title: Effect of Opalescence(®) bleaching gels on the elution of bulk-fill composite components.
abstract: OBJECTIVE
  Bleaching treatments can affect release of components from conventional composites. In this continuing study the influence of two different bleaching gels on the elution of bulk-fill composite components was investigated.
  
  
  METHODS
  The composites Tetric EvoCeram(®) Bulk Fill, QuiXFil™ and X-tra fil were treated with the bleaching gels Opalescence PF 15% (PF 15%) for 5 h and PF 35% (PF 35%) for 30 min and then stored in methanol and water for 24 h and 7 d. The eluates were analyzed by gas chromatography/mass spectrometry (GC/MS). Unbleached specimens were used as control group.
  
  
  RESULTS
  A total of 7 different elutable substances have been identified from the investigated composites after bleaching-treatment. Three of them were methacrylates: 2-hydroxyethyl methacrylate (HEMA), triethylene glycol dimethacrylate (TEGDMA) and trimethylolpropane trimethacrylate (TMPTMA). Compared to the unbleached controls an increase in elution after PF 15%-treatment of following compounds was found: HEMA (Tetric EvoCeram(®) Bulk Fill), TEGDMA (QuiXFil™, X-tra fil) and 4-N,N-dimethylaminobenzoic acid butyl ethoxy ester (DMABEE) (Tetric EvoCeram(®) Bulk Fill, QuiXFil™, X-tra fil). Following compounds showed a reduction in elution after PF 35%-treatment compared to controls: TEGDMA (QuiXFil™) and DMABEE (Tetric EvoCeram(®) Bulk Fill). The highest concentration of HEMA was 0.22 mmol/l (Tetric EvoCeram(®) Bulk Fill, methanol, 7 d, PF 15%), the highest concentration of TEGDMA was 0.3 mmol/l (X-tra fil, water, 7 d, PF 15%) and the highest concentration of DMABEE was 0.05 mmol/l (QuiXFil™, water, 7 d, PF 35%).
  
  
  CONCLUSIONS
  PF 15% and PF 35% can lead to reduced and/or increased elution of some bulk-fill components, compared to unbleached bulk-fill composites.
authors.affiliation: Department of Operative/Restorative Dentistry, Periodontology and Pedodontics, Ludwig-Maximilians-University of Munich, Goethestr. 70, 80336 Munich, Germany; Walther-Straub-Institute of Pharmacology and Toxicology, Nussbaumstr. 26, 80336 Munich, Germany.
authors.forename: Lena
authors.initials: L
authors.lastname: Schuster
authors.affiliation: Department of Operative/Restorative Dentistry, Periodontology and Pedodontics, Ludwig-Maximilians-University of Munich, Goethestr. 70, 80336 Munich, Germany; Walther-Straub-Institute of Pharmacology and Toxicology, Nussbaumstr. 26, 80336 Munich, Germany.
authors.forename: Franz-Xaver
authors.initials: FX
authors.lastname: Reichl
authors.affiliation: Department of Operative/Restorative Dentistry, Periodontology and Pedodontics, Ludwig-Maximilians-University of Munich, Goethestr. 70, 80336 Munich, Germany; Walther-Straub-Institute of Pharmacology and Toxicology, Nussbaumstr. 26, 80336 Munich, Germany.
authors.forename: Lena
authors.initials: L
authors.lastname: Rothmund
authors.affiliation: Department of Operative/Restorative Dentistry, Periodontology and Pedodontics, Ludwig-Maximilians-University of Munich, Goethestr. 70, 80336 Munich, Germany; Walther-Straub-Institute of Pharmacology and Toxicology, Nussbaumstr. 26, 80336 Munich, Germany.
authors.forename: Xiuli
authors.initials: X
authors.lastname: He
authors.affiliation: Department of Operative/Restorative Dentistry, Periodontology and Pedodontics, Ludwig-Maximilians-University of Munich, Goethestr. 70, 80336 Munich, Germany; Walther-Straub-Institute of Pharmacology and Toxicology, Nussbaumstr. 26, 80336 Munich, Germany.
authors.forename: Yang
authors.initials: Y
authors.lastname: Yang
authors.affiliation: KU Leuven Biomat, Department of Oral Health Sciences, KU Leuven, Kapucijnenvoer 7, B-3000 Leuven, Belgium.
authors.forename: Kirsten L
authors.initials: KL
authors.lastname: Van Landuyt
authors.affiliation: Bundeswehr Institute of Pharmacology and Toxicology, Neuherbergstr. 11, 80937 Munich, Germany; Walther Straub Institute of Pharmacology and Toxicology, Ludwig Maximilians University of Munich, Goethestraße 33, 80336 Munich, Germany.
authors.forename: Kai
authors.initials: K
authors.lastname: Kehe
authors.affiliation: Department of Operative Dentistry and Periodontology, University Medical Center Freiburg, Dental, School and Hospital, Hugstetterstraße 55, 79106 Freiburg, Germany.
authors.forename: Olga
authors.initials: O
authors.lastname: Polydorou
authors.affiliation: Department of Operative/Restorative Dentistry, Periodontology and Pedodontics, Ludwig-Maximilians-University of Munich, Goethestr. 70, 80336 Munich, Germany.
authors.forename: Reinhard
authors.initials: R
authors.lastname: Hickel
authors.affiliation: Department of Operative/Restorative Dentistry, Periodontology and Pedodontics, Ludwig-Maximilians-University of Munich, Goethestr. 70, 80336 Munich, Germany; Walther-Straub-Institute of Pharmacology and Toxicology, Nussbaumstr. 26, 80336 Munich, Germany. Electronic address: christof.hoegg@lrz.uni-muenchen.de.
authors.forename: Christof
authors.initials: C
authors.lastname: Högg
mesh_terms: D010129:4-Aminobenzoic Acid / Q000737:chemistry; D002849:Chromatography, Gas; D003188:Composite Resins / Q000737:chemistry*; D004338:Drug Combinations; D013058:Mass Spectrometry; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D010545:Peroxides / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000737:chemistry; D011145:Polyvinyls / Q000737:chemistry*; D058205:Tooth Bleaching Agents / Q000737:chemistry*; D014508:Urea / Q000031:analogs & derivatives* / Q000737:chemistry
chemical_list: D003188:Composite Resins; D004338:Drug Combinations; D008689:Methacrylates; D010545:Peroxides; D011109:Polymethacrylic Acids; D011145:Polyvinyls; C510379:QuiXfil; C501891:Tetric EvoCeram; D058205:Tooth Bleaching Agents; C529733:X-tra fil composite resin; C093177:tooth-bleaching agent, Opalescence; C020946:triethylene glycol dimethacrylate; D011092:Polyethylene Glycols; C005044:hydroxyethyl methacrylate; D014508:Urea; C028643:trimethylolpropane trimethacrylate; D010129:4-Aminobenzoic Acid
keywords: Bleaching; Bulk-fill composite; Comonomer; Elution; Peroxide; Polymer network