Evaluation of key parameters in a potentiostatic corrosion test for dental amalgam

• Published in: Dental materials 1999-11, Vol.15 (6), p.397-402
• Main Authors: Poduch-Kowalczyk, M.B., Marek, M., Lautenschlager, E.P.
• Format: Article
• Language: English
• Subjects: ADA standards; American Dental Association; Corrosion; Dental amalgam; Dental Amalgam - chemistry; Dental Amalgam - standards; Dentistry; Guidelines as Topic; Materials Testing - standards; Potentiostatic corrosion; Round robin study; United States
• ISSN: 0109-5641; 1879-0097
• DOI: 10.1016/S0109-5641(99)00063-9

Objectives: Participation in a Round Robin study of potentiostatic corrosion test guidelines for dental amalgam was undertaken for the purpose of developing an accurate set of draft guidelines. Methods: Dispersalloy, sybraloy, aristalloy, phasealloy, and tytin were used as the amalgam specimens. They were prepared following the guidelines, then coupled to a copper wire, cemented into glass tubes, and polished to a 600-grit finish. A corrosion cell was prepared using a carbon counter-electrode, a standard calomel electrode (SCE) as the reference electrode, and amalgam as the working electrode. A 37°C solution of 10 g/l NaCl with a minimum volume of 300 ml was used. Within 5 min of polishing, the open circuit potential (OCP) was recorded for 10 min. Next, the specimen was polarized to 0 mV versus SCE, and the currents were recorded for a 24-h time period. Corrosion results were analyzed statistically with one-way ANOVA ( psybraloy>(dispersalloy, phasealloy, tytin ) . Significance: Having run the initially proposed guidelines, a number of clarifying changes were made so that the corrosion susceptibilities of five dental amalgams could be clearly differentiated.