CORROSION PROPERTIES OF TRADITIONAL VS. CAD/CAM FABRICATED ORTHODONTIC RETENTION WIRES
Date of Award
Summer 5-6-2026
Document Type
Thesis - Restricted
Degree Name
Master of Science (MS)
Department
Dentistry
First Advisor
David Berzins
Second Advisor
David Berzins
Third Advisor
Dawei Liu
Fourth Advisor
Spencer Pope
Abstract
Objective: The purpose of this study was to compare the corrosion properties of traditionally used orthodontic retention wires to those of a CAD/CAM fabricated nickel-titanium retention wire, Memotain. Given both the longstanding use of fixed retention and concerns regarding metal ion release and biocompatibility, this study aimed to investigate differences in the electrochemical properties and behaviors of various orthodontic retention wires. Methods: Five different orthodontic retention wires including round stainless steel, braided stainless steel, nickel-titanium (NiTi), titanium deadsoft, and Memotain (a CAD/CAM fabricated NiTi wire) were tested in Fusayama-Meyer artificial saliva solution using a potentiostat and three electrode electrochemical circuit (n=10/group). Three tests were performed, including measuring the open circuit potential (OCP) over three hours, polarization resistance (Rp), and cyclic polarization to determine the corrosion current (Icorr) and evidence of pitting corrosion on the wires. Data were analyzed using ANOVA and post-hoc Tukey tests (p < 0.05). Results: There were significant differences found among all the wire types for OCP, polarization resistance, and corrosion current. The Memotain, titanium deadsoft, and round stainless steel wires showed significantly higher values for OCP than the NiTi and braided stainless steel wires. The Memotain wire demonstrated the highest polarization resistance of all five tested wires. The Memotain, NiTi, and titanium deadsoft wires showed the lowest corrosion currents, while the braided stainless steel showed the highest corrosion current and was the only wire to consistently exhibit pitting corrosion. Conclusion: The CAD/CAM fabricated Memotain retainer exhibited favorable electrochemical behavior with high resistance to corrosion compared to other traditionally used orthodontic retention wires. The braided stainless steel wire showed the least favorable corrosion properties compared to the other wires. The results of this study suggest that the Memotain CAD/CAM fabricated retention wire is a clinically acceptable option for fixed orthodontic retention and does not pose increased corrosion risks compared to other traditional orthodontic retention wires. Further research is recommended to identify specific ions and their quantities released during corrosion.