title: Biofilm formation within the interface of bovine root dentin treated with conjugated chitosan and sealer containing chitosan nanoparticles.
abstract: BACKGROUND
  The purpose of this study was to assess biofilm formation within sealer-dentin interfaces of root segments filled with gutta-percha and sealer incorporated with chitosan (CS) nanoparticles with and without canal surface treatment with different formulations of CS.
  
  
  METHODS
  Standardized canals of 4-mm bovine root segments (N = 35) were filled with gutta-percha and pulp canal sealer incorporated with CS nanoparticles without surface treatment (group CS) or after surface treatment with phosphorylated CS (group PHCS), CS-conjugated rose bengal and photodynamic irradiation (group CSRB), or a combination of both PHCS and CSRB (group RBPH). The control group was filled with gutta-percha and an unmodified sealer. After 7 days of setting, specimens were aged in buffered solution at 37°C for 1 or 4 weeks. Monospecies biofilms of Enterococcus faecalis were grown on specimens for 7 days in a chemostat-based biofilm fermentor. Biofilm formation within the sealer-dentin interface was assessed with confocal laser scanning microscopy.
  
  
  RESULTS
  In the 4-week-aged specimens only, the mean biofilm areas were significantly smaller than in the control for the CS (P = .008), PHCS (P = .012), and RBPH (P = .034) groups. The percentage of the biofilm-covered interface also was significantly lower than in the control for the CS (P = .024) and PHCS (P = .003) groups. The CS, PHCS, and RBPH groups did not differ significantly.
  
  
  CONCLUSIONS
  Incorporating CS nanoparticles into the zinc oxide-eugenol sealer inhibited biofilm formation within the sealer-dentin interface. This effect was maintained when canals were treated with phosphorylated CS, and it was moderated by canal treatment with CS-conjugated rose bengal and irradiation.
authors: Discipline of Endodontics, Faculty of Dentistry, University of Toronto, Toronto, Ontario, Canada.
authors: Luis
authors: L
authors: DaSilva
authors: Yoav
authors: Y
authors: Finer
authors: Shimon
authors: S
authors: Friedman
authors: Bettina
authors: B
authors: Basrani
authors: Anil
authors: A
authors: Kishen
mesh_terms: D000818:Animals; D000891:Anti-Infective Agents, Local / Q000627:therapeutic use*; D018441:Biofilms / Q000187:drug effects / Q000254:growth & development*; D002021:Buffers; D002417:Cattle; D048271:Chitosan / Q000627:therapeutic use*; D003094:Collagen / Q000187:drug effects; D003804:Dentin / Q000187:drug effects / Q000382:microbiology*; D013293:Enterococcus faecalis / Q000187:drug effects / Q000254:growth & development; D006171:Gutta-Percha / Q000627:therapeutic use; D008422:Materials Testing; D018613:Microscopy, Confocal; D008855:Microscopy, Electron, Scanning; D053758:Nanoparticles / Q000627:therapeutic use*; D010778:Photochemotherapy; D017319:Photosensitizing Agents / Q000627:therapeutic use; D012387:Root Canal Filling Materials / Q000627:therapeutic use*; D012395:Rose Bengal / Q000627:therapeutic use; D013499:Surface Properties; D013696:Temperature; D013997:Time Factors; D014092:Tooth Root / Q000187:drug effects / Q000382:microbiology*; D015035:Zinc Oxide-Eugenol Cement / Q000627:therapeutic use
chemical_list: D000891:Anti-Infective Agents, Local; D002021:Buffers; D017319:Photosensitizing Agents; D012387:Root Canal Filling Materials; D015035:Zinc Oxide-Eugenol Cement; D012395:Rose Bengal; D006171:Gutta-Percha; D003094:Collagen; D048271:Chitosan