title: Forces in initial archwires during leveling and aligning: Anin-vitrostudy.
abstract: OBJECTIVE
  Thisin-vitrostudy 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.
  
  
  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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department of Orthodontics, R.I.M.S, Kadapa, Andhra Pradesh, India.
authors.forename: Rajesh Kumar
authors.initials: RK
authors.lastname: Reddy
authors.affiliation: Department of Public Health Dentistry, C.K.S Theja Institute of Dental Sciences, Tirupati, Andhra Pradesh, India.
authors.forename: Pavan K
authors.initials: PK
authors.lastname: Katari
authors.affiliation: Department of Orthodontics, R.I.M.S, Kadapa, Andhra Pradesh, India.
authors.forename: Tarun T
authors.initials: TT
authors.lastname: Bypureddy
authors.affiliation: Department of Periodontics and Implantology, Drs. SNR Siddhartha Institute of Dental Sciences, Chinnaoutpalli, Andhra Pradesh, India.
authors.forename: Venkata Naga Sri Harsha
authors.initials: VN
authors.lastname: Anumolu
authors.affiliation: Department of Orthodontics, KLRs Lenora Institute of Dental Sciences, Rajahmundry, Andhra Pradesh, India.
authors.forename: Yenugupalli
authors.initials: Y
authors.lastname: Kartheek
authors.affiliation: Department of Dentistry, GEMS Medical College, Srikakulam, Andhra Pradesh, India.
authors.forename: Nemala R V
authors.initials: NR
authors.lastname: Sairam
keywords: Activation force; deactivation force; leveling and aligning; stiffness