Journal of Dental Research, Vol 80, 1560-1564, Copyright © 2001 by International & American Associations for Dental Research Online Journals
High-resolution electron microscopy of the crystallites of fossil enamels obtained from various geological ages
M. Kakei, H. Nakahara, M. Kumegawa, H. Mishima and Y. Kozawa
1st Dept. of Oral Anatomy, School of Dentistry, Meikai University, Sakado, Saitama, Japan. m-kakei@dent.meikai.ac.jp
To elucidate the stability of the central dark line (CDL) in biologically
induced hydroxyapatite crystals, we examined the diagenetic changes on the
microstructures of the crystallites during the course of fossilization.
Using transmission electron microscopy, we investigated the enamel
crystallites of fossil animals of various geological ages ranging from
Pleistocene to Cretaceous. Electron micrographs indicated that the
microstructures and lattice images of each crystallite in fossil enamels
were well-preserved regardless of the thickness of the enamel layer, and
the presence of CDLs in fossil enamel crystals was also confirmed. The
results indicated that the microstructure of hydroxyapatite crystals
containing lattice images of CDLs appear stable during long geological
periods. In addition, we conclude that the existence of lattice images in
apatite with CDLs may be an indicator for the assessment of the evolution
of dental enamel from fossil remains.
