Backscattered electron (BE) microscopy is being used increasingly as a technique to study the dissolution of dental enamel because of its high resolution and relatively easy sample preparation. Subsurface details such as striae of Retzius, cross-striations and prism microstructure have been observed with a resolution better than 0.1 micrometers using this technique. Since BE images of demineralized enamel appear very similar to microradiography images, it is tempting to interpret them in a similar fashion. We attempt to show that the interpretation of BE images is not straightforward because enamel is not a homogeneous one-phase material, but a two-component composite material consisting of variable amounts of apatite mineral and organic matter. During re- and demineralization, other calcium phosphate phases may precipitate to further complicate the interpretation of the images. BE images of partially demineralized enamel are affected by local variations in the protein / mineral ratio and also by the reprecipitation of other calcium phosphate phases. BE images are not mineral density maps, but are mean atomic number maps.
Nelson, D. G. A.
"Backscattered Electron Imaging of Partially-Demineralized Enamel,"
Scanning Microscopy: Vol. 4
, Article 4.
Available at: https://digitalcommons.usu.edu/microscopy/vol4/iss1/4