title: Etching effect of acidic fluorides on human tooth enamel in vitro.
abstract: OBJECTIVE
  This in vitro study aimed to examine the etching effect of acidic fluoride solutions on enamel.
  
  
  METHODS
  24 human teeth divided into 48 enamel-specimens were partly isolated with impression material. Specimens were exposed for 10 min to 20ml of the following solutions: 1.6% TiF4, 3.9% SnF2, 0.2% HF and 1.8% citric acid (CA). The isolation was removed and 24 specimens analysed by profilometry (Δheight: exposed/isolated enamel surfaces, surface roughness parameters). For the remaining 24 specimens [Ca(2+)] in the test solutions was analysed by atomic absorption spectroscopy.
  
  
  RESULTS
  Median Δheights (μm) after exposure were: TiF4 0.07, SnF2 -0.03, HF -0.14 and CA -5.92. TiF4-exposed surfaces showed both deposits and etched areas and exhibited statistically significant different surface roughness parameters compared to the HF- and SnF2-exposed surfaces. Median [Ca(2+)] values (ppm): TiF4 1.88, SnF2 0.11, HF 0.10 and CA 2.17.
  
  
  CONCLUSIONS
  At the [F] tested in this study it can be concluded that SnF2- and HF solutions had negligible erosive effects on enamel. TiF4 solution resulted in an incomplete surface deposition associated with calcium dissolution suggesting that TiF4 applied as solution may not be advisable.
authors.affiliation: Department of Prosthetic Dentistry and Oral Function, Faculty of Dentistry, University of Oslo, P.O. Box 1109, Blindern, 0317 Oslo, Norway. Electronic address: carl.hjortsjo@odont.uio.no.
authors.forename: Carl
authors.initials: C
authors.lastname: Hjortsjö
authors.affiliation: Oral Research Laboratory, Faculty of Dentistry, University of Oslo, P.O. Box 1109, Blindern, 0317 Oslo, Norway.
authors.forename: Grazyna
authors.initials: G
authors.lastname: Jonski
authors.affiliation: Department of Cariology and Gerodontology, Faculty of Dentistry, University of Oslo, P.O. Box 1109, Blindern, 0317 Oslo, Norway.
authors.forename: Alix
authors.initials: A
authors.lastname: Young
authors.affiliation: Department of Prosthetic Dentistry and Oral Function, Faculty of Dentistry, University of Oslo, P.O. Box 1109, Blindern, 0317 Oslo, Norway.
authors.forename: Erik
authors.initials: E
authors.lastname: Saxegaard
mesh_terms: D000134:Acid Etching, Dental; D019343:Citric Acid; D003743:Dental Enamel / Q000187:drug effects*; D005459:Fluorides; D006801:Humans; D006858:Hydrofluoric Acid; D066298:In Vitro Techniques; D013054:Spectrophotometry, Atomic; D013499:Surface Properties; D014002:Tin Fluorides; D014025:Titanium
chemical_list: D014002:Tin Fluorides; D019343:Citric Acid; D014025:Titanium; D005459:Fluorides; D006858:Hydrofluoric Acid; C032240:titanium tetrafluoride
keywords: Dental erosion; Fluorides; Hydrofluoric acid; Stannous fluoride; Titanium tetrafluoride