TMJ Dysfunction (TMD) is a popular term to describe a disorder of the jaw joints or the muscles that control the joints. Various terms are used to describe this disorder which also known as "Craniomandibular Dysfunction, TMJ, TMD, MPD or CPD”. Symptoms masquerade as a multitude of other problems such as sinus headaches, migraines, neck and shoulder stiffness and earaches. This section explains how such symptoms may relate to your bite and how they can successfully and permanently be treated by a specialist who has special required education in managing these disorders.
TMJ dysfunction is a dental term which describes a collection of symptoms which result when the chewing muscles and jaw joints do not work together correctly. "TMJ" is a popular term commonly used to describe the same group of symptoms. TMJ stands for Temporomandibular Joint. These are the two joints that connect your jaw to your skull. When these joints are out of place, they can cause many problems, such as:
- Clicking or popping of the jaw joints
- Pain in or around the jaw joints
- Locking or limited opening of the mouth
Muscle spasm goes hand-in-hand with displaced jaw joints. Because the nerves and muscles are so complex in this area, when these muscles are in spasm the problems can be far-reaching. People suffer from symptoms they would never think to associate with their bite, such as:
- Pain behind the eyes
- Earaches or ringing of the ears
- Clenching or grinding of the teeth
- Neck, shoulder, or back pain
- Numbness or tingling of the fingers
The primary problem can be in the joints themselves, the muscles of the face and jaw, or a combination of these.
Although commonly the presence of jaw pain and headaches are considered the criteria for diagnosis to start treatment for TMJ problems, most of the TMJ disease sufferers are left undiagnosed and untreated since they are not in pain at the moment. The biggest misconception about the TMJ disorders is that although sometimes are associated with jaw pain, headaches and discomfort but most of the time the adaptive changes in the structures of the TM joints or facial components can take place without any pain or discomfort. This so called dormant stage can continues for years or decades of patient’s life, alerting the dental structures (tooth wear, fractured teeth, receding gums), facial structures (receding lower jaw, receding chin, facial asymmetry), airway structures (snoring, upper airway resistance syndrome, obstructive sleep apnea), until the emotional stress as added component lowers patient’s physiological tolerance and then become a painful entity commonly known or treated as TMJ pain. Unfortunately since the common criteria for onset and diagnosis of the TMJ associated problems is based on the presence of pain or discomfort, affected patients can suffer and progress through more life threatening derivatives of TMJ related problems including; obstructive sleep apnea and its related byproducts, high blood pressure, chronic heart failure, heart attack or stroke without complaining of any jaw pain, headaches or discomfort.
Until recently, treatments for these types of jaw pain and headache sufferers have been confined to various palliative methods with marginal success. Pharmacologic, psychologic and biofeedback approaches to address the pain only, although have helped some of these individuals temporarily, but made the most, lifetime chronic jaw pain and headache sufferers even if they preferred to avoid long term drug, biofeedback or psychological care.
Our treatment strategy to resolve the TMJ related problems such as jaw pain, facial pain, headaches including triggered migraine types is not to suppress or just cover-up the symptoms with drugs. The permanent treatment of TMJ problems is accomplished by providing proper orthopedic relation of jaws, teeth and TM joints with harmonious neuromuscular function. Our main goal is not only to discover and correct the cause of the TMJ problem permanently, but eliminate the chance for development of its byproducts like facial deformities and premature aging of the oro-facial components as well as its associated health threatening side effects like obstructive sleep apnea . Also avoid complicated treatment modalities such as TMJ surgery. This is the most important benefit of permanent correction versus palliative treatment of TMJ problems.
What Causes Craniomandibular or TMJ Dysfunction?
The structures that make it possible to open and close your mouth include the bones, joints, and muscles. These are very specialized and must work together whenever you chew, speak, or swallow.
Your teeth are inserted in your jaw bone. At the other end of your jaw bone are the temporomandibular joints. These joints attach your jaw to your skull. Muscles attach both the bones and joints and allow them to move. Any problem which prevents the complex system of muscles, bones, and joints from working together in harmony may result in Craniomandibular Dysfunction.
A "Bad Bite"
The resting relationship of the movable mandible (lower jaw) to the fixed maxilla (upper jaw) and base of skull is influenced by many factors. These include dental occlusion, respiration, TM joint anatomy, muscle function, cervical posture, and tongue position. There are various ways this system can be disrupted, such as accidents involving a blow to the face or a whiplash, while the most common cause of Craniomandibular Dysfunction relates to your teeth and your bite. If your bite isn't right, it can affect both the muscles and the joints. What do we mean by a "bad bite?" We mean that your upper and lower teeth do not come together in a way that provides the proper bracing support for your jaw against your skull. This might result from a missing tooth, mis-aligned teeth, or back teeth which are too "short."
Your upper and lower teeth must come together firmly each time you swallow. This happens over 2000 times each day and night! When your bite is unstable your muscles must work extra hard. This extra work makes them shortened and stiff. Eventually this strain makes them feel painful. A vicious cycle begins of increased tissue damage, muscle tenderness, and pain. The pain makes you feel tense and uptight. This worsens the muscle spasm, which in turn increases the pain.
Jaw Joint Displacement
The position of your teeth can also affect the position of your jaw joints. Each jaw joint is a ball and socket joint. When functioning properly, the ball and socket do not actually touch because a thin disc of cartilage rides between them. The disc acts as a cushion and allows the joint to move smoothly. Each disc is held in place and guided by muscle. If your bite is not right, the joint is pulled out of alignment. Typically the disc is pulled forward. Since it no longer serves as a cushion, the joint itself now rubs against the bony socket and presses on pain fibers. Mild displacements cause a clicking or popping sound in the jaw joint; more severe displacements can be very painful and limit the opening and side to side movement of the lower jaw which is called locked jaw. this condition eventually can cause permanent damage to the joint condyles and cause shortening of the lower jaw on one side (facial asymmetry) or both side (small lower jaw and receded chin).
An unstable bite can cause both jaw and jaw joint displacement, muscle strain and pain. Many seemingly unrelated symptoms result which are collectively known as Craniomandibular Dysjunction.
When this condition is prolonged, the body begins to compensate and adapt by involving muscles in the neck, back, and even sometimes those of the arms, fingers, pelvis, legs and feet.
Headache or Facial Pain caused by Myofascial Pain- Dysfunction (MPD)
New research (Lynn, et al, 1991) has uncovered more of the mysteries of the causes or sources of this type of headaches. The way muscles and bones move above the shoulders differs significantly from the other extremities in many respects. This is an area where right and left nerves, muscles, and vessels must work together. This is essential because the right and left tissue systems are affecting movements of single bones, in essence the mandible (lower jaw) and the cranium (skull). The result of restoring normal physiologic parameters of unbalanced systems was sustained pain relief.
Medical or Biochemical Aspects
When these synergistic or balanced antagonistic tissue systems are unbalanced (asymmetrical motor neuropathic dysfunction), then the right and left components or the elevator or depressor components become dominant. This results in muscle hypertonicity (spasm) at rest or ineffective performance during function. The end product of constant resting muscle hyperactivity (spasm) is decreased blood flow through regional vascular beds (vascular instability). This causes a change in the metabolic path for the production of energy from aerobic metabolism to anaerobic metabolism. The end product of anaerobic metabolism is lactic acid, which is a spasmodic itself and a localized tissue irritant thus causing more spasm and pain. The neurovasomuscular system of the head and neck develop, through life, into functional (efficient) or dysfunctional (inefficient) patterns, much like a person learning to swing a golf club correctly or incorrectly. There is no genetic predetermined pattern of function or dysfunction. The neuromuscular pattern of function or rest, modulated through the reticular activating system is one the body has adapted to either with or without symptoms (pain or headaches). When the individual’s ability to accommodate is exceeded, symptoms occur. Emotional stress has a great impact in lowering individual’s ability to adapt. In the symptomatic individuals, the body's adaptive mechanisms have fallen behind the pathophysiologic dysfunctional patterns. Although sometimes the metabolic changes are subtle, but the pain produced is significant.
Permanent relief from TMJ associated problems and its related headaches Is available
Today, new computerized imaging technologies like Cone Beam Computed Tomography (CBCT) and Magnetic Resonance Imaging (MRI) combined with other state-of-the-art, computerized, diagnostic equipment affords specially trained professionals the ability to diagnose and determine the extent and location of abnormal craniofacial musculoskeletal patterns. In many conditions, an orthopedically designed maxillary (upper jaw) orthotic to be worn between the teeth is necessary to stabilize the compromised (neurovasomuscular) tissues. This orthotic promotes tissue healing by providing orthopedic stability of jaws, TM joints, teeth and neuromuscular components in much the same way as a cast allows a broken bone to heal. Proper stabilization of dysfunctional tissue systems results in restoring them to functional patterns. The metabolic abnormalities are eliminated and therefore the pain is relieved. Once these tissue systems are restored to normal functional patterns, there are several treatment options available to the patient for definitive correction of the craniofacial relation to maintain permanent pain relief.
This physiologic-based treatment has allowed 80 - 100% pain relief in 95% of the patients treated with this approach. The opportunity to experience life without headaches is the result of these new computerized technologies and treatment techniques.
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What causesmyofascial pain dysfunction (MPD) associated with TMJ dysfunction?
We do not think of a person "catching" a heart attack or cancer overnight. Similarly, most people do not "catch" MPD. As a chronic degenerative disease it often takes years to develop. Since we will not find a simple virus, we must consider many different contributing factors.
Have you ever seen a jaw come walking into a dentist's office by itself? We hope not! That jaw happens to be attached to a whole person with a unique personality. This is why we must consider many different aspects of the individual when discussing the cause. We will divide these aspects into three groups: structural, emotional, and biochemical. All of these components are disturbed to some extent when a person suffers from TMJ dysfunction or related MPD.
When diagnosing TMD, we will try to assess the relative impact of each of these components. This will help to determine the most effective course of treatment for you.
It may be that you were not aware of any symptoms until you woke up one day with, for example, an excruciating headache. To explain this, June Biermann and Barbara Toohey in their book, Women's Holistic Headache Relief Book, developed their Dam Theory for those "damn headaches."
They compare headaches to a dam, behind which there is a reservoir. Rain, hail, sleet, snow, and various runoffs all cause the water level behind the dam to rise. When too many of these factors combine, the water spills over the dam, causing a devastating flood in the valley below.
Similarly, many different lifestyle factors can combine which could aggravate TMD - such as structural imbalances, stress, fatigue, certain foods and drinks and even chewing gum. Any one of these is a single drop in the bucket, but taken together, they precipitate into a full-blown TMD or MPD condition.
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There is always an underlying structural weakness behind TMD and MPD. Nearly all of us have a structural weak spot somewhere in our bodies. For some people, it is their stomach, and they are prone to ulcers. For others, it is their heart, and they are prone to heart attacks. For you, it is your jaw, and this is why you are prone to TMD or MPD.
Your structural weakness stems from a condition which dentists call "mal-occlusion" (literally: "bad bite"). This means that your upper and lower teeth do not close together in the right way. Just as a table needs four legs firmly on the floor for support, your teeth must fit properly and evenly together to support the jaws and temporomandibular joints to provide efficient neuromuscular function in your face for chewing and swallowing.
Your teeth are part of your skeletal system. They are attached to your jawbone, or mandible, which is one of the 206 bones in your body. The mandible looks something like this:
You can see that your jaw is attached to your head, or temporal bone, by your temporomandibular joints. These two joints happen to be the most complex in your entire body. They are ball and socket joints which have the unique capability of moving in three directions simultaneously - up or down, forward or backward, and to the left or right.
It is important to realize that both your temporomandibular joints and teeth are part of the same bone. The position of your temporomandibular joints is determined by the way in which your upper and lower teeth close together. When your upper and lower teeth are closed together, they are in occlusion. Your occlusion dictates the position of your jaw in relation to your skull. Dentists call this the Craniomandibular relationship.
Malocclusion is when your bite is such that your skeletal system is in disharmony with your neuromuscular system. This means that your teeth are forcing the muscles of your face and jaw into a strained and unnatural position.
Malocclusion, or a "bad bite," can be caused by something extreme, such as a whiplash injury or a blow to the head. But even minor changes, such as a missing tooth, crocked teeth or a high filling, by creating malocclusion can result in TMD or MPD.
You probably never connected a missing tooth or bad bite with your headaches. Most people don't, which is why most TMD problems and its related headaches know as MPD are so puzzling. Yet, if your teeth are not providing the proper bracing support for your jaw against your skull, the muscles of your face and jaw compensate by forcing your teeth to come together for chewing and swallowing. Since you swallow at least once each minute, this means your teeth close together over 1000-2000 times each day and night. When the jaw must twist, or torque, in order for the teeth to close together, the muscles are put into a strained and unnatural position. This muscle spasm is the key to myofascial pain and related headaches.
Imagine if you had to sit on a chair which had a nail poking out one side of it. Since you would not want to sit on the nail (and probably prefer not to sit on the chair), you would torque your body to one side and hold up one hip.
After a while, this position would become extremely uncomfortable and certain parts of your body would start to feel pretty sore. This is the same thing that happens to the muscles of your face when they are forced into an unnatural position because of your bite. Eventually the strained muscles become sore and painful.
Not only do the muscles of your face and jaw become sore because of this constant strain, but they also shorten. This can cause problems in the muscles of your neck, head, back and even down into your chest. In patients who present with mandibular orthopedic discrepancy as well as cervical discomfort, jaw orthopedics must be evaluated as the primary or secondary stressor for cervical pain and dysfunction.
Your head sits delicately balanced on top of your neck because of a complex coordination of these muscles. Imagine it as a baseball balanced on top of a pencil and held in place by a number of rubber bands. Now imagine shortening just one of those rubber bands; some would stretch, some would shorten, and the baseball would be thrown off kilter! Similarly, when even a single jaw, neck or shoulder muscle becomes shortened, all of the other muscles are forced to overwork to keep the head balanced on top of the spinal column.
Muscles which are under constant strain can develop "trigger points." These feel like knots, or nodules, which are painful when you press on them.
A trigger point is a hyperirritable spot in a muscle that is painful to palpation. It is called a trigger point because it “triggers” a painful response. A trigger point is more than a tender nodule. It affects not only the muscle within which the trigger point is located, but also causes “referred pain” to distant and seemingly unrelated sites. Trigger points are located in a taut band of muscles fibers. The trigger point is the tenderest point in the band. Sometimes trigger points in the neck and shoulder area can be the source of referred pain causing jaw pain or headaches. Referred pain is when a pain originates in a part of the body like neck and shoulder area that differs from the area where it is felt as headaches or jaw pain. These can be tricky to detect, because the painful area is not the source of the problem. We are able to detect the real source of pain by mapping the referred pain patterns. The majority of TMD complaints are of muscle dysfunction origin and every patient should be carefully examined of myofascial trigger points, which can be associated with their symptoms. Following a comprehensive diagnostic evaluation, if trigger points are identified, these areas should be treated and eliminated prior to any significant surgical or medication intervention.
You see that people who suffer from TMD or MPD have a structural imbalance in their jaw-to-skull relationship which creates a vicious cycle.
This is caused by a bad bite (malocclusion) which has two consequences. First, it alters the position of your temporomandibular joints and places excessive pressure on the nerve-filled area surrounding them and develops TMD with associated jaw as well as facial pain. Second, it twists, or torques, your head, neck and shoulders into a strained position. This can cause MPD and affect the muscles in your face, head, neck, back as well as shoulders. The presence of one can initiate the other one and vise verse. Muscles under constant strain are painful!
To stop this vicious cycle, the jaw must be brought back into a musculoskeletaly balanced position.
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Diagnosis of TMD/MPD
MPD is often called "the great imposter." No wonder! Because of the number and variety of symptoms it is difficult to detect. How many people would think of visiting a dentist if suffering from headaches, ear pain/stuffiness, or neck pain? Consequently many go from doctor to doctor trying to find relief. This can be extremely frustrating--and costly! You may even begin to wonder, "am I crazy?" Since MPD is so seldom recognized, people who suffer from it often receive little support.
This is why an accurate diagnosis is so important. It is the key to successful treatment. Below is an outline of a diagnostic procedure. The doctor may use any or all of these procedures to arrive at a diagnosis:
- An interview to discuss your medical history in relation to your TMD /MPD condition, onset of pain, symptoms, and contributing factors.
- A clinical examination to explore tenderness in the muscle groups of your jaw, head, neck and shoulders, as well as your teeth and bite, and other related factors such as ear blockage and posture.
- X-rays of your jaw joints in opened, closed and rest position.
- Casts (models) of your teeth mounted on articulator (jaw function simulator) to obtain a record of your biting and chewing pattern.
- An analysis of your jaw movements.
- An analysis of your muscle activity.
- Recording of jaw joint sounds with Doppler (ultrasound device).
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Once all diagnostic information is collected, we can determine the best course of treatment. Typically, treatment will follow these steps:
- Stabilize the bite. When muscles have been tight for a long time, it takes a while for them to relax. This is one of the most effective ways to do this. During this phase, the bite can be temporarily corrected with the help of an orthotic which also called splint, which fits over the teeth. This allows us to make easy adjustments of your bite until it reaches a stable position to orthopedically support the temporomandibular joints. Once symptoms are relieved and the bite is stabilized, then it can be permanently built to the correct position.
- Relieve muscle spasm and pain. Sometimes moist heat pack/ice pack applied to the face or muscle massage as well as physical therapy for the head, neck and TM joints will also help. Occasionally but not often anti-inflammatory medications or mild muscle relaxant drugs are prescribed. We avoid using the pain medications as only modality to comfort the discomfort since it just masks the pain when the damage still in progress.
- Permanent treatment. There are various ways that your bite can be corrected in a permanent way and as result cure the TMJ/MPD problems permanently. Below are five approaches:
- Coronoplasty/Equilibration -- selectively reshaping the contours of the teeth to correct the bite. This is a fairly simple procedure which can be used when the bite has minor discrepancies.
- Removable Overlay Partials -- permanent orthotics which are designed to maintain an accurate and stable bite.
- Reconstruction -- adding height or reshape the teeth by use of restorations or crowns to provide structural support for the bite and ultimately the TM joints.
- Orthodontics and PharyngOroFacial orthopedic treatment (Orthopedically and functionally oriented orthodontics) this treatment modality is based on the use of customized mouthpieces (orthotics) to obtain a comfortable position for the lower jaw. Once this jaw position is found and the TMJ problem is under control, long-term stabilization can be accomplished with functional orthodontic treatment to allow the natural teeth to serve as an orthotic. Teeth in both children and adults can be moved to the correct neuromusculoskeletal position. This approach is contrary to the cosmetic orthodontic treatment that is aimed at just alignment and beauty of the bite and teeth. Although it has an equally significant impact on improving the esthetic of dentition as well as face, it is geared toward ideal alignment/coordination of the teeth, jaws, temporomandibular joints and neuromusculoskeletal system. Along with this, also provides an ideal and functional airway to improve the sleep disordered breathing conditions like snoring, upper airway resistance syndrome (UARS) and obstructive sleep apnea (OSA) and their side effects sleep bruxism (grinding during sleep). The presence of UARS or OSA caused by small jaws or constricted dental arch forms indirectly by enhancing sleep bruxism (nocturnal grinding/clenching) promote or increase the TMD/MPD symptoms.
- Orthognathic (Jaw) Surgery -- in a very small percentage of cases, surgical realignment of the upper and lower jaws may be required to correct the bite and airway.
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What Is An Orthotic?
Orthotics are known by various names, such as splint, or bite guard. The term orthotic is most accurate because it means a mechanical appliance designed for orthopedic use. This orthotic is worn between the teeth in order to quickly improve the orthopedic stability of the jaws to interrupt clenching or grinding activity and to allow a more comfortable, relaxed jaw position. This appliance is customized for each patient by taking the plaster models of the teeth and mounting them in articulator, a simulator of patient’s jaw function.
Orthotics are also made in various ways. Typically are made of lightweight clear acrylic to fit over the upper teeth and sometimes the lower teeth. In most cases this orthotic can be made very small and invisible.
What Will the Orthotic Feel Like?
The purpose of the orthotic is to change the way the teeth close together so that the muscles are balanced. It is hard to predict how you will feel at first. Sometimes it takes a short period of time to get accustomed to having something over your teeth.
Eventually, you will become very used to this new position and it will feel strange when your remove the orthotic. Your teeth will feel "lost". They will miss the support. Many patients find that once accustomed to the orthotic, a headache begins shortly after removing it. This usually stops once it is replaced in the mouth. Again, this vividly shows that your teeth must have this extra support in order for the muscles to relax
Will People Notice That I'm Wearing an Orthotic?
The orthotic or splint designed by Dr. Yousefian, when worn, most of the time is hidden behind upper teeth not showing at all or barely noticeable. The front portion is usually a thin, clear acrylic strip which most people will probably never notice.
How Long Will I Wear an Orthotic?
This is difficult to estimate because each patient is unique. Initially, we must check the orthotic frequently once a week at most until the pain is gone then once every four to six weeks. As your muscles are changing, they may wear or otherwise change the acrylic surface of the orthotic. Gradually, your bite will begin to stabilize and the orthotic will require less frequent checks.
Why Can't I Permanently Wear an Orthotic?
There are several reasons:
- It is usually made of acrylic which does wear down over time.
- Long-term wearing is not hygienic; it can become an irritant to gum tissue.
Some orthotics have been designed that are appropriate for long term use, and this is something you may wish to discuss with your TMJ specialist although by now you understand that a permanent treatment for the TMD or MPD is also available.
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