The Latest Scoop on Endodontic Surgery

You're listening to the Phil Klein Dental Podcast. In the past, if a patient experienced a failed root canal treatment, it wasn't uncommon to refer the patient to an oral surgeon for an apicoectomy. But over the years, we started to realize that in many cases, we don't need to surgerize the tooth to fix the problem. In fact, conventional retreatment or revision endodontics is not only way more conservative than surgery, overall, it's clinically more successful, especially when the failure is due to things like a leaky crown, missed canal, or inadequate obturation. Of course, there are indications for endodontic surgery. But nevertheless, we are not doing nearly as much surgery as we've done in the past. And this is because we have better diagnostic tools and have a better understanding of the etiology of the disease process. To tell us more about endodontic surgery these days is our guest, Dr. Ali Nasseh. Dr. Nasseh received his DDS degree from Northwestern and his certificate in endodontics from Harvard, where he has been a senior clinical faculty member and lecturer for the past 28 years. He lives and practices endodontics in downtown Boston. You can also find him online on his YouTube channel, which is youtube.com slash at AANase. Dr. Nasseh will be joining us in a second, but first, if you're a dentist who understands the importance of diagnostic accuracy and treatment planning, then you're probably thinking about CBCT for your practice. With the advent of CBCT, the limitations of 2D imaging and the clinical guesswork that goes with it are now things of the past. So the question is, which unit should you buy? Of course, you do your research, ask your colleagues, and talk to different companies. But before you make your final decision, check out the models by Merida. As one of the first companies to market in CBCT, Merida has refined its features for simple, accurate positioning and provides multiple acquisition modes and fields of view. Well known for remarkable image clarity, their technology will help you diagnose apical lesions, root fractures, cysts, TMJ, and so much more. So when you're ready to embrace the transformative power of CBCT, check out the state-of-the-art equipment by Merida. To learn more, visit marita.com slash USA. Dr. Nasseh, thanks for joining us today. Thanks for having me, Phil. So to begin, talk to us about surgical endodontics. What falls under that category in typical endodontic therapy? I mean, endodontics as a whole is the process of trying to save teeth. And that's done through the, you know, managing diseases of pulpal origin. We try to do those non-surgically. And then when those non-surgical cases and non-surgical attempts fail, then we manage those. cases surgically. And surgically, that could mean that if there's infection at the end of the root and the tooth that's been already without treated, we try to do an apicoectomy, which involves cutting the root end and then putting a plug at the end of the root, the equivalent of putting a cork in the infected canal, if you will. And then there's all kinds of repair procedures on the side of the root. You could have cervical root resorption. You could have general resorption on the root, invasive cervical root resorption. You could have perforations that are either iatrogenic or due to resorptive defects. So there are a number of surgical ways that you could address these issues. Also, intentional replantation is another way where we can address some of these surgical problems extraorally and then put the tooth back in if we can manage to do this quickly enough. How often is that done these days, intentional replantation? I certainly think it's not done enough. Because the procedure is very predictable. It's just if it's done properly and it's managed correctly, it's very predictable. And it could save still a whole bunch of teeth that are currently being lost for no reason at all. And what are some of the clinical applications for intentional replantation? It's essentially a tooth that is conical enough so it could have a path of draw that could be then the tooth can be reinserted back. But the main point of it is just the organizational skills required to do surgical repair extraordinarily. Based on the literature, you should do this within 15 minutes or 15 to 20 minutes. In my personal standards, it has to be done in less than five minutes, because the less the overall time, the higher the success rate, because you're going to keep the PDL cells alive. So what is the deciding factor to do intentional replantation rather than just make access through the cortical bone and do the apicoectomy that way? So you certainly, you do the intentional replantation in cases in which you cannot do the apicoectomy, which involves usually maybe lower second molars, areas where you have... You may not have access to the root end. You may have anatomical vital structures that may be impeding on your access surgically to the area through an apicoectomy. So that's essentially a final, kind of the last attempt. So based on what we know now, do you think in the past we were too aggressive with apical surgery and many of the cases that we treated surgically back in the day could have been very successfully treated with conventional root canal therapy? Yeah, I think so. And part of the reason why I think endodontic surgery has gotten a bad reputation historically is because historically apical surgery was done by oral surgeons and their understanding of what's causing these diseases were kind of not adequate. It was just used as a panacea for all failed root canal treated cases. Whatever the cause of the failure was, wasn't adequately kind of investigated to begin with. So it could have been missed canals, it could have been... coronal leakage. It could have been just decay up on top of the tooth. And the procedures for these cases were just to go in there, cut the root off, and put a little BB gun preparation at the end of the root with an amalgam retrofill, which worked in many cases. But obviously, if the ideology was not adequately investigated, your treatment plan were not correct. And therefore, usually... success rate is primarily dependent on how good your treatment plan is. And if you've been treatment planning to do apicoectomy on teeth in which the missed canals and there's coronal leakage, you're going to have a lower success rate. So endodontic surgery used to be done quite a bit. And then when a phase where people are like, well, these are not working, so we should just extract these teeth, endodontists came into the field and the research about what's causing success and failure in endodontic cases became a little bit more clear. So we ended up actually picking up on the... of doing revisions and having a fairly high success rate. Studies are showing that, you know, 80 to 90% success rate can be achieved with just non-surgical revisions. And non-surgical revisions work very well in cases of there's missed canals. So then there was a little bit less surgery, but as microsurgical techniques became available combined with better treatment planning. and better materials for these retrofilling, it became like very, the endodontic surgery became super predictable. CBCT has been a big factor too, right? Because that's prevented, that is... allowed us to preclude doing surgical procedures when not necessary. Yeah, CBCTs have been one of the greatest tools in the past 20 years, in my opinion, for better diagnosis. And better diagnosis is the hallmark of better treatment planning. And better treatment planning is the number one source of your success. Therefore, by the transitive properties of logic, these CBCTs have helped improve the success rate of apicoectomies through better case selection. and the application of the right case for the right patient. The research, let's talk about the research. What has that shown over the last 10 years regarding the success rate of conventional retreatment, which you call revision endodontics, versus a surgical procedure where typically back in the day, the general dentist would send it out to the endodontist and say, this was already root canal, it's failing. There's an area of rarefaction, there's pain on percussion, and so forth. the research showing there as far as the difference between success? So again, it goes back to... planning correctly, endodontic retreatment, when done correctly, can have a very high success rate, around 90%, when it's done to the right tooth. If you're choosing the correct tooth in which the cause of the failure is either coronal leakage or inadequate seal or a missed canal and try to revise a tooth like that, then you're going to have a good success because you're addressing the source of the problem. But if you're trying to do a retreatment on a tooth where the problem is just apical, in which case you either have probably like a ledge or a broken instrument at the end, you have a massive post in the middle of the tooth, you try to just use it as a panacea to do retreat every tooth, you're going to weaken those teeth. And plus, many of these cases that could be extra-radicular biofilm where it could have persistent cystic lesions, they're just not going to improve. You're still going to need to have the surgery. So everything goes back into treatment planning, and in this particular case, retreatments would be very successful if the cause of the failure is the things that I mentioned. Now, if you have a case in which the cause of the failure are just apical problems, you have a nice, solid root canal. The canals have all been found, but there is a ledge at the end of the root. There's a hook at the end of the root. There's a broken instrument at the end of the root. But there is a nice crown on top. All of those things are cases in which there's no periodontal disease. Those are all cases in which apicoectomy and surgical management would really give good results. We've done one. I had one of my residents at Harvard come to my office and pull cases that we had done. And we're in the process of publishing this article over like 11 year study on success rate of single rooted. using the surgical technique I've described called the lid technique, the surgical lid technique that combines a couple of calcium silicate cements together. And the retention rate over the 10, 11 years was somewhere to the order of 95%, which kind of is the same as some of the other studies that have been done in Pennsylvania with the 94% in the long run and 97% in the short run using microsurgical techniques. So it's very predictable. Treatment planning is correct. And of course, the obvious telltale signs, as you mentioned, is a leaky crown, an overhang where you know food is getting trapped there and there's leakage and there's signs of decay at the margins. And of course, if the obturation is showing voids, it's not uniformly opaque all the way through the canal system. Between the leakage and the poor obturation, it's pretty obvious that you're getting leakage from the oral environment down into the canal, into the bone. So that's an indication, of course, for retreatment. But back in the day, many of those cases were sent right to the oral surgeon, as you mentioned, and were unnecessarily treated surgically, which that whole mode of treatment has, of course, improved over the day. So in terms of medical contraindications for apical surgery when needed today, what are some of those contraindications that we should be concerned about? Well, I mean, the contraindications clearly would be situations in which you have a medical history of a patient who can't have surgery, a patient who's unable to tolerate it, a patient who doesn't want to have surgery, a patient who has anatomical structures in the area that are going to be high risk for doing a surgery. And, you know, and obviously cases, as we were just talking about, cases in which the source of the failure is not apical. It is coronal. And in those types of cases, it's clearly not indicated to do surgery because either extraction or non-surgical revision would be the proper indication for those kinds of patients. And if you would, Dr. Nasseh, just review some of the clear-cut indications for surgery. Indications for it are any situation in which you're able to do the surgery and you have a tooth where the source of the infection is apical. So coronally, the tooth is clean. There's no decay. There's no leakage. You know, there's good dentin. All the canals have been found, but there is some type of a obstruction of the apex or even the filling looks good, but there's still some persistent infection. As we now know, some of these cases could be extra ridiculous biofilm. Some of these cases could be, you know. bacteria could persist outside the tooth. I mean, you know, you could have infected cysts, you could have, you know, actinomycosis, all kinds of different things that could be present that could maintain an infection. And in cases in which you want to do a biopsy and find out what's going on as well. So those are kind of indications in which you may want to do apical surgery. Where do you make the decision, Dr. Nasseh? And I know it's very hard to answer this question because every case is different and every case has different diagnostic information associated with it. But where do you make the case to extract the tooth? and put an implant in instead of doing a surgical treatment. You know you have to do the surgery because maybe perhaps it had two, it had the original root canal, it had a retreatment, still failing. And this has been going on and bothering the patient, you know, for who knows, five years now. They're kind of playing with this tooth, trying to get it right. So they've had two treatments already, conventional, non-surgical. So where do you say, you know what, we could do the surgery, an apical on this tooth, because it looks like... probably related to a periapical lesion that's just not healing. Or implant. How do you make that decision? In a moment, Dr. Nasseh will return to answer that question. But first, when it comes to patient dental chairs, why choose between sitting or standing when you can have both? Experience the perfect blend of ergonomics and intelligence with the new Forrest 6400 chair from Dentalese. As the highest rising chair in the industry, the 6400 offers unparalleled treatment flexibility, allowing more dentists to practice without pain. Your patients are less likely to interrupt your treatment as they relax in the soothing warmth of adjustable heat and massage, in the comfort of plush ultra-leather cushions and optional neck and knee pillows. And with Aris Intel, the new standard in smart technology, you'll gain insights into practice efficiency, revenue, and maintenance, all from the only chair that monitors data at no extra charge. For more information, contact your local DSX rep or visit dentalese.com. So the decision for me between surgery versus implant is primarily based, again, going back to the etiology of the case. Let's say it's a case that I can manage surgically because the problem is apical. Then, again, there's decisions that I'm going to have to make, and there's decisions that the patient's going to have to make. My decisions are based on the biomechanical strength of the tooth. Can it withstand the type of occlusion this patient has? How's the periodontal situation around this tooth? And can I technically manage the apical problem through surgical access, given the CBCT analysis, how much bone I have to go through? Do I have a chance here? If I do have a chance, I make that determination. And then the next thing would be then to see if the patient has enough motivation. This is a patient who wants to save their own tooth. They don't have any respect for their own natural dentition. Or they can like, you know what, I just don't care. put an implant some people are misinformed some people think that implants have such 100 success rate that that's and it's going to last forever because that's the only thing people think that you know these things all last a certain time and then implants will last forever which is basically a an incorrect kind of analysis of what What it is, it's just there's too much misinformation out there about implants. Implants are a great modality, obviously, and they make a very good option when you cannot save a tooth compared to a bridge, let's say, or a denture. But obviously your own teeth, if it's manageable and you can get a healthy situation going on, you can have a much higher successor with your own tooth rather than implants, which based on deep studies show that, you know, 45% of these patients with implants have peri-implantitis. And perimplantitis is indistinguishable histologically from apical periodontitis, which you see in endo lesions. The only problem is apical periodontitis because it's at the apex. Patients feel it. Perimplantitis, because it drains through the sulcus out, patients don't feel it. And somehow we have this misunderstanding that one is not a problem and the other is a problem. The problem is not certainly histological and physiological. It's just based on the somatic perception of the patient. Yeah, they may feel a little bit more at the apex than up on top. But if we're just worried about the health problems, they will be equivalent. So if you could save your own teeth and be asymptomatic and healthy, it's far better than have an artificial replacement. Yeah, and it seems like every day we're learning more and more about peri-implantitis. The 5 million implants we're putting in a year and tens of millions of implants already out there. We've been doing this for decades. We're starting to see the effects. And it seems to be that peri -implantitis is somewhat pervasive in the implant patient community. Do you know why, Phil? The reason why is because endodontic therapy is complicated. It's complex. It's difficult. Whereas placing a screw in somebody's jaw is a lot easier. And as a result, there is a little bit, and unfortunately, based on the modern situation, it's lucrative in many ways. So people sometimes, I'm not saying this in general, but there are some people that may make the wrong decision. driven by the wrong incentives to provide that solution versus just trying to save the teeth. Yeah, I know you can get away with that, Dr. Nasseh, because we're talking one endodontist to another. So I'm totally fine with everything you're saying because we're talking two endodontists here. But if I was an implant guy, I would have to, I'd probably have to refute that. So I want to ask you about resorption and how that plays a role in endodontic surgery. you're an endodontist, you teach at Harvard, you have your practice, and a patient is sent to you that has what you think is a resorptive process going on, not internal resorption, because that's pretty straightforward. You just got to do the root canal and get rid of the vital tissue. But we're talking about external resorption, something that's starting to eat away the side of the tooth, maybe midway up the root. Does that fall under endodontic surgery, or is that something a periodontist would do? It sure does. I mean, you know, all root repairs are in the realm of endodontic surgery. When it comes to resorptive defects, the real question really is two main things. Number one, the rate of resorption, and number two, the surgical accessibility, which is their location. And considering these two factors, then you can make a decision as to whether the tooth should be managed surgically or should you just kind of monitor it. and see how it goes. Because there's a paucity of data in terms of the external root resorption prognosis in the long run for different types of patients. There's very little we know at this time. We know that the rate of it is... really is increasing dramatically the incidence of it. And that's partially because of the fact that we probably can diagnose it better now with CBCT technology and so on. But in my opinion, also partially because there's the greater use of orthodontics. And as we know, orthodontics about 1% or maybe less than 1% of these kinds of cases end up having disruptive problems. But if the overall incidence of ortho is going up, the prevalence of these types of lesions will have to automatically go up as well. So we're going to be dealing with a lot more of these. But we don't have enough data currently right now with follow-up to see what happens with these cases, how many of them actually become catastrophically problem, how many of them arrest, how many of them revert back. Maybe reverting back doesn't happen quite as much, but... is an expected lifespan? We don't know there's a lot of variability, and some people could go very quick. Within a year or two, it could just completely destroy the tooth, and other people could be 15 years. Is cervical resorption typically more active than lateral resorption, whether it's due to ortho or trauma? I'm not sure if the activity is the same. The problem with cervical root resorption is the problem of location. It's the fact that you are going to transition from the sterile sub... attachment areas into the dirty supra attachment areas. And then that crossing is essentially what creates the microbial component part of it that becomes symptomatic and a problem. So do you think the prevalence of cervical resorption is on the rise due to the popularity of aligners, which is an orthodontic treatment? It must be. I mean, it's in the ortho literature we know, and based on the literature on all resorption, we know that the number one cause of these restorative defects is a combination of trauma, history of trauma, and then it's ortho, and then it's other kinds of movements and trauma and things like that, and then it's lastly idiopathic. So you could make the argument that maybe there is more trauma. I don't know. People are boxing a little bit more or not. But there's certainly more ortho. There's no question about it. You even see people talking about touting about their brackets increasing the rate. So the faster you move these cases, the higher the possibility that you're going to remove the protective shield of precementum and predentin that's over the tooth, and that's going to expose combined with inflammation. These are the two main combinations that cause resorption. You're going to end up getting higher incidence. of resorption root defects. So as we wrap up this podcast, Dr. Nasseh, and thank you very much for your input on so many different areas of surgical endodontics that you covered today, what do you think the reason is why endodontists today are doing so much less surgery than they have in the past? What do you account that to? Well, I think part of the reason is because we've improved the quality of the endo. We have better understanding of what causes failure. The coronal leakage component part of it is so important, so we're doing more retreatment in those kinds of cases. But surgery still has a very, very important place in endodontics. The question here is that using it when it's specified and when it's indicated. And I feel that even though there's less... Now there probably would be a higher success rate on the surgical cases nowadays with a better understanding of the causality and the etiology of the disease process. But I also think that endodontists should be better trained doing surgery in the future because of the fact that as technology is improving, more and more general dentists are going to do non-surgical endocases. And if you don't follow the rules, it doesn't matter what kind of technology you have, you're still going to have failure. And some of those failures, especially with some of the calcium silicate cements, may be more difficult to retreat potentially. That's why an odontologist should be better at doing revision, not revisions, but doing actually apicoectomy in some of these cases that are well-sealed coronally, so they could still save the tooth for another good 10, 15 years. Thank you very much, Dr. Nasseh, for your input. Really enjoyed this podcast. If you're interested in hearing more from Dr. Nasseh, you can certainly check out his content on vivalearning.com. Go to the search field and type in Naseh, N-A-S-S-E-H, or check out his YouTube channel, youtube.com. at AANase, and you'll find his videos there. Thank you very much. Thank you so much. If you're enjoying this podcast, please leave a review or follow us on your favorite podcast platform. It's a great way to support our program and spread the word to others. Thanks so much for listening. See you in the next episode.