title: Excretion of dental resin monomers and metabolic intermediates via urine in guinea pigs.
abstract: OBJECTIVE
  Monomers like BisGMA (Bisphenol-A-glycidyldimethacrylate) and comonomers like TEGDMA (triethyleneglycoldimethacrylate) are used in dental restorative materials in order to build up the three-dimensional network of filling materials. Since earlier investigations revealed uptake and subsequent metabolism of unpolymerized remainders of (co)monomers, the present experiment investigates the metabolic urine pattern of guinea pigs (n=4) after application of TEGDMA or BisGMA (each dose=0.02 mmol/kg body weight=100%), respectively.
  
  
  METHODS
  For the investigations BisGMA was pre-dissolved in DMSO and subsequently diluted with 0.9% NaCl solution (final DMSO concentration 1%) and TEGDMA was dissolved in 0.9% NaCl solution. The solutions were administered with a gastric tube into the animals. Control animals received either 0.9% NaCl or 0.9% NaCl solution with 1% DMSO solution.
  
  
  RESULTS
  After 24h in collected urine the following metabolites were identified. After administration of TEGDMA (mean relative concentration of administered substances)+/-s.d. [%]; n=4): unchanged TEGDMA: 12+/-1.5%, MA: 2.4+/-0.8%, and triethyleneglycol: 35+/-2.2%. After administration of BisGMA (mean+/-s.d. [%]; n=4): unchanged BisGMA: 11.4+/-2.7%, MA: 2.2+/-0.6%, and bisphenol-A-bis(2,3-dihydroxypropyl)ether: 60.1+/-5.2%).
  
  
  CONCLUSIONS
  No further metabolites like the previously identified intermediate 2,3-epoxymethacrylic acid and derived reaction products were identified in the urine, indicating that these metabolites must have reacted further.
authors.affiliation: Walther-Straub-Institute of Pharmacology and Toxicology, Ludwig-Maximilians-University of Munich, 80336 Munich, Germany. mario.seiss@gmx.de
authors.forename: Mario
authors.initials: M
authors.lastname: Seiss
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Marquardt
authors.forename: Reinhard
authors.initials: R
authors.lastname: Hickel
authors.forename: Franz-Xaver
authors.initials: FX
authors.lastname: Reichl
mesh_terms: D000818:Animals; D001559:Benzhydryl Compounds; D017438:Bisphenol A-Glycidyl Methacrylate / Q000032:analysis / Q000493:pharmacokinetics; D003188:Composite Resins / Q000493:pharmacokinetics*; D006168:Guinea Pigs; D008297:Male; D008689:Methacrylates / Q000032:analysis / Q000378:metabolism / Q000493:pharmacokinetics; D010636:Phenols / Q000652:urine; D011092:Polyethylene Glycols / Q000032:analysis / Q000378:metabolism / Q000493:pharmacokinetics*; D011109:Polymethacrylic Acids / Q000032:analysis / Q000378:metabolism / Q000493:pharmacokinetics*; D014556:Urine; D000098826:Bisphenol A Compounds
chemical_list: D001559:Benzhydryl Compounds; D017438:Bisphenol A-Glycidyl Methacrylate; D003188:Composite Resins; D008689:Methacrylates; D010636:Phenols; D011092:Polyethylene Glycols; D011109:Polymethacrylic Acids; C519317:2,3-epoxymethacrylic acid; C020946:triethylene glycol dimethacrylate; C006780:bisphenol A; D000098826:Bisphenol A Compounds