title: Long-term release of monomers from modern dental-composite materials.
abstract: The elution of monomers from composite materials influences the biocompatibility of dental restorations. The purpose of the present study was to investigate the elution of monomers [bisphenol A glycidyl methacrylate (BisGMA), triethylene glycol dimethacrylate (TEGDMA), urethane dimethacrylate (UDMA), and bisphenol A (BPA)] from two light-cured materials (nanohybrid and ormocer) and from a chemically cured composite material, after different curing times (0, 20, 40 and 80 s) and different storage periods (24 h, 7 d, 28 d, and 1 yr after curing). Each specimen was stored in 1 ml of 75% ethanol. This medium was renewed after 24 h, 7 d, 28 d, and 1 yr. The ethanol samples were analyzed using liquid chromatography tandem mass spectrometry (LC-MS/MS). The amount of monomers released from the nanohybrid and the chemically cured composite was significantly higher than released from the ormocer. The curing time exerted a significant effect on the release of monomers. For the nanohybrid, less monomer was released after increasing the curing time. For the ormocer, 80 s of curing resulted in a higher degree of monomer release. The effect of storage differed between the monomers. Although the elution of TEGDMA was significantly decreased after storage for 28 d and 1 yr, a similar amount of BisGMA was released at each storage time-point analyzed, even after 1 yr. The present study showed that ormocer released a very small amount of monomers compared with the other materials.
authors.affiliation: Department of Operative Dentistry and Periodontology, Dental School and Hospital, University Medical Center Freiburg, Freiburg, Germany. olga.polydorou@uniklinik-freiburg.de
authors.forename: Olga
authors.initials: O
authors.lastname: Polydorou
authors.forename: Armin
authors.initials: A
authors.lastname: König
authors.forename: Elmar
authors.initials: E
authors.lastname: Hellwig
authors.forename: Klaus
authors.initials: K
authors.lastname: Kümmerer
mesh_terms: D001559:Benzhydryl Compounds; D001672:Biocompatible Materials / Q000737:chemistry*; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry*; D001840:Dental Bonding / Q000379:methods; D003793:Dental Restoration, Permanent; D008689:Methacrylates / Q000737:chemistry*; D010636:Phenols / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000737:chemistry; D011140:Polyurethanes / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry*; D012995:Solubility; D013997:Time Factors; D000098826:Bisphenol A Compounds
chemical_list: D001559:Benzhydryl Compounds; D001672:Biocompatible Materials; D017438:Bisphenol A-Glycidyl Methacrylate; D003188:Composite Resins; D008689:Methacrylates; D010636:Phenols; D011092:Polyethylene Glycols; D011109:Polymethacrylic Acids; D011140:Polyurethanes; D019279:Resin Cements; C520091:CeramX; C469237:Clearfil Core; C029824:urethane dimethacrylate luting resin; C020946:triethylene glycol dimethacrylate; C006780:bisphenol A; D000098826:Bisphenol A Compounds