Injection Molded Class II Restorations with Heated Composite: It's a Game Changer

You're listening to The Dr. Phil Klein Dental Podcast from Viva Learning.com. Welcome to the show. I'm Dr. Phil Klein. Today we'll be discussing the use and benefits of heated composite on injection molded Class II restorations. Our guest is Dr. Joshua Solomon, a second-generation dentist who has been in practice in California for 20 years. Before we get started, I would like to mention that Dr. Solomon's webinar titled Confidence with Injection Molded Class II Restorations with Heated Composite is now available as an on-demand webinar on VivaLearning.com. There are some amazing clinical videos in that webinar, so if you're interested in learning how to do an Injection Molded Class II, check it out. Simply type in the search field Solomon, S-O-L-O-M-O-N, and you'll see the webinar. It's an excellent webinar for every dental team member to watch. Dr. Solomon, it's a pleasure to have you on Dental Talk. Phil, thank you so much for inviting me on. Yes. As I mentioned in my introduction, you did a fantastic job with that webinar. A lot of it was, I guess, filmed live with an overhead camera that we streamed to our audience. We had about 900 people on that webinar, and I did mention it in the intro. And what I loved about it is there was a lot of clinical video in there. It was on deniforms, but it really showed with the matrix band, with the wedge, the whole process of using heated composite and this injection molding technique. So to begin this podcast, let me ask you this question. What are the advantages of using heated composite? And while you answer that, tell us if there are any disadvantages. Sure. Dentistry has gotten difficult today, right? You know, it's... along with COVID and insurance reimbursements, and it's just more difficult. I've been a dentist for 20 years, and anything that I can do today to make my restorative care faster, safer, and more predictable at the end of the day, that's always my goal. The beauty of using warm composite, first and foremost, is changing that extrusion pressure. I've been using warm composites now for at least six years. And, you know, if you hand me a compule of room temperature composite, I just I don't even know what to do with it anymore. So first things first is changing that that extrusion pressure. So as we warm composite, we know composites of viscous material. Right. So as you warm composite and you have to be careful on which composites you're using. And, you know, we'll touch on that later on on the podcast. But. when you warm a composite you take that viscous material it changes the viscosity of that resin and we know that when you heat a viscous material the extrusion pressure reduces so with a compule of composite it's about 70 percent more flowable and your flowable itself is about 50%. So when we use something like the injection molding technique or injection over molding technique that I showed in the microscope live, it allows us to wrap our restorations around teeth. You know, in dental school, I was taught you drill a hole in the tooth and you fill that hole. But the difference with... using warm composite injection molding technique is fillings now go around the tooth instead of in the tooth. You only can do that using warm composite with pressure. Yeah, you made a good point in the webinar about how in dental school they wanted you to end the margin in an area where it's the most difficult to clean. And, you know, nobody asked that question when I went to dental school. I wish they did because that would have been an interesting one to ask our instructor. Like, why are we doing this? We're literally putting the margin of this incredibly difficult box that we're creating in between the teeth in an area where the patient most likely cannot get to, which is the most vulnerable part of the whole restoration when you're doing direct. Well, that was amalgam back then, but when you're doing direct composites. So let me ask you this about warm composites, and we'll get to the fact that you have this circumferential margin. It's like the infinity margin or however you refer to it in your webinar. As far as the disadvantages, is it dangerous to the pulp? I mean, I guess if you do it properly, it's not, but is there room for an operator to heat up that composite where it causes a pulpitis? Great question. So, you know, first... adding another piece of equipment it adds to your clinical materials that you need need to have and you know the good thing is is there are several manufacturers that make composite warmers the things that i look for and the reason why i use the bio clear heat sink is it will keep our composite at a steady temperature we shoot for that we want that composite about 155 degrees fahrenheit and the door on the top of the BioClear heat sink allows us to keep that steady temperature with the composite. Number two is it's got to be cleansable. You know, this is a piece of electronics, right? So you need to be able to take the warmer apart to be able to clean it, to be able to sterilize it. And I'm able to do that with the BioClear heat sink. Yeah. Could you just clarify one thing, Dr. Solomon? So BioClear and 3M. work together on this right and that's something that's important to know because otherwise it's not going to be clear when we talk about these companies can you just clarify to our audience what that is what that's about absolutely so if we talk about bio clear as a matrix company right we also talk about the bio clear method when we introduce these things like preparation designs and injection molding and polishing but when we talk about the bio clear matrices themselves These are HD mylar, so 75 micron mylar, that instead of calling it a matrix, I really like to call it an anatomic tooth form. It's the first time that I've ever had, specifically in the posterior, let's say, a matrix that's actually shaped like the bicuspid or a matrix that's actually shaped like a molar. And so it's a system where we have the twin ring, we have the diamond wedge, and then we have these anatomically correct matrices you can actually clear through. And these matrices are prefabricated straight out of a box? prefabricated straight out of a box. We do some trimming. And as you get comfortable with the technique and the materials, you know, once in a while, trim matrices a little bit to allow it to, you know, seat subgingivally or, you know, to pass a rubber dam or rubber dam clamp. But these are out of the box. We pick the matrix based on the location and the shape of that tooth. Right. And that's why it's called injection molded, right? Because what you're doing is you're taking this plastic and you're putting it on the tooth and it's open on the occlusal. That's where you inject into, and you're just literally squirting this stuff in, as you did in the webinar. And it wraps itself around the interproximal area from the base of your box all the way around to where you can actually get to it to clean. You could even brush it with a toothbrush once it polymerizes. You call it an infinity margin? That's it. So we talk about the tooth restoration interface, the TRI. And that's an infinity margin. So the way when I teach courses, I like students, doctors to think about, you know, if you've ever troweled drywall and you put mud on the wall when you're doing drywalls, you start with a material that you can spread evenly and thin those layers out. And so I cringe a little bit every time I hear the word margin, because what we know about composite, composite doesn't like to be marginated. Even if you look at 3Ms. guide, their insert guide, it says to overfill the cavity preparation slightly and polish that back. So the goal with injection molding is to move that quote -unquote margin to a self-cleansable area. It never made sense to me in dental school why I've got a tooth with a hole in it and the patient couldn't keep it clean in that interproximal area in the first place. And now I'm going to take, as you mentioned, you know, the most tenuous part of that restoration and I'm going to put it in the exact same place the patient couldn't keep it clean. How do we adapt? to this with our tooth prep, a typical DO, a number 30, what do we do to the axial wall, the margin? I hate to use the word margin, but just so we all understand, the traditional margin that extends towards the buckle, even though it's into proximal, there's still something coming to the buckle and something going to the lingual. How is that different now with this new infinity technique? That's a great question. This is something, it's one of my favorite things to talk about. First and foremost, this isn't something that's new. There are five dental schools in the U.S. and Canada now that are just teaching the Clark Class II restoration and preparation. And so this is becoming, in many circles, just the way that we prepare teeth. Most importantly, we forget that each square millimeter of Denton has 10 000 dentinal tubules in it and you wonder why we have this epidemic of sensitivity and composites especially in the posterior the thing about the clark class 2 preparation itself is we are maximizing enamel engagement and we are minimizing detinal engagement or dentin bonding i in my head i'm shooting for 70 30. i want to wrap that restoration all the way around the buckle and lingual and many of my restorations are somewhere midpoint around that buckle and the meso or bicuspid sometimes it'll wrap almost all the way to to the other contact we are moving that infinity edge that tooth restoration interface to engage as much enamel as possible number one and number two to put it in a in a place where the patient can keep that clean and what also comes along with that is we know that composite shrink i don't care if you're using a bulk fill composite all composites have some level of shrink to them correct when we hit that with the light right so we can actually take advantage of some shrinkage stress by having a preparation where when we come to the cable surface i'm thinking about 120 130 degrees of that radius bevel to number one take that shrinkage stress and completely move that away from just the dentin we're not prepping teeth like we did with gb black in the 1800s dental school most dental schools they're still teaching gb black right parallel walls and every time you you put that light on the tooth if you've got a parallel wall with high c factor those walls tick tick tick they start moving in and that's where we have one of the main reasons why we get sensitivity with these composites especially in the posterior Now, what happens if a dentist says to you, Dr. Solomon, I love the idea, but as we move to the buccal and lingual on that infinity prep, we're getting very thin with the composite. Someone bites into something in a weird way and it fractures, that could jeopardize the whole prep or the whole restoration, I should say. So that's a phenomenal question. First step. with the bio clear method is always disclosing the tooth so disclosing solution goes on and before we put that matrix on the very last step is we take a bio clear blaster which is aluminum trihydroxide and we remove all of the biofilm those proteoglycans that protein pellicle we know that there is no minimum thickness needed of composite over clean and blasted enamel now if it's a custom different story we need a couple millimeters there but as in approximately move around those buccal lingual areas the key is we've got to have clean and blasted enamel if you don't that's flash if you do if you completely clean that tooth surface you prepare it for bonding there's no minimum thickness of enamel and you don't have to worry about is my restoration becoming too thin that's what we want i want that infinity margin i want that tooth restoration interface So what's the armamentarium that a dentist needs to get started? You know, and I don't want this to be a commercial plug for any particular company, but this is a very unique technique in a sense that it's not prevalent in every office. Most of the doctors are doing what they did in dental school, the GV black stuff. So what do we need as far as you need a clear matrix? And if you could tell us what that is. what company it is, and what are you typically using for your direct restorative? So let's take the posterior, for example. I'm going to place a MO on tooth number three. Number one, it's going to start with disclosing solution. BioClear sells their own disclosing solution. You can use a disclosing solution you may already have in your office. That always goes on first. Secondarily, we're going to put a diamond wedge in. key differences with a diamond wedge with BioClear number one is the spine height from the small wedge all the way up to the extra large is the same height that's where a lot of dentists run into problems they take a small wedge and they go up to a large the spine height of that wedge increases in height and that's why we often have these kissy contacts in the occlusal third of the tooth so we have a wedge that's actually will spread out broad and help oppose our matrix against the tooth but not change the contact point we have a matrix that's actually shaped like the tooth again these are really anatomic tooth forms i'm going to pick a matrix that is basically an analog to the tooth itself i want my matrix to look like the tooth because it's really my diagnostic wax up if my matrix is properly sized after injection mold after i cure i'm going to take that off and i have almost no finishing polishing to do we saw that you know under the the microscope under the live video is i'll spend more time making sure my matrix is perfect my wedge is perfect my twin ring goes on which is you know two layers of tubular niti we need definitely more separation pressure because the mylar is you know it's it's slightly thicker than some of the metal matrices but that system allows me to actually not oppose the matrix completely against the tooth it does in the cervical areas but i want to have that laminar flow of material and we use adhesive flowable and paste so that's the other part of this is the matrix that's shaped like the tooth a wedge that properly fills that embrasure a ring to help with our separation pressure that does not seal the matrix against the tooth and then we're using an adhesive in the 3m system so in the posterior we're using 3m fill tech bulk fill flowable along with scotch bond universal plus so the adhesive goes down then the flowable and then what we call the paste which is the compules of the philtek one bulk fill the flowable is heated also the flowable is heated so the the bonding agent of course is room temperature but the bonding agent we after we cure the dentin we're going to put another layer of bonding agent in and it's acting just as a wetting agent and disinfectant air thin then warm flowable goes in the tooth and then we use the compule which we call paste and what we're actually doing is we're pushing out almost all of that adhesive almost all of that flowable is acting as surfactant so what we have left is this monolithic restoration that's engaging as much enamel as possible and minimizing the amount of dentin that's engaged yeah so the actual matrix is made by a company called bio clear correct so the BioClear system has the heat sink, which I use to heat the composite itself. And then we're using, getting back to your question, we're using 3M restorative materials. What about the wedge itself? What is that? The wedge evolves from BioClear. So in the BioClear universe, our restorative materials are all coming from 3M. And then BioClear itself has the matrices and the wedges and the rings and the warmer and the polishing system. and then most importantly is the very first step right before that matrix goes on is using the blaster remove any biofilm that's on the tooth my basic steps are after my matrix wedge and ring are in place i'm going to etch rinse and dry then we take our and scrub it into the Denton for 20 seconds. And that's one thing that sometimes people skimp on. You really need to scrub that adhesive into the Denton for 20 seconds. We'll air thin. Now, if needed, we may add a little, we call them spot welds, which is around the periphery of the matrix. And you saw this in the video, we add a little bit of flowable. And then we will, when we cure that adhesive or the Denton, we'll use an instrument to help oppose the matrix against the adjacent tooth. then we like care. Right. And now I've got a perfect system. Dr. Solomon, I really appreciate your time today. Great stuff. I'm glad we could augment that great webinar with a podcast. And hopefully we can drive some of our listeners to the webinar where they can actually see it visually versus listening to it. And, you know, there's nothing like trying it. You got to try it to see if it works for you. Right. Absolutely. You know, and there are more resources online. If you go to BioClearMatrix.com, you'll see some other videos and information as well. Excellent. Thanks again, Dr. Solomon. Have a great evening. You as well. Thank you, Phil.