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As you get more experienced with clear aligner therapy you learn a universal truth about those pesky lateral incisors that will refuse to extrude! I am joined by Dr Robin Bethell from Aligner Nation to help us learn more about the use of Elastics as auxiliaries for Clear Aligner protocols.
Need to Read it? Check out the Full Episode Transcript below!
Protrusive Dental Pearl: The Bethell IPR Technique! Click Here for the Video of how Dr Bethell uses the bur for IPR
Interestingly, Dr Robin Bethell has not used intermaxillary elastics for over 3 years. He primarily uses them for vertical movements. I personally have used them extruding lateral incisors, which works very well. Here is the video to share how to extrude lateral incisors with elastics:
We also discussed:
- Common causes of Posterior Open Bites during aligner treatment
- How to manage Posterior Open Bites (the key is diagnosis)
- The role elastics play in clear aligner treatment
- Dr Bethell’s views on GDP Orthodontics
Here is the link to the evidence base Dr Bethell referred to
Be sure to follow Robin Bethell on Insta and check out @protrusivedental for more
if you enjoyed this, you will also like Comprehensive vs Compromised Orthodontics as part of the Straightpril series!
Click here for Full Episode Transcription:
Opening Snippet: Over the years i've realized what is best for me to do and what isn't. I think that a lot of general dentists get in this and because invisalign looks like magic. It truly like it's amazing that plastic can do this. They get in over their heads a little bit and i can see why some orthodontics get upset...Jaz’s Introduction: Hello, Protruserati, I am Jaz Gulati. And welcome to another episode in this orthodontic month. This episode is focused on Invisalign and elastics. Like one of my most popular episodes before was IPR, like getting into IPR and the nuances of that. And I feel that one of the biggest pain areas of dentists who are getting started with aligner treatment or even experience with aligner treatment is using elastics. Now whether it’s to extrude lateral incisors, which is the way that I learned to use elastic with aligners, or to use them in intermaxillary. So from across the arch, so for example, class two or class three elastics, we’re going to cover that with someone really cool. His name is Dr. Robin Bethell. He’s based in the US. He runs the Facebook group aligner nation, which is just phenomenal. You guys should totally follow it if you’re not part of that already. And I’m going to ask him the nitty gritty details. Now, this episode is an amalgamation or a marriage of part one and part two, because when we first record, it was going really well. But then there was a storm in Texas of all things. And this storm in Texas meant that we had to cut short because he was having signal issues. So we rearrange, and a few weeks later, we thought we’d take two, but the biggest shocking thing you might hear today is the fact that actually, should I ruin it or not. Should I continue shall continue saying I’m saying, Okay, fine. I’ll give you the spoiler. Okay. But there’s more to it in this episode, I promise you, but Robin basically said that the wealth of evidence that we have, and the position statement we have is that intermaxillary elastics, like class two and class three elastics, they don’t really add very much into your aligner treatment. So that was a massive shocker. Because you know, every time I have a guest on a podcast, and I prepare like three or four questions, my first question was, Okay, tell us about elastics and aligners. And then the second and third and fourth question was like the nuances, okay, which ones do you use for class three? And lastly, how do you stage it and that’s quite kind of stuff. But can you imagine how shocked I was one of the first question he says, Now, don’t bother using it. I haven’t used it for three years. I was like, What? It’s, that’s crazy. The protrusive dental pearl I’m gonna share with you is a video technique, like the most commonly asked question I get sometimes based on the IPR episode is Hey, Jaz, can you just like make a video of IPR and never get around to doing it? Because that was like a big pain area when I was starting using burs for IPR. Like, as a general dentist, like I love enamel, you will love enamel right, and won’t be as conservative as possible. So when I got to terms of using a mosquito bur, I was really worried initially is Oh, my gosh, you know, I’ve seen some example radiographs for where it’s gone totally wrong, right. So I’m going to share with you the guest we have today Dr. Robin Bethell. His ‘Dr. Robin Bethell Texas IPR technique’, which is basically using red mosquito bur and it’s just a way he does it like if you’re starting IPR with burs, if you watch this video, it will give you a bit of clarity. And you still need to use magnification you still need to be careful, I think, but sometimes by watching someone else do it. But in the video is good enough quality that I think you get the gist of it essentially if using the bur in a certain way, and then doing the rest of it in what he used a space file, sort of strip and you can use any sort of IPR strip you want. But you open up the embrassures with the bur, and in the final bit of enamel use IPR strip. Hopefully I’ll get to video at one day as well. But since Dr. Robin Bethell, our esteemed guest today has already done that hard work for us. I’ll be more than happy to share that. So Dr. Robin, thank you so much for all this amazing content that you make. I’m so stoked that we have him on today. So this was done live guys. So excuse any shoutouts. And again, if you’d like the live stuff I’m doing, do check out the facebook page, which is a protrusive dental podcast Facebook page, if you’re not already following the Instagram, it’s @protrusivedental. So I’ll catch you in the main episode. And I’ll see you in the outro.
Main Interview:
[Jaz]Thank you Dr. Robin Bethell. You’re based in Texas I believe we’ve never met before. But I appreciate you so much for agreeing to do this. Because what you set up with the aligner nation community is just brilliant. I’ve been practicing this line for about four years now. And yours has been the best resource for aligners. I found some of your videos, your energy on there, your level of education, it’s just great. So thank you to producing all that stuff. But tell us a bit about yourself, where you practice, how you got into aligners and how you become one of the top Invisalign providers in the US. I believe [Robin]
That’s a killer intro and thank you. I am in Texas. I went to school in San Francisco at University of Pacific. I was trained in aligners by Robert Boyd back in 2006. And I became a Invisalign provider. I’m gonna say that in quotes, because there’s not a high standard in the United States to become an Invisalign provider. You just take a weekend course and they say you’re ready to go teach you how to take impressions. [Jaz]
It’s the same in the UK. [Robin]
Yeah. And it’s part of the great thing about aligners in this era, and also the problem, and that we are so naive to how they work biomechanics tactics, and there’s not a lot of literature, clinical literature to support a lot of the things we’re taught. And so we’re kind of in this new frontier, we’re discovering things as we’re going. And I was definitely trained in orthodontic fundamentals, and that gave me a foundation to go out and feel confident in treating people with aligners. And I was, let’s just say, rudely awakened. My first case is my father. [Jaz]
Your first aligner case or your first orthodontic case like with the fixed appliances? [Robin]
Aligner case. Yeah, it was my dad, and it went terribly wrong. Yeah, I trusted that. [Jaz]
Tell us the details. What went wrong? What was it the classic posterior open bite afterwards? What was it? [Robin]
A little bit of everything. My biomechanics setup was awful. I trusted the Invisalign assist program at the time, you submit your impressions, and they give you a clincheck. And you’re supposed to, you know, submit a new impression every four to six weeks. And he was a class two crowded case. And I had everything from elastics buttons on every teeth that I just said, we’re gonna trust the system, I had no idea. You know what was going to happen and it did not work, teeth didn’t [track] canines didn’t rotate, elastics did nothing. And in the end, he just burnt out and stopped and his teeth just went back to where they were. [Robin]
You know, in 2014, I treated him again, and we got them lined up, his teeth look better than ever. He’s never had aligned teeth before. He’s very grateful for it. [Jaz]
Brilliant. So you shared that very nicely to share a failure, isn’t it? So human of you to share that. And I think with aligners, beginners can make this mistake. I remember the first time I got a clincheck, I didn’t know what to do was okay, this looks pretty good. Does that mean it’s good to go. So that’s a classic mistake for a beginner to make. And then when you learn that, hey, actually, the person at the end of it, who’s engineering everything is not a dentist, you are responsible and you’re in charge. And I think you’ve went on that journey and I think what you’re sharing now everyone on the aligner nation group and stuff, some of the videos you make, I think you might want to set a crushing clincheck. I love the title. It’s honestly your energy and your vibe, and you’re really put yourself out there as a great [edge] going in aligners for me, I’m so excited because most of my meet about 70 to 80% audiences UK based. So for those guys in the UK, I know you’re gonna love Robin’s content. So Robin, we’re gonna dive in to the main theme of today’s episode, which I’m so grateful to have you for is elastics. Right. So I’ve been doing aligners for four years. But I know I’m gonna learned so much from you about elastics. Because a lot of my peers don’t know much about elastics when it comes to the use of elastics in aligner treatment. So it’d be great to get the main fundamental. So if we start with the basic question, what percentage of your patient Robin, are you prescribing elastics for? [Robin]
that’s a great question. And it’s a very important question. In my cases, and I treated last year over 700 cases, less than 10% are in elastics. And there’s a really good reason for that. And not that there are 10% of my cases are skeletal or class one or class two or class three, it’s that elastics when use with aligner systems are only useful and predictable when they’re moving specific vectors or specific to specific vectors. They are not useful in the American Board of orthodontics published there, she made the AAO publish a study in November 2020 saying that, that the success rate and the ABO success of class two treatment with elastics in Invisalign aligners is it really bad, like less than 20% success. So elastics to treat a class two cases skeletal problem, don’t do it. Elastics to extrude a tooth that’s not tracking properly order to give anchorage to the molars while you’re moving the anterior segment distally that can be done. And that can be helpful and provides a specific support system to allow you to achieve those movements. But the main takeaway with elastics is you have to know your diagnosis. And you got to look at the patient’s face, you’re not going to change a patient skeleton by putting a rubber band between an upper and lower arch that’s wrapped in plastic. [Robin]
Well, in these class two cases, then if you’re saying that the success rate of the elastics is not so good. So using class two elastics, can we just rely on the aligners to do that bit within reason. And then the elastics is an unnecessary step? [Robin]
I would say globally? [Jaz]
Do you just use them anyway? [Robin]
No, I don’t use them. If they’re not going to provide a benefit. I don’t use them. And globally there are people are prescribing them unnecessarily. I see it all the time. I think many clincheck go through the algorithm and everyone has to know that Invisalign. There’s two tracks that your cases go through. First they go through an algorithm. Basically, the computer makes a align down the center access of a tooth and it makes all those teeth parallel, and it aligns them up. And it does it in a matter of seconds. It’s just a computer algorithm. And then it goes to a technician and they read your preferences, and they try to modify the algorithm to fit your preferences. And then it comes back to you in the form of a clincheck. 0% of those are right the first time in my practice. So if you have a, you know, an algorithm that makes a class two person with the maxilla is out here into a class one person, the algorithm will kick out elastics, they will automatically put class two elastics on I’ll put a little cutout on the canine and I put a little cut out on the molar or a slit that you can hook elastics to and what you’re assuming and what the algorithm assuming is that you’re going to advance the mandible with the use of elastics. And we know that that in a non growing patient doesn’t happen, certainly doesn’t happen predictably. And as someone that’s growing, yeah, the mandible could grow forward. But that’s a surgical case. And if the maxilla if you do a cephalometric analysis, and you determine that the maxilla is protrusive, it’s too big, you’re not going to get the whole maxilla to you know, come back by putting on some 100 or 200 gram elastics on a case. Now, if you have blocked out canine a three, that’s, you know, you didn’t have room for and you push the teeth out, you expand the arch by tipping the crowns, and you make room for it. And then you hook an elastic on that canine and you anchor it, and you put 100 or 200 grams of force on to pull it down, that will certainly help get the canine to come down. So those kind of cases I use elastics for to close down more. [Jaz]
I’m getting more local factors rather than for what we traditionally would have thought, you know, class three elastics class two elastic. So that’s the take home, they’re basically that actually they are over prescribed maybe by the clinchecks, and they maybe have more of a role in localized movements. Is that Is that a fair way to put it? [Robin]
I think it’s an excellent way to put it, I think that I use them in localized movements only. And if, for example, a great question is, you know, you got a posteriorvopen bite where the bilateral or unilateral you got molars and bicuspids not touching, and people will come back and they’ll see these clinchecks where they have attachments on every tooth or button cut outs and every tooth and they’re trying to close down the posterior. That’s an incorrect use of elastics as well. And I think that what you’re really have is anterior interference. And if you can get the interference out the mandible auto rotate and then get the teeth to come together. It was a poor diagnosis. [Jaz]
That was actually one of the questions that it might just one set the theme for this. So yeah, one common thing is definitely happened to me. And it’s happened to so many people, right, where you finish your cases, it’s typically going to be a class three tendency case where they got crowding, and then you resolve the crowding. And then what you didn’t get enough of was overjet. Because overjet is king, so you didn’t get enough overjet and please correct me Robin, because I trust you far more than I trust myself when I’m saying this, okay, so overjet is king, you don’t have enough overjet. And because just like you said, you have that interference, you have this posterior open bite this is not because the aligners were intruding the molar where as you know, to the extent it’s more because you have that interference, if you create more overjet, you get rid of the interference. So what some people do is they like you said, put buttons and use elastics, like box elastics to extrude it, but what you’re saying is actually even that scenario, let’s ditch the elastics. And let’s actually deal with that interference, is that a fair way to say? [Robin]
It’s exactly how to say it. And then the main point using Invisalign, or whatever aligner system that you use, is you’ve got to know your diagnosis, you got to know your sort of why before you start trusting a computer screen, which is just teeth floating in space in a theoretical system. And I think once people accept that responsibility, Invisalign gets a lot better, a lot more fun. [Jaz]
Well said in the UK, a popular approach and in Europe actually, just a final, a popular way to approach that situation where maybe you have got a bit of a posterior openbite I’m not talking about a crazy amount I’m talking about less than a millimeter is that some conditions, we’ll cut the distal of the canines for the lower aligner and allow like some dahl type movement or over eruption of the lowers or premolars and beyond, and then maybe four weeks later to then just retain at that level, is there a place for that in your practice? Have you seen that work? Do you know anything about that kind of way of resolving? [Robin]
Absolutely. And again, that works. If you have your diagnosis correct. If you have somebody that has a prognathic mandible, and you know, they have that square shaped jaw, they’re mandibular plane angle is not very high, and you just cut the elastics expecting for the molars to [super up], it won’t happen. And so people were like, Well, that doesn’t work. Well, it would work if you had your diagnosis correct. There is this theme and this concept and you know, I don’t even like using this term, because it’s not been proven, but we think that plastic causes passive intrusion of the molars. Now if a patient has a steep mandibular plane angle, maybe that dolicofacial profile that we see, long face and they’ve steep maybe they’re class two. And they’re more force on their molars because the molars hit first and you add a quarter millimeter of plastic to them, thus increasing the force on the molars. Yeah, yes, you could get some intrusion forces on those molars. Yeah, so they get more force on the molar is an intrusive force and the aligners will actually intrude that the molars, and then if you cut the aligners within a day, the molars erupt back and you get occlusion on the molars. So when you have a patient back in your chair, and you notice they have a posterior openbite you have to do some analysis, there’s a lot of different ways to check and understand there are four different types or four different causes for posterior open bites. And the most common sense it is, or the most likely, since it’s an anterior interference, you try to uncrowded the [material] without the overjet. And now you’re just hitting in the front, or you’re trying to create a class two person and you had you had this expectation that you know the mandible was going to move or the maxilla was going to or a class three tendency patient, and you didn’t get any skeletal movement because you’re not going to get any skeletal movement. And then now the patient’s just occluding on their anterior teeth, or you didn’t achieve the anterior intrusion, you’d level the occlusal plane like the clincheck showed and now you’re still in deep bite but the anterior teeth hit that’s the most common posterior openbite and cutting your aligner. So to fix that won’t fix it. [Jaz]
They have to have that. Well I like to think about it is when I’m doing the dahl concept. Essentially, it’s all using that. But if the patient doesn’t have any eruptive potential in the area, it’s never gonna happen. It’s a bit like a patient with an anterior open bite. Why don’t their anterior teeth overerupt naturally and meet because they don’t have that potential to so I think it’s a great way to put it. I’m gonna just go to the next elastic question, which is the most common use of elastics I have ever had to do which is for those pesky lateral incisor so quite commonly, they will not track anymore. So I want to ask you any tips for lateral is not tracking or we just got to accept that that’s the way it is and naturals will always be annoying and pesky in that nature. And can you just talk through and describe how someone might go about the first time they counted it what the steps are involved in extruding a lateral incisor using elastics? [Robin]
That’s a great question. And it’s one that we get all the time. And yes, laterals can be very pesky with aligners. They’re like trying to grab a wet watermelon seed they’re slippery, they’re small, not a lot of surface area. The extrusive force on a lateral incisor First, the biggest tip I have when diagnosing whether or not a lateral needs to extrude look at the CEJ is the CEJ of the lateral incisor where it should be in the face a lot of these clincheck they will move they’ll extrude the laterals to make the incisal edges even with the Centrals when in fact the best diagnosis to me is get the CEJ level with the Centrals or even a little bit lower than the Centrals and then you can bond or add [length] because the the size of the lateral is the problem not the position of the lateral biggest tip I have is don’t extrude laterals that don’t need to be extruded. That’s number one. And when you have to extrude the lateral. Then you have to extrude a lateral. I’m really, really like this smart attachments. There’s John Morton research in the G7 series of attachments. They made this really large active It looks like a smiley face. It’s called a optimized support attachment. And you put that on the facial of an aligner or excuse me, the facial of a lateral incisor and it really helps a elastic engage the active surface, there’s a little dimple on it and you will get a lot of eruptive incisal vector of force on that tooth to help and if you still can’t get it, you can use elastics and I’ve used the bootstrap technique with some success and a bootstrap technique is basically cut the aligner on the facial. You put a little button I like these clear buttons that you can buy on reliance orthodontics, you put a button on the tooth, and then you have slits, you cut little slits into the back of the aligner and you put an elastic, high force small elastic where I was going with that as I hooked the elastic to the front of the attachment that the button that we put on on the front of the tooth and I wrap it around the aligner and then I hooked the elastic onto these little slots I cut out of the aligner on the back and I call it a bootstrap and it applies in adds another 50 grams of force to pull that or extrude that lateral incisor. I’ve had some success with that. [Jaz]
The question I ask is on the fine detail is on the back on the lingual or the palatal part of the aligner, are you making like an L shape is an L shape that you’re making? [Robin]
No I actually I cut two little slits looks like a little v. So if you imagine you’re on the the palatal part and this is the incisal edge I’m looking at the palatal I cut like a slot this way and a slot this way. And I hooked the elastic around that it kind of cinches down Hold on to the distal lingual and then it wraps around to the front hooks onto the button. Okay. [Jaz]
Welcome for part two. Robin Bethell is so great to have you on Dr. And how are you today? [Robin]
I’m doing great. Can you hear me? [Jaz]
I can hear you just fine. A little bit of lag. But I think we can cope with that. Hearing you well though and looking great. So last time there was a storm, there was a storm in Texas. And then we had to abandon the initial bet you gave a lot of value. So I know people be coming back to join this part. So we’re going to spend the first 5-10 minutes just recapping what we covered in the take one and then we’re gonna wrap it up with the tape two. But just remind everyone, okay, well been a little bit about your background, how you got into aligners and what you love about aligners, and are you and I didn’t actually ask you this. Are you limited to aligners or do you do fixed as well I didn’t actually ask that last time. [Robin]
Well, now I’m just doing aligners in our general dental practice. But I started out doing fixed in aligners for many years and I love orthodontics. I somehow feel like I should have been an orthodontist. But I love using orthodontics as a part of comprehensive dentistry now and I work really well collaborate with other orthodontists for a lot of cases. Because really orthodontics is it’s the foundational part for setting people up for lifetime oral health. And it’s a little bit too much to do everything all at once. So we kind of focus on the stuff that I can do efficiently and work with orthodontists for the things that they can do efficiently and better than me. [Jaz]
That’s a really good point. And we might touch on that actually about maybe towards the end we’ll touch on, what is the limit of aligners because I seen some of your cases and I think no way can you do aligners and you seem to be pushing boundaries along with a lot of other doctors are really pushing boundaries in aligners, so it’d be interesting for me to find out maybe towards the end about where does Dr. Robin Bethell draw the line in the sand? Right. So that would be really cool to know, I think everyone will want to know that. But let’s pick up where we left off. You threw an absolute bomb on the last episode, where we started because you actually shocked me because here I was the three four questions I had written down. And you almost raised all my questions, because when I when I asked you, Is there much value in using intermaxillary elastics Invisalign? You said? [Robin]
I said no. It’s it confirms suspicions from many years of using Invisalign aligners and AAO published a paper in October this year, basically saying that elastic used to correct skeletal sagittal plane movements is not effective. Not advisable. [Jaz]
So you don’t do it. Just to recap, you you don’t use intermaxillary elastics for class twos or class threes at all? Or do you? Do you still do it because it makes you feel warm and fuzzy and good inside? [Robin]
I do not do it at all. Not even once anymore. And the last three years, I use elastics. But I use them for other things which we’ll get into, but not for class two class three movements now. [Jaz]
That’s crazy. So someone asked last time Hey, didn’t use it in this situation or that situation. So someone asked last time, do you use it in these mild class three situations to help to retract lower incisors? But the answer is no. Because he just said it. The answer is no. That’s crazy, right? That’s crazy. Let’s see, I use some elastics about probably three or four weeks ago, just before we had that episode. And I felt was okay, I’m helping you. I’m helping. But there we are. You’ve told us that it doesn’t work. And I’ve seen the cases you do. And if you haven’t used intermaxillary elastics in three years, then that’s something to be said about that. So there we are guys elastics in terms of the intermaxillary ones, the ones that go in between canine to molar, molar to canine that kind of stuff. We’re not using it so much and there’s no significant evidence for efficacy. I think Robin are trying to say so let’s get on to when you do use these aligners and we touched on extruding laterals and we will just recap the technique a little bit because you know as dentists we love the nitty gritty details of exactly which elastic to use. How long do you use it for? We love those minute details. But other than extruding laterals? Which other scenarios do you use elastics for in Invisalign, or with aligners? [Robin]
you know, I like to keep it simple with the aligners make it as predictable as possible. And I think the number one use of elastics in aligners in my practice is for vertical movements intruding or extracting a tooth, and usually it’s a single tooth, not an entire arch. Now I’ve seen some doctors do entire arches by placing mini implants or TADS. Like for example, if they want to impact the maxilla move it up, they’ll place TADS and they’ll use elastics from the buccal across to the lingual and an aligner to intrude an arch. Dr. Frost does this with Damon brackets. It can be done with aligners, but you’re getting into some really [uncharted] waters here when you start doing that. But what I like to do is if I have a single tooth like a lateral incisor that I’m trying to extrude and it actually needs to be extruded, and I make that need based on a facial diagnosis. But I’ll put a little button on the cervical third of a tooth and I will either bootstrap it. So take the button put an elastic on, wrap it around to the lingual and attach to the lingual over an aligner to pull it and I’ll share with you the specific elastic that I use for that, or even more effective is a cross arch, where I’ll put a little hook on the lower like a triangle style. So put a one hook on, for example, if I’m trying to move number 10, I’ll put a little hook on like 23, and a little hook on 22. And I’ll make a little triangle with a three eighths inch, five ounce elastic and get some forces to pull that down. [Jaz]
So those are both techniques in, for example that you could use in extruding a like single lateral or single canine like, when would you use the bootstrap technique whereby we’re going to get a little bit more in fact, with the nitty gritty details, but when did use the bootstrap and when we use this, the second technique you mentioned whereby you’re going intermaxillary [Robin]
Well, you’re going to get a lot more force intermaxillary. And, you know, bootstrapping, you got to think that elastic needs to be stretched out for it to generate force, and a bootstrap, you’re only moving it maybe, I don’t know, 10 millimeters to go from the buccal across to the lingual. And if you’re using cross arch, you can get that 20 to 30 millimeters of stretch to get the forces you need to generate an extrusive force. You know, Dr. Sandra Kahn, she published a book and she talks a lot about elastic use in that book, How to pull down those pesky laterals, and canines and things. And she’s a big advocate of cross arch. I’ve used cross arch, I’ve used bootstrap for a canine, I wouldn’t use a bootstrap because you need to generate 100 grams 200 grams of force to get a canine to extrude. Anyone who’s tried to do the, you know, the chain on a wire technique, you know, you got to keep that wire tight. And if you don’t do it tight, it’s not going to budge. So I wouldn’t recommend doing a bootstrap on a canine but a little lateral with little, you know, little roots, you can bootstrap and get a millimeter or two of extrusion. And I’ve had some success, but it’s less predictable than cross arch. [Jaz]
Thank you very much, Robin. So just for those people listening, we did cover a little bit about bootstrap last time. So one way I’ve done in the past, and I quite like the bootstrap way better than Robin described is that the way I’ve done the past is on the front, we have a button just like Robin suggested. But on the back I made like a almost like a L or a T shape inside where your elastic can slot into. But the bootstrap IE actually looks like a bootstrap. So you make a little cut like this and like this, like a triangular and then you allow the elastic to grip onto it. Tell me if I perversity in any way, Robin? That makes it easier cut to do it makes a lot of sense. So which elastic are you using? I think you mentioned four or you haven’t just tell us, which elastics we need to buy. Because and it’s funny with the elastics they’re named after countries, named after animals. So we get really confused with the different brands you see. [Robin]
That’s right, yeah, Ormco does the animals, you can get them on Plak Smacker with different types of animals. Really what you want to look out for a bootstrap, you want to small elastic. Now, the smallest that you can find is 1/8 inch, they’re hard to find the more common small size you can get is 3/8 inch. And, you know, you can get up to quarter inches and things like that for cross arch. But you never want to use a really big one on a bootstraps, you want to use a small one. So you can stretch it out. You can find a 1/8 inch, or they probably do metrics, too in other areas, but we use the inches in in the United States. But you can use a 1/8 and a like a 3.5 or 4.5 ounce. The bootstrap you also want a small elastic you because you’re trying to loop it around to the lingual you don’t want to have rubber band between the plastic and the tooth creating friction. You want it to be as small as possible. So a light elastic, small light elastic is the best way to go. [Jaz]
That’s really good. I didn’t I never really considered that. So that’s a good little pearl there. Thank you. I’m just gonna want to do them. So check them because I’m encouraged any questions coming in. I’ve got a few more questions on myself to ask as well. But if there was any questions about that, do ask away. So I’m just gonna open up the live on here. So no one said any questions just yet. So that’s fine and keep going. So Fine, you’ve covered that. Let’s talk about the button. So when you put the button on the label surface of the lateral incisor, you’re drilling away or cutting away the cervical third area is there a preferred button that you like because I’ve heard actually some dentists what they do is they use an elastic module filling up with flow of composite to make this sort of shape have it in my hands that doesn’t seem to work so well. I actually like to buy the buttons but which buttons do you recommend? [Robin]
Yeah, I like to use the little metal ones even if it’s a lateral incisor I’ll still use the metal buttons I buy them from a website called Plak smackers why because it’s their easy. Reliance orthodontic makes them to you don’t have to have a an account signed up like with Henry Schein ortho, Ormco to buy them you can just buy them online [Jaz]
I didn’t expect you to say that with the metal but there we are. Yeah, you’re coming to find out or using a self cure adhesive or I guess what the method you probably there’s not that much distance you probably could get away with using light cure. Imagine you’re using a self-cured adhesive, right [Robin]
you know I use it to light cured adhesive. It’s composite, you etch and bond and you use a resin composite, just a bracket glue and you’d like your it. [Jaz]
Excellent. So we know which elastic we’re using, we know that it’s about 3.5 ounce or not something not so heavy, because you want you create that friction with a heavier elastic. So that makes sense. Sorry about the lag. Guys. By the way, this is a bit of lag. But we’re still getting to the questions quite nicely. So the next thing to talk about is posterior open bites, which is like one of the most common things we might see for a newbie, it’s happened to me before is I’ve seen it in other people’s cases before we see a person and aligner nation a lot now and again ‘ah guys what I do, I’ve got posterior open bite’, and we sort of touched on it last time where it’s usually an issue with the diagnosis at the beginning. And we can definitely touch on that. I’d like to learn a bit more about that from you. But tell us when we are at that situation. How do you prevent it in terms of diagnosis? When it does happen, is there a place for using box elastics to correct it? Or do we need to go back to your additional aligners and actually do some more IPR in the lower incisors or correct it but you tell me what you think is the best way? [Robin]
There is a best way for each type of posterior openbite but you have to know why you have a posterior open bite. You know the four most common reasons. Number one is you’ve anterior interference, which is usually you try to ensure that lower incisors is a deep bite case, and you’re uncrowding and you end up with anterior interference. And now the back teeth aren’t touching. No box elastics are going to fix that. I’m sorry. It’s just you’re going to be trying to extrude both arches to touch together in the back. It’s not going to work. And you know, I don’t know I said you know that you’d want it to work. If you have a posterior open bite caused by some passive intrusion or some iatrogenic intrusion of the molars. Sure, maybe a little box elastic will work. But you know, what people like to do is cut the elastics [slab their] molars to erupt or settle into occlusion to much better scenario. And you can test for this by checking with bite paper at the end. If you only have anterior contacts from you know, from three to three on the anterior, you’re not going to want to, you know, try to let the molars passively erupt. Now if you have a single tooth interference, you check it by paper, it’s like only on 22-27. Then I’ll go into the clincheck and remove the interference by moving the teeth and then you’ll see the teeth settle back then together with just the rotation of the mandible. So it just depends on the type. So I went through I briefly just touched on the two types of passive intrusion and an anterior interference. The other common cause of a posterior open bite is iatrogenic movement, unwanted movement of the molars. You program in a translation mesiodistal of a molar, you know you’re trying to collect a skeletal class, let’s say class three to try and distalize the molars, but instead of them translating, they’re just tipping back and you end up tipping them out of occlusion. Same thing with buccal lingual translation instead of them translating buccal lingual because there’s no bone there, you did the wrong diagnosis, you ended up tipping them and then you tip them out of occlusion. The only way to fix that is tip them back into occlusion. I don’t think that boxing elastics to get your molar to touch then is the best way to go. Does that make sense? [Jaz]
It does. You’ve certainly covered all those four types. And I love that and they’re really it’s really impossible without knowing exactly which diagnosis it is for your patient to actually figure out exactly which of those four techniques won’t work. But am I right in saying that perhaps the passive intrusion might be more the most common iatrogenic curse types that we see? [Robin]
Yes. And let me I like talking about this. And I’ve talked about this a lot. In the orthodontic community we say we call it passive intrusion. That might not really be what’s going on. And I was thinking for a long time. For the longest time, I wondered what was causing this ever since 2016. When we switched over to the new, more elastomeric plastics away from the older thicker plastics that Invisalign used to have. We saw a lot more posterior open bites, and I was thinking maybe it’s because the molars are pounding on the plastic. Iatrogenically intruding them. But in retrospect, it may not be the case we don’t know if it’s from molars occluding and pushing with the extra quarter millimeter of stretchy plastic is just pushing the molars in and we don’t know if it’s that or we have so many deep bite cases now when we’re trying to intrude the molars we’re actually causing equal and opposite force in the posterior that’s in causes other movements we don’t want you pushing down the front side of the front actually moving the molars are doing something iatrogenically as well we don’t really know what causes this effect. But we do know that a lot of these cases we don’t put bite ramps on them. We were ending up with you know, quarter millimeter of open bite in the posterior really light. So it’s hard to say exactly what causes this but we think we’ve talked a lot about it being from the molars hitting and occluding and pushing the plastic is pushing the teeth in intrusively. Yeah, it’s tough to say oh What exactly causes this but using bite ramps is the prevention. And it’s really common. [Jaz]
Brilliant. So that’s the Golden Nugget that to try and use bite ramps when appropriate to to help to prevent that which makes complete sense. But in that situation I’ve heard my colleagues, some colleagues advocate the following techniques. So just let me know we think about this following technique. So when you have that situation, and you’d like the posteriors to couple a bit better because they’re just slightly pulling the articulating paper to cut the distal of the lower canines of the aligner and give it around about four to five weeks. Is that okay? Or is that risky? [Robin]
I don’t think it’s risky. It really works. It doesn’t take four weeks. If you’ve compressed the ligament space on a molar because of the extra plastic and that mandible, let’s say it’s a dolicofacial profile, they have a steep mandibular plane angle and you’re pounding on plastics on the molars, it will compress the ligament space, you’ll take the aligners off at their appointment for their check. And you’ll see that they have an open by literally cut those aligners probably in four hours, they’re including back, you don’t need four weeks. It happens very, very quickly. Yeah, it’s just allowing the molars to settle all you’ve done is compress the PDL space. And physiologically, when you think about it, if you have, you know, it takes up to nine months for PDL to regenerate if all you’ve done is compress them, it’s just going to take a couple hours for them to settle back in. If that’s the reason why you have a POV. So if you’ve gone for weeks, and I think it’s really important to note if you’ve gone for weeks, you’ve cut the cut the distals of your plastic off and you’ve gone for weeks and they still have a POV. It’s not from passive intrusion. There’s another problem [Jaz]
That’s probably the anterior interference or one of the other things we talked about. Excellent. I’m just gonna go ahead and check any questions James saying hello on the live. Priyanka is asking, when do you use intrerarch elastics to extrusion and what size plastic we use? So you mentioned that already. So just recap the details with size elastic, just for Priyanka. [Robin]
Again, when everyone cross arch, like a five ounce, three quarter or excuse me 3/8 inch elastic, if I’m going from like a lateral or canine trying to extrude a tooth, cross arch. If you’re doing a bootstrap, you want a smaller elastic 1/8 inch. You know, that works too. [Jaz]
Great. Jeff Skinner asked him out why you want to use a lighter elastic. Now I was listening and I’ve learned something that you want to reduce the friction. Am I right in saying that? [Robin]
Yeah, when you bootstrap, you try to get a big elastic on, you can get around the button. But when you go on the lingual, that you ended up getting the big rubber between the plastic and the tooth. And in my mind, it seems like that could be a frictional force that we don’t want to extrude a smaller elastic. It’s not that I want it to be a light force. It’s just that I want a smaller rubber elastic. If I you know you can buy 1/8 inch elastics and four and a half ounce, that’s probably the best way to go. [Jaz]
Brilliant. Jeff, I think the optimal question about where the friction is coming from. [Robin]
And I want to just say that amount of cases that I’m trying to pull down a canine with, you know, elastics, it might be one and 50. And really, if there’s their diagnosis, let’s say we have it blocked out canine number six or 11 is totally blocked out. And it’s way buccal to the arch. First, you’re going to expand or make room through either IPR, extraction, expansion something to make space for it. And then the tooth if the roots in the right position, it’s not going to take a lot of force to bring it down. I would use cross arch, all you have to do is remove the obstacle for that to erupt into position. [Jaz]
Brilliant. Thank you. We’re getting a few more questions now. Which is great. Steven Shark very geeky question. I like it. Stephen is Do you know the name of the paper regarding the inefficiency of interarch elastic? [Robin]
It’s the AJODO journal. I wish I could share it. It’s on the AJODO blog. [Jaz]
I’m going to type it and you say AJODO blog [Robin]
AJODO blog. American Journal of Orthodontics and Dentofacial Orthopedics. [Jaz]
I’m gonna link in there when I actually launched on the main podcast, I’m gonna have it in the show notes. When we can until we’re done. One of us will probably Robin, it will link it on the actual main feed of this as I’m typing it now as well. So we’ll make sure we do that. It’s a good question. It’s good to know actually. So we’ll do that later, Robin. Priyanka has asked another question, which is, do you see more molar passive intrusion on dolicocephalic patients? So these are the long face patients, right? [Robin]
Yeah, you would imagine that would be the case, especially if you’re conceptually thinking that it’s caused by molars pounding on each other, you would think that a steeper plane angle would generate more force than a molar whereas in a flatter parallel to the Frankfort Plane, kind of a flat angle job would create less force on the molars. That’s what you think but no, I haven’t in the hundreds of cases I’ve done last year, I have not found a correlation between dolicofacial and, you know, prognathic profile coincidence between for passive intrusion of molars. [Jaz]
Brilliant. Thanks so much and Priyanka thanks for that question. No, no, no, I see what you mean. But I think that answered the question. So, last few bits Now, just to wrap up one is like a journey question, right? Like your journey. So you’re doing obviously a lot of aligner cases, which is great. And I love the fact that you’re flying the flag for general dentist cuz you’re not a specialist. Have you ever felt that the specialist community has ever looked down on you or given you any sort of hate in any way, because of the level of orthodontics that you’re doing? And you ever felt any friction amongst the specialist and the kind of work that you’re doing that maybe encroaching on that? If you know what I mean, with all respect? [Robin]
Absolutely. This is a tricky question. And really, I mean, all I have tremendous respect for orthodontists and at this point in my career, now I’ve realized how much I don’t know still to this day, I do get a lot of friction. And there’s still a lot that I can’t participate in, even though I want to because I’m not an orthodontist. I’ve always thought it was a cottage industry. And they were just trying to keep me out because they didn’t want the competition. But realistically, the people the genuine people that the good orthodontic got to know, the real reason that they didn’t want general dentists doing a lot of orthodontics, because they understand how complex this is that you cannot treat patients with a clincheck you have to have X rays to understand facial growth, you have to understand a lot going on. There’s genetic issues, you have to take into consideration. There’s skeletal epigenetic issues. I mean, a general dentist takes a weekend course in Invisalign, you can do a lot of harm. So I think that the honest orthodontists were concerned about patients being treated incorrectly and especially growing patients that have a window of opportunity to correct some of these skeletal problems. And they would block me out now then there’s other ones that are just, you know, angry and a little bit bitter for sure. And then I have many instances where I’ve had been kicked out of groups or, you know, I had one guy share my name in my face and in orthodontic groups, because he thought I was doing harm to dentistry in America. And he’s like, doxxing, publicly talking bad about me telling where I live and stuff and you know, but it’s interesting because now where I am, I have the best relationship with orthodontists in Texas, one of my best friends in Austin. He told me that the biggest windfall he’s had to his practices working with me and training general dentists, he has more referrals, I now don’t treat complex cases alone. I work in collaborate, I refer 40% of the patients that come to me seeking orthodontics, not because I don’t know how to treat them, but because I don’t treat them best or efficiently. I have to do hygiene checks, I’m doing comprehensive orthodontics and comprehensive treatment planning. I’m doing restorative plans, veneers, he sends me cases to finish, I get cases started orthognathic surgery cases I don’t you know adult with a skeletal problem, I like to go at the surgical route now. I don’t set them up surgically, the orthodontist do that. Over the years, I’ve realized what is best for me to do what isn’t? I think that a lot of general dentists get in this. And because Invisalign looks like magic. A truly like it’s amazing that plastic can do this. They get in over their heads a little bit, and I can see why some orthodontics get upset, especially when we got smile direct club and companies like that out there. It’s like [Jaz]
I love the community and the fact that you know, you admit that you know, 40% of patients that you might be referring because there are people who are more suited for that type of case than where you are. And I love the fact that you know, you have this great relationship with a local orthodontist. So that’s brilliant. That’s exactly what I want to hear. I think that’s really encouraging. And it’s a shame that you went through what you went through, but I hear about that happening a lot. In fact, next month in the podcast I’ve got like loads of orthodontists are pre recorded with I’m doing a live with you today. They’ve got pre recorded episodes with orthodontists and wonder the core conversations I’m having with orthodontist is when do they think it’s okay for gdps to do treatment, which with some orthodontist will could classify as compromised, which such a dirty word right? But nothing is perfect. And if a patient wants, I don’t know what the scene is in the US. But in the UK, we’ve come to accept that if someone wants to treat the social six, there is a place for that. And I think as long as you’re not doing major harm, and you’re sort of staying within your boundaries, then there is a place for it in Europe. Do you find that there is a place for social six orthodontics in the US just want to just have interest. [Robin]
I there’s tons of cases that I’m only moving canine to canine Absolutely. But this is the really important thing. You still have to have a diagnosis. You can’t just treat patients from a scan or a clincheck. If you don’t know where the bone is, if you don’t know what the face looks like, it’s irresponsible. And that’s I think that’s the big line in the sand is, yeah, I can, if someone has number 8s to stick it out a little bit, it’s protruding. There’s a little bit of crowding that can be corrected with some minor dentoalveolar tipping and realignment, social six ortho is awesome. And there’s many, many, many cases that we treat as social six. I think the most important thing in my practice, especially as I mature, is that I first have a diagnosis of functional health. If I know a patient has good occlusion, their function is good. A questionnaire that in advance and a quick evaluation confirms that their bite is stable and good and they’re not damaging or wearing teeth or causing TMJ problems. Yeah, so six ortho easy and predictable. But if I treat somebody who has got pathology, you know, whether it be a bone pathology, there’s perio, that he’s undiagnosed or a functional pathology, let’s say for example, they have a frictional or constricted bite, and I throw on some aligners and I make it worse by trying to make a very common problem which is a class a super class one we call the class one molar, but the incisors are completely retro reclined, and they’re rubbing down their teeth they have TMJ problems, basically their mandible has continued to grow. And then you try to straighten out and uncrowded the lower incisors. And what you create is more problems, more frictional, more constriction. You know, you can’t get that from a stand. You have to get that from an actual evaluation of your patient. As I say, there’s nothing wrong with a class two or class three skeleton, you know, just because you’re a molar class two, if you’re functionally healthy. Why are we trying to correct that? So an orthodontist, it’s like, oh, you’re doing limited orthodontics was like okay, well, now you started doing distalization of molars or impacting the maxilla or trying to do other things. And now you’ve created a functional problem, you know it sometimes it’s better not to open that can of worms [Jaz]
Very well said and [echo], we want to say, because when I started in Invisalign journey, I realized that I wasn’t as hot in my diagnosis I wanted to be, so then that’s when I embarked on my diploma in orthodontics, so that for that reason that I can really pick and choose my battles a bit like you, I have way more to do to catch up to you my friend, but it to pick and choose my battles, and to learn the art of diagnosis, so that I can provide the best care, most efficient care and the safest care for my patients. And I think that’s it, you know, I think we’re, we’re singing from the same hymn sheet, they’re also just want to say that [Kelly Tyrael] has said that I look up at Red Robin and co are always a big fan. If you can do the work, you’re an expert in my eyes, and we’re all lifelong learners. So that’s a very nice sentiment there. And I think, also Matthew, Sandra says, Well said, Brother, it all comes down to proper diagnosis, which is exactly what you’re echoing so that’s brilliant. So Robin, we’re coming to the end of the podcast, cuz we got the part one that we did take one, I’m gonna marry with this part. So thank you for giving up your time. But can you leave us with two things? The two things I want to leave us with is, what’s your biggest tip that you haven’t already given us? So you’ve talked about the importance of diagnosis, the elastic stuff. So what’s the biggest tip that you haven’t already given us because we’re very greedy. And the second thing I want to know is, how can we follow you more? Tell us about your Instagram, the Tesla, the aligner nation group, some of my listeners who don’t know about the aligner nation group? I’ve been pilot for about two years now. I’m not so much of an active poster. I’m a lurker, but I just love the energy. So please, tell us those two things. [Robin]
I want to say, you know, aligner nation is a community that’s been fantastic. And it’s kind of grown unto itself. We have people sharing cases, we have some of the world’s leading experts. I mean, [sanitising], they’re commenting, we have [Marge Masari], we have you know, Jonathan, because he sees that all contribute some of the best of the best in there. And I’m super thankful. But I’ve been kind of I’ve gotten a little insular lately. I’m back to learning again. I’m taking more courses. I’m doing as many cases that can this pandemic has increased to my caseload and I’m learning from everybody else, as well. So if you want to learn from me, I mean, there’s a lot of platforms that I’m on. I’m always happy to answer any questions dms. And I’ll add a nation so you can follow me there. But the last tip, I think I’ve I don’t want to give and as I become more prolific in speaking, as well as in doing more aligner cases, I’d say that the art of aligners is to subdue the patient’s concerns with as little effort as possible and make it simple. Always start with the teeth that don’t need to move first. What I mean by that is look at a patient smile their face with a full Duchenne exaggerated smile. Look at where the teeth are. Find out are eight and nine in the right place. If they are in the right place. Right click on a clincheck don’t move them. Move the rest of the teeth to those reference teeth. I don’t like to move molars if someone’s functionally healthy. Leave them alone, right click those make them unmovable. And then when it comes to the bicuspids, canines things like this, especially lateral incisors, we know it’s very difficult to extrude a lateral incisor we know that ask yourself does it need to extrude is the gingival [Zenith] where you want it to be in if it is, I would rather trust my you know, composite skills and make it longer than try to pull it down and pull the gums down with it. Get an uneven gingival Zenith profile, especially someone who shows their gums as a high risk, you know, the show a gummy smile. I would rather do some bonding. So make your aligners easy, and don’t try to tackle every case, you submit a case and you get a clincheck back and they’re doing skeletal changes. And you know, you It looks like a miracle just happened. It’s probably not the case you want to take you want to control the variables not move as many teeth. , [Jaz]
Amazing. Robin, thank you so much for giving up your time. Again, I know you’re busy guy. So obviously it’s great to connect with you from across the pond and get this out on the podcast very soon as well so the main listeners can listen to it. But thank you so much for adding to the conversation. Giving you equities on the aligners and sharing those little tips and tricks that we struggle with elastics but you really shocked me in the sense that actually intermaxillaries don’t have as big of a place aligners that I thought they did. And to be fair with you I’m so happy that I could put away my buttons and elastics now so I thank you for that but I’m going to focus more of today’s chat. I’m going to focus even more on nailing the diagnosis and picking the right battles. And also I’m gonna start right clicking more and start not moving teeth more as well as you said at the end so thank you so much Robin for coming today really appreciate my friend. [Robin]
Of course. Thank you so much look forward to doing this again. You’re the best
Jaz’s Outro: Guys thank you so much for listening all the way to the end I hope you found value from Dr. Robin Bethell. He gave some great tips especially at the end when asked him for his top tip like some of those gems he gave were phenomenal and it’s almost like sad to hear his struggles quote unquote struggles and sort of frustrations and how he was almost defamed by an orthodontist. But these are the struggles that a lot of general dentist face. I’m hoping I’ve covered a lot of those themes this month in orthodontic month. I hope you gain a lot of value from orthodontic month. So if you know someone who started starting out orthodontics, and this episode series this month is all helped them, please do share it with them. And as always join the protrusive dental community Facebook page and leave me a review if you thought this was valuable. I’ll catch you in the next episode, guys. Thank you so much for listening all the way to the end.