Date of Award
Master of Science (MS)
Objective: It is known that stainless steel and other alloys readily corrode in the oral environment. Many different wire compositions and configurations are available on the market for fixed orthodontic retainers, yet few studies have focused on the corrosion of wires used for fixed retention. The aim of this study was to determine the general and crevice corrosion properties of 7 distinct fixed retainer wires. Methods: Seven types of fixed retainer wires were chosen for testing – solid, braided and twisted stainless steel wires; solid and twisted gold plated wires; a solid cobalt chromium wire; and a solid beta-titanium ribbon. Ten segments of each wire type were tested in both of two tests: an artificial saliva solution and a 6% iron chloride solution to determine the effects of general and crevice corrosion, respectively. Open circuit potential (OCP) at 3 hours, polarization resistance (Rp), and corrosion rate (Icorr) were measured with a potentiostat. Potentiodynamic curves were evaluated to determine if pitting corrosion was present. Statistical analysis was completed with analysis of variation (ANOVA) and Tukey tests.