Transitional structures in lamellar bone
| Autor: | Talmon Arad, Vivi Ziv, Ilana Sabanay, Stephen Weiner, Wolfie Traub |
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| Rok vydání: | 1996 |
| Předmět: |
Male
Histology Materials science Scanning electron microscope Lamellar bone macromolecular substances Fibril Rotation Bone and Bones Specimen Handling Crystal Apatites Transition zone Animals Humans Lamellar structure Child Instrumentation Bone Demineralization Technique Middle Aged Rats Models Structural Microscopy Electron Medical Laboratory Technology Crystallography Electron diffraction Child Preschool Microscopy Electron Scanning Collagen Anatomy |
| Zdroj: | Microscopy Research and Technique. 33:203-213 |
| ISSN: | 1097-0029 1059-910X |
| DOI: | 10.1002/(sici)1097-0029(19960201)33:2<203::aid-jemt10>3.0.co;2-y |
| Popis: | Scanning electron micrographs of fractured surfaces of mineralized bone show a lamellar structure with alternating smooth and rough regions. These have been interpreted as corresponding to two distinct collagen fibril and mineral crystal orientations in a rotated plywood structure. However, in various bones, there are clear indications of transition zones between lamellae in which the fibrils, as well as the plate-like crystals, have intermediate orientations. Strong evidence for intermediate collagen fibril orientations comes from vitrified cryo-sections of demineralized bone. These show zones of fibril segments graded in length between more homogenous regions of fibrils roughly parallel to the specimen section. Evidence for intermediate crystal orientations comes from transmission electron micrographs and electron diffraction patterns of crushed bone fragments. A tentative scheme is presented for an interlamellar transition zone, involving rotation about the collagen fibril axis as well as tilting of this axis parallel to the plane of the interlamellar boundary. Although it may be convenient to think of the structure of lamellar bone as being composed of alternating thick and thin lamellae, it is probably more correct and biologically more relevant to consider one pair of lamellae as the product of a single depositional cycle of varyingly oriented collagen fibrils that subsequently mineralize. © 1996 Wiley-Liss, Inc. |
| Databáze: | OpenAIRE |
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