title: Antimicrobial and physicochemical properties of experimental light curing composites with alkali-substituted calcium phosphate fillers.
abstract: OBJECTIVE
  The antimicrobial and physicochemical properties of experimental light curing composites prepared with fillers made of mechanically activated alkali-substituted calcium phosphates like CaKPO(4), CaNaPO(4) or Ca(2)KNa(PO(4))(2) were compared with a commercial silane-modified cristobalite filler.
  
  
  METHODS
  The antimicrobial properties were tested using Streptococcus mutans, Staphylococcus aureus and a clinically isolated plaque mixture. The potential for reducing bacteria growth on modified composites was determined using the proliferation reagent WST-1, which enables the measurement of metabolic activity and therefore the colonization with living bacteria. Investigated material properties included the degree of conversion and a test of flexural strength.
  
  
  RESULTS
  All alkali-substituted composites provide a changed, mainly basic micro-milieu leading to a reduction of bacteria population with respect to the non-modified composite of about 25-70% with a flexural strength of cured composites in the range of 55-77 MPa complying with the clinical standard and a degree of conversion of 44-66%.
  
  
  CONCLUSIONS
  This study suggests that the modified composites increase antimicrobial properties while basic composite characteristics are not influenced by the filler.
authors.affiliation: Department for Functional Materials in Medicine and Dentistry, University of Würzburg, Pleicherwall 2, 97070 Würzburg, Germany.
authors.forename: Wolf
authors.initials: W
authors.lastname: Herzlieb
authors.forename: Karolin M
authors.initials: KM
authors.lastname: Köhler
authors.forename: Andrea
authors.initials: A
authors.lastname: Ewald
authors.forename: Norbert
authors.initials: N
authors.lastname: Hofmann
authors.forename: Uwe
authors.initials: U
authors.lastname: Gbureck
mesh_terms: D000890:Anti-Infective Agents / Q000737:chemistry / Q000494:pharmacology*; D002130:Calcium Phosphates / Q000737:chemistry / Q000494:pharmacology*; D003188:Composite Resins / Q000737:chemistry / Q000494:pharmacology*; D003773:Dental Plaque / Q000382:microbiology*; D003799:Dental Stress Analysis; D006801:Humans; D055115:Light-Curing of Dental Adhesives; D008422:Materials Testing; D012821:Silanes / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry / Q000494:pharmacology*; D013211:Staphylococcus aureus / Q000187:drug effects; D013295:Streptococcus mutans / Q000187:drug effects
chemical_list: D000890:Anti-Infective Agents; D002130:Calcium Phosphates; D003188:Composite Resins; D012821:Silanes; D012822:Silicon Dioxide