Scientific Online Resource System

Izvestia Journal of the Union of Scientists - Varna. Medicine and Ecology Series

Methods for increasing the efficiency of NaOCl

Denitsa Zaneva-Hristova, Boris Valkov, Tsvetelina Borisova-Papancheva


Sodium hypochlorite has a strong antibacterial effect and the ability to dissolve organic substances. It cannot remove the smear layer formed on the walls of the canal after mechanical preparation. The main disadvantages of this irrigant are its cytotoxicity, unpleasant smell and taste, and the ability to cause corrosion on metallic objects. The free chlorine in NaOCl dissolves the necrotic tissue by digesting the proteins in amino acids.

It is available in gel, liquid, and surfactant modified form.

The applicable concentrations range from 0.5% to 5.25%. Reducing the concentration of the solution lowers the level of its toxicity, antibacterial effect and ability to dissolve tissues. Increasing its volume or temperature increases its effectiveness.


irrigant, sodium hypochlorite, microorganisms, E. faecalis, ultrasonic irrigation

Full Text


Norhayati Luddin and Hany Mohamed Aly Ahmed, The antibacterial activity of sodium hypochlorite and chlorhexidine against Enterococcus faecalis: A review on agar diffusion and direct contact methods, J Conserv Dent. 2013 Jan-Feb; 16(1): 9–16.

Zahed Mohammadi, Sodium hypochlorite in endodontics: an update review, Int Dent J, 2008 Dec;58(6):329-41

Mathew ST (2015) Sodium Hypochlorite Dental Emergency-A Review. Int J Dent Oral Health 1(4)

Zahed Mohammadi, Sodium hypochlorite in endodontics: an update review, International Dental Journal (2008) 58, 329-341

Mohammadi Z, Mombeinipour A, Giardino L, Shahriari S, Residual antibacterial activity of a new modified sodium hypochlorite-based endodontic irrigation solution.Medicina Oral, Patologı´a Oral y Cirugı´a Bucal 16, e588–92

Robin J Slaughter , Martin Watts, J Allister Vale, Jacob R Grieve, Leo J Schep ,The clinical toxicology of sodium hypochlorite, Clin Toxicol (Phila),2019 May;57(5):303-311

Dina Al-Sudani, Husein A. Al Omar, Evaluation of Sodium Hypochlorite (NaOCl) Gel as an Endodontic Irrigant, Journal of Biomaterials and Tissue Engineering1(2):215-218

Vahid Zand, Mehrdad Lotfi, Mohammad Hosein Soroush, Amir Ardalan Abdollahi, Mehdi Sadeghi and Ali Mojadadia, Antibacterial Efficacy of Different Concentrations of Sodium Hypochlorite Gel and Solution on Enterococcus faecalis Biofilm,Iranian Endodontic Journal, Vol. 11 No. 4 (2016), Page 315-319

Mohamed El Sayed, Nikta Ghanerad, Fatemeh Rahimi, Mahin Shabanpoor and Zeinab Shabanpour, Antibacterial Activity of Sodium Hypochlorite Gel versus Different Types of Root Canal Medicaments Using Agar Diffusion Test: An In Vitro Comparative Study, Int J Dent. 2020 Nov 28;2020:6483026

Palazzi F, Morra M, Mohammadi Z, Grandini S, Giardino L. Surface tension comparison of 5.25% sodium hypochlorite solution with three new sodium hypochlorite-based endodontic irrigants. Int Endod J 2012;45:129-135

Luciano Giardino, Carlos Estrela, Zahed Mohammadi, Flavio Palazzi, Antibacterial Power of Sodium Hypochlorite Combined with Surfactants and Acetic Acid, Brazilian Dental Journal (2014) 25(4): 289-294

V B Berber , B P F A Gomes, N T Sena, M E Vianna, C C R Ferraz, A A Zaia, F J Souza-Filho, Efficacy of various concentrations of NaOCl and instrumentation techniques in reducing Enterococcus faecalis within root canals and dentinal tubules, Int Endod J, 2006 Jan;39(1):10-7

Venkatachalam Prakash, Balashankar Ajay Sathya, Ramachandran Tamilselvi,Arunajatesan Subbiya, SODIUM HYPOCHLORITE IN ENDODONTICS – THE BENCH MARK IRRIGANT: A REVIEW, European Journal of Molecular & Clinical Medicine ISSN 2515-8260 Volume 07, Issue 5, 2020

Mohammad Forough Reyhani, Yousef Rezagholizadeh, Mohammad Reza Narimani, Lotfollah Rezagholizadeh, Mohammad Mazani, Mohammad Hossein Soroush Barhaghi and Yavar Mahmoodzadeh, Antibacterial effect of different concentrations of sodium hypochlorite on Enterococcus faecalis biofilms in root canals, J Dent Res Dent Clin Dent Prospects. 2017 Autumn; 11(4): 215–221

E S Senia, F J Marshall, S Rosen, The solvent action of sodium hypochlorite on pulp tissue of extracted teeth, Oral Surg Oral Med Oral Pathol, 1971 Jan;31(1):96-103

Ghassan Yared, Ghada Al Asmar Ramli,Antibacterial Ability of Sodium Hypochlorite Heated in the Canals of Infected Teeth: An Ex Vivo Study, Cureus, 2020 Feb 13;12(2):e6975

Aldo del Carpio-Perochena, Clovis Monteiro Bramante, Marco Hungaro Duarte, Flaviana Bombarda de Andrade, Marcia Zardin Graeff, Marina Marciano da Silva, Bruno Cavalini Cavenago and Samuel Lucas Fernandes, Effect of Temperature, Concentration and Contact Time of Sodium Hypochlorite on the Treatment and Revitalization of Oral Biofilms, J Dent Res Dent Clin Dent Prospect,2015 Fall;9(4):209-15

Alfredo Iandolo, Massimo Amato, Alberto Dagna, Claudio Poggio, Dina Abdellatif, Vittorio Franco, Giuseppe Pantaleo Intracanal heating of sodium hypochlorite: Scanning electron microscope evaluation of root canal walls, Journal of conservative dentistry, Volume 21, Issue 5, Page : 569-573, 2018

George Sirtes , Tuomas Waltimo, Marc Schaetzle, Matthias Zehnder, The effects of temperature on sodium hypochlorite short-term stability, pulp dissolution capacity, and antimicrobial efficacy, J. Endod, 2005 Sep;31(9):669-71

S S Virdee, D J J Farnell, M A Silva, J Camilleri, P R Cooper, P L Tomson, The influence of irrigant activation, concentration and contact time on sodium hypochlorite penetration into root dentine: an ex vivo experiment,Int Endod J, 2020 Jul;53(7):986-997



Font Size