Metal Ion Release from Orthodontic Archwires: A Comparative Study of Biocompatibility and Corrosion Resistance

This study investigates the release of metal ions from commonly used orthodontic archwires, specifically, stainless steel (SS), nickel–titanium (NiTi), chromium–cobalt (CrCo), and titanium–molybdenum (TMA) alloys. To simulate oral conditions, each type of wire was immersed in artificial saliva at body temperature for a four-week period. Ion release levels were analyzed through ICP-OES mass spectrometry. The findings indicate that NiTi and CrCo wires released significantly higher amounts of nickel (Ni) and chromium (Cr) ions compared to SS wires. These findings underscore the potential risk of allergic reactions, particularly to nickel, and emphasize the need for careful consideration of biocompatibility in orthodontic material selection. This research also provides valuable insights aimed at minimizing adverse reactions in patients, especially those with metal allergies.