title: Mini-implants for Orthodontic Anchorage: Surface Analysis after Redrilling and Sterilization - An in vitro Study.
abstract: OBJECTIVE
  This study aimed to investigate, in vitro, possible alterations on mini-implants surface after retrieval and if the cleaning process and sterilization can predispose damages.
  
  
  METHODS
  Two commercial mini-implants were tested for deformations after drilling and removing in artificial bone four times. Samples were analyzed by scanning electron microscopy, and surface alterations verified through thread and pitches deformation. To alterations caused by insertion/removal and the cleaning process and sterilization were verified in different procedures: Insertions and sterilization, only insertions, and only sterilization. Photomicrographs were analyzed in order to compare the surface characteristics. Head deformation was verified qualitatively. For a quantitative analysis, distances between threads were measured across the active part of the mini-implants.
  
  
  RESULTS
  No deformation was observed in both groups. The cleaning and sterilization processes did not provoke alteration in both groups. Nevertheless, the presence of synthetic bone was noted in some samples. The mean distances between implant threads were similar after all steps in all regions in both groups.
  
  
  CONCLUSIONS
  The results suggest that the tested mini-implants can be retrieved without damage of its surface after four cycles of insertion, removal, and sterilization.
  
  
  BACKGROUND
  Orthodontic mini-implant, Redrilling, Sterilization.
  
  
  CONCLUSIONS
  Mini-implants can be retrieved without damage to its surface after four cycles of insertion, removal, and sterilization in the same patient without representing a biological concern.
authors.affiliation: Department of Orthodontics, Faculdade IPPEO, Curitiba Parana, Brazil.
authors.forename: J M
authors.initials: JM
authors.lastname: Gross
authors.affiliation: Postgraduate Program in Dentistry, Federal University of Pelotas, Pelotas, Rio Grande do Sul, Brazil.
authors.forename: G G
authors.initials: GG
authors.lastname: Nascimento
authors.affiliation: Instituto e Centro de Pesquisas Sao Leopoldo Mandic Campinas, Sao Paulo, Brazil.
authors.forename: V C
authors.initials: VC
authors.lastname: Araújo
authors.affiliation: School of Dentistry, University of Sao Paulo, Sao Paulo, Brazil.
authors.forename: Mjs
authors.initials: M
authors.lastname: Bönecker
authors.affiliation: Assistant Professor, School of Dentistry, Sao Paulo State University, CEP 16015-050 Rua Jose Bonifacio Aracatuba, Sao Paulo, Brazil, Phone: +551836363200, e-mail: cfuruse@foa.unesp.br.
authors.forename: C
authors.initials: C
authors.lastname: Furuse
mesh_terms: D015921:Dental Implants; D006801:Humans; D008855:Microscopy, Electron, Scanning; D052280:Orthodontic Anchorage Procedures / Q000379:methods*; D010784:Photomicrography; D013242:Sterilization; D013499:Surface Properties
chemical_list: D015921:Dental Implants