[ Periodontal ]
[ Prosthodontics ]
[ Orthodontics ]
[ Oral/Maxillofacial Surgery ]
[ Oral/Maxillofacial Pathology ]
[ Orofacial Pain / TMJ ]
[ Community Dentistry ]
NaOCL usage
From: Bruce Finnigan
To: ROOTS
Sent: Wednesday, June 13, 2007 9:19 PM
Subject: [roots] NaOCL Usage
Is it common to leave NaOCL in the canal for 15 minutes during the irrigation/disinfection procedure?
Thanks, Bruce
Yes in theory its placed in the canal and flushed during the entire instrumentation phase so can be in their
longer then 15 minutes. but the actual amount in their is small as once the file goes in it displaces most of
the NaOCL coronally - Gregory Kurtzman
Bruce, 15 minutes....your kidding right?
NaOCl doesn't do much in 15 minutes...and you have to constantly replenish and work it around. Why do you
ask? Robin McGrath did a study showing the 30 minute soak, once popularized by some endo lecturers really
doesn't do much - Joey D
I can't instrument many canals in less time than that, so I guess yes. Mine are typically in bleach for over an
hour, but that's how long it takes to get them shaped - Bill
Do you mean without changing the NaOCL from time to
time or leave it "untouched" for this time periode? - chris
I have naocl in the canal from start to finish, obviously changed out a multitude of times, especially now that I’m
playing with the endovac. Are you talking one batch continuously? That would not be nearly as advantageous as fresh
solution circulated through the system. I keep the chamber flooded.- Gary
Only if you want to waste time ;-)) - Fred
J Endod. 2005 May;31(5):359-63.
Reduction of intracanal bacteria using GT rotary instrumentation, 5.25% NaOCl, EDTA, and Ca(OH)2.
McGurkin-Smith R, Trope M, Caplan D , Sigurdsson A .
Department of Endodontics, The University of North Carolina, Chapel Hill, NC 27599, USA.
This study was conducted to determine the bacterial reduction using Profile GT files and a strict irrigation protocol
utilizing 5.25% NaOCl and EDTA. The additive antibacterial effect of Ca(OH)2 was also evaluated. In addition, the
study compared the bacterial reduction with the GT protocol versus larger instrumentation. Thirty-one subjects with
apical periodontitis were recruited. Bacterial samples were taken upon access (S1), after instrumentation and a
strict irrigation protocol (S2), and following >1 wk of Ca(OH)2 (SC). A log10 transformation of colony forming units
was done since sample bacterial counts are not normally distributed. At S1, 93.55% of canals sampled bacteria. At S2,
52.72% of the cases sampled bacteria. At SC, 14% of the cases cultured bacteria. The McNemar test showed a
significant reduction (p<0.0009) in bacteria between S1 and S2. This was also true between S2 and SC (p< 0.0019). It
was concluded the GT protocol significantly reduced the number of bacteria in the canal but failed to render the
canal bacteria free in more than half of the cases. Ca(OH)2 application significantly further reduced bacteria.
Lastly, large apical instrumentation removed more bacteria than small apical instrumentation.
But as a separate soak after instrumentation.....then the answer should be no.- Fred
We shape and then clean, no?
Surely after instrumentation is the best time to optimise the effects of one’s irrigants? I do a lot of rinsing,
ultrasonication, GP point pumping etc, after I’m finished shaping - Simon
We've all seen the pictures of the extirpated vital pulp dropped into a petrie dish full of bleach.
Magic...in 15 minutes it's all dissolved. There is ample evidence that 6% Sodium hypochlorite is capable of
dissolving tissue. But to try to extrapolate the petrie dish example to use in a root canal flies in the
face of basic physics and hydraulics. It doesn't happen for several reasons. Joey, you 'splain the hocus
pocus to em.
My take is that the most obvious reasons are lack contact of the solution with the remaining tissue; and
rapid depletion of the active ions in the miniscule amount of solution we can instill in a canal. (The
volume of solution that four molar root canals, in an average adult patient, can hold is less than a drop.)
Pumping a liquid down a canal with a file or gutta percha point, in the manner most people think it is
happening, is a myth. Considering the surface tension of the bleach solution and the shape of a canal and
the fact that each canal has at least one vent to the periapical tissues where tissue pressure is pushing
back, we are pretty much limited in depth of penetration to the depth to which we can advance the tip of the
irrigation needle without binding. Further, when a tapered "plunger" is placed into a tapered tube the
solution is not carried significantly deeper into the canal but instead is displaced back out of the canal
by the file, ultrasonic instrument or gutta percha "plunger". This is different than we are used to with a
piston and cylinder apparatus such as a hypodermic syringe where the piston intimately contacts the barrel of
the cylinder along its whole dimension forcing the solution thru the open end. If we accidentally get the
needle to bind in the canal bad things happen.
This is the dilemma that leads to the misinformation presented in many studies purporting that Sodium
hypochlorite is ineffective in reducing the remaining tissue in canals. Truth be told, the solution never
contacted the tissue in sufficient quantity or concentration! Lucci, years ago, demonstrated that proper use
of the solution could completely remove pulp tissue without ANY instrumentation. I would be willing to
predict that studies will show that EndoVac when used properly will do the same. That last mm beyond the
vent holes will still be the problem. It's an improvement but will it be effective in the fins, loops, long
lateral canals and what about the infected dentinal tubules?
Shape, maybe. Clean, as yet to be demonstrated. Reduce the problem to a level the body can handle, most of
the time. Good for us for trying to improve! - Grant
Grant, Terrific well thought out and intelligent reply, as usual.
Only well controlled research will reveal what will work and what is hype. The piece of pulp in a dappen dish
has been a fraudulent exercise which has been misleading dentists for years - Fred
JOE CORRECT ME IF I AM OFF BASE
But... Grant
You have stated the problem better, more concisely and as intelligent as I have ever heard.
These are the exact reasons why Chlor-Xtra will prove to improve endo outcomes and why I have never
been more excited about Endo Irrigation as I am now.
1. lack contact-more prolonged stable release of CL ions
2. surface tension of the bleach solution
limited in depth of penetration-Chlor-Xtra = 2.5 to 3.0 times thinner than standard bleach, means
greater penetration
3. Lucci, years ago, demonstrated that proper use of the solution could completely remove pulp tissue
without ANY instrumentation.- any delivery system will be limited in results without a stable,
powerful penetrating/wetting bleach agent used in concert with better delivery systems. optimal
disinfection is dependant on multiple agents combined with electro/mechanical delivery systems. ITS
A REGIMENT APPROACH
4. the solution never contacted the tissue in sufficient quantity or concentration!-until now!!
5. but will it be effective in the fins, loops, long lateral canals and what about the infected
dentinal tubules? -with proper clinical support... Chlor-Xtra will elevate the level of endo therapy
its all about... better contact angle (easily chemically proved)
significantly greater concentration of CL ions (yields better oxidation)
more effective smear layer removal agents
greater penetration (easily laboratory proved)
more effective delivery systems (Endo-Vac, Safety-Irrigator, Iontophoresis, etc.) - gipvista
GAry,
1. lack contact-more prolonged stable release of CL ions
This is one of the huge issues with standard bleach and the contact angle....see next answer.
2. surface tension of the bleach solution
limited in depth of penetration-Chlor-Xtra = 2.5 to 3.0 times thinner than standard bleach, means greater penetration
No...NOT Thinner...but decrease the contact angle...and it's ability to flow 2-3X greater into areas it could not reach before. Thinner means you changed the viscosity ...which has NOT been changed.
3. Lucci, years ago, demonstrated that proper use of the solution could completely remove pulp tissue without ANY instrumentation.- any delivery system will be limited in results without a stable, powerful penetrating/wetting bleach agent used in concert with better delivery systems. optimal disinfection is dependant on multiple agents combined with electro/mechanical delivery systems. ITS A REGIMENT APPROACH
Lucci's system has big pulp chambers...and don't use the word "completely".....nothing is completely removed in endo. This means we have to instrument an irrigating channel in most teeth today because the needle takes X space to get the irrigant there...it's simply a space problem.
4. the solution never contacted the tissue in sufficient quantity or concentration!-until now!!
We hope....preliminary research done in your lab does indicate favorable results....independant confirmation from multiple sources is required.
5. but will it be effective in the fins, loops, long lateral canals and what about the infected dentinal tubules? -with proper clinical support... Chlor-Xtra will elevate the level of endo therapy
This new irrigant was specifically designed with ALL these issues in mind.....it took a disinfecting, tissue digesting, irrigant we had and modified it surface to deliver MORE chlorine ions AND decreased contact angle.
its all about... better contact angle (easily chemically proved)
significantly greater concentration of CL ions (yields better oxidation)
more effective smear layer removal agents
greater penetration (easily laboratory proved)
more effective delivery systems (Endo-Vac, Safety-Irrigator, Iontophoresis, etc.)
The most effective way to elimiate smear layer is probably NOT to create one to begin with.....ANY instrument that has friction, metal or in my opinion even plastic such as Nylon when wiped against dentin will create smear layer.
Joey D
Fred . I don't do a separate soak.
Bruce asked if the hypo was left in the canal, and mine isn't as it's refreshed many times in 15 minutes so you are
correct that my answer should be no, - Bill
Sorry, I usually just read and learn from posts, but I'd like
clarification on this. If it takes me 10 minutes to instrument a central
incisor am I not gaining anything by leaving NaOCl in canal for a longer
period of time? Thanks, Matt Zweig
re irrigate, re capitulate with files, use hypo in canals when cone fitting, pump the cone, that will take at
least another ten minutes, hence doubling your irrigation time and the patient sees you doing something as well.
I think you need to constantly refresh the irrigant and 10 minutes would not be long enough for me. I'm always doing
something to help the irrigant penetrate as well, be it filing, pumping cones, ultrasonic, endo activator etc
- Bill
Bill, Do you manage to stay patent for all your canals and if so how do you
prevent "pumping" the hypo thro into the periapical tissues? In passing what
apical size are you happy with these days? I ask as I managed to pump some
white stuff through the apex on one occasion, in this instance the patient
really felt uncomfortable with the Ca(Oh) periapically. Fortunately I
managed to wash the white stuff out. Just curious. - Jan
I try to stay patent all the time, #10 file. I very well may pass some hypo through but have not had a reaction to
my knowledge.
Apical size, as small as practical :-)
I like to get Ca(oh)2 through and into lesions, I think, but no real evidence, it helps. I will also irrigate
actively with sterilox into a lesion if I have a big apex.- Bill
A case I did last night only confirms what Joey said, NaOCl has only so much effect. It was a vital, upper first
molar with one canal. I was able to do it in one visit. However, I spent 45 minutes to an hour after I had
instrumented it trying to remove tissue near the foramen using a CPR 5D, files and broaches under the microscope. I
had it opened to a 55.04 (it was even larger) and patent with a 10k but with all the NaOCl out of the bottle, H2O2
3%, REDTA, I could see this blanched tissue which would neither dissolve nor could I snag. Finally, I was able to get
it with a bent broach.
I have always had a bad feeling about one visit vital cases due to either apical bleeding or electronic length being
unreliable or time constraints. Seeing tissue that would have been trapped in a case which I could observe only
confirms my suspicions. Think of what would be left in an ovid or figure 8 canal.
The literature says CaOH2 facilitates tissue removal with NaOCl. Granted that it might obscure lateral canals, tissue
removal is of prime concern - Hank
|
|
