title: Bacterial adhesion on commercially pure titanium and zirconium oxide disks: an in vivo human study.
abstract: BACKGROUND
  Little is known about the mechanisms of bacterial interaction with implant materials in the oral cavity. A correlation between plaque accumulation and progressive bone loss around implants has been reported. Bacterial adhesion shows a direct positive correlation with surface roughness. Other surface characteristics also seem to be extremely important with regard to plaque formation. Different adhesion affinities of bacteria have been reported for different materials. The aim of this study was to characterize the percentage of surface covered by bacteria on commercially pure titanium and zirconium oxide disks.
  
  
  METHODS
  Ten patients participated in this study. A removable acrylic device was adapted to the molar-premolar region, and commercially pure titanium (control) and zirconium oxide (test) disks were glued to the buccal aspect of each device. The surface roughness of titanium and test specimens was similar. After 24 hours, all disks were removed and processed for scanning electron microscopy, for the evaluation of the portion of surface covered by bacteria.
  
  
  RESULTS
  In control specimens, the area covered by bacteria was 19.3% +/- 2.9; in test specimens, the area was 12.1% +/- 1.96. The disk surface covered by bacteria on test specimens was significantly lower than that of control specimens (P = 0.0001).
  
  
  CONCLUSIONS
  Our results demonstrate that zirconium oxide may be a suitable material for manufacturing implant abutments with a low colonization potential.
authors.affiliation: Dental School, University of Chieti, Chieti, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Scarano
authors.forename: Maurizio
authors.initials: M
authors.lastname: Piattelli
authors.forename: Sergio
authors.initials: S
authors.lastname: Caputi
authors.forename: Gian Antonio
authors.initials: GA
authors.lastname: Favero
authors.forename: Adriano
authors.initials: A
authors.lastname: Piattelli
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001419:Bacteria / Q000145:classification / Q000648:ultrastructure; D001422:Bacterial Adhesion; D003764:Dental Materials / Q000737:chemistry*; D006801:Humans; D008855:Microscopy, Electron, Scanning; D012471:Salivary Proteins and Peptides / Q000648:ultrastructure; D013499:Surface Properties; D013997:Time Factors; D014025:Titanium / Q000737:chemistry*; D015040:Zirconium / Q000737:chemistry*
chemical_list: D003764:Dental Materials; D012471:Salivary Proteins and Peptides; D015040:Zirconium; D014025:Titanium; C028541:zirconium oxide