title: The Effect of Porcelain Firing on Electrochemical Behavior of a Dental Alloy in Hydrogen Peroxide.
abstract: OBJECTIVE
  The aim of this study was to evaluate changes in electrochemical corrosion properties of porcelain firing simulated nickel-chromium dental casting alloy exposed to a 10% hydrogen peroxide bleaching agent.
  
  
  METHODS
  The electrochemical corrosion behavior of a Ni-Cr alloy was evaluated by cyclic polarization test in the aerated electrolyte (pH = 6.5). Test groups were produced in as-cast (group 1, control group) and simulated porcelain firing (group 2: heat-treated/mean value; group 3: heat-treated/cycle) conditions. Scanning electron microscopy (SEM) was also used to examine the alloy surfaces before and after the corrosion test.
  
  
  RESULTS
  The ranking of the groups with respect to Ecorr and Icorr was as follows: 1, 2, 3 and 3, 1, 2, respectively. Group 3 exhibited the greatest and group 2 displayed the least corrosion tendencies. An increase in corrosion rates was observed after heat treatment/cycle state. Post-corrosion SEM photographs were also consistent with the test results.
  
  
  CONCLUSIONS
  Within the parameters of this study, a single heat treatment is insufficient to cause upheaval in corrosion behavior of a Ni-Cr alloy subjected to 10% hydrogen peroxide.
authors.affiliation: Department of Prosthodontics, Faculty of Dentistry, Gazi University, Ankara, Turkey.
authors.forename: Evşen
authors.initials: E
authors.lastname: Tamam
authors.affiliation: Department of Prosthodontics, Faculty of Dentistry, Ankara University, Ankara, Turkey.
authors.forename: A Kevser
authors.initials: AK
authors.lastname: Aydın
authors.affiliation: Department of Physical Chemistry, Faculty of Dentistry, Ankara University, Ankara, Turkey.
authors.forename: Semra
authors.initials: S
authors.lastname: Bilgiç
mesh_terms: D002858:Chromium Alloys; D003343:Corrosion; D003722:Dental Alloys; D003776:Dental Porcelain; D006861:Hydrogen Peroxide; D013499:Surface Properties
chemical_list: D002858:Chromium Alloys; D003722:Dental Alloys; D003776:Dental Porcelain; D006861:Hydrogen Peroxide
keywords: Ni-Cr alloy; SEM; corrosion; hydrogen peroxide; porcelain firing