JAN 5TH 2024.docx

SPEAKER 0 But we might as well start really quickly with a little overview of where we've been and where we're going. Why not? And for anyone who still arrives in the next few minutes, they didn't miss anything really important. So you're familiar with what we did last semester was primarily preppin...

SPEAKER 0 But we might as well start really quickly with a little overview of where we've been and where we're going. Why not? And for anyone who still arrives in the next few minutes, they didn't miss anything really important. So you're familiar with what we did last semester was primarily prepping and temping, as we had talked about. It's in the schedule. This isn't working. So how do we make this louder? I can hold it here. Let's see. Somewhere here should be volume, right? It says do not touch. What do you think? Do we ignore that? Let's happen if I turn this. Does that work better? Is that. Is that better or not? No. You can't hear that. Let's try this. How about there? Is that louder? Not changing. All right, so that maybe I shouldn't have touched that. All right, well, you know, I just told it. That's better if I hold it close. All right. So anyways, as I was saying last semester, we spent all our time prepping teeth, temping teeth. That's kind of what we did to get started. If you looked ahead at all at this semester schedule, there's a couple of things you'll notice. The first thing you'll notice is we continue doing that. The other thing you'll notice is that we change some of the temporaries we make. That's another thing you'll notice. And you'll also have seen that we do a variety of other things. And the final thing you might have noticed if you look at our schedule is that today is January 5th. And your final summative is March 1st. Now, depending on how you perceive time and its passage, this could either seem like vastly far in the distance or knowing how school plays out. This could seem like it's around the corner. And I think what you're going to find is, as the semester goes along, this second semester of our course, it's going to seem really, really short. Uh, it's just how the schedule is constructed. And so this is what the, your, your schedule consists of. It's what you've got. Now, one thing you may have noticed, if you looked at your schedule compared to the D2 class, you have one less summative exam than they took, all right. Or they're going to take later in the semester. So in your case today you're going to be practicing number 13 preparation. And another block temporary. And the reason we're doing this and it's going to be a graded exercise is as a way to actually have you have one last reminder of a block temporary. Uh, the D2 students are actually going to take another summative exam on the block. Temporary. In your case, we can't do it. There's no time. If you look at it and we try to squeeze in another summative exam, you'd have no time to get everything done. It's just how the schedule is. So instead, what's going to happen is we're going to run through various things. We're going to be doing preparations. We're going to be doing temporaries very soon. Starting next week, you're going to be using a new technique called the polycarbonate crown form. You'll do a couple of those. Um, going past that, we're going to introduce our final primary skill in the course. That's the preparation three by five, which is the same preparation you do for the CDK exam, which again, if you want to look ahead in the schedule, for most of you, you'll be taking that test in October. Now you know, day to day things take time. But October is going to be here before you know it. So we're going to have you practicing that skill in our class. You'll later on go on to practice that skill with Doctor Ferriero. He has a whole prep course for the exam, but we're going to have you make a temporary on it using a couple different matrix techniques. We'll introduce both of them in a few weeks. You'll have a chance to try them out and ultimately be tested on whichever one you choose. In the meantime, we're also going to spend some time doing things like an occlusal registration. You know, something that, uh, presumably you've all experienced, but we want to just make sure everyone saw on the same page in terms of how we conceptualize those things. We're going to eventually talk about restoring endogenously treated teeth. But as you look at the schedule, the key thing to be aware of is it's going to come at you really fast. There's not a lot of spare time this semester. So with that in mind, today in lab, we're going to post names of people who owe us exercises from last semester's lab. You may not know who you are, but when your name's on the TV, you will. And sadly, it's a lot of you. You have until the end of this month to catch those up and get full credit, right? You know, you know, these exercises, they're not particularly hard to do. It's just a matter of sitting down and doing them. So we're going to be posting names every week or two so that you can catch up if you don't catch up this last semester set by the end of the month, you won't get full credit for those exercises. And then the rest of the exercises from this semester will play out as the semester unfolds. Um, so that's what we're going to be doing. Uh. You really want to try to stay up to date on the lab materials and practicing the skills? Because before you know it, this this semester ends. And unfortunately, there's just not a lot of time built into it. So that's the biggest challenge for you. And it's it's worth mentioning and I'll probably mention that to you over and over just because it's it's just there, you know, it's a lot to get done in a short time. Um, at some point you may feel overwhelmed and one another of you may talk to your class officers to come ask me if there's any way we could find something to extend this and somehow relieve some of the pressure. And the answer is going to be no. There's no way to do it. There's nowhere to put it. There's nowhere to put you. There's nowhere to do this. And, um, it's just, you know, this is just the program you applied for, you got into, and you're in the middle of, uh, well, not the middle, the first, third, kind of first quarter. So. But anyways, that's what it is. So a word to the wise. Just be ready to keep up to date on this stuff okay. So what we're going to do when we get to lab today just to finish like a little preview of where we're headed, uh, as we start lab today, I'm going to go over the written midterm with you in lab. So we'll just kind of cover it real quickly. There's not that much to say about it. Most of you who recall it at all will probably remember it as being pretty easy, because it was. The scores were quite high. It's not meant to be difficult, and fortunately, overwhelmingly people did well. But I'll go over those concepts that people had trouble with. The other thing we're going to do when we get to lab is we're going to break up into small groups for little discussions. We're going to do that this week. We're going to do it next week. Uh, later in the semester. We're going to do it another time, kind of as a culmination of of the things we hope we learned this year. And, um, those are things that, uh, the faculty loves. I mean, they love the chance to sit and kind of chat about clinical concepts with you, and hopefully you'll enjoy that, too. And with any luck, you know, learn things. Um, any questions about this semester or where we're headed or any of that before we we kind of get going here. If you guys want to sit down, there are plenty of seats you don't have to stand, so it might be easier. So anyways, what we're going to start with today is um, we're going to start with. Um. Where's the. There we go. All right. We're going to start with, uh, alternative temptation techniques. So last semester we focused, as you're well aware, on the block temporary, which is certainly not an alternative tempering technique. It's, you know, it's a common enough one. With any luck, you achieved some mastery. Most of you did reasonably well on that exam. So that's good. I would encourage you, those of you who did, you know, sort of develop some degree of skill with it that you'd be willing to keep working on it. It's actually a very valuable skill. You never know when you're going to find it useful in an office on a given day. When confronted with a situation where it's a valuable skill for what it's worth, when I introduced it, I told you that in my case, I still do block temporaries you know, kind of like every day, single units, you know, two units splinted, sometimes three unit bridges. I do a lot of them. Obviously, I've done this a long time. So when I make a block temp, you know, kind of in a hurry in the office in 15 minutes or something, that's fine. But with practice, anyone can use these techniques. And arguably it's a very valuable technique. One of the things you'll find when you use a matrix, and many of you have familiarity with a matrix, temporary technique when you go to do it. One of the great problems we see, and we see this constantly in our clinic, and in just a moment, we're going to talk about a whole bunch of different matrix techniques. But one of the great problems you have has to do with materials. You're going to get to our clinic, and the first thing you're going to hear from everybody up there all the second year, advanced standing students, all of the third and fourth year, D 2 or 3 D four students is oh, it's great. You can just use prototype. You squirt it into a matrix, you slap it down in the mouth. Don't have to do anything except that because the material doesn't have a lot of body temp or the other composite materials, it can be difficult to actually capture margins, especially in any areas where there's any depth to the preparation. You may have experienced this in the past, but when it's the great problems we see as clinical instructors, there is that students make temporaries that fall short of a margin. Somebody misses it when it's done, patient comes back a week later, and now there's tissue overgrown into the bottom of a, you know, the bottom of the prep. It's just terrible. And the difficulty is that the material doesn't lend itself to being pushed where you want it to go. Using acrylics allow you to handle the material differently and to sort of push it where you want it. The value of knowing multiple techniques and multiple materials is the ability to make the right choice in each situation. And so that's what we're we're sort of aiming for here. And hopefully when you get to the clinic. So if we're going to talk about alternative temporary techniques, you recall our little picture from the past of the sad teeth that aren't covered with temporaries. And so they're uncomfortable and unhappy. We're going to cover a lot of different techniques, uh, you know, relatively quickly here. So the first thing we're going to talk about is a really simple basic techniques. We're going to use an auto polymerized resins. So that's the same sort of material you've used so far. Right. So the same a like you've used is, you know, common auto polymerized resin. Any of those materials are fine for this. And what we're going to do here, just to see how simply you can create a matrix, is we have a quadrant tray. And this is a kind of um, what would be sort of a, um. Well, this doesn't work very well. It's sort of a, um, a universal quadrant tray. And you can still purchase these if you like. It has a little hinge here, so you can use it, you know, in the back of the mouth you can use these in the front of the mouth. You can just sort of shape it however you'd like. But what we're going to do here is we're just going to take some base plate wax, warm it a little bit, stuff it into this tray. So this is the kind of thing you might do if you're trying to create a matrix really quickly and you don't have a model to start with, right. Patients sitting there, you want to make a temp. You sort of stuff this in there. Our patient that we're looking at is missing a tooth. Now this is not an ideal technique in a situation where a tooth is missing. But if it was an emergency situation where for some reason the patient had to be dealt with that day, you could adapt this as you'll see. So you're basically just going to seat this in the mouth, you know, with the wax warmed. So it's softened. One of the things that's nice about using waxes is that if you soften them a little bit, see them, all you have to do is blow a little bit of the air water syringe on it for a moment or two. It hardens as much as the wax does. Pull it out and you've got a quick kind of impression of what's there. Now obviously we have wax there. So what you're going to need to do is gouge that out. This is where the technique is not perfectly ideal, because it forces you to actually carve some anatomy, which, you know, the challenge for dentists, if you get too reliant on matrix techniques and you don't want to actually carve any anatomy or it becomes problematic. So, you know, the thing for Dennis is, you know, all these things, I mean, it's more of an issue for the d twos. You know, they're studying dental anatomy, right? Well, the d twos aren't. The D ones are studying dental anatomy right now. And in some level they probably like geez, I don't know. Is this so important? But you know, you have to know what teeth look like. It's the only way you can make your restorations look like teeth. So anyways, you carve that out, you go ahead, prep the teeth in the mouth, and then you're going to stuff some acrylic in here seated in the mouth. Let it get enough body that you can pull it out when you use a matrix. One of the key things about any matrix technique, and we'll talk about this over and over again, is that you have to pull it out of the mouth at the right moment. If you leave it too long, so that when you remove the matrix, the acrylic stays on the teeth. It's kind of a disaster, because if you wait for the acrylic to really firm up, it locks in. So now you've locked it in the mouth. Problems? You have to cut it out. Everyone is unhappy. Patients in pain. They lose faith in you. You know your day is ruined. Their day is ruined if you don't get it out within the matrix as you see here. But it sits in the mouth and now you want to yank it out before it firms up too much and locks in. Once you grab it, chances are you start pulling on it and it distorts so the value of the matrix is lost. So you really have to get a sense of what consistency the acrylic needs to be at for you to pull it out. When we do our skill, when you do the matrix technique in our class, the biggest challenge you'll face at first, and this is something I'll stress over and over again to you, is to practice mixing acrylic, sticking it in your matrix. Stick the matrix in your patient's mouth. Pull it out with the temp in the matrix. You want to practice that over and over again so that it's something that you know, absolutely, positively is going to work for you every time you try to do it. We always have students who don't practice it a lot. They get to the final and all of a sudden they can't seem to get the temps started correctly and they're in trouble. But that's the key. You have to get it out in there, wait for it to set, and then you can go on. Now, in this case, what's going to happen is as you wait for that to set, what is acrylic do? It gives off heat. Therefore this quick wax matrix is now distorted. So the problem with this technique. Well let's go back for a second. Well, to finish the problem with the technique is it's a one time thing. So if you have a patient and you're making a matrix because you're about to prep and temp and do these things. So now you've made the matrix. You set it aside, you prep the teeth, you go to do it and you mess it up. What have you got at that point? You've got two prep teeth and nothing. So hopefully you did practice making the block temp, because at that point you could make a block temp. But the whole point of the matrix is to avoid that to speed the process. So if you don't do this properly, get this in and out of the mouth intact. It's a problem. The other thing to notice here, and this is something we're going to also emphasize when you do the technique. Notice not only was this sort of gouged out to create a Pontiac, but can you see that the acrylic is a little extra thick here and here in the margin areas? One of the things you want to do with the matrix is you want to always provide a little extra thickness of acrylic. You want to sort of either cut it back or if you make the matrix of something you've applied wax to, you want to add wax to make sure that you bulk this area up because you want to have extra material. And this applies to whether you're using, um, you know, acrylic or whether you're using composite to make your temp. You want extra thickness there, because sometimes when you seat the matrix, in fact, most of the time you're not going to have the temporary you create have a perfect margin on the tooth. So if it's a little short and you're using a material like composite. It's hard to add. If you're using acrylic, you could always salt and pepper it, but so you'd rather have excess so that you can carve that back to capture the margin perfectly anyway. So there you carve it up. Make your tap. So. Advantages disadvantages. The best thing about it is it's really simple. It's fast. It's cheap. So it's one of those things that if you have the stuff laying around the office and everyone does, you can do it, but you can only do it one time. So that's the one big negative of that kind of technique. So you can also do this kind of thing auto polymer polymerized resin or composite in a vacuum for matrix. This is one of the techniques you're going to do in our class. Um we're going to demonstrate how you create these, how you create the vacuum form. But you're not going to be able to do it in our class because we don't have enough lab facilities. We don't really have a true wet lab for you to work in to make the models, to do the different steps. So we'll demo it. But we're going to actually the faculty is going to create these for you. So what you need to do in a case like this, if you're going to use something like the vacuum form, you have to have a solid model to work with. Right. So this is a situation where you can't do it. That moment in the office as a kind of, oh, here's a patient, I have the time. Let me prep and temp. This is a situation where you have to start with a model. So you need the extra time. And the other thing you need to do if you're missing a tooth as we were here, you have to add a tooth. And the key thing because the vacuum form generates heat is you can't alter your model with wax. You could wax up a tooth, but then you'd have to duplicate the model, because if it's wax, when the hot, um, material hits it, it just melts. So this is sort of our cast sitting on the Vancouver machine. You're probably all familiar with these. Well, don't raise your hands, but probably all of you have seen these and worked with these. It's it's a very, very common thing in dentistry which you see up here. This sort of arc here is the material kind of being softened. So the way the vacuum form works for anyone who might be unfamiliar with it, there's a heating element way up here. Underneath here is a vacuum with a little holes. And so you basically raise this, uh, piece of it with the vacuum for material. It softens a little bit. You pull it down, turn on the vacuum, and it sucks it into the shape you want. So what you want to see here, as it says, is notice how this has sagged an appropriate amount. You don't want it hanging all the way down here. It's distorting. It's too much. But if you don't get sort of a proper softening of the material, you're not going to get the proper adaptation. So this is the vacuum, you know, sucks it down these little holes or where the vacuum sucked it tight. And then you can take it, trim it up however you'd like and then you can use it. This is just another one might look like as you take it off the machine. Right. You cut the matrix out, you can see where we're going to cut it out of there. We're going to do this for you. The only thing you're going to do with these in class, and I'll show you how to do this, is you might have to trim this initial thing we create. You know, we're going to we're going to cut it out in a rough way. You may have to shape it a little bit, but beyond that, we don't have the ability for you to make these yourself. So that gets trimmed up a little bit. One of the key things about any matrix technique, and this applies to every matrix technique. It has to be properly supported. You have to be able to put it back in the mouth accurately. So the key thing is if we were going to be prepping, you know, from 29 to 31, this was a missing tooth. You need a solid support back here. You need a solid support up here. If you don't have that, what puts it in the right place, especially in a place like this on the lower right, say there was no 31 here and you wanted to do 29 to, uh, I'm sorry, no, 32. You wanted to go 29 to 31. What's the tissue like back here? You guys have been taken removable, or is that class done? No. You're still doing it. It is done. You're doing partials now, right? All right. What's the tissue like back here? Is it firm or is it compressible? It's beyond compressible. It's like flabby and soft. Right. So if you were to take this matrix and you've prepped this tooth and now you're trying to position it, what holds it in place, right. So in a spot like that a matrix is just not a good technique. It really isn't because it's very hard to make it work well as it is. We've tried in our patients mouth. We've prepped the teeth. We're going to mix up some acrylic. We're going to seed it in there. You're going to try to seal it completely. And it looks like we did. Now one of the problems with the matrix technique. And you guys may have experienced this in the past because you've you know, you've gone to dental school. You've done these things. When you pull this out, you trim it up. You go to try it in. What happens every single time with a matrix? Temporary. I precluded whoever said it. Yeah. Every time, you know. You know how they say there's exceptions to every rule. I mean, probably there are here too, but I don't know, you know, whatever more decades of dentistry than I'd like to admit to. I've never seen a matrix temporary that isn't hyper occluded, no matter how carefully and tightly you see it, they're always hyper occluded, so that's okay. The key thing about it is you just have to know that that's going to happen. You have to expect it. And plan for it. That's the key thing. So they're always going to be a little hyper occluded. But we seated completely. Once again we have to pull it out of the mouth so that the temporary stays in the matrix. If you pull the matrix out and the temporary stays in the mouth either because the acrylic was too soft, too runny, so it just does, it just stays there as a goop. That's a disaster. Or if you wait too long and it locks in, that's a disaster. So you have to get that out in the matrix, and then you just simply set it on the benchtop, wait for it to harden, and then you peel it out of there and you go on. All right. So then you're going to trim it, adjust it, put it in the mouth. If you're using acrylic you probably will need to realign. You may not. It'll be up to you to decide based on the fit. If you're using the composite materials, they're not made to be realigned. In fact, they can't really be realigned effectively. So either it fits or you do it again. Okay. So the advantage of these, it's a fast technique. It's simple. It's a cheap thing to do in your practice. The vacuum for machines frankly aren't very expensive. But you have to have a machine. The problem with the vacuum for matrix though, is you can really only use it the one time because when you peel the acrylic out of it, it typically distorts that matrix. So you don't use each one over and over again. And in our class, the same thing will apply if you choose to use the vacuum form and you're practicing the skill, you'll have to keep, you know, getting new ones from us, and we'll have them, you know, there'll be plenty of them for you. But the biggest challenge is to make a vacuum for matrix. You have to have solid cast to work with. Now, one of the requirements when you get to the clinic here and I don't know, have you had any of the classes or any lectures introducing you to the clinic and rules yet? Probably not. So those will come up one of these days. And one of the things they're going to tell you about doing fixed prosthetics in our clinic is every single time you have a patient that you might be doing fixed on you must have study models. Now, of course. There's more to it than that, because every single patient you work up as a new patient here, you're going to take alternates and make study models. But but no instructor in the clinic is going to ever let you do any fixed prosthetics if you don't have study models to work with. And part of the reason is for stuff like this. Bless you. So you can also use these same kind of techniques in other ways. Here's another kind of a sort of emergency technique using alginate. Something as simple as that. So here the patient shows up. The esthetics. The rough shape of the teeth are kind of workable, right? It looks okay, but he's got this tooth that's really failing. It's resolving. And this isn't a little bit of resorption. Have you guys studied this resorption yet? This. Okay. So this is a horrific reserved tooth right. It's really melting away. It's been, you know, bonded to the neighbors to hold it in place. And so at this point we need to tamp them. Well a good quick way to make a matrix if we want to do it that day. Easy way to do it is we're just going to make an alginate. So you know it's a good idea. Rinse off the blood. That's kind of disgusting. And then we're going to prep the teeth. One of the things you need to do is you're going to have to go in here and cut some of this away. Remember, you're going to need to create connectors for your temporary to be adequately strong. So you don't want to use a matrix always just how it first presents. But you want to adapt it to make it better. So as I described with the wax, you want to carve away a little excess in your margins. You want where there's going to be connectors to cut away, because you can always cut back excess acrylic or excess composite. But it can be hard to reinforce these things if you've made connectors that are too small or if you've come up short on your margins. So we're going to cut some of that away, and then we're going to go ahead and start to prep the teeth. A quick preliminary impression there. We're going to cut that crown off there right. And then we're going to stick some acrylic in there. Place it in the mouth. You just have to make sure it sits completely or as well as possible. Pull it out. And we're going to go ahead and start to trim that up and create a temporary. So you can do that kind of thing quickly. Once again, it's fast. It's simple. It's cheap. You know, it's about the cheapest stuff you have in your office, right? So you have plenty of that. But again, this is going to be a one time matrix because you're going to pull it out of the mouth. It's going to sit there. The acrylic in this case warms up. Um, for the most part the alginate can't go in and out of the mouth that many times. So it's kind of a one time. And this is only going to work for you if the tooth that you were going to replace was intact. If the tooth's not intact, alginate is not the sort of material that's going to lend itself to being cut away or gouged out, much like that wax did in the first example. So that would be a challenge here. So there are other situations. This is, uh, we're going to look at something where you have an emergency that arises. So this patient calls on a given morning. She had a bridge that has sort of broken and fallen out of her mouth, and it's gone. The fact that it's gone is important to us, because very often a patient has an emergency where something's really broken and fallen out, but they come back, come in with it, and in some cases you can work with it and that could save you some time. But she's going to show up like this okay. So that's a problem. Now for what it's worth, you could say to the patient, well, come on down. We're going to make an impression and you'll go home because we need to wax up to full contour what these teeth should look like after we mount the casts. And then after we do that, we'll duplicate it and we'll make ourselves a vacuum form, or we'll make a putty of that wax up, and you'll come back tomorrow and we'll temp you, right? You could do that if she's not in pain and there aren't other problems. But what if the patient needs the temporary that day? Right. So what could you do for her? You could make a block tab, right? Now, the other thing about this patient and just kind of. This is true, but it's sort of a joke. Um, you know, this is a patient we like. She's a really nice lady. Right? So it's not even a patient we all hate. So, you know, there are there are patients. You've you guys have most of you have practiced some dentistry. All right. So there's patients you're glad to see in your schedule, right. There's patients you're not as happy to see. This is one everybody in the office really likes. She she's a really nice woman. We really like her. Um, and she has another great quality, which in dental practice, in private practice is important. She actually pays her bills, so she's great. We really like her. Now, the thing about this woman though, to know besides that is she teaches at a law school in the Boston area and she has a lecture to give that afternoon. So now she can't go to her lecture looking like she doesn't have teeth. So we have to get her in. So we rush her in. This is what she looks like to start, okay. And we're going to make a block temp as you guys said. So this is no different than other block temps. It's just a little bigger that's all. So we start with our initial block. You see our imprints here from the opposing teeth. And the same as we talked about last semester with the regular block. We're going to use this the same way. You know we're just going to take it. That's what it looks like starting out. Okay. Um, now, for what it's worth, I don't typically draw, you know, our landmarks like we had. You do, but for the illustration here, drew some landmarks on it. This is the same thing that we encourage you to do in class. Figure out what you learned from the bite as it presents, and that tells you the shape the teeth should take. So we just marked it. This is where the Pontiac is going to sit. You know, we can see where our contacts are going to be. We have our basic set of birds we're going to use pretty much the same as you used. Right. We're going to do some gross trimming, same as you did, you know, gross trimming. Grind out the inside when you're doing a block or any kind of realign where there is a Pontiac. One of the things not to forget is to grind the underside of the Pontiac area a little bit as well, because when you see this, you don't want, you know, you can grind this out real well and this out real well, and you can make sure the occlusion is not hitting high. So you say, all right, this should be fine. So we can realign at the correct MIP position. But if you leave this resting on the tissue and it happens to be, you know, say firm tissue all of a sudden that could help to keep it hyper occluded. So you grind that as well and then you realign the whole thing. Mark our landmarks. Trim it up. So here's our temp. Okay, now, depending on how much time you practice the skill, this doesn't necessarily take a lot of time. It takes some time, but you know. But it's about practicing the skill. So here's our temp. It's been polished. And we're going to go and look at it in the patient's mouth. And what do we see. There's certain interesting things we see. What's the first thing we see that we don't like. We left an open contact. Am I going to beat myself up about it? With this emergency situation, I'm not. This isn't going to keep me awake at night. I'm not worried about it because, you know, we're not finishing. We're not making a final impression that day. We're not, you know, we're not doing any of the things where this would matter to us. And she's just thrilled to have teeth. Um up here. Notice this is in cross byte. So again the block temporary technique lends itself to these issues just by how it works. It sort of creates that for you. It's it's very simple. All right. So here's on the lingual right. And there's our temp. And this can all be made up quite quickly. Again, it's just practice. It's like any skill in life. You guys probably tie. You guys still tie shoes, right? Or is it just Velcro now? Or only shoes that you can slip into without bending over? Just flip flops. Yeah. We don't wear we don't wear shoes. But. Well, at some point in the past, people used to tie laces on shoes. And when you were little and first learning, it was sort of an arduous thing. With practice, you got good at tying your shoes. And so same thing with a block temp. At first it's hard and it's slow. After a while you do it pretty quickly and it's relatively easy. So here's our question. All right. It's cross bite. As I said I left an open contact that's on me. My fault. Um, but it's a good technique in an emergency. That's why part of why we have you learn it. Because it is a good technique, right? So there's other things you can do to make an emergency provisional. All right. So here we're going to make a matrix using polyvinyl Silac same material. So here's a patient presents with these failing teeth okay. You can see the patient already has a couple of temps back here. Fast. So this is how they present failing premolars. So what are we going to do here? Well, we need to fill in the space again. You use the simple tools you have depending on the situation and how you can manage it. In this case, we've just stuffed a little bit of blue wax, a little soft periphery wax in there just to get something. Very quickly using. This is a PVS material, which is meant as sort of an alginate analog sort of substitute for alginate. So it's in theory a little less expensive than some of the other PVS, but it doesn't really matter. So we quickly make an impression. You peel the wax out of there. Right. And then we're going to remember we talked about needing to make room for your margin of your temp. So you see how this fits. This is a scalpel trimming away some of the extra PVS to widen it at the margin area to better capture. To be sure we capture the margin, give extra acrylic to trim back. So it's a subtle thing, but it matters. So we're just going to throw our acrylic in there, stick it in the mouth. We're going to leave it. Just long enough. Right? And this is the skill. You have to know when it's ready to remove. Leave it to long. Disaster. Take it out too soon. Disaster also. The only advantage is if you took it out too soon. This is a matrix you can reuse. So that's the big plus of things like a putty matrix or pvz, you know, whatever of these materials. So let it set up, pull it out of there. And then we're going to realign it, as you see. And trim it up and put it in the mouth. All right. Simple enough. It's a way you can do these things pretty easily and pretty quickly. All right, so these are all essentially the same foundational concepts. It's just a matter of handling different materials a little bit differently, understanding the differences in the materials and how they're going to be affected by what you're doing. Right. So another kind of technique you might use. And again this is all just different tools you might keep in the toolbox to pull out at different times. Here we have a patient who's presented. She has an old gold bridge here which is failing now. So it needs to be replaced. So we could make an impression. We could have a temporary made in advance. We could make one ourselves in advance. We could make a matrix of whatever model we have. But in this case. We want our temporary to be strong and you know, not to break and hold up. Well, all temporaries, we'd like that. We have a gold bridge. Very solid. Well, we could actually use that for our temporary, which is going to be about the most solid, temporary we could ever create. So this is what it looks like. For what it's worth, in a number of weeks we're going to talk about Pontiac design. So this is a Pontiac a replacement tooth. Notice how this lifts up off the tissue. And so that's what's called a sanitary or hygienic pontic, right. It's a very uncommon design nowadays because it's not very tooth like. A lot of patients may not like them, but they can be useful because they're very easy to maintain and clean. You know, just basic brushing, um, you know, can keep all this quite clean here. So arguably it can be a good technique. It's certainly one that exists. But I'll actually show you pictures of that hygienic Pontic again because you don't see that many of them. Uh, so we tap off the bridge. All right. So we were able to keep it intact. This is what we find. This is an old Indo tooth. You know, a lot of staining, discoloration, some issues. And what we're going to do is kind of clean things out a little bit, clean away, decay this and that and realign it. So if you want to put acrylic into something like this, what you have to do is take a rather coarse diamond bur and scratch up the inside of it really, really well. Gouge the gold up very well so that the acrylic, when it goes in there, will mechanically be sort of locked in place. And you can do that. So that's what was done. But what you're going to see in a second, which is interesting and worth worth seeing a couple of things. One, obviously this was an onley, and if we're turning it into a full crown, when we did that sort of realign, we had to capture the whole tooth, which you can do. You know, acrylic is something you can handle and push around here and there, in contrast to something like the composite temporary materials, which you can't really position that way, it just flows where it's going to go. So acrylic, you can really move. And the other thing to notice here, this was an endo tooth. So we cleaned out, uh, the dentist who had restored it way back when had left some URM in there. We cleaned that out. And just as a way to make something really retentive with unbelievable resistance, form, we basically just fit our temporary into the pulp chamber. And it happened to have a path of insertion withdrawal. So it worked. Now this is more than is ever needed. This is sort of an extreme example, but it's worth noticing to think about in certain situations if you have a short tooth. And where I see this over the years commonly would be teeth like number 2 or 15, where if you think about what you've seen in patients mouths very often on the distal and the distal lingual, they're very short. You know, the tissue is pretty high there if you need to crown a tooth like that. You're cutting it down one and a half, two millimeters on the occlusal, and all of a sudden there is no wall there. You start to say, where am I going to get any retention resistance on these teeth, right? Well, if it's a tooth, one of those teeth particularly. Or it could be other teeth that are very short. If you have a short tooth that has had an endo treatment. One of the tricks I like to do is after the end is done, I might, you know, fill the, um, you know, the pulp chamber with some sort of core material, but very often in the middle of that prep, then in the middle of that core material, I'll take a sort of huge, flat ended, tapered diamond, a big fat one, and I make a giant pothole. Right. So I'm substituting a lot of internal resistance and retention features with that giant pothole for the short outside walls of the tooth. So for those of you who are. Well, for those of you who are awake and listening and for those of you who are following that, it's it's again, it's a little kind of trick you keep in the back of your mind for those moments when you need to pull it out. It won't work on a tooth. That's vital because you can't, you know, sink a pothole into the pulp chamber. Yeah, again, it depends on how you feel about the patient. But and certainly you don't want to do it on a Friday because that phone call on the weekends really annoying. So but but it is on those instances where there's an endo tooth. It's a, it's a great little trick where all of a sudden all the retention, all the resistance you'd ever want is right there. And you don't even care if that distal wall is is little more after the occlusal prep than just, you know, a little bit of a bevel off the surface. You know, you can do those things. So it's just a matter of like understanding the concepts of retention resistance and applying them in whatever ways you can find to do that. So this has been realigned. We're going to re cement this in the patient's mouth. It's re cemented in her mouth right. It's temporary. It's fine. Um using this the best things about it you know obviously this is going to be a quick thing to do. It's cheap to do. The patient showed up with it. It's fairly simple. As long as the bridge is pretty intact. It's unbelievably strong in a case like this. And you could have patients show up with an old porcelain fuzed to metal bridge or something like that. You know, whatever it might be, you can do these things if it's intact enough to say, be an advantage compared to other techniques. But again, it's not something that every day you expect you're going to have the opportunity to do or that it could make any sense to do. So. Another kind of temporary we can make is the processed, you know, heat cured temporary restorations. So this is what we commonly describe as a process temporary. These are made much the way a traditional dentures processed. Um, did Doctor Schnell described to you both like how they might be made where they're printed versus how they're processed. Right. So the processing where the acrylic goes into a flask and it's cooked is essentially the same way these are made. So here's a patient who presents, like this kind of a mess. The biggest advantage of these, and we talked about this before, um, is that, you know, these are great if you have to manage real esthetic change, if you're doing a lot of teeth all at once. If you're changing things about the function, you know, about the occlusion, things like that. They're great because they're set up in the lab. It saves you a lot of time and can create great esthetics. So this, you know, is waiting in your office. It's made in advance. All you do is prep the teeth, clean out decay patch however you want to realign it, trim it up, adjust your occlusion. You're good to go. All right. Here's another patient who presented. So this patient showed up like this. And. The patient, um, had experienced a rather, uh, common problem. And this was something that a lot of people have in their houses that are dangerous and they're not always marked. So, you know how you might have something like a, uh, ant poison, you know, or roach poison and it says on it it's dangerous. Well, this patient, uh, this tooth broke at this moment because of a dangerous household item. What happened? Is he, um, you know, this tooth had had issues in previously in the patient's life. You can see where it had had, uh, apical surgery, things like that. But what happened to the patient that actually caused the tooth to fracture? Because this tooth is fractured now, is he, um, he had a little child, a toddler, and this creature that he had at his house, he, um. It was sitting on the floor. Those were its pronouns. It it was sitting on the floor and he bent down and the the kid jumped up, and the top of the kid's head whacked his tooth. And it sounds crazy, but you see that kind of thing a lot, you know? I mean, at different ages in life, people find different ways to break teeth. So you guys, most of you are fairly young. So the way you've broken front teeth is probably playing basketball or, you know, soccer or something. Catching an elbow. Oh, sure. Opening a beer with your teeth. Yeah, absolutely. Um, you know, doing something really stupid at a party, falling down. You know, we all. It's amazing any of us have front teeth, right? By the time we're 25. But he was a little older, and so he'd done other things to harm the tooth earlier. But what finally killed it was the toddler. So the tooth broke and it's fractured now. You can see it. It had endo and stuff. You know, he he'd had problems. So what we're going to do here is it wasn't really falling out of his head. And because it was a non-viable tooth it didn't really hurt. So we made an impression, made a cast and had a process temporary made. So there's the model that, you know, temporary. This was pulled out. You can see what was left to the apical surgery. Here's the fracture that, you know, killed the tooth at the final moment. And basically all we do is we realign this, put it in the mouth. Right. So a process temporary can be quite esthetic. That's the biggest advantage of them. They save you a lot of time on the day of the procedure. They can be enormously esthetic if you want to, you know, if that matters. It's a great technique. And this was the final restoration that was made from. So the thing to know is this was made a lot, a lot of years ago. So what would have changed between when we did this and now? No, not the pink. Well, implants. One thing that might have changed, but those neighboring teeth remember those had endo two. They were damaged. So I don't I don't mind doing the bridge, but what would we have done differently now from then. Yeah, tissue grafting, things like that. Um, you know, when I did this a lot of years ago. And this is this is old. That picture. Um, the ability to to fill in that defect was not there at all. Now, would that defect fill in? Now, I don't know. You know, Doctor Fleisher, maybe, you know, he could do some magic and do that. You know, he's good at it. Or used to be. I don't know if he's still doing procedures, but, um, but, you know, but, you know, find even the most the biggest wizard of an oral surgeon or periodontist. They may not have luck with that. That's an old, you know, lesion that's an old mess. But the ability to fill that in is has come. And it wasn't there then. What we would do now is probably, you know, put a temp and then try to have the patients see a periodontist or an oral surgeon and try to graft the area, try to fill that in to get a healthier site, a better place to work. Would the patient agree? They might, they might not. Some patients would care, some wouldn't. It would depend probably where their smile line was. So that would be one of the differences. So here's a patient who presented in the office like this. All right. Now. I'll be honest with you. I've done this a long time. This might be the ugliest thing I've ever seen. Well, and I shouldn't say that I've seen a lot. You see a lot of gross stuff, but this is one of the worst. This patient presented. What's that? A Krazy Glue. Now, uh, you know, I don't know what she was using. It was a she. I'm pretty sure that she wasn't using a toothbrush. That's a that's probably a good guess. Yes. You know, fortunately, when you when you're when, like, all of us dealing with, you know, people who are somewhat informed and educated about dentistry, we're able to look at things and discern those subtle clues. So but so that's yeah, it's very good that we can see that. But I agree with you. He she probably didn't brush. Here's the story about her, which is sort of interesting because sometimes, you know, the fun of dentistry is always the stories. It's who the patients are. It's not the dentistry, because that after a while that just gets boring. Um, but the patient. It is actually a nurse. Isn't that gross? I mean, you know. How would you like to be in the hospital, you know, and you and I. Yes. Yeah. So she's a nurse now, obviously. You know, to be fair to her. She clearly has some sort of absolutely pathological fear of dentistry, doesn't she? You know, you don't get this way because. And toothbrushing. Yeah. Yeah. That's right. She had that dream. She had that dream about being attacked by a toothbrush. Yeah, yeah. Very scary. But as it is. So she presented this way. And so what did she ask us to do the day she came into the office? Well, no, she didn't ask for whitening. That would have been even better. She didn't ask for whitening. What she asked for is, could we just re cement her temp? Because parts of what's under there is some sort of a temp, I don't know. Well, the answer, when you see certain things that, you know, the patients are going to come to you at times and they're going to be asking you to do things for them that you know you shouldn't. Right. That happens. Um, I had an assistant and, you know, you're Dennis. Dennis, we go to dental school, we become dentists because we're trying to help people, right? We feel that, like the things we do all day are benefit in their lives, and that's a good thing. So, um, so Dennis can be very susceptible to a patient sitting there going, well, couldn't you just re cement this today? I'm really busy at the moment. And, you know, and you're sitting there because, you know, you're you're a nice guy or a nice woman, you know, and they're, they're begging you and you want to help them, right? So what you need to do, what I used to have was a great thing. I had an assistant who would sit behind the patient while I'd be talking to him. So I'm talking to the patient, the assistant sitting in her chair behind there. And when the patients start with that begging, could she just she'd sit behind him and do this. So she'd remind me, no matter how much you want to help them, help them by doing the right thing, not agreeing to whatever garbage they want. So the answer was, you can't know. We can't re cement it. You have a problem. Here's what we have to do. So a plan was made to make attempt. The plan was she was going to see a periodontist I work with a lot. And he was going to extract a whole bunch of teeth. And he was going to try to graft and place some implants and things, and then she was going to come back to my office, and I was going to place a temporary in her mouth, and we'd pre-planned that. We were going to support this temporary, this process temporary with whoops with, uh, come on now. All right, here we are with two molars and the two front teeth. Now, those are very long spans. So if you're going to make a process temporary of that nature or any kind of temporary, it needs strength. So what's going on inside here that you can't see is there's a cast metal frame within it. And the cast frame actually scallops on the lingual of each tooth to leave room to later on, place abutments on the implants and rely on it to fit. So it has strength. And it's also built to adapt to future plans because we want the temporary to last her for a while. So she comes back, we put the temp in that was sort of before and after on her sort of initial day of dental treatment. Now, this was a lot for her because she doesn't like going to the dentist. We were kind of pleased that she actually showed up to see the periodontist and came, you know, obviously once the teeth were out, she came and saw me that day. So then some time passed. That's her before and after smile. This is her still numb. So you know people when they're numb, if you take a picture of their smile, they always look as if they had a stroke. Um, anyways, she comes back, we uncovered some implants, we put stock abutments there. We reshaped them a little bit and realign the temporary, as I was saying, okay. And then she's supposed to go see the periodontist so he can remove these other couple few teeth, place some additional implants, and then we're going to proceed. So. I'll give you one guess what happens next? Nobody's ever seen her again. Which isn't that much of a surprise because, you know, as a dentist, you're always trying to tell yourself that, oh, you're being so kind. You're being so caring, you're being so gentle that you're going to be the person who won over that terrified, you know, pathologically frightened patient. And they'll all of a sudden transform, you know, from, from, um, you know, the ugly duckling into the swan dental patient and they'll, they'll be coming in regularly for checkups and they'll do all that. And, and, you know, that'll be your great achievement for the month. She never came back, which is what happens. So that was before and after. Um, and that was what happened there. So anyways, that type of temporary. All right. It's great for multiple units. It allows you to, you know, control or alter the function and the occlusion. The esthetics can be great negatives lab costs. Right. You have to pay someone to make it. And it can take some time to do that. And you have to plan it all in advance. This isn't something you do on an emergency basis on a given day. All right, so, uh, the polycarbonate crown form another sort of temporary restoration. We're going to use these in class next week. And the week after you're going to work with these. So you'll get a chance to see how these work. So they come in a variety of sizes. They're especially valuable right in the front of the mouth. That's where I like to use them. They come you know you basically just want to find one that's about the right size and shape. You alter it as needed. And I'll go over that with you next week. How to how to adapt these. You realign it. Shape it up. Good to go. So here's a patient presented like this. Okay. Kind of ugly. All this. We need to temp them, right? So what we did is we took out some polycarbonate forms without going through all the steps we got to that we liked for the Centrals. We kind of realign those on there. We decided the length we wanted shaped them. You know, we took another one. You know, shaped it these easily. Just splint them together. You just, you know, put a little bit of the acrylic, you know, wet them, get the acrylic, diffuse them together. And in this case we had a four unit splinted temporary very, very easily. Now could we have had a process tent made in the lab? Absolutely. The reason that didn't happen in this case, this patient. Was fairly simple. It was that the patient was, um, for whatever reasons in his life, was so anxious to start as quickly as he possibly could that I said, all right, sure. You know, we'll get you back whatever, in a couple of few days. Or the problem with the process temp is you typically need, you know, a couple of few weeks for it to be made in the lab. And if the patient wants to go faster. And in a case like this, you feel that you are comfortable enough with a technique like this to, you know, to temp rise it, you can do that. Again, it's all about having options, all sorts of different techniques, different tools that you can pull out and use. So this is what he looked like before and after. Um, you know with the temp. All right. Good thing about these. They're very quick to use. They're easy to use. They're pretty cheap to have in the office. They give decent esthetics. They're an interesting technique because you know they come one color. It isn't like you buy them in 12 different shades. They come one color. But when you look at them, if they seem a little bright, so you use a kind of dark acrylic in them and it's amazing. How close they'll get, or if they seem a little too dark. Sometimes you put a light acrylic and you get away with it. They blend into mouths shockingly well, and the biggest key to them, blending in for what it's worth, isn't so much the color. And this is the. This is true of a lot of things when we talk about color science and shade selection and dentistry. One of the things I'll try to illustrate to you is that as important as color is that a tooth is shaped properly. You know, if a tooth looks like it belongs in somebody's mouth, that's when it looks like it belongs there. Sometimes the color can be wrong on some teeth, but you know, any looking at any of your own mouths or your neighbor's mouths, you know, your teeth all look like they belong together. That's how nature makes them. So if you can make whether it's temporaries or or crowns for patients and they are shaped, you know, fit like they belong there, very often you'll succeed even if color isn't perfect. So you can get decent esthetics. You can only do so many of these at once. Doing four units like that is pushing them, I think, to the outer limit. But you know, and again, as I said, the esthetics are limited. You can only do so much with them. Yes. Yeah. So the question is, could you make them one by one and just cement them or do more like that? The answer is absolutely. You could what I like to do with Temporaries if there's multiple units, I very often like them connected. And the reason I do that is, um, it's a somewhat selfish reason. It's that they're going to fall out less often now. Overall, I don't have that much trouble with Temporaries loosening and falling out, but depending on the patient, the foods they eat, how they care for it, the retention you can obtain, all those things you know, temps do. Temps loosen and fall out? They absolutely do splinting things, even if they're going to be single units in the end, is often a convenient way to put a temp in and not have it loose and come out. And for the patient, that's an advantage too. It's not just, you know, selfish for me that I don't have to see them in resubmit. It can also be that they don't have to come in and have it re cemented. So very often temporaries that are connected together are a big advantage. So. But you could absolutely do as you ask. All right. So that's the end of that. Let's do this next. Because we still have other things to do here, which is the nature of our, um, semester. Um, here's what I want to do. Let me project this other thing here because we're going to do attendance. So let me find that. So get your stuff out. All right. So I'm going to darken the I'll darken this again. So that should project well. And this should work. So see if you can do the attendance for the class. Anybody having luck with that, I hope. I saw it just refreshed, which that shouldn't be a problem. You guys get that? You get in the code. All right, all right, so what we're going to do, uh, in just a moment after you've scanned this is we're going to go on to another topic, um, which is going to be talking about impression materials. So we're going to do that next. But um, we're not going to take a real break here just because we don't really have time for that. You can slide around or. SPEAKER 1 Oh, yeah. Okay. SPEAKER 0 So you guys get. Did you guys get the code? You all set? See if you can get that, because I want to, um, we should move on to our our next thing. SPEAKER 1 But in the case of Ebola, this patient. Black metal frame. Under the stress inside. Yes, but. SPEAKER 0 You know I make it. SPEAKER 1 You make it. SPEAKER 0 Mad, pastor. SPEAKER 1 Asked the battle. SPEAKER 0 To fit into. Attractive. SPEAKER 1 I basically do the best. Basically, they're going to put the frame where the tooth would ideally align in the chest, and then we ask the president to try to hit the mark. And if you're out with your. A lot of times the kits are perfect, but we don't care. It's running out and. I didn't expect that day. So depend on how much you talk to us. But we might look out for a bottle and make the effort to find something removable. There's all kinds of ways you can deal with it and then come back for a fix. So, you know, you do what you. SPEAKER 0 All right. Are you guys all set with the QR code? So here's what we're going to do next. SPEAKER 1 All right. SPEAKER 0 Uh. SPEAKER 1 Let's see. SPEAKER 0 Um. SPEAKER 1 But. Okay. SPEAKER 0 Wonder if there's a way to. Oh, here we are. So what we want to do next, uh, in getting into our next bit of stuff in the course for this semester is we're going to be talking today about impression materials, and next week we're going to talk about actually making impressions. It says that this will mute the image. Which does not seem to be doing. What does that do? Noted. Okay, so in thinking about impression materials, you know, physical materials or for that matter, digital scans, um, I want to approach this in a certain way as a, as a way of thinking. Why didn't that do that? I'm trying to get rid of that image. Not that it's probably impossible for us, but. That seems better, doesn't it? We came back. Look at us. All right? Yeah. Yeah, but I need that in a little while. Um. All right, well, we'll live with it. So anyways, um, here's what I'd like to do. There's different ways to think about materials in dentistry, right? So on Tuesdays you guys take operative, right. You use materials. You're going to get out of here one of these days. And you're going to perhaps buy a practice or open an office. Right. So what composite do you use on Tuesdays? You must know. Somebody must know. You use composite, right? Something they hand you and you don't even know what it is. It has a name on it, right? Well, there's a reason. There's a reason doctor McManaman chooses it, right? Did he tell you why he likes the material, or was it just the cheapest he could find for class? That might be it. That might be it. All right. But so you're going to get to well, let's let's forget Tuesdays in a in in a short time. In a few months you're going to be in the clinic here. Right. And there's going to be composites. There's going to be, uh, different, um, impression materials going to be different things. Right? And you're going to be using them. And with any luck, you like using them. You get used to them. You're comfortable with them, they seem good. And then you get down with school and you go to your office, or maybe you get a job in an office, and the dentist there says to you, you know, I'm excited to have you here. Love having a new associate. It's exciting for me. And I want you to be happy. So we'll order whatever material you'd like to use. So you. What are you going to tell them? You say, well, whatever composite you guys use is fine. Or would you say, well, it's school they use. TF. So can I. Can we order that? And some years are going by and you start to think to yourself, you know, everything in life gets better or changes. I wonder if this TF, which is now like a ten year old product. I wonder if it's a good idea. Maybe I need a different composite, right? So how would you choose the next composite? SPEAKER 1 No. SPEAKER 0 Don't call me. Yeah. So the point is, the point is you have you have to. Right. You might say, well, I know what I'll do. I'll email Doctor McManaman because he knows about these things and he'll tell me the best composite on the market at the moment. Is this or that. Right? Or you might say, I'm going to go to a lecture at Yankee. Somebody's talking about composites, and they'll tell me what the best composite is. I remember trying that when I was sort of new in dentistry. We went and heard, um, a friend, a classmate of mine and myself. We went to hear Gordon Christianson. You guys probably know of him, very famous about dental materials, true expert. And we're excited because, you know, we're going to we're going to find out what are the absolute state of the art best materials we should be using now. And it was horrible. And it wasn't that he was bad. What was bad about it is he's like, well, if I'm doing a class four, I use this composite and if I'm doing a class five, I use this composite. And if I'm doing a, you know, class two, I use these two composites and all of a sudden you walk out of there going, I don't want to walk down to Yankee and buy six different composites. That wasn't the point. I wanted to know which one to buy. Right? But he he didn't break it down for us. But that would have been a good way to to find a good composite because he's an expert. Right. Or you could walk around Yankee, right. And you're walking around and as you walk past one of the booths, the salesperson looks really friendly. And they have what looks like pretty good candy in front of the booth. So you stop to pick up some M&Ms and, you know, Reese Cup and and they start talking to you and they're telling you about their composite and you go, oh yeah, sounds good. Let's buy that. Is that a good way to choose? Probably not. I mean, depending on your sweet tooth. So there's a lot of ways you choose materials. Um, now, what might be a really good way to choose a material? Is to think about what you actually want the material to do as opposed to, you know, well, my friend said they've been using this and it didn't stick to their instrument so much. So maybe that's a good composite or whatever. You know, there's there's a lot of those things. So what I'm thinking about and I'd like us to do here, is we want to talk about impression materials for fixed prosthetics. Right. So there's going to be different materials in the world. You may or may not be aware of the different ones. Um, there's also digital scans. We're aware of those. You've been doing those in class. But I don't want us to think about specific materials as we think about it. What I want to do is say, right, if I was going to walk around Yankee at the end of the month and look for the best impression material that I could find to suit my goals. One of the ways I could do it is actually to perhaps make a list of what do I want the material to do? What are the physical properties the material might have? And based on that list, I might walk around and say, all right, what does your material do? You know, some of them will meet certain of the properties, some of them won't. And perhaps by doing that, I could actually find the material that would suit my goals the best. As a way of thinking about it. And obviously this could be applied not just to impression materials, which I want to do today. But I was talking about composites. Before you could do that with composites, you could say, you know, the thing I care about most with composites is going to be sort of the where properties, and maybe I care about how sticky it is on my instrument, you know, whatever you like. So you look around, see the numbers that they have for where properties you might look at, you know, physically handle it with some instruments and say, you know what, this feels good. I'm going to use this. Those are ways you might make those choices. Right. Or anyways, so with the idea of fixed prosthetics, making impressions, both physical impressions, analog impressions, elastic impressions as we do or digital, let's think about what properties would we like for an impression. What I want to do, because I think this is an interesting way to do this, is I'm going to ask you, and this is why I mentioned reading a little bit about this stuff. Um, I'm going to ask you to tell me properties you might think of that an impression should have impression material, not the impression itself, but the material. And I'll write them down. And then we'll look at our list. And then what we might do is take a few minutes to think about the specific materials that actually exist in the world, and see how they match our list. And then based on that, we might say, well, here's what we might want to use and why we might use it. And as I say, this could be applied as a concept to other materials. It doesn't have to be impression materials. It could be composite or it could be, um, I don't know, whatever materials we use, waxes, whatever you're buying in the office, you know. The coats you wear. You know which ones are either. Is it about them being cheapest or most water repellent? Or, you know, can they be washed? How how wrinkly do they get? You know, there's a lot of different things we use in offices. Um, for those of you who have had dental practices, you're probably already aware of the vast amount of stuff you're buying all the time. Um, and those who haven't will at some point become aware of it, and it can be a lot to deal with anyways. So let's let's do that. Who has some notions. You can just kind of yell these out. What do you. SPEAKER 1 All right. SPEAKER 0 All right, Flo. We'll just say, um. SPEAKER 1 Over both. SPEAKER 0 Dimensional stability and accuracy. All right, let's write those. Here. Wait, give me a second. Because I don't write fast and I don't write neatly. Said detailed detail. All right. Biocompatible and details. So right. Bio compatible. And we'll just write details because that, that that's um, that that's kind of gets the idea. Ease of use, right? Okay. Ease of. SPEAKER 1 Use. Good taste. SPEAKER 0 So, for setting time. What are you thinking? Who said setting? What are you thinking with that? Yeah, but but I mean, so I heard. SPEAKER 1 Somebody. SPEAKER 0 So you're you're you're. SPEAKER 1 You're very. SPEAKER 0 You're very literal. Which is, which is fine. Um, but but when you say that, I guess what I'm getting at is somebody else said working time. What I'm thinking, I think what you're getting at is the idea that in in an imaginary material, forget reality. Like, just if you could make a material imaginary setting time, which you kind of want is something that you could control so that you could sort of put the tray in the mouth. Right or. Well, I'm saying imaginary. You put it in the mouth and then you wave your hand over the patient's face. You snap twice and set. You just had to say the right words. Right? Magic words. And that would be ideal. That probably doesn't exist, but it's it would be nice. So I'm going to write controlled set. SPEAKER 1 I ain't. SPEAKER 0 Cheap. All right, that's a good one, because we're. Dennis. Hydrophilic. Okay. Uh. Uh, resistance or elasticity? Kind of. Well, the kind of similar. Right. Um, elastic. And we'll say, um, we'll write tear resistance because that sounds slightly different. SPEAKER 1 What else? SPEAKER 0 Smells good. SPEAKER 1 Tastes good. SPEAKER 0 Smells good. What else? What else would we like it to do? What else besides smelling and tasting good. What else related to the the the sensory experience? You know, what is there smell to. All right. What what else is there? What do you see? SPEAKER 1 Smell good. SPEAKER 0 Taste smells good. How about it? If it looks good. Um. And you. You. There was one here that was valuable. Easy to read. Yeah, easy to read. Because, you know. You know, you're looking at margins and. Yeah. What else? Presentation. Oh, so how do you write? So. We were talking ease of use. That would be kind of like, um, auto mix. Yeah, I think that's where you're going. They change this change. Shade. It's a no. We're just making the impression today. You're getting way ahead of us. You're already, like, three weeks ahead in the lectures. Good shelf life. All right. We'll say long shelf life. SPEAKER 1 Oh, yeah. Yeah. SPEAKER 0 Very long. Yeah. Oh. Multiple pause. Right. What else should we do? What was that? SPEAKER 1 It. 3300. SPEAKER 0 Free refills. Yeah, yeah. Well, you know what we have, like we say, multiple pores. Um, talking about this stuff. Uh, years ago, somebody was suggesting, like, like reuse. You could reuse it. So you do it over and over again. So we could write that. Reusable would that be? I mean, that would really make it cheap, right? Kind of wipe off the the blood and stuff and. Yeah. SPEAKER 1 I'm sorry. SPEAKER 0 Oh. All right, all right. So, uh. Um, don't have to pore immediately. Yeah. Yeah. Um. Uh. SPEAKER 1 Yeah. SPEAKER 0 So it's right we have dementia stability. But yeah. Is that the same? Well they're a little different. They're a little different. Um, we'll just write way to poor because in a way they're related, of course, but, um. And you. SPEAKER 1 Oh. SPEAKER 0 Hypoallergenic. Right. Uh, tech. SPEAKER 1 Uh. SPEAKER 0 Well, we had easy to use kind of, kind of that idea. Yeah. Well, that's kind of the, um. Yeah, I think I think you're getting at the idea of, like. Yeah, that it holds a long, um. Yeah. Yeah. Oh, yeah. Easy to disinfect. Yeah, that would be important to us, right. Especially if we're going to reuse it. SPEAKER 1 That would really. SPEAKER 0 Help. Yeah. Oh, right. No adhesive. And probably stock trays. Right? Yeah, yeah, yeah. So, no, uh, adhesive. SPEAKER 1 Oh, man. SPEAKER 0 Stock. Yeah. No. Trey stock. SPEAKER 1 Trey or no Trey. SPEAKER 0 What else you got? Oh, no Gagging all right. Good. That's a good one. SPEAKER 1 But you know, the weird part is. SPEAKER 0 That actually comes into play when we talk about materials. It sounds crazy, but it will. We'll talk about them in a minute. Taste. Do we have. SPEAKER 1 Taste? SPEAKER 0 Well, not everyone. Some people gag. Yeah, yeah. But, um, any other ideas? Anything else we want for our. Again, this doesn't have to be real. It doesn't have to be a material you've seen or no exists. It could be just made up stuff, like we said, um, that it's reusable. SPEAKER 1 Eco friendly. SPEAKER 0 All right, eco friendly. Recyclable? Yeah. SPEAKER 1 That's right. Okay. Okay. SPEAKER 0 So it's it's very like, um, very elastic. So we had the plastic, but we might say, um. SPEAKER 1 So it'll pull out easily. SPEAKER 0 Anything else we want to put on our list? Vegan. SPEAKER 1 Yeah. Hey. You're gluten free. Okay. SPEAKER 0 That should satisfy most of our our, uh, our patients. All right, let me let me just take a glance. I had written some stuff down. I have some stuff on the list. Let me see. Uh, how much of this is there? Stuff that, uh. Oh, you know what? Uh. All right, well, we got most of these things here. Um. Okay. SPEAKER 1 Let's. SPEAKER 0 Well, we had, um, hydrophilic, um. SPEAKER 1 But. What's that? SPEAKER 0 Oh, yeah. Well, that's what we're going to talk about, is what I'm going to do is I want to in a minute we're going to look at actual things, including digital and kind of see how they how they line up. Um, well, let's do this. Let's work with, uh, let me add just a couple of things that I might have come up with in the past, um, that will consider, um. Hemostatic. So if you made bleeding, it's the impression material may be stops at for you. Um, and let's see. Let's see what else we had. Uh. Um. Just a couple other things here. Steyning. How about, uh. No, you don't have to. Let's do this. Here, we can look at this in a couple of different ways. We could go through what we've got here, and then we can also put up on the projector a list that mirrors this and also has some other stuff. And we'll we'll look at that, if that makes sense. Okay. So what are the materials we do have. All right. Because now we have a list of some imaginary things we'd like to have. So what do we have available to us? One thing we know we have available is going to be digital scans. Right. An optical scan. So obviously certain things. We'll be satisfied by that. You know? We know they're accurate. Um, you know, they're going to be stable, biocompatible, things like that. Right? Then there's going to be other materials we have available to us. We know we have polyvinyl selection materials. We have polyester materials. I'm going to mention one other material because as we talk about these, which is going to be hydrocolloid. So that's going to be reversible. Hydrocolloid it's going to be kind of fancy alginate for those of you who are familiar or unfamiliar with it, but basically it's a, uh, again, it's a very acceptable material, but it has its pros and cons, right? So what I'd like to do is let's glance through our list and look at these different characteristics and see how our actual materials may or may not conform to these. And then we'll add some others and sort of see where it leaves us. Because this is it sounds kind of silly to make a joke of it like I did, sort of about, um, you know, how do you imagine what you'd like? But it's not the craziest thing to sort of say, well, what would I what am I looking for? You know, as opposed to just walking around going, well, they had good candy. I'll buy their stuff. You know, a lot of times it could be like, does this meet my goals? And that's up to you to think what you're looking for. So if we're going to kind of start up here, um, let's just kind of go down our list and except for things, you know, match up. So the idea that something is fillable, easy to obviously administer and place where you want it to go, that it's going to go where you want because of the flow that's going to be important to us. Related to that, I think, uh, is going to be this where we say it's not going to cause anyone to gag because if it's too fillable, obviously that would seem like a problem. Now, interestingly, if we consider our different materials, um, digital, that's not going to apply. Although it might for gagging because if you start shoving that wand into people's mouths, not everyone's going to be comfortable with it. And in fact, as surprising as it might sound, that might be more of a problem with gags than some of the actual materials, depending on how big it is and where you're working in their mouth, how how big the wand is. So if we're going to talk about flow, there is a characteristic of materials that we talk about a lot. Um. It would be to say that materials are thick isotropic. So thick isotropic means a material that only flows under pressure. Now, if you happen to look up any of the materials we want to work with, or at least some of the common ones like the PVS materials, they're going to all talk about being fixed topic, because what that means to us and where that's valuable to us. In talking about flow or gagging. Is that if you have a thick isotropic material? You squirt it, say around number 15 when you're making an impression there. And it doesn't flow down the patient's throat when you have them laying back, it just sits there. And then when you seat your tray with maybe the regular body or heavy body material in it, it pushes your light body thick, isotropic material firmly against the tooth. It only goes where the other material pushes it so it actually doesn't flow. A truly thick, isotropic material has no flow. If you want to test that out when you're at Yankee and somebody says, oh my materials stick isotropic, squirt a little gob on a pad, take the pad and turn it sideways. If it just sits there like a little glob and doesn't move. That's a thick, isotropic material. All the materials, all the manufacturers are going to try to tell you that theirs do that. Some are better than others. So the idea that came up about non gagging, interestingly enough, there are materials that are going to be in that respect, less potentially gagging, less offensive that way than some others because they are thick isotropic, and yet they'll still have the flow you need because that type of material, as you inject it, as it comes out of the gun under force, it will flow, it'll go where you put it, but it'll stop once you stop pushing on it. So that's going to apply to PVS materials. Not so much to the poly ethers, perhaps a little. It will not apply to the hydrocolloid. And of course it's a lot of these characteristics are irrelevant when we talk about things like the scans because you know, there's no flow in a scan. So yeah, the scan just sits there. So accuracy, um, all the materials we're considering are accurate enough for our purposes. All of them are going to capture the detail we need. All of them are fine dimensional stability. All of them. The scan PVS, poly ether, all of those except for the Hydrocolloid have dimensional stability where you can actually make a physical impression. You want to drop it in a bag and send it halfway around the world on a on a relatively slow ground transport between here in California and have a crown made, you can do that. You know all the manufacturers will specify that they're accurate for two weeks. Hydrocolloid, though, because it's mostly water has to be handled very, very carefully. You make an impression and you either pour it immediately or you have to stick it in a humidor. And a humidor is going to be something that is essentially 100% humidity. So the simplest sort of thing you could do is have a Ziploc bag with maybe a wet paper towel sitting in it, not wrapping around your thing, but sitting in the bag. You could stick it in there, close the bag, and that will create a humid environment where you could wait a little bit to port, but you don't want to wait too long. You wait too long. It will begin to dry out and distort. So those characteristics though, that's how those break down in terms of biocompatibility. As far as we're aware, all these materials are biocompatible. All right. Related to that, of course we had some other concerns of where was it. Eco well, eco friendly and recyclable. Um, not non non poisonous. Whatever. Nontoxic we might say. So biocompatible. They're all going to meet those characteristics. Um, talking about related to that though, they're not all um. Uh, so eco friendly, you know? Um, for those of you who've worked with things like poly ethers or polyvinyl silk scenes, if you've made an impression for some reason, left one laying around and just left it laying around and laying around. Some years later, it's still sitting there looking pretty much like it was years before. I don't know if there's any research on it, how long those things last. I've always been a little suspicious that, you know, like in 500 years when the aliens come and and they dig through our, um, our landfills, you know how they say they're going to find nothing but, uh, disposable diapers? Um, and these, they'll probably find our, you know, polyvinyl oxide impressions and diapers, and they'll say, that's what this society cared about. Um, but because they they really last. They really last. Um, so and that has to do with part of their, you know, dimensional stability. Now, on the other hand, something like the Hydrocolloid would be enormously eco friendly. It's essentially made out of seaweed. So you could just I'm sure you could just flush it down the toilet and not harm anything. In fact, it probably contains good bacteria. Who knows? So those sort of things. Um, those materials are probably very eco friendly and they. I'm not sure that they're recyclable at all. The scans, of course, again, that doesn't apply. You know, the only thing about eco friendly with scans might be, you know, what sort of process goes into creating those devices. You know, you spend so much time nowadays reading about rare earth metals and you know, where they get mined. And who knows, it might be that that there's much more consequence to our digital scanners than we realize. Or maybe not, I don't know. All right, you're ABC, right? Right. The covers are not right. We go through a lot of plastic. Yeah, yeah, we. Yeah, we use a lot of that. That's true. So, you know, even that which arguably would seem like. Oh, this is great. SPEAKER 1 It. SPEAKER 0 Yeah. Those. You can pull off an autoclave. That's true. So but again, the autoclave, you know, all these things are their own issues. So that's how those things are gonna apply in terms of our deep concerns about these being vegan and gluten free. Um, I suspect that the Hydrocolloid is a great choice for our vegans and for our gluten free, um, friends. My wife. Um. Yeah. You think it's easy being married? SPEAKER 1 So. SPEAKER 0 But that's how that's how those are all going to are going to come out. Anyways, let's let's go on with some of these other things. So we've looked at these. We said they all provide the detail we need and the accuracy we want, the surface detail. All of that's fine for our purposes. Now if we get into these things like ease of use. That's an interesting question, isn't it? You know, when we talked about, um, I think we had on here like, uh, sort of easy to use, um, and maybe like a short learning curve, that kind of thing. Auto mixing. Those are going to vary. Um, and the challenge of all of these, including the digital scans, and you've probably seen this a little bit yourself in lab. There is a learning curve to everything in life. There's nothing that doesn't have some sort of a learning curve. Um, you know, there's people like me who are still struggling with the remote control on Netflix. And there's other people who pick that up really fast, but there are learning curves to everything. So that's a challenge. What you'll find, though, is most of these are fairly easy to use once you get used to them, but you really do have to pay attention. Uh, arguably the most, um, unusual learning curve would be with the Hydrocolloid. For any of you who've worked with it, you might be familiar with this already. I see some nodding for those who haven't. The way it works is you take these tubes of it, you need a special kind of. Uh, I don't want to call it an oven. It's kind of a water bath thing. And you throw them in there, and they start out where it's kind of a solid gel inside the tubes, and it cooks them and make some flushable. And then you can put them in a special tray. You can temperature. And then you can put that special tray in the mouth. And you run cold water through it. You attach hoses. So is it easy to use. What's that? Yeah, yeah, yeah, some people still use them. And the thing about it is, is it easy to use? Once you get used to it, it's great. It's like tying your shoes. Once you learn to tie the shoes, it's pretty easy to do. Using those materials can be great once you start doing it, but it's a project and you know there is some specialized equipment involved. The other ones are fairly easy. The auto mix you're familiar with that. You've seen it in the clinic already. That's fairly easy. And yet at the same time when you well, you guys have done a lot of this, so it may not apply to you. But certainly when we see the D2 students in the clinic, when they go to make an impression, whether it's a scan or whether they're going to start to use the, um, like, say, PVS material, it's amazing how many times they could make an impression and have it not come out. Just because you're not comfortable with the material. You're not good at placing it where it needs to go. It takes a lot of practice, so there's a real learning curve with all of these things. Uh, good taste, good smell, looking good. All those things. Um, arguably the best of those. I mean, digital has no taste or smell, so that's fine. But of those other things, probably the PVS is best. The PVS is made to look good. It can be colored whatever the way they like. So most of the materials have nice bright colors. You know, they're bright blue or orange or green and they they look kind of nice. The PVS materials have no inherent taste, so they can be flavored so they can be made to taste good. Although most patients don't experience much taste because most of us it's about smell, and it's usually only once they've set. So by the time you're done it, it gets better. But then with the polyester, they you might like the smell or not, that's. But the taste is horrible. Poorly either. Tastes terrible. Bad taste. Good smell. Maybe not a good smell. It depends on each of us. You don't like it? Yeah, but it's. But the taste is awful. And with the hydrocolloid taste and smell, not a big deal. A lot of them are minty, sort of tasting. Yeah. Yeah. So but it's a, it's one of those sort of it's not a, you know, it's not bad. So in that way it's good. Now here was the thing that was kind of interesting that was brought up that question of set and what that means and what do we really want. And I said, well, what we might have in an imaginary material would be something where we, you know, load our tray, set it aside. We inject our material, seed our tray, make sure it's where we want it. And then, like I said, we say some magic words and pull it right out, which would be amazing. That would be great. And you would think that that doesn't exist, right? And yet the weird part is, it kind of does. But not really. All right. Let me explain. The way it kind of does is say if you stick with a family of materials like polyvinyl vaccines, you can get PVS materials that are going to set as fast as about 50s and as slow as about five minutes. So do you have that ability to seed it and say magic words and have it set? No, but you can use a facet material that you might put in the patient's mouth and pull back out in about two minutes and 15 seconds, which is if you're only doing 1 or 2 teeth. Maybe three teeth. Depends how fast you work. Is almost like saying magic words and popping it right out, as opposed to every time it has to be in there a long, long time. So is it possible to have controlled set? Not quite, but you can make choices of which materials you use in what. Sequence to sort of control the set. That's with PVS materials. The poly ethers offer varying setting times. Hydrocolloid is different. It's always the same thing. You always have to attach hoses that run cold water through the specialized trays that make it set. So it's always like a five minute set digital. There is no set. The speed of it is strictly how fast you can scan. Now you're going to take a whole course on, you know, on Serac and scanning and prepping and all that. You're going to take that course. Uh, I guess in the spring, in June. One of the things that I hope emphasizes ways you speed up scanning, the way you speed up scanning. Just to quickly go over that with the idea of controlled set is you do a lot of it when it doesn't matter. So what I mean by that is you sit your patient, you say working on a single unit 19. So you inject them, you're waiting for them to get numb. So what do you do while you're waiting? You take the scanner, scan that arch, scan the opposing arch, get the registration. Now that's just sitting there on the computer. You prep your tooth if you need retraction cord or whatever. You do that now you cut out. Essentially delete that little bit of the initial scan of 19. Come back, and now you're going to just scan that one tooth really quickly so you can it's not quite the same. As you know you can control all of it, but you can make it quick and easy. There's ways to succeed with it. If you if you pull your cord and try to scan the whole arch, you're going to struggle. But there's ways to make it. It go well and quick. So let's go through the rest of these quickly. Cheap? Uh, not so much. You're probably aware. Digital scans. Very expensive. Even the cheap ones. It's expensive to buy if you want to start adding, you know, milling units, it's even more expensive. So that's not so cheap. The individual impressions are very cheap once you've invested in it. Hydrocolloid is very cheap. Once you've invested in the hardware, very, very cheap. The other materials again have gotten cheaper. So PVS poly ethers have gotten to be much more manageable in terms of cost. But they used to be very expensive. Um, hydrophilic. Well, interestingly enough, Hydrocolloid by its name is hydrophilic. In fact, when you use Hydrocolloid, one of the things you do just before you're going to inject the light body material is use your air water syringe to spray the tooth. You want it wet? Um, digital. Quite the opposite. Any water that's present will be water you scan, so it has to be bone dry, or you're going to scan water, which isn't what you want to see with the other materials. They vary. They all claim to be somewhat hydrophilic. How hydrophilic they actually are varies in most cases. The surest way to get impressions, though, with the other elastic materials, is that you have a clear field that you can inject on. So if you like the idea of hydrophilic, there's really one choice that's a sure thing. All of them are adequately elastic. But when we talk about something that's very elastic, always easy to remove. They do vary. Of course digital doesn't matter. Hydrocolloid is going to always be a pretty elastic material, but it doesn't have a perfect tear strength. The other materials are going to vary. PVS materials tend to be pretty elastic, and if you're not using a heavy body, you're going to tend to pull out of the mouth pretty easily. They have this odd quality where they almost seem slippery or oily as you pull them out of the mouth. Poly ethers, for those of you who have used them, may have seen that their different poly ethers really stick in the mouth. For those of you who haven't done that type of impression before, the first time you do a full arch of gum in the clinic, be prepared. Whatever you think you have to do to pull it out, plan to pull it out twice as hard. It's very common for we'll see our students where they have a whole arch. They grab it, they give it a tug, and they're like, and they freak out because they think it's never going to come out of the mouth, because what you have to do is you have to grab it, and you have to really yank it out because it's really tight. The big thing with any of the elastic materials, though, is you have to be aware of things like patients who are periodontal compromised, patients who have a lot of space under contacts, you know, people, old patients with long teeth and a lot of gaps because that's where they can lock in the mouth. So you have to watch for that. As I said, tear resistance is an issue primarily with the Hydrocolloid because it doesn't have great tear resistance. The other materials much better. Um, and really where it shouldn't matter to us too much. Um, all of them are easy enough to read, except the hydrocolloid can be difficult for a lot of people because it is wet. It's kind of a glistening surface. Many people struggle to read it. The others should be easy. We talked already about how they auto mix. Um, then none of them have an infinite shelf life except your digital scans. But of course that doesn't either. You get a nice digital scanner, you spend a small fortune for it, like a half a year's tuition, right? It's close, it's expensive. And then what happens a year later? They say, hey, by the way, there's a software upgrade you need for this. And because you're a long time customer for the last year, we'll let you have it for only $5,000. And you're like, this isn't so cheap. And they're like, well, if you were buying it now, it'd be even more, you know, so even something like that, which has sort of an infinite shelf life. They're going to need upgrades. And at some point the scanner's antiquated. And now you're going, wow, I wonder how many of these pvz impressions I could have made the last five years without buying two new scanners? So, you know, things like that that seem self-evidently a bargain may or may not be. There's so many different factors that go into it. So they all they all have their costs associated with them. Uh, you can pour your digital scans obviously, because they're just digital. So you can make as many models as you'd ever like. That's easy. With the PVS and Hydrocolloid, they allow multiple pores. That's fine. The others, not none of them, are reusable except the digital scanner. If you sterilize it properly, you can reuse it as many times as you like the other materials? Unfortunately not, except the hydrocolloid a little bit. Remember I said, you take these tubes and you cook them well if you don't use them that day. Well, set them aside. Bring them back the next day. Cook them again and you can use it again. But after you've made an impression, it's really not reusable because that would be really disgusting and probably malpractice. Um, waiting to pour. We talked about with dimensional stability on a couple of those, uh, they're all we talked about this disinfecting, um, you know, the, the, uh, obviously the digital scanner, we know how we try to keep that clean and and can disinfect some of those PVS, um, in pregame, spray them, let them sit. That's fine. I know there are ways to disinfect hydrocolloid, but honestly, I don't know how they do it because you couldn't really just spray it because that would affect it. So you kind of need to port. Maybe they disinfect the casts, but um, let's see in terms of these, we use stock trays essentially in all of them, except that the hydrocolloid has its own kind of a stock trades, premade trays. All of them though, do need the correct adhesive, not the Hydrocolloid, but the PVS or gum have to have the correct adhesive. And that's really, really critical. It's one of those common mistakes we see in our clinic. So it's worth highlighting. If you don't have the correct, uh, adhesive, your impression probably won't fit the tray properly and it can distort. So that really actually does matter. And do we have anything else here. Oh we have well non staining uh frankly most of these materials will peel away pretty easily now. So they're not that bad. The final thing would be hemostatic that we have there. And on our list calling for hemostatic. Our problem is none of them are hemostatic. So none of them are going to displace tissue, because that's something that we've mentioned in the past when we've talked about ideal things. And digital doesn't help you if the patient's bleeding, if there's water there, all you're going to do is scan the blood or the water. If the tissue is not retracted, if you don't see your finish line, you're not going to scan your finish line. That's going to apply to all these materials. And so one of the things we're going to talk about next week is how do we manage tissue. How do we actually take impressions. Let me just do one last thing before we run out of here. Let me see if I can pull up. That's not what I wanted. Hold on. Uh, one last thing. Uh. Sludge show. Kidding. Um. SPEAKER 1 Let's see if we can. SPEAKER 0 I just want to. I have a summary of this kind of list that will glance at real quickly, just in case there's anything there we should be looking at. And then we'll be done. Any questions about this before we glance at our list? SPEAKER 1 All right. SPEAKER 0 All right. So for our impression materials, this was a list I had made up. And I think as we look at it, we're going to see most of it is going to be fairly. Let's go back. Most of it is the stuff we've already talked about. I'm not sure if there's anything here that we didn't discuss. Um. I don't know as you glance at this, but pretty much where does this leave us though, with our impression materials? Because we've talked about a lot of things. If we wanted, uh, materials, like, we had a list of things of the different materials that we talked about, the hydrocolloid, the polyvinyl selections, the poly ethers, and the digital scans. Which ones probably hit the most categories. Pvz hits a lot of categories. Digital scans, they hit a lot. How about the program? Did that hit a lot of it? Pretty much. Other than the bad taste, it gets most of it. So. Where we end up, which we probably knew this before we started. Where we end up is that, well, what what do we like best? Digital scans are going to cover most of our imagined goals for our impression materials. If we call digital scanner material, PVS is going to hit our goals pretty closely, not perfectly. And frankly, poly ether hits a lot of our goals pretty closely. So when you get to the clinic, what are you going to find? You're going to find scanners. You're going to find PVS. You're goin