1999 Volume 19 Issue 4 Pages 361-374
Collagen fibrils and elastic fibers contained in the normal retrodiscal tissue of the temporomandibular joint (TMJ) were studied with emphasis on the visualization of their three-dimensional organization using a scanning electron microscope. The retrodiscal tissues were taken from human adult cadavers ranging from 56 to 78 years old.
The main fibril bundles seen in the posterior band of TMJ disks presented a linear or wavy appearance and ran anteroposteriorly in the vicinity of the retrodiscal tissue. These bundles became less compact at the posterior band-retrodiscal tissue junction and the anterior border of the retrodiscal tissue. There was a stack of lamella composed of fibril bundles that predominantly ran anteroposteriorly in the uppermost layer of the retrodiscal tissue. The fibril lamellas passing mediolaterally, and a network of elastic fibers, were seen in the layer below the uppermost surface. In an intermediate layer of retrodiscal tissue, linear, lamellar, wavy or spiral bundles of fibrils were irregularly and sparsely arranged. The deepest layer contained a stack of lamella composed of anteroposteriorly, mediolaterally, or irregularly arranged fibril bundles. The organization of the fibril bundles and elastic fibers seems to provide some elasticity under tensile stress. The retrodiscal tissue is similar to the TMJ disk in this regard, but may exert little resistance to functional pressure because of the spase arrangement of fibrils.
