Стоматологический факультет temporomandibular joints

Any dysfunction of the muscles may cause the teeth to occlude (bite) with each other incorrectly; if teeth are traumatized by this, they may become sensitive, demonstrating one of the many interplays between muscle, joint, and tooth.

This is arguably the most complex set of joints in the human body. Unlike typical finger or vertebral junctions, each TMJ actually has two joints, which allow it to both rotate and to translate (slide). With use, it is common to see wear of both the bone and cartilage components of it. Clicking is common, as are popping motions and deviations in the movements of the joint. It is considered a TMJ disorder when pain is involved.

In a healthy joint, the surfaces in contact with one another (bone and cartilage) do not have any receptors to transmit the feeling of pain. The pain therefore originates from one of the surrounding soft tissues. When receptors from one of these areas are triggered, the pain causes a reflex to limit the mandible's movement. Furthermore, inflammation of the joints can cause constant pain, even without movement of the jaw.

Due to close proximity of the ear to the temporomandibular joint, TMJ pain can often be confused with ear pain. The pain may be referred in around half of all patients and experienced as otalgia (earache). Conversely, TMD is an important possible cause of secondary otalgia. Treatment of TMD may then significantly reduce symptoms of otalgia and tinnitus, as well as atypical facial pain. Despite some of these findings, some researchers question whether TMD therapy can reduce symptoms in the ear, and there is currently an ongoing debate to settle the controversy.

The dysfunction involved is most often in regards to the relationship between the condyle of the mandible and the disc. The sounds produced by this dysfunction are usually described as a "click" or a "pop" when a single sound is heard and as "crepitation" or "crepitus" when there are multiple, rough sounds [citation needed]

Teeth

Disorders of the teeth can contribute to TMJ disfunction. Impaired tooth mobility and tooth loss can be caused by destruction of the supporting bone and by heavy forces being placed on teeth. The movement of the teeth affects how they contact one another when the mouth closes, and the overall relationship between the teeth, muscles, and joints can be altered. Pulpitis, inflammation of the dental pulp, is another symptom that may result from excessive surface erosion. Maybe the most important factor is the way the teeth meet together: the equilibration of forces of mastication and therefore the displacements of the condyle.

Precipitating factors

There are many external factors that place undue strain on the TMJ. These include but are not limited to the following:

Temporomandibular joint disorder (TMJD, TMJ or TMD), or TMJ syndrome, is an umbrella term covering acute or chronic inflammation of the temporomandibular joint, which connects the mandible to the skull. The disorder and resultant dysfunction can result in significant pain and impairment. Because the disorder transcends the boundaries between several health-care disciplines — in particular, dentistry, neurology, physical therapy, and psychology — there are a variety of treatment approaches.

The temporomandibular joint is susceptible to many of the conditions that affect other joints in the body, including ankylosis, arthritis, trauma, dislocations, developmental anomalies, and neoplasia.