A text-book of dental histology and embryology, including laboratory directions . comparativelywide in the apical portion, the cords becoming scarcer as theapex of the root is approached, but the author has seen themin sections from the apical third. A binocular microscope was used to obtain a true concep-tion of the way in which these cords wind in and out amongthe bundles of fibers. The cords show a marked tendencyto run out into the membrane and loop back (Fig. 240),coming very close to the surface of the cementum. 308 THE PERIDENTAL MEMBRANE The ends of the loops toward the cementum often
A text-book of dental histology and embryology, including laboratory directions . comparativelywide in the apical portion, the cords becoming scarcer as theapex of the root is approached, but the author has seen themin sections from the apical third. A binocular microscope was used to obtain a true concep-tion of the way in which these cords wind in and out amongthe bundles of fibers. The cords show a marked tendencyto run out into the membrane and loop back (Fig. 240),coming very close to the surface of the cementum. 308 THE PERIDENTAL MEMBRANE The ends of the loops toward the cementum often showenlargements which in some cases apparently lie directlyin contact with the cementum (Figs. 241 and 242). Theseenlargements next to the cementum are shown in Fig. 240. The Arrangement of the Cells.—There is no definite arrange-ment of the cells in these cords. In some places there will bea ring of irregular polyhedral or rounded cells which almostexactly resemble a simple tubular gland. In other placesthere is a pretty definite outer ring of cells and a central Fig. 237. Diagram of glands of peridental membrane. (Black.) mass enclosed by them. The cells are made up of granularcytoplasm, each containing an ovoid nucleus that is rich inchromatin. The author has spent much time attemptingto work out the relation of these cords to the epitheliumlining the gingival space, thinking that possibly they openinto it. In a few places structures appearing very muchlike a duct have been seen, as shown in Fig. 244, but theyare apparently only unusually large cords. There is noregularity in places where they are found, and no con- DISTRIBUTION Fig. 238 309
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectteeth, bookyear1912
