Simon Littlewood & Padhraig Fleming – Why retention matters

[Music] Welcome to another episode of the European Orthodontic podcast, where we look into the latest innovations, evidence-based practices, and stories from leading orthodontists across the world. I'm Finn Gagan, I'm a council member of the EOS, I'm an orthodontist from Dublin, and I'm currently the president of the society, and in June of this year we'll be hosting the European Orthodontic Society Congress for the first time in Dublin, and we would look forward to as many of our listeners been able to attend. We think it's going to be a great occasion. This podcast is brought to you by the EOS, which is committed to advancing orthodontics through science, collaboration, and education. So today, we'll be talking about retention, with Professor Paul Rik Fleming from Dublin, who is the scientific chair of the meeting in June, and Professor Simon Littlewood. So hello and welcome to you both. Hi Finn. Hi. I'm going to introduce Simon Paul Rik we've met before in a previous podcast. Simon is the consultant orthodontist at Bradford Teaching Hospitals, an honorary senior lecturer at the University of Leeds. He's internationally recognised for his research on orthodontic retention, long-term stability and evidence-based clinical protocols with over 50 peer-reviewed publications and numerous international lectures to his name. He is also a co-author of an introduction to orthodontics. Simon, thanks for agreeing to this, and it's a real pleasure to have you do this podcast with us today. Finn, thank you and great to be here talking about the most important topic in orthodontics, orthodontic retention, of course. Paul Rik, thanks very much for agreeing to do this. Thank you, Finn. Delicis be here as well, and also Delicis be talking about retention. Great. So I'm going to sort of introduce it from where I sit and practice quite often, which is I do agree it is one of the most important things in orthodontics, and it often gets overlooked. It is difficult sometimes because I feel that perhaps an orthodontist thinks retention is one thing, a dentist thinks it's another, and patients think it's something completely different. And then we have to look at what is orthodontic retention and what are age-related changes. So just to paraphrase, often with our patients, and I think it's the same in the UK, we'll see our patients after treatment for a defined observed period of orthodontics after which we will discharge them, we'll send a letter to the referring dentist and ask if they will keep an eye on things, and if there's a problem to let us know. And our patients sort of where our retainers or have retainers on their teeth, and we don't really structure that much beyond that. Would that be fair to say? Yeah, I know. I think that's that's true, Finn. I think it's a really important point, I suppose, in terms of maybe understanding what realistic expectations should look like. I tend to think that we're mitigating in a sense against relapse is the term that we use, but in reality, we know the teeth move throughout life. This is the challenge that we've got. I'm sure you've heard that unfortunate phrase around stability effectively being post-mortem, you know, the teeth only stop moving after we die, sadly. And that creates massive challenges. And I think it's important to be able to maybe disentangle in one sense, even so patients understand it better, genuine relapse from that maturation or change. And what I tend to think, you know, based on research, is that really, I think the first two years after our treatment is genuinely when relapse might actually occur. Beyond that time-pointed, probably is more maturation or change that's occurring. And I think in a sense, you know, the way that we supervise patients over the first up to two years after treatment, I think that hopefully deals with that risk period for genuine relapse and might, might occur after, hopefully, are much more subtle changes that really do relate to that maturation or change aspect. Yeah, I agree with that. We're talking about two separate things here, aren't we? We're talking about relapse of our orthodontic treatment. That's a teeth return to where the originally came from. And then we were talking about unwanted post-treatment changes that would happen whether the patient had treatment or not. This is a normal age phenomenon. And I think it's important our patients know that. I think if they think it's only the first that the way we tend to just for our orthodontic retention, that's a challenge to them. But if we can explain to them actually what we're trying to do here is resist normal age changes. I think patients can get that because their head is a bit better. It's a bit like a lifestyle choice, I think. We talk about four pillars of health, a good diet, good exercise, good sleep, good mental health. And we know that we have to maintain those all the way through our life to maintain a healthy lifestyle. And if one of those drops out for a prolonged period, then we're going to get problems. And on that four pillars for orthodontic patients, you might want to add a fifth pillar of retention. That if they want to keep their teeth in a reasonably straight position, they need to commit to retainers long term. And if they drop a tour without, then they're going to see some relapse. And of course some patients will decide, well, I can't be bothered with retainers, I don't want to do that. But actually most will want to do it if we can just give them that information. And once they understand this is more their commitment to anti-aging, I think we're more likely to get their engagement with it long term. In terms of information and communicating to a patient, and how should we restructure that when we're at the very beginning. Like I know in practice, I'll talk an awful lot about what we are going to do and why. And then we talk about the options of how we're going to treat the patient. And then we're going to explain the estimated duration. And then we talk about the retention phase. And currently we're sort of saying, well, you need to retain as long as you want your teeth to stay straight. How would you see how you can divide relapse from age-relative change? How would you introduce that straight up or how do you do that with your own patients before, during and after treatment? Okay, well, I can talk for our clinic in Bradford. We have posters up about retention in the weight in them. So that's the first in this age. Retention tends to be the last thing somebody hears. And by then that kind of exhausted, they've heard all stuff about the braces, the extractions, and they're no longer listened to you by the time you got to the retainers. And yet the retainers is probably the most important part. So we have posters up about retainers in our way to them. We have pictures of the staff with a picture retainer, and then a little phrase about what retainers are and what they're from. So even before they've even met us, they've seen something about retention. And then we talk about it right from the beginning. Of course, apart the treatment plan. I think how we used to do it was we used to mention it on the original consent form. Then the patients, and we would forget about it for the next year and a half, two years. We come to debon day. The patients just so excited about having the braces off. We mention retainers, and they're not really listening because they're just so pleased to get these horrible braces off. And they want to smile at people. So all the way through treatment, I'm talking about your retainers all the time and just mentioning it to them. Just dropping it in. So you're doing really well here. Just following our instruction, you're wearing the aesthetics. But remember, all this is going to be a waste of time, unless you wear your retainers long term. So we've got to see these patients for a year and a half, two years. It's a perfect time to drip feed this information in term. So by the time it comes to debon days, absolutely embedded in the patient's mind about the need to commit to retainers long term and what that means for them. And they can then choose whether to follow that advice or not. I think the traditional way of just dropping in and right at the end of treatment probably gets lost in the excitement of the debon. Yeah, no, I think you're absolutely right, Simon. I think from my perspective, I think at the the initial visit, the earliest part of the consent process, it's essential that we do highlight the importance of retention, ISO pictures and physically models, for example, of fixed retainers. It's interesting, what a high proportion of patients actually kind of bulk at the picture and the suggestion that a fixed retainer will be there lifelong. So I think again, it's important that it is raised at the outset. I tend to present it quite simply in that from our own data, 30% of fixed retainers over a three year period are likely to fail or to require some form of adjustment. So they've hopefully got a sense of the commitment that might be involved both in terms of fixing and removing retainers. The other thing though that I would say is that it's important that we are, I suppose, you know, friends and granular around what retainers are actually doing. And in reality, if we think about a fixed retainer, what is it doing? Well, in my view, it is maintaining the alignment of one, two, the relative to its neighbor. It's not doing any more or less than that. And if we think about a patient, for example, with a very large overjet that we're correcting and really the. retainers in the long term have very little to do with the prevention of relapse, and because we know class two corrections, one of the more stable things that we do. So there are certain features of malocclusion that are much more susceptible to change, things like reopening of spacing as we know a correction of individual contact point displacements, while other features might be less dependent on the wear of retainers. So again, I think important just that we are, as I said, fairly kind of granular about that, and again, that does form part of that initial conversation around how to treat a patient and equally ultimately how to retain as well. So we see a wide range of patients, so we have, but we can roughly break the patients into growing and non-growing patients. How does growth status or even within a growing patient their age influence your decision in how you would approach retention? Really good question. I think I suppose in terms of fixed retainers, I mean Simon will know this as well, I'm a big advocate of fixed retention, I had a very, very steep learning curve around use of fixed retainers. I've always felt the necessity in certain scenarios, but certainly as a postgraduate student and maybe less experienced clinician, my failure rate with fixed retainers was very, very high. So I had to work on techniques and develop predictable means of placing them, but I tend to use a lot of fixed retention in both adults and adolescents. I get a little bit more concerned about fixed retainers in adolescents, particularly upper fixed retainers. So I'm a little bit more conservative around how far back they go so they would generally involve just upper lateral and size or to lateral and size, for example. In terms of where of removal retainers, because I use a lot of fixed retention, actually I feel less reliant on where of the removal retainers. But I actually think, Finn, we don't like talking about this very much, but based on the healthcare system within which we are treating patients, there is a difference in terms of compliance levels with removal retention. So for me, that's almost a bigger factor. And we know again from some of our own work that Dalian McGrubby left, you know, two years just after completion of orthodontic treatment, only one in three of our adolescent patients were continuing to wear the removal retainers. That again was in a patient cohort who were not paying for their treatment. But I think the healthcare system is also the context is important as well as the age of the patient. Yeah, I agree with that about the removal retainers. And the most important research that's been done was that research you're talking about with Dalian about the fact that in the first year or so, most retainers seem to work well, but when you follow them up three or four years later, there's a huge drop off with the removal retainer patients and therefore more relapse in there. Interesting the ones that wore the removal retainers, the retention is fine. So I think there's something in here about our skills to motivate patients to wear removal retainers. I think we kind of think of ourselves and we are as dentists more surgeon than physician. And what I mean by that is we're used to seeing a problem, doing some sort of procedure, curing it and sending the patient away. And we like to do that as dentists. We like to do something, send them away with as little input from the patient as possible. In healthcare, it's not like that, of course. So the patient who has maybe cardiac disease, they have a problem to maintain health after the treatment, they would need to maintain good health, maybe good exercise, good diet or whatever. So the best clinicians are the ones that can motivate those patients to further advice about the diet and the exercise and the good lifestyle. I think it's the same with orthodontists. The skill to motivate patients and help them understand the need to wear retainers long term. I used to kind of blame the patients if they didn't wear their retainers long term. But maybe I've changed that a little bit now and think, well, maybe it was me not motivating this patient enough, not educating them enough, not making it clear enough. How important is to wear those retainers? And maybe I've not done my job properly to try and get that information over to motivate the patients to wear and commit to the retainers long term. Thanks guys. I'm sort of interested in how we manage post treatment because as I mentioned before, we tend to see our patients for a year, some people see them for a longer, but I'm in a practice that has had two or three generations of orthodontic patients. So in certain cases, I see the grandchildren of people who are treated in the practice I'm in. And you sort of start thinking more and more about what constitutes successful orthodontic treatment and the idea of retention when the benefits of orthodontics come into place based on how stable or how long we are able to maintain the result we've obtained throughout treatment. And a question that comes more and more to mind is how do we manage that? How do we, after a year, we discharge, we say, very well done. Now, what happens next? What is it? So just to illustrate this, generally we assume the patient will see the dentist and then we will assume that the dentist will be aware that the patient has had orthodontic treatment and will assume that the patient will remember to bring their retainers to the dentist and we assume that the dentist will ask the patients to see the patient's retainers, etc, etc. What does your opinion on that differ from mine? And the second part of the question is what should or could we do differently if we think there is a better way of managing long-term retention? Yes, a really good point, Phil, and you assumed a lot of things there about the dentist doing things there. I think there's kind of two ways here that the reality is that the patient isn't going to come back to the orthodontist in most cases on a long term basis. Certainly within the UK system, the national health system, we can follow patients up for a year and then they discharge. So then what happens after that? Well, ideally, if they're going for regular dental checkups, as part of that dental checkup, we would like the dentist to check retainers. I don't think it routinely happens and there's things we have to do with that. I think there's two sides to that. One is to maybe educate our young dentists, our undergraduates about one of their important roles of checkups is to check retention. Now that we're happy for them to check for careies, if they're perio or maybe look at a bridge or an implant that's been placed, why not a 10 second check of the retainer at the same time? Now, it may well be that they don't feel they have the skills to do something about it if they see a problem and then the message would be, well, then please refer back to Finn or whoever to deal with the retainer problem. But the dentists have got a really important role, the thing to have that quick and it literally is a 10 second check. And if they're worried about anything, send it back. And maybe we should also be saying to the patients, when you go to your dentist, take your retainers a lot and when certainly when we discharge, we like to dentists and say, we would like you to do this just a 10 second check to see if there's any problems there. The other way is an additional thing is maybe have some sort of remote monitoring. So we're entering an area in healthcare where all of us will be dealing with healthcare and interacting in a different way. Traditionally, what happens at the moment, we notice the problem. When our health is the patient who died and knows it picks up the symptoms and goes to the doctor and then the doctor will decide whether you go into specialist care. In the future, I think it will be remotely monitored whether it's our heart, our blood pressure, our blood count, whatever it is. And then if there's a problem, it flags up and it triggers the patient to go and see the clinician. And I think it could be the same with orthodontics. We know the Somerdi technology with things like dental monitoring that can scan the tea with the patient's own smartphone at home. And if a problem is noted, that could trigger a visit to the orthodontist. That technology is really new at the moment. It's exciting technology. I can feel like we are additions and maybe even the company don't know how to use that yet. But that idea of remote monitoring at home, I think will become something for the future, not just for health, but also for dentition as well. And then those sort of situations, maybe it will be easier to keep a check on patients post treatment changes. Yeah, I think that's absolutely true, guys. I think in terms of the role of the GDP and remote monitoring, I think really, really pivotal. I think the only other thing I would add, as I suppose, is what we have done as well during our period of treatment and retention. It does potentially have a bearing, obviously, on the long term success too. And we can't maybe lose sight of that. Both in terms of, well, our provision of fixed and/or removal retainers. If I did, would maybe removal retainers, first of all, Manivus these days do tend to gravitate towards, you know, term of foreign-dressics type retainers. There are vast differences between these materials. I think Manivus really genuinely don't know what type of plastic we're using. When we deliver an estic type retainer to a patient, there are huge differences in terms of physical properties between them in terms of longevity as well. So I think it's within our control to understand that and to hopefully, you know, to provide devices that are likely to last reasonably well. And there was, for example, I think it would be very. interesting retrospective study from New Zealand a few years ago, which estimated mean survival of Essex type retainers for as little as four months. Now, obviously, for Essex retainers, we're being lost or we're being worn through over such a short period on average, we would have big issues. So, again, there are things that we ought to educate ourselves on in that respect. And I suppose the other aspect then is fixture tainers. And I suppose there are two major issues with fixture tainers that are purely within our gift, which is whether they will fail. And often, as we know, failure happens airily. But equally, whether they become active, and I think again, we're increasingly aware of wire syndrome or activation of fixture tainers. Yeah, well, I suppose it's activation of a wire which should be passive. So, as we know, retainers should be a passive device. And for whatever reason, it becomes active. So, it begins to, I suppose, develop a tooth moving capacity. Again, people, I think, without necessarily detailed knowledge of the topic would begin to point to the finger of blame at us or the dentists, maybe reflexly. I'm not sure that that is the case, to be honest. I think these can develop, we feel more likely if there is obviously active placement. There has been some research, which is shown, for example, that indirect placement of fixture tainers is less likely to result in inactivation of the wire. However, my own view is that fixture tainers can become active during function. So, it's more likely to happen, for example, on upper fixture tainers, which we know are exposed to occlusal forces in particular. We must get on hard foods substances, you know, fixture tainers are in a relatively hostile environment for many, many years. They can become deformed subtly without debonding. And ultimately, therefore, forces can propagate quite often towards the terminal teeth on the arch wire causing these kind of fairly dramatic twisting effects and torque changes, which, as we know, can potentially have predominantly compromised the teeth. I think increasingly, whatever research there is on these would point at least a question mark over the use of round at multi-stranded stainless steel wires. I think it is much more likely for this deformation to arise with these, than, for example, with rectangular wires or similar than with chain-like retainers. So, I think, again, while further workers required, I think, increasing, we were beginning to appreciate that these round flex for wire retainers are potentially problematic. And I think it wishes interesting, isn't it? Because that's probably the most popular, or traditionally the most popular type, a twist-flex round wire. I think we'll see that gradually disappear, and we're moving to different types of materials there. Well, we think probably of wire syndrome that unwanted tooth movement happens in about 2% of boundary-tainers. So, for those of us who do a lot of boundary-tainers, we are going to see that occasionally. And so, these patients do need to be checked long-term, just to make sure we don't see these subtle changes. You mentioned Simon earlier about remote monitoring and other forms of technology. What about, from a material's perspective, what's coming about that may help things with that aforementioned problem, help with, you know, there are any indications that there are new materials, or new placement methods that may help with some of these failure rates, or with some of the unwanted sequelae that you mentioned of fixed retention. Yeah, we certainly hope so. This move from analog to digital has generated all sorts of different materials that we've not used before. So, now we can 3D print wires, and there's been very types of tri from nickel-titanium to titanium. And the idea of the CAD-CAM produced retainers, like all CAD-CAM stuff is maybe slightly more precise, so it'll fit more exactly, maybe it's easier to clean, maybe it's more comfortable for the patient, maybe it's less active light and become active. I think at the moment, it's fair to say that most of the research that you've shown shows that these CAD-CAM wires are very efficient, a nice addition to our workflow, certainly helpful from a clinician point of view. But I don't think we've been able to show as yet a real advantage to the patients. It's like a lot of digital transformation, it's really helping the workflow of the practice, but not necessarily radically changing the outcomes of the patients. I would hope that we are going to see some improvements there. So, these, the new ones are no worse, and we would like to see some new materials that will perhaps behave a little bit more predictably than our traditional bond retainers. Yeah, I agree with that time as well. I think, Fin, you know this, but we're doing a little bit of work involving CAD-CAM type and fixed retainers as well. And I suppose it's, we've all heard the phrase, there's nothing new in orthodontics. Of course, there is a lot of new things in orthodontics, but I'm going back, maybe to a tradition design, one thing we've been testing, I was a fixed retainer wire, which your Glocking Geeser in Austria has pioneered involving three and three designs, whereby the wire is bonded to lower canines only, but because the goodness of fish associated with the CAD-CAM design, we can scale up it into approximately, it might therefore minimize the risk of unwanted irregularity while improving flexibility. So, we've been looking at that, for example, but I'd agree with Simon, a lot of the CAD-CAM designs look beautiful. They help our workflows, but to this point, I suppose it has me as I suppose, you know, proven pivotal in terms of changing outcomes at least in the long term. I think, also, however, I think, again, going back to removal retainer materials, I think advances in plastics, I think are helpful. And we always have the problem, as I was with retention, whereby, you know, we can't use removal retainers that are too rigid because of obviously potential issues with fish, but we know, for example, polyurethane type materials are likely tougher, likely have better longevity while having obviously good aesthetics. So, again, in terms of kind of long longevity of these retainers, again, that can only be beneficial. And I suppose, minimize the risk that they will require replacement, because often the problems come when retainers are lost, or when patients maybe need to see us to replace a broken retainer, but struggle to get in for that appointment. So, at least if they have a retainer, which is less likely to cause an issue, you know, hopefully we can safeguard that retention, maybe slightly better. Yeah, while we're talking about 3D printing, we mentioned a little bit about bonder retainers there, but of course, we're in the era where we're trying to desperately try to produce 3D printed aligners, and therefore clear plastic retainers as well. It's a difficult area, it clearly is difficult, because all the bigger line of companies would much prefer to produce direct printed plastic rather than all the models first, and then suck their new plastic over the top. So, clearly it's something that's technically difficult to do, and we know there's new products coming out, very fresh, the market in the moment. One of the big advantages, you potentially, for 3D printed and clear plastic retainers, is we can control the thickness of the plastic in different areas over the occlusion. The way we make clear plastic retainers tradition is we suck it down onto a cast, which thinns the plastic in differential areas. So, a bit where the plastic is thin, it's over the low end size, because that's where the suction force is bigger, and you get really thin plastic over the low end sizes, which is often where they begin to crack and break. If we 3D printed, we can control the thickness of the plastic in different areas, and toughen it up in the areas where we think it's going to be more light to break. So, it's kind of exciting technology, I hope that if we speak in five years time fingers, I'm sure your podcasts will still be going in five years time. We'll be talking about 3D printed plastic aligners and retainers. Could I make a little segue? Because we've talked for the last few minutes a little bit about materials and the type of retention. And I just want to use an example from my own experience over the last few years of seeing more patients who would prefer to be treated with clearer aligners, and having to learn how to treat people with a removable appliance for a long period of time. And one of the things which has been a big learning curve for me is the very idea of asking someone to wear something on their teeth for a long period of time requires a certain approach, a certain psychological stage in the patients' developments that they understand why they're doing this. But also the opportunity during treatment to pick people up when you see their flagging either in clinic when they come in to have their treatment evaluated or via remote monitoring when you see things are starting to lag a little bit. As a two-parter, I'm sort of intrigued as to yes it's very important the material side of things is improves and is addressed, but it's the kind of idea of how do we sort of create a vision for a patient, for their teeth to say, well, if you want this to happen, this is what will need to be the case for you. And do we say forever and ever or until I retire? So, for example, the question I was going to say is, so my sonar daughter coming into me, or your sonar daughter, and we're not talking about costs or healthcare system, are we going to go belt and braces, which is fixed, upper and lower, six to six, upper and lower, hallies alternating with vacuum forms every other night, and you're going to see me every three months or you're never getting any pocket money ever again. What would you do, or what do you see the most pragmatic way to achieve a long, to maintain long term and to sort of mitigate patients' expectations to say, well, they're probably not going to look like these in ten years time. They're going to look something like this, even with the best will in the world. But in order to get them to look like this, this is what we're going to need you to do. And the role of the dentist or the orthodontist in that, would you have, is that too much of an ask to sort of say what you think would be ideal for your average patient if you could create a system to manage that? OK, if I can take that question, Finn, I think it's a shared decision-making process here. I think it's different for different patients. So I think there's some patients who are absolutely obsessed with total alignment, and we know these patients are ones that can spot a slip contact from twenty yards away. And those sort of patients absolutely need the advice about all the belts and braces approach to retention that you were talking about there. But if the other patients will say, look, I can't keep a boundary tailer clean. I haven't been very good during treatment. I'm not going to see my dentist ready to have it checked. And those sort of patients, I'd be talking about the importance of removals. Other people say, look, honestly, I'm not going to wear a removal appliance long term, what can you offer me? And then we'll talk about boundary retainers. And in the end, this is a choice for the patient. What we can do is to educate the patient. Give the impression that everything's going to be fine without telling them what the commitment will be. I think in reality, there'll be lots and lots of patients who'll give up on the retainers long term, but at least that's their decision to do it. So I think we tailor the retention regime to the patient in front of us and involve those patients in the conversation. And like with most healthcare, if a patient's involved in the discussion, they're more likely to comply and follow what's going on. Great. Thanks, Simon. That was a nice answer to my very long-winded question. Paul, what would be your version or what would be your take on that question? Yeah. No, I think similar, really. I mean, I think you do have these patients, for example, you just do bulk at the prospect of wearing fixed retainers. Unfortunately, as we know, we just don't comply with the removal of retention. I think we quoted some figures earlier, for example, two years into a research project we found just one in three patients still wearing the rest of the type of retainers. And obviously, if they're not wearing the retainers, maturation will change. I think at that point is going to take hold. So we're likely to see slip contact points lower anteriors and ultimately upper anteriors as well. I mean, I tend to suggest, you know, I do use a lot of fixed retention. I think one advantage of that is that the burden on wearing removed retainers is reduced. Therefore, associated wear is limited. They're likely to last for longer, for example. And I think that in itself is beneficial. I tend to move patients on to because I'm prescribing fixed retainers almost uniformly on to night, only wear of removed retainers from the outset. I tape where the wear is down quite early. So within 12 months or so, they're wearing the removed retainers one to two nights a week. So that's kind of the approach that I tend to take. But, you know, I think in doing that, I think in a sense, I'm being realistic about what I feel, you know, the likely compliance will be long term. But at the same time, you know, if we don't, you know, wear removed retainers and fixed retainers are not in position, maturation or change in effect is just likely to take hold. But if we get them through the first, you know, year to two years, hopefully we will have managed that kind of high risk period for genuine orthodontic relapse. So I mean, you made a point there, you were illustrating a patient and the one who wouldn't tolerate minor changes. And those are that patient, that type of patient need a bit of a talk into long term to say, listen, you know, with the bestwill in the world, this is a biological mechanism. You are growing, you are changing. The likelihood of being able to maintain this result for the rest of your life is nil. Well, a short answer to that is yes. I think trying to get the patient to be realistic about age changes. Sometimes the example we might give is that the patient comes in for a facelift from the plastic surgeon, we'll have it done. That patient wouldn't then expect that face to last forever and without some sort of interception from the plastic surgeon again in maybe five to ten years time, we start to see some deterioration. And I think modifying our patient's expectations is key for all orthodontics, of course, isn't it? Because the happy patient is the only happy, not because the brilliant occlusion we've given at the end, but have we reached their expectations. So we have to make sure they have realistic expectations. And your point is a good one about retainers that we cannot freeze it at this point. The phrase often used with retainers is we reduce the risk of unwanted change on term. And if I say it stops it, it reduces the risk of it. And hopefully the patient's realized and will therefore accept some small changes long term. One question in terms of technology and future strategies, can we develop a sort of a profile for each patient based on their presenting malocclusion? What I mean is open-bite, generalized spacing, diastomer, large rotations. Can we essentially at the start of treatment look at five or six aspects of a malocclusion, input them into our algorithm and there'll be an answer fixed or non-fixed, every night versus where do we put the individual malocclusion in today's world and maybe going forward in the future into how we retain? Yeah, I think that's a very good question, Finn. I suppose it's probably something I have an interest in. We developed, I suppose, a hierarchy of stability really in terms of orthodontic treatment. I suppose based in one sense on the corresponding hierarchy around ortho-nathic surgery, but obviously quite different in that we do provide retainers to prevent post-treatment change after orthodontic antibiotics. I suppose within that what we highlighted was, first of all, I suppose the idea that really we should probably be talking in terms of I feel of retainability rather than stability, following orthodontic treatment because so much of what we do does require retention. Within that, what we were able to highlight as suppose looking at the research is that there are certain features that I hesitate ever to use the word "stable" but that are more likely to be stable. Within that category we would put "antiraposiria change" so correction or reduction of an overjet and actually correction of a class 3 and size of a relationship in a patient 2 is non-growing. Those patients I would feel actually are not really benefiting from our retention regime. Those teeth are unlikely to change and notwithstanding the use of retainers. On the other hand, you move down at the other end of the spectrum towards anti-eropen by correction. We know not alone is that very, very unstable and as in the teeth we'll obviously want to relapse but equally it is incredibly difficult mechanically to actually deal with or to retain that correction. And that's where again we talk about retainability rather than necessarily stability because if we think about it the removal of retainers that we use are not particularly good in isolation at maintaining for example extrusion of mixitory insiders or even intrusion of post-serior molars. And so it may be that for example to retain those kind of complex changes perhaps we might need to modify our standard retainers look at using active forms of retention for example. So I think looking at it in that way may be hopefully helps us to I think it turns the patient communication to give them a sense as to what we as orthodontists might to a small degree at least have some control over maintaining the correction of but equally what they will require significant long-term commitment to actually maintain as well. Super. Thanks, Paul. So Simon you've agreed to come and speak as a keynote speaker in the US and June. Yeah. excellent and delighted to be coming to that. I think it's going to be a very popular conference, actually. Everyone wants to come to Dublin, it's so easy to get to. So I think you're going to be absolutely packed out. So yeah, I'll be talking about digital technology and authentic retention, building on some of the stuff we've talked about today, hopefully. Hopefully you see and lots of the listeners there next June. Thank you very much Simon. I really appreciate that and I'm and Paul, thanks a million for both of you giving a good overview and it's I think it is a really important and the longer I'm working and the more patients I see and the more generations of patients that come through the practice, you really realize how important the retention part of orthodontics is in the overall success of what we do. And before we sign off, I just wanted to give a quick reminder to our listeners. Please be sure to subscribe to the podcast, the EOS podcast, which is the European orthodontic podcast on Spotify to receive a do notification when a new episode is available. And while you're at it, could you look and explore the brand new EOS resource library, which is a growing collection of webinars, Congress recordings, abstracts and more, created to support all of our EOS members at every stage of their careers. You could find that online at www.eosEurope.org. Finally, mark your calendars. Seventh to the 11th of June, 2026, Dublin or Ireland will be the 101st Annual Congress of the European orthodontic society. And we will bring together over 2,000 orthodontists, including Simon and Paul Ric from all over the world with an outstanding program on the theme, innovation, meets clinical excellence. We can't wait to see you there. This podcast was brought to you by the European orthodontic society and is sponsored by DWLingle Systems, Improving Orthodontics. Visit www.linguelsystems.co.uk for further information. The EOS is a membership organization with over 3,000 members from all branches of the orthodontic profession, working in private practice, hospitals and universities throughout Europe. To find out more, visit www.eosEurope.org and follow the EOS on Instagram, LinkedIn, Facebook and X. All views expressed on this podcast are solely those of the host and guest speakers and do not reflect the opinions and beliefs of the European orthodontic society. Sponsors have no input into the selection of speakers and topics.