Evaluation of torque moment in a novel elastic bendable orthodontic wire.

The objective of the study was to measure the torque moment delivered by a novel elastic bendable wire, Ti-Nb wire, and to compare it with nickel-titanium (Ni-Ti) and titanium-molybdenum (Ti-Mo) alloy wires. Two sizes of Ti-Nb, Ni-Ti and Ti-Mo alloy wires and 0.022-inch slot stainless steel brackets were ligated with elastic modules or ligature wires. The torque moment delivered by the various wire-bracket combinations was measured using a torque gauge at the temperature and humidity of 37°C and 50%, respectively. As the degree of applied torque and the inserted wire size increased, the torque moment gradually increased. The torque moment of Ti-Nb wires was smaller than those of Ni-Ti wires and Ti-Mo wires, at more than 20 degrees applied torque. The torque moment with wire ligation was significantly larger than those with elastic ligation.