title: Cytotoxicity evaluation of a copaiba oil-based root canal sealer compared to three commonly used sealers in endodontics.
abstract: BACKGROUND
  The constant development of new root canal sealers has allowed the solution of a large number of clinical cases in endodontics, however, cytotoxicity of such sealers must be tested before their validation as filling materials. The aim of this study was to evaluate the cytotoxic effect of a new Copaiba oil-based root canal sealer (Biosealer [BS]) on osteoblast-like Osteo-1 cells.
  
  
  METHODS
  The experimental groups were formed according to the culture medium conditioned with the tested sealers, as follows: Control group (CG) (culture medium without conditioning); Sealer 26 (S26) - culture medium + S26; Endofill (EF) - culture medium + EF; AH Plus (AHP) - culture medium + AHP; and BS - culture medium + BS (Copaiba oil-based sealer). The conditioned culture medium was placed in contact with 2 × 10(4) cells cultivated on 60 mm diameter Petri dishes for 24 h. Then, hemocytometer count was performed to evaluate cellular viability, using Trypan Blue assay. The normal distribution of data was tested by the Kolmogorov-Smirnov test and the values obtained for cellular viability were statistically analyzed (1-way ANOVA, Tukey's test - P < 0.05), with a significance level of 5%.
  
  
  RESULTS
  S26, EF and AHP presented decreased cellular viability considerably, with statistical significance compared with CG (P < 0.05). BS maintained cellular viability similar to CG (P > 0.05).
  
  
  CONCLUSIONS
  The Copaiba oil-based root canal sealer presented promising results in terms of cytotoxicity which indicated its usefulness as a root canal sealer.
authors: Department of Endodontics, School of Dentistry, Federal University of Amazonas, Manaus, Amazonas, Brazil.
authors: Angela Delfina Bittencourt
authors: AD
authors: Garrido
authors: Department of Dentistry, School of Dentistry, University of São Paulo, Brazil.
authors: Sueli Patricia Harumi Miyagi
authors: SP
authors: de Cara
authors: Department of Dentistry, School of Dentistry, University of São Paulo, Brazil.
authors: Marcia Martins
authors: MM
authors: Marques
authors: Department of Endodontics, School of Dentistry, Federal University of Amazonas, Manaus, Amazonas, Brazil.
authors: Emílio Carlos
authors: EC
authors: Sponchiado
authors: Department of Dental Materials and Prosthodontics, University of São Paulo, Ribeirão Preto, São Paulo, Brazil.
authors: Lucas da Fonseca Roberti
authors: Lda F
authors: Garcia
authors: Department of Restorative Dentistry, Ribeirão Preto School of Dentistry, University of São Paulo, Ribeirão Preto, São Paulo, Brazil.
authors: Manoel Damião
authors: MD
authors: de Sousa-Neto
keywords: Copaiba oil-resin; copaifera genus; cytotoxicity; natural products; root canal sealer