Niti Wires in Orthodontics

Titanium has been used as a structural metal ever since 1952 and its possible use in Orthodontics has been suggested periodically. Arch wire materials with a component of titanium became available to Orthodontics in the 1970's. Nitinol, a Stochiometric nickel titanium alloy was first introduced for use in orthodontics in 1971, and is available as NiTi, Nitinol, Orthonol, Sentinol and Titanol. Since their introduction, they became an integral part of orthodontic mechanotherapy due to their unique characteristics of low stiffness, super elasticity and high reversibility. They have substituted twisted steel wires for leveling because of its high resilience. The high spring back of Nitinol is useful in circumstances that require large deflections but low forces. This result in increased clinical efficiency of Nitinol and fewer archwire changes or activations are required in routine orthodontic mechanics.