title: Linking microstructure and nanochemistry in human dental tissues.
abstract: Mineralized dental tissues and dental pulp were characterized using advanced analytical transmission electron microscopy (TEM) methods. Quantitative X-ray energy dispersive spectroscopy was employed to determine the Ca/P and Mg/P concentration ratios. Significantly lower Ca/P concentration ratios were measured in peritubular dentine compared to intertubular dentine, which is accompanied by higher and variable Mg/P concentration ratios. There is strong evidence that magnesium is partially substituting calcium in the hydroxyapatite structure. Electron energy-loss near-edge structures (ELNES) of C-K and O-K from enamel and dentine are noticeably different. We observe a strong influence of beam damage on mineralized dental tissues and dental pulp, causing changes of the composition and consequently also differences in the ELNES. In this article, the importance of TEM sample preparation and specimen damage through electron irradiation is demonstrated.
authors.affiliation: Stuttgart Center for Electron Microscopy, Max Planck Institute for Intelligent Systems, Heisenbergstrasse 3, 70569 Stuttgart, Germany. srot@is.mpg.de
authors.forename: Vesna
authors.initials: V
authors.lastname: Srot
authors.forename: Birgit
authors.initials: B
authors.lastname: Bussmann
authors.forename: Ute
authors.initials: U
authors.lastname: Salzberger
authors.forename: Christoph T
authors.initials: CT
authors.lastname: Koch
authors.forename: Peter A
authors.initials: PA
authors.lastname: van Aken
mesh_terms: D002130:Calcium Phosphates / Q000032:analysis; D017886:Durapatite / Q000032:analysis; D006801:Humans; D017616:Magnesium Compounds / Q000032:analysis; D046529:Microscopy, Electron, Transmission; D010710:Phosphates / Q000032:analysis; D013052:Spectrometry, X-Ray Emission; D014070:Tooth / Q000737:chemistry* / Q000648:ultrastructure*
chemical_list: D002130:Calcium Phosphates; D017616:Magnesium Compounds; D010710:Phosphates; C030781:magnesium phosphate; D017886:Durapatite; C020243:calcium phosphate