X-Ray attenuation measurements of a primary incisor tooth slice*

Primary teeth are easily accessible human tissues whose analysis can reveal child development. Elemental analysis can assess toxic exposures such as lead, and diagnose malnutrition and other conditions. Modern x-ray fluorescence (XRF) elemental analysis is nondestructive, fast, and inexpensive. XRF measurements of calcium (Ca) and strontium (Sr) concentrations require corrections for thickness, density, and elemental composition variations. Linear attenuation coefficient (μ) accounts for these variations. An incisor primary tooth was sonicated in distilled water for 2-3 hours, embedded in resin, and cut into thin slices with a diamond saw blade. Slice thickness, length, and width were 0.63 mm 5 mm, and 1-3 mm, respectively. A 3D positioning stage assembly placed the sample perpendicular to the microbeam from an integrated x-ray lens and x-ray tube unit. X-ray spectra were acquired by an x-ray detector in reflection and transmission geometries. Sequential 30-s transmission spectra at positions separated by 0.1 mm and 0.05 mm steps were acquired. Average μ values for photon energy range 9.6-15.5 keV, were in the 0.59 to 5.3 mm^-1, and 2.0 to 9.8 mm^-1 ranges for dentin and enamel, respectively. Ca and Sr concentrations from XRF and μ measurements will be determined in future work.