title: Wavelength-independent microradiography: a method for non-destructive quantification of enamel and dentin mineral concentrations using polychromatic x-rays.
abstract: Wavelength-independent Microradiography (WIM), described in this paper, used polychromatic, high-energy (less than or equal to 60 kV) x-rays for determination of mineral concentrations in tooth material non-destructively. This was done with the aid of a reference step-wedge made of 94% aluminum, 6% zinc. The mass attenuation coefficient of this material has a wavelength-independent ratio to the mass attenuation coefficients of enamel and dentin. With this method, mineral concentrations of enamel and dentin samples, with a thickness up to 500 microns, were determined at 20- and at 60-kV tube voltage. The samples were demineralized for 72 and 144 h and measured again. Comparison of the data showed that mineral quantification was within 1.5%, independent of the x-rays used. Finally, these mineral concentrations--obtained from the Wavelength-independent Microradiography--were compared with measurements of the same samples by Longitudinal Microradiography. A correlation of 0.99 was found for enamel and one of 0.96 for dentin.
authors.affiliation: Materia Technica, State University Groningen, The Netherlands.
authors.forename: F M
authors.initials: FM
authors.lastname: Herkströter
authors.forename: J J
authors.initials: JJ
authors.lastname: Ten Bosch
mesh_terms: D003743:Dental Enamel / Q000032:analysis*; D003804:Dentin / Q000032:analysis*; D008852:Microradiography / Q000379:methods*; D008903:Minerals / Q000032:analysis*
chemical_list: D008903:Minerals