title: An in vitro model for the study of chemical exchange between glass ionomer restorations and partially demineralized dentin using a minimally invasive restorative technique.
abstract: OBJECTIVE
  This study was designed to validate an in vitro model of the Atraumatic Restorative Technique (ART). This model allowed in depth analyses of the migration of apatite forming Sr and F, from a glass-ionomer, Fuji IXGP (GC Corporation, Tokyo, Japan), into partly demineralized dentine. The second objective was to study the effects of the levels of mineral loss on such ionic exchange.
  
  
  METHODS
  Artificial lesions were created in thirty third molars, which were divided into three groups based on time of exposure to the demineralizing solution (7, 14 and 21 days). These were restored with Fuji IXGP and left for 21 days. The method of analysis was electron probe microanalysis (EPMA) with wavelength dispersive spectrometry (WDS). This combination can yield both qualitative identification of elements as well as quantitative compositional information, with a minimum detection limit of 0.01%.
  
  
  RESULTS
  The results indicated that there was no significant difference in the levels of Ca and P from the control and test sides for all three groups of demineralized dentine. The differences in the depth of penetration and the amount of Sr and F between control and test were significant.
  
  
  CONCLUSIONS
  The validity of the in vitro model was confirmed. There was migration of both strontium and fluorine to the artificially demineralized dentine in a pattern consistent with remineralization and similar to what was observed in a previous in vivo study.
authors.affiliation: Faculty of Health Sciences, School of Dentistry, University of Queensland, 200 Turbot St, Brisbane, QLD 4000, Australia. hienngodentistry@yahoo.com
authors.forename: Hien C
authors.initials: HC
authors.lastname: Ngo
authors.forename: Graham
authors.initials: G
authors.lastname: Mount
authors.forename: John
authors.initials: J
authors.lastname: McIntyre
authors.forename: Loc
authors.initials: L
authors.lastname: Do
mesh_terms: D001031:Apatites / Q000737:chemistry; D002118:Calcium / Q000032:analysis; D057087:Dental Atraumatic Restorative Treatment / Q000592:standards*; D003804:Dentin / Q000378:metabolism*; D004577:Electron Probe Microanalysis; D005459:Fluorides / Q000493:pharmacokinetics; D005899:Glass Ionomer Cements / Q000737:chemistry*; D006801:Humans; D010758:Phosphorus / Q000032:analysis; D013052:Spectrometry, X-Ray Emission; D013324:Strontium / Q000493:pharmacokinetics; D013696:Temperature; D013997:Time Factors; D017001:Tooth Demineralization / Q000378:metabolism* / Q000628:therapy; D014089:Tooth Remineralization / Q000379:methods
chemical_list: D001031:Apatites; D005899:Glass Ionomer Cements; C110713:fuji IX; D010758:Phosphorus; D005459:Fluorides; D002118:Calcium; D013324:Strontium