title: Studies on dental erosion: An in vivo-in vitro model of endogenous dental erosion--its application to testing protection by fluoride gel application.
abstract: BACKGROUND
  The objective in this study was to develop an in vivo-in vitro model of endogenous erosion, with a view to exploring the potential for some degree of its control by the use of topical fluoride gel application to teeth.
  
  
  METHODS
  Six volunteers each wore a small clasp retained palatal acrylic appliance to which six sterilized enamel tiles were bonded. Three tiles on each appliance were coated extra-orally with either 1.23 per cent acidulated phosphate fluoride (APF) or 2.2 per cent sodium fluoride (NaF) neutral gel for four minutes prior to multiple periods of exposure to the simulated gastric acid, cumulating in 16, 36, 80 and 150 minutes of exposure. Impressions of the enamel tiles prior to and following acid exposure permitted dies to be prepared. These were sectioned through the exposed areas and examined under a stereomicroscope to assess maximum depths of erosion.
  
  
  RESULTS
  The depth of erosive demineralization of enamel was found to be greatly reduced with increased frequency of APF gel application. The reduction in enamel loss was less following topical application of NaF gel.
  
  
  CONCLUSIONS
  It was concluded that fluoride gels significantly reduced enamel erosion using this in vivo-in vitro model and therefore, if prescribed appropriately, should help reduce tooth tissue loss from endogenous erosion.
authors.affiliation: Dental School, The University of Adelaide, South Australia.
authors.forename: L
authors.initials: L
authors.lastname: Jones
authors.forename: D
authors.initials: D
authors.lastname: Lekkas
authors.forename: D
authors.initials: D
authors.lastname: Hunt
authors.forename: J
authors.initials: J
authors.lastname: McIntyre
authors.forename: W
authors.initials: W
authors.lastname: Rafir
mesh_terms: D000149:Acidulated Phosphate Fluoride / Q000008:administration & dosage / Q000627:therapeutic use; D003743:Dental Enamel / Q000187:drug effects / Q000473:pathology; D005460:Fluorides, Topical / Q000008:administration & dosage / Q000627:therapeutic use*; D005782:Gels; D006801:Humans; D006851:Hydrochloric Acid / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D012969:Sodium Fluoride / Q000008:administration & dosage / Q000627:therapeutic use; D013997:Time Factors; D017001:Tooth Demineralization / Q000209:etiology / Q000473:pathology / Q000517:prevention & control; D014077:Tooth Erosion / Q000209:etiology* / Q000473:pathology / Q000517:prevention & control
chemical_list: D005460:Fluorides, Topical; D005782:Gels; D000149:Acidulated Phosphate Fluoride; D012969:Sodium Fluoride; D006851:Hydrochloric Acid