5. Treatment I Flashcards
Development of Apical Periodontitis - after breakdown of the pulpal tissues
• Progresses from crown to apex.
• “Vicious cycle”- inflammation initially arises in particular area > bacteria infiltrates area causing ____ + ____ > adjacent area subsequently becomes inflammed > works its way down the tooth structure accordingly
… Dz progression continues and works its way down until pulp necrosis develops - at this stage, over time complete breakdown of tissues w/in root canal (RC) will occur and space will be further infected with bacteria, fungi, viruses, etc.
microabscesses and necrosis
What’s the radiopaque object? Gutta percha - endo filling material for RCs
• In this case, not an RC
filling. Here, GP was used to trace and identify a ____ (i.e. ____). It’s pretty “harmless” and you’ll be surprised to discover sinus tract origins with this method. Actually gives us good insight regarding dz progression.
sinus tract
chronic apical abscess
2 Goals of Endo Treatment (tx) is to (a) prevent or (b) cure AP:
(A) Prevent AP - for vital cases, like irreversible pulpitis, we may see inflammation, superficial infection + decay, maybe localized area of necrosis (but NO ____ or complete infection of RC system)
• e.g. irreversible pulpitis - has primarily inflammed pulpal tissues inside RC; therefore (t/f) must work ____ to prevent introducing bac that may cause new diseases (e.g. apical periodontitis) in other areas.
Success determined by -
absence of ____ or dz in periradicular tissues in the long-term.
(B) Cure - if AP is already established, our goal is to ____ it.
complete pulp necrosis
aseptically
inflammation
“But what does biological success mean?”
(A) ____ perspective
- Some only view success as survival of the tooth - if it’s functional (e.g can chew regardless of if +/- AP), it’s success. This is similar to views on implant success - functionality is most important.
(B) “True” biological perspective - based on ____ outcomes. For example, if we see root inflammation and bone resorption, we’d want to see signs of healing: ____, restored PD ligament, intact ____. Non- radiographic signs include NO ____ or symptoms post-tx.
Strinberg (continued): Bc past materials were not as biocompatible as today, Strinberg made exceptions for less-than-ideal tx outcomes such as a greatly widened ____ filled w material that extends all the way to the ____.
• vs. today, we have more biocompatible materials, we’d want to maintain the PDL’s original size
as much as possible.
functional biological bone healing/formation lamina dura pain
PDL
root apex
• What’s striking here is the remarkable difference in the % outcome between irreversible pulpitis and ____.
◦These stats underline one of his main takeaways: if you don’t have an infection inside the RC system, as is the case with irr pulpitis (it’s just inflammation in which the pulp is removed because the PT couldn’t take the pain anymore), and so long as there’s no more pathogenic irritants, we can expect an excellent healing rate/ outcome.The 93% means we prevented any AP from developing! Gut job!
“So what about and why the 7% ‘failure’?” Maybe due to a variety of reasons: It could be bc…
• AP may develop from ____ causes: overfilling the RC, pushing out filling material, manifesting of bone
resorptive reactions due to presence of ____, lack of ____ technique while treating PT, or a leaky temporary restoration - all these things can promote vulnerability to bacteria.
• If RC system is exposed post-endo tx, only takes ____ days for bacteria to work its way down to the end of the root filling at the apex - this is why endo is technique sensitive and must be done very meticulously.
AP non-bacterial foreign body aseptic 30
Success rates post-endo tx: AP has lower success rate bc now that bac is inside the RC, not only do we have to work aseptically but NOW we have to ____ in order to eliminate infection - this is much harder than just removing inflammed tissue. Now we have to deal with disinfecting solutions, mechanical removal of bacteria, etc.
• Thanks to better technologies (“bells and whistles” like dental microscopes, hydroscopes, titanium, new instruments, etc.) in endo, these rates are a little bit better today. Nonetheless, still gap btw the 2.
disinfect
How Aseptic Technique Works:
Success criteria met: [X] No \_\_\_\_ [X] Reconstituted \_\_\_\_ [X] Intact \_\_\_\_ [X] No \_\_\_\_ or symptoms [X] \_\_\_\_
AP PDL lamina dura pain durable
AP & Pulp Necro much harder to tx!
- AP and NP always go together, always 2-fold diagnosis (____ diagnosis & ____ diagnosis)
- Images depict actual initial dz progression-+ apical periodontitis, + broken down tissues
• Histo (Riccuci,2010) - shows area of constriction
◦Blue - areas of infection, bacteria
◦Below Red line, infection “stops” bc here body has been “walling off ” infection (immune
defense rxn), which is the ____. It’s a ____, but when it becomes ____ around periradicular tissues (evinced by palpation, tapping top of tooth, etc), then indicates ____ is starting to overwhelm immune defenses. Starts to become symptomatic
pulpal
apical
AP
chronic asymptomatic AP
painful
bacteria
Now we have a tooth, this is the root, this is bacteria (green and red sprinkles) inside the root canal, and this is all a large ____ around the end of the tip. The bone is gone. So, our ideal treatment of these cases with pulp necrosis and AP is to heal these tissues. Ideally, we want to see something like this when we do a 2-year follow up: bone has filled in the destructed areas (may be diff in density for a variety of reasons) but you can see ??? of the bone, PDL outline, filling material inside the tooth, and a definitive restoration that seals everything up. PT has NO symptoms. Great outcome.
• Elimination of the AP - our ____ goal - for a case with pulp necro and AP. So the tissues, perioradicularly, once the infection/irritation inside has been removed, the RC system has the capability to heal bone destruction.
apical periodontitis
biological
Primary Infection - tooth has not been ____ previously
• Secondary infection-In contrast, tooth has received ____ (e.g. imagine a crown restoration has been lost exposing the RC filling, and bacteria can now invade. This means the RC tx has to be redone - it’s called a “re-treatment”
of microbial cells - can’t be ____ specifically bc consists of a mixed population of various bacterial species (some aggressive, some harmless, etc.). So,“____” is an approximation.
infected
tx
quantified
threshold
First, we have a tooth up here with inflammation; at one point, pulp necrosis develops and the infection travels all the way down the RC system. So, by declaration, this tooth now had pulp necro and infection inside the RC space. BUT WE STILL DO NOT SEE AP at this point. We ONLY see AP if the ____ exceeds a critical threshold at which the body needs to mount a response in the peri- rad tissues - a response triggered by bacterial ____ irritating proximal tissues as the bacteria attempt to expand out of the foramen.
So, the body says,“this is too much for me, time to do something about it.” In response, oral cavity begins to form this AP (points to radiolucent lesion on the right-side).
microbial load
endotoxins
So most of the time, what we deal with is ONLY an intraradicular infection - the whole time.
• I’ve only been talking about situations that occur inside the
tooth bc that’s really the majority of cases we find.
◦Yes, I mentioned the possibility of an abscess or external bacteria infiltrating into the tooth - which may cause pain - but, we also have other infections that are NOT intra but are extraradicular.
‣ ExtraR-can be distinguished from an abscess based on finding something like ____ inside a pus-filled area, or we find bac that’s starting to go over into the AP.
‣ Biofilm-a situation where bac might actually lay down a biofilm layer, which can be found inside the RC or even outside the root around the apex. Sometimes this might be something you can’t reach when doing a RC tx.
planktonic bacteria
So now comes RC therapy - basically, the microbial control I’m trying to exert on bac, fungi, etc. inside the RC system. I’ll go in there with my drills, root canal files, sodium hyperchloride, bleach, chlorhexdine, etc. and all these solutions to try to get them out and create a space where we can predicably place a filling material inside the RC that closes it off nicely.
Treatment + (successful tx) - means we were able to reduce the # of microbial cells inside the RC system below the threshold. Now, the body can say, “I’m done with it, I’m over it!”
• Referring to the redline in the graph: the reason this line doesn’t go all the way down to zero is bc it’s almost
____ to render a RC tx that’s completely sterile bc there’s so many ramifications in the RC system assoc w things like connections btw the main canals and/or the presence of biofilms attached to the RC wall.These things make it nearly impossible to get everything out.That’s why we emphasize the word,“____” - NOT sterilization.
impossible
disinfection
Other situations: Able to do microbial control (bring below threshold) but don’t see expected healing -
• Possible reasons why:
◦ The AP can’t heal right away bc bone takes time to turnover.Think of a leg or arm fracture; it takes reasonable amt of time for bone to heal. So, this is why we take radiographs of the perirad areas between ____ mo after tx.
◦Defective sealing of the crown (e.g. due to improper restoration, margins don’t fit, or may have recurrent decay): After tx, endotoxins are no longer circulating in the RC and associated tissues, BUT we may not have sealed tooth correctly, so now it’s open to the oral cavity. Anything like this that compromises the coronal seal and, thus, permits exposure and/or leakage may explain why the AP is not healing as expected.
◦2 diff types of infections -
‣ persistent (not able to clean out everything below threshold)
‣ recurrent (cleaned out good enough)-but healing is disrupted bc an infection from outside the RC makes it way back into the tooth.
6-12
• There’s the primary and secondary colonizers (refers to above image-left side).
So bac can go pretty deep into the tubules. Diff studies have been done that reveal a range ~____ micron (~2mm; essentially the whole length of the root). However, normally we assume that bac are typically present at about ____um deep, or between 100-800um.
◦Complicates tx bc you have to find a way to actually disinfect deep into the dentin to sufficiently reduce the microbial load below threshold.
◦
Typical bac we deal with :
◦____ bac swimming around inside the RC
◦Bac going into the dentinal tubules w/in the dentin
◦Then you have bac that organizes as a ____ (see next slide)
50-2000
400
planktonic
biofilm
