IADS SCORE Webinar: Prof. Mandeep Duggal

Ajouté : 2026-04-29

[00:00:24]is somebody starting the meeting?

[00:00:29]Yes, we are now live live on YouTube. We are starting in five minutes with the webinar. So, we are sending the link to all the participant.

[00:05:03]Hello everyone and welcome back to the pediatric dentistry webinar series. My name is Omar and I am the webinar director at the score committee. It's a pleasure to have you with us today for the third session of this series. Before we begin, I would like to briefly introduce the International Association of Dental Students, IADS, a global organization that connects dental students worldwide and promotes academic exchange, professional development and international collaboration. The webinar series is organized under the score office of IADS, the standing committee on research and education which focuses on research, education and global engagement. Through score initiatives, students have the opportunity to learn from experts and expand their academic experience. We are pleased to continue this pediatric dentistry series, a specialtity that plays a key role in promoting oral health from an early age and ensuring positive dental experiences for children. We hope today's session will be insightful and beneficial. It's a great pleasure to welcome Profandib Dugal today and we sincerely thank him for joining us and sharing his expertise. to introduce our speaker and guide us through the session. I would now like to hand over to my colleague Emiliana.

[00:06:31]>> Okay. Hi everyone and welcome back for this session. It's my pleasure to introduce today's speaker professor maniple.

[00:06:40]Uh, Professor Dagal obtained his dental degree and specialist training in ped dentistry in India before moving to the United Kingdom where he was awarded uh the fellowship in dental surgery and of the Royal College of Surgeon of England and the PhD from the University of Leeds. In 1999 he was appointed professor and chair of child dental health at the lead dental college institute where uh he led a post-graduate program uh with international recognition throughout his distinguished career professor dagal uh asel several senior academic and leadership position worldwide. This includes his role as professor of pediatric dentistry at the National University of Singapore where he also served as uh vice dean and faculty research director um and uh the national university uh of center for health. In 2021, he was appointed a founding dean of uh college of dental medicine at Qatar University, a role he held until January 2026.

[00:07:53]He is currently professor of pediatric dentistry at King's College in London.

[00:07:59]Uh, professor Dagger has made outstanding contribution to research and education with over 200 publication in international journals and authorship of widely acclaimed textbook including restorative techniques in pediatric dentistry translated into uh seven languages and pediatric dentistry by Oxford uh now uh in its fifth edition.

[00:08:24]His research interests focus on cardiology and translational research in clinical pediatric dentistry including dental traumatology, regenerative antodontics and auto transplantation.

[00:08:37]Today I will present a lecture entitled management of nonvital immature incizers after trauma. Uh is revitalization the answer?

[00:08:49]Uh this talk will explore the challenges associated with severe uh dental trauma in immature permanent incizers particularly when pulp necrosis compromises fer root development. Uh so uh without further ado I will leave the floor to the professor Daga. Uh thank you for joining us today and so the floor is yours.

[00:09:15]>> Thank you very much. I will now share my screen. Just give me a minute.

[00:09:34]Can you see my screen now?

[00:09:35]>> Yeah.

[00:09:36]>> Great. Thank you very much for your very kind introduction. Um, I'm joining you today from uh very unusually warm and sunny London. Uh usually we have a saying that in London we only have two types of weather. It's either raining or about to but uh today we have excellent sunshine for the last few days and u it's actually a day that I shouldn't be sitting here giving a webinar. I should be outside doing something else but it's a pleasure to talk to you. Uh just a few weeks ago I was in Qatar uh where I was for five years. Uh had a beautiful place. You can see the view from our balcony just in case anybody ever wants to visit Qatar. It's a beautiful country. Uh we had a wonderful dental school there uh with a fantastic labs. I think some people from IADS visited us there as well. And we have really a beautiful dental school uh with very digital uh curriculum. Uh so our students learn digital dentistry from a very early stage. Uh and then the same digital dentistry goes into the clinics and they also practice very much the digital dentistry. uh the first class ever from Qatar graduated in 2005 in May and it was really one of the proudest moments I think for the country to graduate the first group of dentists from Qatar and following that now I decided to move back to London. Uh you can follow the students there are very active on social media and you can follow them uh on their Instagram page.

[00:11:20]So I was thinking what to talk to you about today and uh I just wanted to give you a a flavor of something which is one of my favorite topics and that is dental trauma. I mean dental trauma is very complex and complicated but I'm going to talk about one particular aspect of dental trauma which is what happens to the pulp after dental trauma and what do we do if the pulp actually becomes nonvital and that is a very important question because as lot of you know that in young children if the pulp becomes nonvital the root develop velopment stops and the root stays immature. So how do you treat what are the strategies to treat an immature root canal? And you might have read in the recent literature for the from the last 10 years that revitalization has become a big topic that you know we feel that instead of doing root canal treatment uh with gaperka or whatever we can revitalize the root canal with stem cells and with scaffolds.

[00:12:37]So is revital where is where are we now with revitalization?

[00:12:42]Are we at a stage where it is a mainstream treatment and if not why not where are the deficiencies in revitalization and what can we do to make it more predictable in the future.

[00:12:59]I will give you very much a pediatric dentist perspective because children have some unique challenges. One of the unique challenges in a child is that whenever there is a severe trauma like this, it's not the trauma that's the problem. I can fix that problem in the mouth. The biggest challenge in children is that the root development is incomplete.

[00:13:27]That means that the crown root ratio is very poor. There is not enough cementum.

[00:13:31]There's not enough dentine. The apex is wide open. If the root becomes if the tooth becomes nonvital at this stage, then the root development will stop and any further and intervention in such cases will not work. So the biggest challenge in immature when I say immature what I mean is teeth with incomplete root development that become nonvital. So that is an immature nonvital permanent incizer.

[00:14:10]If you go back and look at this root now what challenges will you face as a clinician? Well, first of all, the root has thin dentine walls which is liable to fracture under physiological forces.

[00:14:24]Have a look again. You can see very thin dentine walls here which means there is a fracture already physiologically because it's a very weak root. Secondly, it has a wide open apex. You can see wide open apex which makes it almost impossible to do anyodontic intervention. And lastly, a wide root canal space. How would you fill such a huge root canal space in this tooth and whatever you do because there is insufficient amount of cementum and denting the tooth will remain vulnerable to future fractures. So that is the challenge when you treat nonvital immature permanent incizes after trauma.

[00:15:11]But what I always teach my students is that think as a scientist.

[00:15:19]We can only be good clinicians if we apply scientifically correct procedures for our patient. If we understand healing, if we understand growth and development and if we understand what tissues are involved in trauma and how we can help as clinicians to heal those tissues. So we should always try to translate good science into clinical excellence so that the children can get a biological long-term sustainable outcome. Now when a tooth becomes nonvital an immature tooth what have we done traditionally here you see it's a wide open apex and what we have done traditionally is we have put things like MTA at the top or calcium hydroxide then we have opturated these teeth but the problem with tradition is that these teeth are so weak weak that they remain vulnerable to root fractures in the future. So even after such endoderodontic treatment because the tooth structure is so weak the one day the patient will bite into something hard and there is usually a fracture at the cementto enamel junction and this is the biggest problem and the reason is that when you do these treatments what this treatment does is it allows you to fill a root canal. That's all it does. It does not give you any structural qualitative increase in root dimensions. So this treatment does not make the teeth stronger.

[00:17:08]It only allows you to deal with a empty root canal space and that's it. And that is where the endodontist get all their work from. But it does not give you any qualitative increase in root dimensions.

[00:17:24]Now the problem is that if you look at the literature it is very clear that the incidence of root fractures is very high after endodontic management of immature teeth. So the more immature the root is the higher the risk of root fractures. So you can see the most mature roots less chance of root fracture. The most immature roots almost 80% risk of root fractures with conventional nonvital treatments that we do for children. So what I want to talk about today is why is it so important that we allow the pulp wherever possible to heal so that and the treatments that we do are aimed at facilitating pulp healing.

[00:18:23]That's number one. The second thing is what is the role of calcium hydroxide and MTA in achieving good outcomes for nonvital teeth and thirdly I'm going to do a critical appraisal of treatments we which we generally call as regenerative endodontics but the current terminology is revitalization treatments but they also commonly referred to in the literature as regenerative therapies in immature teeth. So this is an attempt to revitalize the root canal after it has become nonvital.

[00:19:09]Now what do we know? First of all, the most important thing that I want you to remember is that pulp healing is critical for a good outcome of traumatized teeth with incomplete root development. Wherever possible, we should try to get the pulp to heal cuz once the pulp does not heal, the root development will completely stop.

[00:19:36]Remember this. No pulp, no further root development. If the tooth becomes non vital at this stage, you take an X-ray 5 years later, the root development will be no further. It is not possible to get continued root development. If the tooth becomes nonvital, that's the first thing. And if you look at this case here, it's the same one here. I've taken this tooth out and you can see it's a very weak tooth, very insufficient crown root ratio, poor dentine, poor cementum, wide open apex. This tooth has a hopeless long-term prognosis. So, we need the pulp. Why do we need the pulp?

[00:20:24]There are three cells which are involved in root development.

[00:20:30]One is epithelium.

[00:20:32]the epithelial root sheath of of Herwig.

[00:20:37]What does the epithelial root sheet do?

[00:20:40]It maps the length of the root. It tells you how long the root is going to be.

[00:20:46]Once the epithelial root sheet has mapped the length of the root, odontoblast will differentiate to make dentine and cement blast will differentiate to make cementum.

[00:20:58]All these three cells here need blood to work. If there is no blood supply and the tooth is not vital, there will be no further root development in the tooth.

[00:21:12]What I want to see as a pediatric dentist. When a patient comes to me with trauma, I want they come to me like this wide open apex, immature root development, thin dentine walls. At a follow-up visit, I'm happy if I see continued root development. The root is becoming longer. At the next visit, you can say that there is more deposition of dentine and cementum. At the following review visit, the root has become longer. There is more dentine, more cementum. And at the final review visit, the apex is now closed. This means that from here the tooth healed, the pulp healed in this patient. If there was no healing, root development would have stopped at that stage. But because now the pulp has healed, it has gone on to develop the root and form enamel dentine and closure of the apex which we call as aexogenesis.

[00:22:24]So aexogenesis is only possible if the tooth retains a blood supply.

[00:22:32]That is why whenever you see a traumatized tooth where the pulp is involved like in this case of a complicated crown fracture, we must always think in terms of pulp management, not root canal treatment.

[00:22:51]What do I mean by pulp management? I mean that we need to see if we can save this pulp because if we can save it there will be continued root development.

[00:23:03]Whatever treatments we do should aim to facilitate pulp healing. This is the main thing in pediatric dentistry. We must do treatments to facilitate healing of the pulp. And I think you had lectures from Dr. Hani recently where he talked about I think pulp management. I saw his name somewhere on your posters.

[00:23:29]But I'm just going to briefly recap with you what what do I mean by facilitating pulp healing? Well, look at this case.

[00:23:39]This patient was referred to me with an exposed pulp and a fracture here. This is what we call as a complicated crown root fracture. What does that mean? This palatal fragment is fractured below the gum onto the root.

[00:24:01]When I have when I take an X-ray, the apex is wide open and the root development is incomplete.

[00:24:10]Now what I've done is now I have taken the palatal fragment off. You can see that the fracture line goes onto the surface of the root. But what to do with this pulp? Well, this pulp is contaminated. So, all you need to do is gently clean the pulp with your high-speed handpiece a little bit, 1 mm, 2 mm, till you get normal bleeding.

[00:24:37]Once you get normal bleeding like now you put calcium hydro oxide glass and what I've done is because I want to build the tooth and the fracture line is going below the gum. You should never put composite blindly before under the gum. So I've done a little bit of electro surgery so I can see the fracture line here and now I will restore the tooth with composite resin.

[00:25:07]So I have done electro surgery, pulpotomy, minimal pulpotomy, composite resin and you can see now this was the tooth with an open apex incomplete root development pulpotomy done. 6 months later, 12 months later, there is continued root development, which means that with my treatment, I removed the contaminated pulp, but I preserved the normal pulp, which survived and healed and that is why the root development could continue normally. So these types of treatments which facilitate pulp healing are very important in pediatric dentistry. And you can see here a very difficult case where the patient came to me 4 days after the trauma wide open apex pulp exposure. I still did a pulpotomy here because if I do root canal here the root development will stop and we have a very weak root.

[00:26:16]So I did a pulpotomy and you can now see the root development is complete after my pulpotomy but eventually in this case it doesn't normally happen. In this case the pulp did become nonvital eventually but now the root treatment will have a very good outcome because the root development has already completed. So because I did my palpotomy here I allowed the root development to continue. Once the root development is complete the patient developed parapical symptoms I extrapated the pulp and started the root treatment. But now it's a simple straightforward root canal treatment which any dentist can do with a completed root development and closed apex. So this is the beauty of preserving the pulp in these cases.

[00:27:10]The question is what do you do if the pulp becomes nonvital because now you've ended up with this big problem of the three things which I already told you about thin dentine walls wide open apex wide root canal spaces how do you manage these three things well a wide open apex is not it has been traditionally managed by using calcium hydroxide. What people have done the technique is called calcium hydroxide epoxification.

[00:27:50]We don't use it now. But that's what I grew up as a dentist doing. But I will tell you later why we don't use it now.

[00:27:59]What we used to do put calcium hydroxide for a long period of time in the root canal and the calcium hydroxide irritated the apex and produced a calcific.

[00:28:13]And once you got a calcific barrier, you then opturated the root canal with gap perka. And this technique was called a pexification with calcium hydroxide. Now I just said to you 2 minutes earlier we don't use it anymore. Why? Well the problem is that we now understand that if you use calcium hydroxide in the root canal for a long period of time for epexification.

[00:28:44]Calcium hydroxide can have detrimental effect on dentine.

[00:28:49]Why? Because calcium hydroxide is highly alkaline. It has a pH of 13. And when you put it in a root canal, it comes into contact with dentine which has collagen in it and a highly alkaline substance like calcium hydroxide. It denatures the collagen and once the collagen is denatured in the dentine the dentinal wall the dentine becomes liable to root fracture. It desiccates, it dries up and it becomes very prone to root fractures. So now we know from research that if you use calcium hydroxide for too long in the root canal, the main tensile fracture strength of dentine is reduced by half within 2 months. So you should not use calcium hydroxide in the root canal for a long period of time. And this is what you see. You see root fractures after calcium hydroxide epoxification at the cementto enamel junction which are very very common after calcium hydroxide epoxification.

[00:30:02]So the long-term use of calcium hydroxide in immature root roots is no longer advocated.

[00:30:10]So how do you achieve a barrier if the root is wide has a wide open apex? You can't put a root filling in because it will go through the apex. you will not be able to get an apical seal. So how do we create a barrier at the apex? Well, now we use mineral triioxide aggregate.

[00:30:31]I just want you to read this article.

[00:30:34]This is the European guidelines on this topic which I wrote with my team called interventions for endodontic management of nonvital traumatized immature anterior teeth. These are the guidelines of the European Academy of Pediatric Dentistry. And in these guidelines for the first time we said that calcium hydroxide should not be used for the long t long term. Wherever possible we should use MTA which is mineralide aggregate which is a triricalium silicate to create a barrier at the apex. And once you create the barrier with MTA, you opturate the root canal space with gutapura. And finally, you create a good coronal seal to prevent reinfection. And I will show you how that works like this. You see in this case now that we don't do apexification anymore. We use MTA which now comes in many forms. When I first started, it used to come in a powder.

[00:31:44]You mix it with liquid. It still comes like that but now it even comes as a putty. You can use it as a putty which is much easier to use and we can use these special carriers. They are like amalgam carriers but they are disposable MTA carriers. And you can pick up your MTA. You can set the working length on this needle here. So if the working length of your root canal is 22 mm, you set it at 21.5.

[00:32:14]You deposit the MTA around the apex.

[00:32:17]Then you keep reducing the working length till you have put a 4 mm MTA barrier at the top. Once you put the MTA barrier at the top, you allow it to set and then you can opturate the rest of the root canal with gutaperka in that visit or the following visit. So you can see here wide open apex incomplete root development and here you can see my gut per my MTA plug at the top there and after doing my MTA plug I have opturated the rest of the root kal with ga perka but please note that when you do a root filling it is called a root filling for a reason. It should stay in the root canal. I have seen students fill guta perka up to here. No, the gutaperka should remain in the root canal. The rest should be a coronal seal.

[00:33:19]90% of root canals fail because of coronal leakage and reinfection.

[00:33:26]So what you need to do finish the get up your root filling in the root canal. I usually then put three more layers to prevent coronal leakage. I put a layer of GIC called vitra bond. Then I put another layer of Fuji 9. And finally I put composite. So I use a triple coronal seal to prevent any coronal leakage after my root canal treatment. So we don't use calcium hydroxide anymore. We now prefer the use of triricalium silicates like MTA like biodentine to make apical seal so that we can then opturate the the teeth with gata. So this is now the new trend. However, the problem is that even with MTA, you can close the apex, but you cannot qualitatively increase the root dimensions.

[00:34:29]You remember I said at the start of my talk that the treatments that we do for nonvital teeth like endodonic management, they don't facilitate continued root development. All they do is they allow us to close the apex so you can push a root filling so it doesn't come out through your nose. Basically, that's all they do, right?

[00:34:55]Just give you an apical seal. That's all they do. But they don't give you any improvement in qualitative width or strength of the root canal. Now to overcome this problem a treatment was thought of called regenerative endodontics.

[00:35:22]Even though many people still call it regenerative endodontics, the terminology now tends to be more towards revitalization.

[00:35:33]And when this treatment was introduced, it reflected a paradigm shift in management of nonvital young permanent incizers. It was a huge shift, a massive leap to manage nonvital teeth through revitalization.

[00:35:53]And the first article ever to be published on this was here. You can see I can't see the year. I can't remember the year but it was very very early. Oh look 2004.

[00:36:08]It was published in 2004.

[00:36:10]It was called revascularization of immature permanent teeth. A new treatment protocol.

[00:36:18]What was this treatment protocol? Well, this treatment protocol was what we now know as revitalization.

[00:36:27]And I will go through it with you step by step. What is revitalization?

[00:36:33]What is the idea behind revitalization?

[00:36:36]The idea behind revitalization is that instead of doing root filling in teeth which are immature and nonvital, instead of putting an artificial root filling in, is it possible to revitalize them with new tissue, body's own tissue?

[00:36:59]Would that be a better option in these cases?

[00:37:04]Could we expect some form of pulp to be regenerated inside a nonvital immature permanent incizer?

[00:37:18]So the rationale for regenerative therapy was and I want you to read this very carefully because this is what we will measure its success against.

[00:37:31]I will read it fully.

[00:37:33]Through the repopulation of the root canal space with vital tissue.

[00:37:38]This technique aims to promote continued root development.

[00:37:43]You remember I said when you do a root filling there is no qualitative increase in root dimension. There is no root lengthening nothing. So what this treatment says it aims to promote continued root development. Number one.

[00:37:58]Number two to thicken the dentine walls with new tissue thereby improving the long-term prognosis of these teeth. So this treatment was revolutionary in its thought.

[00:38:14]Don't get carried away because I'm going to tell you that it doesn't work in most cases. But I will also tell you where it works and where it doesn't work. But the concept was bring some vital tissue in the root canal. This vital tissue will allow hopefully the root to develop, the dentine to develop and the tooth will become stronger and longer.

[00:38:37]and then all the problems with nonvital immature teeth will be solved. So the long-term prognosis will become very very good. Now let me share with you the technique that I use that we developed in leads first many years ago with myself and professor Hani Nazal we made this technique in leads so what we did in these cases we took the teeth which were nonvital with a parapical lesion we opened them up we irrigated them cleaned the root canal with 2.5% sodium hypocchloride Right. Then we took a combination of three antibiotics metronidazol, cyproloxicellin and moninocycl.

[00:39:28]Now initially we called it tribiodent because it was three antibiotics.

[00:39:36]But eventually we realized that minocycl being a tetracycline.

[00:39:42]If you put it in the root canal, it discolors the teeth.

[00:39:46]So we removed the minocycline and instead of tribiodent, we called it bibbiodent. It's it was something we used a combination of metroniditool which is an anorobic fighting antibiotic cyprluxilin which is a broadspectctrum antibiotic. We combine these two antibiotics in sterile water.

[00:40:12]We used the venflon, removed the metal bit, used the plastic bit here. And using this plastic, the syringe of the plastic, we filled the root canal with the double antibiotic cream. So we put munocyc and cyprofluxis inside the root canal. We then sealed the tooth with a cotton pledge and glass cement for two weeks or until a time the parapical lesion had disappeared.

[00:40:49]Once the parapical lesion had disappeared, we brought the patient back.

[00:40:55]We irrigated the antibiotics out of the root canal. So you flushed the antibiotic out like this with normal saline.

[00:41:05]Then what we did we took EDTA and I'm sure you all know EDTA and we use I will tell you later why we use EDTA. We irrigated with EDTA and after irrigation with EDTA we took a sharp long instrument and after giving local anesthetic we pushed it through the apex creating trauma around the apex and inducing bleeding into the root canal.

[00:41:42]Once the root canal was full of blood, we put glass rhyme and sealed the tooth up with composite resin or we use Portland cement because you should not use MTA in the coronal part of teeth because MTA discolors.

[00:42:05]Portland cement is MTA but with bismouth oxide taken out so it does not discolor.

[00:42:11]So we use Portland cement on top of the bleeding pulp like this, glass hanger and composite resin and we seal this tooth up. Now some of you will be wondering why do you want to do that?

[00:42:27]Why do you want to bleed into the root canal? What happens? Well, I'll tell you what happens.

[00:42:36]Those of you who know a little bit about cell biology and how tissues are made, you know these days scientists can make skin in the lab and that skin can be transplanted in burns patients. You know people who get burnt, you can put artificial skin on their burns once the burns have been treated for rehabilitation.

[00:43:05]How do you grow a tissue? How do you make a tissue? Let it be skin for example. How do you make it? Well, you need three things to make a tissue.

[00:43:18]First of all, you need plur potent stem cells. You need stem cells which have the potential to form the tissue you want.

[00:43:34]Second thing is you need because stem cells can't form something you want unless you tell them what you want right so you have to tell them what you want and how do you tell them you can't talk to them right so you have to send them some signal and what is this signal these signals are what we call as bone morphagenetic proteins or bio signaling molecules so you tell the stem cells, I want epidermis cells.

[00:44:08]You tell the stem cells, I want fi fibbrin.

[00:44:13]I want dermis. I want collagen.

[00:44:17]And gradually you can build a skin because you give the right signals to the stem cells.

[00:44:25]But stem cells cannot grow into a void.

[00:44:30]They need some form of a scaffold into which they can grow. So you have to give them a scaffold, something into which the stem cells can differentiate into the tissues that you want.

[00:44:45]And in root canal you need one more thing.

[00:44:52]You know root canals are dirty spaces.

[00:44:56]So you need complete sterilization.

[00:45:00]That is why we use antibiotic paste in the root canal to achieve not disinfection but sterilization complete removal of all bacteria from the root canal. Once this is done the idea is that it might be possible to generate pulpike tissue in the root canal. So what what is it? How why what is the thought? Well, the thought is we now know that around the apex of an immature root there is a structure. It's called scap.

[00:45:45]S c a p.

[00:45:49]What is scap?

[00:45:52]Stem cells of the apical pillar.

[00:45:56]So around the apex of an immature wide apex tooth there is an area which is rich in stem cells.

[00:46:05]And the idea is that when you bleed when you poke the apex you bring the blood up which brings into the root canal the stem cells. So the stem cells come up into the root canal with the bleeding that you have induced.

[00:46:27]So hemorrhage that you have induced from the granular apical area will bring stem cells into the root canal. Once the stem cells have come into the root canal, the idea is they will be able to differentiate into giving us some form of tissue in the root canal. That is an idea generally. But the biggest problem we have is that we because we don't have signaling molecules.

[00:47:02]We just induce bleeding into the root canal.

[00:47:06]There is no controlled mechanism.

[00:47:09]So what actually grows into the root canal?

[00:47:14]This is one of my patients.

[00:47:17]I did revitalization for this patient 6 months before I extracted the tooth.

[00:47:24]6 months later, we decided to extract the tooth because we were going to because we wanted to say do auto transplantation instead of this because we weren't happy that it was developing properly. When I extracted this tooth, you can see in the socket there was something there.

[00:47:45]You can see that and when we took it out that had what that is what had grown into the root canal after the revitalization procedure. So the question is what is it that grows into the root root canal when you do revitalization?

[00:48:07]It's not pulp.

[00:48:09]It is healing tissue. You get bone, you get fibroblast, blood vessels, collagen, but you don't get odontoblasts and you also get bone and cementum coming into the root canal. But what is important is that the root canal with your treatment gets full of something which at the moment we don't know if it is good or bad but it is the body's healing tissue that fills the root canal after revitalization.

[00:48:46]So you can fill the root canal up but we at the moment there is not enough research to tell us if this tissue in the long term will be good or bad. We don't know. So the why did this technique come into being. I just want to share with you some things which you might find it a little bit difficult to understand so far in your undergraduate career.

[00:49:14]uh because this is more what we teach our post-graduates in pediatric dentistry but I will explain to you in a very uh I hope in simple terms so that you can understand well the first case published about revascularization or revitalization was a nonvital preolar and they did revitalization in this and what they reported was that after revitalization treatment there was continued root development and pulmonal obliteration.

[00:49:47]Now please remember this preolar became nonvital because it had a dense evaginatus.

[00:50:00]Do you all understand dense evaginatus?

[00:50:02]Right? the the tooth had a cusp which broke off and the tooth became nonvital and beca and then they did revitalization. There was no trauma.

[00:50:14]This was what we call as a developmental anomaly. It was a developmental anomaly, not dental trauma.

[00:50:23]But what we did was we took this and started to apply it to dental trauma. Right? So I want to explain to you today is there a difference in the outcome if you do revitalization in development anomalies versus dental trauma.

[00:50:48]Is there a difference outcome? What is the difference between an developmental anomaly and dental trauma which might make a difference in prognosis of revitalization?

[00:51:02]So let's look at it. First of all, let me take you back a little bit to cell biology and embryology. I know you guys hate hated this lecture and this course in your undergraduate studies. We all did. But when you grow up, it comes back to haunt you. Because what we don't realize at that time, we find it boring and awful is what is real science.

[00:51:32]If you remember when the tooth germ is developing, this is the enamel organ. What happens first?

[00:51:42]The first thing that comes are amoblasts or what we call as inner enamel epithelium.

[00:51:52]Before the amolast appear this clump of cells here is what we call as undifferentiated misenymal cells.

[00:52:03]Once the epithelium is formed, the epithelium has what we call a embryionic organizing influence.

[00:52:15]It organizes the undifferentiated misenymal cells into odontoblasts and cementtolast. So this part becomes the crown and this part becomes the root.

[00:52:29]If there is no epithelium, the undifferentiated misenymal cells cannot differentiate it to rodontolast and cementlast because there will be no embryionic organizing influence from the epithelium. Epithelium is essential so that undifferentiated misenymal cells can differentiate.

[00:52:54]Now you will think where how does that fit in with trauma and with revitalization? I mean it's got nothing to do with it but it has and it explains the difference between the outcomes for developmental defects and carries and trauma.

[00:53:15]Now I told you earlier that you need three things for root development. Herwig epithelial root sheath adontolast cementtolast when there is no trauma when the tooth has become non vital because of say dense evaginatus or carries there is no trauma to the herwig epithelial root sheath the epithelial root sheath is intact when there is dental trauma because the periodontal ligament is damaged the Herwig epithelial root sheath usually becomes nonviable or becomes damaged.

[00:54:02]Now in the first instance if the herwig epithelial root is intact it is possible that with revitalization the undifferiated cells can differentiate into more organized tissue because the embryionic influence of epithelium is there in trauma if there is no hertoric epithelial root that becomes takes away the embryionic organizing influence of the epithelium.

[00:54:34]So it means that the cells will not differentiate into blast and cement blast. Now let me show you clinical outcomes. Why is it importance to have why is it so important to have the organizing influence of the epithelium?

[00:54:52]Let's look at cases.

[00:54:54]This is showing healing only, right? Because epithelial root sheath is nonviable.

[00:55:05]If the epithelial root sheath is nonviable, there are only two outcomes possible. One, healing only because you put antibiotics in the root canal.

[00:55:14]Second, undifferentiated tissue will come into the root canal because there's no organized tissue because there's no epithelium. So, here's one of my patients pre-operative dental trauma.

[00:55:27]I've done regenerative revitalization induced bleeding with Portland cement and composite. Here you have blood. 3 months 24 months you can see there is no further root development but complete healing around the apex.

[00:55:50]So in this case what does it mean? It means heric epithelial root is damaged.

[00:55:57]There's going to be no further root development. But because I have tissue inside the root canal, it's probably and I put antibiotics in before I've got complete healing.

[00:56:08]Case number two, periapical lesion, open apex, incomplete root development, revitalization, 36 month outcome, complete healing.

[00:56:22]But no further root develop. Why?

[00:56:26]Probably her epithelial root sheath was dead in this case. Healing only. Now look what happens when undifferentiated tissue grows into the root canal. Here you have a patient, one of my patient who has a very wide open apex, massive root canal. The tooth became nonvital.

[00:56:47]I did regeneration, revitalization.

[00:56:50]You can see in this case some healing is taking place and some deposition of undifferiated tissue in the root canal. This is at the time of trauma. This is 6 years post-operative.

[00:57:06]You can see lot of undifferentiated tissue has grown inside the root canal in this case. Right? So in cases of where the epithelial root teeth is nonviable revitalization either gives you healing or undifferiated tissue. Now look to what happens if the epithelial root sheath is viable.

[00:57:35]Here is a patient whose tooth became nonvital because the patient had a dense invaginatus a dense indente right I've done reagitalization posttop 18 months posttop look how much root development has happened in this case after revitalization why because there was no trauma The tooth became nonvital because of a developmental anomaly. There is now viable herwig epithelial root sheath and the tooth has become has continued root development. So it works in some cases.

[00:58:22]Now I will show you another case of dense evaginators. In this case the patient was asymptomatic.

[00:58:28]The patient came to me only with discolored tooth, no infection. In the second case, it's a case of dense invaginatus again. But in this case, the patient came to me with a large buckle.

[00:58:44]So because of the absess, the herwig epithelial root sheath was damaged. And after revitalization, you see 5 years posttop complete healing but no further root development. Healing takes place in these cases because you have done antibiotic treatment and you have induced bleeding into the root canal.

[00:59:07]And we have published a study a clinical study in journal international andodontic journal on immature teeth which showed that in immature teeth there is 100% perodontal healing but no root development because of the damage to the heritic epithelial root shape.

[00:59:31]So revitalization does it give us continued root development? It can if herwig epithelial root sheet is preserved.

[00:59:43]It doesn't if the herwig epithelial root sheet is not preserved. Does it give us thickening of the dentinal walls? It does in some cases. It doesn't in another cases. It's unpredictable outcome. So we don't know at the moment how predictable this technique is. It is the unpredictability of outcome that is a problem. Is it a true endodonic success or is the tooth merely surviving till a later date when it will become absessed? We don't know because the studies are not there at the moment.

[01:00:23]We can predict the outcome in developmental defects but we cannot predict the outcome if the herwig epithelial root sheet is not preserved.

[01:00:33]It's unpredictable and I always like this slide you know that this professor has written something very complicated here and the outcome is very complicated and then in the middle he's the student is saying then a miracle occurs to lead to this and the professor is saying I think you should work a little bit more on this part to explain why this is happening and that is why where we are with revitalization we think a miracle occurs but it We need to explain, we need to work more on how to improve the predictability of the outcomes in revitalization.

[01:01:12]We are working on it. One of the things we are doing in with my group is we are trying to improve the scaffolds. At the moment you just induce blood into the tooth. What we have done is proposed another novel way. What is that novel way?

[01:01:32]We have taken pulps out of extracted preolars for orthodontic reasons. So when preolars are taken out for orthodontic treatment, we immediately take the pulp out of the preolars and we desellularize them. What does that mean? We remove all DNA from these pups. So there is a system, a step-by-step method of removing DNA from the pulp. So we take this pulp, we desellularize it. And you can see here, this is a normal pulp. This is a desellularized pulp. There are no cells in it, which means there is no DNA in it. So it cannot provoke an antigenic response in the body. And the idea is to take these decelerized scaffolds and then to seed them with human dental pulp stem cells.

[01:02:31]So you take these decelerate scaffolds, seed them with dental pulp stem cells and we've already published this paper recently in international endoderontic journal and then you can reintroduce these pulps back into the root canal as a method of revitalization.

[01:02:50]Now we are at the early stages at the moment. There is lot more work to be done but this work is progressing.

[01:02:58]Finally revitalization procedures have shown promise but we still need to wait for long-term outcomes.

[01:03:07]Routine use for developmental anomalies is more evidence-based as compared to the use after traumatic injuries that have damaged herwig epithelial root sheath. And if you look at the guidelines that I wrote for the European Academy of Pediatric Dentistry, the European guidelines, they say very clearly you should consider using regenerative endodontic techniques in cases where root development is very incomplete.

[01:03:35]But use it with caution only in hopeless cases otherwise use MTA.

[01:03:46]But at the moment the evidence for revitalization is weak. But it is a technique which is available within dentistry and which will be refined more and more in the future with stem cells introduction with scaffolding introduction with introduction of signaling molecules. It's coming and by the time you guys graduate and go into your practices, it is highly likely that this will be a more established technique based on more scientific research. So you need to be well aware of it and Oh, we can't hear you. Doctor Ruff, >> can you hear me now?

[01:04:44]>> Yeah. Ah, >> so finally use conventional methods wherever you can. Use revitalization in a few selected cases. It's not mainstream yet, but when you do it, make sure you get informed consent from the patient. Tell them that it might or might not work. And that is very, very important. And with that I will stop.

[01:05:07]Thank you very much. I'll be happy to take some quick questions if you want me to take hold on I have disappeared.

[01:05:15]Uh Zoom is there. Yeah I'm back. There you go.

[01:05:19]>> Okay. So um we have a question about uh the uh uh I think you during the lecture you mentioned the use of saline solution and uh someone asked why uh 17% and not zero.9%.

[01:05:38]No, I I you are probably meaning hypocchlorite.

[01:05:42]>> Hypocchlorite. Okay.

[01:05:44]>> But we we only use we only use sterile saline.

[01:05:47]>> Okay.

[01:05:47]>> Because you know there is there is some evidence that if you use hypocchlorite you might damage the scap cells of the epical pillar.

[01:05:54]>> Okay.

[01:05:55]>> Okay.

[01:06:01]>> Okay. Uh are the another question is okay uh from your experience what are the most frequent technical or biological factors leading to early failure or revitalization in traumatizing uh incizers. Early what early >> uh an early fail failure for for the >> lots of reasons lots of reasons I mean most of the failures are associated with the root being so incompletely developed that you cannot do anything anyway but you know if you man if it the the problem is that if there is insufficient amount of root structure then almost nothing works but in those cases you can try revitalization and sometimes it works sometimes it doesn't work but it is worth trying revitalization at an early stage if the root development is so incomplete that you think there is nothing else you can do.

[01:07:05]>> Okay. said preparing for this lecture I've seen uh your perspective work uh about about this uh this topic and uh you reported uh the measurable s changes in the crown color crown and uh uh in practical term how do you advise the clinician to prevent and monitor these changes and how you explain to parents about these aesthetics risks basically >> yeah you you see Because revitalization is still not a well-established it.

[01:07:39]People are doing it a lot. But because it is still not 100% predictable, you must tell the parents that. Don't give the parents hope that this is some sort of a magic treatment. You must tell them that look, this is a treatment that has an unpredictable outcome. However, in your child's case, everything nothing else is going to work. So it's worth trying this particular approach but you must do it with absolutely with informed consent and with clear follow-up protocol. You should take radioraphs every six months to make sure that there is no deterioration around the apical area and just monitor it and if there is deterioration then the only other option at that time you will have is extraction in these cases cuz nothing else is going to work but informed consent and close monitoring is what you need.

[01:08:36]>> Okay. Um so in your view how should the uh recommendation you you have shown us uh the general pediatric dentistries chosen be between the techniques to use and uh how to apply them. So basically >> yeah you need to read those articles because in those articles we have reviewed all the evidence as well. So when you read you can see what is the evidence for what because you see when you make recommendations you have to make re and especially if you like this these are recommendations for whole of Europe that they're the European Academy guidelines recommendations have to be evidence-based so in these articles we have completely reviewed the evidence and our recommendations are based on what evidence is available in the literature.

[01:09:29]>> Okay. So our last question for today and thank you for your for your answers. Uh what do you see the future of the regenerative approaches in pediatric endodontics? Are we close to more predictable protocols or >> yeah we I'm not sure how close but the only way we can do it successfully is if we put signaling molecules into the root canal and give the right signals. If you imagine pulp is how many tissues in pulp you have odontoblasts, you have fibroblasts, you have collagen one, collagen 2, collagen 3, collagen 4, fibonctin, all these tissues have to be made and for each tissue there has to be a signaling molecule. For example, if you want to make blood vessels, you need vascular endothelial factor. You have to put it in the root canal. And now at the moment if you buy vascular endothelial factor one microgram is €12,000.

[01:10:35]So how will you do it? You can maybe do it on a very rich Russian oligarch possibly I don't know but nobody else will accept that right? Nobody else will accept a 12,000 one root canal molecule in the root canal. So unless in the future it becomes cheaper and we find ways of maybe isolating bone morph genetic proteins from the patients own blood and it will happen but it is not going to happen in the next 5 years. I can tell you >> it's a slow process but it it will happen. It will happen and the direction is clearly set that the whole medicine is moving into regenerative medicine and regenerative dentistry and it is inevitable that endodonics the only problem with endodontics is there are two problems one is which doctors don't face one is we are working in a very narrow confined space number one and number two the top opening is very narrow. So the apex is very narrow and then you have a very restricted space.

[01:11:47]So this is our limitation to make pulp within that small area with a little hole at the top. It's not going to be easy. How do you get blood vessels in there? It but eventually it will happen. Something will happen. It is five, seven, eight years but it will happen.

[01:12:08]>> Okay. Thank you so much. and um congratulation for your work and uh it's great to see uh researchers and professor with this great passion for the for the research work. So thank you so much for this insightful lecture and uh on the behalf on the organizing team uh I would like to thank you for uh contributing in this uh webinar session and uh for sharing your expertise with us today. Uh for me it has been truly a pleasure to have this talk with you and um I would also like to thank all all our participants and uh um reminding you to scan the QR code for the uh for the attendance today and see you uh in the next webinar of this session. Uh thank you so much uh professor Daga and see you to see you soon. Thank you.

[01:13:06]Bye.