Nitinol stands for Nickel Titanium Naval Ordinance Laboratory, was invented by William R. Buchler and introduced in Orthodontics by Andersen in 1971. it exhibits the exquisite property of Superelasticity and Shape memory. It exists in two allotropic forms: Austenite and Martensite. Shape of the wire is set in Austenite phase. Owing to its superelastic property, the wire can be elastically deformed to a great extent without increasing much force. Copper Ni-Ti or Thermal A-NiTi wires were introduced by Rohit Sachdeva and Suichi Miyaski (1994). It is available in temp ranges of 15, 27, 35 and 40 C.
Beta titanium were introduced by Jon Goldberg and C. J. Burstone, and available under the trade name of T.M.A. wires.
Optiflex arch wires are clear optical fibre which were developed by M.F. Talass in 1992. They are composed of a Silicon dioxide core which provides the force or resilience to the wire.
Multistranded arch wires are made up of several thinner wires, either twisted or coaxial. They apply light continuous forces.
