Have you ever wondered what sodium hypochlorite really does? Sodium hypochlorite is responsible for tissue dissolution. In essence, it dissolves all the pulpal tissue as part of the chemical disinfection during your root canal.
I love it when I pull out the pulp in one big piece because I do a little science experiment to teach my assistants the importance of sodium hypochlorite with respect to time. So, the last time this happened I decided to take some pictures. This is from the palatal root.
So, I put it in a cup…
And soaked it with some sodium hypochlorite and waited. After about 10 minutes, this is what it looked like…
So, you can see that the tissue is still there, it’s a different color, but it isn’t quite gone yet. So, I waited another 5 minutes.
The tissue is still kind of there, but you can see that it’s starting to get eaten through a bit. So, I let it sit a little longer…
and now only a little speck left, so I gave it another 5 minutes, and abracadabra, it was all gone!!
So 25 minutes in total and there was no longer anything left in the cup, just from letting it soak, and without doing anything else.
So, the moral of the story is don’t rush your root canals — your hypochlorite needs time to do its job! This is more of a tortoise task than a rabbit one.
And if you need more time for it to work on your patient, go do a hygiene check and let your hypochlorite hang out for some more time. It works! Plus that’s a win-win for your patient. And it’s a teaching tool for your team!
Thank you Maira – so glad you’re reading!
Great mam. Can you repeat the experiment with some form of activation like PUI or sonic? It would be good to know their effect too.
Really helpful tip…I’m gonna follow this protocol from now
Trust me – it works!
That is a great job but I have a question.
What is the concentrate of the sodium hypo chloride that you use it in the cup.
The concentration is 5.25%. Hope this helps.
I took an end hands-on course a few years ago with Dr. Steve Buchanan and he recommended always leaving hypochlorite in the canal for a minimum of 30 minutes for this very reason. Looks like he was correct!
You got it Richard! Talk soon-
Itz great! From now on, wud definitely give more time to this super disinfectant to work it wonders.. Thank you Ma’am for this useful tip..
Thank you so much for reading!
Good demonstration. Hedaya
Thanks for following Hedaya!
Hi Dr. Sonia
can we leave sodium hypochlorite as the last irrigant before giving temporary restoration?
Yup, that’s my preference.
Will it cause any problems to periapical tissue, if we use it as last irrigant
Hey there!! I always use sodium hypochlorite as my last irrigant. So you are all good!!
So that means, we won’t place the calcium hydroxide then. Is that right?
Atif, calcium hydroxide works synergistically with sodium hypochlorite. So sometimes you still need both! If this helps you remember, calcium hydroxide is like a meat tenderizer, and it helps the hypo’s mechanism of action. Hope that helps!
Sonia, do you as a general rule use multiple NaOCl incubation periods when disinfecting root canals? Are you able to reduce those times with an EndoActivator?
BTW, thank you so much for your clinical tips and your site as a whole. Super informative and a genuinely amazing resource for Endo.
I like to use as much volume of irrigant as I can and yes, I do give it a lot of time, replenishing it often. I don’t believe in 30 minute endo, that just doesn’t give the hypo enough time to work. I don’t think that the EndoActivator reduces the time, instead it helps push it in hard to reach areas. Hope this helps.
This is really helpful. I would just like to know the type of syringe u r using to deposit the hypochorite solution. What shoud be the ideal one so that it remains inside the root for a while. Please can u post a picture of the syringe??
Hey there. I use the 30 gauge Maxi-probe irrigating needles. You can check out my top 10 tools blog https://soniachopradds.com/blog/top-10-endodontic-tools-root-canals/
Thanks Sonia , Very informative .
should we have to dilute Sod. Hypo ? and what is the ideal concentration for NaOCL ?
Please don’t dilute your bleach. The studied concentration is 5.25% to 6%.
Hi Sonia, nice experiment to show what sodium hypochlorite does…. this again shows that it’s really important to take time for your rootcanaltreatment…….
Quality takes time, right?
Thanks for the tip. Can we use Naocl as our last irrigant before obturation ?
Could you please tell the sequence of irrigants to be used in vital and non vital endo tx.
I use hypo last, just before my obturation. But, I will also do a quick rinse with EDTA prior to that. Hope that helps.
May I know what concentration of Hypo was used for this experiment? And what is the most ideally recommended concentration for rcts?
5.25% was used and 5.25% to 6% is what has been studied in the classic literature.
You’ve always inspired me to practice a better Dentistry ma’am. Keep sharing your knowledge and continue to inspire more clinicians like me.
Thank you so much for reading!
With long-standing septic canals, the pulp is often already digested by bacteria; the challenge is killing the bacteria and its spores rather than dissolving it. In those cases, HOCl- is more relevant as an irrigating agent than NaOCl and the use of Calcium hydroxide becomes especially important in such cases.
Thank you for your comment.
What is your proper technique for allowing it to soak for 30 mins? Would you dispense a small amount of irrigant in the chamber without suction close by or keep suction close?
And during the 30 mins would you put a cotton pellet inside?
When is the irrigant placed, would it b e after the final shaping file and right before obturation?
I irrigate throughout the procedure and then do a big final flush at the the end. Good irrigation is a function of time and also new replenishment of the irrigant. So, it’s a mix of rinsing and soaking. I hope that this helps.