title: Altered inorganic composition of dental enamel and dentin in primary teeth from girls with Turner syndrome.
abstract: In Turner syndrome (TS) one X-chromosome is missing or defective. The amelogenin gene, located on the X-chromosome, plays a key role during the formation of dental enamel. The aim of this study was to find support for the hypothesis that impaired expression of the X-chromosome influences mineral incorporation during amelogenesis and, indirectly, during dentinogenesis. Primary tooth enamel and dentin from girls with TS were analysed and compared with the enamel and dentin of primary teeth from healthy girls. Qualitative and quantitative changes in the composition of TS enamel were found, in addition to morphological differences. Higher frequencies of subsurface lesions and rod-free zones were seen in TS enamel using polarized light microscopy. Similarly, scanning electron microscopy showed that the enamel rods from TS teeth were of atypical sizes and directions. Using X-ray microanalysis, high levels of calcium and phosphorus, and low levels of carbon, were found in both TS enamel and dentin. Using microradiography, a lower degree of mineralization was found in TS enamel. Rule induction analysis was performed to identify characteristic element patterns for TS. Low values of carbon were the most critical attributes for the outcome TS. The conclusion was that impaired expression of the X-chromosome has an impact on dental hard tissue formation.
authors.affiliation: Department of Orthodontics, Institute of Odontology, Sahlgrenska Academy at the University of Gothenburg, Göteborg, Sweden.
authors.forename: Sara
authors.initials: S
authors.lastname: Rizell
authors.forename: Heidrun
authors.initials: H
authors.lastname: Kjellberg
authors.forename: Wolfram
authors.initials: W
authors.lastname: Dietz
authors.forename: Jörgen G
authors.initials: JG
authors.lastname: Norén
authors.forename: Ted
authors.initials: T
authors.lastname: Lundgren
mesh_terms: D000566:Amelogenesis / Q000235:genetics; D002118:Calcium / Q000032:analysis; D002244:Carbon / Q000032:analysis; D041321:Chromosomes, Human, X / Q000235:genetics; D003743:Dental Enamel / Q000737:chemistry* / Q000648:ultrastructure; D003804:Dentin / Q000737:chemistry* / Q000648:ultrastructure; D003810:Dentinogenesis / Q000235:genetics; D004577:Electron Probe Microanalysis; D005260:Female; D040181:Genetic Diseases, X-Linked / Q000235:genetics; D006801:Humans; D007621:Karyotyping; D051188:Knowledge Bases; D008852:Microradiography; D008855:Microscopy, Electron, Scanning; D008859:Microscopy, Polarization; D008903:Minerals / Q000032:analysis; D010100:Oxygen / Q000032:analysis; D010758:Phosphorus / Q000032:analysis; D014074:Tooth Calcification / Q000235:genetics; D014094:Tooth, Deciduous / Q000737:chemistry* / Q000648:ultrastructure; D014424:Turner Syndrome / Q000235:genetics / Q000378:metabolism* / Q000473:pathology
chemical_list: D008903:Minerals; D010758:Phosphorus; D002244:Carbon; D010100:Oxygen; D002118:Calcium