Analysis of Dental Hard Tissue by Computerized Microdensitometry

Abstract

One method of quantitating mineral content in thin sections of dental hard tissue is microdensitometry of contact radiographs. This method is often applied to analysis of artificial caries lesions. Because there is great inter- and intra-tooth variability, a single microdensitometric scan will not accurately reflect the content or distribution of mineral within an individual lesion, or within a group of lesions. To increase the number of replicates that can be handled routinely, a computer-driven microdensitometer has been used with a step series of aluminum and enamel to quantitate mineral content values at approximately 1-μm intervals. Accurate assessment of an individual lesion was made possible by averaging multiple scans of the lesion on each of several thin sections prepared from the lesion. Mean mineral profiles of treatment groups were then made from the profiles of the individual lesion. These data reduction techniques allowed for a large number of replicates to be used in the measurement of remineralization. The computerized microdensitometric system described here was developed to allow for an objective, quantitative analysis of the mineral content of dental hard tissue.

Get full access to this article

View all access options for this article.

References

Angmar, B. ; Carlstrom, D. ; and Glas, J.E. (1963): Studies on the Ultrastructure of Dental Enamel. IV. The Mineralization of Normal Human Enamel, J Ultrastruct Res 8:12-23.

Bodecker, C.F. and Applebaum, E. (1931): Metabolism of the Dentine; Its Relation to Dental Caries and to the Treatment of Sensitive Teeth, Dent Cosmos 73:995-1010.

Crabb, H.S. and Mortimer, K.V. (1967): Two-Dimensional Microdensitometry, A Preliminary Report, Br Dent J 122 :337-343.

Elliott, J.C. ; Dowker, S.E.P. ; and Knight, R.D. (1981): Scanning X-ray Microradiography of a Section of a Carious Lesion in Dental Enamel, J Microsc 123:89-92.

Featherstone, J.D.B. ; Ten Cate, J.M. ; Shariati, M. ; and Arends, J. (1983): Comparison of Artificial Caries-like Lesions by Quantitative Microradiography and Microhardness Profiles, Caries Res 17:385-391.

Groeneveld, A. and Arends, J. (1975): Influence of pH and Demineralization Time on Mineral Content, Thickness of Surface Layer and Depth of Artificial Caries Lesions , Caries Res 9:36-44.

Groeneveld, A. ; Jongebloed, W. ; and Arends, J. (1974): The Mineral Content of Decalcified Surface Enamel. A Combined Microprobe-Quantitative Microradiography Study, Caries Res 8:267-274.

Groeneveld, A. ; Purdell-Lewis, D.J. ; and Arends, J. (1975): Influence of the Mineral Contet of Enamel on Caries-Like Lesions Produced in Hydroxyethyl Cellulose Buffer Solutions, Caries Res 9:127-138.

Hodge, H.C. ; Van Huysen, G. ; and Warren, S.L. (1938): Factors Influencing the Quantitative Measurement of the Roentgen-Ray Adsorption of Tooth Slabs. IX. Tube-Machine Combination Factors, Am J Roentgenol 40:108-125.

10.

Jarvis, L.R. (1981): Microdensitometry with Image Analyzer Video Scanners , J Microsc 121:337-346.

11.

Mellberg, J.R. and Chomicki, W.G. (1984): Calcium Effects on Fluoride Uptake from Monofluorophosphate in vivo, IADR Abst 63:No. 764.

12.

Mellberg, J.R. ; Chomicki, W.G. ; Mallon, D.E. ; and Cas-Trovince, L.A. ; Remineralization in vivo of Artificial Caries Lesions by a Monofluorophosphate Dentifrice, Caries Res, In press.

13.

Mellberg, J.R. and Mallon, D.E. (1984): Acceleration of Remineralization in vitro by Sodium Monofluorophosphate and Sodium Fluoride, J Dent Res 63:1130-1135.

14.

Mellberg, J.R. ; Nicholson, C.R. ; Franchi, G.J. ; En-Glander, H.R. ; and Mosley, G.W. (1977): Enamel Fluoride Uptake and Retention from Intensive APF Gel Applications in vivo, J Dent Res 56:716-721.

15.

Ten Cate, J.M. and Arends, J. (1980); Remineralization of Artificial Enamel Lesions in vitro. III. A Study of the Deposition Mechanism, Caries Res 14:351-358.

16.

Thewlis, J. (1940): The Structure of Teeth as Shown by X-ray Examination, Medical Research Council, London: Spec. Rep., Ser. No. 238.