Effect of chemical and natural irrigant solutions on microhardness of root dentin– an in vitro study

  • Caren Taffarel
  • Fernanda Duda Bonatto
  • Filipe do Carmo Bonfante
  • Huriel Scartazzini Palhano
  • Cristina de Mattos Pimenta Vidal
  • Doglas Cecchin
  • Matheus Albino Souza


Aim: Modifications in the mechanical properties of dentin may reduce the fracture resistance of tooth, especially after endodontic treatment. The aim of present study was to evaluate the effect of the irrigation with different root canal irrigants on the microhardness of root dentin. Methods: The coronal portion of 60 single-rooted bovine incisors was sectioned and the pulpal tissue removed using endodontic K-files. The roots were cut transversely to obtain 2 fragments, which were embedded in acrylic resin and randomly distributed into six groups (n=20) according to the irrigation protocol: distilled water (DW) (control); 2% chlorhexidine solution (CHX); 6% sodium hypochlorite (NaOCl); 6% calcium hypochlorite (Ca[OCl]2); QMix; and 6.5% grape seed extract solution (GSE). The solutions were kept in contact with the root dentin specimens for 30 min. After that, irrigation with 5 mL of DW was performed. The Vickers microhardness was determined by performing three indentations in all specimens, using 300-g load and 20-second dwell time. The first indentation was made 1.000 μm from the root canal entrance, and two other indentations were made at a distance of 200 μm from each other. The microhardness value for each specimen was obtained as the average of the results for the three indentations. Data were statistically analyzed using oneway ANOVA with 5% significance level. Results: All the tested irrigant solutions maintained the same microhardness level of the root dentin when compared to the control group, with no statistically significant differences between them (p<0.05) Conclusion: The tested irrigant solutions did not present ability to modify the microhardness of root dentin.


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How to Cite
TAFFAREL, Caren et al. Effect of chemical and natural irrigant solutions on microhardness of root dentin– an in vitro study. Brazilian Journal of Oral Sciences, [S.l.], p. e18409, jan. 2019. ISSN 1677-3225. Available at: <https://www.fop.unicamp.br/bjos/index.php/bjos/article/view/1508>. Date accessed: 21 july 2019. doi: https://doi.org/10.20396/bjos.v17i0.8654060.
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