|
What is TMJ, or TMD, or CMD?
CMD as we refer to it, is a syndrome created by the dysfunction of the lower jaw as it relates to the upper jaw (thus the term CranioMandibular Dysfunction). The significant elements in the system are the upper and lower jaws, the jaw joints (TemporoMandibular Joints), the teeth, and the related muscles.
The Symptoms
Here lies the complexity of this syndrome. Signs and symptoms are many and varied. Few two people have the same ones. Many of the signs and symptoms are distant, and therefore thought to be unrelated. Only recently have some of the relationships been established that have helped to identify the true cause of the problem. There are four groups of signs and symptoms that are commonly reported.
- Joint symptoms, like clicking or popping or pain in the joint(s).
- Related muscle symptoms, like facial pain and headaches. CMD is probably the most common cause of headaches, but rarely mentioned.
- Tooth related symptoms, like sensitivity, receding gums, bruxing, and clenching.
- Skeletal symptoms, like neck and shoulder pain, ear pain, back pain, and poor posture.
The Causes
The cause of the symptoms is a misalignment in the bite between the upper and lower teeth which forces the jaw out of normal position. As the muscles and joints attempt to compensate, the symptoms develop. If we look back to see why we have a bad bite, growth and development influences like breathing problems and thumbsucking may have played a role. Trauma like a car accident can have an impact as well. Understanding these causes is helping doctors to provide care that will prevent these problems in the future. For example, orthodontic treatment usually always changes the bite. Only with the understanding of how vital the role of the bite is are we learning to provide orthodontic treatment that will prevent these problems in the future. Other factors like stress, also play a role by intensifying the effects produced by the dysfunction.
The Diagnosis
The diagnostic regimen utilized to pinpoint the problem is extensive. A comprehensive examination, medical history, X-rays of the joints, and models of the teeth. More recently, computer technology is providing joint vibration analysis, muscle function analysis, and jaw motion tracking. These new tools are playing an important role in removing the subjective elements in our diagnostic efforts.
The Treatment
Treatment usually involves two phases. The first is to construct an "Orthotic", which is a retainer-like appliance that is worn over the lower teeth. The purpose of this appliance is to "re-align" the lower jaw such that the stresses on the joints and muscles are relieved. The second phase of treatment involves altering the teeth such that the bite is correct without the orthotic. This can involve orthodontic treatment, restorative treatment, or some combination of both. Sometimes only an adjustment to the biting surfaces of the teeth is required to effect the change.
The Role of Stress
Everybody has stress, and it gets blamed for many of the symptoms of craniomandibular dysfunction. The fact is that the craniomandibular dysfunction is more the cause of the stress than the other way around. Stress can be a factor by aggravating a condition, but it is not the cause of headaches, or any of the other signs and symptoms of craniomandibular dysfunction.
|