Galvanic corrosion between various combinations of orthodontic brackets and archwires.

Introduction: The purpose of this study was to compare galvanic currents generated by different combinations of commonly used brackets and archwires.

Methods: As-received stainless steel, nickel-titanium, and beta-titanium wires were coupled to stainless steel and titanium brackets in an artificial saliva medium. The galvanic current and amount of charge transferred for each pair were monitored with a zero resistance ammeter for 10 hours.

Results: Two-way analysis of variance (ANOVA) showed a significant difference in charge and galvanic currents when factored for type of bracket (P <0.001), but no significant difference between them when factored by type of wire (P >0.05). Specifically, a brazed stainless steel bracket was significantly greater in charge transferred and 10-hour galvanic current than metal injection molded stainless steel and titanium brackets (P <0.001), which were not different from each other (P >0.05).

Conclusions: The method of bracket manufacturing might be of equal or more relevance to galvanic corrosion susceptibility than bracket composition.