title: Antibacterial effect of polyethyleneimine nanoparticles incorporated in provisional cements against Streptococcus mutans.
abstract: BACKGROUND
  Frequently provisional restorations require long-term permanence in the oral cavity, thus an antibacterial effect is desirable. We hypothesized that this effect may be achieved by incorporating polyethyleneimine (PEI) nanoparticles into provisional cements.
  
  
  METHODS
  The nanoparticles antibacterial effect incorporated at 0.5%, 1%, and 2% w/w into provisional cement, was studied in vitro. The antibacterial effect against Streptococcus mutans and Enterococcus faecalis was tested using direct contact test. The data was analyzed using the ANOVA test, with the Dunnett test for multiple pairwise comparisons.
  
  
  RESULTS
  A strong antibacterial effect was evident in all test groups after an aging period of 14 days against S. mutans and E. faecalis (p < 0.05). A significant effect was found between study groups 0.5% w/w and 1% w/w group, as well as between study groups 0.5% w/w and 2% w/w for E. faecalis (p < 0.05). No significant difference was found between study groups 1% w/w and 2% w/w. The growth rate graphs depict an effective bacteria inhibition starting from 1% w/w.
  
  
  CONCLUSIONS
  PEI nanoparticles incorporated at low concentrations in a provisional cement exhibit antibacterial effect against S. mutans and E. faecalis for a period of 14 days. The minimum effective concentration suggested is 1% w/w.
  
  
  CONCLUSIONS
  Incorporation of nanoparticles may prevent caries and inflammation, and thereby improve the results of the prosthetic treatment. Further investigation is necessary on the effect on mechanical properties and clinical relevance.
authors.affiliation: Department of Prosthodontics, Faculty of Dentistry, The Hebrew University of Jerusalem, Israel.
authors.forename: Dana Kesler
authors.initials: DK
authors.lastname: Shvero
authors.affiliation: Department of Prosthodontics, Faculty of Dentistry, The Hebrew University of Jerusalem, Israel.
authors.forename: Michael Perez
authors.initials: MP
authors.lastname: Davidi
authors.affiliation: Department of Prosthodontics, Faculty of Dentistry, The Hebrew University of Jerusalem, Israel.
authors.forename: Ervin I
authors.initials: EI
authors.lastname: Weiss
authors.affiliation: Department of Prosthodontics, Faculty of Dentistry, The Hebrew University of Jerusalem, Israel.
authors.forename: Nir
authors.initials: N
authors.lastname: Srerer
authors.affiliation: Department of Prosthodontics, Faculty of Dentistry, The Hebrew University of Jerusalem, Israel.
authors.forename: Nurit
authors.initials: N
authors.lastname: Beyth
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D003738:Dental Cements / Q000737:chemistry* / Q000494:pharmacology; D013293:Enterococcus faecalis / Q000187:drug effects; D006801:Humans; D008422:Materials Testing; D050296:Microbial Viability / Q000187:drug effects; D053758:Nanoparticles / Q000737:chemistry / Q000627:therapeutic use; D011094:Polyethyleneimine / Q000494:pharmacology* / Q000627:therapeutic use; D013295:Streptococcus mutans / Q000187:drug effects*
chemical_list: D000900:Anti-Bacterial Agents; D003738:Dental Cements; D011094:Polyethyleneimine