title: Evaluating the Surface Characteristics of Stainless Steel, TMA, Timolium, and Titanium-niobium Wires: An in vivo Scanning Electron Microscope Study.
abstract: BACKGROUND
  Recent metallurgical research and advancement in material science has benefited orthodontists in the selection of an appropriate wire size and alloy type, which is necessary to provide an optimum and predictable treatment results. The purpose of the study was to clinically evaluate and compare the surface characteristics of 16 x 22 stainless steel, Titanium molybdenum alloy, timolium, and titanium-niobium before and after placing them in a patient's mouth for 3 months using a scanning electron microscope (SEM).
  
  
  METHODS
  The total sample size was 40, which were divided into four groups (group 1 - stainless steel wires, 10 samples, group 2 - TMA wires, 10 samples, group 3 - timolium wires, 10 samples, and group 4 - titanium-niobium wires, 10 samples), and these were further subdivided into 5 each. The first subgroup of five samples was placed in the patient's mouth and was evaluated under SEM, and another subgroup of five samples was directly subjected to the SEM.
  
  
  RESULTS
  Scanning electron microscopic evaluation of surface characteristics of unused 16 x 22 rectangular stainless steel wire under 500 x magnification showed an overall smooth surface. Stainless steel wire samples placed in the patient's mouth showed black hazy patches, which may be interoperated as areas of stress. TMA unused wires showed multiple small voids of areas and small craters with fewer elevated regions. The TMA wire samples placed in the patient's mouth showed black hazy patches and prominent ridges, making the wire rougher. Timolium unused archwires showed heavy roughness and voids, whereas wires tested in the patient's mouth showed homogeneous distribution of deep cracks and craters. Unused titanium-niobium archwires showed uniform prominent striations and ridges with occasional voids, whereas wires used in the patient's mouth showed prominent huge voids that could be interpreted as maximum stress areas.
  
  
  CONCLUSIONS
  Stainless steel (group 1) used and unused wires showed smooth surface characteristics when compared with all the other three groups followed by timolium, which was superior to titanium-niobium wires and TMA wires.
  
  
  CONCLUSIONS
  Timolium wires are superior to titanium-niobium wires and TMA wires.
authors.affiliation: Reader, Department of Orthodontics and Dentofacial Orthopedics Indira Gandhi Institute of Dental Sciences, Puducherry, India, Phone: +919908645099, e-mail: drpradeepkommi@gmail.com.
authors.forename: K Pradeep
authors.initials: KP
authors.lastname: Babu
authors.affiliation: Department of Orthodontics and Dentofacial Orthopedics Indira Gandhi Institute of Dental Sciences, Puducherry, India.
authors.forename: V Naga
authors.initials: VN
authors.lastname: Keerthi
authors.affiliation: Department of Orthodontics and Dentofacial Orthopedics, Mar Baselios Dental College, Ernakulam, Kerala, India.
authors.forename: Deepika
authors.initials: D
authors.lastname: Madathody
authors.affiliation: Department of Orthodontics and Dentofacial Orthopedics Paneeniya Institute of Dental Sciences, Hyderabad, Telangana India.
authors.forename: A Laxmi
authors.initials: AL
authors.lastname: Prasanna
authors.affiliation: Department of Prosthodontics, Saveetha Dental College Chennai, Tamil Nadu, India.
authors.forename: Vidhya
authors.initials: V
authors.lastname: Gopinath
authors.affiliation: Department of Orthodontics and Dentofacial Orthopedics Indira Gandhi Institute of Dental Sciences, Puducherry, India.
authors.forename: M Senthil
authors.initials: MS
authors.lastname: Kumar
authors.affiliation: Department of Orthodontics and Dentofacial Orthopedics Meenakshi Ammal Dental College, Chennai, Tamil Nadu, India.
authors.forename: A Nanda
authors.initials: AN
authors.lastname: Kumar
mesh_terms: D003722:Dental Alloys; D003799:Dental Stress Analysis; D004548:Elasticity; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D009556:Niobium; D016910:Orthodontic Brackets; D009969:Orthodontic Wires; D013193:Stainless Steel; D013314:Stress, Mechanical; D013499:Surface Properties; D014025:Titanium
chemical_list: D003722:Dental Alloys; D009556:Niobium; D013193:Stainless Steel; D014025:Titanium
keywords: Scanning electron microscope; Stainless steel wires; Surface characteristics; TMA wires.; Timolium wires; Titanium-niobium wires