Determination of Hydroxyapatite Crystallite Size in Human Dental Enamel by Dark-Field Electron Microscopy

Abstract

Ion-thinned longitudinal sections of a third molar were observed by bright- and dark-field electron microscopy. In bright field, the hydroxyapatite crystallites in enamel appeared as long rods, but, when observed in dark field, the crystallites were rectangular, with a mean length of 321 A.

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