Nickel titanium alloys in orthodontics. News, varieties, use

Abstract

BACKGROUND. Nickel-titanium alloys are "smart" intermetallic materials, defined by 2 notions: • with shape memory effect (SMA) • superelastic (SE). AIM. To evaluate the medico-technical qualities, varieties and use in orthodontics. MATERIAL AND METHODS. The study of the literature with reference to orthodontic biomaterials and the catalogues of the manufacturing companies revealed that Ni-Ti alloys are of choice in making superelastic and SMA orthodontic wires, springs, clips of some self-ligating brackets. RESULTS. The Ni-Ti wires were classified according to: • the effect produced similar to rubber, shape memory, superelastic; • the force produced austenite, martensite, stabilized. Superelastics: Rematitan; DuoForce CuNiTi, Titanol Triple Force; Nanda Braided CuNiTi; NT3 SE NiTi; Nitinol SE; TruFlex NiTi; CuNiTi 27°C, etc. Thermo-active, SMA-effect: Tensic, Equire - thermo-active; BioStarter; Therma-Ti, TriTanium Memory Wire; Neo-Sentalloy; Tru-FlexThermal Ni; CuNiTi 40°C. CONCLUSIONS. The Ni-Ti alloys are found in orthodontic treatment in the form of wires used for the alignment and leveling of dental arches, springs for closing/opening interdental spaces, easily maneuverable clips in self-ligating brackets. The shape memory effect allows the deformed wires to return by heating - martensitic transformation (equal to that of the body).