From Blocks to Furnace: Unlocking Same-Day Zirconia Success

Every dentist gets those situations where it fits clinically acceptable, but there's areas that probably could fit better. And I immediately noticed zirconia kind of is a little bit more forgiving with fit. The fit to me has a big role in longevity, and that was one of the things that zirconia satisfied for me. Welcome to the Phil Klein Dental Podcast. Today's episode is packed with practical insights for anyone interested in same-day dentistry. Our guest, Dr. Mike Skramstad, takes us deep into the world of same-day delivery of zirconia crowns, a topic that combines digital workflow, material science, and the right technology in the operatory. He's a strong advocate for zirconia and will share his favorite new blocks on the market, explaining why they stand out in terms of strength, aesthetics, fit, and clinical reliability. We'll also discuss the advantages of zirconia in retentive preparations, where it can often be cemented conventionally, saving time and steps compared to adhesive dentistry. And beyond materials, Dr. Skramstad highlights why choosing the right furnace is critical, not only for speed, but for versatility across sintering, crystallization, and glazing. And finally, he'll walk us through his thought process on when to choose direct restorative options versus same-day indirect restorations. And for those of you who don't know Dr. Skramstad, he is a resident faculty member at Spear Education and Advanced Continuing Education Center in Scottsdale, Arizona. He also maintains a successful restorative practice in Orono, Minnesota, focusing on aesthetic, implant, and CAD CAM 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. Skramstad, thanks for joining us. Oh, thanks for having me. So dental ceramics like lithium disilicate and zirconia are getting a lot of attention these days. So to begin this episode, Dr. Skramstad, can you briefly sum up? why these materials are so significant in modern restorative dentistry? Well, I think the main reason they're significant is predictability. You know, when I first started using CAD CAM and CEREC back in 2002, we didn't have these materials. So we were kind of using, you know, trying to make weaker materials work. And then when Emacs came out in 2006, somewhere around that time, It really changed everything because now we had a material that we could literally put anywhere. It wasn't only an anterior tooth or a posterior tooth. It could go anywhere. So it really revolutionized and continues to revolutionize the dental market. It's aesthetic. It's fast to make in the office. And like I said, the most important thing is the predictability. We know it works. It lasts. It's strong. The bond is good. A lot of people still use that material to this day. I still use it every day. But I think where zirconia came along, you know, I first started testing zirconia in 2010. So it's not like it's a new thing. We've been using this for a while. The problem with the early zirconias is they were super strong. They fit very good, but it was the aesthetics. You couldn't really manufacture them in your office. You had to send out to labs. And they were very, very strong, but for lack of a better word, just kind of ugly. So it satisfied one segment of the market where you did the strength. An interesting thing that that proved, if you look at the statistics from a place like Glidewell, for instance, is when their first Bruxier came out, you know, the numbers skyrocketed, which kind of proved an interesting point that a lot of dentists were more interested in strength and predictability than they were with aesthetics. Now, where this started to change and we started to move it into the office was about 2016. And that was the first. time we were actually manufacturing zirconias in our office this is where the furnaces started to come into play where we could actually center these in a reasonable time to do a same day visit but the problem again back in 2016 for a few years was again aesthetics you know we just had these three wide very strong very opaque zirconias and you know now fast forward to 2025 we have the same predictability But the sintering speed is rapidly sped up and the aesthetics is, I would say, almost to the point of lithium disilicate at this point. They're beautiful restorations. And that's the 5Y component that's built into the gradient of the zirconia. Correct. Yeah, which was interesting because usually what they would say is, you know, the prettier the zirconia, the longer it took to center. And this is where the smart engineers that are smarter than me kind of figured out ways to make these work in a kind of speed-centering environment so we could have both strength and aesthetics. Yeah, and we're going to get into that, as you mentioned, the actual furnace itself, because taking six to eight hours to center something is not conducive to same-day delivery, obviously, and that's why they made these changes. So generally speaking, dental manufacturers, as they should, strive to design materials that deliver the kinds of things dentists are looking for, like any business. And that involves for dentists, long-term clinical success, patient satisfaction, and also very important is ease of use for the dentist, which includes efficient workflow. So let's talk about the zirconia block. When it comes to the zirconia block category, which is really a high strength oxide ceramic, dentists are expecting very high strength, like you said, that's a priority. We need to get that aesthetics up to par. And then we need that workflow efficiency, especially with all the digital stuff that's involved in this whole cycle of fabricating chair side. So are we at a point in our profession, do you think, where we have a zirconia block available to us that can achieve all of this and is capable of same day delivery for those that want to do this? of chairside milled zirconia restorations. Yeah, definitely. There's a couple of them out there that actually fit that category. But, you know, to back up, you know, with all these attributes of zirconia, what really convinced me was really two things. You know, honestly, with the lithium disilicate working so well for all those years, it was going to take quite a bit for me to change. And not that I've changed completely, but to kind of integrate it into my workflow. And I would say the two things that really convinced me were fit, you know, the zirconia block, the fit, it's just better. And the reason it's better is just because you're milling something larger with smaller instruments, and then you can actually center it down to a correct size. So one thing that I've noticed over the years of using CEREC and using digital dentistry and ceramics is, you know, every dentist gets those situations where it fits clinically acceptable, but there's areas that probably could fit better. And I immediately noticed zirconia kind of is a little bit more forgiving with fit. The fit, to me, has a big role in longevity. And that was one of the things that zirconia satisfied for me. The second thing, honestly, was as great as these glass ceramics are, you still have to bond them. And even for me, who's been bonding for years and years and years, the fact that you can cement zirconia. I think might be the number one attribute of the material itself is because dentists, you know, it just takes an aspect out of the procedure and the workflow that's difficult, right? It's an easy thing. It's stress-free. You can cement it and you can trust it. So those two things really kind of convinced me that zirconia was potentially the material. And then once the research started to catch up a little bit that was proving to us that it wasn't wearing the opposing dentition if it's polished enough, that it actually was clinically working and kind of dispelling. some of the myths that have been around forever was really helpful. But as far as actual clinical workflow, it really, you know, it was really the same workflow that we've been using before. You know, the missing piece, you know, if we were doing Emacs, you know, you image it, you design it, you can mill it in office, you can crystallize it in your furnace that we've had for years. So the only real difference was with zirconia is we needed a material that was going to look good. We have that. We have a couple of blocks that look good. We needed a material that was going to center fast. So I wasn't going to use a material that was going to take me twice as long for a similar result. So it had to be kind of on the same level of efficiency as the other blocks, which now with the new furnaces, we've achieved that. So I think the workflow is basically the same. We just have the blocks now. that kind of fit into our workflow so we can do these wonderful zirconia restorations in the same amount of time as we could do glass ceramics. Now, you mentioned something about cementation of zirconia. Are you talking about looting the restoration in and not using adhesive dentistry? Correct. Yeah. So for a lot of dentists out there, that's kind of a preferable way. You know, the adhesive dentistry, the isolation, you know, packing cord, using rubber dam, you know, well, that is great dentistry. It doesn't really, you know, I think that part of the success of zirconia is that aspect of it, is you can use a glass ion or cement, kind of like when you used to cement PFMs. And it works actually quite well, which I think is really, really desirable to a lot of dentists out there. What about non-retentive preps? like veneers? My general rule of thumb is if I will cement conventionally or loot with a resin out of a glass iron or if I have traditional resistance and retention form. You know, when I started getting into veneers or non-retentive onlays, if I do zirconia in those types of preparations, I will adhesively bond them still. I don't trust the, you know, it may work. I've never tried it. to be quite honest. But I go back to adhesive dentistry when I have non-retentive preps. Yeah, a friend of mine went to his dentist and wanted some veneers. And he asked me what material that is really strong. And I mentioned zirconia. And when he suggested having veneers made out of zirconia to his dentist, his dentist said, I don't use zirconia. I can't bond to it. So he's strictly an empress person. And I think this is where the education has to get out to dentists because there's so much research out there that dispels these rumors that you can bond to this quite well. I've had to remove some before and just going through that experience will prove to you that you can bond to zirconia quite well. Yeah, it was surprising to me because this dentist went to Coise's program, went to Spears program where you teach and some of the other top. notch programs. And he was not convinced that you can bond to Zirconia, didn't want to get involved with it. No matter how good the educator is, you know, it still takes time to catch up on the literature. And I can only speak from Spear's perspective, but the educators at Spear, you know, we completely believe in the adhesive capabilities of bonding to Zirconia, whereas in the past, you know, maybe not so much. Yeah, and I went to the Spear facility in Scottsdale, Arizona. It was very, very nice. Is that their headquarters there? Yes, that's where we teach. Yeah, and we did a live podcast there, and it was really, really interesting to see. They have a beautiful auditorium, great facility, so anybody interested in getting some advanced education, look into Spear for sure. So before we get into the furnace, let's get back to the blocks again. Could you recommend some blocks? typically happens after I do these podcasts is we get hundreds of emails and they say that was a great podcast. Dr. Skramstad was fantastic, but I still don't know which block I should start looking into buying. So from the standpoint of giving some choices to our listeners. So they don't send emails screaming for information. Could you throw a few out there? Or if you don't feel comfortable, you know, don't. But if you, it's up to you. Yeah, I think that the two main ones out there that I use in my office would be the Katana block made by Karari. That's a very nice one that you can center quite quickly and is aesthetic. And then it would be the Ivoclar Zerkad Prime block. You know, they're similar in the sense that they're both beautiful blocks and they both have high strength. I would say the fundamental difference between the two blocks, which, you know, the listeners may be interested in, is just basically how they're composed. You know, they're both multi-layer blocks, but the katana, for instance, is just one level of strength. You know, when you talk about 3Y, 4Y, 5Y, it's just one level and it's just built-in gradients into that level. What makes the Zercad prime block from Ivoclar a little bit unique, and it's the only one on the market in block form that I know of, is the fact that they have different actually strengths, different strengths in the gradient. So they have like a cervical zone, for instance, that's going to be the strongest, which would be... a 3Y. And then when you move into the body, it gets a little bit more translucent and then it goes into 4Y. And then the incisal zone where you want the translucency, where you want the aesthetics is 5Y. So it's an interesting and quite, you know, amazing that they were actually able to figure this out. So it's different strengths and aesthetics and translucencies. all built into the same multicolored block. Where other ones, which would be the katana and dense flat has one that also works good, they're kind of the same composition with just multilayer colors built into that composition. So these blocks obviously are designed to be cut milled chair side, right, for same day delivery. Now you need a furnace that could center these things. in 15 or 20 minutes. So tell us about the advancements in the furnace itself. And I know the Zerkat Prime Block by Ivoclor, I think the full name of it is IPS-EMAC Zerkat Prime Block. It's too many words to talk on a person. It's too many words. Let's just call it a Zerkat Prime. They have their own furnace, which is a very high-end furnace, very high-speed furnace. And it is versatile. I think it's called Programat CS6. So tell us about the advancements in the furnace. You could use that as an example, how it works with the block. And can we still do, you know, typical glazing of ceramics and crystallization of the lithium disilicate? blocks that we used in the past and still continue to use. Yeah, I think you used a key word there when I would describe the CS6 from Iverclar. It's versatility, right? So as a dentist, you know, I'm not always going to use zirconia. I'm going to want to mix in some other materials, whether that's M-Press or Emacs or whatever the material you want. So ideally, I'd like to have a furnace that can do all of it, right? um you know these furnaces are not cheap and in the in the past i would have one furnace for glass ceramics one furnace for glazing things and then another furnace that like you said took six to eight hours to just do zirconia so for the average dentist you know you run into problems of expense and you run into problems of room you know where am i going to put all this stuff so the advantage of the cs6 is is that it can do all of it in one furnace you know because many dentists are going to use different materials for different clinical scenarios so i think that that's the reason i think i really like that that furnace is because it can do zirconia like the the zircad prime block and you can do it very very quickly in about 15 minutes which is incredible for a sintering speed but then you can turn around on the next patient and you can crystallize an emax in 11 minutes which is the fastest crystallization of emax on the market you know so and then it's programmable like if you have a different material or a different glaze you can always enter that. So there's some openness to that furnace that some other ones don't have that are beneficial. So I love that it can do all the things I need it to do well, and it's versatile so I can do different materials with one furnace. And I do want to ask you this before we go on to the next question. I want to ask you about hybrid resin ceramic blocks. You know, the big push on that on the marketing side continues to be no sintering required. And these blocks are milled. And I guess they're just polished with some regular polishing tools and then they're put in the mouth, right? So you save all that time of centering. But what are we losing? I mean, we have to be sacrificing some serious strength here, are we not? Yeah, I think, you know, I have used those over the years and I still, I actually used one yesterday, to be honest. You know, so there are clinical scenarios where those come in handy. You know, when I look at things like crowns, you know, just a basic procedure like crowns, you know, those materials in some countries in Europe, especially Japan, for instance, they're used quite a bit. And a lot of that has to do with insurance reimbursements and things like that. But in the U.S., you know, if I have an option of doing a crown, I'm going to use probably a better material that's going to give me a better long-term success. I don't have as many worries of material itself breaking. Those blocks are very resilient, but they just don't retain their polish and sheen and they stain a lot. Where they come in handy, quite honestly, would be as if you have, if a patient can't do a crown, for instance, or you need to stage something, you're just going to do a large indirect restoration that would typically be like an MOD or something like that. Then, you know, it gets a little tricky to do that direct for me, at least. And so sometimes I can just, if I can just image that and mill that indirectly. charge the patient maybe a more reasonable lower fee for that surface and save myself a little bit of a headache, that is when I use it. When I used it yesterday, it was just a huge endo access that had a ton of decander crown. And I actually used it for a buildup because the patient wasn't ready for a crown quite yet. So it was kind of a three-quarter crown type. situation where i looked at that and i'm like you know to build this up in composite or build up material i'm just basically going to put a hunk of material on there then i'm going to take a burr and grind it all back or i could just image this and design something perfect and just bond it into place and those blocks only take you know four or five minutes to mill so those are the places that i'm using it personally is just for indirect restorations where the direct restoration may be unpredictable. Now, it sounds like to me your workflow is so dialed in and you have so much experience with chairside milling. You use that tool for just about anything you need. I mean, I never heard of doing a buildup with it as an endonist. It's crazy because I did a lot of buildups when I practiced endo. But that's really cool that you look at this milling, this chairside milling setup as a solution. to different types of applications that you need based on not only the fact that you can mill it right there, but you also have a variety of materials that you could mill from, which is a really great understanding of the whole concept. And I assume if you look back at all the restorations that you're doing, you're probably doing a lot less direct restorative because of it. You know, not always. It just depends on the scenario. You know, if it's, you know, because you have to understand that if you're going to do, let's just say an MO, for instance, an MO resin, is that you still need to reduce the tooth enough to be able to fit an indirect restoration in there. And quite honestly, sometimes you come down to the scenario of like, is it worth over reducing the tooth just so I can do it digitally versus if I can prep it very conservatively, like a slot preparation, for instance. and do it direct. So I would still say personally I find myself doing more direct resins than I do indirect resins in the milling. But then when you run into those scenarios where it's a gigantic restoration and I have to get out all these different bands and wedges and be inventive, and then it's still disappointing my result, then those are the scenarios where I would consider using indirect and mill it. Yeah, you just leave yourself a lot of options when you have that digital workflow down, Pat, like you do. So let's talk about digital workflow a little bit more. It's becoming more central to the complex cases. What are some key strategies that you could recommend to our listeners for optimizing these workflows without compromising precision and without compromising patient outcomes? Yeah, I think with any technology, you know, there's a little bit of a learning curve involved with it. I think the great thing is that the learning curve with a material like zirconia, for instance. is much less because the material is so much more forgiving. So my biggest advice for anybody just starting in digital that wants to get really, really good at it is basically down to the most simple level. You have to prep better, right? It all comes down to your preparation always. And whenever I get a result that maybe is a little suboptimal in my eyes, it's usually traced back to the preparation. So when I teach people that are getting into this, I tell them that You're going to naturally get better at preparing a tooth when you scan because you're going to see these preparations blown up and you're going to see that, you know, at 20 times magnification, you may not be as good as you think that you are. But those are the things. If you prep good, you're going to be very, very good at doing something like CEREC. If you prep poorly, you're going to be very, very bad at doing something like CEREC. It's as simple as that. The workflow can be learned. These workflows are getting so good. These companies are starting to introduce AI into their designs. And so pretty soon, it's just going to be you scan, you click a button, you get a proposal that's perfect, and then you mill it. And it's going to be pretty much all automated. But the one part still that's not automated that needs to be good is the prep. You know, when we first saw chairside milling, we saw a lot of adoption. A lot of dentists were coming in. You always have that group that comes in early. They get all the training and they can't wait to buy all the gadgets and start doing it. And then it tapers off a little bit. Now, with the new dentists coming out and dentists that have maybe been out five years, in the back of their mind, they're hearing about 3D printing where even zirconia. like in Europe, is being printed in the office or in labs. Do you think we've hit a point where the idea or the notion of 3D printing will become advanced enough where it could reach similar strengths as what we're getting on the milling side and with the sintering? Is that going to slow down the adoption of chairside milling? And are we at the point where this transition is beginning to take place? I would say we're getting to the point where you're starting to see the transition. And what I mean by that is, do I think it's ready? No. Is it going to replace zirconia right now? No. But what we're starting to see is the biggest roadblock for a new dentist or dentists out within five years, like you said, is just simply going to be cost. Getting into all this equipment after they have all these student loans and they're buying a practice, it's very restrictive. So I think you're seeing, you know, if I take that new dentist, but they want to get into digital, we're seeing a lot more of adoption of scanners and printers as opposed to scanners and mills. You know, it allows them to kind of dip their toe in a little bit to get into digital. They get the scanner. They can still send, you know, the more comprehensive things to the labs. And then they can start printing, you know, some things in their office, you know, whether it's a model, a splint, a surgical guide. We're seeing companies now printing hybrid ceramics, which is kind of like a resin ceramic material that's starting to get some traction. So I think that you're starting to see that as the first step, and that's being adopted a little bit quicker than milling, just simply because of cost. Now, is the quality the same? In my opinion, no, not yet. Now, will it be the same? Probably. You mentioned printing zirconia. We're not there yet. I think printing has some certain advantages over milling. It's definitely more precise. You don't have the burrs of the milling unit kind of going into the ceramics and creating room based on your prep. It's much more exact. The printers are getting faster. The workflows are getting better. So I think we're at a stage now where you're starting to see that movement a little bit into printing. And in the future, could it replace milling? You know, we'll see. I think that also you're seeing companies develop strategies to make the full workflow, like a CEREC workflow, is going to probably be a little bit less costly moving forward because they're probably seeing that. the same thing that you mentioned that we're seeing the writing on the walls, that adoption is not as quick and it's probably because of cost. So when you teach at Spear, are you primarily teaching milling or do you have courses on just adopting the scanner and then using a printer for some of the things you talked about and then using or communicating with the lab for those that don't have milling machines? Or is it strictly for those that have a CEREC milling machine at Spear? Well, Spear is divided into two separate kind of sub-companies. We have the Spear, the traditional parent company, and then we have a company called C-Docs. Now, C-Docs is a company that I worked for for 15 years. And C-Docs is traditionally just simply teaching CEREC, teaching workflows around designing and milling. Where on Spear, where I work now, in 2023, I transitioned from C-Docs into Spear. we're much more like kind of open-ended, so to speak. So we're teaching dentists. Some of them have milling units, but most of them are probably just scanning. So we're teaching them workflows on different scanners. We're not only teaching CEREC, we're teaching all the scanners. Workflows on how to send to the lab, workflows on how to 3D print. So where CDOX only teaches CEREC, SPEAR teaches pretty much across the board any digital workflow that's out there. Teaching, I think you could agree with me. enlightens the teacher sometimes as much as the student because the feedback you get from your attendees brings all new things into your mind saying, yeah, that's a good point. And you're constantly evolving into a really good educator that fits the needs of your students. I found that when I taught endo at Penn, part of our post-doctorate work was to stay in the clinic. and teach the dental students, you know, root canal. And I found myself a better endodontist when I was teaching. Is that you're finding the same thing pretty much? Yeah, you know, there's always scenarios where somebody will ask a question and the question will be so good that you as an educator will be like, I never actually thought of that. That's a really, really good idea. You know, that, you know, and I'm going to take that. Thank you. Yeah, no, totally. So yeah, so it's just all, you know, teaching brings about questions, questions sometimes that you never thought of or help create answers or create solutions out of a box that you haven't thought of yet. So yeah, it's... continuously enlightening, and I enjoy it very much. Yeah. Again, thank you for your contributions to Viva Learning. We really appreciate your time, and have a very good evening. Thank you. All right. Thank you so much for having me.