title: Influence of root canal disinfectants on growth factor release from dentin.
abstract: BACKGROUND
  During dentinogenesis, growth factors become entrapped in the dentin matrix that can later be released by demineralization. Their effect on pulpal stem cell migration, proliferation, and differentiation could be beneficial for regenerative endodontic therapies. However, precondition for success, as for conventional root canal treatment, will be sufficient disinfection of the root canal system. Various irrigation solutions and intracanal dressings are available for clinical use. The aim of this study was 2-fold: to identify a demineralizing solution suitable for growth factor release directly from dentin and to evaluate whether commonly used disinfectants for endodontic treatment will compromise this effect.
  
  
  METHODS
  Dentin disks were prepared from extracted human teeth and treated with EDTA or citric acid at different concentrations or pH for different exposure periods. The amount of transforming growth factor-β1 (TGF-β1), fibroblast growth factor 2, and vascular endothelial growth factor were quantified via enzyme-linked immunosorbent assay and visualized by gold labeling. Subsequently, different irrigation solutions (5.25% sodium hypochloride, 0.12% chlorhexidine digluconate) and intracanal dressings (corticoid-antibiotic paste, calcium hydroxide: water-based and oil-based, triple antibiotic paste, chlorhexidine gel) were tested, and the release of TGF-β1 was measured after a subsequent conditioning step with EDTA.
  
  
  RESULTS
  Conditioning with 10% EDTA at pH 7 rendered the highest amounts of TGF-β1 among all test solutions. Fibroblast growth factor 2 and vascular endothelial growth factor were detected after EDTA conditioning at minute concentrations. Irrigation with chlorhexidine before EDTA conditioning increased TGF-β1 release; sodium hypochloride had the opposite effect. All tested intracanal dressings interfered with TGF-β1 release except water-based calcium hydroxide.
  
  
  CONCLUSIONS
  Growth factors can be released directly from dentin via EDTA conditioning. The use of disinfecting solutions or medicaments can amplify or attenuate this effect.
authors.affiliation: Department of Operative Dentistry and Periodontology, University of Regensburg, Regensburg, Germany. Electronic address: kerstin.galler@ukr.de.
authors.forename: Kerstin M
authors.initials: KM
authors.lastname: Galler
authors.affiliation: Department of Operative Dentistry and Periodontology, University of Regensburg, Regensburg, Germany.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Buchalla
authors.affiliation: Department of Operative Dentistry and Periodontology, University of Regensburg, Regensburg, Germany.
authors.forename: Karl-Anton
authors.initials: KA
authors.lastname: Hiller
authors.affiliation: Department of Operative Dentistry and Periodontology, University of Regensburg, Regensburg, Germany.
authors.forename: Marianne
authors.initials: M
authors.lastname: Federlin
authors.affiliation: Department of Operative Dentistry and Periodontology, University of Regensburg, Regensburg, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Eidt
authors.affiliation: Department of Operative Dentistry and Periodontology, University of Regensburg, Regensburg, Germany.
authors.forename: Mona
authors.initials: M
authors.lastname: Schiefersteiner
authors.affiliation: Department of Operative Dentistry and Periodontology, University of Regensburg, Regensburg, Germany; Department of Preventive, Restorative and Pediatric Dentistry, School of Dental Medicine, University of Bern, Bern, Switzerland.
authors.forename: Gottfried
authors.initials: G
authors.lastname: Schmalz
mesh_terms: D003804:Dentin / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D004202:Disinfectants / Q000494:pharmacology*; D004492:Edetic Acid / Q000494:pharmacology; D016222:Fibroblast Growth Factor 2 / Q000378:metabolism; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000378:metabolism*; D012388:Root Canal Irrigants / Q000494:pharmacology*; D012996:Solutions; D053773:Transforming Growth Factor beta1 / Q000378:metabolism; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism
chemical_list: D004202:Disinfectants; D036341:Intercellular Signaling Peptides and Proteins; D012388:Root Canal Irrigants; D012996:Solutions; D053773:Transforming Growth Factor beta1; D042461:Vascular Endothelial Growth Factor A; D016222:Fibroblast Growth Factor 2; D004492:Edetic Acid
keywords: Dentin; growth factors; intracanal dressing; irrigation solutions; regenerative endodontics