Figure 2.
Scanning electron microscopy images of acid-etched enamel cut in a direction perpendicular to enamel rods at ×1K (A), ×20K (B), and the mineral layer deposited on acid-etched enamel cut in a direction perpendicular to the enamel rods following a 20-h exposure to the inorganic pyrophosphate (PPi)–stabilized supersaturated calcium phosphate (CaP) solution in the absence (C, at ×1K and D, at ×20K) and in the presence (E, at ×1K and F, at ×20K) of 0.04 mg/mL leucine-rich amelogenin peptide (LRAP). In the absence of LRAP (C and D), large randomly arranged plate-like crystals formed on the enamel surface, while in the presence of LRAP (E and F), the regenerated layer was composed of a dense packing of small needle-like crystals in somewhat parallel arrangement and reflected to a very significant degree the typical enamel prismatic pattern of the underlying original enamel surface.