Fremitus and Occlusal Overload – Dental Occlusion Geekiness – PDP160

Jaz’s Introduction:
Hello, Protruserati. I’m Jaz Gulati, and welcome back to another Protrusive Dental Podcast episode. If you’re new to the podcast, welcome. Thanks so much for joining us. And if you’re a veteran Protruserati, thanks for coming time and time again. We hope to make complex topics in dentistry tangible for you.

Protrusive Dental Pearl
Before we join the main interview with Dr. Mahmoud Ibrahim, I’m going to give you the Protrusive Dental Pearl, which I always do for every main PDP episode. Today’s Protrusive Pearl relates to cramp operations, and in particular, getting better impressions or scans. Look, once you’ve placed the retraction cord, and I know many people like to use things like Expasyl or Traxodent, which are like the pace systems.

I quite like using retraction chords and also in combination with PTFE tape, especially as I do lots of vertical preparations or VertiPreps. Now I have got lots of webinars planned in October. As part of the live series I’m doing for the Protruserati, the premium subscribers, it’s going to be VertiPrep for Plonkers.

So that’s coming soon. And one of the strategies I use to be able to scan subgingivally is once I’ve got my triple zero cord in place, I will put some PTFE tape over that. But sometimes what can happen is that the gingiva it sulks, right? It sulks on to the PTFE and sometimes even contacts the prep. So when I scan it because the tissues because the gums are touching the preparation it creates a nightmare scenario for my technician who wants that gingiva well out of the way So at that point the pearl the tip i’m giving you is if you’ve got a laser, fine. Great. Use a laser. If you’ve got any fancy burrs, use them.

But the cheapest thing you can buy is something called a Thermocut Bur. Now I’ve talked about this lots of times in a podcast before. It’s great for removing papillae, just removing soft tissue in general. But when you’ve got that sulking of the gingivae, and for those of you who are listening, follow along with me.

Those you’re watching, I’ll bring some visuals on the screen. Once the tissue sulk, you can just choose the correct size of Thermacut. And if you’re buying this for the first time, I’d buy the assorted set, things like a pack of six different sizes for different size for pillars and different needs, but I use a smaller one here and I just trough away the gingiva.

That little bit of sulking tissue and the patient’s usually already numb in this case and there’s hardly any bleeding when you do this and it’s just brilliant to get rid of that sulking tissue and now when you scan or you impress your technician will absolutely love you. So the tip here is to use a Thermocut bur, which will last forever, right?

They don’t have any diamond on them. They’re like a bold metal head. These are going to last forever. So definitely get a pack of these. And it’s wonderful for managing soft tissues in this way. So the next time you have some sulking tissues, pick up a thermocut burr and just get rid of it to allow yourself to get a better impression or a better scan. Let’s join Mahmoud now for the main interview and I’ll join you in the outro.

Main Episode:
Dr Mahmoud Ibrahim, welcome back yet again to the Protrusive Dental Podcast. How are you, my friend?

[Mahmoud]
I’m very good, Jaz. Thanks for having me again. I’m sure people are starting to get sick of listening to me talk now.

[Jaz]
Listen, this is what the people wanted, right? The Protruserati said explicitly on, in the comments on YouTube, they said, yes, we would like an episode on Fremitus. We kind of sort of teased them and said, if you want it, let us know. And they certainly responded in the comments. So here we are. It’s happening. We’re talking about Fremitus. It’s a weird thing.

It’s a weird thing. The term itself, Fremitus, Mahmoud, it’s a cool term. I like the word fremitus, right? And I actually didn’t know, being in dental school and stuff, and you read it in the textbooks and then you see it on your patients, and you don’t know what’s going on and we’ll elaborate on that today in terms of what actually is it and how do you manage it and how do you classify it? All those things. But actually, did you know Mahmoud that actually it’s a medical term?

[Mahmoud]
So I came across this, again, very recently just doing a little bit of bedtime reading and yeah, it’s like, chest fremitus, right?

[Jaz]
Yeah, so it’s like any body part, basically, you’re feeling some movement, basically, yeah, right, exactly. Vibrations, right? So it’s not a dental term at all.

[Mahmoud]
No, we feel everything.

[Jaz]
Which I thought was interesting. But, but Mahmoud, for those who, it’s the first ever episode of Protrusive they ever listened to, like random, tell us about yourself and how me and you are acquainted in this world of occlusion.

[Mahmoud]
Ah, okay. So yeah, I mean, Jaz and I, actually I stalked him for a while because he came up with Protrusive Dental Podcast and I thought he named the podcast after an occlusal term. This guy is cut from the same cloth as me. So, I stalked you for a while and we started talking occlusion and WhatsApp group developed the telegram, et cetera. And then about a year ago, we decided to create the occlusion course, OBAB, which took over our lives for a while and voila, we’re here.

[Jaz]
That’s right. And you are very much a wet finger dentist. The smiles that, you can just go on Mahmoud’s Instagram page and just see his beautiful dentistry. Like anything. Aesthetics, composite related, occlusion, restorative related. Mahmoud, you’re a guy, you’re very much a mentor figure on our telegram group. So, it’s great to see that. So for those who haven’t seen it, I’ll put it in the show notes. Do check out Mahmoud’s Instagram. It is just dental porn, right?

It is pure dental porn, mate. So let’s just not be around the bush. It is what it is. Right. So, it’s a great contribution for our Protruserati as well. And let’s take that further today, an episode on Fremitus. So what, we’d kind of defined fremitus in a way that we know it’s relevant in other medical fields and whatnot, but just in terms of dentistry, what is fremitus and how might it differ from mobility? Like, periodontal mobility? What’s the difference there?

[Mahmoud]
That’s actually the, probably the first thing that confused me when I first came across fremitus. I was like, why are we duplicating things? They are slightly different. So mobility is just essentially, and we normally test mobility using the two blunt ends of an instrument. So you’ve got your mirror and your probe, you flip them around and you use the blunt end one on each side of the tooth and you move it around and you see how much it moves.

[Jaz]
Why shouldn’t you use your fingers? Like, I mean, I’m guilty by the way, like I use the back of a mirror and a finger, whereas I know you should be using two hard instruments, right? Flat instruments. But I remember my perio tutor, Mrs. Zjilstra-Shaw, she taught me this. Do you remember the reason why we shouldn’t ideally be using our fingers to check mobility?

[Mahmoud]
Well, there’s too much squishiness in your finger, right?

[Jaz]
Yeah. It’s too much give, right? How can you check the movement of something with moving parts, right?

[Mahmoud]
Yeah, but no, I probably do the same again. I think what that probably does at worst is instead of you saying it’s a grade two mobile, you probably think it’s a grade one mobile. Maybe, but speaking of those gradings and stuff, do you know, it was like literally like 15 different classifications of mobility.

I honestly thought there was like two. Well, hopefully for the people watching, we’ll put up a, I’ll send you a list and it has the names, like two people will just get together every couple of years and come up with a new classification. They’re all almost the same, but just for reference, for example, so the one I use, I don’t know what I use.

I don’t know the name, but essentially grade zero or no mobility is whatever the normal physiologic mobility is, which in general is about 0.2 millimeters buccal lingually and 0.02 millimeters axially. So really that’s going to be almost imperceptible to you just using your naked eye. Grade 1, I like the one where it’s anything up to a millimeter of buccal lingual movement. And no axial movement.

Grade 2 is anything between 1 and 2 millimeters. Buccal lingual movement and there’s no axial movement. Grade 3 is anything over two millimeters buccal lingual or any movement axially whatsoever. Is that the one you use?

[Jaz]
That’s exactly the one I use but the interesting thing actually is, I remember being at dental school and checking mobility and presenting my indices to the perio tutor and what I found is that the things I was grading as Grade 2, was actually a Grade 1.

And so I was being too generous with my grading and really, especially on the loops, things look like they’re moving a lot, but patients and haven’t realized and whatnot, they realized very late on the mobility. Right? And I find that actually one millimeter, if you think about prepping a one-millimeter margin, you can see it quite clearly.

So, we kind of, the dental millimeters is elusive thing. So I think we’re too quick to give it a higher score. We’re actually Grade 1 mobility is actually a fair bit of mobility itself.

[Mahmoud]
It is, but you could also just be using a completely different classification to your period tutor under the same name, because it is really confusing. So, that’s mobility, right? So, the definition of fremitus is a vibration palpable on tooth-to-tooth contact. So why is that different?

You’re not using your mirror; you’re not using your fingers. You’re getting the patient to bring their teeth together either in sort of tap, tap, tap, MIP, maximum intercuspal position, or when they’re grinding, side to side, or forwards and backwards.

And essentially the difference is you’re then not just assessing whether, for example, this tooth has enough bone support, you’re assessing the effect of the occlusion on the tooth that has that level of bone support, if that makes sense. So, it could actually happen where a tooth has, say, Grade 1 mobility, right?

So, it does rock back and forth in its socket, one millimeter either way. But, if you put your finger on it, which we’ll explain exactly how we check for fremitus in a second, but, since you’re putting your finger on the upper tooth and you’re just asking the patient to tap, tap, tap, but you can’t feel any movement.

So you can’t feel any fremitus on that same tooth that has Grade 1 mobility. Why? It could be because that tooth is actually properly axially loaded. So the force is going up the long axis of the root and the patient has good distribution of contacts. So the force is distributed along amongst loads of teeth.

So that tooth isn’t actually being occlusively overloaded. So that gives you an indication that maybe the mobility is because of decreased bone support and it’s got nothing to do with the occlusion.

[Jaz]
Yeah. I mean, it’s all related between their periodontium and whether it’s reduced or not, or if it’s like, they’ve got loads of bone, there’s bone builders and there’s bone destroyers.

So if they’ve got plenty of bone, they’ve got like lingual tori coming out of everywhere. So, those people are like bone builders, and they very rarely have mobility. Whereas when you got like true periodontal disease and destruction, and you get a reduced periodontium, you’re going to have mobility, but it doesn’t always guarantee that you’re going to have fremitus.

But you’re more likely to see fremitus in someone who’s got mobility anyway. But then you could have the scenario where we see quite often where you have a tooth that displays fremitus, i.e. the patient bites together and you see this movement of the tooth. It’s like a piano key movement of a tooth.But when you take a radiograph, you see all this bone and you think, what’s going on there? So just break down what’s happening there.

[Mahmoud]
It could be that actually, it’s just the periodontal ligament space is slightly wider in that patient than it is in someone else. So that tooth has a little bit more give and that could have been just an adaptive response.

So essentially the body’s decided, okay, this tooth is taking a little bit more load. So I’m just going to widen that ligament a little bit, give it a little bit more give. Just makes it less likely that the tooth is going to wear or fracture or become sensitive.

[Jaz]
It’s like a shock absorber, which is what the PDL is. The PDL is a shock absorber. And then when you have a thicker amount of PDL, if you like, then you get this more give, which is actually not a bad thing. It’s like a cushion. We were talking earlier, we hit record button. Tell us about how it can work as a cushion.

[Mahmoud]
Well, again, a very well-known dentist, I’m trying to remember the name, but very, very talented restorative dentist. A bit of mobility can be a gift to the restorative dentist because that tooth already can dissipate some of that force by just moving out of the way a little bit. Obviously, you don’t want to treat teeth that have excessive mobility, and you want to be assessing the periodontal health of the patient, etc.

But because it just moves out of the way, if you imagine that tooth just naturally is going to hit first as the patient closes. Just a teeny, teeny, teeny bit before everything else. But as the rest of the teeth come together, that tooth just moves out of the way, the rest of the teeth come together and dissipate that load.

So essentially that tooth has just developed this sort of protective mechanism, just moves out of the way a little bit. So that it waits for all the other teeth to come and help it along and take that load. So that’s how it can be sort of a protective mechanism or an adaptive mechanism.

[Jaz]
Well, the other thing that can happen in that scenario is if that tooth keeps hitting first and it’s not moving out of the way quickly enough or is being stubborn, then the only other sequela is that tooth is either going to wear away, which is a slower thing, or break or crack away, right?

So this is all a sign of some sort of timing of the teeth coming together or occlusal overload. So the tooth is overloaded before everything comes together. And there’s only so many different ways overload is manifested on the teeth. And this could be the whole thing about occlusal disease, right? Wear, mobility, migration, as in teeth drifting, cracks, that kind of stuff. When you break it down like that, have you come across, are you familiar with the weakest link theory?

[Mahmoud]
Yes, I am.

[Jaz]
So for those who don’t know, the weakest link theory is, it’s just a theory, but I like how it explains what we see our observations. And there was this like one study where they observed like 15 people. And if you look at our own patients, look at your own population of patients, right?

Patients who tend to have periodontal disease and general mobility all around. Do they have significant wear, or do they tend to have like virgin enamel? A lot of these patients will have virgin enamel, right? So, bear that in mind. And then sometimes these patients who are like these severe bruxist and they’ve got like horizontal flat wear all across, but these guys have got like tori and there’s no mobility and almost like they don’t have a PDL, right?

They’re like their teeth are set in marble, right? So, the weakest link theory suggests that actually, I guess one way to summarize it would be that if someone has got this give this cushioning that maybe they’re more likely to get more mobility and periodontal destruction as their way of absorbing the load.

Not that we’re saying that occlusion or occluding or power function causes perio. We know that that’s bacteria. Let’s get that straight. But someone whose weakest link is not the PDL. It might be the teeth, but their teeth might be the weakest link in the chain. And for someone else, it might be the muscles.

So actually, all that parafunction, all the occlusal overload, the teeth are maybe damaged a little bit. The PDL absorbs a little bit, but most of it is being absorbed by the muscles. And that’s why they’re getting headaches and muscular origin of TMD. Is that something that you’ve observed in your own patients, Mahmoud?

[Mahmoud]
100%. I mean, you see a lot actually where you do observe, especially, you see the perio patients and they almost never have any wear, and they can’t break a tooth by sort of clenching on it because it just moves out of the way. Whereas the opposite is true. You see these patients with severe wear, you almost never have to treat gum disease before you can then go ahead on and do the restorative.

Sometimes you have to teach them how to brush their teeth because they don’t do it. But they’re just not prone to perio disease. But yeah, you almost never see both parts of the articulatory system. Both the periodontium and the teeth failing in the same patient, it could be perio and caries, but you very rarely see perio and wear to the same sort of extent.

[Jaz]
I’m going to put the paper, the weakest link paper, they’re very small paper, small sample with just philosophies and observations, which I think are nice. I’ll put that in the show notes for those who want to geek out to read. I think it’s a cool thing to read. So we covered-

[Mahmoud]
It makes sense, doesn’t it? When you think about it.

[Jaz]
Yeah, when you say that the teeth move out of the way and that’s why the enamel itself is spared, it just makes so much sense, right? It’s like an observational thing that we make in our patients. The other thing that actually reminds me is that Pasquale Venuti shared this with me once. He says, people are either ‘wearer away-ers’, or he didn’t say it like this, but people are either ‘wearer away-ers’ or ‘cracker away-ers’, right?

People either just show you lo loads of wear or they show you loads of cracks. And it’s just how the mechanics come into play, how the tooth absorbs that stress. What are the sort of angles of the articulate eminence and all these amazing physics that come together in your own, the biophysics that comes together.

So it’s amazing how yes, of sometimes you get wear and cracks and whatnot, but it’s either a ‘wearer away-er’ or a ‘cracker away-er’. So I love these kind of observations in our patients. We’ve covered a fremitus, what is it in terms of how we actually see this in our patients. But how do you actually, have you covered yet how we check for it?

[Mahmoud]
No, I said we would.

[Jaz]
Let’s do it.

[Mahmoud]
So essentially, because it’s a movement that is palpable, okay, so we’re going to put our finger, gloved finger, on the upper tooth usually, because obviously it’s the lower tooth is going to be hitting the back of the upper tooth, right? So if the upper tooth is going to move out of the way, you’re going to feel it on the upper tooth.

So you put the pad of your finger on the upper tooth that you’re checking, and you should get the patient to tap, tap, tap, and you will feel the tooth either vibrate and push your finger out, or you won’t.

[Jaz]
And of course by tap, tap, tap, like we mean their maximum intercuspal position, right? Their bite, the best fit. Whereas you don’t get your patient to bite edge to edge. Obviously, you get them to bite into MIP, despite your patient, what they want to do is bite edge to edge when you want them to bite MIP, but yeah, get them to bite, functional. Okay. Get the teeth together and then you observe and then you feel with your finger.

Just like you said, there’s actually a fremitus grading, right? Which we observe and we know exists whatnot, and you can go into detail. You check the mobility grade for everything. Then you check the pharmacist grade for everything. But I think that’s overkill, but it’s good to know. It’s interesting to know. Can you give us some details about the fremitus grading?

[Mahmoud]
Yeah. So essentially grade zero is no perceptible fremitus you can’t feel anything. Essentially it comes in three classes. So class one fremitus is no, so it’s a very mild vibration. So something within the physiologic limits of movement.

So like we said earlier in the episode, a tooth has a normal physiologic mobility, bucco-lingually lever about 0.2 millimeters. So it’s very, very, very small. So you might not feel anything on your finger. A good way to sort of calibrate yourself for this, because it’s the first time you put your finger on a tooth, you probably don’t really know what it’s supposed to feel like. If you get a patient who clearly has no wear, no perio disease, generally very healthy dentition, put your finger on, say, a molar tooth or an upper molar.

[Jaz]
Yeah, it’s very much the tip of the finger, like, sunk in. If there was, no one’s ever done this before.

[Mahmoud]
Yeah, and then just get them to tap, tap, tap into their MIP. Chances are they won’t have very much fremitus on that tooth, and at least that will give you an idea of what a lack of fremitus or class 1 fremitus would feel like. Now, a class-

[Jaz]
This is very much normal. We use this day to day, don’t we, Mahmoud? When we’re restoring, let’s talk about each class and this is actually really valuable information in the sense that if I’m restoring, let’s say an upper right lateral incisor, I’m doing a class 3 restoration.

I hate doing class 3s, right? But let’s say I’m doing a class 3 restoration. As part of my occlusal checks. Yes, I’m going to check the shim hold of the tooth in front and tooth behind. I’m going to check the dots and lines. And if I’m conforming, I want to copy those features. But then if I’m checking, which I would do pre op is fremitus of that tooth.

So the patient bites together. Obviously, if they’ve got a incomplete overbite there, there’s going to be no contact and there’s not going to be any fremitus at all. But if they’ve got contact with the opposing tooth, then you can check. Okay. When they bite together, oh, there’s no vibration, a very minimal vibration. So if you finish your restoration at the end, and as part of your checks, you feel a heavy vibration, that you need to continue adjusting that restoration. The bite’s not quite there yet. You also do the fremitus and excursions check as well to make sure you haven’t placed too much excursive load on that tooth, right?

[Mahmoud]
Yeah, I love doing that because the other thing is imagine this tooth also has a degree of mobility, right? Now, when you’re checking your excursion on this tooth, if you’ve got your finger on it.

All right, and you can feel the vibration. Yeah, you know that maybe the contact on it is too high but also what you’re doing is you’re making sure it’s not moving out of the way and then you’re picking up other contacts. Does that make sense? So I like to when I check my say we’ve done that lateral incisor restoration and I’m checking Protrusive and they happen to have a contact on this tooth in protrusive. If you’re putting your finger on that tooth while the patient is grinding forward you’re making sure that tooth isn’t just being pushed out of the way and then you’re picking up marks on other teeth at the same time, which is maybe giving you a false sense of security that, my protrusive contact’s still on the centrals.

Actually, what’s happening is the lateral’s slightly moving out of the way. If you keep your finger on it, right, you’re going to feel that vibration. You’re going to know that it’s actually being hit first, but it’s moving out of the way, and then you’re picking up the others.

[Jaz]
Yeah, so the occlusal overload is being absorbed by the tooth, and if you didn’t check with your finger, you wouldn’t have felt it.

[Mahmoud]
No, and the lines that you saw on the centrals would have made you think, okay, actually, the lines are still there, whereas this tooth is actually being pushed out of the way. So, example, this may be a post ortho case, right, and you’re doing this, you’re edge bonding or whatever, and there’s still a little bit of mobility, right, you’ve just finished aligner treatment.

And now when you’re doing your protrusive check, you think, okay, I’ve got lines on my centrals. So my lateral isn’t being overloaded. But if you hadn’t done this check, you wouldn’t know that it’s actually being pushed out of the way. And then when your fixed retainer fractures or the tooth relapses, moves a little bit more buccally, then you’re left wondering, why did that happen? I thought I had my protrusive guidance on my centrals.

[Jaz]
Very true. Yeah. Post ortho is a great example when there’s some increased physiological mobility, which is a temporary. So I think as part of your protocols, if you’re not already checking fremitus. It’s a really good thing to check for your restorations.

And if there is a degree of fremitus, then really, we want to maintain that same degree of fremitus if we are conforming. If we’re trying to keep everything the same, then that’s that. Let’s just wrap up with class 2 and class 3 fremitus just for… But just to be academic.

[Mahmoud]
Okay, so class two is when the vibration is easily palpable. So you can feel it with your finger, but you can’t see it with the naked eye. So if you didn’t have your finger on the tooth, and you just asked the patient to tap, tap, tap into MIP, you wouldn’t actually see the tooth move. Class three is when the movement is actually just visible to the naked eye. So I see this sometimes on premolars.

[Jaz]
That’s quite severe.

[Mahmoud]
Yeah, so you see this sometimes on premolars, probably easy to see because you’re looking straight ahead. And you can get the patient to just grind left and right a little bit and sometimes you can see the premolar just move out sideways because there’s an incline contact on it.

[Jaz]
And so all of this, if we think of it as a sign of occlusal overload, and one thing I did mention earlier actually is that that patient who you take a radiograph and you see all this bone.

And actually, you mentioned that this could be an adapted tooth, the PDL could be thicker. But sometimes if you see the funneling type of bone loss, that is quite a pathognomonic of occlusal overload and then occlusal trauma. We can now introduce the term. This is a type of occlusal trauma. If you get loads of bone, but you’ve got significant fremitus and then it’s got plenty of bone there, but then it’s got this funneling type bone loss, then that is occlusal overload.

So then the next question is, should we be treating it? Should we always be treating it? This is a tough one. So if we take a bit tooth by tooth, if it’s just one tooth affected. Where do you draw the line? Okay, let’s treat the entire dentition to help this one tooth versus a few teeth have it, and then, and you got cracks, and you got some potential wear in a different patient, and there’s a real need to carry out restorative dentistry. That’s a different kind of patient. So it really has to be a case by case thing. But how do we even begin to dissect? How do you begin to treat these cases?

[Mahmoud]
So, I mean, I don’t think I’ve ever sort of set out necessarily to treat fremitus as such. I would say the way I use fremitus, all right, let’s take simple examples first.

You’re conforming to the existing inclusion, okay? You’re not going to change the patient’s bite. You’re going to do your pre op check. You’ve checked this tooth and it has no fremitus on it. That’s the easy one because I know once I’ve done the restoration, I want to have no fremitus on this tooth.

Now, if I check the tooth and it does have fremitus on it, you’ve now got the option of either getting rid of it or maintaining it. Now, in most cases, I would say, if I see that the patient has an otherwise relatively intact dentition, they’ve got sufficient contacts around the arch. The tooth isn’t the main guiding tooth in that movement.

Then I will probably get rid of the fremitus by lightening the contact on that tooth. If on the other hand I see that there is a ton of wear everywhere or lots of cracking or the patient doesn’t have that many pairs of teeth that can take the load, then it might be time to just have a discussion with the patient about the more extensive problems they have.

So I’m not going to necessarily willy nilly just go ahead and get rid of it but I would say to them, look, there are other issues here. Okay, we’re going to stabilize this caries or whatever. We’ll just let them know that they may have occlusal disease. And it’s something that we need to look at. Now, the other time I use fremitus a lot is when I’m doing, for example, DAHL. So when I’m doing a DAHL case, essentially building up the upper three to three and I’m opening the vertical dimension.

[Jaz]
So it’s for those of our folk in America, three, three, we actually mean canines, canine, three, three, three, three. And in U. S. land means first molar. Well, actually no, it doesn’t mean three to 19 or something. I don’t know, man. I don’t know how they do it.

[Mahmoud]
Yeah. Something like that. So upper canine to canine, for example, I absolutely do not want any fremitus on those restorations, because I’m already, I’ve already got fewer teeth contacting, right? So I want to make sure that load is going up the long axis of the tooth as much as possible, and any guidance is shallow enough not to induce fremitus. Because that makes me feel, at least, that I haven’t put too much load on these teeth that I’ve just restored.

[Jaz]
Mahmoud, before we move on actually, it just reminds me of a Protruserati who reached out to me saying that she’s done a resin bonded bridge as the DAHL. So basically, all the load is on the wing and then nothing around the arch is in contact.

And so she messaged me and she says, look, I’m a little bit concerned because this abutment tooth whereby the wing is bonded to is displaying lots of mobility. Now I’m thinking, well, what do you expect right now? I think she was expecting just pure intrusion and everything else just comes into play.

But it just doesn’t work like that, right. To get those perfect axial loading. It doesn’t always work like that. And I think unless you purposely plan it in a clever wing design and maybe adjusting the opposing tooth in a certain way to actually give you the contact you just desire. What can happen if you’re DAHLing from just one tooth is very much expected.

You get some physiological movement and then it moves out of the way to allow all the other teeth to get in touch. And then it’s only going to get better if it now stays in that new position, right? It’s like instant orthodontics, if you imagine. But if it keeps wanting to come back to the original position, then that tooth will forever be mobile.

[Mahmoud]
And it can develop sensitivity, which I believe I think happened in that case. Cause I think we were talking about it. So, that can also lead to sensitivity, it could lead to wear, it could even possibly, I guess, debond the bridge. So, I’m not a big fan of doing DAHL on a resin bonded bridge on one tooth. Purely because of the occlusal overload.

[Jaz]
Yeah. And so that is an example of a very pure example of occlusal overload, which the patient hopefully adapts to, but sometimes things don’t go as planned. They need to decide, okay, what length of time would you monitor things? And sometimes that tooth will remain just a little bit mobile for many, many years without any negative consequences thereafter.

And it’s just the way that the patient adapts. Now there’s one more thing you were going to say. Actually, before I interrupted you with that example.

[Mahmoud]
No, I was going to say, so envelope of function. So big, big use for me from it’s checking, it’s probably my favorite way of checking the envelope function.

So for anyone who hasn’t listened to us talk about envelope of function before, essentially your mandible has a trajectory of movement that it likes to do. So if you imagine the way you write with a pen. Every time you write the letter A, your wrist is making a particular movement.

It’s just how you’ve trained yourself to do it. And same thing with the mandible. It just has a natural swing. If you put something in the way of the path that the mandible wants to take, you could encroach on the mandible’s envelope of function.

[Jaz]
Which, by the way, I like to call the chewing space.

[Mahmoud]
Possible consequence of encroaching on an envelope of function is you could develop in that tooth that is in the way. So again, if you imagine your post ortho cases, you’ve retracted your upper incisors, you’ve unfurled all the crowding on the lower incisors and you’ve tipped them forward slightly.

And now, as that patient’s mandible wants to move, those upper incisors are in the way and you keep getting, and the lower incisors are bumping into them, so you’re developing this sort of fremitus. It’s something I always check for on finishing my sort of orthodontic cases, especially if I’m putting in a fixed retainer.

You want to try and pre plan space for your fixed retainer so you don’t have fremitus on those teeth afterwards because of risk of the retainer fracturing or you can either, you can even get relapse, the upper incisors could want to drift forward, move out of the way.

So for envelope function testing, it is key that you do this with the patient sitting up. So, do most of your checks with the patient lying down because obviously you don’t want to destroy your neck. But always sit the patient up, fingers on the front of the incisors, and then just get them to a tap, tap, tap in their MIP. And also I get them to grind forwards, grind left, grind right. And I want to see if I can feel those teeth being pushed or feel the vibration on them. That’s probably my favorite way of doing it.

[Jaz]
Well, you’ve just described a scenario whereby if you finished your orthodontics, let’s say you do a clear aligner case, and you finish with a complete overbite, and now you haven’t really got space for a fixed retainer, but you promised your patient a fixed retainer, so you’re going to damn well deliver your patient that fixed retainer, right?

So now you essentially have a occlusal overload on the anterior teeth. And then either the fixed retainer is going to break or you’re going to get some like an on-block mobility and fremitus of the, maybe the lower incisors and the upper incisors.

And essentially you have encroached the on-envelope function. And when the chewing, there’s no chewing space and things are rubbing, and things are wearing. So it’s not ideal. So we’ve induced that in that case. And that’s not good. The patient may complain that it’s hitting together. The teeth may just move out of the way.

Fremitus or you get accelerated wear and fracture. So all those things that we discussed about before, but let me tell you a scenario where I had a patient who displayed fremitus. So every time she was biting together, she had clear fremitus on her anterior teeth. Okay. Mostly on the upper incisors, a little bit on the lower incisors.

And so her main issue that I treated her was for her headaches, her TMD headaches and muscular pain and just protecting her teeth from this very significant power function, large masseters. And so I made her a nighttime appliance and she had a severe awake bruxism habit. So temporarily, as I was trying to make her aware of this habit, I made her awake bruxism appliance, which if you want to read about more, I’ll put something in the show notes about the kind of appliance I use for that.

And so essentially, she came back. And her fremitus was significantly reduced. Like it went from, on some teeth, it went from like a class three to a class two and other teeth went from a class two to a class one. Like it went, dropped the whole class. I’ve never yet found someone going completely from class two to a zero kind of thing is, or that kind of stuff.

So it’s significantly improved. And the patient even noticed the, yeah, they’re feeling like they’re less mobile, which is great. Now, fast forward three months, she came in and she had fractured her upper lateral incisors. She came in saying, this tooth hurts, something weird about it.

And under magnification, I can see a horizontal crack at the CEJ. And I just checked that actually it was a cervical third root fracture, essentially on this tooth. And you think, and it made me think, okay, what’s actually happening here. And it is exactly all the things we’ve been talking about, Mahmood.

It is occlusal overload. And when you remove the weakest link, when you strengthen the weakest link, which was her periodontium, right? When I actually removed the forces and I made the teeth firmer, it was the tooth that became the weakest link. Now, this is extremely rare scenario, and she probably already had a history of trauma from that tooth or something.

It was a virgin tooth, by the way, which is scary, right? And now she’s gone to have an implant and stuff. And we worked really hard to make sure that we know there’s no envelope function issues, and everything’s well protected as well. And also there’s these occlusal adjustments to make sure that there’s no such thing as occlusal overload in her mouth.

So we’ve worked really hard to do that. But it’s still an interesting anecdote that maybe all fremitus doesn’t need treating after all. That wasn’t my aim. My aim was actually to help her muscular pain and headaches, which we managed to do, but what an amazing finding, unfortunate for the patient, but interesting change in how the body adapted.

[Mahmoud]
Yeah. That’s the thing, right? So every action has an equal and opposite reaction in a way. So you took the load off of the periodontal. We have to go somewhere, but I think it’s also important to note that most things are going to be very important in certain patients. Okay, there’s going to be a lot of patients out there where a lot of this probably doesn’t matter to a huge degree because they don’t parafunction, they don’t clench, they don’t grind, they don’t put that much force through the system, but there’s going to be a few, and it’s usually the ones that already display fremitus because that is telling you that there is a bit too much force going somewhere, or the ones that display wear, display mobility, drifting, sensitivity, cracks, it’s those patients that you know are just putting too much force through the system and the weakest link, could be the teeth, could be the periodontium, and something’s going to give, so you’re then, your responsibility then is to make sure you’re trying your best to redirect those forces towards the systems that are best able to handle them.

That could be as simple as just spread that load, right, so instead of it going on one tooth, maybe go on two, or on three, or whatever it may be, and that may be enough. It may be splint therapy, it may be ortho, move the teeth out of the way that mandible wants to move in a particular way and the teeth just happen to be in the way because they’re crowded.

So, it’s not that you have to be super diligent with this with every single patient, but certain patients this would make a big difference to your treatment plan.

[Jaz]
I had another patient who had a class 2 fremitus, maybe even borderline class 3, and it was yeah, I’d say it’s class 2, I can see it in my eyes, right?

And then I treated her with orthodontics because she has some like spacing on her front teeth. So we literally retracted a lot of stuff trying to make sure we didn’t encroach on the airway. It wasn’t like significant major kind of stuff, but we got rid of the diastemas. We did a bit of composite bonding, and I made sure that I finished with enough overjet, like way more than what she had before.

And I use my T scan and I use my fremitus test and everything. And I finished at the end with a bite. I was happy with, with no signs of occlusal overload and her fremitus was like way better, whole class better once again. And that stayed better. We had enough space for a fixed retainer as well, because we planned that from the start.

And so initial situation was that the front teeth would get overloaded. They would move out of the way. And then the back teeth would come together. And then by creating a scenario where the back teeth and the front teeth kind of hit at more of a similar time. And there was enough overjet. That’s how we managed her.

Although the fremitus improvement was like a secondary driver. The first primary driver was cosmetics, right? She didn’t like her spacing. She didn’t like the fact that relapse had happened from a previous ortho so just another anecdote that I’m not going around breaking my patient’s teeth or anything. And I do get success for treating fremitus in the real world as well.

[Mahmoud]
I mean, I think what we were trying to get at is that. Fremitus on its own is not a disease. If you think about it this way, if you’re driving in a car and it has no suspension, if you want to feel no vibration when you’re sitting in that car, that road better be absolutely marble smooth.

And that would be the equivalent of you needing to get all the teeth to touch at exactly the same millisecond. I mean, T scan or not, I don’t think you could do that. So we’ve got this built in suspension system, right? Each tooth is suspended in its own little socket. So that gives you a little bit of leeway where it’s like, okay, if this one hits, two tenths of a second before this one.

With a little bit more force, it doesn’t matter, right? It can, it’ll absorb a little bit, this one will intrude a tiny little bit before this one hits, and then everything will sort of balance out. So you just got to get it close enough. The only other thing I want to say is always check a few other teeth as well.

Like if you’re just looking at that one tooth, you’re getting tunnel vision. It’s hard to know what’s normal for this patient. So if I’m doing some composable, I’ll check all the anterior teeth, right? Because if this patient has class one fremitus on all of their teeth, like all their anterior teeth, everything’s sort of just moving out of the way a little bit as they bite.

Like I think, okay, I’m still getting equal loading, right? It’s just, everything’s just hitting a little bit early. Maybe what I need to do is just keep it even. Don’t then have it where it’s just one tooth that’s hitting early. Because at the moment everything’s stable, everything’s hitting together. If maybe just moving outta the way a little bit. So again, that’s the gift to the restorative dentist.

[Jaz]
Well said. And I love the car suspension analogy. That’s brilliant. And I think the ending message I guess, of this podcast is, so sometimes fremitus, well it is adaptation, right? It is a type of adaptation. It’s an adaptation to occlusal overload, but then the adaptation happens to then make the consequences of that occlusal overload less severe over time, because a little bit of give in the system, a little bit of fremitus to spare you from the fracture, the wear, the cracking, just like you said, it’s like a cushion.

It’s a gift to the restorative dentist. And so what we shouldn’t be doing is going around treating everyone’s fremitus, unless there’s another few other reasons to treat as well. And then when there are enough reasons to perhaps do comprehensive dentistry here, then part of your goal should be to have no occlusal overload, which itself would help greatly with the fremitus anyway.

That’s one of the things that we do. We don’t go out to treat fremitus. We go out to manage to make sure we get equal as possible occlusal loading and that itself would help.

[Mahmoud]
Yeah, I think if I was to summarize this in like literally just a few sentences and if you didn’t want to take away all of that and just take on one thing, do the fremitus check before you’re putting your restoration in.

So check it before and the way we do that is you put your finger on the facial of the upper tooth like that and just in MIP, just get the patient to tap, tap, tap. Tell your nurse, yeah. I can, if it’s positive, if it’s negative, you don’t have to classify it. Is it there, or is it not there? And then check it at the end, when you’re done.

And the key is, if it wasn’t there before, make sure there isn’t any at the end. That’s probably the most important thing, because that’s the only time you’re going to, you’ve just introduced excessive force to, if there was no fremitus at the beginning, and then there is once you put your restoration in, you’ve just added more force than there was before. That’s probably the most important thing if you want to keep it really simple.

[Jaz]
And definitely, you mentioned it earlier as well, but there’s premolars, like sometimes in a patient with these large masseters and maybe missing a molar or a couple of molars, and then you check their tap, tap, tap, everything feels fine.

But as soon as they go into excursion, because of the steep angles of those premolars. It’s not that they’re discluding into, or it’s not that they’re going into beautiful group function that might be happening, but it’s taken the whole premolar is actually moving along with the mandible. And that is a degree of fremitus in excursion, which you’ve got to watch out for and document and then think, okay, am I going to accept this and monitor over time or is, are there enough reasons to treat this case?

But then that really has to be a case-by-case thing. So Mahmoud, I think you’ve summarized everything beautifully yourself, my friend. Thanks so much for giving time to talk about fremitus. And if you guys want to learn more from me and Mahmoud, check out Occlusion Basics and Beyond. It’s our flagship online occlusion course, and we worked really hard on it.

And it’s been just amazing. The feedback that we received, the testimonials we’ve been getting already. And it’s only been like, gosh, three, four months since we, yeah, four months since we launched. Got a community of dentists commenting daily. Like me and Mahmoud are daily replying on the comments and the lessons. And it’s just been amazing to read the comments.

[Mahmoud]
Yeah, yeah. It’s been really, really gratifying, hasn’t it? And yeah, I mean, I love getting the notifications and reading the questions and the comments have been absolutely amazing.

[Jaz]
Amazing, Mahmoud. Thanks so much, my friend, and I’ll catch you next time.

[Mahmoud]
Thanks for having me, guys.

Jaz’s Outro:
Well, there we have it, guys. Thank you so much for listening all the way to the end. If you like the kind of things we talked about, then check out our upcoming live webinar. It’s called Unchippable. What are all the strategies that me and Mahmoud use to make sure that we don’t get any chipping of our anterior restorations?

Now, Mahmoud does lots of composite bonding. I do a fair amount myself. And I’m confident that when I’m doing my bonding, that nothing’s going to chip, right? I’m actually, bold enough to say that I’m confident the way I manage my occlusion. And so I’m going to share all that with you. And so is Mahmoud.

So if you’re enjoying our webinar entitled, Unchippable. All you have to do is go to protrusive.co.uk/unchippable, and that will take you to the registration page. And in case you’re very early and we haven’t quite launched our webinar yet, then you’ll be added to the waiting list. So as soon as the webinars launch, you can join it.

If you’d like to claim CPD for this, just answer a few questions and get your certificate. This will of course be on the premium app. So for those of you who subscribe on www.protrusive.app, or you’ve got the Android or iOS app, use your login and get CPD for all the protrusive episodes. And premium clinical videos, which are exclusively just for the app.

Like last month we put the webinar recording for quick and slick rubber dam. So that was like a recording that we uploaded. And we also added a video version of an occlusal exam. So picture and picture occlusal exam, which was also eligible for CPD. So check out protrusive.app if you’d like to see that. Or just answer a few questions for this episode.

Lastly, of course, if you really want to go the whole hog and learn from me and Mahmoud, then check out Occlusion Basics and Beyond. It’s our online occlusion course, and it’s just amazing. We’ve been blown away by your feedback. And since we launched in April, we actually added four more hours of content and we just love reading everyone’s requests and trying to add as much value as possible to make this the greatest occlusion course on the planet, but also just generally make occlusion tangible, this big, confusing topic, make it tangible with. cases and step by step protocols.

So if you want to check that out, head to occlusion.online. Thanks again for listening all the way to the end and I catch you same time, same place next week.