Interproximal reduction (IPR) is a useful way to create space in Orthodontics, but it has to be performed carefully to make sure it looks good and is effective.
If you are new to Orthodontics or have never performed IPR before – this episode is for you.
I am joined by Dr Devaki Patel, specialist Orthodontist, to discuss IPR techniques and the nitty-gritty details and answer the questions you always wanted to ask about IPR…but never did!
GDP Orthodontics has boomed in the last 10 years. More and more of us are treating orthodontic cases and often this may be referred to as Short Term Orthodontics (STO), or Anterior Alignment Orthodontics (AAO).
Protrusive Dental Pearl: If you view a ClinCheck or a similar 3D simulation, make sure that the initial bite/occlusion is set yup correctly. You will be surprised in how many cases this may be wrong and it has not been picked up!
If you are starting out with Ortho cases, IPR may be something that worries you. You may have questions like:
- Which are the best strips?
- Are strips better than a bur?
- How should you hold/orientate your bur?
- How do you perform IPR when there is crowding?
- What are the secondary benefits of IPR?
- Should you place fluoride after, or is that overkill?
A really great and helpful guide to IPR
If you enjoyed this orthodontic episode, you may also enjoy my episode with Dr Almuzian on whether Class I molars are really that important?
I appreciate you all listening – do subscribe on your preferred podcast platform so that you do not miss the latest episodes.
Click below for full episode transcript:Opening Snippet: You know, 9 out of 10 patients, they'll come in saying, I don't like this. And like you said, as the teeth straightening, they spend so long looking at their teeth, they'll find other things that are like. So it's just always worth gathering this information at the beginning, you know, as much as you can. And so you can exceed the expectations rather than under deliver...
Jaz’s Introduction: Do you remember when you had to learn a new skill? Maybe in dentistry, you are learning a new technique, a new procedure? Maybe you were learning orthodontics? What were the things that you’re most worried about back when you were starting out? Or maybe you’re thinking about going into orthodontics? What is it that worries you? You know, for me at the beginning, I have to say IPR was a tricky subject, because it’s not really the theory, because the theory makes sense. You know, you create some space, you move some teeth, the theories are fine. And we know evidence base suggests is pretty safe, if done well. And we’ll talk about that in this episode. But it’s more about the How to and How not to do it wrong. Because once you’ve seen the photos of when it has been done badly, then that’s all haunts you. So when you’re there doing your IPR, you’re under doing it at the beginning, you’re not doing, you’re not creating enough space, and therefore you’re not meeting your treatment objectives as fast enough. Or if your God forbid, removing it overzealously or your technique is such that it’s leaving your teeth in a slightly suboptimal morphology. So these are all the considerations I was having when I was starting out IPR. So then I consulted some mentors and a principal who was very helpful in helping me to do the right techniques using the Bur. My principle taught me how to use it. And I’m very thankful for that. It can be a topic that can be of concern to some people, because we all want to do a fantastic job for our patients. And we all want to do it safely and effectively. So this episode will hopefully cover a lot of the nuances of interproximal reduction for orthodontics. And I hope it helps, I’m joined by Dr Devaki Patel, who is a specialist orthodontist. And she’s gonna be showing us a few diagrams, a few of the strips that she uses, and how to use all these sorts of tools, when to use them, when not to use them. Because you know, it’s very much case dependent. Every case will come at you with this unique challenges. And therefore you have to adapt your techniques to be specific to that patient you’re treating. The Protrusive Dental Pearl I have for you is an orthodontic one, because chances are if you’re watching or listening to this, then maybe you’ve already started dabbled in orthodontics, maybe you do a fair bit of orthodontics already. So it’s only right that I make the pearl an orthodontic one. And chances are but nowadays, you may be using a clear aligner system of some description. Now, some of these clear aligner systems have got their softwares which they can emulate a virtual teeth if you’d like. So, some companies may call it clincheck. When you’re looking at your clincheck, the first thing that you need to do and the pearl is basically the first thing you do is check that the bite setup is correct. Because every now and then you get a clincheck back and you like to look at it, it’s looking good and you approve it. But you don’t realize actually right at the beginning, the technician who was setting up your case, either because they didn’t have the correct information or the best quality information, ie the setup wasn’t perfect for them, it wasn’t easy for them, they’ve set the case up wrong, which means that the occlusion that you sent them is not quite what is actually happening in the patient’s mouth. So my pearl for you is if you’re doing clear aligner system with a clincheck type of software. The first thing to do when you get your case back from the technician is check the setup. Make sure the teeth are touching correctly as they are in your patient’s mouth. Because sometimes they do get wrong and spotted this before and they get it wrong, then your whole treatment plan from there will not be accurate, it will be completely arbitrary, because it may align the teeth to some degrees, but it will not match the arches up. So that’s my Protrusive Pearl for you today. So let’s join Dr. Devaki and learn all about IPR.
Devaki, Thank you so much for coming on the Protrusive Dental podcast. How are you? [Devaki]
Yeah, I’m brilliant. Thank you so much, Jaz, for having me. I’m so happy and excited to do this. [Jaz]
No, it’s gonna be a great topic. It’s IPR. So this is all about IPR. And the reason I wanted to discuss about IPR is because as I was saying earlier, sometimes when you’ve done something I’ve been doing orthodontic so for a few years now, got a diploma in orthodontics, and obviously you’re a specialist, we’re gonna come on to a little bit about your journey and stuff. But sometimes we’ve been doing something a while you almost forget where you disengage yourself with the struggles that you have the beginning and for me, one of the struggles I had is like IPR, like how to orientate your bur? Which strips to use? How to use them safely? And we know with being a minimally invasive dentist, you almost really worried about cocking it up. [Devaki]
Yeah, I completely agree. I mean, especially now we want to be conservative, you know, especially with IPR and something like enamel. You can never get it back once you’ve taken it away. So it’s something really important you want to plan it properly. You know, if you fail to plan you. Plan to fail, so. [Jaz]
Absolutely once you see photos or once you actually see clinically, some IPR that hasn’t quite gone to plan. That’s a really horrifying scene. So that’s why I’m really happy to be covering IPR. So we’re going to make this the most impactful content, hopefully audio and video on interproximal reduction. I do think with some of my episodes, the video version may have better value. But obviously, if you’re driving or you’re chopping onions or listen to something, then this is going to be hopefully useful to you still, because we’ll discuss a little bit about the history and the evidence base and the sort of risk and stuff but we’ll cover A to Z, and we’ll make it like you said earlier, Devaki, we’ll make it very clinically applicable. [Devaki]
Yeah, exactly. So it helps everyone. [Jaz]
Absolutely. So tell us a little bit about yourself, Devaki. [Devaki]
Okay, so. And I’m a specialist orthodontist. And I actually graduated my ortho training last year, so quite newly qualified in that. I did dentistry at Barts and The London and qualified in 2013. Then I did my foundation year, and I pretty much knew at undergrad that I wanted to do ortho, so everything after that was just ortho, ortho. Want to get in. And as you probably know, it’s just jumping after one who after another. So, after that I did a year in maxfacts. And then I did a year in pediatric community dentistry. [Jaz]
You did the very standard classic route.
Standard, classic route exactly, you know, doing posters, publications, presenting that sort of thing. And because I knew what I wanted to do, and there is a specification of how to do your application, I just followed that really closely. And then I applied for training, I got in and went back to the Royal London again. And so yeah, really enjoyable. And I really love ortho. It’s amazing.
That definitely shows through in your social media channels and that’s why it’s great to have you on, someone passionate about what they do, which is what this show is all about, basically. I want to bring passionate people on with their respective topics. So yeah, it’ll be great speaking to you about this, but one thing I do want to know Devaki is I used to joke and please let this slide, I used to joke before I did myself did a diploma in orthodontics that and take this lightly I said I used to say that if you don’t like dentistry do ortho [Devaki]
Oh my gosh. That’s my joke. [Jaz]
Basically I’ve since changed that view, obviously since I’ve started getting more involved in orthodontics, but it was just a thing because I find that you know if you don’t want to fiddle around with a bit of gum and the matrix band that you want to work more with your mind. [Devaki]
Exactly. You know what, it’s not even a joke, if you ask most orthodontist, not many of them really liked dentistry. And like you said orthodontics is pretty much 90% just in your mind, is planning and then 10% actually doing. So, it’s very clean. And it is like that. It’s just basically like a puzzle. Yeah. [Jaz]
Yeah, absolutely. Well, one thing I have appreciated more for you, you know, especially as in anyone doing orthodontics is that, you know, in restorative dentistry, and even let’s say occlusion and prosthodontics there’s so many conflicting views and opinions. Okay? But they’ve got nothing on the world of ortho. You guys, the ortho world. Honestly, you guys have like some polar camps, who you know, you got the Damon, you got the Damon law, you got the MBT law. Yeah, got the or, you know, the ortho tropics, orthopedic-orthodontics, the people who tell you that if you remove premolar, you’re gonna die, because you won’t get the [opposite] anymore. So you’ve got real polar views in orthodontics [Devaki]
You’ve got extraction is, non extraction is, you know, Invisalign lingual. Yeah, you’ve got so many different teams. [Jaz]
So, it’s sometimes confusing, but it also makes it very interesting. [Devaki]
It does. And you can choose the type of clinician you want to be and and the way you want to practice, so it’s great. [Jaz]
Awesome. Well, let’s talk. Let’s just dive right in, as I say to the first question about IPR. So the mission here is to help those starting out with IPR to do it safely, and even those who’ve done a fair bit of IPR, just to revise are we doing it the best way? Could there be a more effective way? Because there are sometimes more challenging scenarios to approach? So let’s start off with by talking about the methods of IPR, or maybe we should talk about IPR from the beginning as an IPR as an alternative to extraction and what the evidence base is perhaps for IPR? [Devaki]
Yeah, of course. So IPR stands for interproximal reduction. It’s known under many different names. It’s also known as Stripping, Slenderization, Polishing. There’s so many different names for it. They all mean the same thing. [Jaz]
What do you say to your patient? [Devaki]
I actually call it interproximal stripping. I guess it’s the way I was taught. But the way I said to the patients is just like filing in between the teeth or polishing between the teeth. Yeah. And it’s just much easier for them to understand. And actually the way I would describe it to a patient is very different to a clinician. And it’s a method of space creation, right? So if I see a case, and it is case dependent, that has mild crowding, or early moderate, but mainly mild and mild is anything up to four millimeters, I would want to go down the stripping route as method to create space. It’s not just a method to create space, you can use it for various other ways, for example, retracting your lower incisors if you’ve got a particular class three tendency, so a bit of a reduced overjet. And if you’ve got a Bolton’s tooth size discrepancy, so you want to correct that. Got a discrepancy. [Jaz]
Yes. Yeah. Let’s touch on that. Those listening right now who don’t know what a TSD is a Bolton’s tooth size discrepancy, if you just briefly describe what that is because actually, from my orthodontic teaching that I’ve had is that sometimes if you use IPR in appropriately, you actually create a TSD. [Devaki]
Yeah, you’re completely correct. Yeah. And that’s why it’s really worth mentioning it. And so Bolton’s tooth size discrepancies, basically, you add up the mesial and distal width of your anterior six teeth, or you can extend it to the posterior teeth. So the two different types. And if there is a discrepancy of the some of the mandibular widths to the maxillary widths, and there is a figure, it’s I think it’s 91.3% for what you’re what it should be. And if it’s outside two standard deviations of that, then you’ve got a Bolton’s tooth size discrepancy, right? Yes? [Jaz]
My professor who taught me taught me how to really good analogy in a way to describe a TSD. So tell me if you’ve heard of this one, it’s like the foot and the shoe. So your shoe has to be just a little bit bigger than your foot, okay? For it to fit, snugly and perfectly. But if either your foot is too small, or your shoe is too big, or your shoes too small, and you know your foot is too big, or vice versa. And that is a discrepancy. And so either if you’ve got your maxillary teeth too big, or your mandible what and it could be various combinations, but it’s not going to fit together, you’re not going to get the right overjet. [Devaki]
Yeah, exactly. And that can present. So if you’ve got too much tooth tissue in the top, you’re going to have an increased overjet, for example, too much tooth tissue in the bottom, you’ve got reverse overjet, you’re going into a class three kind of bites. And that’s so important. I mean, one of the things you need to consider when you’re aligning teeth, if you don’t want your lower teeth to procline, you don’t want them to come forward, you want to maintain that position. It’s so important for stability too, so that’s why a bit of IPR helps maintain your lower incisors, as well. And so yeah, there are three different ways you can do IPR. You can do it with a dental strip, abrasive strip, or a diamond and crusted strip. And you can also use a rotating disc And you can also use the bur. So there are the three kind of main ways and there have been a lot of more developments on those, for example, oscillating hand pieces and that sort of thing, but they’re predominantly the three different areas in which they’re used. [Jaz]
Orthodontists have a lot of breadth of evidence on various things like I know there are some studies looking at the fact that but if you were to pre stretch some elastic before you apply it, does it make a difference or not? And like you don’t even like look at the minute details. So is there any evidence to suggest that one way or one method of IPR is superior to another? [Devaki]
Most of the evidence is about the effect and stability of IPR. There isn’t really I’m haven’t come across any studies showing the different types of IPR. And I think that is basically case dependent and also the you how comfortable the user feels with using these methods as well. And, but there is plenty of evidence to suggest how much IPR is appropriate. For example, Sheridan in 2007 said 2.5 millimeters for that anterior five contacts and I think it’s 8.4 millimeters for the buccal eight posterior contacts is an acceptable amount. And there have been studies to show that anything more than 50% of the enamel thickness can be detrimental to the tooth in terms of developing decay and periodontal problems. So that’s why anything less than 0.5 millimeters is deemed acceptable. [Jaz]
Is there any point, so that’s great. So take home message is if you’re in and around 0.5 or less, you should be okay as a whole. Obviously, there are other tooth morphology issues we’ll come on to later. But as a general rule of thumb 0.5 and below is fine. Now I once had a case where I had a lady who her upper, her main complaint was that she didn’t like her upper central incisors, they were too big. And the width of her upper central incisors per tooth was around about 10.3-10.5 millimeters each. So that’s like a megadontia category. So in that case, I actually want to for my clincheck, for aligner case, I requested a bit more IPR than what I would normally do to help me overcome this issue. Is that an acceptable thing to do? In certain cases? [Devaki]
Yeah, I think if you’ve got a tooth, which has megadont, then that is acceptable. And obviously, it can be used to recontour teeth, if they’ve got unusual morphology, and it’s also optimizing aesthetics, right? So your central is an aesthetic zone, you want to give the patient the best result possible. But then you also have to consider the shape of the tooth. So McLaughlin Bennett described three different shapes of teeth. So you’ve got triangular teeth, and rectangular teeth, or barrel shaped teeth. And if you’ve got a parallel tooth, it’s not really advised that you what I mean by parallel is a rectangular shaped tooth. It’s not really a [Jaz]
maximal area of contact between the teeth
Exactly. Yeah. And IPR in those sort of teeth is not really advice. Whereas if your central is kind of triangular shaped, then you can afford to take away tooth tissue near the incisal contacts. So it would lend itself better.
You had a diagram, I believe, to show this. [Devaki]
Yeah, exactly. So excuse poor drawing. [Jaz]
Fantastic, it’s way better than I do it, honestly. [Devaki]
So here’s an example of some lower incisors. And these teeth are fan shaped, so triangular shaped. And here, this red area is where you would carry out IPR. And you can see that we’ve taken away a lot more tooth tissue, and incisally relative to the gingival area. [Jaz]
So the tooth on your right was the triangular one, whereas the one on your left is the rectangular one. Yeah? [Devaki]
Exactly. So you can see how it affects the amount of enamel you take away. [Jaz]
Big time. [Devaki]
But then imagine that tooth tissue removed, then you’ve got parallel edges, you would then use that to relieve your crowding and then move the teeth together. But then I think it’s also mentioned, good to mention something to your patients and also for us to know as well is black triangles. Because obviously, the as we get older, and we suffer bone loss and migration of the gingival tissue, we are going to have black triangles, and patients often notice it as the teeth align. Because if you’ve got overlap teeth, and they’re aligned, you’re going to start noticing these things. So and that’s another case where IPR can help if you have the fan shaped teeth. [Jaz]
I’m a huge fan of using IPR to detriangularized teeth, and to get rid of black triangles. And it’s a great thing to do. And a term that I actually learned from Tif Qureshi years ago is PPR. So it’s Predictive Proximal Reduction where, you know, you’re doing it in advance so that as the teeth move in the correct position, aligned position that you’ve already accounted for that. So it’s a great thing to plan in advance, so that you can actually remove the amount of enamel that you need to do to get a more rectangular appearance and therefore get rid of the black triangle. [Devaki]
Yeah, exactly. And, I mean, I never tell a patient that I’m completely going to get rid of the sphere. Because you never really know. And you don’t want to take, you don’t really want to take away. If you have that fun shape, you can’t take away the tooth tissue which is [further] gingival. Right? So I said I always say I can [Jaz]
If you’ve got the parallel mean, you’ve got the barrel shape to that. Yeah, [Devaki]
Yeah, that’s when it’s difficult. That’s when I say I can’t, because if they’re parallel, you’re just going to end up removing quite a bit of tooth tissue. And even to the extent we could traumatize the gingiva, so. [Jaz]
And you’re completely right, communication with these patients. So don’t over promise because it’s not 100% predictable. If you can get rid of them or not. You can say I’m going to try. And this is what you may be end up with, but I’ll try my best and let’s see how your body responds. But the other thing is that, you know, you learn this early on is that if you don’t want the patient about black triangles, then you’re really fighting a battle. And the best way I find is that when I show them a photo of their crossed over tooth, I say that can you see that your teeth are squashing your gum? Your gum is squashed. So when your teeth become straight, your squash gum unfortunately doesn’t grow back, you’re going to have a area where Spinach will get stuck. Can you imagine what I’m saying? And all they all Yeah, I see. [Devaki]
Yeah, exactly. And it’s nothing you’re doing wrong. It’s basically their anatomy. So if you explain, you know, this is where your bone sits, and this is where your teeth sit, and there’s a void, and that presents itself as a triangle and they pretty much understand. [Jaz]
And as a restorative dentist, I’m happy. And I really like using the bioclear matrices to close these back triangles. So sometimes where it’s where you see that it’s going to be difficult to close fully, then you could tell the patient that look, there may be some additional procedures you may require afterwards with composite or whatever, to make sure we can get the full closure that we want. So it’s often unrealistic say that orthodontics alone will sort it but obviously is case dependent. [Devaki]
Yes, it’s case depend. But I completely agree. You’re right. And it’s good to have that alternative option. [Jaz]
Brilliant. So now we just we touched on the three methods of IPR. Which do you prefer? [Devaki]
I personally prefer the abrasive, the diamond strips. Because [Jaz]
Can you show us which ones? Can you show the listeners? [Devaki]
Yeah. So and I normally buy an assortment. So this is single sided diamond, and the color is yellow. Okay? This is the finest, it’s extra fine. It’s then followed by red, which is fine, and then blue, which is medium. So normally, I would always suggest if you’re trying to carry out IPR, you go in first with the serrated metal strips, because that helps break the contact point, then I would use a yellow diamond strip like this. And to go in and kind of see it bit like floss when you see it around the tooth, and go up and down. And then the other way, and then I would move on to the red and the blue. And then you measure it’s always worth measuring how much you’re taking away with a IPR gauge. So I think I got this from Henry Schein or [Jaz]
I mean, I know a lot of orthodontists who have just been doing it for so long and complains that they just eyeball it. I personally find that I’m much happier to use a gauge. It just is very scientific. It’s very proper. I like doing it. But have you got any tips? Because look, that gauge is you can’t always use it. Now. It’s a great opportunity for me to show you that case that we can discuss some difficulties you may have with IPR, we can actually discuss this case. How would you plan that IPR? So let’s let’s do that. Okay, great. So this patient came in with crowded lower anteriors main complaint. And there we are, I’ve been a good boy, I haven’t done any more than 0.5. Anyway. So in that scenario, let’s just pause at that, in that scenario, once you’ve removed some enamel on here, I might use something like a Sof-Lex™ discs, a coarse Sof-Lex™ discs to just remove some material. And above the strips, I certainly wouldn’t be using burs in this case, because I think you’re just contacting the the gingival area not actually doing anything higher up where you need to do it. Is there anything? In this case, Is there anything different you do and also in this instance, you may not be able to use your gauge, right? [Devaki]
You can still use the gauge, I find you can still use the gauge. Because the way I do I don’t do it all in one go. So I spread out my IPR and especially when you’re planning your clincheck, you have to think of each stage as a different stage in its own right? So you plan, for example, we know that your lower left two and your low right one needs space. Right? So you’re gonna have to do IPR adjacent. So that’s where I would start off doing my IPR adjacent to those teeth that I could then bring them in. And I think you’re completely right. I mean, you could even use something like a separator to be able to facilitate access for IPR, and then use the strips and then I know a lot of my colleagues, they start with the strips and then they will use something like a mechanical IPR system or the [ ? ] disks. [Jaz]
I think what I found useful in cases like these is to use a measuring device. I’m trying to think of it is a very normal measuring device. You know, the tools the, in this case, I use like a digital caliper to measure beforehand. And then when I use my Sof-Lex™ discs, or maybe even a bur very carefully under high magnification, just remove that sort of the incisal pathway is a bit more triangular, and then measure it again. I find that sometimes in my hands can work better than using the IPR gauge, because I just find in between that lower left two and lower left one, I might find it quite difficult. It might be like an angle it might not be like, especially after the first visit completely sort of adjacent to the tooth. [Devaki]
Yeah, no, yeah, they are. They can be tricky. You have to put them in them the certain angle to get down, because especially in between their laterals and their canines, okay, canines are so bulbous. So you can have a really sometimes quite a tight contact width there. [Jaz]
And what are you hoping to feel with the IPR gauge? I mean, should there be should because sometimes you try and put it in gently and you won’t go through. But if you just put a little bit of force, it will go all the way down. So my understanding is that how they floss should feel so like, you know, you have to be a little bit tight, that IPR gauge, it’s okay to just force it a little bit, ehereas some people have said that actually, there should be no resistance, you should have to go all the way down. So which is the right way? [Devaki]
I could liken it to how floss feels when you’re taking it through a contact point. [Jaz]
A little bit of a nudge. [Devaki]
Yeah, but not to the point where you’re, you know, ramming it down, then you haven’t done enough. So normally, I normally spread out my IPR. So do about point two, for example, at a time. So if we look at these, I’ll always start by getting the 0.1 in. And once I know I’ve got my 0.1 in, and the 0.1 is so thin, you know, some people have the space between their teeth already. And then after that, I’ll go 0.2, and you can even get other ones where they have 0.15, 0.2, 0.25. That’s how I would normally do it. I actually really like these. I think it works really nicely. [Jaz]
So I think it’s a really handy tool to you as well. Completely agree with you, something official test. Yep, go for it. [Devaki]
Okay, there’s no space in there. But either you go through this way, or you’ll go through downwards. [Jaz]
Is it the same thing. Yep. By the way, should be the same. [Devaki]
Thank you for that. It’s really handy to see. So just to go this case. So yeah, that’s how the clincheck, obviously, clincheck is cartoonodontics is not real ortho. So always don’t compare to real life. It’s just a guide. Anyway, we got this through one round of aligners. Okay, alignment. So far, we’re just going to do some additional aligners to get the torque correct. And you’ll see here the asymmetry of those incisors as well. But it’s not a bad way. So it’s pretty good result, patient was chuffed. The patient actually wants to stop now and I’m like, “No, no, no, it’s not perfect yet. Let’s just get that perfect, and I will be happy.” So if this was your starting position, Devakin, if this was your starting position, and let’s say there was a space requirement to remove 0.5 millimeters, here, I might then be happy to use a bur and in my hands, I’m happy to do 0.3, 0.4 per se at the first day, and then just do a little bit as we go along. I know my Principal at Richmond, he’s very happy to do as much IPR as possible, where the contacts are already straight. What are your thoughts on that? [Devaki]
I always think it’s better to be conservative with your IPR. You know, after you’ve taken away that enamel, you’re not getting it back. And you also have to think about the aesthetics, what’s it going to look like. If they’re going to look like tombstones. It’s not going to be nice for the patient. So and I prefer not to do my IPR at one go. I like to stage it because teeth are continually moving. And you need to forward think and think, where are my teeth wanting to go and then do the IPR to facilitate and create space for them to move, if that makes sense. If you do it all at the beginning, you could lose space and space is at a premium. So especially with IPR. So you want to be really, really careful. [Jaz]
I’m happy and I respect that because that’s the beauty of dentistry, you know, everyone’s got different opinions and different ways to do it. So you’re in the camp that you’d like to do it sequentially. I am quite case selective. Some cases, I’ll do it sequentially. Other cases where I have to admit, if I’ve got a beautiful straight contact, then I’m maybe happy to do a bit more, but I see your point about them like tombstones, I think in clear aligners to get away with it more than it fixed. [Devaki]
Well, to be honest, in fixed Normally, we wait until the teeth are aligned and then carry our IPR. So it’s a little bit different and there should really be a difference, because whether you’re doing fixed or Invisalign, you should plan and treat the same. But I also like to mention that it’s really worth when you’re planning that you consider your rotations because I always correct my rotations first before any IPR because you always will gain space from derotating teeth. Otherwise, you might be left with too much space at the end then you then have to close [Jaz]
I’m just trying to visualize that. So a central, an upper central incisor if an upper central incisor is rotating, it will, usually require space. Right? [Devaki]
Yeah, Sorry, what I mean by that is your premolars and your posterior teeth. So yeah, sorry, that’s confusing. posterior rotate teeth will give you space. Anterior rotated teeth are crowding. They need space. [Jaz]
So and just leading on from that. In those scenarios where And you’ve got those barrel shaped or parallel contacts and you want to avoid IPR, then maybe in those cases, if it’s still a mild case, you should be looking towards expansion. Arch development. Is that is that how you’re looking to achieve your space? [Devaki]
Yeah. So if you’re going the non extraction route, you want to be thinking about things like expansion. Now, we know that expansion is a great way to achieve space creation. But it’s also can be quite inherently unstable, especially in the lower arch. You don’t really want to be expanding the lower canine to canine and so there’s lots of studies on that from [Little] and others about how you’ve got a higher risk of relapse if you expand the lower tooth canine width. So you want to keep that the same. But then you can expand more on the premolar [Jaz]
I think there was one about how IPR can actually improve your stability. Do you want just touch on that? [Devaki]
Yeah. And so there has been research to show that IPR can even help stability post treatment, [ ? ] suggested that if you have parallel edges, then there’s less chance of contact slippage. So in theory, your teeth should remain stable after treatment. And, and I can even in if you’re using common sense, that makes sense, right? I mean, if you’ve got parallel, [Jaz]
if you’ve got more contact surface area, it just, there’s less on to them come away. [Devaki]
Yeah. So IPR is even being used as a reason to achieve stability in cases like that as well. Okay, so here is a patient who had quite significant crowding, you can see that she probably has about five millimeters of crowding. And it’s displayed in the anterior region. But because it is quite significant, it’s also extended up to where the pre molars are. So I actually did two plans for her, I did a plan where we did a lot of IPR and an extraction of a lower central incisor. She didn’t want an extraction at all. So hence, we’re going with this plan. But we can see if I’m just taking it through, there’s a lot of IPR at the beginning. That just because it says 0.3, I might not do the whole 0.3 right at the beginning. But I will always make a note of how much I’ve done. And I think Medical legally that’s really important, as well [Jaz]
Yes, it’s gold standard. [Devaki]
Yeah. So I use my gauge, I even up the contacts, the teeth will then start to move. And you can see that it’s been planned so that as the teeth need it, that IPR is taking place when it’s highly highlighted in yellow. [Jaz]
So and you’re using your the Devaki approach of sequential stripping as you go along? [Devaki]
Yeah, exactly. [Jaz]
Any deviation in this case, for example, that lower left premolar and molar if you just go back to when it was a bit crowded. So yeah, it tells us it always between the two promoters. So that’s a tricky one. Because if you start, if I also start stripping the mesial surface of that lower left second premolar than actually, that would be the buccal, that would eventually be the buccal surface, right? If I started if I just put a strip there, and imagine I put a double sided strip there, for a while, you’re actually removing it from the buccal. That’s not where the contact is. So in that case, I’d be more inclined to get my Sof-Lex™ discs out and actually disc, the mesial surface, is there a better way to do it than that? There’s a different way? [Devaki]
Yeah. So Alternatively, you could use a really fine non cutting bur. And the bur I would like to use, and I will only use those posteriorly. So anteriorly, I’ll just use the strip’s only, because I’m more control, I can protect my soft tissues with proximal [inaudible]. And you can also use suction to protect your soft tissues. But posteriorly I’ll use if I need to take a significant amount away, I’ll use the bur and the bur I use is then strips. This is the bur. So this is from top dental. But you can get these from various other suppliers. It’s non cutting at the bottom. And the diameter of this is 0.3 to 0.4. So it’s giving you the amount that you want posteriorly, some other flame shape burs are more than that. That’s why I don’t like to use them. And I have less control with here. I mean, he’s using this anteriorly but I would use it possibly really. [Jaz]
Yep. Let’s just put your hover your mouse over that photo again, the way that the this clinician is using it now. There’s no right or wrong because that is what works in your hands and your experience. So let’s start with that there’s no right or wrong. Now some people and I’ve seen some videos back when I was had my first IPR case coming up some years ago and I was looking at Okay, how am I do IPR, I was watching all these videos and stuff and asking different clinicians. And some would say hold the bur like this and go up and down. Okay, whereas others were saying, if you do that and you slightly deviate you make a nasty shape, a nasty little tooth [Devaki]
A ledge. [Jaz]
A ledge. A negative ledge in that way. So then the other way to do it would be hold it like so basically and then just do like little brushstrokes, which is what I do most 99% of time that’s what I’m doing. Do you have a preference? Because obviously, you’re doing posteriorly. So, I mean, going near the gingiva and going up for me, it’s it that angle, it doesn’t make sense to me as much. [Devaki]
Yeah, I mean, I’d have to agree with you that I prefer to go parallel to the tooth rather than perpendicular with a bur. [Jaz]
Yeah, but if you can get the right access, I’m not saying it’s the wrong thing to do. But if you can get the right so if you have any experience doing it, just be very careful use high magnification, it would be my opinion. [Devaki]
Yeah, I completely agree. I mean, I’m going incisally then downwards parallel to the tooth just enables me to remove more tooth tissue where I need it, where there’s more incisally. I don’t really want to remove as much gingivally. And although it’s a non cutting bur, I’m just trying to think about where I want to remove, [Jaz]
What do you mean by a non cutting? [Devaki]
So and these burs, the non cutting at the tip [Jaz]
At the tip? [Jaz]
Brilliant. So is there any technique to hold it? For example, I’ve seen some clinicians go really, really fast. And that’s the way to do it. Others put a lot of sustained pressure, any tips you can give us? Is there a wrong way to do it in certain holding it whatnot? [Devaki]
I think, I don’t know if there is particularly a wrong way. And the way I do it is I do it pretty much like in this image, I’ll bring it down, and I will see it around the tooth bit like floss. And then I will do this. Like that up and down. And just to make sure that I’ve removed an equal amount. Now some people criticize trips because they say they’re time consuming etc. But I feel like with the strips you have the most control. And it happens really slowly. So chances of any soft tissue trauma or anything like that are reduced. I feel. [Jaz]
I agree with you, I think these strips have been a constant source of repetitive strain injury for me. It is a controlled way of doing it. But yeah, sometimes when you’re doing like 0.3, or with the scripts, and you’re really there and the patient’s like, when’s this gonna end? So yeah, [Devaki]
but that’s when I think you want to then go in with your disc or your file with [Jaz]
Yes as na adjunct one, you can mix and match. It’s good. [Devaki]
Yeah, exactly. This is a good entry, and then you can follow on with those other ways. [Jaz]
Do you apply fluoride as a rule, or every time you do IPR? [Devaki]
So there are mixed views on this, there’s some evidence to say it’s good to reduce plaque formation and things like that. But other evidence to say it’s unnecessary. I personally don’t use fluoride, unless someone is reporting that they get quite sensitive teeth to me beforehand. I don’t use fluoride, I just recommend them as sensitive fluoride toothpaste. And [Jaz]
I’m in the same camp as you. So I used to apply fluoride all the time, until I looked at the evidence and suggested actually, the slider is going to do a good job of remineralizing it, and you don’t need it, and the other thing is that, what message are you sending to the patient, if every time they come in and you’re like, we have to apply the flouride, I don’t eat for half an hour or whatever. They will be “Oh, my enamel is was getting weakened?” They’re having to do all this adjunctive stuff. So it sends a wrong message I think so I do it for sensitive patients just like you. [Devaki]
Yeah, and even in the evidence, that person did a 10 year follow up study and people had very minimal risks associated with it, you know, since there wasn’t much sensitivity, though, periodontal or caries risks associated with it. So I just think, you know, it’s case dependent. Has the patient got good oral hygiene? Have they got healthy gums? If so, then [Jaz]
that’s the most important thing. [Devaki]
Right. Cool. I’m gonna check for any more questions. I think we’ve done really well. You’ve definitely pretty much answered all the questions I had. Is there anything that you think we want to cover to make it a really, you know, cutting edge resource excuse upon, for IPR? For Beginners? [Devaki]
I think the most important thing is planning. So it’s really important to take the time at the beginning to assess how much crowding you have? Where is the crowding? Look at all your factors, what is my tooth shape, like? What are the aesthetics like when the patient is smiling? How much teeth have showed, the display? I mean, a lot of this information you will get from your assessment, and then when you’re planning don’t just follow what the contracts telling you. Although Invisalign cloud billions of pounds into their system. And it’s a really great system. I love Invisalign. But it is about the clinician planning the case. And that’s one thing I think is really important. So think it through, you can tell Invisalign, I want IPR at this stage. And that will make you an even better clinician. And if you put your take on it, because you are the person planning the treatment, Invisalign is just a tool. [Jaz]
Brilliant, I love that. And one thing you just reminded me of is you mentioned earlier about whether you’re doing fixed appliance or Invisalign, the movements and the stages of the movements are very similar, if not identical. So, in fixed appliance, you’re waiting for the contacts to become parallel, uncrowded. And then you’re doing the IPR whereas when I’ve been on the the Invisalign courses before they’re very scared about round tripping. Can you explain why? Why Invisalign folks, scared of round tripping, where actually in fixed appliance where we are around tripping a lot. [Devaki]
Okay, yeah. Well, I mean, my professors would kill me for this. But I mean, in theory, you should never round trip ever. [Jaz]
Minimize round tripping? Of course, yeah. [Devaki]
Yeah. Basically, in fix, in theory, you shouldn’t be [married to ping] either, because you should be switching back your wires controlling your AP arch links and things like that. And so, round tripping isn’t a good idea. Whatever you do, because you’re proclining teeth, you’re putting strain on the gingival tissues, you should all show also be considering if that patient’s got to then gingival biotype. And, again, this is where people just accept the clincheck. But they don’t realize or may not take consideration into one of my patients’ gingival tissues like. Can I just leave them changing their aligners every week without monitoring that? So that’s really, really important. But I completely understand what you’re saying, with fixed treatment, your NiTi wires, the teeth are tipping everywhere. And I’m sure if we actually then put that on a clincheck, we would see a bit of forward back movement. But with Invisalign, the beautiful thing about it is you can digitally see where the teeth are going to go. So because of that foresight, you can plan for it not to happen. And that’s why I love the super imposition tool. Because I say, and I specifically say to Invisalign, unless my teeth are retrocline and I can afford for them to come forward as best I can say to Invisalign do not procline the lower incisors. And then, if there’s too much, IPR, lower three to three, I’ll take it back to the premolars. Premolars a bulbous, you can afford to do that. [Jaz]
Perfect. So I think the answer well, so we want to ideally minimize, round tripping where we can and with the the beauty of clincheck virtual plans, we can stage IPR in a way that will have to mean less IPR, even though they’re not fully aligned just yet, but you can split the strips, I think it gives you that ability to take away a little bit per time. And I’ve just realized something that we didn’t do is that we talked about round tripping, but there may be some young dentists out there who don’t do any ortho you’re just listening in, and they’re maybe thinking about starting over. And they have no idea what round tripping is. I didn’t know what round tripping when I was an undergraduate. And maybe you did because ortho was your passion area. Can you just explain round tripping? [Devaki]
Yeah, so round tripping is basically as the teeth align, there’s a tendency for the lower incisors or even the upper incisors to procline, and that is called tipping. And in ortho, you want to torque the teeth to enable the roots to be in a stable position. So then what ends up happening is after your NiTi wires for example, you go into more rigid wires, and the teeth end up coming back. Because you’re then torquing them because you’re moving the roots in the right position. I don’t know if that’s a good explanation. [Jaz]
It’s fine. So it’s coming forward. And then coming back again, you’re going around again, [overlapping conversation] Constraining exactly was in common. So why is it round tripping bad, it’s gingival. The supporting structures, maybe taking a bit of a beating. [Devaki]
Exactly. And you always want to move teeth in bones, if you’re just, if they’re just proclining. And there’s a risk of you know, God forbid this would ever happen. But perforating the cortical plate, etc, [Jaz]
getting gingival recession areas and whatnot [Devaki]
Dehiscence and that sort of thing. And this is another really important tip is if you do notice any recession, and in your assessment, it’s really worth noting it and measuring it and documenting it because sometimes the recession can get worse as the teeth align. So [Jaz]
That’s a really good point. I think our photos help us but it’s medical legally really good to measure it with a Perio probe or something because every orthodontic patient I’ve ever had, who had significant or moderate to significant recession to start with, but they were periodontally healthy and we’ve chosen to do orthodontics. You know what they all say? They all email me especially not every I’m emailing, I’m checking in on patients. And they all say, “you know what, I feel like my recessions got worse.” In fact, some of my whitening patients, okay, I just give them whitening trays, which are nowhere near the recession, because I want to keep it away from the root surface. And they come back. So yeah, my teeth are whiter. But I think the whitening cause my recession. But what they do is just, they’re more aware of the recession now and some sort of teeth are aligning there, you can see the areas where you couldn’t see before. So a lot of the times patients are thinking, Oh, my God, my recession is getting worse or whatever. But really, it’s probably not happened. But if it has, you need to make sure you’re on top of it. And that’s where your documentation comes in. [Devaki]
Yeah, I completely agree. And, you know, 9 out of 10 patients, they’ll come and say, I don’t like this. And like you said, as the teeth of straightening, they spend so long looking at their teeth, they’ll find other things that don’t like, so it’s just always worth gathering this information at the beginning, you know, as much as you can. And so you can exceed the expectations rather than under deliver. [Jaz]
That’s a really good communication point. That’s one thing. The way I like to do, Devaki is when they say their main complaint, and then I say to them, okay, and what else? anything else? and then they might say something else. If you didn’t ask them that they would have never said that second thing, and then you keep going, you keep asking until he has nothing more to say. And then I sometimes tell my patient that okay, the reason I’m pestering you is that, although you’re unhappy about this main thing here, I often find that when we sought that one main thing out, then you know, just all the other myriad of things. So it’s really important that you know, you take a good objective look, obviously subjective as well, because beauty is in the eye of the beholder, and orthodontics oftenly say that. But it’s a great communication point, you raise that to have a chat with the patient in that way. So Devaki, thank you so much for coming on and helping us about IPR and getting the nuances and how to hold the bur and the different methods and a brief overview of the evidence, really appreciate it. [Devaki]
It’s been an absolute pleasure. Thank you for having me on here. I’ve really, really enjoyed it. And I hope people find it useful. [Jaz]
I’m sure they will. Thanks so much. [Devaki]
Jaz’s Outro: So hope you enjoyed that chat with Devaki all about IPR. Thanks so much for listening all the way to the end, as always, really appreciate it. If you’d like to suggest a topic, please get in touch. Follow the Facebook page or the Instagram page and let me know how I’m doing. I want to put on some good topics. I’m enjoying myself. Look, I love podcasting. I love learning from my guests. So it’s a hobby of mine and you find it’s bringing value to you. And please share it with your friends and suggest some topics that I could cover. Thanks so much once again.