title: Anchorage miniscrews: a surface characterization study using optical microscopy.
abstract: BACKGROUND
  The aim of this study was to assess the surface changes in orthodontic miniscrew implants retrieved after usage and compare them with brand-new, as-received control miniscrews.
  
  
  METHODS
  The study sample consisted of 28 miniscrews from the same manufacturer: Dual Top Anchor system® (Korea) of different diameters and lengths. One brand-new miniscrew served as a control. Surface characterization was carried out using optical microscopy (Leica DM2500M®) and image magnification (×5, ×10 and ×20).
  
  
  RESULTS
  Observations under optical microscopy showed signs of pitting and crevice corrosion mainly at manufacturing defects. Retrieved miniscrew implants displayed larger surface cracks from corrosive attacks (pitting and crevice). Qualitative sample analysis suggested a loss of gloss and texture, giving the surface a dull appearance. Localized pitting was the most frequent form of corrosion observed in our sample.
  
  
  CONCLUSIONS
  Despite a smooth appearance to the naked eye, the miniscrews all had crack-like surface manufacturing defects. Examination of the surface of these miniscrews, after usage, evidenced pitting or crevice corrosion principally in the area of enhance corrosion resistance.
authors.affiliation: Département d'orthopédie dentofaciale, faculté de médecine dentaire, Casablanca, Morocco.
authors.forename: Mourad
authors.initials: M
authors.lastname: Sebbar
authors.forename: Farid
authors.initials: F
authors.lastname: Bourzgui
authors.forename: Bouchaib
authors.initials: B
authors.lastname: Aazzab
authors.forename: Farid
authors.initials: F
authors.lastname: Elquars
mesh_terms: D000497:Alloys; D001863:Bone Screws; D003343:Corrosion; D003722:Dental Alloys / Q000737:chemistry; D006801:Humans; D008853:Microscopy; D008904:Miniaturization; D052280:Orthodontic Anchorage Procedures / Q000295:instrumentation*; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry
chemical_list: D000497:Alloys; D003722:Dental Alloys; C031462:titanium alloy (TiAl6V4); D014025:Titanium