General and dental pathology with special reference to etiology and pathologic anatomy; a treatise for students and practitioners . )y the author show the tendency towardparallelism of the rods on the axial surfaces, but, on the otherhand, do not show many rods traceable uninterruptedly fromwithin to the free surface of the enamel (Fig. 91). Woyes: Dental Histology and Embryology, Philadelphia, Lea & Febiger. ENAMEL, DENTIN, AND CEMENTUM 221 Another peculiarity of enamel, within the bounds of nor-mality arc the bands of Betzius. These are better seen upon ex-amination with a low-power objectiv
General and dental pathology with special reference to etiology and pathologic anatomy; a treatise for students and practitioners . )y the author show the tendency towardparallelism of the rods on the axial surfaces, but, on the otherhand, do not show many rods traceable uninterruptedly fromwithin to the free surface of the enamel (Fig. 91). Woyes: Dental Histology and Embryology, Philadelphia, Lea & Febiger. ENAMEL, DENTIN, AND CEMENTUM 221 Another peculiarity of enamel, within the bounds of nor-mality arc the bands of Betzius. These are better seen upon ex-amination with a low-power objective and appear as brownishstriations which mark the beginning and completion of the cal-cification of sections of enamel structure. They are the boundarylines between calcification installments, and hence have been ap-propriately named by the descriptive term incremental Inns. b Fig. 91.—Ground section. Dentoenamel junction. The character of the granularlayer of Tomes is unusually well shown. The hearing which this laver has upon theprogress of caries should not be overlooked. This section also shows the tendency atparallelism of the enamel rods; a, a, enamel; , dentin; c, c, granular layer. (Noyes). The portions of enamel included between the dento-enamel junction and a hand of Retzius, and between the bandsthemselves, represent synchronous calcification installments (). These bands of brownish color, when viewed under a lowor high amplification, run obliquely across the lengths of theenamel rods from the dentoenamel junction on one side to the 222 DENTAL PATHOLOGY dentoenamel junction on the opposite (from mesial to distal sur-faces) in the incisal region and in the cusps of bicuspids andmolars. Beyond these regions they run from the dentoenameljunction to the surface of the enamel. They mark the strata ofenamel in the order of their calcificat
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectpathology, bookyear19
