title: Effect of Air-Polishing on Titanium Surfaces, Biofilm Removal, and Biocompatibility: A Pilot Study.
abstract: OBJECTIVE
  The aims of this in vitro study were to evaluate morphological changes induced by glycine powder air-polishing on titanium surfaces, biofilm removal, and biocompatibility.
  
  
  METHODS
  Titanium grade IV discs were allocated into two groups: (1) discs without biofilm and (2) discs for Streptococcus mutans biofilm formation. Discs in each group were further subdivided into (a) no treatment and (b) air-polishing treatment with glycine powder. Discs were characterized by scanning electron microscopy (SEM), electron-dispersive spectroscopy (EDS), and confocal microscopy. Bacterial biofilms were quantified using a crystal violet dye-binding assay. Biocompatibility was evaluated by measuring the coverage and viability of L929 fibroblast cells cultured on the discs.
  
  
  RESULTS
  Air-polishing increased the roughness of treated discs (P < 0.05). EDS analysis did not show significant differences in the chemical composition of treated and nontreated discs. The amount of residual biofilm on treated discs was 8.6-fold lower than untreated controls (P < 0.05). Coverage of treated discs by fibroblasts was half that of untreated discs (P < 0.05) although both groups had the same cell viability.
  
  
  CONCLUSIONS
  Air-polishing removed a significant amount of biofilm from titanium surfaces. The "polishing" was accompanied by increased surface roughness, but there were no changes in chemical and elemental compositions, nor the biocompatibility.
authors.affiliation: Sir John Walsh Research Institute, University of Otago, Dunedin 9016, New Zealand.
authors.forename: Vincent
authors.initials: V
authors.lastname: Bennani
authors.affiliation: Sir John Walsh Research Institute, University of Otago, Dunedin 9016, New Zealand.
authors.forename: Linda
authors.initials: L
authors.lastname: Hwang
authors.affiliation: Sir John Walsh Research Institute, University of Otago, Dunedin 9016, New Zealand.
authors.forename: Andrew
authors.initials: A
authors.lastname: Tawse-Smith
authors.affiliation: Department of Anatomy, University of Otago, Dunedin 9016, New Zealand.
authors.forename: George J
authors.initials: GJ
authors.lastname: Dias
authors.affiliation: Sir John Walsh Research Institute, University of Otago, Dunedin 9016, New Zealand.
authors.forename: Richard D
authors.initials: RD
authors.lastname: Cannon
mesh_terms: D000818:Animals; D018441:Biofilms; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D005998:Glycine / Q000737:chemistry* / Q000633:toxicity; D008422:Materials Testing; D051379:Mice; D010865:Pilot Projects; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*
chemical_list: D014025:Titanium; D005998:Glycine