The temporomandibular joint is one of the most complex joints in the body: it opens and closes in a circular motion around a fixed axis, moves forward, down, and back, and moves sideways from one side to the other. The temporomandibular joint can apply tremendous pressure during chewing, depending on the position and health of the upper and lower teeth, and the teeth act as shock absorbers to prevent it from closing too much. The temporomandibular joint contains a piece of dense fibrous tissue called the articular disc. The articular disc acts as a cushion between the skull and the lower jawbone, preventing them from rubbing directly against each other.