<abstract xmlns="http://www.w3.org/1999/xhtml">

<p>Simulated fixed orthodontic appliances were constructed, immersed and incubated in artificial saliva for periods up to three months. Two types of stainless steel archwires and two types of NiTi wires were used. The surface corrosion of the archwires was determined macroscopically, with scanning electron microscopy, and with spectrophotometry. The deposits on the wires were identified with X-ray diffraction. Uniform corrosion was observed on stainless steel wires, and a slight colour change was detected on the NiTi wires beneath stainless steel ligatures. The corrosion product on the stainless steel wires increased with immersion time, and the surface oxide films were easily detached from the underlying matrix. Crevice corrosion was observed under deposits of oxide, and at the interface between bracket and band. Such corrosion may weaken a wire or weld leading to fracture. In contrast, the NiTi archwires did not corrode, and there was no significant difference in surface morphology. The stainless steel archwires showed a significant loss of reflectance after heat treatment and immersion in artificial saliva. The NiTi archwires had the same reflectance before and after the immersion test. NiTi archwires are significantly more stable and resistant to corrosion than stainless steel archwires.</p>
</abstract>

Simulated fixed orthodontic appliances were constructed, immersed and incubated in artificial saliva for periods up to three months. Two types of stainless steel archwires and two types of NiTi wires were used. The surface corrosion of the archwires was determined macroscopically, with scanning electron microscopy, and with spectrophotometry. The deposits on the wires were identified with X-ray diffraction. Uniform corrosion was observed on stainless steel wires, and a slight colour change was detected on the NiTi wires beneath stainless steel ligatures. The corrosion product on the stainless steel wires increased with immersion time, and the surface oxide films were easily detached from the underlying matrix. Crevice corrosion was observed under deposits of oxide, and at the interface between bracket and band. Such corrosion may weaken a wire or weld leading to fracture. In contrast, the NiTi archwires did not corrode, and there was no significant difference in surface morphology. The stainless steel archwires showed a significant loss of reflectance after heat treatment and immersion in artificial saliva. The NiTi archwires had the same reflectance before and after the immersion test. NiTi archwires are significantly more stable and resistant to corrosion than stainless steel archwires.

<italic>In vitro</italic> surface corrosion of stainless steel and NiTi orthodontic appliances

DDS, PhD Professor, Department of Orthodontics College of Dentistry

Australasian Orthodontic Journal

This work is licensed under the Creative Commons Attribution 4.0 International License.

 surface corrosion of stainless steel and NiTi orthodontic appliances

Simulated fixed orthodontic appliances were constructed, immersed and incubated in artificial saliva for periods up to three months. Two types of stainless...

In vitro surface corrosion of stainless steel and NiTi orthodontic appliances

Published Online: Dec 15, 2023

Page range: 13 - 18

Received: Jul 01, 2002

Accepted: Feb 01, 2003

DOI: https://doi.org/10.2478/aoj-2003-0002

© 2003 Ji-Soo Shin et al., published by Sciendo

This work is licensed under the Creative Commons Attribution 4.0 International License.