Understanding AMPSAs Part 1 [Splintember] – PDP041

As Dentists we do not treat headaches – however, we can manage the parafunctional forces and you will be amazed at how many patients will reduce their use of analgesics after these appliances.

This is the big one….we finally delve deeper in to Anterior appliances as part of Splintember!

Need to Read it? Check out the Full Episode Transcript below!

Lets talk about these really evil devices [/sarcasm] – the anterior only or segmental appliances, the ones dental school told me to stay away from…

There are lots of names/derivatives/ and brands for these such as:

  • B splint or Dawson B splint
  • NTI /SCi/Mci
  • Bitesoft
  • FOS
  • E-splint named after Jimmy Eubank
  • or the umbrella term for this splint family which is called AMPSA

I have decided the only way to make this work for those that listen to the podcast on your commutes and while you garden is that I will urge you to go on to the Protrusive Dental Community where I will post example photos and videos of the various appliances.

If you have not listened to Episode 8 with one of my mentors Barry Glassman – I really urge you to, we talk about these appliances and whether or not they cause an anterior open bites.

In a nutshell – many dentists condemn this appliance. They believe that by having a splint only on the front teeth, that the back teeth will over-erupt or dentoalveolar compensation will take place.

Does that happen? – NO, they do not tend to cause a Dahl effect for the following reasons:

  1. AMPSAs are only worn during sleep
  1. Dahl effect you need bone deposition – its not going to happen from 8 hours a night!

I was careful with my words, I specifically said they do not cause an AOBs due to the Dahl effect.

Technically, ANY appliance can cause an AOB due to muscle deprogramming and condylar repositioning +/- postural changes depending on which camp you believe in.

You can actually predict which are the patients this might happen to – once again, from any appliance, but because the anterior ones are more efficient at relaxing the lateral pterygoids, this is why they are implicated for it.

How does it work and which records do you need?

The way it works is similar to the concepts or rationale of anterior guidance which I discussed in the previous episode.

By not involving the back teeth – you are furthest away from that powerful nutcracker AKA the TMJ, and also due to the proprioception from anteriors, you are able to switch off the anterior temporalis muscles.

What does this mean?

What records do you need?

Why do I like leaf gauges?

Find out all in this episode of the podcast – I will go even deeper with Part 2 – watch this space!

If you would like to join us for Occlusion2020 Virtual 2 day intensive program on 27th and 28th November, there are a few tickets left!

Join me in Part 2 where we will talk about:

  • Deciding upper arch or lower arch, or sometimes both arches
  • What is the difference between these various anterior appliances and is one better than the other?
  • Why even an AMPSA can be an overkill and which patients may actually benefit from simpler devices
  • How many of my patients have developed AOBs, which splints caused them, and how to manage such a scenario

Click here for Full Episode Transcription:

Opening Snippet:As dentists we don't primarily treat headaches but we can manage the power function now you'd be amazed about how many patients have stopped taking analgesics after i prescribed these sorts of appliances...

Jaz’s Introduction: Hello everyone and welcome to episode 41 of the Protrusive Dental Podcast. This is the fourth one i think for Splintember. We’ve already covered which is the best dental appliance so that was like the g splint theory, we also covered some basic TMD anatomy and the weakest link theory. I talked the last episode about why michigan splints are totally overrated and now this episode we’re going to focus on anterior only appliances

Now, if i didn’t piss enough dentists off already from my last episode about a michigan appliances being overrated, this is bound to lose me some more fans i guess but hey the truth must come out because anterior appliances are ones that dental school taught me, never to go near like these are evil evil appliances. Don’t make anterior only appliances because catastrophic things will happen and you will get sued and you will lose your license and you will be begging on the streets forever and ever. So this episode i hope will restore your faith in anterior appliances when correctly prescribed and this part one just really is the basic overview, what the functions are? What the mechanics are? And what records you need to make an anterior only appliance? There are lots of different types of these appliances on the market some by type of design, some are branded for example most common ones are something like a b-splint, NTI or SCI or MCI, same thing different branding there’s also called the FOS, the flexiorthotic splints which is pretty cool. The bite soft An e-splint and which is called a Eubank splint. A Dawson b-splint which is pretty much a b-splints. 

A dual arch version of these and yeah the list goes on and on and on there’s many different types but the umbrella term that all these appliances is anterior only segmental appliances come under is called an anterior midpoint stop appliance, so how about if it’s okay with you i’m going to call these appliances AMPSAs. So if i say AMPSAs you now know what I mean. So we’re going to talk about AMPSAs

Now this is actually the appliance that i wear every night and it’s for me, it’s a protective and palliative appliance like i feel better i feel more relaxed and it also protects my teeth against the force of parafunction. So for that’s the role it has for me i guess what i want to say before we dive right in is this episode i want to talk about each individual appliance but i’m going to save that for the next episode because it will just flow better but if you’re looking for photos like a lot of you are listening to me right now while you’re driving or why you’re gardening and you won’t you don’t get the visuals that i’ll eventually show so what i’m gonna do is all the different splints i discuss i’m going to show you what they look like and how they work and hopefully i’ll six a few videos on as well on the Protrusive dental community facebook group which is a private group it’s my way of making sure that no members of the public and patients come in just dentists only and especially those who listen to podcasts and once you join that if you’re not already part of it you’ll see all the different splits i talk about. So that’s where i’ll be posting all the videos and images of different splints. If you haven’t already listened to episode 8 please listen to episode 8 it is called Do AMPSAs cause AOBs? So do these anterior midpoint stop appliances, do they cause anterior open bites and that was with one of my mentors Dr Barry Glassman, it’s a really insightful episode all about this basically we did some myth busting i guess i will have to because if you haven’t listened to it i’ll have to summarize it very briefly in in this episode but it’s well worth a listen especially if you want to get deeper and deeper into these appliances. 

The Protrusive Dental Pearl today will make more sense if you listen to the last episode where i talked a little bit about the lateral pterygoid muscle. So the pearl i want to give you is any patient who has a history of joint issues let’s call it so something that’s perhaps intra-articular clicking joints and you’re going to be doing some restorative care or even extractions anything that will involve them opening their mouth for a long time it is really really important that you give them a mouth prop on the adjacent side or the contralateral side because the function of the lateral pterygoid is to keep your mouth open. Now a lot of these patients you’ll realize who are parafunctional when you’re doing work on them you realize that they start closing and you’re like can you can you please open up again and they keep closing and you keep nudging them, can you please open up again these very annoying patients and because it’s basically because their muscles are already in a state of being tired you know they’re already overworked at night, they’re parafunctional and they struggle to keep open and their jaw gets tired and start getting pain and it’s basically a lateral pterygoid it’s hurting because it’s already so knackered right? 

So what can you do if you give them a mouth prop, it allows them to relax they no longer have to stretch open the whole time. They can relax into it. It gives an opportunity to for the lateral pterygoid to have a break and it also prevents the muscle going into spasm because what happens if it goes into spasm it will pull the disc even more forward and then they might have a lock jaw as in a closed lock and that’s not a nice situation to be in straight after dental procedure maybe this has happened to you before after root canal or long procedure that your patients are unable to sort of once they’re close together they’re unable to open again because they’re feeling a lot of tenderness on pain on one side. 

So it’s a great thing to do for anyone with a history of internal derangement to give them a mouth prop because it will help the lateral pterygoid. So that’s a the very relevant Protrusive Dental Pearl I have for you today.

Main Interview: So back to AMPSAs this appliance is actually condemned by some dentists because they believe and this is very principally, fundamentally what they believe is basically because it’s an anterior only appliance they believe that it will act as a Dahl appliance whereby it will cause the posterior teeth to over erupt or perhaps a degree of dental alveolar compensation and therefore your patient will get an anterior open bite. So that’s the main sort of those people who are against anterior appliances, that’s their main argument that yes it causes AOBs and we want none of it so that’s their main argument but really i’m going to do a bit of myth busting following on from episode 8 that actually that’s not quite accurate. Two reasons, one is that your patients who you give an anterior midpoint to appliance to they only wear it in their sleep. Now if our patients are only supposed to touch their teeth for 17 minutes a day and maybe about three and a bit minutes at night time only on average based some studies then really they’re only really missing out on three minutes of teeth concept per day for the non-para functional patient, the para functional patient is it’s a god send, this appliance because their teeth are no longer rubbing together but because they’re only wearing it for maximum you know 8-9 hours of night time then really that’s not enough time for a dahl effect to take place and number two is that this sort of Dahl effect it actually requires bony deposition i.e you the the body needs to lay down some alveolar bone to allow the posterior teeth to sort of overrupt or compensate and really this needs more time you can’t achieve this in 8 hours per night, ask any orthodontist. 

So this is a fundamentally flawed concept that you get a Dahl type effect and it’s really false and if you’re if you’ve been afraid of this appliance for that reason then don’t be but you can still get an AOB not from the dalh effect that’s why i was very careful to say you don’t get an AOB from the Dahl effect but you can get an AOB in any appliance, you can get an AOB from a michigan appliance one of my patients believe it or not she came to me with a posterior only appliance which should in theory cause posterior intrusion and a posterior open bite but she came to me with an anterior open bite. You can definitely get AOBs in any sort of appliance and the mechanism for that is nothing to do with a Dahl effect, it’s called condylar repositioning and that’s the most common theory. I’m just gonna go into that a little bit now. So remember back to the last episode where i talked about the lateral pterygoid muscle deprogramming. Imagine we deprogrammed your lateral pterygoid muscles those poor little stressed out positioner muscles, these super muscles are tired the whole time keeping your condyle in the correct place so you don’t keep crashing into your centric relation contact point and also doing parafunctions working really hard and now we managed to de-program it. 

Let’s say we give you an appliance any appliance and this deprograms your lateral pterygoid. 

Now what happens is that when you remove the appliance the lateral pterygoid forgets how you used to bite together and because it forgot how you used to bite together and it really likes this new situation it doesn’t miss the tension and the stress of the old position, it’s now relaxed and you know what it’s happy that it forgot the the old position and now the muscles are suddenly relaxed and the consequence is that actually you’ve forgotten how to bite together and because you forgot how to bite together you just bite together on your back teeth and maybe now you have an anterior open bite this is a real gross simplification of the process but essentially the best way to remember it is that your muscles forget how you bite together and this is called deprogramming or an anterior open bite due to condylar repositioning. There are a few more theories about how this actually works and a few other accessory theories about the other causes of AOBs with respect to splints but let’s just go with this one because it’s the most simple one and it’s the most common one actually. 

So you essentially forget how you bite together you can actually predict which patients are likely or a higher risk of getting an AOB whenever i’m prescribing these anterior only appliances in my notes i’m writing whether my patient in front of me is low risk or high risk of an aob and there’s certain traits for example if you’ve got someone with a ridiculously deep overbite they’re not the ones who are going to come in with an aob just accept it because if you can suddenly miraculously treat all these very deep patients non-surgically and suddenly take them from here to an AOB you’re a miracle worker, it’s not going to happen right? So there’s certain occlusals traits, there’s certain features of their dental anatomy which will mean that they’re more likely to have an aob and you can predict it and then you can write in your in your notes low risk or high risk and i’ll go into that in the next episode. 

The best way to figure out how anterior only appliances work is you know in the last episode where i talked about anterior guidance and the benefits of anterior guidance i.e being furthest away from tmj hinge and switching off the muscles, that’s essentially how anterior only appliances work that’s how AMPSAs work. They switch off the anterior temporalis muscles from proprioception and also they’re far away from the tmj hinge What does that actually mean? Well let’s do a little test, a little experiment, if you’re hopefully not driving and you’re able to do this if you can get yourself a clean covid free pencil or something like that or if you’re in the clinic get some cotton rolls, get a couple to disclude your back teeth basically so you put your pencil in your front teeth or around about your incisors or the cotton roll at your incisors and i want you to put your fingers by your anterior temporalis i want you to squeeze together with the pencil or the cotton rolls in place and feel the contraction, feel the contraction of your muscles 

Now do the same thing without the pencil or without the cotton rolls there and notice the difference, you’ll notice that your anterior temporalis muscle can contract significantly harder when your back either touching and that’s essentially how the appliance works. The muscles can switch off and if your back teeth are no longer crashing against each other then they’re going to be happy, the PDL is going to be happy. You may actually get improvement in sensitivity, if that was the also due to some parafunctional issues, you’re not going to be breaking restorations anymore because the teeth aren’t touching anymore Sometimes i’ve had patients with headaches tension type headaches and i gave them an appliance like this for muscle reasons and perhaps protective reasons and they come back and they tell me how their headaches have improved and they’re taking far less analgesics and ibuprofen because of this appliance now they’re no longer getting their headaches or it’s significantly reduced which is which is great to hear but remember guys we as dentists cannot treat and should not treat headaches right i always tell my patients i’m not someone who treats headaches i treat  parafunction and even then i don’t treat it. You still parafunction. I just manage the forces so that they’re now directed somewhere which is safer and better and not damaging your joint or not damaging your muscles so that’s the idea and some of these patients will actually get a secondary benefit i.e their headaches will get better in fact the funny thing is there’s a website called solvemyheadache.com and this is not a website for some analgesics or a massage therapy program it’s actually for a splint. It’s a splint i quite commonly use it’s called the FOS appliance FOS, flexiorthotic splint and it’s the sort of the patient-facing website marketing the FOS which only a dentist can prescribe so it’s not like they can buy it themselves but it’s it’s a great concept you know. They found out that these sorts of appliances your SCIs, NTIs, MCIs FOS appliances, they really help a lot of patients with their tension headaches but as tempting as it is you shouldn’t promise your patients anything to do with headaches. Don’t even go. Don’t even go there just tell them all with headaches that they need to get an official diagnosis from their GP, you are going to treat the problem that you see in front of you which is worn teeth parafunctional myofascial pain you’re not there specifically treat headaches but you might get a positive benefit. 

The other way to think about these appliances is you know that patient where you want to check their guidance right you want to check are they canine guided? Are they group function? What’s going on and you tell them can you please grind to the right and they tell you ‘yes i’m trying and they’re really just they’re locked in position and the mandible can’t move because the interlocking of their teeth is so good it’s so well meshed together the the inclines of their cusps are so steep and they just can’t move and and you think how is this possible, they’re clearly parafunctioning and going into those movements at night time because their canines are really worn so you think what’s going on here they’re locked in. 

Now what locking in does is that increases resistance in your muscles therefore when you give an anterior only appliance and they’re able to skate around freely you suddenly reduce resistance you’ve actually really helped these muscles in a way that an analogy i can give you is imagine you’re lifting some really heavy weights right and your muscles are are working overdrive and they’re working really hard to lift these weights and now suddenly you decrease these weights by about 75 percent those next few reps they’re going to be really easy it’s going to be like as if all the resistance has been removed and you can imagine your muscles will be in a happier position so that’s another way to think about how these muscles do work and how beneficial they can be for your patients. Those are the mechanisms of actions and really the indications for this AMPSA type of appliance is when you have a myofascial or a muscular diagnosis you got these tension headaches which you don’t you’re not treating because they’re tension headaches but you’re really treating the signs of parafunction and you want to protect them from further wear, you may have a situation where you have a tooth that’s hurting or you’re getting some sensitivity and you just can’t explain it and you think could it be because they’re parafunctioning and that’s the cause of it.

Now by giving an anterior only appliance if the pain goes away then you can to some degree of confidence agree that perhaps it was the appliance or the change or the existing occlusion or the occluding scheme that was the cause of the pain in the first place, so it can be used diagnostically of course anterior only appliances are fantastic de programmers far better than michigan appliances or tanners so definitely a strong indication for anterior appliances anytime you’re doing a rehabilitation and you want to deprogram them it’s a great appliance to give them to just reset all the muscles get everything relaxed so you can get a predictable centric relation recording. So those are the sort of general types of indications. 

I guess a contraindication will be joint issues and what i mean by joint issues is someone who can’t bear load on their joints someone who’s got severe pain and really if you give someone an anterior on your appliance when they bite really hard together yes the splint at the front is absorbing some load and therefore the pdl at the front is absorbing some load but all the other load if you like is is being directed to this, is the theory by the way, to the the tmj and if you have got an unhealthy symptomatic area with lots of inflammation, where your condyle may be impinging on what we call retrodiscal tissue i’m sorry if i’m getting a bit too deep into this but really if it’s a primary joint issue then this is not the ideal appliance however some of my mentors will disagree with that and they say you know what you can get away with a lot and very few patients have true joint issues that they will not be able to accept an anterior only appliance but if you’re starting out this appliance try and stay away from joint related issues and try and target patients with more of the muscular symptoms which actually is 90% of our “TMD” patients right? How many patients like i said a few episodes ago come in with raging tmj pain, very few primarily we’re managing asymptomatic patients thankfully. 

Now having said that if it could be a diagnostic event for you, if you give someone an anterior on your appliance and they come back with raging pain from their temporomandibular joint which by the way has never happened to me but that’s supposed to be pathomonic for someone who’s got a primary joint issue and perhaps you need to change your appliance to give them some “joint support”. Now again some dentists feel very strongly against what i’m saying here but i’m just giving you the theory that’s out there and of course you can also use AMPSA as protective appliances but really there are some other appliances which are cheaper and easier and simpler appliances which that you may wish to use as a protective appliance. I’ll go into a little bit more of that into part two. So now we know what answers do and when they’re indicated and potentially when they’re contraindicated and now i know that they don’t cause AOBs due to the Dahl effect but you can get an AOB from any appliance in certain patients who have certain traits right? 

So I’m going to go into that a little bit more detail next episode hopefully and throughout Splintember, where i can and on the Protrusive Dental Community but now you know all that. Let’s just talk about before we go about the records you need for this type of appliance. 

Now ideally if you’re starting out you should be taking gold standard records a to z. 

So the first record i take is the following this is something that was taught to me by one of my mentors Dr Michael Melkers right? It’s when you use a leaf gauge and i’ll probably be playing a video of this as I’m saying this to help you understand this i’m using a leaf gauge at the front and i’ll be dialing it down to find their first point of contact within centric relations so that centric relation contact point and essentially this shows me that if this program, if this patient was to deprogram what would their occlusion look like and if their muscles were to forget how to get back into their normal bite again what would they potentially look like so would they end up with an AOB? Would they not? How this look with the patient even realize and what you do is you take a photo of the patient with the leaf gauge in place at the position where the first point of contact is now. If it’s only a couple of leaves and they’ve got enough of an overbite then really they’re low risk but if they’ve got a shallow overbite, quite worn teeth and quite a big slide and they’re more likely therefore to get an AOB from any appliance that you do then that’s the one you want to take a photo for and show them as part of your consent then you basically have to figure out is your why big enough to continue with this appliance. Does the patient understand the consequences they will They understand that they may not be able to bite into cellotape again that they may miss the ham from their sandwiches and is the juice worth the squeeze because for a lot of these patients who are suffering a lot they don’t care about this bite change they just want a solution and at least you’ve predicted it and you told them ahead of time but i can reassure you now that these patients are not too common and i don’t want to scare you but it’d be irresponsible for me not to tell you this. So that’s the first thing i do and that’s a hat tip to Dr Michael Melkers who taught me to do this. 

Now of course you know already what Dr Michael Melkers doesn’t know about occlusion and splint is frankly not worth knowing and as you know he was supposed to come to london in May for occlusion 2020 and of course due to covid we had to reschedule that to November. Now a massive update i’m about to give you is that the event is still happening but we’re turning the event completely virtual it’s going to be occlusion 2020 live online two days full access to Dr Michael Melkers’ full immersion into full mouth rehab from single tooth building up to full mouth rehab and splints. 

So if you want to see these protocols and slides and cases and a lot more depth, join us for this online version in the comfort of your own living room or office or bedroom or in your pjs or whatever like before i was describing this event as occlusion and lamb chops and now i guess i have an option but say occlusion and pjs right? So join us for occlusion and pjs. I’ve reduced the price to £389 because we’re no longer having a venue Now, that fee of £389 is a massive massive steal compared to the 1.5k that i paid when i went to see Dr Michael Melkers in Stockholm in 2018. So join us for two days full online immersion into all things occlusion. Everything that was promised at occlusion 2020 but now in the comfort of your own home because frankly covid is really getting a little bit concerning so I didn’t want to pull the plug on the event because so many people are excited i’m getting emails and messages all the time, so we’re still hoping to run a really educational two days so come and join us. You can go to occlusion2020.com to sign up. 

By the time this episode comes out i probably would have made the ticket sales live again. The date once more is 27th and 28th november 2020 live online two days with Dr Michael Melkers. 

Let’s get back on track now so that was basically what Michael Melkers taught me which was the bite record of, if your patient was to get an aob would that happen, what would they look like and then show your patient that photo. That’s the first record. It’s a good screening thing to do to see if the patient in front of you is high or low risk of getting an aob after your anterior only appliance 

The second record i take is to measure the lateral excursions, protrusive and retrusive and the reason to do this is medical legally it’s a good thing to do before you give any appliance so that if in the future the patient says oh i i’m no longer able to move my jaw left and right,whereas actually you’ve probably improved their their function and you’ve improved their ability to move left and right but if you have some measurements you can objectively back that up right so what i use is a perio probe like a williams probe and i measure from the upper midline to the lower midline and i get the patient to grind all the way to one side and measure the sort of distance and then you either add or subtract based on if they have a midline deviation if they have a midline deviation obviously you need to add or remove a couple millimeters depending on which side they’re going to and essentially you make a note of this in the patient’s records and you can send that as part of your lab work as well So the lab knows what their range of movement is. 

The next thing of course is a record of the patient’s jaw so i.e an impression or some digital scans ideally if you’re taking impressions take pvs it’s just better quality and less chance of distortion of the alginate for example just be mindful of getting these drags technicians hate these drags that you can get so make sure your impression technique is good. So you want to send some impressions, you want to send the measurements you want to screen the patient like i said for a potential aob. You don’t need a facebow you know you don’t need a facebow because at the end of the day it’s just biting at the front so really these appliances are quite easy to adjust and a facebow is just not necessary you don’t even need a centric relation bite because when the patient bites together they’ll eventually get centric quite easily, they’ll deprogram very efficiently so you don’t need any fancy bite records. Very few scenarios you might and we might touch upon that next episode but generally that’s all you need. 

So I hope you found part one very useful that i just gave you some indications and which records you need and a bit of background about AMPSAs and why they’re potentially frowned upon and why these dentists who frown upon them maybe don’t have the best argument because really it can’t cause an aob due to a Dahl effect. 

Jaz’s Outro: Now in part two i’m going to cover some of these appliances and put them up against each other like why would you choose one type of answer over another. Which is the best AMPSA? Perhaps we can cover that i’m going to talk about decisions you have to make in upper arch versus lower arch versus dual arch so you can get dual arch AMPSAs as well and when would that be indicated. I’ll share with you how many of my patients have developed AOBs. Which splints were responsible for those and how i manage those patients and i’ll even tell you when an AMPSA may be overkill and maybe there may be simpler appliances like a soft bite guard Can you believe i just said that and we’ll talk about that in the next episode. So thanks so much for listening all the way to the end and join me in part two of understanding AMPSAs and i’m hoping you’re enjoying splintember. Thanks so much for tuning in

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Jaz Gulati
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