title: Biofilm medium leads to apatite formation on bioactive surfaces.
abstract: OBJECTIVE
  When investigating apatite formation on biomaterial surfaces, simulated body fluid (SBF) is used as an in vitro solution, however, it does not provide an appropriate environment for the growth of bacterial biofilm. The aim of the present study was to compare the bioactivity in terms of apatite formation on two bioactive glass (BAG) composite surfaces using both SBF and bacterial-biofilm growing medium (BM).
  
  
  METHODS
  Polymer composite substrates with different percentages of BAG-particles (50% and 75% by weight) were prepared. Plain resin substrates were used as a negative control. The substrates were immersed in SBF and BM for 3 days. The surface and, subsequently, the cross-sections of the substrates were examined with scanning electron microscopy (SEM) and x-ray energy dispersive spectroscopy (EDS).
  
  
  RESULTS
  All the investigated BAG-composite surfaces showed apatite formation after immersion in SBF and BM liquid media.
  
  
  CONCLUSIONS
  The use of BM is a promising method for studies involving simultaneous biofilm growth and apatite formation on bioactive surfaces.
authors.affiliation: Department of Periodontology, Institute of Dentistry, University of Turku, Turku - Finland and Turku Clinical Biomaterials Centre - TCBC, University of Turku, Turku - Finland.
authors.forename: Julia
authors.initials: J
authors.lastname: Kulkova
authors.forename: Aous A
authors.initials: AA
authors.lastname: Abdulmajeed
authors.forename: Eija
authors.initials: E
authors.lastname: Könönen
authors.forename: Timo O
authors.initials: TO
authors.lastname: Närhi
mesh_terms: D001031:Apatites / Q000737:chemistry / Q000378:metabolism*; D001419:Bacteria / Q000254:growth & development; D001672:Biocompatible Materials / Q000378:metabolism; D018441:Biofilms; D001826:Body Fluids / Q000502:physiology; D002516:Ceramics / Q000737:chemistry / Q000378:metabolism*; D003470:Culture Media / Q000494:pharmacology*; D006801:Humans; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D013052:Spectrometry, X-Ray Emission; D013499:Surface Properties
chemical_list: D001031:Apatites; D001672:Biocompatible Materials; C022107:Bioglass; D003470:Culture Media