General and dental pathology with special reference to etiology and pathologic anatomy; a treatise for students and practitioners . in its entirety and extends tothe gingival line. Here it is covered by the unattached gingiva?for a distance of several millimeters. It varies in thickness fromthe gingival line, where it is the thinnest, to the occlusal or in-cising edges where it is the thickest. The increase in thicknessis gradual and particularly Avell marked at such areas of thetooth as arc usually subjected to strong and continued friction andstress during mastication. The greater the stress
General and dental pathology with special reference to etiology and pathologic anatomy; a treatise for students and practitioners . in its entirety and extends tothe gingival line. Here it is covered by the unattached gingiva?for a distance of several millimeters. It varies in thickness fromthe gingival line, where it is the thinnest, to the occlusal or in-cising edges where it is the thickest. The increase in thicknessis gradual and particularly Avell marked at such areas of thetooth as arc usually subjected to strong and continued friction andstress during mastication. The greater the stress to which an areaof crown surface is subjected, the thicker and more resistant willbe the enamel on such an area, not because of any difference inchemical composition, but because of a peculiar arrangement ofthe enamel rods to meet the requirements of great stress. Per-fection in development throughout the enamel is rarely encoun-tered so that in describing this tissue our aim will be to describethe microscopic appearance of an average specimen falling withinthe limits of normality. (Figs. 88 and 89.) 217 218 DENTAL PATHOLOGY. Fig. SS.—Area of normal dentin and enamel, a, dentin; b, enamel; c, c, dentoenameljunction; e, dentinal tubuli; /, series of interglobular spaces faintly reproduced. ENAMEL, DENTIN, AND CEMENT! M 219 The components ! enamel are the enamel rods and the confut-ing or interprismatic substance, the latter being the binding ma-terial which holds the rods together. This substance, like theenamel rods, of ectodermic origin, is a calcified stratified-squa- limus epithelium. The rods are five- or six-sided and from threeand one-half to four and one-half microns in Length. Some ofthe rods may he traced from the dentoenamel junction to thesurface of the crown of the tooth. The cementing substance is
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectpathology, bookyear19
