Beyond the Black Stain: Arresting Caries and Re-mineralizing Dentin

So we know that if we can place the silver fluoride a couple of times, we're going to have better arrest. But if we're not going to see that patient back again, that better arrest is out the window. And it depends upon the cavitation too, right? Is this cavitation a problem for the patient for us to leave it for another week? Are we going to get that patient back in another week? Are they going to disappear on us? Welcome to the Phil Klein Dental Podcast. So let me start this episode with a question to all of you listening. What is the most powerful, minimally invasive tool in caries management? I'll give you a few seconds. Okay, time is up. For those of you who answered SDF, silver diamond fluoride, congratulations, you are correct. In this episode, we'll explore the clinical applications of SDF, including single and multi-visit protocols, and how to determine the most effective treatment approach based on the patient's age and cooperation level. We'll talk about what kind of materials we should be using to restore teeth following STF treatment and how to manage the characteristic black staining that comes with its use. So if you're looking to enhance your toolkit for treating caries, especially in pediatric, geriatric, or high-risk populations, Stay tuned for a very informative conversation with Dr. Carla Cohn, who knows a lot about this topic. She's a general dentist devoted solely to the practice of dentistry for children. She owns and operates Kids Sleep Dentistry Winnipeg, a private practice at Western Surgery Center in Canada. Dr. Cohn is the founder of Lit Smile Academy, a CE company that organizes live, hands-on programs that focus on practical clinical dentistry. Before we bring in our guest, I do want to say that if you're enjoying these episodes and want to support the show, please follow us on Apple Podcasts or Spotify. You'll be the first to know about our new releases and our entire production team will really appreciate it. Dr. Cohn, it's a pleasure to have you back on the show. Why, thank you. And it's a pleasure to be here. Yeah, you're becoming a regular contributor on Viva Learning on the podcast program. And I know you're doing webinars. You've been doing that for a long time, but the podcasts are getting really popular and you seem to be quite a frequent contributor. So we appreciate that. Well, thank you. Frequent flyer. You're a frequent flyer. So today we're going to focus on the management of caries, both in children and adults. Let's begin with children. And one of the options which is becoming more and more popular as the research comes out is silver diamine fluoride. The upside is huge. It's showing incredible results as far as arresting carries. So give us your take on it. You've been treating kids for a while now, and we'd really like to hear your opinion on where we are with silver diamine fluoride. Yeah, so silver diamine fluoride is incredibly effective. Like everything that we do, it's not 100%. And we always strive for that magic bullet. We haven't quite got that magic bullet yet in dentistry. But silver diamine fluoride, when it came to the North American dental... professional community has been a fantastic tool and quickly became something, especially in pediatric dentistry, but also in geriatric dentistry that we kind of wonder like, what did we do before this came along? It's easy to apply. It is fast. It's inexpensive. It's effective. Nothing we do is 100%. How we put it on, how frequently we put it on. The type of lesion that we're putting it on will all tell us what the efficacy is going to be. But in terms of arresting caries, it's the best thing that's come along. I don't want to say ever, but it's the best thing that's come along in certainly any time that I can remember. And the key thing is here, Dr. Cohn, correct me if I'm wrong. You know, typically we learn in dental school to remove all the decay and we take this. hand instrument and we peel off, you know, what we call the leathery dentin. We really want to leave that leathery dentin alone and just take the mush off, right? Because the leathery dentin is totally remineralizable, right? Yeah, yeah. Tell us about that. How careful we have to be to leave that dent in there that actually we want to remineralize. Yeah. I mean, I've said this before a bunch of times and I've probably said it before to you. We have two things that we don't know how to do. We don't know when to start drilling and we don't know when to stop drilling. And the secret to success is to leave behind the affected dentin and take away the infected dentin. So how do you know when to stop doing that? And Carrie's dye detectors have been around forever and other things. But as our... profession and our materials evolve and get better. We have better materials that will allow us to be more minimally invasive, which is really what silver diamine fluoride is doing. And if we can get to the point of accurately diagnosing, accurately placing it on, effectively placing it on, maybe there's going to be a time in our, maybe in our lifetime where we don't have to drill anymore. It certainly is leading to that with SDF. Now, one of the things that I hear is a tremendous advantage to SDF is by leaving that leathery dentin alone, you're doing basically minimal intervention with the tooth, minimally invasive dentistry, as they call it. And you're minimizing the chance of an endodontic complication, right? Because if you're going to be peeling, yeah, you're peeling off that leathery dent and eventually you're going to end up in the pulp. In your experience as a dentist who treats primarily pediatric patients for decades, do you feel that since you've been using SDF, you've reduced endodontic involvement and thus reduced your endodontic procedures on these kids? Yeah. So when I'm using SDF, I'm using it kind of in two different ways. We use SDF for our pediatric patients when they're not cooperative. So we're using it as caries arrest when we can't get in there with... local anesthetic in a drill. And SDF has been this fantastic tool to be able to treat these patients at the very least to be able to delay treatment until they're older and more cooperative. The second side of that coin for the use of SDF is to use it to avoid a pulp exposure. So if we've got a tooth that's got deep caries, and we know that if we keep going for it, we're going to have an exposure. If we put the silver fluoride and we can arrest that caries and create some remineralization, then that's the second benefit to silver diamine fluoride. And they really go hand in hand because that kid that you've got that's uncooperative, if you've got the silver fluoride that you can put on there and you're arresting the caries, it's also not going into the pulp. So I use my silver fluoride in two different ways. But if you're anticipating an endodontic exposure because the decay is not leathery, but it is actually completely infected dentin, you're not going to put the STF on that. You'll go with the pulpotomy. Right. Well, so this is where it gets that line of diagnosis. You know, I'm putting the silver fluoride on, but I don't want to have communication with the pulp. Silver fluoride does not play well with pulp. So if I think that there is going to be communication, if that silver fluoride is going to keep penetrating and hit the pulp, then I'm not using the silver fluoride. Then I'm doing a pulpotomy, an indirect pulp cap with a medicament like a calcium silicate or a resin modified calcium silicate that is going to be able to help to remineralize rather than the silver fluoride. You got to be careful not to have the silver fluoride touch the pulp. That's not always possible to tell either. What's the main thing you go by? Is it something you do clinically? You're using tactile sense on that dentin and saying, this is mush. I got to go further. If I hit the pulp, I hit the pulp. Or is it a combination of that and radiographic examination? It's a combination of clinical diagnosis, radiographic diagnosis, and the historical diagnosis. So I'm looking to see, you know, not far from like on the tails of when I was doing my webinars for you and more podcasts on pulpal therapy. You take all of these things into consideration. What are the symptoms of the patient? What's the clinical diagnosis? What's the radiographic diagnosis? And a lot of times too, when we're using silver fluoride, we don't have radiographs of that patient because we're using it on that young, uncooperative kid that can't sit still for radiographs either. Yeah. So when it comes to restoring the... tooth on top of the SDF. I talked to some dentists and they're adamant about using glass ionomer. You know, they don't want to use composite. Now, I've talked to you before and even before this podcast episode, and you are a proponent of using both. Now that you're doing most of your work in the ER, not the ER, I'm sorry, the surgical center, the OR. Let's get our vowels correct here. That's all good. Yeah. So you're in the OR with your surgery center, which is a whole nother story, which is fabulous. You have more control over that site, right? So there's not a moisture tolerance issue as if there would be. and you're trying to get them calm in the chair in a busy practice. So talk about the use of glass ionomer versus composite resin as a restorative material over SDF. Yeah. So without question, glass ionomer on top of silver fluoride is a great marriage. you've got great, great adhesion of the glass ionomer. If you've got a kid that you can't keep dry, glass ionomer is the material of choice. And to put that over SDF is going to provide some masking out of the dark lesion, et cetera, et cetera. The downside to glass ionomer, well, there's two downsides. So the downside is it's not a very strong material and things have gotten better in the glass ionomer strength world. So if we've got a broad lesion, it's not going to hold up strength-wise. The other downside to glass ionomer, and believe me, after teaching for 15 years and talking glass ionomer and teaching glass ionomer, I know in North America that glass ionomer is not something that most of our dental professionals are comfortable or confident working with. And so we love composite resin. We have this great love affair with composite resin. We love to put it on everything. We love to build things and make everything look pretty. got the ability to keep this kid dry and i say kid but it could be an adult too you know we could use this on our on our adults and we still have the issue of masking out that dark stain you want to use a composite resin then we need to have something that's got some sort of blocker to it that is going to block out the the darkness because we don't want to have great teeth. We want our teeth to be aesthetic. For the dentist that doesn't work in the surgery center like you do, for the dentist that is in the typical dental office chair, and they can get control of the patient enough where they could use a composite, tell us what you do right after you put the SDF on. Do you wait for the SDF to work and bring the patient back and then do the restorative work? What's the process? And tell us about the composite material. So the process when replacing SDF is we're going to have an increased success if we can place it more than once. So ideally, we put the SDF on, we bring the patient back in again, we do a second application at least a week later, it can be later than that, and then restore it. There's all kinds of studies that are out there about biannual application, like indefinitely. Well, that's all good and fine if you can leave the cavitation. And sometimes we can leave that cavitation, but a lot of times we need to restore it. And so if we're going to restore it and we want to mask out the dark, and you're not wanting to use glass ionomer, then you're going to use a blocker and then a composite resin. So there's a blocker from Tokuyama, an omni-chroma blocker, and we place that on first, and then we place on the composite resin on top of it, and that's going to mask out some of the darkness depending upon how deep that lesion is, how close to it is to the occlusal surface or to the, you know, if you've got a soft, smooth surface on an anterior, how close it is to the buccal surface is going to depend on how you're masking out it. going to work how well you're masking out is going to work so the material has a blocker with it the composite or you buy that separately i you buy the blocker separately and you place the blocker on cure it and then carry on with your composite resin restoration so if you're doing a class one on a molar let's say um a primary molar and it's fairly deep but you got down to leathery dent and you decided i'm going to use sdf on that first appointment if you're planning to bring them back for a second application what do you use on top of that drop of sdf all the way to the occlusal you leave it nothing We leave it empty. But let me backtrack for one second. Yes, we leave it empty. And yes, there's still a cavitation. But what I do put on top of it when child or patient is in the clinic, because SDF is very metallic tasting. You put a layer of fluoride varnish over top of it, and then that does two things. It's going to kind of seal in your SDF so it can penetrate for the time period until the fluoride varnish rinses away or washes away. And then the other thing is it's going to help with the bad taste. So if that primary tooth has severe decay in it and you've removed all the decay and it's pretty bombed out, not too strong, it doesn't have a lot of support, you don't mind leaving it open? i don't mind leaving it open and you know you could do that other thing that you could do instead of um there's another procedure called a silver hall technique where we'll do the hall technique of the crown over top of the silver diamine fluoride so that's a possibility as well um but yeah the kid's gonna come in especially, you know, our non-cooperative kid, they're going to come in and we are going to just leave that cavitation open. They came to us with a cavitation, leave it open for another week. And then they come back and then we can restore it. You know, the other benefit too, and maybe we'll get to this, you know, I know we only have like half an hour and I've already been talking for probably 20 of those minutes. Not quite. 14 minutes so far. The other thing that happens is when I'm seeing these kids and it's, not just me that's seeing these kids in the in the operating room a lot of times you you'll see this child in your private practice your general dentist you're not comfortable or confident and seeing that they need to have the referral put the silver fluoride on them send them off to the specialist to do their their thing and then we get into this position so i get into this situation where now the kid is back in in my office or in the operating room they've got the silver fluoride on and here comes this question that We don't actually need to remove the silver diamine fluoride treated structure. We can just restore on top of it because it has effectively arrested the caries. So that's something that we need. to think about. And in terms of it's not just minimally invasive dentistry for the general dentist that's seeing this kid, but now it's minimally invasive dentistry for the specialist that gets that kid to restore them later on. And I think I digressed pretty badly off of where we were going. Yeah. And I think it's great that you brought that up, Dr. Cohn, about a GP who's planning to refer that patient to a pediatric dentist. They could place... stf in the tooth get the caries under control where where it gets arrested stopping the process so however long it takes for that patient to get to it to a specialist at least that decay is not getting worse and then of course you pointed out how important it is for the specialist to not touch that sacred remineralized area which is perfectly fine to restore a pond. That's the whole idea. So very, very good that you brought that up. And what's really interesting is that the research is showing that that silver has an extended effect, antimicrobial effect, which they call the zombie effect. I'm sure you've heard of that. Yeah. Yeah. So the zombie effect is that it's going to affect the teeth adjacent to it. And you're going to have these superpowers of the... The silver, yeah. The idea is obviously that the tooth itself is going to be resistant to infection because it's antimicrobial, the silver. Right, and the silver is antimicrobial too. And it goes back to the whole thing that we talk about with all of our materials now that have antibacterial properties. And there's tons of them out there that have the ability to release all of these calcium. fluoride, phosphate, borate, all of these ions. And it's great to have that as an ability. But I always say that if your house is burning, you're not putting wallpaper up in the bathroom. If nobody's brushing their teeth, we're going to have these materials that have the antibacterial. And how much can they actually do, right? Yeah. I mean, everything helps, but that's true. Yeah. And again, with the primary teeth, we're only looking for a shorter runway, right? We're trying to survive a shorter runway, which could be a year, could be eight years, right? It could go, you know, 10, 11 years if you've got a primary molar that's hanging out until that kid is 12 or 13. So it could be quite a long time and it is a shorter runway. And we do have much better idea at success. if we've got that primary tooth that's not going to hang around for that long. So again, you practice in an OR environment, which is obviously perfect for controlling moisture in the site where you want to restore the tooth. So you are a big fan of composite and you like the Omnichroma from Tokoyama and you also like the blocker. that is sold separately, actually, which is very effective in masking the darkness. Tell us what it is about Omnichroma that you think is efficient for these kinds of procedures and effective. So SDF in the treatment or even without SDF, the Omnichroma is unique in that it's Omnichromatic. And so one shade is going to match a whole range of shades for our practitioners from, you know, an A1, I think it is to a D4. And so if we've got SDF, the good part of this is that we've got the blocker and then we can block things, block out that darkness. But even regardless, if we're not using SDF at all, it's a great material because it's going to cut down on the stock that you have. And so you don't need to buy a whole bunch of shades. If we're doing pedo, you know, my shades are limited to probably A1 and A2, B1 and B2. But if I have a family practice, as most of our listeners do. you know, you're buying a whole bunch of shades that you're going to end up throwing out. They're going to expire with the Omnichroma. You don't have that problem at all. So let me ask you about anterior versus posterior with SDF. Posterior, you know, you're not going to get the pushback from the parents as much for the black staining. And again, it depends on the family, the kid, the parents. When it comes to anterior, tell us how you finesse that conversation. And what do you do restoratively at the time you place the SDF to kind of block that black stain? And when does that black stain occur? You know, how soon after you place it, that kind of thing. Fill us in on all that. Yeah, all great questions. And that's where we do get the pushback from, is from the parent on an anterior, because that's in the aesthetic zone. If I have parents that would have refused SDF, it would have most of the time, they're refusing it is because it's an anterior. So, you know, the whole conversation about what's best for your child comes into play. You know, can we arrest this caries and maybe let's not worry about some darkness. The darkness doesn't happen right away. So you can be in your practice, put your SDF on, you're rubbing it in for a minute, and then you're seeing that, oh, there's not a lot of color change. Oh, maybe we're okay. You're not okay. So time is going to go by, and as the silver begins to oxidize, you're going to see that darkness. So don't be fooled into thinking that it's not going to turn dark. It will turn dark. And and then, you know, if you're looking for an immediate mask out, the best thing for an immediate mask out after is still to put some glass ionomer. The moment that you hit some light to that freshly placed SDF, even if you think that you haven't gotten it on the margins, you're going to see it. So if you're doing something immediate, silver fluoride and then an immediate restoration over. then a pure glass ionomer is really the way to go. If we have the ability to let that sit and bring the kid back again, then we can consider our other options or other alternatives. Right. So in the case where you do restore it with a glass ionomer on the anterior, that masks out the inevitable black staining and then you do not have to bring the patient back to restore because it's done. Yeah, well, yes and no. Is it going to mask it out completely? Probably not. Are you going to need to bring them back? You definitely need to bring them back to re-evaluate. And with glass ionomer, if you're placing a pure glass ionomer, there's washout issues. So, you know, it's not your it's not your ideal situation in terms of you can't set it and forget it kind of thing. You're going to place it and you you got to you got to follow up and you're probably going to be back in there. And, you know, like you said earlier, there's the short runway that we have with these primary dentition. If you're doing an anterior for a kid, those centrals are out around the age of six. So, you know, how much time do we have? But also keep in mind. Right at that age of six, five, six, when these kids are going to school and they're making their social connections, it's a big deal to have teeth that are not black. So as we get into the bottom of the podcast, and I know you treat primarily kids. But for those dentists out there that are treating everyone, including children, and they want to use SDF more, tell us about how SDF is used in adults or young people that are not kids. Tell us the process there. Now they're going to be, we're talking about permanent teeth, and we're talking about probably more use of the omni-chroma, that type of composite. Yeah. So, you know, seeing these older... Patience is outside of my scope of practice, but the materials work exactly the same way, whether you're two years old or you're 22 years old or 102 years old. So in that situation where you're wanting to use it and arrest caries, yeah, absolutely. You've got the ability to keep the area dry and putting a composite resin in. much less of a challenge than on an uncooperative child. But we want to use our Omnichroma blocker and we want to use our Omnichroma to be able to restore aesthetically, regardless of whether you're a kid or whether you're an adult. It's a great option. And I know that our dentists out there that are confident and comfortable using composite resins, you're going to have far better success using something that you're comfortable and confident with than bringing in material that you're not comfortable with. And these are easy to use. It's within our tool house. Toolbox? Wheelhouse. Wheelhouse, that's it. Wheelhouse and toolbox. Yeah, okay, thank you. When I need your help, you're going to have to bail me out too. Absolutely. Anytime, anytime. So getting back to permanent teeth, you mentioned that in the primary tooth, you leave it with the cavitation. Patient came in with cavitation, you send them out. Meanwhile, the caries is going to be arrested. And when you continue with the second treatment, you can then worry about... either going with a type of product like Omni Chroma or going with a composite, a similar composite, whatever, or going with Gloss Atomer. But with the permanent tooth, you don't want to leave it with, an adult comes in and you remove all this decay, but you leave the leathery dentin, you treat it with STF. But I would assume in almost every case as an adult, you're going to want to restore that with a composite that day. So you have to make sure that that darkness is not going to seep through. Yeah, you just, you know, make sure that you've got a good layer of the Omnichroma, the blocker. So when I'm doing these, and I've restored a couple of silver fluoride with the Omnichroma blocker, and documented for an article that I wrote, and I would tell you the journal, but I can't remember the name of it right now. You want to put on a couple of layers of your Omnichroma blocker. That's your superpower is to use enough blocker to block out the darkness and then go ahead with your Omnichroma, the composite or the flowable or the composite, whichever. Right. And basically, you're saying that the effects of SDF, regardless of whether you restore that first treatment or leave it alone. will still be effective. You don't need to come back. Okay. So you don't need to come back and treat it a second time. Yeah. Yeah. And, you know, that's where we weigh our risk benefit, right? So we know that if we can place the silver fluoride a couple of times, we're going to have better arrest. But if we're not going to see that patient back again, that better arrest is out the window, right? So do we restore it? And it depends upon the cavitation too, right? Is this cavitation a problem for the patient for us to leave it for another week? Are we going to get that patient back in another week? Are they going to disappear on us? That all happens too, right? Absolutely. You know, the way we're describing SDF here in this podcast episode and backed up by all the evidence-based literature. SDF is really a magic liquid. You know, it does things that we were not able to do 10 years ago before they allowed it to be approved in the United States and North America. So my question to you is, why are dentists not using SDF on every patient where there's leathery dentin? I mean, I know in dental school, we were trained to peel it off and have squeaky clean. walls and the instructor would come by using our Explorer and scraping the walls. And if it doesn't squeak, you know, it's not clean. But those days are over. Why are we not adhering to the current protocol of taking advantage of such an amazing, minimally invasive material that is so effective in arresting caries and remineralizing dentin? Yeah. Yeah. You know what? It's a paradigm shift that we need to make. And and no pun intended. We've had it drilled into our heads that we need to keep things as as clean and, you know, nothing left behind. It takes time. It takes a lot of time for us as a community to change our thought process. And I would say just like keep looking at that evidence because we're seeing the evidence coming back more and more that this is incomplete caries removal, you know, with or without SDF is an advantage for our patients and it's an advantage for us. So, you know, keep at it and keep. keep ourselves true to what is out there in the evidence-based literature. So before we wrap it up, Dr. Cohn, tell us about your CE program. And I know you have a program in Mexico in November. Yeah, so my continuing education platform is Lit Smile Academy. Got a continuing education travel coming up in November 22nd, and that is to Mexico. So check that out, litsmileacademy.com or send me a message. I'm always happy to hear from everybody. Yeah, I've heard nothing but great, great feedback on your continuing education programs, your teaching and the colleagues that you have that teach with you. Fantastic stuff. Thank you so much. Thank you. My pleasure. Thank you for having me.