The upper stabilization appliance is a removeable plastic mouthpiece which fits over all the upper teeth and contacts all the lower teeth. It uses ramps of various shapes to protect the TMJs and the teeth as well as a tall stable bite table which restores normal resting length to tight contracted jaw muscles. Wearing the right type of stabilization appliance every night and ensuring the maintenance of a stable natural bite is all that  most TMJ disorder patients need for permanent symptom relief.   A few patients need supportive therapies, a few need more TMJ protective appliances (such as telescopic appliances), and a few need changes (usually minor) in their natural bites. Rarely is more extensive treatment required. 

 

Although it is primarily worn at night, the upper stabilization appliance is very different than the nightguards which are routinely made by general dentists. Nightguards are designed to protect the teeth from wear by interposing a layer of plastic between the teeth.  Nightguards are not designed to protect the TMJs or the jaw muscles, so their effect on TMJ disorders is random. They could make the problem better, they could make it worse, or they could have no effect on it.  Upper stabilization appliances protect the teeth from wear (just as nightguards do), but they are also designed to maintain the health of the periodontium (gums), protect the TMJs, and stretch the jaw muscles.

 

Unlike nightguards, upper stabilization appliances maintain the health of the gums (the periodontium) by protecting the teeth from the wiggling forces which are caused by nocturnal grinding and clenching.   These wiggling forces can aggravate gum disease by  loosening the fit of the teeth in their sockets by rocking them back and forth (like loosening a fence post by rocking it) and by bending the teeth from side to side and thereby causing the brittle enamel just above the gumline to pop out and create little defects known as abfractions on the cheek sides of the teeth at the gumline.   By covering all the upper teeth and contacting all the lower teeth with inclines carefully sculpted to create wide distribution of bite forces, stabilization appliances prevent nocturnal grinding or clenching from causing abfractions or gum problems. The contours of the bite surface on a stabilization appliance are designed to provide even simultaneous contact of the teeth over a broad area centrally.  Such a bite surface minimizes laterally directed forces on the teeth and stabilizes the positions of the teeth over time.  Maintaining a stable alignment of the teeth protects them from the traumatic forces which can injure a tooth if it drifts into a position where it no longer shares bite forces with other teeth in group function. 

 

Stabilization appliances can protect the TMJs by relieving them of compressive forces, redirecting the vector of biting forces between the lower jawbone and the skull at the TMJs, or protecting the vulnerable retrodiskal tissues from hyper‐retrusion of the condyle. In many cases they work by simply getting you “off” your TMJs during nocturnal clenching or grinding. For example, if you keep walking on a damaged ankle, it won’t get better, and your leg muscles will automatically tighten up to produce a limp in an attempt to protect the damaged ankle. When you lie in bed for 8 hours, you’re off your ankle, and it can undergo a natural healing response. You don’t have a way to get off your TMJs.  Clenching and grinding keep the jaw system active during sleep, especially during transitions between sleep stages.

 

Upper stabilization appliances have anti‐retrusion ramps that are designed to protect the retrodiskal tissues. Studies have shown that these retrodiskal tissues are chronically bruised in most TMJ disorder patients. Anti‐retrusion ramps protect the retrodiskal tissues by ensuring that they cannot be impacted by the condyles at the rear end of the natural range of movement of the lower jawbone.  These anti‐retrusion ramps do not hold your lower jawbone any further forward than its natural bracing position, (they are not pull‐forward ramps). They simple prevent your lower jawbone from dropping back further than the natural bracing position during sleep when the combination of gravity and clenching or grinding against a TMJ with a dislocated disk allows the condyle of the affected TMJ to keep bruising the retrodiskal tissues. Anti‐retrusion ramps are often located behind the front teeth and occasionally located behind the back teeth if there is space available. 

 

The angle of the anti‐retrusion ramps determines the degree of joint protection provided by the appliance. Steep ramps are used when more joint protection is needed, such as when a TMJ is arthritic or inflamed. If the anti‐retrusion ramps are functioning correctly in a person with an inflamed TMJ, biting forcefully against the ramps will produce a relief of the pain which is experienced by biting forcefully against the natural teeth. Shallower ramps are used when the problem is located more in the jaw muscles than in the TMJs.   Muscles benefit from a wide range of movement. 

 

The jaw muscles are always involved in TMJ disorders, because muscles are responding organs. The state of tension in the muscles which cross any joint is controlled by the health of that joint. When a joint is inflamed, the involved muscles tighten at rest in an automatic bracing mode designed to protect injured joints. There are two TMJs but they are both connected to the same bone, so they are wired as if they were one joint. When one TMJ is inflamed, the jaw muscles on both sides tighten at rest. When a TMJ problem has gone on for a long time and the jaw muscles have been held tight for a long time, they lose resting length which causes them to shorten and impairs their resting circulation. They then need to be stretched out to restore their resting length. 

 

Stabilization appliances stretch out chronically tight jaw muscles by creating a tall and stable bite surface for the jaw muscles to clench or grind against during sleep. The forceful contractions against a tall platform stretch the jaw muscles, probably by relative sliding of adjacent serial sarcomeres. Jaw muscles can also be stretched out by various physical therapy measures, such as icing the side of the face while biting on a wine cork or another type of thick block placed between the front teeth. 

 

Appliances which are too thick can exacerbate TMJ disorders by adversely affecting tongue posture. Since the tongue has no bone of its own, its base of operation is the lower jawbone and the little hyoid bone which hangs from the lower jawbone. Anything that causes retrusion of the tongue causes retrusion of the lower jawbone. Studies have shown that placing a block of acrylic in the palates of growing monkeys caused them to grow long narrow faces because it forced the tongue to acquire a lower and more retrusive resting posture which forced the lower jawbone to also acquire a lower and more retrusive resting posture. Dental labs are generally more concerned with breakage than with tongue posture, so almost all appliances made by commercial dental labs have unnecessary bulk which causes retrusion of the postures of the tongue and lower jawbone and can thereby exacerbate the same problem we are trying to solve. 

 

Appliances which fit too tightly, especially around the front teeth, are another problem with TMJ appliances made by commercial dental labs. Plastics all shrink when they set. The upper dental arch is generally horseshoe shaped, so the shrinkage of plastic in a dental appliance covering the upper dental arch squeezes the front teeth inward. Recently some dental manufacturers have responded to the complaints of patients by manufacturing a plastic that can be easily softened by heat. The patient is instructed to run the appliance in hot water just before placing it in the mouth. This prevents the feeling of extreme tightness when first placing the appliance, but the appliance still squeezes the front teeth out of their natural rest positions and into a retrusive position all night long – then the teeth rebound every day. Such shifting back and forth is not good for the teeth.  Eventually the teeth shift backward to fit the appliance, and it will no longer feel so tight, however such backward shifting of the upper front teeth forces the lower jawbone to permanently acquire a more backward shifted posture, the same problem which often causes TMJ disorder conditions in the first place.

 

Temporary stabilization appliances, made at chairside on the first appointment, are a good diagnostic tool for people who want to find out if their symptoms are due to a TMJ disorder. They are usually used for people who have serious symptoms, such as severe headache or ear problems (dizziness, tinnitus, subjective hearing loss, or ear pain) and no other signs of a TMJ disorder.  A stabilization appliance may not be the best appliance for the patient, but if the temporary stabilization appliance has no effect on the headache or the ear problems, these symptoms are probably caused by something else.

 

Adjustments are only needed if the appliance is not just right for your condition in the first place.  In designing the appliance, Dr. Summer makes a number of judgement calls regarding the angle and height of the contours.  If the appliance does not provide sufficient relief, your experience with the wearing the appliance will inform Dr. Summer regarding how the appliance needs to be changed to provide better relief.  However there is no need to schedule regular adjustments.

 

Temporary stabilization appliances cost $175 which includes one follow-up visit to review the results.  The follow-up visit is useful because learning how  the temporary stabilization appliance affected your condition can help determine the best appliance or bite treatment for long term relief.

 

Custom stabilization appliances cost $850, which also includes one follow-up visit to review the results.  We make a number of judgement calls in choosing stabilization appliance characteristics, like the height and angle of the ramps and the contours of the bite surface.  If at first you don't get the relief we expect, your experience with wearing the appliance for a week or two will usually provide the information needed to better customize your appliance to best fit your needs.