Michigan Splints AKA Stabilization Splints are the ‘gold standard’ occlusal splint according to many occlusal camps.
Dental School told me that this Splint is the only one I will need to know and it will cure all. If this does not work…maybe the patient has ‘atypical facial pain’ 😉
Now before you all attack me…. I have to confess. It is actually a great all-rounder splint – but there are some key reasons why Michigan appliances (or Tanner for the lower) is massively overrated!
Listen to this episode as I cover:
- What is a Michigan splint?
- How does this splint work?
- What records do you need for a Michigan splint?
- Do you need a Facebow?
- What are the limitations of Michigan occlusal splints?
- Why might other splints be better for many scenarios?
- Why you should be careful prescribing Michigan splints to primary clenchers
Protrusive Dental Pearls were sent in by fellow listeners regarding patient care and rubber dam hole spacing.
Have you checked out the rest of the episodes from Splintember?
Here is a rough transcript:
Lets face it – Dental school barely scratched the surface in a lot of areas, including Occlusion and splints – so it should come as no surprise to you that Michigans splints are not as great as you were taught they were.
Michigan splints are actually a really good all rounder splint for all the main diagnoses within ‘TMD’ – quite often when I find a tricky case and I am unsure if the issue is more muscle or joint, I will recommend a Michigan – but still, it is a massively overrated appliance and is totally overkill for most of our patients.
Lets start the basics – what is a Michigan splint? It is classically a hard upper splint.
The lower is called a Tanner.
Aka Stabilisation splint.
It’s a centric relation appliance. What does this mean? I explain in the podcast (so listen up!).
I go in to this appliance in a lot more detail and all the shortcomings.
Fellow geeks, to conclude:
It’s a great all rounders splint. And if ever you’re unsure of joint vs muscle diagnosis and you can convince your patient to spend hours in the chair, spend that money and you think they’ll comply, then go for it.
It’s a great splint. But if you’re more concerned that your diagnosis is muscular, or the asymptomatic patient, and perhaps as an appliance to deprogram your patient….there are definitely more efficient ways to deprogram your patient.
And that’s exactly what we’ll talk about at the next episode….stay tuned for the rest of Splintember!
Click here for Full Episode Transcription:Opening Snippet:Dental school scratched the surface in so many different areas including occlusion and splints so it should come as no surprise to you that the grand michigan splint that they taught you is the best ever may not be as great as you were taught...
Jaz’s Introduction: Hello fellow dental geeks and welcome to episode 40 of the Protrusive Dental Podcast, now this is the third one of Splintember and it’s gonna totally upset so many dentists. Gonna make you guys some of you very angry, very hurt, very upset and I make no apologies for it. You know this needs to be out there and let’s try and keep an open mind and learn and maybe I’ll learn something from you guys as well from the backlash but really I’ve done my homework now and I’ve come to a conclusion that Michigan splints are overrated but before we go there I’m going to share with you two Protrusive Dental pearls, two brand new ones and these were sent to me by the Protrusive Dental Community. Thanks so much, guys for listening and i want to put your stuff out there as well.
So the first one is from my buddy Sim Singh, he’s from London and his Instagram handle is @drsimba. Now, Sim is a young dentist and what he’s told me is that now that there’s so much time available because of fallow time and covert 19 restrictions and whatnot. He’s finding it so useful to call his patients after a tricky procedure or after extraction and just ask how they are you know and give them some advice and follow-up advice and telling them that you know it’s any issues I’m always here for you and he’s found a massive value from this and too fair it reminds me of my first year after dental school and I learned that lesson then as well and such a great one if you can and if you have the time call your patients and it adds such a massive personal touch and they will never ever forget and they’ll love it. So that’s a great little pearl from Dr. Sim Manga.
The next one is from my buddy Jake Garner in Derbyshire, his Instagram handle is @jakegarnerdentistry. Jake is a really good dentist. He’s good at adhesive dentistry.
Check out his Instagram profile and his rubber dam tip is that when you’re trying to get the perfectly spaced holes He found it very useful that if you have a study model of the patient that you’re about to apply rubber dam on that. You get a pen or a marker and you actually put the rubber dam over the study model and you sort of mark the middle of each tooth and then you punch your holes like that is extreme accuracy that you get from doing it that way and it’s a great way to do it the other way to do actually is you can do it in the mouth like you can actually put the rubber dam on the teeth and then get your pen and mark the teeth with the pen while the rubber dams just sort of I guess wrapped over the teeth and then that gets you perfectly spaced holes which allows you to get a better seal, better inversion less of the papilla sort of showing through sometimes So these are two Protrusive Dental Pearls shared for you by the community. So thanks so much guys for sending those in and if you remember in episode 39, the last episode where I talked about a little bit about TMD and why it’s not such a great thing to get into perhaps or a great term for that matter.
I want to give a shout-out to Dr. Anish Dhunna. Now, Anish is someone who also i’ve got to know through the podcast. I love his drive and his passion for dentistry as well it’s great to connect with like-minded dentists all over the world. Now, Anish also mentioned about adaptive capacity which very much goes hand in hand with the weakest link theory i talked about in the last episode. So adaptive capacity is another way to explain why some patients end up getting symptoms and others don’t. So for some people all the insults and the trauma that the temporomandibular joint and the teeth and the PDL have. If it’s below their adaptive capacity they will unlikely they are unlikely to get symptoms and problems however, if the threshold is low or their adaptive capacity is low if you like then they’re the ones who are more likely to get symptoms and problems and that’s a great sort of theory. It’s only a theory and the first time I heard this theory was from Dr. Chris Orr about seven years ago and I just think it’s a great way to look at things well. So a great term adaptive capacity, thank you. Anish for sending that one in.
Main Podcast: So Michigan splints, right? You think this is like the best splint ever. That’s what dental school taught us, that’s what the restorative department said is the gold standard and to be absolutely fair it’s actually a pretty good splint, okay? So I know the title I have is quite provocative and anti-Michigan but really if I’m going to be straight up with you, I’m going to say it’s a really good all-around splint I just think it’s overrated. There are some diagnoses which you might make for example myofascial or if you want to deprogram someone I’ll get into all this a bit deeper and deeper as the episode progresses but really there are better splints for certain functions than a Michigan but Michigan is a great all-round splint and I’m not going to poo-poo it just yet because there are some good points about it. I used to use Michigan appliances a lot like loads right and then for the reasons that I’ll go into a bit later in the episode. I haven’t stopped using them at all. I tend to use Michigan appliances when perhaps they’ve worn one already and they’ve worn through it and they were able to have good compliance with it and good results with it and I’ll remake them a Michigan splint or a tanner appliance. I tend to use Michigans nowadays for cases where I’m not 100% sure of the diagnosis. It’s a bit tricky there are some joint-related issues and some muscle-related issues and perhaps the joint may not be able to accept a load and we’ll go and go you know
I’ll go into that bit more and if i find that it’s more of a slightly more of a joint-related issue than a muscle-related issue, speaking globally then i might be tempted to give a Michigan appliance in that case.
So let’s just start with the basics what is a Michigan splint? It’s an upper hard appliance A lower one is called a tanner appliance it was invented or designed in the university of Michigan, they were sort of doing some experiments on the different types of hard appliances and what kind of designs would come out on top and they found that the Michigan splint as the design they came up with would be the best and I’m going to tell you what that design is basically and a lot of you already know this you know I’m teaching you guys to suck eggs, you guys are probably very well versed in occlusion and splints already that’s why you listen to this podcast but just for those students maybe or younger dentists who really didn’t get those lectures at dental school A Michigan appliance is a hard appliance okay? So the top is Michigan, lower is a tanner. It’s a centric relation appliance so it’s built into centric relation what that basically means is that when the patient bites together on the appliance, their jaw joint should be in centric relation and if you want to learn more about that listen to episode 20, Episode with Dr Kushal Gadhia if which is called if you’re not in CR, you will die. It’s a tongue-in-cheek title but check that one now we go into definitions of central relation there so basically when you bite together the condyle is in centric relation and that’s essentially what it means but what it means for you as a dentist providing that splint is that it takes you a lot of time and care to adjust to splint to make sure that when the teeth and the splint come together that the condyle is in centric relation.
It’s also a full-coverage appliance so it covers all the teeth and when you bite together you want pretty much all the teeth hitting and when you go into any sort of excursion left-right or forward you want anterior guidance and it’s basically all the principles of a minimal stress dentition so basically you’re creating this textbook occlusion which you would want to give in any sort of rehabilitation you want to get, you know, shallow guidance on canines, posterior disclusion, equally shared loads, all the sort of stuff you want to do in a full mouth rehabilitation you would give into this appliance so it’s almost like a reversible way of giving someone the perfect bite. I’m going to talk about the mechanisms of action and how it actually works but before we go there let’s talk about what you actually need to construct a Michigan or a tanner appliance. Basically, you need an impression of the upper and the lower or a digital scan whatever you prefer. Now I tend to take these in from taking impressions I tend to take them in silicon. Alginates I just don’t trust anymore even with appliances. I used to know a technician who said send me anything it doesn’t matter but eventually when you find that the odd case the appliance is fitting the model but it’s not fitting your patient it’s probably because the alginate distorted and the model is not now an accurate representation of your patient. So really just stick to PVS or take digital scans. So you’ve got your models, you need to take a centric relation bite, a centric relation bite So whether you take it with wax or again with a silicone bite registration it’s up to you but you need to give the laboratory that information if you don’t give them that information then they’re going to just make you an appliance that’s in their MIP and then it just creates extra work for you when you’re grinding away so you want to give them that centric relation bite.
Now a really cool trick I can give you when you’re actually taking your bite record in centric relation within centric relation, within the arc of it is that if you can control the occlusal vertical dimension at which you record this bite record if you record the OVD at where you want it so for example for a Michigan appliance typically you want it 1.5 to 2 millimeters at the thinnest portion at least so typically between the upper second molar and the lower second molar you want at least one and a half to two millimeters because remember you’d be grinding it away and you don’t want to make it too thin a lot of times if you’ve seen failed Michigan appliances you’ll usually find perforations in this area so you want to have that minimum thickness for strength. So when i do it, I tend to use a leaf gauge, okay? I dyed it up and I put it in the front teeth and I sort of make sure that when the patient grinds together, grinds forward, grinds back, and squeezes that the minimum space at the back is about 1.5 to 2 millimeters and once I’ve got that space I do my centric relation bite at that required dimension What that means than the magic of doing this is that when it gets transported to the laboratory and they mount it using a face bow hopefully, a semi-adjustable articulator, they simply have to remove the bike record and build the appliance in that position. That way there is no error of opening up or closing the articulator so the best way to explain that is that every time because an articulate is not the mouth and the mouth is not an articulator, so if you have to raise the occlusal vertical dimension on an articulator, you’re introducing a potential error but if you can not raise or decrease or play around with the OVD at all it gives you that little bit more accuracy and I found this for sure. So that’s a little trick I’ll give you to record the centric relation might record at your or thereabouts your desired vertical dimension.
Now, I mentioned using a leaf gauge typically another way to do this is to use a lucid jig which is made of acrylic for example something like Duralay can be used to make one or even some snap or trim acrylic around the front teeth and when the patient bites together there are back teeth separated and they can slide around and you can hopefully de-program them while they’re in the chair and get their centric relation record so i’m not going to go into too much detail because it’s almost impossible in a podcast to do that but you recorded your centric relation bite you’ve got your scans, all your impressions, you’ve sent that and as I already mentioned a face bow is ideal. Now, have i made a Michigan splint before without a face bow? Yes, I have, and do you really really really need one? Well, you have to ask what does a face bow does and I think this could easily have its own episode but essentially to put it down really really simple it’s to relate your maxillary cast.
So once you’ve got your model it’s to relate that model to the hinge axis and really what this means is that if someone has like the maxilla that’s off to cant and if you don’t send a face bow and they just put it on an average value articulator they’re going to struggle to transfer that cant for example the maxillary cant to the articulator and when you get an appliance back you might find that it’s hitting on one side and not the other so you can still make one without a face bow but hopefully if you’ve done your face bow correctly that it’ll give you more detail for your patient compared to an average value articulator because now it’s on a semi-adjustable articulator and this will hopefully translate in to save time. Whether or not this actually translates to save time or not I’m not sure if there is a study that’s been done comparing a Michigan appliance and how long it takes to equilibrate with and without a facebow, if anyone knows of one that’s a really cool idea please send it to me but really if you want to give your technician as much much as possible they will use your facebow to actually mount the casts or models on the semi-adjustable articulator and hopefully that will give a more accurate representation of what’s happening in your patient although we know already that articulate is generally are nowhere near as what said that the best articulator is the TMJ in the mouth but anyway that’s a whole different discussion.
So in an ideal world, if you’re gonna make a Michigan or a tanner, it would be a good idea if you have one available to send a facebow transfer. Now I’m just like 10 or 15 minutes into this episode and i’m already kind of like regretting it because i’m thinking are you guys able to follow what I’m saying. Now for those of you who are very experienced have been loads of occlusion courses you guys will hopefully be able to follow me but I’m very mindful that a lot of this stuff people don’t like to listen to as much because it’s a bit too heavy so stick with me if you don’t understand anything please message me or i’ll recommend some recommended reading or make some more episodes that really go down into the basics, for example, i can totally do one about Facebow all day long, the different types and stuff but just follow me now and i’m sorry if I’m losing you.
So how does a Michigan splint work? So now you’ve sent all your records to the lab they’ve sent you back an appliance you’re going to give it to your patient but how does it actually work? Well, i’ve told you already it’s going to create a minimal stress dentition it’s going to create the ideal occlusion within an acrylic appliance so you’re not having to do all this work in a patient’s mouth, so this is all reversible in the form of a splint and really it goes into the principles of biomechanics, right? If you get the patient into anterior guidance in all excursions then that’s the furthest away from the temporomandibular joint hinge and because it’s a further away it’s that whole nutcracker analogy again the forces are lower and also the anterior temporalis muscle switches off when you’re grinding on the front especially when you get to incisors by then the muscle activity is significantly reduced and you’re furthest away from your nutcracker forces from the TMJ hinge so the whole lever concept.
So that’s basically how the main bulk of it works so when you bite together everything is shared when you clench it’s generally shared and on excursions, it’s all at the front not at the back to keep the muscles calm. So why do you want even contacts now it’s fairly self-explanatory right but the way my mind works is that i always think about okay what if an appliance wasn’t even contacted and I think once you understand this it really drives home exactly the role of a Michigan so for example imagine I made you an appliance and it was an upper Michigan except I got my acrylic bur and I cut it right in half so let’s say now you’re wearing a right-sided Michigan appliance and nothing on the left so that you don’t have anything between your left-hand side teeth. So now when you bite together and you’ve got equal contact on the right side and nothing biting on the right side picture this what happens when you clench your teeth together up against the splint okay so your muscles contract. When your muscles contract your teeth crash into the splint and the splint then causes the depend with the PDL of the teeth to compress because now your teeth are now absorbing the load and as you contract contract contract as you bite bite bite then the temporomandibular joint or the condyle can also give some degree of load to the glenoid fossa area or hopefully if you’ve got a healthy disc through the disc and hopefully through the middle part of the disk now that’s all happening on the right side where you have the splint.
What’s happening on the other side where you don’t have a splint? Well, you don’t have the teeth and PDL to absorb any of the load and your muscles are going hard so what happens is that the condyle is really soaking up all the pressure up against the disc and what if the disc I’m just speaking hypothetically here to help you understand what if the disc gets squeezed out or what if you’re doing some degree of trauma to your temporomandibular joint. So if you haven’t got balance think about what’s happening in each of your joints there’s a lot of pressure potentially building up on the left side as the muscles are driving that condyle up and all the force forces going up into your temporomandibular joint and not into the teeth and not into PDL that’s the theory and of course, the reason why we want posterior exclusion is that it switches off the muscles, we want anterior guidance and we prevent the back teeth taking lateral forces. We don’t want our back teeth to take lateral forces back teeth are designed for sort of to take stress down the long axis, so it prevents that and it hopefully prevents cusp fractures and stress down the cuspal incline, so that’s the idea you want to keep your back teeth out of it during any excursions. Are you following me so far? I really hope so because the next bit it gets a little bit more complicated, right?
So there’s a muscle called the lateral pterygoid and hopefully, that will be relaxed so the idea of Michigan and a lot of the spins is that it will relax the lateral pterygoid muscles okay? So i’m going to try and keep this really basic with the lateral pterygoid muscle because it can get really complex and you know like I said in a podcast version without any videos or dissections and whatnot, there’s very limited stuff I can share but lateral pterygoid muscle is basically a super muscle at a basic level, its functions are to help you open your mouth, help you to protrude your jaw forwards for example and also to wiggle your jaw or go into excursions left and right and the way that works is that when one or maybe the right-side lateral pterygoid contracts then you, your jaw will go to the right and if the left one contracts and the other one doesn’t your jaw will go to the left so that’s generally how it works with the lateral pterygoid. Now here’s the cool bit when it comes to why us occlusion fanatics care and know about the lateral pterygoid so much and why it’s such an important super muscle is because of this right? Remember in dental school when they told us that 90 plus percent of us we do not have our MIP being equal to our centric relation contact point.
Now there are so many different terms for all this and this is why occlusion can get so confusing right like there’s terminologies that are always involving, for example, centric occlusion used to mean your maximum intercuspal position but then the definitions take change and centric occlusion actually now means your first point of contact which I just referred to as a centric relation contact point so no wonder people are get confused with occlusion because of changing terminologies constantly. So 90% of us are MIP and our centric relation contact point is not the same so 90 plus the percentage of us have a slide, so we all or 90 of us have a slide from our centric relation contact point so when your condyle is within the art of centric relation and we bring or if you close our mandible within centric relation eventually the first teeth to hit will be your centric relation contact point and then your teeth will slide into your maximum intercuspal position and this slide could be horizontal, it could be vertical, it could be a little bit of both and essentially we all have a slide or most of us have a slide. So why is it that every time you close your teeth together and bring your teeth together that you don’t hit this cr-cp first and then sort of slide into your MIP? Why is it that we can almost predictably when we close our teeth together we have this muscle memory that our teeth will meet together as they should and we’re not sort of clattering on these interferences or cuspal inclines before we reach where our teeth like to meet together? There’s a reason for this and that reason is the lateral pterygoid muscle It remembers. It has these muscle engrams if you like that are almost programmed to take you to MIP hence why the term deprogramming. If you’re deprogramming someone essentially you’ve achieved the programming if you’ve relaxed their lack of pterygoid and what this means to you and me is you forget how you bite together. So if you’ve ever had an experience where maybe you’ve been scuba diving and after you come back up from scuba diving you bring your teeth together and you’ve hit someone in the back and it feels funny, feels weird, and then you sort of bite together a bit more and suddenly oh here i am i’m biting in MIP again, that’s your lateral pterygoid deprogrammed and then reprogrammed if you like so that’s why the lateral pterygoid is such an important muscle in terms of occlusion, parafunction, splints, restorative all that sort of stuff.
So bringing it back to the Michigan appliance, it is potentially a deprogramming appliance as well so that because we build it into central relation and we follow up and we adjust the splint we hope that when the patient bites together that they are in their arc of centric relation and their condyle is in its most comfortable snug position and at that point, that’s when we have an equal distribution of load and everything is in centric relation or in RCP for a very old term as well. So that’s how the appliance works as well because it’s built in centric relation and therefore your lateral pterygoid would have deprogrammed or relaxed with this appliance as well but this is not the best appliance to the deprogram like if you want to just de-program someone i think it’s a terrible appliance if that’s your main function there are so many more efficient ways to de-program someone than giving them a full coverage hard thick appliance to wear and to see them for several appointments and to grind and as their muscle relaxes you keep grinding and eventually you get to your end point it’s not a efficient way to do it and just quickly the way to think about it is that because you have this plastic this flat plastic at the back in between getting in the way of your bite if you like eventually once you wear it your muscles do forget your lateral pterygoid relaxes and eventually as your lateral pterygoid relaxes, it actually lengthens and as it lengthens, your condyle is actually going back into the glenoid fossa and reaching that magical centric relation position and as you keep adjusting it everything is now even so that’s how the appliance works your teeth essentially forget it has tricked or fooled your lateral pterygoid muscle.
So to recap it’s to create your ideal perfect occlusion in acrylic and also at the same time to deep deprogram your muscles namely the lateral pterygoids so that everything is now relaxed and everything is evenly distributed with the correct anterior guidance in place so again the minimally stressed dentition that’s the idea of the Michigan appliance for the top or the tanner appliance for the lower. It is a great all-round splint and it’s very useful in a lot of scenarios especially when I’m unsure of the diagnosis and it’s the safest one that you can give like if you’re not sure and if you want something to work give him a Michigan, give him a tanner. A lot of the diagnoses do respond well to a Michigan or tanner but there are some major drawbacks which I’m going to go into now so there’s a reason why I’ve got some beef with the Michigan or I’ve got a problem with the tanner and I’m going to go into that now and you’ll learn why i think it is an overrated appliance.
Number one so the number one reason why i think the Michigan appliance is overrated is because how many dentists are actually doing it properly like if you’re gonna do a Michigan or if you’re gonna do a tanner do it properly like DO. IT. ALL. PROPERLY. TEXTBOOK. EQUILIBRATED. Spend those hours equilibrating, verify, follow up your patient, bring them in again, check that when they bite together they are in centric relation or within the arc of the cr and that they continually have even contacts and they have a degree of freedom and centric and again i’ll go into that in some other episode and they have the perfect shallow canine guidance that’s enough to disclude the posterior. How many appliances have you seen which are actually equilibrated properly because i’ve seen loads that are just plug and play i.e hey i’m giving you a michigan splint. Here it is. Wear it. Goodbye. No care and attention has been given and there’s a reason for this right? There’s a reason why a dentist might not equilibrate a michigan and a tanner properly because of money okay? It takes time and if you don’t have the communication skills to bring that value to the patient of why you need to spend a few hours and and lots of money.
Now let’s talk about money right? When i charge for a Michigan splint I’m typically in the seven to 900 pound region sometimes more depending on the case because i have an idea of which cases might be tricky and i might need more time and more adjustments and more follow-up and which won’t be and some of my colleagues, some of my various team colleagues charge around about 2 000 pounds so you can do the conversions if you’re elsewhere in the world. This is when done properly an expensive appliance because it uses up lots of chair time and lots of expertise to get it perfectly equilibrated. So because of the fee being so high that a lot of patients won’t accept it, so the dentist sort of do a quick job if you like and give an appliance which really isn’t i mean they call it a michigan or a tanner it’s just a hard flat appliance or a hard appliance for the ramp but not built-in centric relation and there are some disadvantages of making appliance not in centric relation which i’m going to hopefully go into in one of the episodes soon but basically one number one beef i have with these appliances that most of them that I’ve seen and from what i hear of are not equilibrated properly for that reason oh and by the way i almost forgot to mention you know that rule that we have as dentists that whatever your technicians or laboratory is you multiply it by a factor of three, four or five and that should be your fee to the patient that’s absolutely rubbish okay because it completely throws out the bus your hourly rate. So you should charge not by this random rule that’s been made okay yes for some things it’ll work but really you have to think long and hard about your hourly rate and you could be making a massive loss if you’re doing michigan splints and you’re putting in the time effort and care to give them the best appliance and if you’re not charging appropriately respecting your hourly rate is very very important so bear that in mind.
Number two reason of why Michigan splints are overrated, okay? It’s a big one, okay? It’s one of the reasons why i noticed and i moved away and i started to really seek some answers i wanted to know are there any better or more suited appliances to achieve what i want to achieve, to protect my patients from the force of parafunction than a michigan and its compliance? Okay, i’ve told you already in previous episodes i’ve been embarrassed before when i’ve made someone an appliance and i’ve spent a good few hours to adjust it and then six months later when they come back the patient’s embarrassed because they’re not wearing it and i’m embarrassed because i feel terrible that i put them through that entire process and charged them a good amount of money and they just weren’t able to wear it because you know it’s not a comfortable appliance to wear. It’s full coverage is hard, it covers all your teeth and it’s thick, it’s not a sexy appliance none of them are to be honest with you and if you have one yourself you should be able to appreciate that i mean i had one made for myself because i wanted to sort of experience what it was like and it’s not great you know it’s not fun, it’s not sexy compliance is a major issue and going back to a couple episodes when i talked about which is the best splint remember the g-splint is a splint which is best suited for your patients diagnosis, so compliance is a massive issue. So who is going to comply the best? The patient that will comply the best is the one who spent a lot of money with you to do a rehabilitation and you’ve told them at the end that if you want to not have to repeat this process or full mouth rehabilitation again you must wear this splint and you give a Michigan splints to them they might wear it okay because they’ve just been through the pain of maybe a year and a half two years worth of dentistry, lots of units, several thousands of dollars of pounds and then at the end of it they think yes i better wear this if i want to avoid having a rehab again or my restorations fracturing right? So they might wear it or the chronic pain patient and this chronic pain patient who you feel that the michigan is the best appliance for them, they wear it and then they start to see some therapeutic effect and they’re out of pain wow they will love it and they are the ones who will wear it for life or as and when they need to so those are two groups of patients where you might see good compliance but how about most of our patients who are asymptomatic and you had already a difficult time convincing them that they have para functional issue and that they’re grinding their teeth and they had no idea about this and now you’re going to get them to wear this michigan appliance which i’ve told you already so bulky yeah good luck with that. This is why compliance is so poor we’re giving it to asymptomatic patients who may not be 100% convinced and their why is not big enough. So let’s recap, so far number one was it’s time consuming and expensive to equilibrate it. Number two was compliance.
Number three is to do with clenching okay? If you have a patient who’s a primary clincher and you give them a michigan how is that going to help them? Yes it might help their jaw joint some degree but if they’re a headache patient, if they’re a myofascial patient and you give them a michigan and they’re able to clench really efficiently and hey they have something between their back teeth between their second molars and remember the nutcracker analogy you’ve got something right at the back of that nutcracker really amplifying the forces and the muscles going to overdrive then that’s not great right maybe your clenching patients is not the ideal patient to have a michigan maybe they are the ones that should be having a different type of appliance.
So the patients who clench this is not the perfect appliance it may not give them any therapeutic benefit if their main issue is myofascial or muscular related and why would you want to increase the efficiency of clenching now we talked about a few episodes with Dr Andy Toy about the posterior guided occlusion or the PGO splint like if there was a reason that you wanted to increase their clenching intensity look for that splint.
Michigans are neither here nor there and really for primary clenches it’s really not indicated and actually those are the patients i’m convinced that it’s the primary clenchers who come in and the back of their appliance has fractured right if it’s only about a millimeter half thin around the back then they can come you know they can clench right through that so your primary clenches is another reason why michigan appliance is overrated you’ve got to get your diagnosis, right? Okay guys, we’re almost to the end of these disadvantages of the michigan appliance and you’re gonna love this one this one’s gonna blow your mind it blew my mind when i started to reflect on this okay?
So the fourth disadvantage of a Michigan appliance is the following right when you provide your patient with the care and the time to equilibrate this splint, bear in mind that most or all of the adjustments are happening when the patient’s lying down which makes sense right because obviously they’re going to be wearing it when they’re sleeping usually and you want to recreate that so all of the adjustments are done when the patient is supine and laying down. Now what about you when you’re sleeping what position do you sleep in do you sleep perfectly on your back? Some of you might. Do you stay like that the whole night Do this little trick for me, bring your teeth together, bite together, i probably shouldn’t speak while holding my teeth together but anyway bring your teeth together right and now what i want you to do is as your teeth are together i want you to tilt your head to the right okay if you tilt it right so now just sort of focus in on which teeth are contacting right and now head back to the middle and now tilt your head to the left and head back to the middle and now tilt your head forwards and all the way back stretch up okay and back to the middle. 97% of you will realize that actually the way that your teeth were meeting together was different every time right so isn’t it funny that we make this appliance when the patient’s laying down and peace you know people sleep in funny different ways right? They do funny things with their necks and pillows and they might be sleeping on their hand you know whatever they might be doing these funny things So how do we know that all these adjustments and all these sort of things that we’re doing while the patient’s laying down the chair is actually translating to how they sleep. Isn’t it funny when you think of it that way?
Now i don’t know how much truth there is in this argument i’m making but it just gives you some food for thought right because the other way to spin it is that actually it doesn’t matter which position they sleep in because when they’re clenching, grinding all the muscles sort of contract and stabilize everything and it really is irrelevant because the muscles win.
That is a suitable argument and i take that point but it’s just some food for thought, we adjust the appliance when the place is laying down but what happens when they sleep they may be sleeping in funny different positions which may negate or delete all the hard work of what the appliance is supposed to do for your patient.
Jaz’s Outro: Guys you finally made it to the end well done that was a really really heavy episode and i really appreciate that you listen all the way to the end and i’m going to conclude by saying that actually the michigan appliance or the tanner for the lower is a great all-round appliance but it has some massive disadvantages and it may not be the best appliance it’s good for when you’re not sure if it’s a joint or a muscle issue and you want to sort of cover all bases but really if it’s a primary muscle issue or it’s an asymptomatic patient or if it’s someone who you just want to prevent their teeth wearing away anymore then really there might be some better appliances that you could consider and that’s exactly what we’re going to talk about in the next episode. Join me as we talk about anterior midpoint stop appliances and the various other types of appliances there are as we go deep into that as well. Now in the nature of this podcast I saw, i feel as though i went deep into it and i hope you gained some value from that but there’s so much more i have to offer about this appliance so i’m gonna try and if there’s enough demand i can go into a bit more about you know facebows or whatever but i hope that gave you a good general overview of the functions of a michigan or a tanner and why they have a place in dentistry but really they are an overrated appliance and they’re not as awesome as they told you they were in dental school