title: Real-time xCELLigence impedance analysis of the cytotoxicity of dental composite components on human gingival fibroblasts.
abstract: OBJECTIVE
  Aim of this study was by continuous monitoring to assay the proliferative capacity of human gingival fibroblasts (HGFs), to investigate cytotoxicity of the most common monomers/comonomers in dental resin composites: bisphenol-A-glycidylmethacrylate (BisGMA), hydroxyethylenemethacrylate (HEMA), triethyleneglycoldimethacrylate (TEGDMA), and urethanedimethacrylate (UDMA) in HGFs during 24h exposure using the xCELLigence system.
  
  
  METHODS
  xCELLigence cell index (CI) impedance measurements were performed according to the instructions of the supplier. HGFs were resuspended in medium and subsequently adjusted to 400,000, 200,000, 100,000, and 50,000 cells/mL. After seeding 100 microL of the cell suspensions into the wells of the E-plate 96, HGFs were monitored every 15 min for a period of up to 18 h by the xCELLigence system.
  
  
  RESULTS
  Half maximum effect concentrations (EC(50)) were determined based on the dose-response curves derived by xCELLigence measurements. Following real-time analysis, significantly increased EC(50) values of HGFs exposed for 24h to the following substances were obtained: HEMA(a), TEGDMA(b), UDMA(c). The EC(50) values (mean [mmol/L]+/-S.E.M.; n=5) were: HEMA 11.20+/-0.3, TEGDMA(a) 3.61+/-0.2, UDMA(a,b) 0.20+/-0.1, and BisGMA(a,b,c) 0.08+/-0.1. These results are similar to the EC(50) values previously observed with the XTT end-point assay.
  
  
  CONCLUSIONS
  Our data suggests that the xCELLigence live cell analysis system offers dynamic live cell monitoring and combines high data acquisition rates with ease of handling. Therefore, the xCELLigence system can be used as a rapid monitoring tool for cellular viability and be applied in toxicity testing of xenobiotics using in vitro cell cultures.
authors.affiliation: Walther-Straub-Institute of Pharmacology and Toxicology, Ludwig-Maximilians-University of Munich, Nussbaumstrasse 26, D-80336 Munich, Germany. ebru_urcan@yahoo.com
authors.forename: Ebru
authors.initials: E
authors.lastname: Urcan
authors.forename: Ursula
authors.initials: U
authors.lastname: Haertel
authors.forename: Marianthi
authors.initials: M
authors.lastname: Styllou
authors.forename: Reinhard
authors.initials: R
authors.lastname: Hickel
authors.forename: Harry
authors.initials: H
authors.lastname: Scherthan
authors.forename: Franz Xaver
authors.initials: FX
authors.lastname: Reichl
mesh_terms: D017438:Bisphenol A-Glycidyl Methacrylate / Q000008:administration & dosage / Q000633:toxicity; D002448:Cell Adhesion / Q000187:drug effects; D018929:Cell Culture Techniques; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D003188:Composite Resins / Q000008:administration & dosage / Q000633:toxicity*; D003764:Dental Materials / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D017097:Electric Impedance; D055724:Electrophysiological Phenomena; D005347:Fibroblasts / Q000187:drug effects*; D005881:Gingiva / Q000166:cytology / Q000187:drug effects*; D006801:Humans; D008689:Methacrylates / Q000008:administration & dosage / Q000633:toxicity; D011092:Polyethylene Glycols / Q000008:administration & dosage / Q000633:toxicity; D011109:Polymethacrylic Acids / Q000008:administration & dosage / Q000633:toxicity; D011140:Polyurethanes / Q000008:administration & dosage / Q000633:toxicity; D013997:Time Factors
chemical_list: D003188:Composite Resins; D003764:Dental Materials; D008689:Methacrylates; D011109:Polymethacrylic Acids; D011140:Polyurethanes; C029824:urethane dimethacrylate luting resin; C020946:triethylene glycol dimethacrylate; D011092:Polyethylene Glycols; D017438:Bisphenol A-Glycidyl Methacrylate; C005044:hydroxyethyl methacrylate