Bonding Breakthroughs: How Adhesive Innovations Are Transforming Dentistry

Minimally invasive dentistry, which is kind of an interesting thing, especially in the posterior relationship to preparations that make no sense at all, have no retention, but yet I'm getting great longevity out of these restorations, saving great amount of tooth structure. And from a public side, it's kind of interesting too that they're starting to get a little bit of a beat on, wow, you can do things differently. I don't need my tooth hogged down. Welcome to the Phil Klein Dental Podcast. All of us listening today are in some way or another enjoying the benefits of adhesive materials. Arguably, they have revolutionized modern dentistry, enhancing both the functionality and aesthetics of dental treatments. We all know this. And these innovations have expanded the possibilities for minimally invasive procedures, allowing us to preserve more natural tooth structure while delivering durable, long-lasting results. Today we'll be talking to Dr. Troy Schmedding, a dentist who has practiced general aesthetic dentistry for over three decades. He'll share with us how he's taking advantage of modern adhesive techniques, and he'll also tell us the adhesive products he continues to rely on for long-term clinical success. Dr. Schmedding is an assistant professor in the Department of Reconstructive Dental Sciences and co -course director for Integrated Preclinical Technique at University of Pacific Dentistry. He practices in Walnut Creek, California, and enjoys lecturing nationally and internationally to fellow colleagues on restorative and aesthetic dentistry. Dr. Schmedding, thanks for joining us today. Well, thanks. It's always nice to be here. Nice to see you again. Yeah, absolutely. So your practice is primarily focused on restorative aesthetic dentistry. For the most part, what kind of cases are you seeing and treating in your operatory? Well, you know, it's interesting. I mean, I'm a general practice and, you know, generally where I'll take will be different focuses in relationship to potentially some, you know, some orthodontic side, some endodontic side. But really, I've been true to just being a really focus based on restorative-based dentistry. And it's kind of interesting how that's evolved over the years in relationship. It's kind of fun when you think back to those days of coming out of dental school and, you know, what you were taught in comparison to being in for practice for 30 years now. just the vast difference in how I even approach a single preparation in relationship to a direct or an indirect, which has really been nice. It's been a nice... You know, a salvaging of tooth structure is kind of the way I feel about dentistry now. It's an opportunity to do things a lot different than I ever have before. And really what that does is lead me down that road of adhesive-based dentistry. And everything I do is adhesive-based. And I think most of your listeners out there would probably agree that they sit back and think about, wow, how much stuff do I bond today? How much stuff requires a light to be hardened and processed? And, you know, all those type of things. thing but my focus of my practice really is is really direct restoratives um and indirect in relationship to we do a lot of you know cosmetic cases Minimally invasive dentistry, which is kind of an interesting thing, especially in the posterior relationship to preparations that make no sense at all, have no retention. But yet I'm getting great longevity out of these restorations, saving great amount of tooth structure. And from a public side, it's kind of interesting too that they're starting to get a little bit of a beat on, wow, you can do things differently. I don't need my tooth hogged down. And things I hear from patients directly is that exact term. Well, I don't want my tooth hogged down. What can you do differently? So it's kind of a fun evolution. Yeah, let me ask you about that. So there's some different thought processes on that. So some are saying that dentists are relying too much on the adhesive. nature of the newer advanced materials. So these teeth that have more than half the distance of the tooth gone between cusps, there used to be a rule that Gordon Christensen said many years ago, John Coise was kind of promulgating one third of the tooth structure missing between cusps, it's time to put a crown on. Are we jeopardizing or risking the tooth to a fracture? by relying on the adhesive dentistry to hold these large restorative composites in there and not going with a full crown or at least coverage of the cusps? Yeah, I mean, I think that's a valid question. I mean, I think definitely do we push the boundaries more than we ever have before in terms of the use of a composite, for instance? And I think that'll show slightly in the data too, in terms of, you know, what are the failures in direct composite restorations? And it's generally secondary decay or fracture of restoration or tooth. And so whether that's a good thing or a bad thing, it's tough to say, really. I mean, because sometimes you're doing a service for a patient that may not be older for the coverage crown, that type of thing. But if we're going to look at it from a peer didactic type of research type situation, yeah. I mean, I think we probably do push it a little bit in certain situations. You know, how to minimize that and how to increase your longevity always comes down to basic principles, meaning go back to your early dental school days is evaluating the tooth structure, evaluating the occlusal contact point. And a lot of those type of things that are extremely important when you talk about minimally invasive dentistry, because, you know, at the end of the day, what generally wins is occlusion. And if we don't recognize occlusion and take care of it, I'm not sure it really matters if you're full coverage or minimally invasive. the options are still bound to some basic old dentistry. And I think that's still a great thing. But yeah, I think we do push the boundaries more than we ever have before. And is it a sense of a catastrophic type situation? Most of the time, not. So you're not seeing fractures on these teeth where you're doing heroic, and I'm using heroic in quotes, based on your adhesive materials that... in the past, we would have not even thought about doing a direct filling. We would go straight to indirect because we need that protection of the cusps. You're not seeing those teeth fracture when you're making those restorations quite large with the composite. Yeah, that's an interesting point. Yes, I think we are pushing things a lot farther in that sense that before I'd be like, oh, I don't have any options, right? I don't have the options to do much, so I'm going to put a crown on this. But yeah, what I do see is the bigger restorations or things that even come in that I didn't even do that have been there for long periods of time usually have a very good repairability rate. So, I mean, if we want to compare it to our... older days of amalgam and whatnot, you know, a lot of times, what did you find? You find a lot of catastrophic breaks, right? I mean, just kind of depending on how that would work. So do things break and do things fail? Oh, sure. Till the day we... So they were done with dentistry. But the bottom line is repairability is really what I see as terms of an added benefit of adhesive-based dentistry being more minimally invasive, giving you the opportunity for things if they do fracture or when they break or whatever may happen, you have still some remaining two structure that allow you to at least try for another effort of some sort. Right, as long as you don't get a fracture too low. Okay, so let's talk about the adhesive part of what you do in your practice. For you to be a successful, aesthetic restorative dentist, you need to rely on a strong, long-lasting bond. That's what adhesive is all about. And we talked about this offline. Dr. Schmedding, you employ the latest generation of bonding technology. It's from a company that we all know, Curari. Full name is Curari Nuritake. I think I pronounced that correctly. So that's a universal bonding agent that you're pretty fond of. So tell us why you use this. given that there are so many choices out there for dentists to choose from. Yeah, I mean, there is a lot of choices, no doubt about it. I mean, I think if I understand thing correctly, I think Henry Schein has over 200 bonding agents in their catalog. So, you know, what is that telling you? It's telling you a lot, to be absolutely honest with you, meaning I don't think Schein's going to carry a bunch of products they're not selling necessarily. So is there a dentist still using products from the early... 90s, late 80s. Yeah. And those are the total etch techniques. And to be honest with you, historically, if you want to look back at research and track the data, there's still some very good numbers about total etch programs. So yeah, I think those are relevant. And then we kind of moved on to a situation where I still use sixth generation, which is a self-etching product. Karari's SE Protect being kind of the... The gold standard in that department. And another great technique, right? It's been around for a long time and longevity is still there. But as we've evolved, we've kind of adapted this universal type situation. And yeah, I do use universal adhesives a lot in my practice. And I use universal bond quick. Universal bond quick too now as we have a predecessor to the... universal bond quick. But really why I use this product and what draws me to that is really the name Karari Noritake in the sense that they've been around for a long period of time. And there's a monomer that they created many moons ago called MDP. And this MDP monomer is really what's revolutionized bonding agents and this term universal. adhesives, basically. I mean, if you look back to about 2011, I think it was when they lost their patent on MDP, all of a sudden you had this massive flood of universal adhesives come to the market. And why was that? It's simply because they... manufacturers that knew about MDP for many moons before that patent ran out were ready to jump on that. So what that does is a creation of this monomer that gives you the ability to bond to everything in dentistry. I mean, in relationship to what we do, whether it be tube structure, whether it be ceramic, whether it be a non-glass-based ceramic, whatever it may be, it has an affinity for that material. And so with that said, Karari still, in my opinion, has the... has the lead in that department in relationship to research and things that go behind these products for a long period of time. So when they came out with a universal adhesive, yeah, I was one of the first to be on board because of that reputation and that research base that they have in relationship to prior products. And what I find is it's a tremendous asset to any practice. So given the fact that now, what is it, a one-step bonding? Versus multiple steps multiple bottles. So you're saving a lot of time and I know there was some controversy when these You know universal bonding agents came out originally In that the bond was not as strong, you know, it's like you're combining the primer and the bond into one system You're not going to get the same as what we what was the best generation of the past fourth generation. I don't remember Yeah, so fourth generation was your total etch system, two bottle system. And then your next best would be the sixth generation, which was a no etch, but rather a self etching technique. But I think you hit it on the head. I mean, I think you hit it on the head a lot with universal adhesives is that, yeah, some of the numbers early coming out weren't so great. Because why? I mean, you're combining a lot of different things in one bottle. And whenever you combine chemistry in one bottle, it definitely increases your complications. contrary to what you think, right? You put one bottle on the table, this has got to be a lot easier to use. Well, really, in the end, it's not. It requires a lot more... This technique requires you to have a system that you know and is predictable in relationship to application time, air thinning time, light curing time. And really that's another great thing about the Universal Bond Quick 2 is that they've really simplified the instructions with this material. So for instance, they have an application time of three seconds. There's no another one on the market of that application. Right. They said there's absolutely, what I've been reading about it is Universal Bond Quick 2 is that there's no wait time at all. almost immediate as far as ready to go. Yeah, and why is that important? I mean, simply because most dentists don't wait anyway, right? So they have a great universal adhesive they may be using, but they may have an application time of 10 to 15 seconds. And those are important. I mean, they don't just come up with these numbers for a reason. They actually have data and research behind these instructions. But most dentists, as we all know, we don't read instructions for one. We're not very good at that. And secondly, application time is probably two to three seconds anyway. So that's kind of what you said earlier, you know, when you talk about these. bottles of inventory. They're easier. They're simpler for the staff, but they're really not in terms of application to the tooth. You really got to know what you're doing. So I think that's another leg up for Universal Bond Quick 2 is just the ease of application that most of dentists fall into already. And it's just kind of a quick, easy transition. Yeah. And that's a big thing. Ease of use is a big thing. And the staff loves that as well. So there's been a change in the film thickness from Universal Bond Quick to the newer one, Universal Bond Quick 2. Correct me if I'm wrong, Dr. Schmedding, but it's almost half the film thickness. It's in that range in microns. I'm not sure of the number. What does that do for you? I mean, that's just not a claim. That's actually something that actually applies to clinical relevance and your life as a dentist, as a clinician, and the success of the case. Talk about that a little bit, just that difference in film thickness. Yeah, so film thickness, you know, for me, it really plays a lot in the indirect world. And I guess the scenario would be simply that when you're seating an indirect restoration, whether that be a ceramic posterior onlay or whether it be a veneer of some sort, yeah, you want great marginal adaptation. And so a lot of things that can go wrong when you're bonding in these areas are simply that you're not air thinning well enough. You're creating a pooling along the margins, creating what we would call a false margin, elevating that off the two slightly where you have a bigger margin based off resin rather than a close gap with ceramic. So really the film thickness part of that. Universal Bond Quick 2 is like a three to six micron film thickness, which I'm not sure if there's any one else in the market that that's thin. Bonquic predecessor was, I think, five to 10, somewhere in that area. So I think, yeah, you do get some thick... Film thickness decrease for sure. But for me, it really helps benefit in terms of seeding in my restorations, making sure I'm not pooling anywhere, getting to that point where I'm getting a better marginal seal than I would necessarily with a thicker material that maybe I didn't thin quite as well. So that's a real huge advantage for me in that particular aspect. So talk about the etching technique that you use prior to the spawning agent. How do you typically... etch the tooth. So interestingly enough, universal bond quick and most universal bonding agents, you can do any of the three steps that you want. I mean, you could do a self etch where you're simply not adding any phosphoric acid. You could do a total etch, just like a normal technique of the phosphoric acid. And those applications seem to work very, very well. For me, I've kind of gotten away from phosphoric acid or total etch technique. And that's just a personal opinion. I don't really have any relevance to say one's better than the other because the data is pretty mixed out there in terms of which is better than the other, so to speak. But I think the ability to use this functionally is nice because application of phosphoric acid, we're not all very predictable, not all phosphoric acid stay in place. And so a lot of times you are getting etch onto the dentin when you may have think you're not doing it, but you probably are more than likely. So universal adhesives will cover your... so to speak, a little bit on that. But for me, I'm an etcher of enamel only. I don't do any etching on the dentin portion of it. And I think, like I said, you can go predictably pretty well with either one of these at this point. So that's kind of a nice thing, right? I mean, not that you need to be sloppy with your dentistry, but ultimately, if you do get some phosphoric acid in different spots that you didn't mean to, not the end of the world. If you're a total etcher, yeah, the data is showing some really good long-term bond strengths either way. So functionality, I think, is what's a key takeaway. with these materials. So let's talk about the core buildup also, Dr. Schmedding. So often we have to do a core buildup. in the days when I practiced as an endodontist I was often either preparing the post space for these teeth that were fairly broken down after the endo was done and then sending the doctor the post or putting it in for him or her today we're not using as many posts obviously the adhesive materials are so advanced so talk to us about making sure that the core assuming you're not going to use a post or maybe you are How do we get the core to be so tightly adhered to the actual preparation? Yeah, I mean, that's a great question because we do see bond failures in relationship to core buildups. And so if we talk about the basics behind it, what's one of the most difficult things that you deal with when you're placing a post, for instance, which you're right, we don't place as many posts as we used to, but ultimately what do you do? And you're trying to place a bonding agent down a canal and you're trying to shine a light down there, right? So what's your predictability on that? Very, very little, right? In terms of getting a hundred percent polymerization. So a nice thing that comes with the universe. Bond Quick is they work with their own core base called DC Core. And one of the unique features of that is that you have built into the DC Core in combination with the Universal Bond Quick 2 is a self-care protocol. So meaning upon contact or polymerization of those two in coherence with the dual-care apparatus of that build-up material, you will get polymerization of the bonding agent as well. So in cases of bonding in a post, for instance, you can do a couple of things. go ahead and clean the canal space you can go ahead and etch it whatever your protocol is and then when you use the universal bond quick you're placing it down the canal air thinning it dramatically placing some dc core down the post or down the space, putting your post in there and you're allowing that to polymerize. So really the key to that is ultimately the polymerization that's happening in the dual cure process. So dual cure, obviously for me is a very big component when I can't get a light source to us. And it should be for all of us in the adhesive base world because your weak link can certainly be the light. Right. So you got to get some energy to it. So the combination of those two together has been a huge win in relationship to just making sure I'm getting that polymerization, getting the maximum properties out of these materials that for me, I very rarely have ever see a buildup come out. So how do you apply the universal bond quick to into the post space? How do you get that material in there? Just long micro brushes. I can't remember exactly which one I use, but there's some endo micro brushes that have real long tips on them that allow you to get way down the canal and clean those out really, really well. Right. So you coat the inside of the canal space. Yeah. The post space, I should say. And then it's almost immediate, right? You don't have to wait just like you don't have to wait when you do any other bonding outside of the canal. So within a couple of seconds. you coat the post if you're using a post with the what was the core material that you use that's part of that core it's called dc core okay yeah you coat that and do you inject the core material into the post space as well and then seat the post yeah I do. They have an application tip on their DC core that can get you down the canal just to get enough application down in there to apply a little bit, then seeding the cement to help push the material up and out of that canal. Then I'll do a block placement, continue placing that around the post all the way up to desired height. Nice material in the relationship too, no slumping, stays in place, all those types of things. You put the binding agent though on the actual tooth preparation that's outside of the post space. knowing that that core material is going to be injected all around correct so all that 100 all that bonding that whole two right so the whole two surfaces bonded plus the inside of the canal space and then you just create this monoblock type situation correct and you're good to go and that's all you're really relying on the self-curing you're not really even are you using the light even to try to get down the canal you could uh like cure that bonding agent prior to that. And then the dual care portion of that will scavenge any of the unpolymerized resin that's still down in the canal. But I generally don't, but you certainly could. Right. The core is done. And now we're ready to cement the indirect restoration that we've all been waiting for, right? So tell us what the clinical procedure is for cementation, knowing that you've already put down the universal bond quick too. For cementation of the... indirect restoration, yeah, I would have the patient come back and I don't do any milling in my office. So everything for me is a lab situation. So I'm still temporizing all those wonderful things that need to go along with that. But for me, when I get a patient back and take off that temporary, the first thing I'll try to do, especially if I have a very large core buildup in that, is I'm going to rejuvenate that. And there's a couple of ways I do that. And a majority of the time I use air abrasion. I'm a big fan of air abrasion, freshening the surface, cleaning off any of the debridement. The other thing that I'll use is a product by Karari also called Katana Cleaner, which is a very interesting cleaning agent. It can be used intraorally and extraorally as well in relationship to priming or cleaning of zirconia, Emax restoration, that type of thing. But it can be used in the mouth too. And it's based off the same MDP-based chemistry, but it has more of a soap type feature. So it creates a little bit of the soaping process that will help lift off any debris and clean the tube. structure. So I'll use that if I'm a little worried about bleeding or anything that I could cause potentially with using air abrasion. But most of the time I'll use air abrasion from that. standpoint of reinvigorating the composite, getting it ready to be bonded to. And then from there, the interesting thing is that Karari has a product that works directly with an indirect situation in terms of a Panavi SA Universal as their new self-adhesive bonding cement out there. And the beautiful thing about that is it works very similar to the DC Core in relationship to UBQ2. So if I am going to do a bonding situation where I have a minimally invasive, lack of retentive type preparation, I'll clear the tooth. I'll do any type of etching. And for me, the etching is going to be on the enamel. So if I have enamel surface, I will always etch the enamel. That's just kind of a protocol I live by in terms of etching enamel, getting that ready in terms of increasing the micromechanical side of enamel. Then I'll apply my universal bond quick too, just like I did for the post space. But for this, I will do the exact same thing. Apply it. air thin it. And then Panavia SA Universal will be directly incorporated into the restoration and then seeded. From that point on, I'm going to do a little tack here to help kind of clean up the perimeter side of it, the outside. But then I'm going to let that polymerize for a good three to five minutes in a self-care effect, doing the exact same thing that the post was doing, but allowing it to go through its photo processing and do all those types of things. And then from there, I will tack the margins again once we're all done just to make sure, because there's still some camphorquinone in these materials that are light sensitive. So I like to take it a little bit over the top. But once again, it's that ability to use a bonding agent to increase my bond strengths and my restoration, but also use it in the sense that I don't have to light cure it, allow it to do the self-cure, which is inherently built in the Curare program, and then allow that to work that particular way as well. So you don't even light cure the Universal Bond Quick 2 before you do your cementation, and then... it to also self-cure on top of that you just go straight to self-cure correct straight to self-cure no light curing wow that's nope haven't done it for about three years and i have not had a restoration come off knock on wood i'll probably get a phone call right now but well i mean i mean it makes total sense i mean if it's going to fully cure eventually it may take a little bit longer if you don't like cure but it doesn't matter because that crown shouldn't come off unless it's completely relying on adhesive and there's no retention then maybe You know, there's a risk that if you don't like your, I don't know. How long does it take for the self-curing properties to take effect where you get the same kind of retention as if you light cure it and then seeded the crown? It's about three to five minutes generally somewhere in there. I guess there's no real reason to light cure it then in that situation. Not necessarily in my opinion. Just out of curiosity, zirconia. There's a lot of controversy about whether or not you can actually bond to zirconia. And a lot of people are still using Emacs and so forth. You have no problem with bonding to zirconia. What's your take on that? Yeah, I have no problem bonding with zirconia, and I can definitely feel very comfortable. I mean, even research-based-wise, at this point in time, there is clear clinical evidence that you can bond to zirconia. I think it's kind of one of those situations where you just need a little bit of education on it because it's not a complicated thing. It really comes about cleaning your zirconia, priming your zirconia, and using the correct cements on those. And I've had zirconia veneers in the mouth for seven years now. I mean, so non-retentive zirconia. And everything I do in the posterior is a non-retentive way too. So I do lots of zirconia. Is Emax a great material? 100%. Absolutely. Do I think there's a clear winner in terms of material? No, I think they both have proper places. And I think they're both a wonderful addition to what we get to do in dentistry. One last thought before we wrap up this podcast, Dr. Schmedding. It sounds like to me... You seem to like to stay within the same system of a company using their bonding agent, their core material. You feel more comfortable staying within the same company's product line when it comes to the adhesive products and restorative composites and so forth? You know, I do. I really, at this point, I really do. And I think just taking a look at universal adhesives, like we talked about earlier, there's a thing that we didn't even mention today, but there's dual care activators that a lot of these come with. And you may find them in your kits. And the reason they're in there is because you'll have to use those sometimes when you're using dual care products like we talked about in relationship to core buildups, cementation, even composite restoratives. where you'll have that situation where your compatibility issues go down. And so your core materials can pop out and you may even see that, right? You do a nice core buildup and you went and prepped it and it fell out, right? Different reasons. So inherently, some of the companies aren't cross-linked well with other companies at this point, especially in terms of the single bottle adhesive system. So yeah, do I think it's a little bit or a lot easier in many cases? I really do. Do I think it's a problem in just direct research? in relationship to just layering composites. No, I don't think that's a problem. I think it really comes down to what we talked about earlier, dual cure compatibilities and not knowing that you have to use dual cure activators to make these materials work better for you. So there is a few things because marketing wise, it's never really cool to sell a single bottle. He said, but hey, you got to bring his cousin along with if you want to really work well. So anyway, a few things to think about on that, but I do like staying within family tree, especially. on the Dual Cure product platform. Excellent. Excellent insight, Dr. Schmedding, as usual. I've interviewed you many times before. You're great to talk to. So much experience, 30 years of clinical practice and keeping up with the newest and advanced materials. So we're very happy to have you share that with our audience. Have a great evening and thank you very, very much. Thanks so much. Always great seeing you.