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Force System with Vertical V-Bends: A 3D In Vitro Assessment of Elastic and Rigid Rectangular Archwires
Published on: July 24, 2018
Forces in initial archwires during leveling and aligning: An in-vitro study
Rajesh Kumar Reddy1, Pavan K Katari2, Tarun T Bypureddy1
1Department of Orthodontics, R.I.M.S, Kadapa, Andhra Pradesh, India.
Aim:
This in-vitro study measured the force deflection behavior of selected initial alignment archwires by conducting three-point bending tests under controlled tests. The study tested three wire designs, namely, co-axial multistranded stainless steel wires, nickel-titanium, and copper-nickel-titanium archwires.
Materials And Methods:
The archwires were ligated to a specially designed metal jig, simulating the arch. A testing machine (Instron) recorded activation and deactivation forces of different deflections at 37°C. Forces on activation and deactivation were compared by one-way analysis of variance (ANOVA).
Results:
Significant differences (P < 0.05) in activation and deactivation forces were observed among the tested wires. The co-axial multistranded wire had the lowest mean activation and deactivation forces, whereas conventional nickel-titanium wires had more mean activation and deactivation forces at different deflections.
Conclusion:
The activation and deactivation forces were higher for nickel-titanium followed by copper-nickel titanium and co-axial wires. The amount of percentage force loss was more for co-axial wire, indicating that these wires are not ideal for initial leveling and aligning.

