What material is commonly used to create an orthodontic arch wire?

The most common materials used to create orthodontic arch wires include stainless steel and nickel-titanium. Stainless steel is favored for its strength, rigidity, and resistance to deformation, which is essential for effectively moving teeth into the desired positions. Nickel-titanium, on the other hand, has unique properties that allow it to exhibit shape memory and superelasticity. This means that it can exert a constant force over time, which is particularly useful during various stages of orthodontic treatment.

Using both stainless steel and nickel-titanium allows orthodontists to take advantage of the strengths of each material. Stainless steel provides the necessary firmness for certain treatments, while nickel-titanium wires can help minimize discomfort for patients and maintain a light, continuous force on the teeth.

Plastic is generally not used for arch wires due to its lack of sufficient strength and stability. Gold alloy, while used in some dental applications, is less common for arch wires mainly due to cost and availability compared to the aforementioned materials. Thus, the option that combines the two most effective and widely used materials—stainless steel and nickel-titanium—is the best answer.