An Overview of the Mechanical Properties of the Orthodontic Wires: A Review

Introduction: This review aimed to provide theoretical support, based on orthodontics and mechanical engineering concepts, toemphasize the applicability and the mechanical properties involved in stainless steel, cobalt chromium, titanium-molybdenum andtitanium based alloys for specialists in this field. Materials and Methods: The search strategy for articles selection was focused on PubMed and Scopus from 1963 to 2024. Results: A total of 501 citations were identified by Medline (through PubMed) and 478 by Scopus. A total of 68 articles wereconsidered eligible for describing the basic mechanical properties of alloys and thermal tests, and tests to examine the strength ofmaterials and the surface of the material or its crystallography. Conclusion: Metallic alloys contain specific characteristics, such as resilience, rigidity, stored energy, formability, low frictionsurface, low cost and biocompatibility. Stainless Steel (SS) wires have the advantage of low cost and good corrosion resistance,good resilience and good formability. Cobalt-chromium and nickel-chromium have characteristics very close to SS wires butare expensive. Titanium-molybdenum alloys revealed springback superior than SS wires, good formability and high frictioncoeffient. Nickel-titanium based wires present poor formability, high friction coeffient, even though some of them present theshape memory effect and superelasticity. Ti-Nb(niobium) and Timolium present intermediate properties in relation to SS andTMA wires. Aesthetic alloys are fragile to fracture and relaxation fatigue over time and are dependent on moisture absorptionand temperature changes. The properties of metallic wires are function of wire composition, variables during machining processand heat treatment.