TEMPOROMANDIBULAR DISORDER (TMD)

Also known as TMD, this is a disorder as opposed to a disease.  One could even say that almost everyone has some degree of TMD.  First, lets define it and review the signs (conditions viewed by the dentist) and symptoms (complaints by the patient).  After we have a basic understanding of what it is, we will then move onto the causes and the treatments.  This page contains a lot of information and TMD sufferers are advised to carefully read through and, where necessary, re-read the relevant sections.  Having this information at hand will allow you to review and better digest the information.

Important Note for TMD patients about to receive dental treatments:

There are occasions when patients with TMD will have difficulty, pain and jaw discomfort during dental treatment. This is not actual discomfort from the procedure itself but rather pain due to muscle spasms as the jaw is maintained in an open position during treatment. This usually manifests part way through an appointment when the patient starts to rub/massage the jaw muscles. During the appointment, the muscles become continually more sore and overall discomfort increases, making it difficult to finish the appointment.

If this has happened to you in the past, it is recommended that you wear your brux/grinding appliance several nights prior to your appointment and that you also consider taking 400mg of Ibuprofin (Motrin, Advil, Medipren) one hour prior to the start of your procedure (If your medical condition allows this). It is also advisable to remember not to actually clench on the mouth rest/prop during the procedure but to gently allow the jaws to relax against the block. By following these guidelines, most of the discomfort can be avoided and the procedure can be completed with little incident.

Signs and/or Symptoms of TMD:

The Temporomadibular System is made up of three anatomical subsystems, all used for mastication/chewing.  These are the muscles of mastication, the teeth and the temporomandibular joint (TMJ):

MUSCLES OF MASTICATION.  These are the muscles attached to the side of your skull at one end and to the lower jaw at the other end.  Their main purpose is to move the lower jaw against the upper jaw in order to masticate/chew your food.  Signs and Symptoms of muscle involvement on TMD can include some or all of the following:

• Jaw tension and pain.
• Headaches in the temple region.
• Jaw pain on chewing.
• Limited opening.

It is interesting to note, that headaches due to TMD can often be confused with other conditions such as migraine headaches and other less common forms of headaches, e.g. Neuralgia, Atypical Facial Pain, Cluster headache, etc.  For this reason, you may be given a DIFFERENTIAL DIAGNOSIS as opposed to a (definitive) DIAGNOSIS until further diagnostic testing can be done.

TEETH.  When the teeth are involved, it is generally because they are being used at times other than chewing food.  We refer to this as PARAFUNCTION.  Parafunction is the most common cause of TMD and we will look at this further on.  For now, lets just look at the signs and symptoms of TMD, relating to the teeth.  These are:

• Dull generalized low grade sensation of a tooth ache.
• Cold and chemical sensitivity.
• Root sensitivity (to cold, touch and chemical).
• Gum recessions.
• Excessive tooth wear (attrition).
• Tooth fracture (cusp fracture).

Incisor wear and chipping resulting from parafunction.

TMJ (Temporomandibular Joint).  as with all moving parts, there needs to be a joint.  What makes the lower jaw (mandible) unique is that it is essentially one bone with two identical joints.  These two joints (left and right) are both located very close to the front of the ear holes.  To find their locations, simply put your finger on the small flap of skin(tragus) on the front of the ear hole and move your lower jaw.  You should then feel the bulge of the TMJ as it moves, especially when you move your jaw from side to side.  TMD signs and symptoms can include some or all of the following:

• Apparent sense of an ear ache.
• Joint noises on jaw movement.  These can be clicking, popping and grating sounds.
• Jaw limitations and deviations on movement.
• Pain on palpation (feeling) of the joint.

OTHER POSSIBLE INDICATORS .  In addition to the above, there are several other common signs and symptoms which may be associated with TMD.  These can include the following:

• Ringing in the ear(s).  This generally comes and goes and is not constant.  This is also referred to as tinnitus.
• Dizziness/lack of balance.  Also called vertigo.
• Tearing of the eye(s) (lacrimation).
• Sense of nausea.

It is very important to remember that there are several other conditions which can easily be confused with TMD.  Just because you have all or some of these symptoms, you must avoid self diagnosis.  Further testing is usually required in order to make the definitive diagnosis.

Causes of TMD:

The most important aspect of TMD is understanding the CAUSES.  Causes of TMD include the following:

• Parafunction (clenching, grinding, gum chewing and other oral habits).
• Trauma (falls, bike and automobile accidents, etc.).
• Arthritis (osteoid, rheumatoid, gouty, etc.).
• Overextension (singing, unusual eating patterns).
• Diseases (bone growths, tumours, etc.).

Of all the causes of TMD, parafunction accounts for the vast majority of cases with trauma being a very very distant second.  In today's society, it seems that the stress and strain of daily life seems to be causing more and more people to grind and clench their teeth.  I am sure we can all relate to times in our life when stress has caused us to clench or adopt other nervous habits.  Sufferers of TMD due to parafunction may not be aware of their habit since they do not do it consciously, especially when they do it in their sleep.  Let's look at the various factors individually:

SLEEP.  Believe it or not, sleeping patterns are probably among the most destructive aspects for many of us.  Frequently, the dentist can view the wear patterns of the teeth and determine the sleeping patterns leading to the tooth wear.  We refer to this as a DESTRUCTIVE SLEEPING PATTERN (DSP).  DSPs are usually side and stomach sleeping patterns where the patient has a twist in their spine during sleep.  At the same, time, they frequently hold their hands/arms up to the face or place the pillows or blanket rolls under the jaw.  Sometimes side sleeping patterns are a result of the patient being awakened by a sleeping partner as a result of snoring.  TMD as a result of DSPs may not be the only problem. Many times, DSPs may lead to other problems such as wrist, neck, upper/lower back and shoulder problems.  It is frequently seen that TMD sufferers commonly see other health practitioners, such as physicians, chiropractors, physiotherapists, massage therapists, etc, for relief of carpal tunnel syndrome (where do you place your hands during sleep?), and upper body and shoulder soreness.  One possible clue that you have a DSP is if you wake up feeling worse than when you go to bed.  People with DSPs commonly wake up and complain of jaw soreness, sensitive teeth, sore shoulders, neck, back and wrist.  Remember, it is very common for DSP sufferers to wear wrist and neck braces as well as frequent allied health care professionals.  

Hand position during sleep - part of a destructive sleep pattern.

Roll over image to reveal how a DSP causes incisor wear/chipping.

As mentioned, DSPs due to a person's habit of sleeping may cause the above problems.  On the other hand, DSPs may be caused by some of these problems as well.  Other than sleeping on a poor mattress, or being turned over due to excessive snoring, some TMD sufferers have adopted a DSP because of a sore shoulder or hip or any other physical condition that may influence their sleeping pattern.  Occasionally, pregnancy may fall into this category.

Being aware of DSPs is the first step to treatment.  As an exercise, we recommend you look in a mirror and put your front teeth together until the wear patterns match.  This is usually when you cannot see any space between the teeth. Then lie down in your bed and figure out which position allows you to do this.

Important note on parafunction:  In all cases where parafunction is the cause, it simply means that the teeth are touching when they are not supposed to be.  In normal rest position, the teeth are generally 1 to 4mm apart and the muscles are at rest.  Function of the teeth with regard to chewing means that the teeth and muscles are used for approximately 17 minutes every day.  That's how much the average person actually makes chewing tooth-contact every day.  Imagine what happens when you put those teeth under additional heavy load.  Remember, the teeth cannot touch unless the muscles are in contraction.  Once you load the system, now the teeth, muscles and jaw joints (temporomandibular) become involved.  Now imagine doing this for several hours a day under a heavy load.  This now becomes a self-destructive process.

POSTURE.  (Although sleep posture technically belongs here,  we have dealt with this separately in the preceding paragraphs.)  Typically, postures with a head-forward position, can typically promote parafuction during the day time.  Some people naturally hold their head in that position during the day whether walking, standing or sitting.  More commonly, head-forward positions may be work associated with arm-forward postures.  The most typical will include computer/keyboard positions and professional drivers.  Doing these activities all day long and concentrating on the task at hand can lead to grinding and clenching habits.  As a general rule, the TMD symptoms and signs due to work related posture tend to worsen during the day and are the worst in the evening.

BEHAVIOUR/HABIT.  For whatever reason, people with little or no predisposing factors engage in parafunction simply due to habit.  It has been reported that females whose mothers are grinders/clenchers, are six times more likely to do the same.  Whatever the association here, it is more likely a learned behaviour than a genetic association.  Once the person develops the habit, it becomes a destructive cycle where pain seems to make it more desirable for the sufferer to continue parafunctional habits.

Treatments for TMD:

Now that we have looked at the diagnosis and some of the causes of TMD, lets look at some of the treatments available to us:

AWARENESS.  Although some have coined the term 'COGNITIVE AWARENESS',  simple awareness and the attempt to consciously alter parafuctional behaviour has been credited with 20-30 % improvement in some instances.  This is most useful during the daytime.  In some instances, people have placed an elastic band around their  wrist and whenever it has caused mild irritation, they immediately focus on their jaws.  'LIPS TOGETHER - TEETH APART'  is the common mantra at this point.  Believe it or not, this actually works.  Other useful ways would be to use some kind of alarm system (e.g. wrist watch) which reminds the patient every hour to be cognizant of their jaw position.  Interestingly, one of the tools with the greatest potential for behavioural modification with respect to TMD is the biofeedback machine.  Commonly used by psychologists, electrodes can be placed near the muscles and give a biofeedback alarm during muscle activity.  Although this sounds fantastic in theory, its lack of practicality has made this less than useful.

SLEEP (DSP) MODIFICATION.   This is a 'biggy'.  Although it sounds simple in theory, it is very difficult to change people's habits.  Consider the following factors in changing sleeping patterns.

• Mattress/Bed.  For some, it is just a simple matter of a new mattress and/or bed.  DSPs may be a result of a poor mattress.  
• Toes and Nose.  We council our patients to maintain a TOES AND NOSE IN THE SAME DIRECTION sleeping posture.  This means, your toes and nose should be pointing in the same direction when you are sleeping.  Another way of putting it, is that you should be sleeping without any twist in your spine.  This includes your head and neck.
• Pre-bedtime behaviour.  Stomach sleeping, if not already a habit, can increase and get more common as the night wears on.  Consider that sleep research has shown an increase in heart rate, blood pressure, bladder pressure and jaw muscle activity (hence grinding) as the night wears on and the patient enters more intense dreaming stages.  It appears that as bladder pressure increases, the patient is more likely to flip onto their  stomach and press their pubic area against the mattress.  As a result, psychologists have suggested altering pre-bedtime consumption of liquids and snacks.  A general recommendation is to consume nothing within four to six hours prior to your bedtime and to relieve your bladder before going to bed.  Snacking and drinking of stimulants, such as coffee, tea, Cocoa, cakes, cookies and such prior to bedtime will frequently increase the unwanted aspects of your sleep.  If you must snack, it is recommended to eat raw fruit and vegetables and drink water.  If you must drink water, then reduce the amounts as much as possible.
• 'Sleep Reset'.  What this means, is that if you wake up during the night and find that you are in a DSP, get up, relieve your bladder and then reset your sleep posture to a neutral 'toes to nose' position.  Remember, it doesn't seem to work unless you relieve your bladder.  In some difficult cases, we have recommended patients set an alarm clock in order to do a 'sleep reset'.  This is in cases where the patient sleeps through everything, including a  very resilient high-capacity bladder!
• Snoring.  Dealing with a partner who snores can be helpful at times. Whether you sleep in different rooms/houses or medically deal with snoring and sleep apnoea problems can bring some relief.

In addition to the above, some psychologists have recommended simple tricks which may help a person have a better sleep in general.  Some of the self-help books on the market can be quite useful as well.  Some things to remember might include:

• Stress reduction techniques, e.g. counselling, yoga, pilates, transcendental meditation, etc.
• Mild exercise before bedtime.  Over exercise may have the opposite effect.
• Stress release.  One psychologist found that an effective tool for pre-bedtime stress release was to take a tennis ball and write the name of the object(s) causing your stress.  You would then take a tennis racquet and then bash the ball repeatedly against the garage wall.  Don't laugh!
• Have a consistent bedtime each night.
• Get up and read if you can't sleep. It usually doesn't take too long before you feel tired and then go back to sleep.

PHYSIOTHERAPY, MASSAGE THERAPY AND CHIROPRACTIC TREATMENTS.  In some instances, one or more of these treatment modalities can be very helpful in improving any back, neck, hip or shoulder problems that might be affecting the way you sleep.  In addition, they may help you change your posture (limb length discrepancies are not uncommon), your sleeping posture, driving/work postures as well as your head/jaw posture.

MEDICAL TREATMENT.  Occasionally, after hip replacement or shoulder surgery, the patient may return to a better sleeping position.

DENTAL TREATMENT.  In addition to the above modifications, there are several effective treatments we can perform to help relieve TMD.  Above all, you must realize that we cannot TREAT your TMD, but only alleviate it.  What we are saying is that the cause of TMD is rarely dental in origin.  In most cases, stress reduction and behaviour modification would be the true treatments.  Nonetheless, it is still necessary to treat the dental effects of TMD.  These treatments might include the following:

• Brux Guard.  Also known as a grinding, bruxing or night guard/appliance, this appliance can have several forms.  Bruxing is defined as grinding.  First, a bruxing appliance is generally first thought of as a diagnostic tool.  What we mean by this is that wearing this appliance may finally help us to make a definitive diagnosis that the patient is suffering from TMD.  If there are no changes in the signs and symptoms you are experiencing, then it may be that you are suffering from some other source of discomfort/pain.  This is no different than ordering a blood test and getting a negative result.  It is still a very useful exercise.  In the event that it does prove useful, it now becomes a therapeutic device in that it is worn in order to reduce common signs and symptoms associated with bruxing.  Although it would be our intention to wean you off of this appliance at some point, it may be worn indefinitely.  It should be checked frequently and may require modification or replacement, if you have any subsequent dental work done.  In that case, it may no longer fit over the teeth.  A brux guard will generally have two effects. First, it may help you stop bruxing while wearing the appliance or, second, in the event that you continue to brux on the appliance, it will lessen the destructive forces of bruxing as well as reduce the wear and stress on the teeth, muscles and jaw joints.  This is due to the mechanical design of the appliance as well as the fact that the hard-processed acrylic is softer than your enamel.

* Note:  In most cases, brux guards are tolerated with little or no problems.  In fact, many patients will refuse to sleep without it.  In some cases, these appliances may not be tolerated by some sensitive patients.  It may make some people feel that they have too much foreign substance in their mouth.  This may be due to a sense of crowding the tongue or gagging and may be alleviated by making a lower appliance instead.  In other instances, wearing a thin brux guard may still separate the patient's lips during sleep when they weren't separated before.  In the event, this happens, drooling and mouth breathing may be a common complaint.  Where this condition existed before hand, it is not significant.  Again, we must emphasize, that the brux guard is a diagnostic appliance and we cannot guarantee that all patients will tolerate it.  We rely on the patient's commitment to wear it.

• Bite adjustment.  Where the bite of the teeth, does not match the actual orthopaedic bite (that of the jaw muscles and jaw joint), it can be modified by selective grinding until the two are the 'same'.    This treatment rarely requires any anaesthetic and usually requires filling and tooth removal that the patient is already trying to grind away. Frequently, following bite adjustment, the patient reports improved jaw comfort and a better sense of ' bite'.  It is interesting to note that bite adjustment may still not reduce grinding even though the patient feels a sense of relief.  This is usually due to the alteration of the destructive mechanical levers due to the misalignment of the teeth.  This may make more sense when you think of the teeth as pinking shears or gear wheels.  When the cogs are out of alignment, they do not work properly either.  Another way to look at it is to consider an analogy with a wheel alignment on your car.  In the situation where there are steering problems or uneven tire wear exists, a wheel alignment can be very useful  Frequently, when brux guard therapy has proved useful, we will follow up with a bite adjustment.  Since the bite adjustment will endeavour to give you the same bite as the  brux guard, the brux guard will be used in exactly the same way and work as it had before  without any modification. 
• Restorative therapy.  This entails modification of the teeth.  This can be as simple as re-shaping the teeth and/or restoring some of the teeth with crowns and/or veneers in order to reduce destructive mechanical levers within the bite.  In very rare instances, the entire bite may need to be restored.  This therapy can also be done in conjunction with a bite adjustment and usually is best done following an adjustment.  Think of it as doing a wheel alignment prior to putting on new tires on your car.
• Orthodontic therapy.  In the instance where the bite mechanics can be improved by shifting the teeth, an orthodontic consult may be required.  In severe cases, an oral and maxillofacial surgeon may be consulted where gross jaw discrepancies exit.
• Surgical therapy.  In the event where severe joint damage has occurred and the patient has significant jaw limitations and pain, it may be useful to seek a surgical consultation.  This is quite rare and is usually of limited use.

Important Note for TMD patients about to receive dental treatments:

There are occasions when patients with TMD will have difficulty, pain and jaw discomfort during dental treatment. This is not actual discomfort from the procedure itself but rather pain due to muscle spasms as the jaw is maintained in an open position during treatment. This usually manifests part way through an appointment when the patient starts to rub/massage the jaw muscles. During the appointment, the muscles become continually more sore and overall discomfort increases, making it difficult to finish the appointment.

If this has happened to you in the past, it is recommended that you wear your brux/grinding appliance several nights prior to your appointment and that you also consider taking 400mg of Ibuprofin (Motrin, Advil, Medipren) one hour prior to the start of your procedure (If your medical condition allows this). It is also advisable to remember not to actually clench on the mouth rest/prop during the procedure but to gently allow the jaws to relax against the block. By following these guidelines, most of the discomfort can be avoided and the procedure can be completed with little incident.

We hope you have found this information useful.  If you have any further questions, please do not hesitate to contact us by or by phone (604.224.2411).  If you know other people  who may be suffering from TMD, please feel free to send this informative page to them.  Many people may complain of these symptoms or believe they have migraine headaches without knowing they have TMD.   

E-mail This Page