Sunday, November 23, 2014
Type of wire
How does the thickness of a wire affect the way the teeth are getting moved? Why do the wires have to be changed?
Wires come in different sizes, different constructions and also different materials. All of these factors affect how the wire moves the teeth. The two basic materials are stainless steel and Nickel Titanium alloy. SS is very stiff and stable so it is good for controlling tooth movement, and loops and designs can be bent in the wires by the orthodontist. NITI wire is very flexible but cannot be bent by the orthodontist to make fine adjustments in the position of the teeth. Some wires are woven from smaller wires to make them more flexible. Some wires are round to allow the wire to fit more easily into the braces. Some wires are square or rectangular to allow the orthodontist to control tooth movement in all dimensions.
The wires need to be changed to change the forces applied to the teeth. Sometimes the brace can be repositioned on the tooth instead of changing the wire but usually it is the changing of the wire that moves the teeth.
Mark G Hans, DDS, MSD
Professor of Orthodontics
School of Dental Medicine
Case Western Reserve University