Neural elements in the human temporomandibular articular disc.

The purpose of this study was to determine the presence and describe the location of neural elements in the articular disc of the human temporomandibular joint. Six articular discs were obtained from three adult human subjects at autopsy. Four discs were cut into segments of known anterior-posterior orientation. The remaining two were processed intact. All tissues were stained in bulk with gold chloride, and frozen, sectioned on a sliding microtome at 70 to 100 microns, mounted on slides, dehydrated, and coverslipped. Nerve fibers were seen penetrating the discs from the pericapsular connective tissue. Structures resembling Ruffini endings, Pacinian corpuscles, and Golgi tendon organs were identified in the pericapsular connective tissue and within the disc. The population density of neural elements was the greatest at the periphery of the disc and progressively decreased towards the center, which was essentially devoid of them. The concentration of neural elements appeared to be greater at the anterior and posterior margins of the disc, with the greatest concentration being posteriorly. These findings support the theory that afferent nerves may arise from neural elements within the disc.