Life Sciences Commons^™

Backscattered Electron Imaging Of Partially-Demineralized Enamel, D. G. A. Nelson

Scanning Microscopy

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 …

Recent Uses Of Electron Microscopy In The Study Of Physico-Chemical Processes Affecting The Reactivity Of Synthetic And Biological Apatites, J. D. B. Featherstone, D. G. A. Nelson

Scanning Microscopy

Studies which used scanning electron microscopy (SEM) to investigate subsurface demineralization of dental enamel have recently been well reviewed. The purpose of the present paper was to review several studies, carried out in our laboratories, which have used electron microscopy to examine physicochemical properties of synthetic and biological apatites, to relate these results to previous studies, and to present new data.

Aspects of the ultrastructure of hydroxyapatite and carbonated-apatites have been observed by high resolution transmission electron microscopy, and related to shape and growth of these crystals.

Surface morphologies of discs prepared from precipitated carbonated-apatites and from ceramic carbonated-apatites were …

Tandem Scanning Reflected Light Microscopy: Applications In Clinical Dental Research, Timothy F. Watson, Alan Boyde

Scanning Microscopy

The Tandem Scanning Reflected Light Microscope (TSRLM) enables the investigation of microscopic structures both at and deep to the surface of intact objects. The present paper reviews studies undertaken to determine whether the TSRLM would be usable and useful in the investigation of natural and restorative dental materials in vitro and in vivo.

It was found that the TSRLM could be used to study normal and diseased dental tissues and the new materials which are used to replace lost substance. More importantly, it could be used to characterize the interface between tooth and optically translucent materials in bulk samples, giving …

The Root Surface: An Illustrated Review Of Some Scanning Electron Microscope Studies, Sheila J. Jones

Scanning Microscopy

This review paper highlights how the advent of a new type of surface microscopy in the late 1960s, scanning electron microscopy (SEM), was responsible for a fresh appraisal of the structure of the root surface. Details of the formation, resorption and repair of cementum, all surface phenomena, and the varied relationships and mineralization patterns of the two sets of fibres within cementum - the hall mark of the tissue - could be seen in a way and at a range of magnifications hitherto impossible. The major interpretational advances were made rapidly using secondary electron imaging of anorganic normal, exposed, carious …

Scanning Microscopic Observations On Dental Caries, Sheila J. Jones, Alan Boyde

Scanning Microscopy

This paper presents findings made using special techniques of imaging and/or of specimen preparation to investigate the changes in tooth structure which occur in caries. We have studied both coronal and root caries in enamel, dentine and cementum using scanning electron and confocal scanning optical microscopy.

In preparation for backscattered electron (BSE) imaging in the SEM, teeth were stored in 70% ethanol until further dehydration in ethanol and embedding in polymethylmethacrylate (PMMA). Longitudinally cut surfaces were diamond polished and coated with carbon or silver before BSE imaging. Important changes in the distribution of densities in both enamel and dentine occurred …

The Use Of Scanning Electron Microscopy In Studying Enamel Caries, R. P. Shellis, A. S. Hallsworth

Scanning Microscopy

SEM studies related to carious change in dental enamel are reviewed, and their contribution to understanding the mechanism of formation of the early enamel lesion and of its repair evaluated. SEM has contributed significantly to understanding the mechanism of enamel dissolution at the level of the single crystal. Etching studies have yielded useful information on the effect of enamel structure on the pattern of acid dissolution at the microscopic level and have highlighted the importance of re- precipitation phenomena in modifying the pattern of mineral loss. High-resolution studies have provided interesting quantitative data on changes in crystal size, and also …