title: Cytotoxicity testing of methyl and ethyl 2-cyanoacrylate using direct contact assay on osteoblast cell cultures.
abstract: OBJECTIVE
  Cyanoacrylate has been used as a commercial tissue adhesive. Recently, ethyl 2-cyanoacrylate has been suggested for the fixation of onlay autogenous bone graft. However, ethyl 2-cyanoacrylate must be biocompatible with bone tissue. This study evaluated the cytotoxicity of cyanoacrylate adhesives using a direct contact assay on human oral osteoblast cells.
  
  
  METHODS
  Osteoblastic cells derived from human alveolar bone of the mandible were cultured with or without cyanoacrylate. The CA1 group contained methyl 2-cyanoacrylate, the CA2 group contained ethyl 2-cyanoacrylate, and the CA3 group did not contain cyanoacrylate (control). This study investigated cell morphology, which included the inhibition zone, and cytotoxicity was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, which was measured as optical density. Data from the MTT assay were tested statistically using SigmaStat 3.5.
  
  
  RESULTS
  Dead cells found around the CA1- and CA2-treated cells constituted inhibitory zones that varied from 200 to 500 μm. There was no inhibitory zone in the CA3 group. Cell viability evaluated by the MTT assay showed that the CA2 and CA3 optical densities were not significantly different. The CA1 optical densities differed significantly from the CA3 optical densities.
  
  
  CONCLUSIONS
  Within the limits of this study, the MTT method supported the conclusion that ethyl 2-cyanoacrylate is biocompatible according to a direct contact assay on human osteoblast cell cultures and suggests its usefulness in bone graft fixation.
authors.affiliation: Department of Morphology, Ribeirão Preto Dental School, São Paulo University, Ribeirão Preto, São Paulo, Brazil. wmmelo@usp.br
authors.forename: Willian Morais
authors.initials: WM
authors.lastname: De Melo
authors.forename: William Marcatti Amarú
authors.initials: WM
authors.lastname: Maximiano
authors.forename: Antônio Azoubel
authors.initials: AA
authors.lastname: Antunes
authors.forename: Marcio Mateus
authors.initials: MM
authors.lastname: Beloti
authors.forename: Adalberto Luiz
authors.initials: AL
authors.lastname: Rosa
authors.forename: Paulo Tambasco
authors.initials: PT
authors.lastname: de Oliveira
mesh_terms: D000539:Alveolar Process / Q000166:cytology / Q000187:drug effects; D002478:Cells, Cultured; D003487:Cyanoacrylates / Q000633:toxicity*; D006801:Humans; D010006:Osteoblasts / Q000187:drug effects*; D014014:Tissue Adhesives / Q000633:toxicity*
chemical_list: D003487:Cyanoacrylates; D014014:Tissue Adhesives; C029054:ethyl 2-cyanoacrylate; C008424:methyl 2-cyanoacrylate