Dental cosmos . cell is an individual, and but exceptionally in connection withits neighbor. With us a cell is a lump of protoplasm, in which 758 THE DENTAL COSMOS. the living matter is stored up in different shapes. The glisteningglobules of small size, having arisen from the protoplasm of theoriginal columnar epithelia of the enamel-organ, represent a juvenilecondition of living matter in its most compact aggregation. The medullary corpuscles, sprung from the ameloblasts, show-only a delicate reticulum of living matter, being ready for immedi-ate transformation into basis-substance and calci
Dental cosmos . cell is an individual, and but exceptionally in connection withits neighbor. With us a cell is a lump of protoplasm, in which 758 THE DENTAL COSMOS. the living matter is stored up in different shapes. The glisteningglobules of small size, having arisen from the protoplasm of theoriginal columnar epithelia of the enamel-organ, represent a juvenilecondition of living matter in its most compact aggregation. The medullary corpuscles, sprung from the ameloblasts, show-only a delicate reticulum of living matter, being ready for immedi-ate transformation into basis-substance and calcification. Betweenthese extreme stages stand the ameloblasts, with their vesicularnuclei, and a markedly heavy reticulum of living matter in theirinterior. The indifferent corpuscles, serving to supply additions tothe ameloblasts, exhibit all intermediate stages between small,globular, glossy and compact globules up to distinctly nucleatedprotoplasmic lumps. Whatever the size and shape of such lumps Fig. 3. M2 ED. Ameldblatte beginning the formation of enamel; from human foetou, six months.—D, border of newly-formeddentine. E, first trace of iorming enamel. A, row of ameloblasts. M1, m<dullary corpuscles forlestitution of ameloblasts. M- medullary corpuscles just previous to tbeir infiltration with , fibrous connective tissue, the so-called intermediate layer. X 1000. may be, they are invariably connected with one another by meansof delicate offshoots, which vary greatly in thickness and in theircourse. Each ameloblast sends offshoots toward the dentine ingreat numbers, known as Tomes processes. They also run upwardtoward the intermediate layer, and laterally for the immediateunion of neighboring ameloblasts. (See Fig. 3.) Broad and clumsy offshoots, such as depicted by Tomes and Wal-deyer, are visible only upon torn and teased ameloblasts. So long asthese bodies are in situ the offshoots are always delicate, and visiblewith higher powers of the microscope only,
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Keywords: ., bookauthor, bookcentury1800, bookdecade1880, booksubjectdentistry
