title: The crystallographic properties of the mineral phases of enamel and dentin in normal deciduous and permanent teeth.
abstract: OBJECTIVE
  To investigate the crystallographic properties of the mineral phases of normal enamel and dentin (dental apatite) in deciduous and permanent teeth.
  
  
  METHODS
  Three kinds of physical methods including X-ray diffraction (XRD), infrared absorption spectroscope (IR) and electron probe micro-analysis (EPMA) were utilized in this study.
  
  
  RESULTS
  Dental apatite was not uniphase, but multiphase, which could be described as carbonate-substituted hydroxyapatite. Compared to dentin apatite, the higher crystallinity and expanded a-axis lattice parameters were found in enamel. Chemical analyses demonstrated that higher concentrations of Mg and CO(3)(2-) were found in dentin than those of enamel. But enamel had higher Cl content.
  
  
  CONCLUSIONS
  The differences among enamel and dentin, in terms of lattice parameter and crystallinity may be partially attributed to the incorporation of Mg, CO(3)(2-) and Cl minor elements.
authors.affiliation: Department of Operative Dentistry and Endodontics, Guanghua Hospital of Stomotology, Sun Yat-Sen University, Guangzhou 510060, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhao
authors.forename: Shuozhi
authors.initials: S
authors.lastname: Wang
authors.forename: Hanlie
authors.initials: H
authors.lastname: Hong
authors.forename: Zhi
authors.initials: Z
authors.lastname: Chen
authors.forename: Mingwen
authors.initials: M
authors.lastname: Fan
authors.forename: Shifeng
authors.initials: S
authors.lastname: Yu
mesh_terms: D003743:Dental Enamel / Q000737:chemistry*; D003804:Dentin / Q000737:chemistry*; D004577:Electron Probe Microanalysis / Q000379:methods; D006801:Humans; D013055:Spectrophotometry, Infrared / Q000379:methods; D014070:Tooth / Q000737:chemistry*; D014961:X-Ray Diffraction / Q000379:methods*