Electron microscope study of defect zones in dental enamel

Abstract

A comparative study of synthetic and natural apatite has been made by means of high-resolution transmission electron microscopy, with the aim of elucidating structural differences between the two materials. Natural dental apatite is distinguished by the presence of mineral-deficient zones, which are likely centers for artificial etchant attack. The nature of these zones has been examined by the technique of preferential heavy-metal staining. This technique, in conjunction with the standard interpretation of lattice-image contrast, leads to the conclusion that these are naturally occurring calcium-deficient zones and are not the result of either beam damage or mechanical defect.