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Detection of dental decay and its extent using a.c. impedence spectroscopy

Nature Medicine volume 2, pages 235237 (1996) | Download Citation



Dental caries (decay), the most prevalent of diseases, represents a health problem of immense proportions1. It principally affects posterior (back) teeth on occlusal (biting) and approximal (adjacent contacting) surfaces. Caries starts as a subsurface demineralization of enamel, may progress to the underlying dentine and, eventually, to cavitation of the surface. Accurate diagnosis before cavitation would permit targeted preventive treatment, thereby significantly improving dental health and reducing the need for expensive drilling and filling. Inaccessibility of caries initiation sites and recent changes in lesion morphology contribute to the relatively poor accuracy of conventional diagnostic methods2 Among alternative techniques, measurements of electrical resistance3–5 have shown the most promise. Here we describe a new experimental technique that demonstrates an outstanding 100% correlation between a.c. impedance measurements of whole teeth and the actual extent of approximal caries in vitro. Only relatively minor modifications should be required to transfer the technique to in vivo applications.

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  1. Department of Dental Health, University of Dundee Dental School,Park Place, Dundee, DD1 4HR, Scotland

    • Christopher Longbottom
    •  & Nigel B. Pitts
  2. TRIKON: Institute for Dental Clinical Research, Department of Cariology and Endodontology, University of Nijmegen, Nijmegen, The Netherlands

    • Marie-Charlotte D.N.J. Huysmans
  3. School of Chemistry, University of St. Andrews, St. Andrews, Scotland

    • Przemyslaw Los
    •  & Peter G. Bruce


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