Effects of electrobrightening on the fit surface of cobalt-chromium RPD frameworks.
OBJECTIVE
The purpose of this study was to compare 3 different electrobrightening techniques and 3 electrolytic solutions in their effects upon the fit surface of cast cobalt-chromium frameworks.


METHODS
Fifty cast cobalt-chromium frameworks, which were subsequently divided into batches of 10, were prepared according to a standard protocol. Three electrobrightening techniques were tested initially using a single brand of electrolyte (Croform) and a batch of 10 frameworks per technique. The loss of metal by weight was determined from the fit surface of each casting. The least corrosive technique of these 3 was used again with 2 other brands of electrolyte (Nobilium and E501) in a repetition of the protocol. The fit surfaces of 8 random samples cut from each batch of electrobrightened castings were viewed by scanning electron microscope (SEM).


RESULTS
Statistical analysis applying a one-way analysis of variance and Bonferroni's multiple comparison of means test demonstrated that one immersion of the framework for 10 minutes at 1 amp when used in conjunction with Nobilium electrolyte removed the least metal (P = 0.001). The SEM study suggested that the Nobilium electrolyte also produced the smoothest surface.


CONCLUSIONS
Electrobrightening techniques affect the amount of metal removed, and the electrolytic solution used influences the resultant surface.
Sinclair
G F
GF
Division of Prosthetic Dentistry, Floor 20, Guy's Tower, Guy's Hospital, London SE1 9RT, United Kingdom.
Radford
D R
DR
Sherriff
M
M
Walter
J D
JD
D000704:Analysis of Variance; D002858:Chromium Alloys / Q000737:chemistry*; D003343:Corrosion; D003722:Dental Alloys / Q000737:chemistry*; D003734:Dental Casting Investment / Q000737:chemistry*; D003779:Denture Design; D003832:Denture, Partial, Removable; D004572:Electrolysis / Q000379:methods*; D004573:Electrolytes / Q000737:chemistry; D006801:Humans; D007101:Immersion; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D012995:Solubility; D012996:Solutions / Q000737:chemistry; D013223:Statistics as Topic; D013499:Surface Properties
D002858:Chromium Alloys; D003722:Dental Alloys; D003734:Dental Casting Investment; D004573:Electrolytes; D012996:Solutions