title: In vitro evaluation of physical vapor deposition coated beta titanium orthodontic archwires.
abstract: OBJECTIVE
  To determine in vitro the frictional properties, surface morphology, and load deflection rate with looped designs of two newly developed titanium aluminum nitride (TiAlN) and tungsten carbide/carbon (WC/C) physical vapor deposition (PVD) coated beta titanium orthodontic archwires coated with PVD.
  
  
  METHODS
  Frictional properties with Tidy's protocol, surface evaluation before and after friction testing with the help of scanning electron microscopy (ESEM), and load deflection rate with different orthodontic loops on Instron universal testing machine were evaluated.
  
  
  RESULTS
  The results clearly indicate reduced frictional properties for WC/C coated archwires when compared with uncoated and TiAlN coated archwires. There were no significant surface alterations upon ESEM evaluation of friction tested archwires. Low load deflection rate was exhibited by both coated archwires, the difference in load deflection rate between the coated and uncoated archwires was statistically significant.
  
  
  CONCLUSIONS
  WC/C coated wires can be recommended for even sliding mechanics due to reduced frictional properties, better surface characteristics, and low load deflection rate compared with TiAlN coated and uncoated archwires.
authors.affiliation: Department of Orthodontics, Sri Sankara Dental College, Varkala, Trivandrum, Kerala, India. vikrishnan@yahoo.com
authors.forename: Vinod
authors.initials: V
authors.lastname: Krishnan
authors.forename: K K
authors.initials: KK
authors.lastname: Ravikumar
authors.forename: K
authors.initials: K
authors.lastname: Sukumaran
authors.forename: K Jyothindra
authors.initials: KJ
authors.lastname: Kumar
mesh_terms: D020099:Coated Materials, Biocompatible; D003722:Dental Alloys; D003799:Dental Stress Analysis; D017276:Friction; D006801:Humans; D008422:Materials Testing; D016382:Orthodontic Appliance Design; D009969:Orthodontic Wires; D013499:Surface Properties; D014025:Titanium
chemical_list: D020099:Coated Materials, Biocompatible; D003722:Dental Alloys; C023988:beta titanium; D014025:Titanium