title: Effect of water storage and heat treatment on the cytotoxicity of soft liners.
abstract: OBJECTIVE
  To evaluate the effect of water storage time on the cytotoxicity of soft liners.
  
  
  METHODS
  Sample discs of soft liners Dentusoft, Dentuflex, Trusoft, Ufi-Gel-P and denture base acrylic resin Lucitone-550 were prepared and divided into four groups: GN: No treatment, G24: Stored in water at 37°C for 24 h; G48: Stored in water at 37°C for 48 h, GHW: Immersed in water at 55°C for 10 min. To analyse the cytotoxic effect, three samples of each group were placed in tubes with Dubelcco's Modified Eagle Mediums and incubated at 37°C for 24 h. During this period, the toxic substances were leached to the culture medium. The cytotoxicity was analysed quantitatively by the incorporation of radioactivity (3)H-thymidine checking the number of viable cells (synthesis of DNA). The data were statistically analysed using two-way anova and Tukey's honestly significant difference tests (α = 0.05).
  
  
  RESULTS
  Treatments did not reduce the cytotoxicity effect of the soft liners (p > 0.05). It was found that Ufi-Gel-P had a non-cytotoxic effect, Trusoft had a slightly cytotoxic effect, Dentuflex had a moderated cytotoxic effect, Dentusoft alternated between slightly and non-cytotoxic effect, and Lucitone-550 had non-cytotoxic effect when stored in water for 48 h.
  
  
  CONCLUSIONS
  The effect of water storage and the heat treatment did not reduce the cytotoxicity of the soft liners.
authors.affiliation: Department of Dentistry, Ponta Grossa State University, Ponta Grossa, Parana, Brazil.
authors.forename: Lidia Yileng
authors.initials: LY
authors.lastname: Tay
authors.forename: Daniel Rodrigo
authors.initials: DR
authors.lastname: Herrera
authors.forename: Cristiane Campos Costa
authors.initials: CC
authors.lastname: Quishida
authors.forename: Iracilda Zeppone
authors.initials: IZ
authors.lastname: Carlos
authors.forename: Janaina Habib
authors.initials: JH
authors.lastname: Jorge
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry / Q000633:toxicity; D000818:Animals; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D017077:Culture Media, Conditioned; D003764:Dental Materials / Q000737:chemistry / Q000633:toxicity*; D003822:Denture Liners; D004129:Dimethylpolysiloxanes / Q000737:chemistry / Q000633:toxicity; D005347:Fibroblasts / Q000187:drug effects; D006358:Hot Temperature; D008422:Materials Testing; D008768:Methylmethacrylates / Q000737:chemistry / Q000633:toxicity; D051379:Mice; D019275:Radiopharmaceuticals; D012826:Silicone Elastomers / Q000737:chemistry / Q000633:toxicity; D013696:Temperature; D013936:Thymidine; D013997:Time Factors; D014316:Tritium; D014867:Water
chemical_list: D000180:Acrylic Resins; D017077:Culture Media, Conditioned; D003764:Dental Materials; D004129:Dimethylpolysiloxanes; D008768:Methylmethacrylates; D019275:Radiopharmaceuticals; D012826:Silicone Elastomers; C483158:Ufi gel; D014867:Water; D014316:Tritium; C040291:Lucitone; C013830:baysilon; C009931:poly(ethylmethacrylate); D013936:Thymidine