4. Endodontic Microsurgery Treatment Planning Flashcards
Goal of retreatment
to gain ____ to apex, ____ the canal system and ____ tooth structure.
access
disinfect
seal
Goal of surgical retreatment
to gain ____ to apex, expose and ____ complex apical anatomy and ____ tooth structure to prevent re-infection.
access
eliminate
seal
Retreatment indications
When a failure is possible
- a new ____ restoration is planned over an unacceptable previous treatment
So when do we get these cases?
• As an endodontist he gets a lot of cases that are previously treated from restorative colleagues to redo the root canal because:
◦New coronal ____/ new crown is necessary
◦Root canal treatment is not ____- quality is not good and there is a problem/
disease
• These are easy decisions and straightforward
◦Since new crowns are to be done, access is easy
◦The root canal is not done well so we know it’s contaminated and can be improved/
redo
coronal
restoration
acceptable
Retreatment indications
When a failure has occurred
- symptoms ____
- symptoms ____
But sometimes the decision becomes more tricky when you have a nice restoration on the tooth
• like the the very nice fitting crown on the left and a well done RCT
• or like the one on the right, where you have a nice restoration coronally, there is a post, RCT is done well
In these situations what would you do? Are you going to redo the RCT or think about other approaches. It becomes even more tricky if you have done this RCT yourself because you know you did your best last time, disinfecting, finding canals, obturating canals… what else can you do to improve this? So that becomes tricky treatment planning.
persist
develop
Retreatment indications
How to handle inadequate treatment?
____ retreatment is the choice of treatment
The surgery is really sexy like implants where you cut tissues and enjoy because they’re sophisticated procedures. However, no matter what it is,____ retreatments should be considered first when the quality of the RCT is not ____.
LEFT IMAGE: why is the quality is not optimal?
• Missed root: there is a completely missed root there that has to be treated, disinfected, and sealed.
◦So he’s not going to do surgery on this because he can improve the quality of the treatment without causing any damage to the teeth.
non-surgical
non-surgical
good
Decision making
Surgical vs non-surgical retreatments has different steps. So if we learn these steps it will be much easier to decide.
• Similar to diagnosis where we have a form in axium because we have to have this systematic thinking of the diagnosis.
◦Diagnosis starts with ____.
‣ Ex: pt says “I cannot drink cold” and you test the tooth to see if it’s heat sensitive you’re wrong because you have to solve patient problem and look for the cold sensitive tooth.
• Combination of ____ + ____ + ____ + patient’s ____ will lead you to treatment plan.
◦You cannot do Diagnosis and treatment plan, or prognosis and treatment plan. You must consider all of them.
chief complaint
diagnosis
prognosis
clinical skills
decision
Retreatment options
Every case has to be considered ____ because every case is different and this point we have a lot of different options. We can do:
____ retreatment to save the tooth and extend the life of the tooth
____ retreatment
____ is sometimes an important option
◦Sometimes you cannot do that kinda stuff
◦He had a patient that had a lesion on #19 and a couple tumors in the neck area, he’s going to do surgery, chemo and radiation therapy.
◦In these life and death situation maybe ____ would be a better option. We all like to save teeth but sometimes extraction is a better option. These are all valid options.
individually non-surgical surgical extraction extraction
Endodontic outcome
Let’s look at this tooth on this X-ray:
• Do we do ____ retreatment, are you going to go through the crown, take everything out (the post, the filling…), redo the RCT or
• Directly go to the root end and do the ____ procedure or
• ____ the tooth
conventional
surgical
extract
Endodontic outcome
• Look at this X-ray, couple things that we need to look at radiographically:
◦____
‣ Do you like this working length? Can you improve it?
• Yes, I can improve the WL but do I have the skills to improve this WL.
• Or cannot improve the WL
◦If that apex is blocked, transported, if that path is lost you won’t be able to get back into that; so you’re no going to change anything therefore the prognosis may not be the optimal.
____: it’s not that bad!
____: you guys are learning to open the apex large, to 35s and 40s. In this school we believe in opening apex large compared to other schools.
• We open it large so that we can disinfect and irrigate better.
Is there any ____ that we need to find?
____: if the apex is transported, we might not be able to get back in.
working length filling density apical enlargement missed canals procedural errors
Endodontic outcome
____: how is the coronal crown? Is it a good crown? Maybe there’s a broken filling that has been leaking. So you can’t do surgery, you need disinfect and correct this one.
____ under restoration or ____: it could be a fractured tooth, it could be heavily periodontally involved tooth.
New ____ may be needed.
coronal leakage
caries
periodontal pocket
restoration
- Look at working length, we can improve it
- Apical enlargement: it’s enlarged very well but it is transported so there’s is a ____ error. So you may not be able to go through it. If you cannot go through that uncleaned area you’re not improving the RCT.
- There is NO ____ and it is dense .
- Is there any coronal leakage? YES. There is no ____. This is completely open and the bacteria goes back into the canal and re-contaminates.
- It looks like an easy decision. But..next slide
procedural
missed canals
coronal filling
• But if he uses his photoshop skills and put a crown on that, your decision will change.
• Now you’re looking at accessing through the crown and maybe the crown will come off!
Patient will have to go through another crown.
• So you say to patient that hey, I’m going to retreat it and it will cost you 1200 $. You go through the crown and suddenly break the crown during the process, and this is an anterior
tooth!! Now you’re looking at 1200 $ RCT + another 1500 $ crown.
• You have to consider ____, so it’s going to become more difficult to decide.
these
In this decision making process there are 2 factors that we need to consider:
1) ____ factors
2) ____ factors
In endo, these are going to compete all the time. You are trained to go by biological, but there are some situations that technically you won’t be able to accomplish that biological cleaning and disinfection.
These are ____ to each other. Sometimes we think about biology and retreat it, we pick a certain treatment modality, and sometimes we think about technical and we pick something else. There’s no right or wrong answer most of the times.
biological
technical
connected
Let’s look at. Root canal prognosis
• With RCT when the tooth is ____ or when the tooth is necrotic but not ____ and
there’s no ____, we can reach ____% success.
• But when you look at cases where there’s apical periodontitis, the success goes down to
____%. However with new irrigation and instrumentation this numbers goes to maybe
86-88% .
• So there’s a discrepancy when you treating a vital case vs an infected case.
vital infected apical periodontitis 93 75
Outcome of secondary root canal treatment a systematic review of literature
When you look at the retreatment cases, this is a little bit more striking
• when you retreat a case where there’s is no apical periodontitis your success is pretty
high, ____%.
• But when you retreat a case with apical periodontitis, historically that number goes down
to ____%. With new techniques we can reach to 75-78% but we cannot reach 90% and WE WANT TO REACH ABOVE ____% FOR OUR TREATMENT. We want to be able to do a RCT and tell the patient that the chance of you keeping this tooth for another 10 years is 94% which is a good number :)
94
75
90
Why do root canal treatments fail?
Microorganisms; Bacteria as the prime etiology
____ culture -> Complete periapical healing occurred in 94% of cases
____ culture -> Success was just 68%.
Infection of the root canals at the time of obturation had a ____ influence on the endodontic prognosis.
- Dr. Setzer has already shown us this classic article from 97 sjogren study and it was on last exam
- He did RCT on necrotic cases with lesion and he followed up for 5 years. Before he obturate he took the samples, whenever the sample was undetectable bacteria he was effectively removing the bacteria and his success was 94%
- Whenever he still had ____ present in the canal at the time of obturation, his success went down to 68%.
- So today we know that bacteria in the canal plays a significant role in prognosis. So that’s the biology part.
- If you think about this, every single case should be retreated, opened up, disinfected, irrigated, sodium hypochlorite, EDTA, CaOH and obturated..
negative
positive
negative
bacteria
Why do root canal treatments fail?
Microorganisms; ____ as the prime etiology
persistant bacteria
To resist ____ intracanal procedures
To ____ in a drastically changed environment
Undetectable bacteria by culture procedures
bacteria antimicrobial survive 103-104 medications sterilize disinfect
Why do root canal treatments fail? Walled-off abscess, periapical granuloma
Why do teeth with apical periodontitis have a poor prognosis?
There are more numbers and species of ____ in the root canal system of teeth with PAP than teeth without PAP.
It would be more difficult to eliminate bacteria from the root canal system of teeth with PAP.
So why the apical periodontitis cases had less success?
• we talked about bacteria being a factor
• And when the apical periodontitis occurs or by the time we see it on the x-ray (it doesn’t appear within a day or two, it appears after certain time) at that moment we are dealing with number of bacteria being higher and more organized bacteria. Once bacteria form ____, it is difficult to get out of the canal, specially irregular canals.
• So that’s why apical periodontitis cases do not respond to treatment as well as the vital cases.
bacteria
biofilm
Why do root canal treatments fail?
____-off abscess, periapical granuloma
Presence of bacteria in the periradicular tissues is dependent on the depot of bacteria in the root canal.
____ bacteria colonization is heavier and extraradicular bacteria occurrence is more frequent in failed ____ teeth with apical periodontitis.
80% endodontic periradicular lesions heal ____ after proper root canal therapy.
walled
intraradicular
symptomatic
satisfactorily
Decision making
Let’s look at this case from his friend:
• History: Patient had first and second RCT + apical root surgery where you cut the root tip and clean it, but then the patient comes back with infection.
• You are looking at the ____ tracing, the patient describes it as a bubble or
pimple and it’s draining.
• So what’s your thought process?
◦First, you think biology. You want to clean and ____ the canals.
◦He gives this lecture 10X a year and 90% of people say extract the tooth and put
an implant. Because they say this patient had RCT + retreatment + apical surgery
and infection is still going on so this is never going to heal.
◦BUT we know if we remove the bacteria, remove the cause of infection, our body
can heal.
sinus tract
disinfect
Decision Making
What form of Retreatment should we approach?
So his friend actually removed the gutta purcha, disinfected the canal with long term ____ (which is a month or two), ____ the apex.
Look at the follow up 5 years later!
So this is a great example that if we can clean and disinfect the canal, we’re going to have success which is great service for a patient. 5 years later still maintaining the tooth instead of getting an extraction and implant.
CaOH
seal
Why do root canal treatments fail?
Can large periradicular lesions heal following proper non-surgical endodontic therapy?
• previously treated • Pre-op picture: ◦You see a weird filling in the canal ‣ Quality of root canal is bad. • There’s no Working length • We can \_\_\_\_ this canal because initially it wasn’t done well ◦There’s an apical periodontitis ◦There’s a crown ‣ Let’s look at the crown. Can you \_\_\_\_ the tooth without removing too much tooth structure and damaging the crown? Maybe, but we may also damage the crown.
• Post-op picture:
◦If you get back in the original canal, disinfect really well, seal really well, it will heal!
• 12 month and 24 month recall
◦So we have great potential to ____.
◦So for these cases, those are the questions to ask, can you correct the mistake? Can
you seal it well, can you disinfect well?
disinfect
access
heal
Why do root canal treatments fail?
• They categorized cases into two:
1) ____ morphology respected
◦There’s no transportation and no perforations they were able to get back in the original canal.
‣ Shows this example
‣ dr. Kratchman’s case on previous slide would also be a good example
‣ This one had a ____ canal
◦See table: So there’s success after retreating these case.
‣ Without apical periodontitis 92% success
‣ With apical periodontitis 84%
‣ Don’t look at the numbers, look at the difference
root canal
secondary
Why do root canal treatments fail?
2) Root canal morphology altered
◦ Means that you have transportation at the apex and you couldn’t get back to the ____ and you couldn’t clean the canals completely
◦Or there was a ____
◦Or there was a ____ instrument that failed and you couldn’t get back to the canal to disinfect
◦Their success went down ____
◦see table
‣ With apical periodontitis the success was 40%
again don’t look at the numbers. The point is the difference, whenever they couldn’t get into the ____ canal system the success dropped drastically.
canal
perforation
separated
drastically
original
