ISSN:
1432-0827
Keywords:
Fourier transform infrared spectroscopy
;
Photoacoustic spectroscopy
;
Depth profile
;
Enamel
;
Carbonate
;
Phosphate
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
,
Physics
Notes:
Abstract Photoacoustic Fourier transform infrared (PA-FT-IR) depth profiling spectra of the enamel of an intact human tooth are obtained in a completely nondestructive fashion. The compositional and structural changes in the tissue are probed from the enamel surface to a depth of about 200 μm. These changes reflect the state of tissue development. The subsurface carbonate gradient in the enamel could be observed over the range of about 10–100 μm. The carbonate-to-phosphate ratio increases in the depth profile. The depth profile also reveals changes in the substitutional distribution of carbonate ions. Type A carbonates (hydroxyl substituted) increase relative to type B carbonates (phosphate substituted) with increasing thermal diffusion length. In addition to the changes in the carbonate ion distribution and content, the PA-FT-IR depth profile clearly indicates a dramatic increase in the protein content relative to the phosphate content with increased depth. The changes in the carbonate content and distribution, along with the changes in the protein content, may be responsible for the changes observed in the apatitic structure in the depth profile of the enamel.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00334328
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