Understanding the Effects of Sterilisation Methods on Orthodontic Archwires Properties: A Review

Sterilisation is the removal of all microorganisms, vegetative or spore-forming, from an article, surface or medium that can be accomplished through steam autoclaving, dry heat and cold solution following strict guidelines for efficient archwire sterilisation. Orthodontic archwire sterilisation is a concern because patients are often exposed to contaminated dental products. Thus, new and used arch wires will not show significant differences in terms of properties while in usage. This article presents a review of the sterilisation methods effects on the characteristics and properties of several types of orthodontic archwires including stainless steel (SS), nickel-titanium (NiTi), copper NiTi, beta titanium (β-Ti), heat-activated NiTi and titanium molybdenum (TiMb). Available records in “all databases” of Web of Science, PubMed, ScienceDirect, Scopus and Elsevier were searched, and other studies were manually searched using keywords, retrieved and compiled. Studies related to sterilisation of orthodontic archwires such as archwire type, sterilisation method, characterisation techniques and mechanical properties were summarised based on articles published from 1st July 2015 to 29th February 2024, and it is shown that the characteristics of orthodontic archwires may be affected by sterilisation techniques. Heat sterilisation can change the load-deflection properties of some wires, while the chemical composition and surface structures of archwires are unchanged. After sterilisation, the number of nickel ions released from the archwires does not increase significantly. The findings support the idea that archwire sterilisation procedures are an effective infection control treatment and facilitate the mechanical characterisation of orthodontic archwires.