Laboratory and clinical analyses of nitinol wire.

M an’s long history of technologic development has been marked by a continuing search for improved materials. This effort has resulted in vast arrays of new materials which have affected nearly every aspect of contemporary life, including orthodontics. A significant advance in orthodontic materials was made in the late 1930’s and 1940’s when stainless steel wire and appliances became widely available, Since that time there has been continuous evolutionary improvement in the strength and resilience of wires used for orthodontic treatment. The recent development of nitinol wire is another improvement which has emerged from the orthodontist’s search for lighter forces and greater working range. Nitinol was invented in the early 1960’s by William F. Buehler, a research metallurgist at the Naval Ordnance Laboratory in Silver Springs, Maryland (now called the Naval Surface Weapons Center). Mr. Buehler spent the next few years doing extensive research and publishing his findings on the properties and uses of his new alloy. The name nitinol is an acronym derived from the elements which comprise the alloy, ni for nickel and ti for titanium, and nof from Naval Ordnance Laboratory.