NiTi Thermal Orthodontic Archwire

TiNol-2 thermal archwires have martensite present at room temperature, but go through a transformation change to austenite, which strengthens the wire once placed in the mouth. TiNol-2 is soft outside the mouth for easier ligation, but elastic modulus increases to produce a fully austenitic wire once in the mouth. TiNol-2 archwires are the wire of choice for severe malocclusions, and offer earlier rectangular wire engagement. TiNol-2 is a very gentle wire and very comfortable for the patient. A .016X.022 rectangular archwire has approximately the same force as a .016 round TiNol-2 wire. Softness of wire makes it more vulnerable to permanent deformation compared to super elastic NiTi wires. But if the TiNol-2 is not deformed beyond the yield point while ligating, permanent deformation is avoidable.