title: Contemporary methacrylate resin-based root canal sealers exhibit different degrees of ex vivo cytotoxicity when cured in their self-cured mode.
abstract: The cytotoxicity of four methacrylate resin-based sealers was investigated by the 3-(4,5-dimethyl-thiazoyl)-2,5-diphenyl-tetrazolium bromide assay, which measures cell viability by assessing its succinate dehydrogenase activity. The sealers were polymerized in the self-cured mode to simulate the setting condition upon their extrusion into periradicular tissues. Disks were prepared from EndoREZ (Ultradent, South Jordan, UT), RealSeal (SybronEndo, Orange, CA), MetaSEAL (Parkell, Farmington, NY), and RealSeal SE (SybronEndo) together with positive and negative controls. After setting, they were placed in direct contact with rat osteosarcoma (ROS 17/2.8) cells and for 5 succeeding weeks after immersing in simulated body fluid (SBF). All sealers exhibited severe toxicity initially (week 0). EndoREZ and RealSeal remained severely toxic after five cycles of SBF immersion. Toxicity of the two self-etching resin-based sealers MetaSEAL and RealSeal SE decreased gradually over time. Transmission electron microscopy of cells exposed to RealSeal SE showed variable degrees of cell injury that reflect its toxicity status. Cells with intact mitochondria were identifiable after the sealer became noncytotoxic at week 5.
authors.affiliation: Department of Endodontics, School of Dentistry, Medical College of Georgia, Augusta, GA 30912-1129, USA.
authors.forename: Jason M
authors.initials: JM
authors.lastname: Ames
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Loushine
authors.forename: Brian R
authors.initials: BR
authors.lastname: Babb
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Bryan
authors.forename: Petra E
authors.initials: PE
authors.lastname: Lockwood
authors.forename: Mai
authors.initials: M
authors.lastname: Sui
authors.forename: Steven
authors.initials: S
authors.lastname: Roberts
authors.forename: R Norman
authors.initials: RN
authors.lastname: Weller
authors.forename: David H
authors.initials: DH
authors.lastname: Pashley
authors.forename: Franklin R
authors.initials: FR
authors.lastname: Tay
mesh_terms: D000180:Acrylic Resins / Q000633:toxicity*; D000818:Animals; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D003188:Composite Resins / Q000633:toxicity; D008422:Materials Testing; D008689:Methacrylates / Q000633:toxicity; D046529:Microscopy, Electron, Transmission; D010006:Osteoblasts / Q000187:drug effects*; D051381:Rats; D012387:Root Canal Filling Materials / Q000633:toxicity*; D055116:Self-Curing of Dental Resins
chemical_list: D000180:Acrylic Resins; D003188:Composite Resins; C481259:EndoRez; D008689:Methacrylates; C511498:Real Seal composite resin; D012387:Root Canal Filling Materials; C534239:metaseal