title: Corrosion resistance measurements of dental alloys, are they correlated?
abstract: OBJECTIVE
  The aim was to assess in vitro the resistance to corrosion of eight commercial dental alloys by two quantitative methods, electrochemical and immersion tests, then to statistically test the hypothesis of possible correlation between the polarization resistance (R(p)) and the elemental release.
  
  
  METHODS
  Two quantitative methods; electrochemical and immersion test, were used. From the first, after recording the OCP during 24h immersion in acidified artificial saliva (pH 2.3), R(p) was obtained using the linear polarization in anodic path and applying the Mansfeld's method. From the static immersion test, using the same test solution, the elemental release from was analysed and determined using the ICP-AES. Thereafter, the two measurements were used to plot the regression line and to determine the correlation coefficient. The significance of the correlation was tested using F-test at a confidence interval of 0.99.
  
  
  RESULTS
  : The resistance to corrosion results obtained from the two methods were ranked and compared; an inverse relation between them was evident. Then, the obtained coefficient of correlation (R(2)) was 0.886. With the F-test at 0.99 confidence interval, the hypothesis was accepted as the calculated F was about 44 against critical F=13.7.
  
  
  CONCLUSIONS
  The correlation between the two measurements, R(p) and mass loss, was proved statistically significant. This result may provide a new approach to predict the corrosion behaviour of dental alloys by firstly using the easier methods.
authors.affiliation: LEIBO, EA 637, Faculté d'Odontologie de Lyon, rue Gauillaume Paradin, 69008 Lyon, France. rrsir@yahoo.fr
authors.forename: Rafah R
authors.initials: RR
authors.lastname: Al-Hity
authors.forename: Heinrich F
authors.initials: HF
authors.lastname: Kappert
authors.forename: Stéphane
authors.initials: S
authors.lastname: Viennot
authors.forename: Francis
authors.initials: F
authors.lastname: Dalard
authors.forename: Brigitte
authors.initials: B
authors.lastname: Grosgogeat
mesh_terms: D003343:Corrosion; D003722:Dental Alloys / Q000737:chemistry*; D004563:Electrochemistry; D007101:Immersion; D008422:Materials Testing; D012044:Regression Analysis; D013329:Structure-Activity Relationship
chemical_list: D003722:Dental Alloys