Sensory innervation of temporomandibular joint disk.

PURPOSE To investigate the nerve endings of the adult temporomandibular joint disk, in particular the presence and configuration of the sensory nerve endings by silver staining and electron microscopy. METHODS 20 cadaveric temporomandibular joints impregnated with silver stain were studied using an optical microscope; 2 other joints were studied using a transmission electron microscope. RESULTS Free nerve endings were found in the disk parenchyma of all joints. Golgi-Mazzoni corpuscles, Ruffini corpuscles, and articular corpuscles were also observed as sensory nerve end organs. Myelinated and nonmyelinated nerve fibres were visualised in the disk parenchyma using the transmission electron microscope. CONCLUSION Free nerve endings and sensory nerve end organs are present in the disk parenchyma of the human temporomandibular joint and are associated with sensation and proprioception, just as they are in the acetabular labrum, glenoid labrum, triangular fibrocartilage complex, and meniscus.