Temporomandibular disorders, (TMJ
/ TMD), describes a group of diseases that can involve the
jaw joints, the muscles that control jaw movement and the
dental occlusion. TMJ / TMD's are physical disorders arising
from an imbalance in the delicate working relationship of
the jaw and skull with the muscles that move the jaw, as
well as the nervous system associated with these systems.
The imbalance results in muscle fatigue, spasm and /or joint
dysfunction and even changes in the teeth, which in turn
cause a variety of symptoms, unique for each person.
The temporomandibular joint
is the hinge joint that connects the lower jaw, (mandible),
to the temporal bone of the skull, which is immediately
in front of the ear on each side of your head. The joints
are flexible, allowing the jaw to move smoothly up and down
and side to side and enabling you to talk chew, and yawn.
Muscles attached to the surrounding jaw joints control the
position and movement of the jaw.
TMJ / TMD joint stystem is unique in many ways. The left
and right joints must coordinate, working at the same time
for the jaw to move. While the opening, lateral and forward
movements of the jaw are controlled by the shape of the
bones and are a function of muscles and ligaments, the closing
end-point of the jaw movement is controlled by the coming
together of the teeth – the bite or occlusion. No
other joint in the body has such a rigid end-point limit.
The proper, healthy function
of the TMJ / TMD systme requires normal structure and function
of all the component parts, including muscles, nervous sytem,
ligaments, joint, (bones, discs and connecting tissues),
and the dental occlusion.