title: Response of human osteoblastic and osteoclastic cells to AH plus and pulp canal sealer containing quaternary ammonium polyethylenimine nanoparticles.
abstract: BACKGROUND
  The incorporation of quaternary ammonium polyethylenimine (QPEI) nanoparticles into endodontic sealers induces alterations in their structure and surface properties, which may affect the compatibility with the periapical tissues. This work addressed the behavior of human bone cells exposed to extracts from commercial and QPEI containing AH Plus (DeTrey, Konstanz, Germany) and Pulp Canal Sealer EWT (PCS; Kerr Italia Srl, Salerno, Italy).
  
  
  METHODS
  Freshly mixed AH Plus and PCS or containing 2% QPEI (0.3 mL spread over the well bottom of a 24-well plate) were extracted with culture medium (1.5 mL for 24 hours at 37°C) and diluted (1:20-1:5000). Osteoblastic or osteoclastic cells were cultured in the presence of QPEI particles (1%-10%) and were exposed to the extracts from unmodified and QPEI containing sealers.
  
  
  RESULTS
  QPEI nanoparticles, at 1% and 2%, did not affect cell behavior. On osteoblastic cells, AH Plus and PCS increased DNA at 1:2500 dilution (levels ≤1:100 were cytotoxic). Alkaline phosphatase activity decreased at dilutions ≤1:500. Comparatively, QPEI containing AH Plus increased DNA at 1:2500 and 1:500 dilutions, and QPEI containing PCS induced ALP activity at 1:2500 and 1:500 dilutions. Regarding osteoclastic cells, DNA increased (AH Plus) or was not affected (PCS) at dilutions up to 1:500 and decreased with more concentrated extracts. Tartrate-resistant acid phosphatase activity decreased with dilutions ≤1:500 for both sealers. QPEI containing sealers presented a similar behavior. The sealers affected some intracellular signaling pathways, and QPEI containing sealers further modulate these mechanisms.
  
  
  CONCLUSIONS
  QPEI nanoparticles, at 2%, did not affect cell behavior. However, the incorporation of 2% QPEI particles into AH Plus and PCS modulates the proliferation and differentiation of bone cells, depending on the sealer and the cell type, without increasing the sealers' cytotoxicity.
authors: Department of Endodontics, University of Porto, Porto, Portugal.
authors: Joana
authors: J
authors: Barros
authors: Laboratory for Bone Metabolism and Regeneration, University of Porto, Porto, Portugal; MedInUP-Center for Drug Discovery and Innovative Medicines, University of Porto, Porto, Portugal.
authors: João
authors: J
authors: Costa-Rodrigues
authors: MedInUP-Center for Drug Discovery and Innovative Medicines, University of Porto, Porto, Portugal; Department of Metallurgical and Materials Engineering, University of Porto, Porto, Portugal.
authors: Maria A
authors: MA
authors: Lopes
authors: Department of Endodontics, University of Porto, Porto, Portugal.
authors: Irene
authors: I
authors: Pina-Vaz
authors: Laboratory for Bone Metabolism and Regeneration, University of Porto, Porto, Portugal. Electronic address: mhfernandes@fmd.up.pt.
authors: Maria Helena
authors: MH
authors: Fernandes
mesh_terms: D000135:Acid Phosphatase / Q000187:drug effects; D000469:Alkaline Phosphatase / Q000187:drug effects; D017209:Apoptosis / Q000187:drug effects; D018929:Cell Culture Techniques; D002454:Cell Differentiation / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D004247:DNA / Q000187:drug effects; D004853:Epoxy Resins / Q000494:pharmacology*; D006801:Humans; D007527:Isoenzymes / Q000187:drug effects; D048031:JNK Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors; D020930:MAP Kinase Kinase Kinases / Q000037:antagonists & inhibitors; D008422:Materials Testing; D016328:NF-kappa B / Q000037:antagonists & inhibitors; D053758:Nanoparticles / Q000737:chemistry; D010006:Osteoblasts / Q000187:drug effects*; D010010:Osteoclasts / Q000187:drug effects*; D011094:Polyethyleneimine / Q000494:pharmacology*; D000644:Quaternary Ammonium Compounds / Q000494:pharmacology*; D012387:Root Canal Filling Materials / Q000494:pharmacology*; D015398:Signal Transduction / Q000187:drug effects; D000071681:Tartrate-Resistant Acid Phosphatase; D015035:Zinc Oxide-Eugenol Cement / Q000494:pharmacology*; D048051:p38 Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors
chemical_list: D004853:Epoxy Resins; D007527:Isoenzymes; D016328:NF-kappa B; D000644:Quaternary Ammonium Compounds; D012387:Root Canal Filling Materials; D015035:Zinc Oxide-Eugenol Cement; C534916:epoxy resin-based root canal sealer; C076543:Kerr Pulp Canal Sealer; D011094:Polyethyleneimine; D004247:DNA; D048031:JNK Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D020930:MAP Kinase Kinase Kinases; D000469:Alkaline Phosphatase; D000135:Acid Phosphatase; D000071681:Tartrate-Resistant Acid Phosphatase
keywords: Endodontic sealers; osteoblastic cells; osteoclastic cells; quaternary ammonium polyethylenimine nanoparticles