title: In vitro Analysis of Cytotoxicity of Temporary Resilient Relining Materials.
abstract: OBJECTIVE
  The aim of this study is to evaluate the in vitro response of human gingival fibroblasts in primary cultures to two materials for temporary relining of dentures: Temporary Soft (TDV, Brazil) and Trusoft (Bosworth, USA) for 24 hours, 7 and 30 days by using a multi-parametric analysis.
  
  
  METHODS
  Each material sample (TDV, TS, Polystyrene, Latex) was prepared and incubated in a culture medium for 1, 7, and 30 days at 37°C. Human gingival fibroblasts were exposed to the extracts and cell viability was evaluated by a multi-parametric assay, which allowed sequential analysis of mitochondrial activity (XTT), membrane integrity [neutral red (NR)], and cell density [crystal violet dye exclusion (CVDE)] in the same cells. Analysis of variance (ANOVA) was used to test the interactions of the three sources of variation (material, test method, and time) with the proportions of viable cells for each relining material.
  
  
  RESULTS
  Both evaluated materials (TDV and TS) had low cytotoxic effects during 1, 7, and 30 days after manipulation of the material, as assessed by all three methods used. A statistical difference was found when comparing the negative control group (latex fragments) with the other groups, which showed high toxicity and low percentage of cell viability in all tests used. There was no significant difference among other materials (p > 0.05).
  
  
  CONCLUSIONS
  Low cytotoxicity levels were detected by representatives of the major groups of temporary prosthetic relining materials, as evaluated by multiple cellular viability parameters in human fibroblasts.
  
  
  CONCLUSIONS
  There are various soft materials on the market for relining prostheses; however, the effects of these materials on tissues need to be clarified to avoid problems for patients.
authors.affiliation: Department of Clinical Dentistry, Federal Fluminense University, Niteroi, Rio de Janeiro, Brazil.
authors.forename: Isleine P
authors.initials: IP
authors.lastname: Caldas
authors.affiliation: Professor, Department of Geriatric Dentistry, Federal Fluminense University, Niteroi, Rio de Janeiro, Brazil, Phone: +5502126299835, e-mail: scelza@terra.com.br.
authors.forename: Miriam Z
authors.initials: MZ
authors.lastname: Scelza
authors.affiliation: Department of Clinical Dentistry, Federal Fluminense University, Niteroi, Rio de Janeiro, Brazil.
authors.forename: Marco A
authors.initials: MA
authors.lastname: Gallito
authors.affiliation: Department of Molecular and Cell Biology, Federal Fluminense University, Niteroi, Rio de Janeiro, Brazil.
authors.forename: Gutemberg
authors.initials: G
authors.lastname: Alves
authors.affiliation: Department of Statistics, Federal Fluminense University Niteroi, Rio de Janeiro, Brazil.
authors.forename: Licínio
authors.initials: L
authors.lastname: Silva
mesh_terms: D001938:Brazil; D016923:Cell Death; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D003822:Denture Liners; D005347:Fibroblasts / Q000187:drug effects*; D005840:Gentian Violet; D005881:Gingiva / Q000166:cytology; D006801:Humans; D066298:In Vitro Techniques; D008422:Materials Testing; D009499:Neutral Red; D013194:Staining and Labeling; D018675:Toxicity Tests
chemical_list: D009499:Neutral Red; D005840:Gentian Violet
keywords: Biocompatibility; Cytotoxicity; Dental prosthesis; Denture liners; Fibroblasts; Laboratory research.