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Copper Ni-Ti arch wires comes with precise and consistent transformation temperatures. 270 C Super elastic Copper Ni-Ti 350 C Super elastic Copper Ni-Ti 400 C Super elastic Copper Ni-Ti 270 C Super Elastic Copper Ni-Ti (Round and Rectangular) This Ni-Ti wire generates forces in the high range of physiological force limits and produces constant unloading forces that can result in rapid tooth movement. Engagement force is lower than with other super elastic wires because of the lower loading forces built into copper alloy; at the same time, unloading force levels are comparable to traditional super elastic nickel titanium wires. 350 C Thermo-Active Copper Ni-Ti (Round, Rectangular and Square) 350 C Copper Ni-Ti generates mid-range constant force levels when the wire reaches mouth temperature. Early ligation is easier with full-size arch wires due to the lower loading forces. Unloading are forces are higher and more sustained than other shape memory wires when the wire reaches body temperature are desired,350C Copper Ni-Ti is the ideal wire. 400 C Thermo-Active Copper Ni-Ti (Rectangular) 400 C Copper Ni-Ti provides intermittent forces that are activated when the mouth temperature exceeds 400 C. It is useful as an initial wire and can be used to engage severely malaligned teeth (such as high cuspids) without creating damaging or painful levels of force or unwanted side effects. It is also the wire of choice for patients scheduled for long intervals between visits when control of tooth movement is a concern. Variants of NiTi Wires Super cable wires: These comprise of seven individual strands that are woven together in a long, gentle spiral to maximize flexibility and minimize force delivery. Turbo wire (Braided preformed nickel titanium)1 Turbo wire (Figure 5) combines the advantages of highly resilient NiTi with rectangular braided wire. The braiding process actually increases the super elastic properties of NiTi. This combination yields an efficient means to achieve torque control, with an initial wire, in even the most severe malocclusion. The wire is recommended as an initial wire to unravel and level while controlling torque and engaging brackets fully. It is also effective as a finishing wire, retaining torque but allowing vertical elastic use. Uses of NiTi • NiTi is the ideal arch wire for initial levelling and aligning. • NiTi is used for tooth separation. • In transverse expansion of maxilla, NiTi is used as palatal expander. • Titanal-XR is a NiTi which can be bent or contoured and which will not creep back.

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In BMA or “Bendable Marsel Alloy “cinched ends do not straighten out and accepts elastic hooks,tear drops, bayonets, and stops thus eliminating needs for auxiliaries. Turbo is the first braided NiTi wire is the choice when immediate torque control is essential during initial stages of levelling and aligning.

Alpha Titanium Consists of Titanium, Aluminium, and Vanadium. Because of its hexagonal lattice, it possesses fewer slip planes making it less ductile than Beta-Titanium. Alpha –Titanium gets hardened by absorbing intra oral free hydrogen ions which turn it into Titanium hydride, at oral temperature of 370C and 100% humidity. The wire becomes rather brittle to bend after a period of 6 weeks in the mouth. This phenomenon is due to Vanadium content. The wire is available as a combination, the anterior section is 0.018 x 0.025” rectangular for torque control and braking while the posterior section which is oval, tapering from 0.018” to 0.017 inch. Hence it can be used as a closing wire. Beta Titanium Wires (TMA) 26 Beta titanium wire was developed by Dr. Burstone CJ in 1980. It is commercially available as TMA (Titaniummolybdenum alloy). Beta titanium has a modulus of elasticity that is less than that of stainless steel and about twice that of Nitinol. This makes its use ideal in situations in which force less than those of stainless steel are necessary and in instances in which a lower modulus material such as Nitinol is inadequate to produce the desired force magnitudes. Furthermore, the relatively lower forces generated by beta-titanium wire imply that the counterproductive force vectors generated by beta. Titanium wires can be counteracted by smaller forces than those required for comparable stainless steel wires. Extaoral anchorage demands with best titanium wires will therefore be less than those for stainless steel wires. With half the force but twice the working range of stainless steel, TMA has indications for all stages of treatment. Because of its intermediate stiffness between stainless steel and Ni-Ti memory alloys, it is especially beneficial as a main working arch wire.TMA has good flexibility and spring back characteristics along with predictable forces for consistent control. In the initial stages, TMA is recommended for tooth alignment, space closure and curve of spee. In the intermediate stages, TMA is recommended for early torque control with moderate forces.TMA also provides complete modification of the wire for dimensional control. Indications include use as an ideal retraction arch while exerting more constant moderate forces over a longer period of time. In the final stage of the treatment, TMA is used as a detailing wire with moderate force. The springback for beta titanium is superior to that of stainless steel. A beta-titanium wire can therefore be deflected almost twice as much as a stainless steel wire without permanent deformation. This makes it an excellent choice for auxiliary springs and for intermediate and finishing archwires, especially rectangular wires for the late stages of edgewise treatment. Its properties are intermediate between SS and M-NiTi. When compared with Nitinol, TMA was inherently smoother, could IJO

VOL. 25

NO. 3

FALL 2014

International Journal of Orthodontics  
International Journal of Orthodontics  
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