The Organic Elements of the Enamel

Abstract

The organic framework of adult human teeth was isolated by a low-temp, de-mineralization in 5% trichloro-acetic acid and examined through binocular observation, microdissection, smears, and paraffin sections. In contrast to the homogeneous external portion, with its wide and straight-running prisms, the internal organic frame-work of the enamel exhibited densely packed prism sheaths arranged in longitudinal corrugated segments. Viewed in transversely cut paraffin sections the central part of these denser segments were found to be responsible for the appearance of the so-called tufts. Viewed in a longitudinal plane the corrugated patter of the organic framework reflected itself in grossly visible Schreger''s bands, indicating that these bands are independent of the pattern or degree of calcification. It is suggested that the morph. of the external dentin surface, which embryologically precedes the formation of enamel, may have a bearing on this pattern of the organic framework in 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.