Elastic fibers in the human temporo-mandibular joint disc

The elastic fiber content of 12 articular discs, removed from 12 patients w ith complete anterior or medio-anterior disc displacement, nas examined. Fi ght to 12 sagittal sections (3 mu m each) were acquired for each disc and s tained with modified resorcin-fuchsin for visualization of elastic fibers. The program "CUE-2 image Analyzer Morphometry" digitized all sections with 800 x magnification, calculated the elastic fiber content and reconstructed it 3-dimensionally. The calculated volume density of the entire disc was a mean x(tot)=0.339+/-0.060% of the total tissue. The highest fiber content of 2-4% was found in the posterior area at the transition to the bilaminar zone. 61% of the elastic fibers were located in the bilaminar zone, 10% in the posterior, 2% in the intermediary and 26% in the anterior band. There u ere substantially more fibers in the cranial part of the posterior region and at the medial edge as compared to the mean fiber distribution of the po sterior band and the bilaminar zone. A third of these fibers were found in the inferior layer. particularly in the lateral part. Exactly the opposite fiber distribution was seen in the anterior band, The fibers frequently app eared in the caudal layer, especially in the lateral periphery, but there a ere fewer fibers in the medial cranial laver.