title: Backscattered electron imaging of partially-demineralized enamel.
abstract: 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.
authors.affiliation: Procter & Gamble Co., Cincinnati, Ohio 45239.
authors.forename: D G
authors.initials: DG
authors.lastname: Nelson
mesh_terms: D003743:Dental Enamel / Q000378:metabolism*; D006801:Humans; D008433:Mathematics; D008855:Microscopy, Electron, Scanning / Q000379:methods*; D008903:Minerals / Q000378:metabolism
chemical_list: D008903:Minerals