title: Salivary protein adsorption and Streptococccus gordonii adhesion to dental material surfaces.
abstract: OBJECTIVE
  The initial adhesion of microorganisms to clinically used dental biomaterials is influenced by physico-chemical parameters like hydrophobicity and pre-adsorption of salivary proteins. Here, polymethyl methacrylate (PMMA), polyethylene (PE), polytetrafluoroethylene (PTFE), silicone (Mucopren soft), silorane-based (Filtek Silorane) and methacrylate-based (Tetric EvoCeram) dental composites, a conventional glassionomer cement as well as cobalt-chromium-molybdenum (Co28Cr6Mo) and titanium (Ti6Al4V) were tested for adsorption of salivary proteins and adhesion of Streptococcus gordonii DL1.
  
  
  METHODS
  Wettability of material surfaces precoated with salivary proteins or left in phosphate-buffered saline was determined by the measurement of water contact angles. Amounts of adsorbed proteins were determined directly on material surfaces after biotinylation of amino groups and detection by horseradish peroxidase-conjugated avidin-D. The same technique was used to analyze for the binding of biotinylated bacteria to material surfaces.
  
  
  RESULTS
  The highest amount of proteins (0.18μg/cm(2)) adsorbed to hydrophobic PTFE samples, and the lowest amount (0.025μg/cm(2)) was detected on silicone. The highest number of S. gordonii (3.2×10(4)CFU/mm(2)) adhered to the hydrophilic glassionomer cement surface coated with salivary proteins, and the lowest number (4×10(3)CFU/mm(2)) was found on the hydrophobic silorane-based composite. Hydrophobicity of pure material surfaces and the number of attached microorganisms were weakly negatively correlated. No such correlation between hydrophobicity and the number of bacteria was detected when surfaces were coated with salivary proteins.
  
  
  CONCLUSIONS
  Functional groups added by the adsorption of specific salivary proteins to material surfaces are more relevant for initial bacterial adhesion than hydrophobicity as a physical property.
authors: Department of Operative Dentistry and Periodontology, University of Regensburg Medical Centre, 93042 Regensburg, Germany. Electronic address: helmut.schweikl@klinik.uni-regensburg.de.
authors: Helmut
authors: H
authors: Schweikl
authors: Karl-Anton
authors: KA
authors: Hiller
authors: Ulrich
authors: U
authors: Carl
authors: Rainer
authors: R
authors: Schweiger
authors: Andreas
authors: A
authors: Eidt
authors: Stefan
authors: S
authors: Ruhl
authors: Rainer
authors: R
authors: Müller
authors: Gottfried
authors: G
authors: Schmalz
mesh_terms: D000327:Adsorption; D001422:Bacterial Adhesion; D003764:Dental Materials; D054773:Streptococcus gordonii / Q000502:physiology*
chemical_list: D003764:Dental Materials
keywords: Bacterial adhesion; Dental materials; Protein absorption; Saliva