title: [The effect of fluoride on dental alloys in different concentrations of fluoride artificial saliva].
abstract: OBJECTIVE
  To study the changes in surface morphology of cobalt-chromium alloy, pure titanium and high-cobalt chromium molybdenum alloy immersed in artificial saliva with different concentrations of fluoride, and to analyze the corrosion resistance of these metals.
  
  
  METHODS
  The three kinds of metal were polished and then were immersed in artificial saliva with different concentrations of fluoride (0%, 0.05%, 0.2%). All specimens were immersed for 3 weeks at (37.0 +/- 1.0) degrees C. Metal surface roughness before and after immersion were measured and analyzed by scanning electron microscope (SEM).
  
  
  RESULTS
  Metal surface roughness was increased with the concentration of fluoride. The surface roughness of the Co-Cr group and Ti group had a statistically significant difference between before and after immersion at the fluoride concentration of 0.05% (P<0.01), and the difference between Co-Cr group and vitallium2000 group, Ti group and vitallium2000 group were statistically significant difference (P<0.01). The differences of three groups before and after immersion were statistically significant at the fluoride concentration of 0.2% (P<0.01), and the difference among three groups was statistically significant (P<0.01).
  
  
  CONCLUSIONS
  Patients who frequently use fluoride products should not use pure titanium or cobalt-chromium alloy prosthesis. Patients with these three metal prostheses are not advised to use high concentration fluoride products.
authors.affiliation: Dept. of Prosthodontics, College of Stomatology, Shandong University, Jinan 250012, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Cheng
authors.forename: Haili
authors.initials: H
authors.lastname: Yu
authors.forename: Xuefen
authors.initials: X
authors.lastname: Lin
authors.forename: Xiaopeng
authors.initials: X
authors.lastname: Han
authors.forename: Liping
authors.initials: L
authors.lastname: Liu
authors.forename: Tingting
authors.initials: T
authors.lastname: Ding
authors.forename: Ping
authors.initials: P
authors.lastname: Ji
mesh_terms: D002858:Chromium Alloys; D003343:Corrosion; D003722:Dental Alloys; D005459:Fluorides; D006801:Humans; D008422:Materials Testing; D010710:Phosphates; D012464:Saliva, Artificial; D013499:Surface Properties; D014025:Titanium
chemical_list: D002858:Chromium Alloys; D003722:Dental Alloys; D010710:Phosphates; D012464:Saliva, Artificial; C012980:fluorophosphate; D014025:Titanium; D005459:Fluorides