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VOLUME 22 , ISSUE 10 ( October, 2021 ) > List of Articles


Evaluation of Free Available Chlorine of Sodium Hypochlorite When Admixed with 0.2% Chitosan: A Preliminary Study

Prashanth Bytarahosalli Rajachar, Mythreyee S Vidhya, Rupali Karale, Vinay Kumar Govindaraju, Nithin K Shetty

Keywords : Chlorhexidine, Chitosan, Ethylenediaminetetraacetic acid, Free available chlorine, Iodometric titration, Sodium hypochlorite

Citation Information : Rajachar PB, Vidhya MS, Karale R, Govindaraju VK, Shetty NK. Evaluation of Free Available Chlorine of Sodium Hypochlorite When Admixed with 0.2% Chitosan: A Preliminary Study. J Contemp Dent Pract 2021; 22 (10):1171-1174.

DOI: 10.5005/jp-journals-10024-3207

License: CC BY-NC 4.0

Published Online: 07-02-2022

Copyright Statement:  Copyright © 2021; The Author(s).


Aim and objective: The aim of the study was to evaluate the changes in free available chlorine (FAC) when 6% sodium hypochlorite (NaOCl) is admixed with irrigants 17% ethylenediaminetetraacetic acid (EDTA), 2% chlorhexidine (CHX), and 0.2% chitosan in varying proportions of 90:10, 80:20, and 50:50. Materials and methods: The 25 mL aliquots of 6% NaOCl were admixed in varying proportions of 90:10, 80:20, and 50:50 with secondary irrigation solutions: (a) 17% EDTA, (b) 2% CHX, (c) 0.2% chitosan. Iodometric titration was done to evaluate the change in FAC. Statistical analysis used: Kruskal–Wallis and Mann–Whitney tests. Results: On titration, the mean FAC value of NaOCl at baseline was 1.99 g%. On mixing NaOCl with EDTA, the FAC decreased in all the three proportions and the values were 0.17 g%, 0.17 g%, and 0.06 g% at 90:10, 80:20, and 50:50 ratios, respectively. pH obtained was 9.55 at 50:50 ratio. On mixing NaOCl with CHX, FAC reduced and the values were 1.84 g%, 1.72 g%, and 0.27 g% at 90:10, 80:20, and 50:50 ratios, respectively. pH obtained was 10.87 at 50:50 ratio. On mixing NaOCl and chitosan, the FAC remained unaltered in all the three proportions and the values were 1.64 g%, 1.51 g%, and 1.63 g% at 90:10, 80:20, and 50:50 ratios, respectively. pH obtained was 11 at 50:50 ratio. Conclusion: Combination of NaOCl and chitosan did not lead to a reduction in FAC and the pH of the solution remained unaltered, suggesting that tissue-dissolving property of NaOCl might be preserved. Clinical significance: The combination of chitosan with NaOCl is advantageous in two ways. Firstly, FAC remained unaltered and the pH of the solution was also maintained at 11.05 indicating that the tissue-dissolving property of NaOCl prevailed. Secondly, chitosan is known for its chelating property and is effective in smear layer removal. With further in vivo and in vitro studies, a combination of chitosan and NaOCl can be proposed as a novel irrigant.

  1. Gonçalves LS, Rodrigues RC, Junior CV, et al. The effect of sodium hypochlorite and chlorhexidine as irrigant solutions for root canal disinfection: a systematic review of clinical trials. J Endod 2016;42(4):527–532. DOI: 10.1016/j.joen.2015.12.021.
  2. Krishnan U, Saji S, Clarkson R, et al. Free active chlorine in sodium hypochlorite solutions admixed with Octenidine, SmearOFF, Chlorhexidine, and EDTA. J Endod 2017;43(8):1354–1359. DOI: 10.1016/j.joen.2017.03.034.
  3. Zehnder M, Schmidlin P, Sener B, et al. Chelation in root canal therapy reconsidered. J Endod 2005;31(11):817–820. DOI: 10.1097/01.don.0000158233.59316.fe.
  4. Zehnder M. Root canal irrigants. J Endod 2006;32(5):389–398. DOI: 10.1016/j.joen.2005.09.014.
  5. Rossi-Fedele G, Doğramaci EJ, Guastalli AR, et al. Antagonistic Interactions between Sodium Hypochlorite, Chlorhexidine, EDTA, and Citric Acid. J Endod 2012;38(4):426–431. DOI: 10.1016/j.joen.2012.01.006.
  6. Silva PV, Guedes DF, Nakadi FV, et al. Chitosan: a new solution for removal of smear layer after root canal instrumentation. Int Endod J 2013;46(4):332–338. DOI: 10.1111/j.1365-2591.2012.02119.x.
  7. Darrag AM. Effectiveness of different final irrigation solutions on smear layer removal in intraradicular dentin. Tanta Dent J 2014;11(2):93–99. DOI: 10.1016/j.tdj.2014.06.002.
  8. Geethapriya N, Subbiya A, Padmavathy K, et al. Effect of chitosan-ethylenediamine tetraacetic acid on Enterococcus faecalis dentinal biofilm and smear layer removal. J Conserv Dent 2016;19(5):472–477. DOI: 10.4103/0972-0707.190022.
  9. Estrela C, Estrela CRA, Barbin EL, et al. Mechanism of action of Sodium hypochlorite. Braz Dent J 2002;13(2):113–117. DOI: 10.1590/s0103-64402002000200007.
  10. Mohammadi Z. Sodium hypochlorite in endodontics: an update review. Int Dent J 2008;58(6):329–341. DOI: 10.1111/j.1875-595x.2008.tb00354.x.
  11. Kandaswamy D, Venkateshbabu N. Root canal irrigants. J Conserv Dent 2010;13(4):256–264. DOI: 10.4103/0972-0707.73378.
  12. Clarkson RM, Podlich HM, Moule AJ. Influence of ethylenediaminetetraacetic acid on the active chlorine content of sodium hypochlorite solutions when mixed in various proportions. J Endod 2011;37(4):538–543. DOI: 10.1016/j.joen.2011.01.018.
  13. Orhan EO, Irmak Ö, Hür D, et al. Does Para-chloroaniline really form after mixing sodium hypochlorite and chlorhexidine? J Endod 2016;42(3):455–459. DOI: 10.1016/j.joen.2015.12.024.
  14. Wright PP, Kahler B, Walsh LJ. Alkaline sodium hypochlorite irrigant and its chemical interactions. Materials (Basel) 2017;10(10):1147. DOI: 10.3390/ma10101147.
  15. Del Carpio-Perochena A, Bramante CM, Duarte MA, et al. Chelating and antibacterial properties of chitosan nanoparticles on dentin. Restor Dent Endod 2015;40(3):195–201. DOI: 10.5395/rde.2015.40.3.195.
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