Problems affecting this joint are usually known as TMJ disorders. However, there are various other medical terms for for this condition – for example, TMJ dysfunction, TMJ pain and myofascial pain disorder.
Understanding the jaw joint
A joint is where two bones meet. Joints allow movement and flexibility between two bones. The jaw joint allows movement between the jawbone (mandible) and the skull. Muscles attached to the skull and jawbone cause the jawbone to move as the mouth is opened and closed.
Inside the jaw joint, there is a smooth material called cartilage, covering part of the bones. There is also a cartilage disc within the joint. The joint is lubricated by fluid called synovial fluid.
What are the symptoms of temporomandibular joint disorders?
Pain in the joint area or nearby. The pain is usually located just in front of the ear, and it may spread to the cheek, the ear itself, and to the temple.
Jaw movements may be reduced. This may be a general tight feeling or a sensation of the jaw getting stuck. Very rarely, the jaw may get ‘locked’, causing difficulty in opening or closing the mouth.
Clicks or noises can sometimes be heard coming from the jaw joint when you chew or move your mouth. These noises can be normal, so they are only relevant if you have other symptoms in the joint, such as pain or reduced movement.
Because the ear is very close to the jaw joint, some people get ear symptoms such as noise in the ear, sensitivity to sound or dizziness (vertigo).
How common are temporomandibular joint disorders?
They are fairly common. About 1 in 10 people have symptoms in the jaw joint at some time in their lives. Of these people, only about 1 in 20 consult a doctor for this problem.
What causes temporomandibular joint disorders?
In general, TMJ disorders are thought to have a ‘multifactorial‘ cause, meaning that there are usually a number of factors contributing to the cause. These factors can be grouped into two types: problems linked to the muscles working the joint, and problems inside the joint itself. The muscle problems are the most common type, particularly for younger people.
Problems with the muscles may be caused by:
Overactivity of the jaw muscles. This can occur if you clench your jaw a lot during sleep, which is quite common. Rarely, other conditions make the jaw muscles overactive. For example, there are some rare kinds of movement disorders (called orofacial dystonias) which cause excessive jaw clenching.
Increased sensitivity to pain. We don’t know why this happens, but it may be linked to stress, or to some other process which affects pain sensitivity. Some doctors call this type of problem a pain syndrome because the exact cause of the pain is not known.
Problems in the joint may be caused by:
Wear and tear to the inside of the joint – for example, wear and tear to the cartilage. Sometimes this is due to a type of arthritis called osteoarthritis. This problem tends to affect older rather than younger people.
Certain types of arthritis. Arthritis means inflammation in a joint. There are different kinds of arthritis. For example, rheumatoid arthritis and gout are both types of arthritis which may affect various joints in the body, and they can sometimes affect the jaw joint.
Injury to the TMJ or to its cartilage disc can cause TMJ pain.
How are temporomandibular joint disorders diagnosed?
Often, the diagnosis is made on the basis of your symptoms and a doctor’s examination. In many cases, no tests are necessary if you are healthy and have symptoms that are typical of a TMJ disorder. Possible tests are:
Blood tests which may be helpful to look for signs of inflammation, or to rule out other causes of pain in that area.
An MRI scan which can be used to give a detailed picture of the joint. X-rays are another option, but are used less ofteow that MRI scans are available.
A diagnostic nerve block which may help to clarify whether the pain is coming from the joint or the muscles. Local anaesthetic is injected near the nerve which goes to the jaw joint. If this relieves the pain, then it suggests that the pain comes from the joint itself.
Arthroscopy (using a fibre-optic device to look inside the joint) which may be used if other tests do not show the cause of the pain.
What is the treatment for temporomandibular joint disorders?
Most problems in the jaw joint can be helped with simple treatments such as painkillers and advice on how to rest the joint. There are various treatments which are often used in combination:
Resting the jaw joint
You can rest the joint by eating soft food and not using chewing gum. Also, avoid opening the mouth very wide – so don’t do too much singing, and try not to yawn too widely. Massaging the muscles and applying warmth can help.
Other treatments are relaxation and stress-reducing therapies – presumably because people tend to clench their jaw when they are stressed, or because stress makes pain worse.
Splints or bite guards are sometimes suggested. These cover the teeth at night to reduce clenching of the jaw, and can be made by dentists. There is no definite evidence from research trials that they work, but some people find them helpful.
Medication
Painkillers such as paracetamol, ibuprofen or codeine can help. If these are not enough, muscle relaxants or a small dose of a medicine called a tricyclic antidepressant can give added pain relief.
Physiotherapy
Physiotherapy treatments, such as ultrasound and gentle jaw exercises, can be helpful.
Treatment of other conditions
If there is an underlying condition – for example, a type of arthritis which is contributing to the TMJ disorder – this may need treating in its own right.
Injections or surgery
An injection of a medicine called a steroid into the joint may help, when symptoms are due to inflammation in the joint.
If the jaw muscles are overactive to a severe degree (such as with a movement disorder), an injection of botulinum toxin can reduce symptoms. There is debate about how effective this treatment is.
Arthroscopy (this involves inserting a fibre-optic device inside the joint) can be used for some types of treatment or surgery to the joint.
For a very few patients, surgical repair of the joint may be suggested. Various operations can be done, depending on the individual situation.
Current discussions
What is the outlook for temporomandibular joint disorders?
Generally the outlook is good. Most TMJ disorders improve over time and do not get worse. It is very rare to get any complications with this condition. Some people do have symptoms that last longer or come back (recur), but even these can usually be improved with the treatments described above. Most people do not need injections or surgery and will get better with simple treatments and time.
TMJ Anatomy
The temporomandibular joint (TMJ) or jaw joint is a bi-arthroidal hinge joint that allows the complex movements necessary for eating, swallowing, talking and yawning. Dysfunction of the TMJ can cause severe pain and lifestyle limitation. Temporomandibular disorders are common and sufferers will often seek physiotherapeutic advice and treatment. Good knowledge of the anatomy of the TMJ and related structures is essential to correct diagnosis and appropriate treatment.
Joint
Capsule – The capsule is a fibrous membrane that surrounds the joint and attaches to the articular eminence, the articular disc and the neck of the mandibular condyle.
Articular disc – The articular disc is a fibrous extension of the capsule that runs between the two articular surfaces of the temporomandibular joint. The disc articulates with the mandibular fossa of the temporal bone above and the condyle of the mandible below. The disc divides the joint into two sections, each with its own synovial membrane. The disc is also attached to the condyle medially and laterally by the collateral ligaments. The anterior disc attaches to the joint capsule and the superior head of the lateral pterygoid. The posterior portion attaches to the mandibular fossa and is referred to as the retrodiscal tissue.
Retrodiscal tissue – Unlike the disc itself, the retrodiscal tissue is vascular and highly innervated. As a result, the retrodiscal tissue is often a major contributor to the pain of Temporomandibular Disorder (TMD), particularly when there is inflammation or compression within the joint
Ligaments
The ligaments give passive stability to the TMJ.
The temporomandibular ligament is the thickened lateral portion of the capsule, and it has two parts, an outer oblique portion and an inner horizontal portion.
The stylomandibular ligament runs from the styloid process to the angle of the mandible. The sphenomandibular ligament runs from the spine of the sphenoid bone to the lingula of mandible.
The oto-mandibular ligaments are the discomalleolar ligament (DML), which arises from the malleus (one of the ossicles of the middle ear) and runs to the medial retrodiscal tissue of the TMJ, and the anterior malleolar ligament (AML), which arises from the malleus and connects with the lingula of the mandible via the sphenomandibular ligament. The oto-mandibular ligaments may be implicated in tinnitus associated with TMD. A positive correlation has been found between tinnitus and ipsilateral TMJ disorder. It has been proposed that a TMJ disorder may stretch the DML and AML, thereby affecting middle ear structure equilibrium. “It thus seems that otic symptoms (tinnitus, otalgia (ear pain), dizziness and hypoacusis) corresponding to altered ossicular spatial relationships (such as conductive middle ear pathologies) can also be produced from masticatory system pathologies.”
Muscles and Jaw Movement
The jaw can move forward and back, side to side and can open and close. Each of these movements are performed by a number of muscles working together to perform the movement while controlling the position of the condyle within the mandibular fossa. Chewing and talking require a combination of jaw movements in a number of directions[12][13].
Opening – inferior head of lateral pterygoid, anterior digastric, mylohyoid. Opening is also controlled by eccentric contraction of the closing muscles against gravity. Opening is a complex movement consisting of an early rotary component in the first 2-3cms of movement with a forward glide towards the end of range. The articular disc moves forward with the condyle as it glides forward, effectively extending the superior articular surface of the mandibular fossa.
Closing – masseter, anterior and middle temporalis, medial pterygoid, superior head lateral pterygoid.
Protrusion – bilateral contraction of the lateral pterygoid.
Retrusion – middle and posterior temporalis, possibly helped by deep posterior portion of masseter
Laterotrusion (side to side) – ipsilateral middle and posterior temporalis, contralateral inferior head lateral pterygoid.
Temporomandibular disorders (TMD) occur as a result of problems with the jaw, jaw joint and surrounding facial muscles that control chewing and moving the jaw. These disorders are often incorrectly called TMJ, which stands for temporomandibular joint.
What Is the Temporomandibular Joint (TMJ)?
The temporomandibular joint (TMJ) is the hinge joint that connects the lower jaw (mandible) to the temporal bone of the skull, which is immediately in front of the ear on each side of your head. The joints are flexible, allowing the jaw to move smoothly up and down and side to side and enabling you to talk, chew, and yawn. Muscles attached to and surrounding the jaw joint control the position and movement of the jaw.
What Causes TMD?
The cause of TMD is not clear, but dentists believe that symptoms arise from problems with the muscles of the jaw or with the parts of the joint itself.
Injury to the jaw, temporomandibular joint, or muscles of the head and neck – such as from a heavy blow or whiplash – can cause TMD. Other possible causes include:
Grinding or clenching the teeth, which puts a lot of pressure on the TMJ
Dislocation of the soft cushion or disc between the ball and socket
Presence of osteoarthritis or rheumatoid arthritis in the TMJ
Stress, which can cause a person to tighten facial and jaw muscles or clench the teeth
What Are the Symptoms of TMD?
People with TMD can experience severe pain and discomfort that can be temporary or last for many years. More women than men experience TMD, and TMD is seen most commonly in people between the ages of 20 and 40.
Common symptoms of TMD include:
Pain or tenderness in the face, jaw joint area, neck and shoulders, and in or around the ear when you chew, speak, or open your mouth wide
Limited ability to open the mouth very wide
Jaws that get “stuck” or “lock” in the open- or closed-mouth position
Clicking, popping, or grating sounds in the jaw joint when opening or closing the mouth (which may or may not be accompanied by pain) or chewing
A tired feeling in the face
Difficulty chewing or a sudden uncomfortable bite – as if the upper and lower teeth are not fitting together properly
Swelling on the side of the face
May occur on one or both sides of the face
Other common symptoms of TMD include toothaches, headaches, neck aches, dizziness, earaches, hearing problems, upper shoulder pain, and ringing in the ears (tinnitis).
How Is TMD Diagnosed?
Because many other conditions can cause similar symptoms to TMD – including a toothache, sinus problems, arthritis, or gum disease – your dentist will conduct a careful patient history and physical examination to determine the cause of your symptoms.
Your dentist will examine your temporomandibular joints for pain or tenderness; listen for clicking, popping, or grating sounds during jaw movement; look for limited motion or locking of the jaw while opening or closing the mouth; and examine bite and facial muscle function. Sometimes panoramic X-rays will be taken. These full face X-rays allow your dentist to view the entire jaws, temporomandibular joint, and teeth to make sure other problems aren’t causing the TMD symptoms. Sometimes, other imaging tests, such as magnetic resonance imaging (MRI) or a computer tomography (CT), are needed. The MRI views the soft tissue such as the TMJ disc to see if it is in the proper position as the jaw moves.
scan helps view the bony detail of the joint.
Your dentist may decide to send you to an oral surgeon (also called an oral and maxillofacial surgeon) for further care and treatment. This oral health care professional specializes in surgical procedures in and about the entire face, mouth, and jaw area.
What Treatments Are Available for TMD?
Treatments for TMD range from simple self-care practices and conservative treatments to injections and surgery. Most experts agree that treatment should begin with conservative, nonsurgical therapies first, with surgery left as the last resort. Many of the treatments listed below often work best when used in combination.
Basic Treatments for TMD
Some basic, conservative treatments for TMD include:
Apply moist heat or cold packs. Apply an ice pack to the side of your face and temple area for about 10 minutes. Do a few simple stretching exercises for your jaw (as instructed by your dentist or physical therapist). After exercising, apply a warm towel or washcloth to the side of your face for about 5 minutes. Perform this routine a few times each day.
Eat soft foods. Eat soft foods such as yogurt, mashed potatoes, cottage cheese, soup, scrambled eggs, fish, cooked fruits and vegetables, beans, and grains. In addition, cut foods into small pieces to decrease the amount of chewing required. Avoid hard and crunchy foods (like hard rolls, pretzels, raw carrots), chewy foods (like caramels and taffy) and thick and large foods that require your mouth to open wide to fit.
Take medications. To relieve muscle pain and swelling, try nonsteroidal anti-inflammatory drugs (NSAIDs), such as naproxen or ibuprofen (Advil, Motrin, Aleve). Your dentist can prescribe higher doses of these or other drugs for pain relief. Muscle relaxants, especially for people who grind or clench their teeth, can help relax tight jaw muscles. Anti-anxiety medications can help relieve stress that is sometimes thought to aggravate TMD. Antidepressants, when used in low doses, can also help reduce or control pain. Muscle relaxants, anti-anxiety drugs, and antidepressants are available by prescription only.
Low-level laser therapy. This is used to reduce the pain and inflammation, as well as increase range of motion to the neck and in opening the mouth.
Wear a splint or night guard. Splints and night guards are plastic mouthpieces that fit over the upper and lower teeth. They prevent the upper and lower teeth from coming together, lessening the effects of clenching or grinding the teeth. They also correct the bite by positioning the teeth in their most correct and least traumatic position. The main difference between splints and night guards is that night guards are only worn at night and splints are worn all the time. Your dentist will discuss with you what type of mouth guard appliance you may need.
Undergo corrective dental treatments. Corrective treatments including replacing missing teeth and using crowns, bridges, or braces to balance the biting surfaces of your teeth or to correct a bite problem.
Avoid extreme jaw movements. Keep yawning and chewing (especially gum or ice) to a minimum and avoid extreme jaw movements such as yelling or singing.
Don’t rest your chin on your hand or hold the telephone between your shoulder and ear. Practice good posture to reduce neck and facial pain.
Keep your teeth slightly apart as often as you can to relieve pressure on the jaw. To control clenching or grinding during the day, place your tongue between your teeth.
Learning relaxation techniques to help control muscle tension in the jaw. Ask your dentist about the need for physical therapy or massage. Consider stress reduction therapy, including biofeedback.
More Controversial Treatments for TMD
When the basic treatments listed above prove unsuccessful, your dentist may suggest one or more of the following treatments for TMD:
Transcutaneous electrical nerve stimulation (TENS). This therapy uses low-level electrical currents to provide pain relief by relaxing the jaw joint and facial muscles. This treatment can be done at the dentist’s office or at home.
Ultrasound. Ultrasound treatment is deep heat that is applied to the TMJ to relieve soreness or improve mobility.
Trigger-point injections. Pain medication or anesthesia is injected into tender facial muscles called “trigger points” to relieve pain.
Radio wave therapy. Radio waves create a low level electrical stimulation to the joint, which increases blood flow. The patient experiences relief of pain in the joint.
Surgery for TMD
Surgery for TMD should only be considered after all other treatment options have been unsuccessful. Because surgery is irreversible, it is wise to get a second or even third opinion from other dentists.
There are three types of surgery for TMD: arthrocentesis, arthroscopy, and open-joint surgery. The type of surgery needed depends on the TMD problem.
Arthrocentesis. This is a minor procedure performed in the office under general anesthesia. It is performed for sudden-onset, closed lock cases (restricted jaw opening) in patients with no significant prior history of TMJ problems. The surgery involves inserting needles inside the affected joint and washing out the joint with sterile fluids. Occasionally, the procedure may involve inserting a blunt instrument inside of the joint. The instrument is used in a sweeping motion to remove tissue adhesion bands and to dislodge a disc that is stuck in front of the condyle (the part of your TMJ consisting of the “ball” portion of the “ball and socket”)
Arthroscopy. Patients undergoing arthroscopic surgery for TMD first are given general anesthesia. The surgeon then makes a small incision in front of the ear and inserts a small, thin instrument that contains a lens and light. This instrument is hooked up to a video screen, allowing the surgeon to examine the TMJ and surrounding area. Depending on the cause of the TMD, the surgeon may remove inflamed tissue or realign the disc or condyle.
Compared with open surgery, this surgery is less invasive, leaves less scarring, and is associated with minimal complications and a shorter recovery time. Depending on the cause of the TMD, arthroscopy may not be possible, and open-joint surgery may be necessary.
Open-joint surgery. Patients undergoing open-joint surgery also are first given general anesthesia. Unlike arthroscopy, the entire area around the TMJ is opened so that the surgeon can get a full view and better access. There are many types of open-joint surgeries. This treatment may be necessary if:
The bony structures that comprise the jaw joint are deteriorating
There are tumors in or around your TMJ
There is severe scarring or chips of bone in the joint
Compared with arthroscopy, open-joint surgery for TMD results in a longer healing time and there is a greater chance of scarring and nerve injury.
Arthritis (Temporomandibular Joint)
Several different kinds of arthritis can affect the temporomandibular joint (TMJ). The most common kind of arthritis, called osteoarthritis, causes degeneration of cartilage and bone at the joints and can occur at the TMJ. It can be brought on by severe trauma to the joint or can simply occur due age-related deterioration. Rheumatoid arthritis, a chronic inflammation of the joint can affect the TMJ in the same manner it affects other joints. Arthritic changes can also be caused by an infection in the joint. Arthritic joint damage tends to increase as the disease progresses. Ankylosis (fusion of the jaw joint) can occur in cases of severe rheumatoid arthritis.
Symptoms
Symptoms can vary depending on the type of arthritis, but can include painful swelling in the joint, limited range of movement of the jaw, and various joint sounds such as popping, clicking, scraping or grinding during opening and closing.
Diagnosis
Diagnosis involves examining the motion of the jaw and visualizing the structural integrity of the jaw joint using imaging techniques such as X-ray, CT or MRI scans, or arthroscopy. Arthrocentesis, the removal and analysis of fluid in the joint using a syringe, can also be helpful, and can determine if an infection is present.
Treatment
Often, pain and discomfort caused by arthritis can be relieved with treatments and self-care techniques similar to those used for other TMD’s and arthritic conditions. For example, treatment may involve eating a soft diet and applying moist heat packs to the painful area. Splints worn in the mouth can be effective in managing the symptoms. Non-steroidal anti-inflammatory drugs, physical therapy involving mild jaw exercises, and stress management may also be helpful in managing the condition.
Injection of steroids directly into the painful joint, an arthritis treatment used at other joints, may provide pain relief. However, steroid injections can only be done a limited number of times, as repeated use can harm the joint. Arthrocentesis, washing out of the inflamed joint fluid, may also help in some patients.
Surgery may be appropriate if the symptoms of the arthritic degeneration of bone and cartilage are not responsive to conservative and non-surgical care. Surgery cannot cure the disease, but may be able to ease the symptoms. Arthroscopic surgery, using tiny instruments and fiber optics to visualize the joint, is less invasive than open surgery, and is associated with less scarring and shorter recovery time. However, in some cases, open surgery may be more appropriate.
Arthritis of the Temporomandibular Joint (TMJ)
Infectious arthritis, traumatic arthritis, osteoarthritis, RA, and secondary degenerative arthritis can affect the temporomandibular joint (TMJ).
Infectious arthritis: Infection of the TMJ may result from direct extension of adjacent infection or hematogenous spread of bloodborne organisms (see Infections of Joints and Bones: Acute Infectious Arthritis). The 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. Parenteral penicillin G is the drug of choice until a specific bacteriologic diagnosis can be made on the basis of
culture and sensitivity testing. Suppurative infections are aspirated or incised. Once the infection is controlled, jaw-opening exercises help prevent scarring and limitation of motion.
Traumatic arthritis: Rarely, acute injury (eg, due to difficult tooth extraction or endotracheal intubation) may lead to arthritis of the TMJ. Pain, tenderness, and limitation of 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 NSAIDs, application of heat, a soft diet, and restriction of jaw movement.
Osteoarthritis: The TMJ may be affected, usually in people > 50 yr. Occasionally, patients complain of stiffness, grating, or mild pain. Crepitus results from a hole worn through the disk, causing bone to grate on bone. Joint involvement is generally bilateral. X-rays or CT may show flattening and lipping of the condyle, suggestive of dysfunctional change. Treatment is symptomatic. A mouth guard worn during the night or day may help alleviate pain and reduce grating sounds in patients with missing teeth (which can cause their jaws to come closer together when biting).
Rheumatoid arthritis: The TMJ is affected in > 17% of adults and children with RA, 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 later show bone destruction, which may result in an anterior open-bite deformity. 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 RA in other joints. In the acute stage, NSAIDs may be given, and jaw function should be restricted. A mouth guard or splint worn at night is often helpful. When symptoms subside, mild jaw exercises help prevent excessive loss of motion. Surgery is necessary if ankylosis develops but should not be done until the condition is quiescent.
Secondary degenerative arthritis: This type of arthritis usually develops in people aged 20 to 40 yr after trauma or in people with persistent myofascial pain syndrome (see Temporomandibular Disorders: 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. Diagnosis is based on x-rays, which generally show condylar flattening, lipping, spurring, or erosion. Unilateral joint involvement helps distinguish secondary degenerative arthritis from osteoarthritis.
Treatment is conservative, as it is for myofascial pain syndrome, although arthroplasty or high condylectomy may be necessary. An occlusal splint (mouth guard) usually relieves symptoms. The splint is worn constantly, except during meals, oral hygiene, and appliance cleaning. When symptoms resolve, the length of time that the splint is worn each day is gradually reduced. Intra-articular injection of corticosteroids may relieve symptoms but may harm the joint if repeated often.
Last full review/revision January 2013 by Noshir R. Mehta, DMD,
Content last modified January 2013
Bone Loss In the Jaw Joint (TMJ)
One of my biggest concerns for many of my patients is obvious bone loss within the jaw joints. I see this in patients as young as 12 years old. Unfortunately, this bone loss is always permanent, and it can have a significant affect on the alignment of the jaw, which can result in a severe bite problem. In the jaw joint, this type of bone loss is closest to osteoarthritis. We rarely see rheumatoid arthritis in the jaw joint, unless the patient has evidence of rheumatoid arthritis in other joints. In my practice, I see jaw joint bone loss in over half of my patients. In many cases, this bone loss may be present without any pain or dysfunction in the joint.
There are several theories regarding the cause of this bone loss. One thing we know is that the bone loss never occurs until after there has been a dislocation of the disc in the joint. This disc fits between the ball and socket of the joint, and is designed to prevent contact between these two structures. Causes of dislocated discs can include trauma or genetically weak ligaments. In addition, long-term clenching and/or grinding of the teeth can result in damage to the joint ligaments. Once the disc is displaced, bone loss can ensue if there is over-loading of the joint. Clenching and/or grinding of the teeth are the cause of jaw joint over-loading.
Recent research has demonstrated several systemic factors that can predispose females to jaw joint bone loss. One of these is low vitamin D. The other is low estrogen. Low estrogen can occur if there is a history of irregular or missed periods, or if the person is taking birth control pills containing a synthetic estrogen, known as ethanyl-estradiol. When one of these deficiencies is documented by a blood test, the bone loss in the jaw joint may be defined as “idiopathic condylar resorption.” We recommend testing for these deficiencies in our female patients with demonstrated bone loss.
This jaw joint bone loss does not necessarily mean the patient also has arthritis in other joints. Unless they have pain, stiffness, or swelling in other joints, I do not usually refer them to a rheumatologist.
Treating arthritis in jaw joints can be challenging. Conservative (non-surgical) treatment is indicated, because surgery on jaw joints with demonstrated bone loss can result in significant complications. Specifically, conservative treatment may include the use of a jaw splint designed to prevent over-loading of the TMJ. In addition, we focus on all the potential causes of clenching or grinding, including stress, poor sleep, and other harmful habits. We also recommend a number of supplements, which have been shown to reduce the risk for bone loss in the TMJ.
In most cases, this bone loss will eventually arrest itself and stabilize, if the patient follows treatment recommendations. We take follow-up CT scans, to confirm that the surface of the ball of the jaw joint is re-forming cortical bone. Once this occurs, and there has been no additional bone loss for at least 6 months, we then re-evaluate the bite problems that have occurred as a result of the bone loss. If the bone loss has been severe, extensive bite treatment is usually necessary, including orthodontic braces and sometimes surgery to re-align the jaw bones.
Here are some signs you can look for which may indicate that you are experiencing bone loss in your jaw joints:
Catching or locking in your jaw joint, which prevents normal opening or closing.
Grinding or gravel-like noise in the jaw joint when moving the jaw.
A change in the bite relationship, which prevents you from touching on one side or the other when you close your mouth.
Osteoarthritis of the Temporomandibular Joint
Osteoarthritis (OA) of the temporomandibular joint is a unilateral, degenerative disease of the jaw joint. It is characterized by breakdown of the articular cartilage, architectural changes in bone, and degeneration of the synovial tissues causing pain and/or dysfunction in functional movements of the jaw. Figures 1 and 2 illustrate an MRI and an annotated drawing of a normal joint, while Figure 3 presents an MRI of osteoarthritis of the TMJ. Until recent years, OA of the temporomandibular joint was confusing, relatively unrecognized, and difficult to diagnose and manage. Scientific research had found neither a common cause, nor a clinically useful and differentiable diagnostic test. This resulted in a diagnostic journey full of frustration, pain, and expense. Due to its multifaceted nature, the disease has no defined or linear progression of symptoms. The symptom complex is not the same from one patient to another: it can exist in a quiet state until it is set off by an array of events or it can be painful from the start.
With osteoarthritis, the jaw joint can be the first joint to get the disease, whereas in rheumatoid arthritis it is the last joint to be affected. It can be anywhere from a 3:1 or 6:1 female-to-male ratio.1 The cost of the pathology was estimated to be $16.7 billion in 1984.2 Of the patients presenting to University Florida Parker Mahan Pain Center, 16.8 percent of the patients each year have OA of the jaw joint, of which 90 percent are female with an average age of 48.3.3 Of the patients who presented to Raleigh Facial Pain Services in the years 2000 and 2001, 11 percent had OA of the jaw joint, with 86 percent being females and an average age of 51. In another pain center study, of the 200 patients having jaw joint problems, 67 percent had disc displacement with reduction, 22 percent disc displacement without reduction, and 10 percent had OA.4 Diagnosis is complicated in that there is a lack of correlation between damage and pain with radiographic evidence.5
One of the most important events in the diagnosis of osteoarthritis was the establishment of a new specialty called orofacial pain. The orofacial pain specialist is familiar with the different presentations of osteoarthritis and can coordinate the different specialties necessary to manage the problem. However since OA of the TMJ does have several different presentations, it has taken time for the diverse specialties of rheumatology, orofacial pain, physical therapy, and psychology to coordinate the requisite patient care. With the advent of new scientific and clinical knowledge, we are entering a new era of increased awareness, improved care, and improved quality of life for people afflicted with OA.
Disease Presentation
The patients who develop OA present with a variety of symptoms including pain on opening, limited movement to the opposite side, coarse grinding noise on function, history of clicking that has now stopped, and deviation on opening to the affected side. An unusually large percentage of those diagnosed are women around the age of 35.6 In addition, 31.6 percent have had a macrotrauma usually from a maximal voluntary contraction (MVC) force or even a blow to the mandible. The clinical findings are pain on palpation of lateral pole, decreased range of motion, flattened condyle, osteophytes on condyle, heavy occlusion on second molar on the affected side, facial asymmetry, and tipped Curve of Wilson. Some other indicators include loss of condylar bone which traumatizes the posterior molar on the same side, pain referral pattern to the ear, pain on eating, talking, or function of the jaw joint, jaw locking, and pain in the front tooth of a bridge due to torque forces on two molars. In summary, a picture of pain, dysfunction, and disability is involved in osteoarthritis of jaw joint.
The typical patient may have years of jaw pain, joint clicking with or without pain, disc displacement, joint dysfunction, and eventually osteoarthritis. Unfortunately, most patients are not typical. Our common perception of OA is a 70-year-old man in a nursing home with osteoarthritis of knees and hips getting OA of the jaw joint also. In reality, the most common person with OA of the jaw joint is a 33-year-old female with two kids, husband, dog, and job. Even a third grader (10-year-old female) can get OA of the jaw joint. The following is a sampling of the variations in presentations that may occur to the medical and dental professionals.
Patient #1 had recurrent unilateral ear pain for years. Frequent trips to the doctor provided no evidence of ear inflammation and rounds of antibiotics provided no benefit. Eventually, an ENT specialist then referred the patient to an orofacial pain specialist.
Patient #2 went to a dentist for frequent fractured teeth, toothaches, and recurrent abscessed teeth on the posterior teeth on one side. After several root canal, crowns, or extracted teeth on the left lower posterior area, the dentist referred the patient to an endodontist. The endodontist, feeling another root canal would not be appropriate, referred the patient to an orofacial pain specialist.
Patient #3 had years of left jaw pain with the pain suddenly shifting to the right with limited opening. The panograph revealed the left joint was severely eroded but the right joint looked apparently normal.
Patient #4 having just completed 14-unit precision bridge work on the all the upper teeth, developed pain in tooth #12 on cementation. After months of fine tuning the bridge work, she was sent to an endodontist for root canal therapy on the painful tooth. The endodontist felt it was not the tooth and recommended referral to an orofacial pain specialist, but at the insistence of the patient, performed root canal therapy with no benefit. A visit to the orofacial pain specialist confirmed OA of the temporomandibular joint.
Patient #5 presented with a bite that had suddenly changed but without any pain. This patient was correctly diagnosed with OA of the temporomandibular joint when a dentist took a panograph and found a smaller deformed condylar ball on the same side as the bite change.
Disease Inception and Progression
OA of the temporomandibular joint is a disease having a great deal of variation in progression, symptoms, epidemiology, pathophysiology, and presentation. The rate of progression from a healthy joint to a severely damaged joint of OA can vary from a very short time to decades. The fourth and fifth decades of life are the most prominent age to get OA of the jaw joint.
The pattern and rate of progression relates to the set of initiators, aggravators, and perpetuators and how they interplay with each other. There are five known factors related to the onset of—or set the stage for—osteoarthritis. These contributing factors are parafunction, occlusion, psychosocial aspects, macrotraumas, and genetics.
Parafunction Impact
In recent scientific literature, an increased importance has been placed on parafunction setting the stage for OA. In a report by Makowerowa, it was reported that 55 to 83 percent of all OA patients show evidence of parafunction (clenching or grinding their teeth).7 At the
Occlusion Aspects
The aspects of occlusion that affect both parafunction and OA are lack of anterior guidance, Class II dental and skeletal relationships, lateral interferences on posterior teeth, crossbites, loss of posterior teeth, and bite discrepancy. Bite discrepancy (when the power bite and tooth bite positions are in different locations) initiates muscle recruitment to protect the jaw and teeth.13 The mixing of different etiologies creates the distinct and differential patterns of OA development.
Psychosocial Environment
A problem associated with parafunction (clenching, grinding, and bracing) has been a nonchalant attitude by both the public and, to some extent, the dental profession, despite destructive effects seen in painful enlarged chewing muscles, gum recession, bone loss around teeth, destructive tooth wear, and now disc displacement and even OA.
Macrotrauma Impact
The macrotrauma relationship to OA has been reported as low as 5 percent14 and as high as 53 percent.15 The theory is that the jaw braces on impact, allowing the muscle to oppose the force, which stretches and tears the lateral ligament and or the elastin (retrodiscal tissue). The unique characteristic of the disc interposed between the lateral pterygoid muscle and the elastin tied down by the lateral and medial ligaments sets the stage for the pathology that is observed. The lateral aspect of the elastin and the lateral ligament are the Achilles heel of the jaw joint, partially due to the anterior medial pull of the lateral pterygoid muscle.16 Even muscle tension from stress or clenching can stretch the healthy lateral ligament and retrodiscal elastin. The hypercontraction of the lateral pterygoid can fatigue the elastin and lateral ligament, especially if macrotrauma has weakened them.
Genetic Factor
A genetic factor that has been linked to this pathology is hypermobility of joints. In a study of 74 females, 41 percent of females were hypermobile and 83 percent of the hypermobile group had TMD involvement.17 The likely explanation is that hypermobility increases the potential for the macro and microtraumas to cause damage to the lateral ligament and elastin. Even though this picture of pathology explains a great deal about the pathophysiology, it does not explain the fact that some patients have OA without disc displacement.
Management
Osteoarthritis is best managed by directing care at all initiators, aggravators, and perpetuators. This is done by a team of professionals whose specialties are associated with these etiologies. While both orofacial pain specialists and oral surgeons are trained to diagnose this condition, the orofacial pain specialist has been trained to coordinate the care. One of the biggest challenges is to coordinate the requisite group of specialists who have never spoken to each other before the dawn of this research. A typical team (in order of prevalence) may be composed of an orofacial pain specialist, a physical therapist, a biofeedback specialist, a rheumatologist, a nutritionist, and—in about three percent of the cases—an oral surgeon.
The orofacial pain specialist provides therapy to reduce parafunction, improve sleep, increase the health of the cardiovascular system, improve the capillary network to ligaments and muscle, manage the orthotic, and inject trigger points in trigeminal muscles.
The physical therapist provides reduction of inflammation, reduction of pain, and improvement of function with many different modalities such TENS, ultrasound, iontophoresis, ice and stretch, neuromuscular therapy, massage, lymphatic drainage, cardiovascular conditioning, postural and ergodynamic training, etc.
The biofeedback specialist reduces the sympathetic system up-regulation, reduces muscle tension, and serves as a coach for stress management, deep breathing exercises, and other modalities. The patient is in charge of enhancing his or her biochemistry and physiology to increase the healing response of the medical and dental therapies.
The rheumatologist manages the medications in cases where systemic diseases are also present, multiple joints are affected by arthritis, and for those severe cases needing long-term management.
The nutritionist improves the diet to provide the proper nutrients and precursors for healing of the severely damaged joints.
The oral surgeon is consulted in 3 percent of cases for arthroscopic surgery to flush out joint tissue fragments and inflammatory chemicals.18
Some other honorable mentions are Pilates, craniosacral therapy, chiropractic, rolfing, trigger point therapy, and many others that may be helpful when the muscles splint or are recruited because of the pain.
Summary
Osteoarthritis of the temporomandibular joint is a disease that affects a great many people, especially females from age 10 to 90. While not always directly correlated with pain or dysfunction, it affects the important chewing machine, causes severe pain, creates disability, affects nutrition, social, and health parameters, and is under-appreciated by the public and the health professions. Many times an OA patient has seen 7 professionals before they find their way to an orofacial pain specialist to get the proper diagnosis and complete conservative care for OA. With the advent of conservative therapy, the OA patients typically need surgical treatment in only 3 percent of the cases. The conservative therapy can last up to 3 months for the different specialties to provide the symptomatic care and prophylactic care. It is amazing how well these patients respond to removing the initiators, aggravators, and perpetuators, even with the severe destructive nature of this disease. Proper treatment by a multi-faceted team most often results in virtually pain-free living and vastly improves the quality of life for these patients.
The new research has significantly improved the quality of care for osteoarthritis of the temporomandibular joint. Improved interaction and coordination among the different health professions has improved the speed and accuracy of referrals to orofacial pain specialists. The quicker the patient is referred to an orofacial pain specialist, the easier it is to manage these problems to a successful conclusion. The patient with OA of the jaw joint is the beneficiary of the pace of research, the beginning of a new profession (orofacial pain), and the improved interaction between different specialties such as physical therapy, biofeedback, rheumatology, nutrition, and oral surgery.
Osteoarthritis
This occurs when the there is more stress put on the jaw joint than the adaptive capacity of the joint is able to handle. This can occur because of a structural problem within the jaw (i.e. trauma, disk displacements or certain bad bites) or due to excessive loading forces on the jaw joint (i.e. jaw clenching or gum chewing). The cells which make synovial fluid and the cartilage surrounding the bone are damaged before there is damage to the bone. The cartilage helps bring fluid in and out of the joint thereby eliminating waste products and bringing in nutrients. Typical symptoms include crackling or crepitation when opening and closing, pain in and around the ear, ear stuffiness, and bite shifting. This can lead to shifting of the chin to the affected side and increased bite contact on the back tooth of the affected side. When the changes are more severe there can be a noticeable facial asymmetry from the chin shifting. When disk displacements without reduction are not properly treated, unwanted osteoarthritic changes have a greater chance of occurring.
Diagram – TMJ Osteoarthritis
The temporomandibular joint (TMJ) or jaw joint is located in front of the ear on either side of the face. However, it is the only joint that the dentists and maxillofacial surgeons predominantly have to deal with. As with many of the other joints, the TMJ can be affected by osteoarthritis (OA). This is characterized by progressive destruction of the internal surfaces of the joint which can result in debilitating pain and joint noises. Several disorders other than OA may affect the TMJ and the correct diagnosis is important such that it can be matched with appropriate therapy.
A range of therapeutic options are available for TMJ OA, which include non‐surgical modalities such as control of contributory factors, occlusal appliances, cold or warm packs applied to the joint, pharmacological interventions as well as physiotherapy. Surgical treatment options include intra‐articular injections, arthrocentesis (lavage of the joint) as well as attempts at repair or replacement of portions of the TMJ.
This review found weak evidence indicating that intra‐articular injections of sodium hyaluronate (a natural constituent of cartilage) and betamethasone (an anti‐inflammatory steroid) had equivalent effectiveness in reducing pain and discomfort. Occlusal appliances when compared with diclofenac sodium (a non‐steroid anti‐inflammatory drug) showed a similar pain reduction, as did a comparison between the food supplement glucosamine and ibuprofen (a non‐steroid anti‐inflammatory).
Future studies should aim to provide reliable information about which therapeutic modality is likely to be more effective for the reduction of pain and other symptoms (e.g. joint sounds) of TMJ OA. Moreover, because the limited evidence available only covers a restricted number of interventions, comparisons with other therapeutic modalities should be encouraged. One of the authors’ concerns was the large number of trials which included mixed groups of participants diagnosed with TMJ OA, in addition to other disorders of the TMJ, which could not be considered in this review.
Abstract
Background: Osteoarthritis (OA) is the most common form of arthritis of the temporomandibular joint (TMJ), and can often lead to severe pain in the orofacial region. Management options for TMJ OA include reassurance, occlusal appliances, physical therapy, medication in addition to several surgical modalities.
Objectives: To investigate the effects of different surgical and non‐surgical therapeutic options for the management of TMJ OA in adult patients.
Selection criteria: Randomised controlled trials (RCTs) comparing any form of non‐surgical or surgical therapy for TMJ OA in adults over the age of 18 with clinical and/or radiological diagnosis of TMJ OA according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) guideline or compatible criteria.
Primary outcomes considered were pain/tenderness/discomfort in the TMJs or jaw muscles, self assessed range of mandibular movement and TMJ sounds. Secondary outcomes included the measurement of quality of life or patient satisfaction evaluated with a validated questionnaire, morphological changes of the TMJs assessed by imaging, TMJ sounds assessed by auscultation and any adverse effects.
Data collection and analysis: Two review authors screened and extracted information and data from, and independently assessed the risk of bias in the included trials.
Main results: Although three RCTs were included in this review, pooling of data in a meta‐analysis was not possible due to wide clinical diversity between the studies. The reports indicate a not dissimilar degree of effectiveness with intra‐articular injections consisting of either sodium hyaluronate or corticosteroid preparations, and an equivalent pain reduction with diclofenac sodium as compared with occlusal splints. Glucosamine appeared to be just as effective as ibuprofen for the management of TMJ OA.
Authors’ conclusions: In view of the paucity of high level evidence for the effectiveness of interventions for the management of TMJ OA, small parallel group RCTs which include participants with a clear diagnosis of TMJ OA should be encouraged and especially studies evaluating some of the possible surgical interventions.
