One in eight Americans suffers from headaches (Pain, Academy of General Dentistry). As much as eighty percent of all headaches are caused by muscle tension, which may be related to bite problems. Headaches also can be caused by clenching jaw muscles for long periods of time. Signs that may indicate a headache from a dental origin include:
Pain behind the eyes
Sore jaw muscles or "tired" muscles upon awaking
Clicking or popping jaw joints
Head and/or scalp is painful to the touch
Earaches or ringing
Neck, shoulder or back pain
There are a variety of treatments that will help alleviate orofacial symptoms. One device is called an orthotic, or splint, that is worn over the teeth until the bite can be stabilized. Often permanent correction is practiced such as reshaping teeth (coronoplasty), building crowns or bonding, orthodontics, or surgery that installs a permanent appliance for the mouth. However, unlike the splint, these irreversible procedures lack sound scientific evidence of providing any true benefit. This paper explains the Temporomandibular disorder (TMD) and the known advantages and disadvantages of treatment.
TMDs refer to a variety of conditions causing pain in the temporomandibular joint (TMJ) (Temporomandibular disorders, Mayo Clinic). The TMJ is the hinge joint on each side of the head where the lower jawbone (mandible) joins with the temporal bone of your skull. The bony surfaces of the TMJ are covered with cartilage and separated by a small disk, which prevents them from rubbing against each other. The muscles that enable the mouth to open and close stabilize this joint. There are many causes of tenderness in the TMJ such as wear and tear, arthritic inflammation, injury, stress, and poorly fitting braces or other dental appliances. The pain associated with TMD can vary from minor to severe and he condition may be either temporary or chronic. About ten million Americans experience some form of chronic facial pain. Of these, seven million people experience pain associated with their chewing muscles or with their TMJ or with both.
The diagnosis procedures for TMD should include a collection of functional data such as models of the mouth and inter-jaw records which can then be placed on a jaw simulator (articulator). This lets the dentist determine how the teeth and joints are related to each other and how then function without the influence of the jaw muscles. There should also be a muscle palpation examination, measurement of jaw movements and slide photographs of the teeth in their functional relationships. X-rays will show "ball and socket" positions at various openings and show if there are any bony changes such as arthritis.
If TMD is diagnosed, the first treatment step should be a removable orthotic device also known as a splint, which will cover the biting surfaces of the upper teeth (McBride). It is initially adjusted so that all the lower teeth hit it evenly to start taking the pressure off the jaw joints. The patient must wear the device full time except for removal during oral hygiene and eat only soft foods at first. So, the orthotic device requires a major commitment from the patient. As the jaw joints become healthier, the lower teeth will begin to hit the orthotic differently, and the orthotic will therefore require periodic adjustments. Another disadvantage of the orthotic wear is that the new positioning of the joints can only by maintained by continuing orthotic wear.
Despite the obvious disadvantages of orthotic wear, it should always be the first treatment step for TMD for several reasons (McBride):
It is necessary to develop stable, healthy jaw joints before commencing other types of dental treatment. Because the joints and teeth have an influence on each other, the final treatment of the biting surfaces of the teeth should be dictated by joints having been treated to a healthy "end point."
It is important to determine whether the symptoms are really due to the bite discrepancy before moving to more invasive procedures. Many factors can other than bite problems can contribute to the symptoms such as physical and emotional health, muscle tension caused by stress, general attitude and habits.
Orthotic wear provides a reversible, non-invasive treatment to test the diagnosis. If orthotic treatment is not successful, other treatments can be instituted such as Biofeedback, Stress Management, and Acupuncture.
Some patients may find that after the resolution of their symptoms, night time orthotic wear only will either eliminate the symptoms or lessen them enough to be adequate without further treatment (McBride). Further dental treatment can consist of any one or a combination of four different types:
Equilibration (re-shaping of teeth biting surfaces).
Restorative treatment such as crowns, bonding etc.
Jaw discrepancy-orthognathic (jaw repositioning) surgery
But, there is considerable debate on whether or not any of these treatments are really effective. The National Institute of Dental and Carniofacial Research (Temporomandibular disorders (TMD) warns that irreversible treatments are of little value and may make the problem worse including orthodontics to change the bite; restorative dentistry, which uses crown and bridge work to balance the bite; and occlusal adjustment, grinding down teeth to bring the bite into balance.
Research studies support the recommendations of The National Institute of Dental and Carniofacial Research. One study in 1999 concluded that splints may be of some benefit in the treatment of TMD, but that the evidence for the use of occlusal adjustment is lacking (Forssell, Kalso, Koskela, Vehmanen, Puukka, and Alanen, 1999). This study included fourteen trials on splint therapy and four on occlusal adjustment. Splint therapy was found superior to three, and comparable to twelve control treatments, and superior or comparable to four passive controls, respectively. Occlusal adjustment was found comparable to two and inferior to one control treatment and comparable to passive control in one study. But, the researchers admit that because of the methodological problems, only suggestive conclusions can be drawn. The overall quality of the trials was fairly low because of shortcomings such as inadequate blinding, small sample sizes, short follow-up times, great diversity of outcome measures and numerous control treatments, some of unknown effectiveness.
A more recent review of experimental evidence in 2001 concluded that facts are not convincing enough to support the performance of occlusal therapy as a general method for treating a nonacute TMD, bruxim or headache (Tsykiyama, Baba and Clark, 2001. The review included eleven research experiments. Three evaluated the relationship between occlusal adjustment and bruxism; six evaluated occlusal adjustment therapy as a treatment for patients with primary TMDs and one experiment looked at occlusal adjustment effect on headache/TMD symptoms; another looked at its effect on chronic neck pain. The data from these experiments did not demonstrate elevated therapeutic efficacy for occlusal adjustment over the control or the contrasting therapy.
The National Institute of Dental and Carniofacial Research (Temporomandibular disorders (TMD)) advises patients to avoid surgical treatments where possible. This is because scientists have discovered that surgical replacement of jaw joints with artificial implants may cause sever pain and permanent jaw damage. Also, some of these devices may not function properly or may break apart in the jaw over time. As an example, the Food and Drug Administration had to recall the artificial jaw joint implant manufactured by Vitek after it broke down and damaged surrounding bone.
Neither the American Dental Association nor the American Medical Association even recognizes the treatment of TMD as a specialty (TMJ diseases & disorders, The TMJ Association). This means that there are no established standard criteria for dental/medical school education. Often times, treatments are based largely on professional beliefs, not scientific evidence. This explains why many dentists go beyond the orthotic device to treat TMDs even though no scientific evidence exists to support such decisions and most respected health organizations counsel against equilibration, restorative treatments, orthodontics and more drastic invasive surgery techniques.