title: [Comparison of cytotoxicity between chemical retraction agents on human gingival fibroblasts in vitro].
abstract: OBJECTIVE
  To choose the best retraction agent for the clinic by evaluating cytotoxic effects of six chemical retraction agents on human gingival fibroblasts (HGF) in vitro.
  
  
  METHODS
  HGF were treated with six chemical retraction agents which included 20% Al2(SO4)3, 5% Al2(SO4)3, 15.5% Fe2(SO4)3, 13.3% Fe2(SO4)3, 0.1% HCl-epinephrine and 0.01% HCl-epinephrine. The damage of direct contact and proliferation inhibit were observed by methyl thiazolyl tetrazolium (MTT) colorimetric assay, the ultra structure was observed under transmission electron microscope (TEM).
  
  
  RESULTS
  All of chemical retraction agents caused cell damage and proliferation inhibit. The ability of cytotoxic effect increased in an order of 0.01% HCl-epinephrine<0.1% HCl-epinephrine<5% Al2(SO4)3<20% Al2(SO4)3<Fe2(SO4)3. There was no statistically significant difference between 13.3% Fe2(SO4)3 group and 15.5% Fe2(SO4)3 group. At HCl-epinephrine group and 5% Al2(SO4)3 group, the number of organelles were decreased, mitochondria and endoplasmic reticulum were swollen. At 20% Al2(SO4)3 group, organelles swelling and decreased number of organelles became more severe, the nuclear chromatin was unevenly distributed. Cell degeneration could be made by Fe2(SO4)3.
  
  
  CONCLUSIONS
  0.01% HCl-epinephrine was the least toxic gingival retraction agents, 13.3% Fe2(SO4)3 and 15.5% Fe2(SO4)3 are found to have the strongest cytotoxic effect on cell cultures.
authors.affiliation: College of Stomatology, Binzhou Medical University, Binzhon 256603, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Liu
authors.forename: Xiao-Ming
authors.initials: XM
authors.lastname: Zhang
authors.forename: Peng-Jie
authors.initials: PJ
authors.lastname: Hao
authors.forename: Min
authors.initials: M
authors.lastname: Hui
authors.forename: Huan-Ying
authors.initials: HY
authors.lastname: Yu
mesh_terms: D000818:Animals; D004837:Epinephrine; D005347:Fibroblasts; D005881:Gingiva; D006801:Humans; D066298:In Vitro Techniques
chemical_list: D004837:Epinephrine