title: Cytotoxicity and induction of DNA double-strand breaks by components leached from dental composites in primary human gingival fibroblasts.
abstract: BACKGROUND
  The public interest steadily increases in the biological adverse effects caused by components released from resin-based dental restorations.
  
  
  OBJECTIVE
  In this study, the cytotoxicity and the genotoxicity were investigated of following released components from dental resin restorations in human gingival fibroblasts (HGF): tetraethyleneglycol dimethacrylate (TEEGDMA), neopentylglycol dimethacrylate (Neopen), diphenyliodoniumchloride (DPIC), triphenyl-stibane (TPSB) and triphenylphosphane (TPP).
  
  
  METHODS
  XTT based cell viability assay was used for cytotoxicity screening of substances. γ-H2AX assay was used for genotoxicity screening. In the γ-H2AX assay, HGFs were exposed to the substances for 6h. Induced foci represent double DNA strand breaks (DSBs), which can induce ATM-dependent phosphorylation of the histone H2AX. Cell death effects (apoptosis and necrosis), induced by the substances were visually tested by the same investigator using the fluorescent microscope.
  
  
  RESULTS
  All tested substances induced a dose-dependent loss of viability in HGFs. Following toxicity ranking among the substances at EC50-concentration were found in the XTT assay (mM, mean±SEM; n=5): DPIC>Neopen>TPSB>TPP>TEEGDMA. DSB-foci per HGF-cell were obtained, when HGFs were exposed to the EC50-concentration of each substance in the following order (mean±SEM; n=3): DPIC>Neopen>TPSB>TPP>TEEGDMA. Multi-foci cells (cells that contain more than 40 foci each) in 80 HGF-cells at EC50-concentration of each substance were found as follow (mean±SEM; n=3): DPIC>Neopen>TPP>TPSB>TEEGDMA. Cell apoptosis contained in each substance at EC50-concentration in the following order (mean±SEM; n=3): DPIC>Neopen>TPSB>TPP >TEEGDMA. Cell necrosis contained in each substance at EC50-concentration in the following order (mean±SEM; n=3): DPIC>Neopen>TPSB>TPP>TEEGDMA.
  
  
  CONCLUSIONS
  Leached components from dental resin restorations can induce DNA DSBs and cell death effects in HGFs.
authors.affiliation: Department of Operative/Restorative Dentistry, Periodontology and Pedodontics, Ludwig-Maximilians-University of Munich, Goethestr. 70, 80336 Munich, Germany. m.shehata@campus.lmu.de
authors.forename: Mohamed
authors.initials: M
authors.lastname: Shehata
authors.forename: Jürgen
authors.initials: J
authors.lastname: Durner
authors.forename: Ayce
authors.initials: A
authors.lastname: Eldenez
authors.forename: Kirsten
authors.initials: K
authors.lastname: Van Landuyt
authors.forename: Panorea
authors.initials: P
authors.lastname: Styllou
authors.forename: Lena
authors.initials: L
authors.lastname: Rothmund
authors.forename: Reinhard
authors.initials: R
authors.lastname: Hickel
authors.forename: Harry
authors.initials: H
authors.lastname: Scherthan
authors.forename: Werner
authors.initials: W
authors.lastname: Geurtsen
authors.forename: Bernd
authors.initials: B
authors.lastname: Kaina
authors.forename: Thomas
authors.initials: T
authors.lastname: Carell
authors.forename: Franz X
authors.initials: FX
authors.lastname: Reichl
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D001713:Biphenyl Compounds / Q000633:toxicity; D018929:Cell Culture Techniques; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D003188:Composite Resins / Q000633:toxicity*; D053903:DNA Breaks, Double-Stranded / Q000187:drug effects*; D003764:Dental Materials / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D005347:Fibroblasts / Q000187:drug effects*; D005881:Gingiva / Q000166:cytology / Q000187:drug effects*; D006657:Histones / Q000187:drug effects; D006801:Humans; D007202:Indicators and Reagents; D008422:Materials Testing; D008689:Methacrylates / Q000633:toxicity; D008856:Microscopy, Fluorescence; D009153:Mutagens / Q000633:toxicity; D009336:Necrosis; D009861:Onium Compounds / Q000633:toxicity; D009943:Organophosphorus Compounds / Q000633:toxicity; D011092:Polyethylene Glycols / Q000633:toxicity; D011109:Polymethacrylic Acids / Q000633:toxicity; D013267:Stilbenes / Q000633:toxicity; D013778:Tetrazolium Salts
chemical_list: D001713:Biphenyl Compounds; D003188:Composite Resins; D003764:Dental Materials; C468783:H2AX protein, human; D006657:Histones; D007202:Indicators and Reagents; D008689:Methacrylates; D009153:Mutagens; D009861:Onium Compounds; D009943:Organophosphorus Compounds; D011109:Polymethacrylic Acids; D013267:Stilbenes; D013778:Tetrazolium Salts; C031291:diphenyliodonium; C059087:2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-((phenylamino)carbonyl)-2H-tetrazolium hydroxide; C020946:triethylene glycol dimethacrylate; C038017:neopentyl methacrylate; C061896:triphenylphosphine; D011092:Polyethylene Glycols; C002428:estrobin
keywords: Composite; DPIC; HGF; Neopen; TEEGMA; TPP; TPSB; γ-H2AX assay