title: Interaction of chlorhexidine with smooth and rough types of titanium surfaces.
abstract: BACKGROUND
  Chlorhexidine (CHX) digluconate exerts plaque inhibitory efficacy in the natural dentition environment due to a superior degree of persistence at the tooth surface. The purpose of the present study was to assess the interaction of CHX with titanium surfaces to estimate its antiplaque potential in the peri-implant environment.
  
  
  METHODS
  Saliva-coated machined smooth (S) and sand-blasted acid-etched rough (R) titanium disks were soaked in either 0.1% or 0.2% CHX solution. After 24 hours, CHX amounts that were adsorbed, washed out, and desorbed from the titanium surfaces were determined spectrophotometrically at 230 nm. The antibacterial activity of CHX-treated titanium disks was assessed by measuring bacterial inhibition zones on Streptococcus mutans lawns.
  
  
  RESULTS
  Titanium disks adsorbed 3% to 8% of the available CHX, which was significantly higher with 0.2% CHX (P<0.001) than with 0.1% CHX and two-fold higher on the R titanium disks compared to S titanium surface (P<0.001). After rinsing with water, 2.2% of the adsorbed CHX was washed out. Over 24 hours, S- and R-type disks released 1.1% and 0.6% of the adsorbed agent, respectively. Larger bacterial inhibition zones were obtained with 0.2% CHX and in R disks compared to S disks.
  
  
  CONCLUSIONS
  CHX displayed persistence at the titanium surface. The adsorption level and bacterial growth inhibition were affected by CHX concentration and titanium surface characteristics, with higher levels of adsorption and antibacterial activity with 0.2% CHX and rough titanium surface. The slow CHX release rate suggests persistence of this agent at the titanium-pellicle surface, which can provide a long-term antiplaque effect.
authors.affiliation: Department of Periodontology, The Maurice and Gabriela Goldschleger School of Dental Medicine, Tel Aviv University, Tel Aviv, Israel. kavital@post.tau.ac.il
authors.forename: Avital
authors.initials: A
authors.lastname: Kozlovsky
authors.forename: Zvi
authors.initials: Z
authors.lastname: Artzi
authors.forename: Ofer
authors.initials: O
authors.lastname: Moses
authors.forename: Nurit
authors.initials: N
authors.lastname: Kamin-Belsky
authors.forename: Ronit Bar-Ness
authors.initials: RB
authors.lastname: Greenstein
mesh_terms: D000327:Adsorption; D000704:Analysis of Variance; D000891:Anti-Infective Agents, Local / Q000737:chemistry* / Q000494:pharmacology; D002710:Chlorhexidine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000494:pharmacology; D044622:Dental Pellicle; D006801:Humans; D013295:Streptococcus mutans / Q000187:drug effects; D013499:Surface Properties; D014025:Titanium
chemical_list: D000891:Anti-Infective Agents, Local; D014025:Titanium; C010882:chlorhexidine gluconate; D002710:Chlorhexidine