title: The adhesion of oral bacteria to modified titanium surfaces: role of plasma proteins and electrostatic forces.
abstract: OBJECTIVE
  Modifications of titanium (Ti) implant surfaces have a significant effect on early biofilm formation and the outcome of implant procedures. The aim of this study was to examine the role of plasma proteins and electrostatic forces in the adhesion mechanism of oral bacteria to modified Ti surfaces.
  
  
  METHODS
  Ti discs with three different types of surface modifications, machined, acid-etched, and acid-etched and blasted, were examined for adhesion of oral bacteria: Streptococcus mutans, Porphyromonas gingivalis, and Fusobacterium nucleatum. Following pretreatment of the Ti with ion rich solutions or coating by human serum albumin or fibronectin, bacterial adhesion was examined by scanning electron microscopy and assessed quantitatively by DNA analysis. Ti coating by proteins as well as bacterial adhesion and their interrelationships were further investigated through confocal scanning laser microscopy.
  
  
  RESULTS
  Acid-etched and blasted Ti surfaces exhibited significantly higher amounts of bacteria adhesion than the other two surfaces. Calcium was found to serve as a bridging agent in the adhesion process of S. mutans and F. nucleatum to Ti surfaces. Although albumin coating of the Ti reduced the adhesion of S. mutans to all surfaces, it had no influence on the adhesion of P. gingivalis or F. nucleatum. Coating the Ti with fibronectin enhanced P. gingivalis and F. nucleatum adhesion.
  
  
  CONCLUSIONS
  Bacterial adhesion to Ti surfaces is roughness-dependent, and the adhesion mechanism is influenced by ions and proteins of the initial coating derived from the blood.
authors.affiliation: Oral Microbiology and Ecology Lab, Betty and Walter Cohen Chair for Periodontal Research, The Hebrew, Jerusalem, Israel. liad.badihi@mail.huji.ac.il
authors.forename: Liad
authors.initials: L
authors.lastname: Badihi Hauslich
authors.forename: Michael N
authors.initials: MN
authors.lastname: Sela
authors.forename: Doron
authors.initials: D
authors.lastname: Steinberg
authors.forename: Graciela
authors.initials: G
authors.lastname: Rosen
authors.forename: David
authors.initials: D
authors.lastname: Kohavi
mesh_terms: D000134:Acid Etching, Dental; D001422:Bacterial Adhesion; D001798:Blood Proteins / Q000502:physiology*; D015921:Dental Implants / Q000382:microbiology; D016967:Fusobacterium nucleatum; D018613:Microscopy, Confocal; D008855:Microscopy, Electron, Scanning; D016966:Porphyromonas gingivalis; D055672:Static Electricity; D013295:Streptococcus mutans; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*
chemical_list: D001798:Blood Proteins; D015921:Dental Implants; D014025:Titanium