Occlusion on Class IV Composite Restorations – PDP150

What should the occlusion look like when you are restoring or replacing a Class IV restoration? This question is so basic yet so complex which is often not talked about enough. We go on all these composite courses and talk about the layering, but we don’t talk enough about how to put the principles of occlusion into action.

In this episode, Dr. Ibrahim will be talking about how Class IV Restorations can be optimised to get a long term predictable result. We also shared the two mechanical failures in dentistry and the step-by-step process of a Class IV restoration with occlusion in mind.

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The Protrusive Dental Pearl: Occlusion Whisperer – Ask your patient to bite together and listen – in a “good” occlusion you should hear lots of tooth-to-tooth contact, whereas a thud indicates an issue. Use this in addition to more traditional methods of assessing the occlusion, and make sure you are satisfied with the occlusion before asking the patient “how does that feel?”

Are you ready to learn Occlusion in a way that makes sense, in your own time, with first class support and career boosting confidence to deliver Restorative Dentistry to the highest standard?

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Need to Read it? Check out the Full Episode Transcript below!

Highlights of this episode:

00:49 The Protrusive Dental Pearl
02:23 Dr. Mahmoud Ibrahim
03:07 Class IV Lesions
07:21 Mechanical Failure
09:28 The “Envelope of Function” and “Chewing Space”
13:50 Dealing with Limited Chewing Space
17:49 Mock-Ups
19:35 Dots and Lines
21:14 The Process

If you enjoyed this episode, check this another episode by Dr. Mahmoud Ibrahim, Next Level Occlusion (Basics Part 2).

Click below for full episode transcript:

Jaz's Introduction: What should the occlusion look like when you're restoring or replacing a Class IV Restoration? It's a really interesting question actually. Like it's so basic, yet so complex.

Jaz’s Introduction:
So we’re going to make this topic, which is often not talked about enough, and like we’ve got all these composite courses and they talk about the layering. But we don’t talk enough about how to put the PRINCIPLES of OCCLUSION into action on your Class IV Restorations to actually get a long-term predictable result.

Hello, Protruserati. I’m Jaz Gulati, and welcome back to PDP150. We’ve got over 200 episodes of Protrusive now with you, include the Interference Cast, and all the other branches of the podcast that we do. Thank you so much for joining me time and time again. If you’re new to the podcast, welcome. You picked a really interesting and fun topic to join us on today.

Protrusive Dental Pearl:
Now every episode I give you a Protrusive Dental Pearl. And of course it’s going to have to be an occlusion one. Okay, so this is something I learned in my time at GUYS Hospital when I was at DCT.

This was like nine years ago now. And it is when you’re checking the bite, do you listen to the bite? Now it sounds really funny, but we check tactile, we check with the shim stock foil or the articulating paper. We check visually because we see the ink marks on the teeth. We could check with our fingers.

When you bite together, you feel some pressure, feel some vibrations on the teeth. These are all methods of checking. The occlusion is something proud, is it not? But sometimes a really good thing that I like to do routinely after restorations is just listening to the bite. I tell my patients, I’m the occlusion whisperer.

Okay? So I come up by their teeth and I say, ‘can you tap your teeth together like this?’ And that’s what a good occlusion sounds like. Okay. Lots of teeth hitting together at once. If there’s a thud, then you know that you are proud basically. And this is a really good additional tool that you can use.

The very last piece of information that you gained from the patient is, how does it feel? That’s not the first thing. Usually we are guilty of doing our restoration and saying, we are usually guilty of restoring the tooth. Then asking the patient straight away, how does that feel in the bite where really we should do all our checks, make sure we are satisfied, and then the very last piece of information we collect is, how does that FEEL?

Because remember, that’s subjective. Whereas if you are using objective data, then that’s much better. Often helps if you listen to the bite beforehand if you are new to doing this.

Main Episode:
Anyway, let’s join Dr. Mahmoud Ibrahim and I’ll catch you in the outro. Mahmoud Ibrahim, my occlusion brother from another mother. Welcome back to the show, man. How you doing?

Yeah, I’m good, man. I’m good. Thanks for having me again.

Dude, I’m so pumped because now obviously OBAB was launched. It was the most difficult year of our lives and I think we’ve talked about that already, so we won’t bore everyone about that. But today it’s a really cool occlusion topic that Dr. Humer on the app sent in.

So, on protrusive.app, on your browser. Or on iOS, Android, there’s a community section within the app. And Humer who’s actually a delegate of OBAB, actually she’s a delegate of OBAB. Yeah. But she’s done a few with the first module and she’s like, actually, I’ve got a question.

Maybe you cover it later in the course, but I just want to know, and she asked basically and I’m going to get up the actual full question. Okay. So Houma said, ‘Hey, Jaz, I’m enjoying OBAB so far, but my question, which I’m sure you’ll probably answer in the next few episodes, when restoring Class IV Lesions, okay, so Class IV guys is something that involves incisal edge and the facial often, and the palatal.

So a fair chunk of an incisor, an anterior tooth could be an upper or lower. For example, you check the occlusion beforehand, dynamic and lateral excursion, what is our aim in order to avoid early occlusal failure? What shall I actually look out for when checking the occlusion once the restoration is complete?’

And so Mahmoud, this question, it could almost be like an essay question in a dental exam, because it’s not like a one or two word answer. You can literally philosophize and debate, which is what we’re going to do today, in the next 26 and a half minutes.

And I got pumped and I wrote a little answer for little, it was a little bit longer than little, and then you wrote an answer and we thought, okay, this would make a really fun, fun for me and you, podcast episode about what should the occlusion look like on a Class IV Composite Restoration? So I guess where do we begin? And I think the where to begin is, I thought Mahmoud, like what is the reason for actually replacing that Class IV incisor, right?

Yeah. I mean, so ultimately, it’s actually a fantastic question because we all know occlusion courses tend to go on about full mouth rehabs and stuff like that, but this is the nitty gritty that we all do day in, day out-

And no one talks about this. No one talk, even on the composite course I’ve been on, they show us how to layer. It’s so crazy. Actually, they showed us how to layer the Class IV, use 17 different shades and tints, but no one actually said what the dots and lines should look like.

Exactly. So this beautiful layer of composite is going to break off because you haven’t paid attention to the occlusion. So it’s a fantastic question. And what I love about the question is that she’s already mentioned the fact that she’s going to check the occlusion beforehand because I think that’s where you need to start.

That also is never talked about. You can’t check the occlusion afterwards if you don’t know what the existing inclusion is. So it’s good to at least initially, let’s say we’re going to be doing this Class IV, because there is caries, there’s a trauma fracture existing. Class IV has failed. Maybe just aesthetically stained-

But let’s talk about that Mahmoud one second on, there’s so many different facets of all the different reasons why you might do a Class IV Composite Restoration. But, the easiest one, maybe just to tackle straight off the bat and just tick off is the one that’s been there for 17 years and it was used to be an A1 and now it looks like an A6, right? And otherwise it looks completely unworn. The composites, it looks good still, the shape is good. The patient’s happy with the shape. It’s just the shade you want to change. And if that composite in that mouth has survived all those years, then the answer is very simple.

Whatever the dots and lines look like beforehand, you just completely replicate it and that’s why you make your putty and you change it over. So that’s the easy one to tick off. And I guess the other easy one we can just really quickly tick off before we get to the more complicated ones is if your patient has an anterior open bite.

You could even make a 3D composite initial of your name on that composite, and it’ll still be okay because a patient has an anterior open bite. Okay? So patient’s not occluding functionally or para functionally on that Class IV. So I’m not saying do that because it’ll feel strange to their tongue and stuff.

So really with with AOB cases and you’re not doing anything about the anterior open bite, then you can get away with anything and just pretty much copy what’s there before. Or roughly follow the contours or what an incisor should look like. But the main lesson is if the composites has been working well and it’s an aesthetic failure, then copy all the good features and just change the aesthetics.

Okay. So those are the easy ones. Now, the more difficult ones are the ones that the patient has walked in either with a fracture or an existing composite that’s come off, especially the ones that the patient walks in and he says, this is the third time this has come off in a year or whatever.

Those are the ones where you got to be careful and start thinking about why has it come off? Why do we now need to start thinking maybe slightly differently? But yeah. I was just going to say, one important thing to say is that at the moment we’re conforming to the existing occlusion. Okay? So when you’re just doing a single Class IV on a patient, you’re not going to be changing the rest of their bite.

You’re going to conform to the existing occlusion. Now, as we say, as well in OBAB, doesn’t mean we’re going to blindly copy what’s there. Sometimes we can idealize the situation and sometimes the reason it’s failing is cuz no one’s bothered to look at what the occlusion is doing to it and idealize it.

Absolutely. And this is a good point, maybe Mahmoud to mention as something I talk about which a lot of the stuff I talk about is completely stolen and borrowed and regurgitated because I’ve learned so much from my mentors and I pass it on to you guys on the podcast, listening and watching right now.

So, very few bits of what I say is original, and I’m happy to say that. This bit I think is my own thinking. Maybe everyone’s thought it, but the whole thing about there’s only two types of mechanical failure in dentistry. That’s it. There’s tooth to tooth. And tooth to something else. So assuming the tooth to something else bit is something you educate your patient.

It’s out of your control, but you educate your patient. So what I mean by tooth to something else is tooth to fingernail. Yeah? The fingernail will win. Tooth to sellotape being cut between your front teeth, tooth to ice. I made an Instagram reel recently. I mean, we might have seen it. Okay, so ice chewers are dangerous.

Crazy people. Okay? So you need to inform them. Even if you’ve got like a resin bonded bridge or quite a fragile, large Class IV composite, you do not want your patient to bite on their crusty pizza or baguette directly on that tooth and tear it or corn on the cob. Another dangerous thing to attack with your bridge or a adhesive restoration, right?

So assuming the tooth to something else, you’ve educated your patient. The only other cause of mechanic failure is tooth to tooth. And so when we talk about tooth to tooth, we can branch it into two different things. There is functional failure and then there’s parafunctional failure.

Exactly. So the way you want to check whether you think the patient’s occlusion is pathologic or physiologic. So we’re going to look at the rest of the dentition. You can’t really just look at one tooth, you’re going to look at the patients, the rest of their teeth. Is there signs of wear, cracking, fracture on the other teeth? If there is, you know, the patient’s doing something weird. They’re grinding teeth. They’re doing something that they shouldn’t.

It’s a parafunctional movement. And then when we talk about, I believe you had a whole episode on constricted envelopes, constricted chewing pattern envelopes. So again, if the envelope of function isn’t respected, you’re going to have excessive forces, especially on the upper incisors, and that can lead to early failure of your restoration.

Let’s break that down, Mahmoud. Okay. As someone who might have never heard of OBAB before, never heard, never seen our previous episodes on occlusion, which we haven’t actually talked about the envelope of function so much in our previous episodes. We really boiled down even more fundamental than that. But what is the Envelope of Function? Let’s just talk about that in a moment.

Okay. So essentially the way we chew isn’t just down to your teeth. So you’ve got your neuro muscular system, your muscles fire in a particular way. You’ve got ligaments that are particular length, the bones of the jaw, particular length.

So the jaw has essentially this pattern of movement. This what we call sort of on OBAB I call it the ‘mandibular swing’. Okay? So once the swing in a particular way. Now if their teeth happened to be in the way of how the muscles want to move the jaw, you could accidentally be bumping into these teeth a bit more than you should, so you’re adding extra force onto the teeth.

But essentially the envelope of function is that movement that the mandible wants to do when you are chewing a sandwich, when you are speaking, when you’re swallowing, et cetera. So that’s sort of built in and what you want to do is not put stuff in the way of how the mandible wants to move.

I like to call the envelope of function, the ‘chewing space’. The worst, I mean, the patient we can think of, which has got trouble written all over it is, the patient who’s almost edge to edge Class III, but not quite. So maybe they have like, one millimeter overjet, like the lower incisors are right up against the palatal of the upper incisor. Okay? So when this patient is chewing, they don’t have much chewing space.

So as they make that teardrop shape anteriorly, if you trace the movement, it’s just classically a teardrop, right? And so as they open, they come forward, the mandibular swing, and then they come back. And what we have here is a high frequency, low intensity, because functional force are lower than parafunctional, but they’re still 30, 40% of your maximum force.

They’re still decent. So if you’re constantly chewing, chewing, chewing during the day, during from eating and all the other functional things that we do, every time you swallow your teeth comes together and they’re constantly bashing, then something is going to happen. Either teeth will wear, teeth will chip, teeth will migrate. Right.

Mobility and movement over time. And that depends on the patient’s own genetic and biological, I guess the weakest link factors, which is something else we talk about. But envelope function is a chewing space. And so the classically, if you have this patient, just like you said, who’s broken their Class IV Composite three times in a year, and you’ve looked everywhere else and you think that, okay, there aren’t many cracks and there aren’t much signs or parafunctional grinding.

You got to look, how much overjet do we have? Is it potentially a restricted envelope or a constricted envelope, or a frictional chewing pattern? All these things we’ve talked about before. But essentially it boils down to there is not enough chewing space.

Yeah. And the only way you’re going to pick that up is if you look, I mean, I’ll admit too, in the first few years of practicing, sometimes I’ve restored a tooth and then got the patient to bite, and then realized that, okay.

There’s just no room for my restoration. Or even more embarrassingly, there’s no opposing teeth. You’re getting the patient to check the occlusion and there’s no opposing teeth. So really it’s about checking beforehand. And we talk a lot about checking for fremitus as well.

So even though physically you might look and there might be space for your restoration, it’s very important. So what fremitus is, is when you take your finger, then you put it so on the facial surface of a, say an upper incisor. And you get the patient to tap their back teeth together, you’re just getting them to bite into MIP just asking them to tap, tap, tap.

So what you’re checking for is you’re seeing whether you can feel that tooth sort of vibrate and sort of get pushed out a little bit as the patient taps together. If that’s the case, it might indicate that actually there’s just a little bit too much force on that tooth. So maybe it’s in the way of how the mandible wants the bite together.

You also want to check fremitus for when the patient grinds forward, grinds side to side. Again, you want to feel, is that tooth being pushed out as the patient’s grinding? Again, is that tooth taking a bit too much of the load when the patient grinds side to side? That’s sort of my preferred way of checking the envelope of function.

I think you also talk about doing the dinner plate test, which is something we show, but that’s really, really important and something that’s not really told very well. And you want to check that with the patient sitting up as well as lying down. Cause we don’t usually chew when we’re lying down.

Exactly. And so when you’re doing these functional checks, it’s sitting up when you’re doing the para functional checks, it might be when the patient’s laying down, you’re completely right. Now let’s talk about the, just finish off this chapter of is there enough chewing space? Let’s assume there is not enough chewing space and you’ve come to the conclusion and then you’re going to now communicate this to the patient and you’re going to get your hands out.

You’re going to show them what’s happening, you’re going to take some photos. Ideally, we know the answer is orthodontics, right? To create some overjet and that kind of stuff. Create some overjet, create some chewing space, and then we can restore the case. But let’s talk about some cheat codes. Let’s talk about some ways that perhaps we could do it.

Now, some of these are kind of regarded as naughty ways of doing it, but if the patient’s point blank, not going to have orthodontics and you got to stick something there, maybe they’re getting married tomorrow, then what can you do to make sure that by the time they walk through the door, this composite’s going to survive? So, any tips you can give us?

Survive the honeymoon. You going to put the Robin Hood analogy. So, one way is look at the opposing teeth. A lot of the time in these constricted envelope cases, because the teeth have been sort of rubbing over time, not only have you chipped the upper composite, but that lower tooth had this like sharpened edge, this sort of angular wear on the facial.

You end up with a very thin edge, which then chips and leaves like these little short bits of enamel stick in it. So you can do yourself and the patient a favor. And just adjust those. You’re creating a little bit of space by taking away a little bit from the lower, giving it to the upper as per your Robinhood analogy.

So that’s one way to do it. And then, I mean, already we said that the ideal is ortho, but if they’re not going to do that, if you can’t take away from the lower. Then really you’re the only other option is you’re going to have to create room by repositioning the mandible, by opening the bite, but then you’re into far more complicated territory.

So the cheat code is look at those lower incisors and see whether you can maybe do a little bit of enamel plasty. I usually tell the patients I’m going to manicure your lower teeth, tends to leave them nice and smooth and they like it.

And I think getting the mirror out and showing the patient and getting your probe and saying, look, can you see that this lower tooth is sticky outy and your upper tooth is sticky in? Right? And they get that. Usually it is the way, right. They can see that there’s no. Chewing space.

And they say that, okay, if you know you’re getting married tomorrow or whatever, and ideally, and you need to plant that seed, ideally it’d be really good if we can just bring this upper tooth out and bring this lower tooth back in so that everything is going to be nice and straight.

You’ll have a beautiful, healthy smile and these filling will actually not keep breaking. This is why it’s been breaking. Mrs. Smith, can you see this? Can you see that it’s getting in the way and that’s powerful for patients. So then what you to then get is consent for, look, the only way I can resolve this now for you and make sure it survives your honeymoon is I’m going to tickle, I’m going to manicure the lower front tooth just a tiny bit with this little disc, just mostly to get rid of any sharp, annoying bits.

And then what you would also do perhaps in the upper opposite is, and this you show that you demonstrate is beautifully on the course is bringing out the composite, a little bit more labially so you want to bring it a little bit more labially. Now this has other nuances like, okay, are you now going from a Class IV?

Are you now veneering it at the same time? Because you need to have enough thickness because if you make it too labial, you’re going to have too thin of an edge, so you need to then beef it up labially and then it becomes from a Composite Class IV, it comes a class IV Stroke, Composite Veneer. And sometimes that might be the right way to go if the patient’s not going to have ortho, I guess.

Yeah, I mean, probably one of the biggest reasons for failure in Class IV Composites is not leaving enough thickness of composite. You want it to be at least a millimeter thick buccal lingually, especially on the edge.

Bringing it out facially does have some aesthetic implications, especially if you’re just doing the one tooth, but it’s usually better than not having anything there at all. And if you are on a strict timeframe, a lot of people would rather just have a front tooth, even if it is maybe slightly, you’re not talking like half a millimeter labial, or you can do a mockup, show the patient.

And say, look, this is if I can’t make it look like this, it’s just not going to work. With the adjustment of the lower tooth. And then they have to make a decision ultimately. Ortho’s usually the best idea, but sometimes we’re stuck and we have to deal with the situation we’re giving.

With mockups what I like to do is use a, I have got a whole stash of expired composite. Listen, if anyone around the world has got some expired composite, post it to me. I’ll give you my address. Just send it. I use a ton of that stuff, right? And certain samples I go to like dentistry shows and stuff, and I just click all these composite samples I’ll never use, but I use it for my mockups, right?

So you put it there, you use the ‘optrathumb’ and you get it looking as you want to, right? And then once you cure it again, this is no etch, no bond. The most common question I get when I talk about this ahead. Do you etch it? Do you bond it first? No. You don’t need to etch it, bond it just get a nice dry tooth and put it on, sculpt it.

I love to use my KC3C instrument, which you’ve seen me talk about before. And I get roughly the shape, which I think will respect the chewing space, but also get decent aesthetics. I cure it and now can check the occlusion. And make sure and I can even get a rugby ball, diamond bur and adjust this composite and adjust the lower tooth if appropriate.

And then now I can take a putty of this scenario. Now, even though in this perhaps emergency appointment, I’m not layering, I do actually do 99% of my dentistry one shade wonder. I’m a one shade wonder kind of guy, right? I know you are very skilled at layering and stuff. I’m a one shade wonder kind of guy, so I’ll just stick in the one shade.

It’s all we need exactly. Now, even though I’m not layering the benefit of the putty is that I can just whack it on, do my etching bonding, whack it on, and just get plenty of paste on there and just sculpt it and not have to worry about the occlusion afterwards. It’s just polishing afterwards.

Yeah, and that’s what you should be doing as well. If say, the other scenario you’re talking about where we’re replacing a Class IV, that’s just cosmetically failing. Everything else is fine. You’ve got all the data that you need. For the occlusion, everything right there. So I think it’s an underused technique really doing mock-up takes. I’m in it, five minutes if you’re just starting out.

Okay, Mahmoud, let’s now talk about the final bits, the technical bits, right? Let’s talk about the dots and lines. I know you’re going to talk us through a little step by step, which will really make it tangible. But as a quick tip here is if you’ve got, let’s say, two dots on an upper center incisor from your lower incisors, right?

And I’m okay for a dot be on my Class IV Composite, but if for some reason it’s a very fragile composite, then I’ll make sure that dot is a lighter dot or no dot. Okay. As long as there is another dot on there. And then now we got to talk about something really important is that if the patient had an incomplete overbite i.e. there were no dots, the front teeth weren’t touching, then that’s fine.

That makes your job a lot easier in terms of dots. But if they started off with some dots, it’s good practice to have a dot still. So if you’ve got a couple of dots, one on the composite, one on your enamel where the tooth is unrestored, then the dot on the composite on tap, tap, tap will be a little bit lighter.

So maybe the, the dot on the enamel will hold shim. Shim is eight microns. We use it, check the occlusion, and the dot on the composite will pull, just pull shim so it’s lighter. So that’s good practice. And then if it’s a really fragile composite, we check for protrusive and excursion left and right, and often you are going to accept having a line on your remaining enamel, but maybe the line on the composite will be much lighter again, because remember, what we are doing is we’re sticking a piece of plastic to some tooth that’s going to be subject to sheer forces.

So really it can’t do as much work as what your natural tooth can do. But what I’ma let you do now is, talk about the step by step of actually getting to that scenario.

Yeah. So as the person who asked the question said, I’m going to check the occlusion beforehand. So that’s where we start.

Okay. So we’ll go through this in detail on OBAB, but essentially you want to make a record of what the existing occlusion is. So we’re going to check that the patient has a repeatable MIP, right? We’re going to check, just get them to bite together and just have a look. That’ll also tell you if you have space for your restoration, is there a constricted envelope?

Has the tooth over erupted? If the Class IV been there a long time, I used to check you’ve got space, not just in MIP. Get them to grind as well and see if the lower tooth then passes through the area where your composite’s going to be. Because if that happens and you put composite there, if the patient has happens to grind that pattern, They’re going to knock your composite off.

Okay? So this is especially important if you’re doing edge bonding, you’re doing composite veneers, always check the excursions. Where am I going to put the composite? Is it going to be in the way of those lower incisors, like you’ve already said? We’re going to check shim stock holds. Okay? So I’ll check the tooth I’m working on and I’ll check the few on either side as well.

Document the teeth that holds shim stock and the teeth that drags shim stock. So we talk about, put the shim stock in between the teeth, get the patient to close, squeeze, and you pull on the shim stock in that. If it slides out with a little bit of resistance, that’s a drag. If it slides out with no resistance, that’s a no hold. If you can’t pull it out or you tear it, that’s a hold. So document those.

All you have to do is just tell the nurse, right, you’re doing this and you educate your nurse. This is shim. I use it to precisely check the bite. And then you are just speaking out loud while the nurse is now going to be trained to record shim holds colon, these certain teeth shim drags certain teeth. And then the rest of teeth will assume to have no hold.

Yeah, exactly. You don’t have to do the whole mouth, I’ll just do the tooth I’m working on and couple of teeth, and I decide. It’s really all you need when you’re doing one tooth. Okay. Once we’ve done that, then we want to check the fremitus.

So again, finger on the tooth you’re going to restore. And maybe the one next to it is on just get the patient to tap, tap, tap. Can you feel a vibration? If you can, again, you’re just telling the nurse fremitus positive, upper right one, upper right central, upper left central. But you’re checking the fremitus with, they have this Class IV cavity there, right?

They haven’t got their composite, so your job is now, so checking their fremitus but really what information that’s giving you is their fremitus with the situation they’re in at the moment, there might not be fremitus, but when you now put your composite later, then that’s the reason you’re doing it. You’ve got a baseline recording, right?

Correct. Yeah. Think about it this way. If there is fremitus already without you having restored the tooth, and then at the end you check and you haven’t checked. You don’t know that there is fremitus, and then you do your restoration and now you’re checking for fremitus and you feel, okay, there is fremitus here and you keep adjusting your restoration. And now your restorations out of contact. And then the contacts-

Getting thinner and thinner and thinner.

Yeah. And the contact’s still on the tooth and there’s still fremitus and you start adjusting the tooth. Now you’ve actually changed things because you don’t know what they were like before. Now you could end up removing more enamel.

You could end up essentially unnecessarily removing tooth structure or composite when you wouldn’t have needed to. Okay. So what was important to find out what the state is beforehand.

And also the problem with thinning the composite is even if you’re using a single shade, it becomes grayer becomes more translucent. It affects your aesthetics.

A hundred percent. A hundred percent. And if it’s there, it’s weaker. And the tooth, something else becomes a problem. First time they have their French baguette again, and then we’re going to check the bite marks with some articulating paper. So, I think both of us like to do it the same way, so I like to check the excursions first.

So, dry teeth, put the red paper in. Get the patient to close, get them to grind in all directions. Forward, left, right, you’re going to see some marks. And then I like to, once I’m done with the red paper, I get them to open and stay open. Put the blue paper in and just get them to tap, tap, tap. Just telling them to tap, tap, tap seems to work. That’s the one thing patients seem to get easily. Just tap, tap, tap on your back teeth. All right. And that will give you your results.

Now those new two occlusion, Mahmoud, why are you checking the excursions first and then checking the MIP? This is a basic tip, but I think for those who aren’t doing it already, they’d be like, oh, wow. It makes so much sense.

Yeah, I mean, because if you do your tap, tap first, then you’ve got your dot, and then you put the red paper and you get them to grind. They just smear the blue dot that you had everywhere, and it’s hard to tell where the actual dot is. So it’s easier to do the excursions first and then do the tap, tap, tap.


And then you need to document that. My preferred method, I think it’s yours as well, is just take an intraoral camera photo, right then it’s on the screen. I don’t have to worry about it. If you don’t have intraoral camera, you could either just try and remember it or you could sketch it out. Okay.

It’s really easy. Or you could describe it. You can write a note saying, protrusive contact on adjacent tooth. And really with the tap tap, you’re trying to see how far is the MIP contact going to be from my margin? Is it going to be on composite, is it going to be on tooth? And where is it relative to my margin? Because I want the MIP contact at least a millimeter away from my margin.

It’s such a huge tip there. I mean, if you guys, if anyone here is multitasking, you’re doing the gardening, you’re running and you just missed that tip.

Chopping onions.

You don’t want your dot, your chopping onions. Yeah. Yeah. The people who chop onions are good listeners usually. Okay. The Protruserati chop onions are the best. So the dot should be either on enamel. Or fully on composite, it should not be on the interface, which just makes sense, right? You don’t want to put all this force through your poor little interface.

Absolutely. And that’s why the reason you’re checking this before is cuz it might alter your prep design. So especially on Class III, for example, you might not bevel as far as the MIP contact, for example, if you know where it is, right? Because you don’t want that thin composite that’s sort of feathering down into nothing to be where all the occlusal contacts going to hit, because then that’s going to fracture, which means it’s going to stain and et cetera.

Okay? So we’ve documented our existing occlusion, so shim holds, fremitus, MIP contact your blue dot and excursions, your red lines, and you’ve documented-

That takes a minute. Like you said all these things and people thinking, whoa, you’re checking all this, you’re going crazy about the occlusion. But really all just it, it takes a minute, man.

It’s so quick. It’s only quick when this stuff is ready. So your nurse needs to know, have the shim stock ready.

Can you get the millers forceps out? Can you get the shim? So what’s the shim stock? It’s the silver one. Oh how do you open it? Get scissors.

Exactly. Exactly. But if it’s ready, it literally takes a minute. Okay, so once you’re done and you’ve documented that, now you’re going to go ahead and restore the tooth. Now, if you’re lucky enough that the Class IV that’s there is just failing aesthetically, you’re hopefully going to take our advice and maybe use a putty to conform. Okay? Just make your life easier.

If not, you’re going to use your digital matrix as they’re, say your thumb at the back and do whatever is you need to do. And then once you’re done, that’s when you’re going to check the occlusion, and now you can actually check it against the pre-op occlusion that you’ve documented. And for a Class IV, the way I like to think about occlusion, I think this is how we do it in OBAB, because occlusion could be very, like, it’s such a big topic.

Right. When people start getting confused, just break it down into five occlusal positions, and you can do this with any restoration anywhere in the mouth, and you’re going to think about five positions. Okay? Position number one is your centric relation. So if we go back a little bit, we did this in occlusion part two together, right? We talked about centric relation, but essentially-

And we talked about it in the last tooth in the arch syndrome episode.

Yes. Yep, yep. So lots of stuff to go back and listen to. If this quick description isn’t enough, but it’s essentially when the condyles are fully seated in the socket, in their snug position.

I think let’s skip over CR buddy cuz we can just talk about five hours for CR. So in this case we know that we’re conforming and therefore we know our joint position is, we can just ignore that cuz we’re just keeping everything the same.

Yeah, so MIP, so CR you don’t have to worry about it. Okay. Now MIP, what’s the secret with MIP, generally is forced distribution. You want as many teeth to contact evenly as much as possible. So your dot on your Class IV needs to not be high essentially. It shouldn’t be the only tooth that’s touching simple enough. Right? And ideally you want the tooth to contact where it used to before.

The other thing we already spoke about is the location relative to the margin, but also when we’re looking at the lower teeth. Even if there is space restoratively, but your MIP contact is against a really sharp bit on the lower tooth. This may be the time to smooth that lower tooth down and then ensure you still get MIP contact because you can build your composite as much as you want, right?

Because hopefully that’ll prevent that lower tooth from chipping later on. So again, just try and get broad areas of contact on as many teeth as possible. So that’s MIP. It’s very simple. Then you’ve got your pathways. Right. So pathways, basically just the path along the palatal. The lower incisors or lower teeth track, as the patient grinds forward, grinds sideways.

And the seeker here is, is we want to spread the load. So you want your contact to be on a broad area of contact. You don’t want a skinny line. I think you give the analogy of do you want to be stepped on by stiletto or by some flat shoes?


Yeah. So you want flat shoes. You want broad, and we give a lot of good vision.

Nice thick lines. Nice thick lines. Not these skinny chicken scratches.

Yeah. Because that’s spreading the load on that area. The other thing is, let’s say you’re doing an upper right central and when you check the occlusion beforehand, the upper left central had a line on it. What you want to make sure at the end is that line is still there because if the line on the tooth you haven’t restored isn’t there anymore, but there is a line on the tooth you have restored, it means you’ve put all that force in the protrusive guidance on your restoration. Yeah, it may be fine, but it might be too much.

Because if you’re relying on just looking with your eyes, without inking it up, then you’re missing that little detail that, hey, there was a line there before. Now there isn’t, and therefore my restoration or my tooth with the restoration is having too much of a line. You’re completely right.

Yeah. Okay. So broad lines, try and share the guidance if it was shared before. So that’s your pathways. Then edge to edge. An edge to edge really is where ceramic and composite restorations live or die. Because especially if you see someone with worn edges, and I mean, who doesn’t have some worn edges, to be honest with you, in this day and age, that’s where your restoration needs to have, again, broad areas of contact.

So if your composite edge isn’t at least a millimeter thick, how can you get a broad area of contact? You can’t, if your composite comes down to a knife edge, it’s going to be thin, it’s going to be a thin area of contact, and then it’s just easier to fracture it. So again, you need to build that into how you’re building a restoration.

So have at least a millimeter thickness all along the incisal edge. And then when you get the patient to go edge to edge, just check that you’ve got broad areas of contact that again, ideally are shared if possible. So in protrusive, if I’m restoring one central, ideally I want to see. When they’re edge to edge in protrusive, I’ve got contact on both centrals on broad flat areas of contact and it’s got to be smooth.

And that transition from the pathway as they make that palatal transition to the edges. There’s no jolt. It’s a nice smooth transition, which I know you talk about so much. But these checks, these five positions are checked pre-op and post-op.

Exactly. And then you’ve got a reference because either it stops you taking away too much or taking away too little because you have a reference. And the fifth position, again, we’re probably not going to go into too much detail here. It’s called crossover, but essentially it’s when they go onto edge to edge and then past edge to edge. And really the management of crossover is all about smooth transitions. We spend a lot of time on OBAB going over smooth transitions because smoothness really is probably the underrated hero of occlusion.

Cannot underestimate how important having to things smooth and not increasing resistance is to occlusion. And the last you’re going to check your envelope. Okay, so again, this is something we do not do. You’re, sorry, not last thing. You’re going to check your shim stock holds. Okay. So like you said earlier, if they had contact on this tooth in MIP before treatment, really, ideally they should have it again at the end. Why? Because if you don’t, that tooth could over erupt, could move, right? You’ve left it in a, maybe a slightly unstable position, so you want to replicate what the patient had before, and then you’ll check your envelope. So when they’re lying down, I’ll do my fremitus check. And I’ll compare it to what I had before. And then last thing, I’ll sit them up and I’ll do the fremitus check again.

Brilliant. Now because of the interest of time, I’m just going to say that was brilliant. I really enjoyed that chat. That was fantastic. And I think we’ve made it very tangible about occlusion on Class IV composite restorations, which again, no one talks about.

I’m just going to end by Mahmoud reading to everyone this awesome comment we had at the end of module one. So OBAB has five modules and this is just hilarious.

I know which one you’re going to read now.

Me and you are so scared that the first module would be the boring one, right? Because it’s quite lecture heavy where later we get cases and videos and that kind of stuff. So we were so scared about that. But then the feedback has blown us away from just module one. The boring one, right? So, Dr. Claire Laing thank you so much for your comment. It says, ‘excellent module guys. Thank you so much. I could literally kiss you both for clarifying between anterior and posterior guidance in a very clear way, especially, but I actually have a few takeaways from each section.

The models and diagrams used are also helpful. Also excited for module two, but very grateful. I can revisit module one whenever I want. Smiley face’. I mean, we’ve had so many great testimonials and reviews already. That’s my favorite.

Yeah. Yeah, definitely. That made me laugh. That’s brilliant. She’s clearly passionate about occlusion, eh?

Yes. This is our tribe. Yeah. This is our tribe. Yeah. Not because we are some sort of like tribal, like, crazy people about occlusion. We just want success. We just want restorative success. And part of that is occlusion. And like I said in the first module, we could have called Occlusion Basics and Beyond.

We could have called it the restorative course. We could have called it that because it’s, it’s, it’s one and the same. We spend too much time isolating the two, but they’re one and the same.

You know? No, I was just going to say, there’s nothing as practice building as when you get that patient that comes in and says, I’ve had this frustration done like six times in the past two years, every time I do it, it comes off within two months.

Can you help me? And then it’s usually an occlusal problem because most people just do not understand it. And then when you fix it and they come in, I usually make a bet with my patients. I’ll say, okay, how much do you want to bet I can make it last at least five years. I’m underestimating, just make I look good. And then when you do hit that mark, it’s just, it’s crazy. The patients think you’re a genius.

And you just have to make sure you educate them about the whole tooth to something else. If they play rugby, make sure they have their mouth guard. The whole cellar tape, the hair pin, the ice chewing, the chewing, what foods and how to consume certain foods.

When you have bonding, it’s, it’s about a puff aftercare of your bonding, right? It’s a piece of plastic glued the edge of a tooth ultimately, right? But, what you control and educate them on that, and then do all the things we said in this episode, which is to tooth to tooth, then really the only thing that can get the patient now is caries and stuff.

So hopefully, that part is under control as well. Mahmoud, thanks so much for giving up your time once again for the Protruserati. And you are always welcome guest, and I’m sure we’ll get you out soon. I think next episode we should talk about the whole thing about fremitus. Right. It’s such a fascinating topic, right?

Fremitus, the management. Is it okay to observe and watch fremitus? So if you guys want that, I’m not going to do it until we get enough comments on the video below that you want this, and then we’ll make it happen. If there’s no comments, then we won’t do it.

Fair enough.

Thanks, buddy.

All right, man.

Jaz’s Outro:
Well, there we have it, guys. Who knew that we could talk just 40 minutes and just scratch the surface of occlusion on a Class IV restoration. Hopefully there are lots of gems in there. Lots of peripheral things that you perhaps you may not have considered. And of course, if you knew everything they were talking about, it was hopefully good revision for you.

And after all, who doesn’t love learning about occlusion? If you want to do a deep dive, 30 plus hours into occlusion online, just like in this format, actually, individual videos, lessons that are five minutes long, 20 minutes long, a few odd half an hour lessons, and lots of clinical videos and case walkthroughs.

Then check out occlusion.online. It’s Occlusion Basics and Beyond online course with me and Mahmoud. If you are looking to take the next step in learning occlusion, that’s going to make your restorative dentistry predictable. If you’re not interested in learning more about occlusion or you are already enrolled on OBAB, then if you enjoy the podcast, don’t forget to give it a rating wherever you listen to it really helps me a lot.

But if you give the podcast a rating and leave a comment, If you can, thanks so much and we’ll join you in the next episode. And by the way, if you answer just a few questions, you can get a CPD or a CE certificate by being a Protrusive Premium member. You know the drill guys. Just answer those questions and you’ll get your CPD email to you.

Thank you again. I’ll catch you next time.

Hosted by
Jaz Gulati

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