Fibro-Arehitectonics of Human Temporomandibular Joint

Abstract

1. This study has been done with following three methods to elucidate the fibro-architecture of human temporomandibular joint, (a) Whole joint was embedded in Histosec (Merck) and the sections were made by Reichert-Jung Heavy-duty Mikrotome K type with tungsten knife and stained, (b) Small part of joint was sectioned and embedded in styrene and sections were made into requisite direction with glass knife and stained. Then (c) after block (the whole) staining has been done, the film-preparation (Häutchen-präparat) of synovial membrane has been made. 2. Structure of the disc in the temporomandibular joint by the film-preparation and fibro-architecture depending on passive movement of synovial membrane have been reported, (a) Typically stratum synoviale consists of synovial cells, lamina propria synovialis and tela subsynovialis but at the central portion of the disc lamina propria and tela subsynovialis agree with disc fibers. At the peripheral portion of the disc and the part which shifts to articular-cartilage in the peripheral portion lamina propria, tela subsynovialis and disc fibers are present, and lamina propria and tela subsynovialis thicken distinguishably. Especially at the reflection both of them become thickest, (b) Synovial cells become extremely squamous at the part with fibro-cartilage of the disc i. e., at the central portion of the disc but at the part without fibro-cartilage in the peripheral portion of the disc they become cuboidal. 3. Running of the synovial membrane fiber by the film-preparation has been described, (a) Collagen fibers of lamina propria run in concentric circle toward the central portion of the disc, (b) Collagen fibers of tela subsynovialis run radially from the central portion of the disc, (c) Elastic fibers generally run in consentric circle toward the center of the disc but cubic network structure is shown in the anterior extension, bilaminar zone and peripheral of insertion at lateral pterygoid muscle in the medio-peripheral portion of the disc. 4. It was assumed that the structure of the synovial membrane above-mentioned provides temporomandibular joint movement including disc movement caused by mechanic-function. © 1982, Editorial Board of Okajimas Folia Anatomica Japonica. All rights reserved.