THE ORGANIC ELEMENTS OF THE ENAMEL

II. THE ORGANIC FRAMEWORK OF THE INTERNAL PART OF THE ENAMEL, WITH SPECIAL REGARD TO THE ORGANIC BASIC FOR THE SO-CALLED TUFTS AND SCHREGER'S BANDS

¹ Harvard School of Dental Medicine, Boston, Mass.

The internal portion of the organic framework of adult human teeth has been studied, after low-temperature demineralization, by means of binocular observations, microdissection, smears, and paraffin sections.

In contrast to the more homogenous external portion, with its wide and straight-running prism sheaths, the internal organic framework is characterized by densely packed prism sheaths, which are arranged in longitudinal corrugated segments. Viewed in a transverse plane the central part of these denser segments gives rise to the appearance of the so-called tufts, and in a longitudinal plane the corrugated pattern will reflect itself in the grossly visible Schreger's bands.

It is suggested that the morphology of the external dentin surface, which embryologically precede the formation of enamel, may have a bearing upon this pattern of the organic framework of the internal enamel, and may even be reflected in the surface texture of the enamel in cases where a scalloped dentin surface is covered with only a thin shell of enamel.