ABSTRACT
Shape memory alloys (SMAs) refer to a special type of alloy that can recover its initial shape after severe deformations. SMAs have two different phases: the high-temperature phase named austenite and the low-temperature one called martensite. Both have different crystal structures and therefore different properties. The superelasticity of SMAs relates to stress-induced transformation at a temperature above the austenitic finish temperature. Biocompatibility studies indicate that SMA NiTi alloys have low cytotoxity and genotoxicity , which allows for the possibility of their application in orthodontics. The orthodontic wire, as a part of a fixed orthodontic appliance, delivers a force on teeth that permits tooth movement without tissue damage. A vacuum-tight shape memory flange was designed for the JET in-vessel inspection system, composed of an SMA sleeve and the base connecting the flange to the other apparatus.
