title: Comparative cytotoxicity of five current dentin bonding agents: role of cell cycle deregulation.
abstract: To compare the cytotoxicity of three nano-dentin bonding agents (nano-DBAs) and two non-nano-DBAs using Chinese hamster ovary (CHO-K1) cells. We found that nano fillers were not the major contributing factor in DBA cytotoxicity, as analyzed by colony forming assay and 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay. Exposure of CHO-K1 cells to all three tested total-etching DBAs led to G(0)/G(1) cell cycle arrest, whereas exposure to higher concentrations of two tested nano-DBAs induced G(2)/M arrest. All five DBAs further induced apoptosis at the highest concentration, as analyzed by propidium iodide staining flow cytometry. The toxicity of all DBAs (1:4000v/v or higher) is related to increased reactive oxygen species (ROS) production, as analyzed by single cell DCF fluorescence flow cytometry. These results indicate that clinical application of DBAs may be potentially toxic to dental pulp tissues. Cytotoxicity of DBAs is associated with ROS production, cell cycle deregulation and apoptosis. Presence of methacrylate monomers such as PENTA and UDMA is possibly the major cytotoxic factor for DBAs. Further studies on other toxicological endpoints of nano-DBAs are necessary to highlight their safe use.
authors.affiliation: Laboratory of Pharmacology and Toxicology, Department of Dentistry & School of Dentistry, National Taiwan University Hospital and National Taiwan University Medical College, Taipei, Taiwan.
authors.forename: Hung-Wei
authors.initials: HW
authors.lastname: Yeh
authors.forename: Mei-Chi
authors.initials: MC
authors.lastname: Chang
authors.forename: Chun-Pin
authors.initials: CP
authors.lastname: Lin
authors.forename: Wan-Yu
authors.initials: WY
authors.lastname: Tseng
authors.forename: Hsiao-Hua
authors.initials: HH
authors.lastname: Chang
authors.forename: Tong-Mei
authors.initials: TM
authors.lastname: Wang
authors.forename: Yi-Jane
authors.initials: YJ
authors.lastname: Chen
authors.forename: Chiu-Chun
authors.initials: CC
authors.lastname: Lin
authors.forename: Ting-Ting
authors.initials: TT
authors.lastname: Yang
authors.forename: Li-Deh
authors.initials: LD
authors.lastname: Lin
authors.forename: Jiiang-Huei
authors.initials: JH
authors.lastname: Jeng
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D016466:CHO Cells / Q000166:cytology / Q000187:drug effects / Q000502:physiology; D002453:Cell Cycle / Q000187:drug effects*; D006224:Cricetinae; D003412:Cricetulus; D017220:Dentin-Bonding Agents / Q000633:toxicity*; D006801:Humans; D008422:Materials Testing; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D017220:Dentin-Bonding Agents; D017382:Reactive Oxygen Species