A morphological study was done of Tomes' process, the organic matrix and the hydroxyapatite crystals of enamel. The membrane of Tomes' process where secretion of rod and interrod material occurs is extensively infolded. The interrod secretion site extends circumferentially around the ameloblast and granules fuse with deep membrane infoldings. The infoldings associated with secretion sites can be abolished by injecting vinblastine. Newly secreted enamel proteins do not accumulate extracellularly. So-called "stippled material" is an artifact of fixation and results from degradation of previously calcified enamel. Simultaneous visualization of the organic matrix and hydroxyapatite crystals is not possible because the aqueous stains needed to reveal the organic matrix dissolve the young enamel crystals. Osmium tetroxide, however, protects against beam damage and dissolution by water. When visualized separately the organic matrix seems to be contained within the space occupied by the crystal. Using stereo electron microscopy, crystals appear as thin flat ribbons. Images previously described as hexagonal cross-cut crystals are due to visualizing a three-dimensional structure in two dimensions.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.68645 |
| Date | January 1982 |
| Creators | Nanci, Antonio. |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Doctor of Philosophy (Department of Anatomy) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 000156345, proquestno: AAINK60931, Theses scanned by UMI/ProQuest. |
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