title: [Microdiffraction measurements of natural tooth by high resolution X-ray diffraction equipment].
abstract: The main mineral component of natural tooth was determined as calcium apatite many years ago; most of them exist in the form of hydroxyapatite with different crystallites. If a tooth decayed, the crystalline of hydroxyapatite would be changed and decomposed. In our experiment, a natural tooth with caries was measured by high resolution XRD equipment: X'pert Pro. Three spots which included normal enamel, normal dentin and caries tissue were analyzed. The results showed that tooth was a kind of biological mixed crystal composed of many crystal phases, the main crystal phase was hydroxyapatite. From normal enamel to normal dentin and to caries tissue, the length of the a-axis of hydroxyapatite crystallite increased, the length of the c-axis of hydroxyapatite crystallite remained unchanged. The crystal sizes were: normal enamel D002 = 27.600 nm; normal dentin D002 = 16.561 nm; caries tissue D002 = 13.163 nm. Crystallinity: normal enamel>normal dentin>caries tissue. According to our experiment, tooth could be conveniently studied by high resolution microdiffracion XRD equipment.
authors.affiliation: Key Lab. of Oral Biomedical Engineering of Ministry of Education, Sichuan University, Chengdu 610041, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Xue
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.forename: Yunmao
authors.initials: Y
authors.lastname: Liao
authors.forename: Jinglin
authors.initials: J
authors.lastname: Zhou
authors.forename: Jukun
authors.initials: J
authors.lastname: Song
mesh_terms: D003731:Dental Caries / Q000378:metabolism; D003743:Dental Enamel / Q000737:chemistry; D003804:Dentin / Q000737:chemistry; D006801:Humans; D014070:Tooth / Q000737:chemistry*; D014961:X-Ray Diffraction / Q000379:methods*