title: Debris, roughness and friction of stainless steel archwires following clinical use.
abstract: OBJECTIVE
  To investigate the degree of debris, roughness, and friction of stainless steel orthodontic archwires before and after clinical use.
  
  
  METHODS
  For eight individuals, two sets of three brackets (n = 16) each were bonded from the first molar to the first premolar. A passive segment of 0.019- x 0.025-inch stainless steel archwire was inserted into the brackets and tied by elastomeric ligature. Debris level (via scanning electron microscopy), roughness, and frictional force were evaluated as-received and after 8 weeks of intraoral exposure. Mann-Whitney, Wilcoxon signed-rank, and Spearman correlation tests were used for statistical analysis at the .05 level of significance.
  
  
  RESULTS
  There were significant increases in the level of debris (P = .0004), roughness of orthodontic wires (P = .002), and friction (P = .0001) after intraoral exposure. Significant positive correlations (P < .05) were observed between these three variables.
  
  
  CONCLUSIONS
  Stainless steel rectangular wires, when exposed to the intraoral environment for 8 weeks, showed a significant increase in the degree of debris and surface roughness, causing an increase in friction between the wire and bracket during the mechanics of sliding.
authors.affiliation: Department of Orthodontics, Brazil Federal University, Pará State, Belém, Brazil.
authors.forename: Isabella Silva Vieira
authors.initials: IS
authors.lastname: Marques
authors.forename: Adriana M
authors.initials: AM
authors.lastname: Araújo
authors.forename: Júlio A
authors.initials: JA
authors.lastname: Gurgel
authors.forename: David
authors.initials: D
authors.lastname: Normando
mesh_terms: D000328:Adult; D003722:Dental Alloys / Q000737:chemistry*; D020724:Elastomers / Q000737:chemistry; D005260:Female; D017276:Friction; D006801:Humans; D008297:Male; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D016910:Orthodontic Brackets; D009969:Orthodontic Wires; D013193:Stainless Steel / Q000737:chemistry*; D013314:Stress, Mechanical; D013499:Surface Properties; D013997:Time Factors; D014087:Tooth Movement Techniques / Q000295:instrumentation*
chemical_list: D003722:Dental Alloys; D020724:Elastomers; D013193:Stainless Steel