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.

This study investigates the cytotoxicity of various orthodontic archwires, which are essential in directing tooth movement through biomechanical forces. With advancements in material science, different archwire materials have been developed to balance mechanical performance with aesthetic and biological considerations. The study focuses on evaluating the biocompatibility and mechanical properties of stainless steel, nickel–titanium, and chromium–cobalt archwires, particularly their cytotoxic effects on oral cavity cells. In vitro cell culture experiments with fibroblasts, combined with scanning electron microscopy (SEM) analysis, were conducted to assess cell viability and morphology. The results revealed significant differences in cytotoxicity, with copper wires showing high toxicity and causing extensive cell death, while nickel–titanium and chromium–cobalt wires supported better cell viability and healthier cell morphology. These findings highlight the importance of selecting archwire materials that ensure mechanical efficiency without compromising cellular health, emphasizing the need for ongoing assessment of material biocompatibility in the oral environment.