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Microstructural Features of Carious Human Enamel Imaged with Back-scattered Electrons

Dental Research Unit, Medical Research Council of New Zealand, P. O. Box 27007, Wellington, New Zealand

D.G.A. Nelson

Dental Research Unit, Medical Research Council of New Zealand, P. O. Box 27007, Wellington, New Zealand

We have used back-scattered electrons (BE) in the scanning electron microscope to produce mineral density images of enamel. Flat surfaces of artificially-carious enamel, softened in an intra-oral experiment, and naturally-carious (white spot) enamel were polished to a high gloss with diamond lapping compound, rendering them almost featureless by secondary electron scanning electron microscopy. They were then examined at 10 to 30 kV in a Philips 505 instrument fitted with a 4-quadrant BE detector. Study of surfaces prepared approximately parallel to the natural surface showed that mineral was lost from both prism core and the interprismatic region, leaving a thin mineral-rich rim at the prism periphery. The same lesions viewed longitudinally on a surface prepared perpendicular to the natural surface showed mineral-rich bands at the prism margins in the outer enamel. Near the advancing front of the lesion, the prism junctions were widened and the prism cores sometimes hypermineralized. Natural lesions sectioned in the prism long axis showed features previously seen with other techniques, e.g., cross-striations and striae of Retzius, but in much greater detail. Mineral enrichment at the prism periphery in the lesion body and a widening of the prism junction at the advancing fronts of lesions in permanent teeth were most obvious. Calculations showed that with an accelerating voltage of 30 kV, the images reflected mineral density up to 4 µm beneath the surface. BE microscopy produces a high-resolution image of mineral loss or gain in carious enamel, with relatively easy sample preparation.

REFERENCES

• Arends, J.; Jongebloed, W.; Øgaard, B.; and Rølla, G. (1987): SEM and Microradiographic Investigation of Initial Enamel Caries, Scand J Dent Res 95:193-201.[Medline] [Order article via Infotrieve]
• Bergman, G. and Lind, P.O. (1966): A Quantitative Microradiographic Study of Incipient Enamel Caries, J Dent Res 45:1477-1484.[Free Full Text]
• Boyde, A. and Jones, S.J. (1983): Backscattered Electron Imaging of Dental Tissues, Anat Embryol 168:211-226.[Medline] [Order article via Infotrieve]
• Boyde, A.; Switsur, V.R.; and Stewart, A.D.G. (1963): An Assessment of Two New Physical Methods Applied to the Study of Dental Tissues. In: Advances in Fluorine Research and Dental Caries Prevention, J.L. Hard-wick, J.P. Dustin, and H.R. Held, Eds., Oxford: Pergamon Press, pp. 185-193.
• Buskes, J.A.K.M.; De Josselin DE Jong, E.; Christoffersen, J.; and Arends, J. (1987): Microradiographic Study on the Demineralization of Thick Enamel Sections. A Constant Composition Study, Caries Res 21:15-21.[Medline] [Order article via Infotrieve]
• Darling, A.I. (1956): Studies of the Early Lesion of Enamel Caries with Transmitted Light, Polarised Light and Radiography. Part II, Br Dent J 101:329-341.
• Darling, A.I. (1963): Microstructural Changes in Early Dental Caries. In: Mechanisms of Hard Tissue Destruction, R.F. Sognnaes, Ed., Washington, D.C.: American Association for the Advancement of Science, pp. 171-186.
• Fosdick, L.S. and Hutchinson, A.C.W. (1965): The Mechanism of Caries of Dental Enamel, Ann NY Acad Sci 131:758-770.[Medline] [Order article via Infotrieve]
• Frank, R.M.; Capitant, M.; and Goni, J. (1966): Electron Probe Studies of Human Enamel, J Dent Res 45:672-682.[Free Full Text]
• Gray, J.A. and Francis, M.D. (1963): Physical Chemistry of Enamel Dissolution. In: Mechanisms of Hard Tissue Destruction, R.F. Sognnaes, Ed., Washington, D.C.: American Association for the Advancement of Science, pp. 213-260.
• Haikel, Y.; Frank, R.M.; and Voegel, J.C. (1983): Scanning Electron Microscopy of the Human Enamel Surface Layer of Incipient Carious Lesions, Caries Res 17:1-13.[Medline] [Order article via Infotrieve]
• Holmen, L.; Thylstrup, A.; Øgaard, B.; and Kragh, F. (1985): A Scanning Electron Microscopic Study of Progressive Stages of Enamel Caries in vivo, Caries Res 19:355-367.[Medline] [Order article via Infotrieve]
• Hubbard, M.J. (1982): Correlated Light and Scanning Electron Microscopy of Artificial Carious Lesions, J Dent Res 61:14-19.[Abstract/Free Full Text]
• Ingram, G.S. and Fejerskov, O. (1986): A Scanning Electron Microscope Study of Artificial Caries Lesion Formation, Caries Res 20:32-39.[Medline] [Order article via Infotrieve]
• Johnson, N.W. (1967): Some Aspects of the Ultrastructure of Early Human Enamel Caries Seen with the Electron Microscope, Arch Oral Biol 12:1505-1521.[CrossRef][Medline] [Order article via Infotrieve]
• Johnson, N.W.; Poole, D.F.G.; and Tyler, J.E. (1971): Factors Affecting the Differential Dissolution of Human Enamel in Acid and EDTA. A Scanning Electron Microscope Study, Arch Oral Biol 16:385-396.[CrossRef][Medline] [Order article via Infotrieve]
• Jones, S.J. and Boyde, A. (1987): Scanning Microscopic Observations on Dental Caries, Scan Microsc 1:1991-2002.
• Kerckaert, G.A. (1973): Electron Microscopy of Human Carious Dental Enamel, Arch Oral Biol 18:751-758.[Medline] [Order article via Infotrieve]
• Orams, H.J.; Phakey, P.P.; Rachinger, W.A.; and Zybert, J.J. (1980): Ultrastructural Changes in the Translucent and Dark Zones of Early Enamel Caries, J Oral Pathol 9:54-61.[Medline] [Order article via Infotrieve]
• Pearce, E.I.F. and Gallagher, I.H.C. (1979): The Behaviour of Sucrose and Xylitol in an Intra-oral Caries Test, NZ Dent J 75:8-14.
• Pearce, E.I.F. and Nelson, D.G.A. (1988): In vivo Comparison of Caries Inhibition by a Plaque Mineral Enriching Mouthrinse and a Fluoride Dentifrice, Caries Res 22:362-370.[Medline] [Order article via Infotrieve]
• Peck, S.D. and Briggs, G.A.D. (1986): A Scanning Acoustic Microscope Study of the Small Caries Lesion in Human Enamel, Caries Res 20:356-360.[Medline] [Order article via Infotrieve]
• Peck, S.D. and Briggs, G.A.D. (1987): The Caries Lesion under the Scanning Acoustic Microscope, Adv Dent Res 1:50-63.[Abstract/Free Full Text]
• Risnes, S. (1986): Enamel Apposition Rate and the Prism Periodicity in Human Teeth, Scand J Dent Res 94:394-404.[Medline] [Order article via Infotrieve]
• Scott, D.B.; Simmelink, J.W.; and Nygaard, V. (1974): Structural Aspects of Dental Caries, J Dent Res 53:165-178.[Free Full Text]
• Shellis, R.P. and Hallsworth, A.S. (1987): Use of SEM in Studying Enamel Caries, Scan Microsc 1:1109-1123.
• Silverstone, L.M. (1973): Structure of Carious Enamel, Including the Early Lesion. In: Dental Enamel. Development, Structure and Caries, A.H. Melcher and G.A. Zarb, Eds., Oral Sciences Review No. 3, Copenhagen: Munksgaard, pp. 100-160.
• Silverstone, L.M. (1977): Remineralization Phenomena, Caries Res 11 (Suppl, 1):59-84.[Medline] [Order article via Infotrieve]
• Simmelink, J.W. and Nygaard, V.K. (1982): Ultrastructure of Striations in Carious Human Enamel, Caries Res 16:179-188.[Medline] [Order article via Infotrieve]
• Thylstrup, A. and Fejerskov, O. (1981): Surface Features of Early Carious Enamel at Various Stages of Activity. In: Tooth Surface Interactions and Preventive Dentistry, G. Rolla, T. Sonju, and G. Embery, Eds., London: IRL Press Ltd., pp. 193-205.
• Tyler, J.E. (1976): A Scanning Electron Microscope Study of Factors Influencing Etch Patterns of Human Enamel, Arch Oral Biol 21:765-769.[Medline] [Order article via Infotrieve]
• Wilson, D.F. and Shroff, F.R. (1972): Scanning Electron Microscopy of Carious Enamel, NZ Dent J 68:213-218.

Journal of Dental Research, Vol. 68, No. 2, 113-118 (1989)
DOI: 10.1177/00220345890680020301


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This Article Abstract Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Citing Articles Citing Articles via Google Scholar Citing Articles via Scopus Google Scholar Articles by Pearce, E.I.F. Articles by Nelson, D.G.A. Search for Related Content PubMed PubMed Citation Articles by Pearce, E.I.F. Articles by Nelson, D.G.A. Social Bookmarking                         What's this?