Neural elements in the human temporomandibular articular disc

Area of Science:

• Neuroscience
• Anatomy
• Histology

Background:

• The human temporomandibular joint (TMJ) articular disc plays a crucial role in joint function.
• Understanding the neural innervation of the TMJ disc is essential for diagnosing and treating TMJ disorders.

Purpose of the Study:

• To investigate the presence and topographical distribution of neural elements within the human TMJ articular disc.
• To identify specific types of neural structures within the disc and surrounding tissues.

Main Methods:

• Autopsy-derived human TMJ articular discs (n=6) were utilized.
• Tissues were processed using gold chloride staining, sectioning (70-100 microns), and microscopic examination.
• Discs were analyzed both intact and sectioned to determine anterior-posterior orientation.

Main Results:

• Nerve fibers were observed entering the articular disc from the pericapsular connective tissue.
• Neural structures resembling Ruffini endings, Pacinian corpuscles, and Golgi tendon organs were identified.
• Neural element density was highest at the disc periphery, decreasing towards the center.
• Concentration was greater at anterior and posterior margins, with the highest density posteriorly.

Conclusions:

• The human TMJ articular disc contains neural elements, including mechanoreceptors.
• Neural innervation is concentrated at the disc periphery and margins, particularly posteriorly.
• These findings support the hypothesis that afferent nerves can originate from neural elements within the TMJ disc.