title: Morphological, chemical and structural characterisation of deciduous enamel: SEM, EDS, XRD, FTIR and XPS analysis.
abstract: OBJECTIVE
  The purpose of this study was to characterise the enamel surface of sound deciduous teeth in terms of morphology, chemical composition, structure and crystalline phases.
  
  
  METHODS
  The enamel of 30 human deciduous teeth was examined by: Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Spectroscopy (EDS), X-ray Powder Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), and X-ray Photoelectron Spectroscopy (XPS). Chemical differences between incisors and canines were statistically evaluated using the Mann-Whitney U test (p ≤ 0.05).
  
  
  RESULTS
  Three enamel patterns were observed by SEM: 'mostly smooth with some groves', 'abundant microporosities' and 'exposed prisms'. The average Ca/P molar ratios were 1.37 and 1.03 by EDS and XPS, respectively. The crystallite size determined by XRD was 210.82 ± 16.78 Å. The mean ratio between Ca bonded to phosphate and Ca bonded to hydroxyl was approximately 10:1.
  
  
  CONCLUSIONS
  The enamel of sound deciduous teeth showed two main patterns: 'mostly smooth with some groves' and 'abundant microporosities'. 'Exposed prisms' was a secondary pattern. There were slight variations among the Ca/P molar ratios found by EDS and XPS, suggesting differences in the mineral content from the enamel surface to the interior. The crystalline phases found in enamel were hydroxyapatite and carbonate apatite, with major type B than type A carbonate incorporation.
authors.affiliation: Center for Research and Advanced Studies in Dentistry (CIEAO), Faculty of Dentistry, Autonomous University of the State of Mexico, Toluca, Mexico.
authors.forename: C M
authors.initials: CM
authors.lastname: Zamudio-Ortega
authors.affiliation: Center for Research and Advanced Studies in Dentistry (CIEAO), Faculty of Dentistry, Autonomous University of the State of Mexico, Toluca, Mexico.
authors.forename: R
authors.initials: R
authors.lastname: Contreras-Bulnes
authors.affiliation: Center for Research and Advanced Studies in Dentistry (CIEAO), Faculty of Dentistry, Autonomous University of the State of Mexico, Toluca, Mexico.
authors.forename: R J
authors.initials: RJ
authors.lastname: Scougall-Vilchis
authors.affiliation: Center for Research in Sustainable Chemistry UAEM-UNAM (CCIQS). Faculty of Chemistry, Autonomous University of the State of Mexico, Toluca, Mexico.
authors.forename: R A
authors.initials: RA
authors.lastname: Morales-Luckie
authors.affiliation: Center for Research in Sustainable Chemistry UAEM-UNAM (CCIQS). Faculty of Chemistry, Autonomous University of the State of Mexico, Toluca, Mexico.
authors.forename: O F
authors.initials: OF
authors.lastname: Olea-Mejía
authors.affiliation: Center for Research and Advanced Studies in Dentistry (CIEAO), Faculty of Dentistry, Autonomous University of the State of Mexico, Toluca, Mexico.
authors.forename: L E
authors.initials: LE
authors.lastname: Rodríguez-Vilchis
mesh_terms: D001031:Apatites / Q000032:analysis; D002118:Calcium / Q000032:analysis; D003461:Crystallography; D003481:Cuspid / Q000737:chemistry / Q000648:ultrastructure; D003743:Dental Enamel / Q000737:chemistry / Q000648:ultrastructure*; D017886:Durapatite / Q000032:analysis; D006801:Humans; D006878:Hydroxides / Q000032:analysis; D007180:Incisor / Q000737:chemistry / Q000648:ultrastructure; D008855:Microscopy, Electron, Scanning; D010710:Phosphates / Q000032:analysis; D010758:Phosphorus / Q000032:analysis; D056951:Photoelectron Spectroscopy; D016062:Porosity; D013052:Spectrometry, X-Ray Emission; D017550:Spectroscopy, Fourier Transform Infrared; D014094:Tooth, Deciduous / Q000737:chemistry / Q000648:ultrastructure*; D014961:X-Ray Diffraction
chemical_list: D001031:Apatites; D006878:Hydroxides; D010710:Phosphates; D010758:Phosphorus; C030782:carboapatite; C031356:hydroxide ion; D017886:Durapatite; D002118:Calcium