Hello, my name is Gail Demko. I am here to speak to you about oral appliance side effect management. Dentists are now on the forefront of treating obstructive sleep apnea with oral appliances and they come with a number of side effects which we're going to discuss. I have no conflict of interest. And we're going to start with the chart by Nishigawa who looked at people who stopped using oral appliance therapy. Why did they stop? So our major reason for dealing with side effects of oral appliances is to make them much more comfortable for patients, but we don't want them to use these side effects as a cause for discontinuing therapy. What we have is predominantly that they're bothersome to use. Well, the patients were saying the same thing about, so it's really not much of a difference. The fact that they have little or no effect is really an important side effect and that's because oral appliance therapy is effective completely in fewer than 50% of patients. We're going to look at most of these topics individually. We're just going to skim over at this point excess salivation down at the bottom and that's over here. The reason for that is that this is an oral appliance being placed in the mouth is the same as a new denture. There's going to be excess salivary flow. It goes away on its own. I want you to note that changes in occlusal alignment was not a primary or related cause for anyone discontinuing therapy. We're going to break these down into are the side effects temporary or are they permanent? Temporary is predominantly what we deal with. Permanent is a very small group and that's basically anyone who has permanent tooth movement. We're going to go over early occlusal alterations, pain of any sort, annoyance, and treatment ineffectiveness as each topic on its own. Patients will come in to you after wearing an appliance for as little as a week and say, you know, my teeth don't fit together anymore. These are actual quotes from patients. Their complaints were that they couldn't bite their cuticles or bite the cheese on their pizza, which tells me right off that they don't have an attack that was the same as they used to. You have to remember, just opening vertical dimension impacts the TMJ. That's just a baseline. We're going to get joint reaction to opening vertical dimension. If you look at CTs of patients who have a normal joint in a closed position, the condyle is fully seated in the fossa, there's room for all the soft tissue, and everything looks really quite nice. All you have to do is alter the inner incisal by two millimeters because you're changing more than a two millimeter opening because it depends on how much overbite the patient had. This could actually be a six millimeter change. The condyle doesn't always stay on a pure hinge, but starts to translate down the eminence. If you open them nine millimeters inner incisally, which I've seen on many an oral appliance that came in from other offices, this is going to have a significant difference as to where that condyle seats. Now, you have to understand that what we do is not just open the inner incisal, but we're going to move that entire mandible forward. There's even more impact on the condyle. Fernanda was the first to really look at this in 2002, where she did MRI studies on what happened when a patient's wearing an oral appliance. You can see in 3D data more that the condyle movement really comes down. She found that over half of her patients, the condyle moved to the height of the eminence, and one patient, the condyle was actually anterior to the eminence. We have some significant joint situations and changes, and that can lead to side effects. What happens to the soft tissue in the joint itself? Well, maybe we get morning edema that will build up when the patient is unable to seat the condyle, or ligament stretching, or just muscle reaction. What clinically will show is the patient comes in with a posterior bilateral open bite. As they move the mandibular incisors and the entire mandibular arch are held forward because of what's going on around the joint, they get an incisor prematurity, which will leave them with posterior bilateral open bites. It may be a unilateral open bite. That will be because one joint is more affected than the other with residual edema or muscle shortening. It may be that as they move forward, their occlusal scheme is such that they have closure of the posterior teeth on the one side, on the right, and an open bite only on the left because of the way the occlusion is. There's a whole group of patients that get anterior open bites. They come in. They say, I can't bite into my steak. I can't bite into a sandwich easily. Why would these patients be getting an anterior open bite when all other patients are dealing with a posterior open bite? That's related to the curve of spee. The curve of spee looks at the curve of the dentition up here. You have this situation where as the mandible comes forward, the posterior most distal molar starts to interfere with the distal molar on the maxilla. As it ramps down, that occlusal surface ends up with an anterior open bite. You'll see this in situations where you have missing teeth on the mandible. You have possibly an extruded first molar. As this second molar, which is now at a significant slant, comes down and hits that molar on the top, it's going to cause an anterior open bite. You can also get into what I call cuspal collision. As the mandible is held forward by whatever's going on in the joint, you get a cusp tip to cusp tip occlusion as you do on the bottom right, left. I'm a dentist. I'm dyslexic. You can end up with problems of fracture, whether it is an incisal fracture. You can also get fracture of the cusp tips in the posterior. Creative answers to how to deal with the fluid buildup, the residual thing that's going on in the TM joint, is patients will take it upon themselves to either lean on their jaw trying to force the fluid out. I had one patient who wore the elastic strap, as you can see on the right, as he was driving to work in Boston. He found that having forces along the long axis of the jaw did make a difference. By the time he got to work, the fluid was resorbed or whatever. Most of the time, we use full-arch morning occlusal guides. That is the most common usage now of making a guide for patients. You make them before they go into therapy so that you try to capture an occlusal registration of the closest they can get into habitual with material in between the teeth. They use this in the morning to guide that mandible back into its pretreatment position. To date, however, there is no literature that morning occlusal guides or bite tabs impact tooth movement, but we're hoping that they resolve the initial changes created in the joint. The use of morning exercises have been shown to make a difference. There are two articles out that look at morning exercises, one by Ueda and the other by Cunali. Both of these will show up as citations down below where you can go pull those articles if you want to see exactly what exercises they used. Those were done mostly to impact occlusal contacts in the posterior. Ueda was looking at improving contact points. The American Academy of Dental Sleep Medicine had a consensus meeting in 2017 to try and come up with how we treated common management techniques and dealing with oral appliance therapy. Daytime intraoral orthotics, maybe you would have a day guard. Most of the time it's just in the morning, but any prefabricated appliance was hopefully there to de-program the muscles of mastication and to reseek the mandibular condyle. Patients need to address occlusal alterations on a daily basis. If they don't, then the TMJ will not resolve on its own and you have a situation that can become a permanent situation. We use the pre-treatment morning occlusal guide, clenching, gum chewing, exercises, anything that will help resolve what we assume is edema in the TM. Then there's a group of patients who come in and say, I have no problem resetting my jaw in the morning. I have no trouble eating lunch, but by mid-afternoon, I find that my mandible is forward again. It's possible that this is foreshortening the lateral pterygoid muscle. It's a theory that has been touted for some time, but we don't know for sure that as the mandible is held forward for a six to eight hour period of sleep, the muscles that hold the condyle skull get used to being in that forward position. In the morning, when the mandible is then put back into its normal seated position in this condyle into the fossa, that the muscles now feel stretched and will foreshorten. Whether it's that or the patient is just working at a job where he's looking down all the time and we have gravity, that's unknown. Hard tissue problems often come from the mandible being forward. They're also due to direct orthodontic forces put on the teeth. Those are where we get permanent changes. If a patient comes in and tells you that there is pain in his teeth, that he can't wear the device because it's uncomfortable, you're going to relieve the internal aspect of the oral appliance. You're going to have them moderate advancement, hopefully, so that they won't put as much pressure on the teeth. Teeth break, crowns are displaced. We want nice retentive oral appliances, but I'm just going to draw your attention to be very careful about lone standing premolars. If a lone standing premolar is restored with an amalgam restoration or any type of restoration, you really don't know how much tooth structure is there holding things together. I would be very leery about having any sort of retention on a single bicuspid. I have removed crowns and bridges on a number of patients because the cement has washed out. I try to explain to the patient that it's a good thing that I did dislodge the restoration because now the dentist can check the integrity of that restoration and re-cement it as necessary. It doesn't make them happy that they have to go back to their dentist, but they do. If a patient comes in with problematic teeth, the patient on the upper left had a three-unit pin ledge bridge. Most of you don't even know what those are and that's because this was done in about 1950, but it was beautiful gold in the back and he didn't want to have to have it replaced, but I didn't want to remove that at his advanced age. I look for appliances that will allow me to window out or not contact problematic teeth, mandibular incisors who are already mobile. I will have various device choices depending on what problematic teeth present. Patients come in with all sorts of soft tissue complaints. They're common, but they're the least likely reason for discontinuing use. Tooth pain is going to be much more common, so adjustment of the appliance that's too tight or putting too many forces on the teeth is going to be something that I address first. Patient will come in and say, it hurts here by my joint, but on the inside, so I don't worry about the temporomandibular joint situation. I'm immediately going to do an exam intra-orally. What they have told me is I can't bite down when I'm wearing the appliance or it feels as if one side is further out than the other. It's just too big. What I will look for is now an ulcer here and that is going to be lateral to the pterygoid ligament area here and not related particularly to dentition. Look at the anatomy and think about where soft tissue is and why that could be a problem with ulceration in the posterior area on the cheek. It's quite possible that the width of the oral appliance you have given that patient is actually interfering with soft tissue anterior to the ascending ramus. If you look at how the teeth overlap with the anterior ramus, so ramus is here, third molar is here, you have buccinator muscle, masseter, pterygoid, you have mucosa, you have glandular tissue. Even though there may be 13 millimeters between the buckle aspect of the third molar and that leading edge of the ramus, you have open space of less than four millimeters. When you look at the contours of the device you use, you have to really determine whether that is a problematic situation. The lateral hardware can make some appliances be anywhere up to eight millimeters that they're taking up space. I have had a number of different devices cast for me because I use a full service laboratory and having the cast is probably the thinnest. It's also the strongest, but you want to be aware as to how much space you have and how much material you intend to put in that space. If a patient comes in with pain and irritation made from the ascending ramus, I'm going to go in and hollow out as much of the hardware as I possibly can, but it may impact the strength of that appliance. I'm going to change the contour of the device to accommodate the surrounding tissue without being an impingement problem. To try and ward this off in advance, I will often put a mirror, typical mouth mirror, lateral to the maxillary molars and ask the patient to move his mandible side to side. If he can run into that mirror head, I'm going to have trouble. That will tell me that if he feels that as he goes into protrusive and moves side to side that he can feel my mirror head, I'm going to think about using a very narrow appliance in that buckle aspect. What if I have plenty of room and the patient comes in with similar complaints? They can't bite down because it hurts near their wisdom teeth. There's all that room. Now, I'm starting to look for retromolar pad impingement. I'm a little bit further back on a tissue that comes up distal to the lower molars. You can see that it can appear at placement or as the mandible is further titrated. Now, once you put an oral appliance in there, that retromolar pad tissue comes right up against the maxillary segment of your appliance. The compression can go on for about a millimeter or so that the patient will notice something there, but it won't be annoying. At some point, it's going to be extremely painful as that retromolar pad is jammed up against the oral appliance. I'm going to shorten the maxillary aspect of that appliance. I'm just going to take off any coverage on that distal molar, knowing that it's going to impact all sorts of other things from retention down to tooth movement. To get an idea of whether I think I'm going to have trouble with retromolar pad impingement, I'm going to look at the impressions that I've taken. On this alginate down here on the lower left, you can see I have very little lateral tissue for hardware. I would expect problems there unless I put in a very thin appliance. On the upper left, I have that large buckle shelf. I have to be aware that the device itself is going to stop right at the gingival margin. That may impact all sorts of things from retention to hardware placement, but I'm not going to get problems with any interference with the leading edge of the ramus because it's going to be well outside where my dentition is. What is going to bother me is this one on the lower right where I have two molars and goes immediately up into the retromolar pad. It was almost a right angle change. That's the patient that I think I'm going to end up having difficulty with an oral appliance if I'm going to have any space or any material distal to that maxillary molar. Here, I'm not going to expect a lot of problems because the retromolar pad is back even further. The mandibular impression here is going to tell me I can't wrap that distal molar, so the device is going to have to stop here. That's going to lead to all sorts of tooth movement. You may wish to fabricate the device with the maxillary portion short of the distal aspect of the upper molars, but try to never shorten the mandibular portion because it is that ability to wrap the distal molar on the mandible that helps with tooth movement in a permanent basis. All devices have allergenic potential. It doesn't matter what device you're using, whether it's methyl methacrylate or nylon, there's something that causes allergies in almost every patient. To avoid that is critical. You're going to ask ahead of time if they have any sort of nickel allergies, but other people come in knowing they have latex allergies. Others find it out after you use elastics to help hold the mandibular and maxillary segments closed. These are patients who have various types of allergies, which we found out by giving them an oral appliance. This patient never knew that he had a latex allergy until we put him in an appliance that had latex elastics holding the maxillary mandibular portion forward. This patient has an allergy to the dye on a strap that holds the mandibular segment forward. This patient, methyl methacrylate dye that was noticeable because the palatal hardware of the appliance was attached with a salt and pepper technique. This patient is allergic to metal. These are screw head markings from Herbst hardware. You want to look and be aware that if it's an allergy problem, if it's latex elastics, you just go to non-latex, but if it's the integral to the design of that device, you may have to consider changing oral appliances. Now we're going to discuss a bit more in depth just the joint and not the occlusal problems that come about because of it, but you want to be aware of what we are doing to the TMJ when we place a mandibular advancement device. Michel Doff did his doctoral thesis with three articles on TMJ problems, and he looked at two-year follow-up on a controlled study at the side effects. His hypotheses were that there was strain in the muscles of the temporomandibular complex or the capsular ligament when protruding the mandible during sleep, that just the increase in vertical dimension is going to impact the joint as we mentioned before, and with the condyle positioned forward out of its natural resting position into a more forward position, there could be resulting strain on the retrodiscal tissue. It does not appear to be that there's any inflammatory component in most patients since there's rarely pain, tenderness, or swelling. But Fernanda did find that in some patients there would be small osteophytes. In one of her seven patients, she found thinning of the cortical bone in the condyle on MRI. Doff hypothesized that temporomandibular complex has adaptive capacities, which we've known in many patients, to the unnatural protrusive position, and that, therefore, these appliances may actually be therapeutic in patients who come with active TMD prior to treatment. Nishigawa found that the average prevalence of 34% was noticed patient, pardon me, the patients noticed TMJ symptoms of some sort, but it was never the primary reason for discontinuing oral appliance therapy. Unilateral TMJ pain has myriads of possibilities as to what's causing it. It may be a problem with midline alignment, that as the patient moves forward, he naturally would become eccentric, and the appliance was not allowing for that eccentricity, or that the bite registration we took captured the patient at an eccentric position when he normally didn't protrude eccentrically. It could be that the appliance is now unevenly advanced, and one side is further forward than the other, causing pain in the side that is further forward. It could be that as the patient moves the mandibular segment forward, that occlusion that we originally balanced to make sure that there was bilateral simultaneous contact between the maxillary and the mandibular segment, that this is now no longer bilaterally symmetric, or sleep position. There are a number of patients who wearing an appliance that allows free lateral movement, which some of them do, will find that when they are sleeping, the mandible is now pushed eccentrically, and this causes joint pain. So the summary on joint pain side effects was there's no real morphologic change in the joint other than minor osteophytes, and that it's proven that over a period of one year to be innocuous to the TMJs of patients with sleep apnea. Annette Franson, as part of her doctoral thesis, found that at baseline, the 34% of patients with joint noise or muscle tenderness were actually improved or unaffected negatively over a two-year period. So we have one in two-year data. Michelle Doff was two-year data, and found that the initial stages, there may be transient difficulties wearing the joint, where wearing an oral appliance because of joint pain, and what you're going to do is back off advancement, slow down advancement, adjust the appliance to make sure that all the contact is bilateral, that the patient is not allowed to move eccentrically too far, and that functional impairment of the TM complex appears limited of the long-term use. That Gianassi found that prior to treatment, that long-term, it didn't cause any sort of TM joint problems. So common management techniques for TMD complaints from AADSM are verification of the occlusion to make sure it's balanced, alter vertical opening if needed, and that is both making it more or making it less, depending, isometric and passive jaw stretching exercises as noted by Cunali and Uyde in their articles, and conservative titration, slow down, don't move them as quick. Instead of having them move a millimeter every week, they're going to move a quarter of a millimeter or a half a millimeter forward. Slow and steady wins the race. So guidelines for all side effects from AADSM are palliative care. That means you make the patient feel comfortable, whether it requires resting the joint, icing the joint, going to a soft diet. The use of topical and systemic pain relief medications are basically Advil. Getting into anti-inflammatory medications, massage and physiotherapy is well beyond the can of anything I ever did in my practice. Watchful waiting is another part of care of these patients, which means you see them when they need to, you talk to them when they need to talk to you, you observe what's going on and try to diagnose if it's a simple thing to fix, such as impingement of soft tissue, but indeed they may need to go back and have another sleep test. You have to understand what's going on and its implications and how it impacts the stomatomathic situation. Documentation is important, especially with persistent side effects, how they're resolved and management of the problem. Be aware, pain is never a permanent side effect because you either adjust the device, go to a device that's not gonna cause the same problem, or suggest that the patient discontinue oral appliance therapy and go back to see the physician for alternative therapy. The minute a patient resists this, saying I'm not gonna go back on CPAP and I'm gonna work with my oral appliance, that's when you tend to see side effects resolve. There are other complaints, and most of this has to do with that it's just bothersome to use, such as it won't stay in or it won't come out. For patients who can't put it in or can't get it out, you wanna make sure that the patient doesn't have arthritis in her hands that preclude being able to get this device off or on. For hard appliances, rigid appliances, there's a path of insertion, just like with a removable partial denture. And if the patient's unable to figure out what that path of insertion is, they all wanna put the device in and just bite into it, something that we shouldn't recommend. And so you have to help train the patient to find that path of insertion. Some appliances require heating and warm water prior to placement, others say don't ever heat it. Some say warm it up before removal. There are other patients who can't get their fingernails underneath the edge of very thin appliances and may have to have removal buttons placed. So if the lower portion only is overly retentive, if the patient just finds that when it's on, it's really pressing on the dentition, that it's very hard to get it off, it may be related to impression technique. There are studies that for years have shown that the wider a patient opens, the more the mandible has a tendency to flex and become narrower. This was certainly made obvious in this article from 2000, where an impression made with a patient with his mouth wide open and a dentureless patient restoring implants, the casting didn't fit. So when taking a mandibular impression, if you're doing wet impressions and not digital, you want to support that mandible in a less open position to prevent that flex. Other patients will say it's too tight, but I left it in my car after my last visit, I dropped it in hot water, my husband did the laundry and it went through the dryer. I have seen all sorts of appliances come back in very odd shapes and distortion, all because of patient error. And again, you may have to remake this appliance. It may not be something that you can adjust simply. If the patient comes in and looks at you and says, you know, this comes out at night, it won't stay in my mouth. It may be under retentive. So these are the five reasons that I have come up with as to why the devices will be dislodged at night. If it turns out that it's the mechanics of the oral appliance, that the elastics themselves that I use to tie the maxillary and mandibular segment together, actually pull in the path of withdrawal. This will be dependent on the angle of the retentive dentition, or the appliance was simply poorly retentive. If the device itself is non-retentive, I would use monomer and powder, triad material, whatever, to increase retention interproximately. As you can see down here on the lower left, I had to extend the height of the acrylic well onto soft tissue in order to get enough retention. With nylon appliances, I would simply alter them as others have taught me with the heated pliers to increase interproximal retention. Proper extension makes a difference. So we have appliances that are less likely to be retentive when you're missing wrapping the distal of the mandibular molars. I like to have the distal molars wrapped simply because, and these are, as you can see, this is a first molar. I want to have that because it will resist the possibility of dislodging an appliance from forces as long as I have all four sides of the teeth and the dentition wrapped. If the problem is path of withdrawal, you have to look for these dislodging forces with different devices. So here I have a patient who had real trouble with the appliance that I made him on the left. It was simply not retentive on the mandibular arch where less than two millimeters of height showed up. The difference was I had about 10 millimeters of height of tooth structure on the lingual. Put him in a device with a different path of withdrawal and he had no trouble with retention. So this is, again, look at your appliances. Do you have a direct up and down dislodging force whereupon flared incisors will resist that retention? And tendency for dislodgement? Or do you have an angled force of withdrawal and dislodging force that will be much better resisted by other angulation in the incisor area? Some teeth provide no retention. It doesn't matter. It can be both lingual and buckle. It can be just on the buckle because of loss of enamel. So in some patients you can go in and add composite buttons on the buckle aspect of the teeth for retention, but those can be knocked off and you're going to be replacing those frequently. There are some patients that you look at and say you're not a candidate for oral appliance because of the shape of your teeth or the height of your teeth or the gingival positioning. Does the patient remove his device as he did his CPAP? So patients who come in and say I can't wear CPAP because I took it off in my sleep, those same patients and other patients can take off their oral appliance and will wake up in the morning finding it very carefully on their bedside table or hiding somewhere in the bedclothes. If I have unilateral contact at night, it can destabilize the device and cause it to come off and so can significant ruxism, but that is going to be evidenced more in say a dorsal type device where you're going to break those. There will be complaints on some appliances and with patients of lip incompetence, dry mouth, lip discomfort and appliance bulk. So part of that is going to be what did my lab send me and what did I ask for? I used only two millimeter and five millimeter bite forks from the George Gauge. I happened to adjust them appropriately so that when the patient was biting into the bite fork, I could measure that the incisors were only two or five millimeters distant from each other, but that doesn't have a lot to do with what comes back from the laboratory. As you can see here on five millimeter and two millimeter bite forks, I got all sorts of inner incisal distances back from the laboratory, depending on how the laboratory technician took it upon himself to change my bite registration to make it easier for himself. And so I'm very careful that every time I placed an appliance, I went back and measured to make sure that the inner incisal distance that I was getting back on the appliance matched what I sent to the laboratory with a gauge, or I would send the appliance back to the laboratory and say, all right guys, you are going to grind this down or remake it to what I asked for. It could be device design. If a patient comes in with lip incompetence, nothing you do is going to make those lips competent because you are going to open the inner incisal distance by putting material in there. In this case, if I had a lip incompetent problem, I would look for an appliance that tends to seal the incisor area to prevent dry mouth. There's another catch going back to that curve of spee is I have to be careful how I take a bite registration because if I take a bite only in the incisor area, maybe back to the bicuspids, I could conceivably come up with a bite registration that fills this distance. So I have my two millimeter inner incisal distance here. I have bite material here that says, okay, mount this case. The laboratory mounts the case with the bite I've given them and find that I already have contact in the posterior area, but I've asked them to wrap the molars. That is a real problem. So if I have a steep curve of spee on a patient, I may be asking the laboratory to do something that is impossible. So you want to look at patients like this and say, if I'm going to get a change of the typical one to three relationship that we have with dentures of a two millimeters for acrylic back here, that's going to be a six millimeter change here. I'm going to have to go to a bigger bite fork. I'm going to have to use an appliance that will allow me to window all the way down to tooth structure without changing the integrity of my oral appliance. Very difficult to do, especially when you're using a printed nylon appliance where the demands are for two millimeters of nylon over each distal molar. Now I'm going to have a four millimeter change back there. So it becomes problematic if I'm not aware of what that occlusion is like beforehand and whether there is that steep curve of spee, which is going to mean I should probably change from my favorite device to a less favorite device simply because I don't want to make that patient have more problems than necessary. This is a typical model that comes from a oral appliance company that says, hey, this is how our appliance fit. Isn't that beautiful? So here they have now a four millimeter space between the distal molars. We know that that four millimeter space would not translate to a three millimeter space inter incisely unless they have a wicked over jet, overbite, but it's going to mean that we're going to have a change of about 12 millimeters in that area. Secondly, neither of these appliances wraps the distal of the molars, which means that retention is going to be problematic if I put elastics on there to prevent the patient from opening at night. Some are going to come in and complain, you know, I don't feel any better with your oral appliance. And the things that I would look for are the four, steep mandibular plane angle, incorrect vertical, either excessive or inadequate. And I know that 50% of patients are inadequately treated with oral appliance therapy, and maybe the device just doesn't work very well. Steep mandibular plane angles are a problem. Going back to what we were just discussing with the curve of speed, that if three millimeters of material were placed in the posterior region here, the alteration in the interincisal actually will drive the attachment of the genial glasses muscle back and downward, compromising his airway. In my 20 years of doing oral appliance therapy, I was able to effectively treat only one patient who had a steep mandibular plane angle. So when you see patients who come in with a very steep mandibular plane angle, you have to be very careful about how you talk to them as to success rates, because they're going to be extremely low. Other hand, patients come in with a very normal mandibular plane angle, but the oral appliance has opened them phenomenally. I've seen patients come in with appliances from other dentists where they were open upwards of 15 millimeters interincisally, regardless of their overbite. So again, this is on the skeleton, we're using that as an example, the little white box is approximately the attachment of the genial tubercles, that when the patient is in a closed position, the genial tubercles align pretty much with the first bicuspid on the maxillary arch. But if they open widely, now that same attachment is comparable to being between the maxillary first and second molars. So we can see how much of a setback that is. Radiographically, it looks like this, so that you can see the changes and even here in the airway size with the opening more widely. And Share's data showed that when you open the mouth interincisally 1.5 centimeters, that correlates to a one centimeter retrusion of the attachment of the genial gloss. So the more you open the vertical on many patients, the worse you can make some of them. Some respond well, but predominantly they don't. Other patients will come in and say, I don't feel any better, but my spouse is happy. My bed partner says that I don't stop breathing anymore. They tell me that I don't snore anymore, but I don't feel any better. Now you have to look at the fact that the device may be inadequately advanced to control their obstructive sleep apnea, that the device doesn't work at all, the same one we went through before. But that the cause of fatigue may not be the sleep disordered breathing. There's two articles that speak to that, one being Bixler and the other Pagil, where they looked at what causes patients to feel tired. Excessive daytime sleepiness is not tied strongly to obstructive sleep apnea. The number one cause of excessive daytime sleepiness is depression. The second most common cause is obesity. The third most common cause of excessive daytime sleepiness is just being aged or elderly. Sleep duration comes in at number four. Diabetes is the fifth most common cause of feeling excessive daytime sleepiness. Smoking was number six and sleep apnea comes in at number seven. So it's quite possible that your patient's problem and excessive daytime sleepiness is not being caused by obstructive sleep apnea. Other studies looking at controlled placebo studies where a patient wears a placebo appliance versus a patient who is getting active treatment of mandibular advancement, found that statistically there was no change in excessive daytime sleepiness in these patients. Same with CPAP. So just treating their obstructive sleep apnea with an oral appliance may not impact their excessive daytime sleepiness. If the device is inadequately adjusted, you have to make sure that the patient isn't confused about how to adjust the device, that they really did understand. Your staff should go over and have them demonstrate on an example device, how to make adjustments on that specific device. I've had patients go forward on one side and backwards on the other. They get written instructions with pictures and definitely demonstrate that they know what they're doing, but I measure position of hardware on every patient who comes back in for recall. Instead of having excessive vertical dimension, it can be inadequate for patients who are macroglossic. When I see a large tongue, there's two things I will look for. Number one, I will never put them in an appliance that has palatal hardware. If the hardware is going to interfere with tongue space, I'm not going to use that device on patients who are sitting with a Freedman 4 or potentially even a Mallum Patty 4 because both of them really look at tongue size. So on some patients, I've had to go with my typical two millimeter inner incisal bite and add to the appliance and improve inner incisal opening in one patient. And this is an example on the bottom right where I added to a 10 millimeter inner incisal distance and the patient put the appliance in his mouth, pushed his tongue forward into the space and said, oh, that feels so much better. So you want to make sure that the appliance that you've chosen allows adequate mandibular advancement. Do the straps, screws or other hardware allow for four, five, six, 10 millimeters of advancement after you start with your initial positioning. And if not, you're going to have to either redo the hardware or change to an appliance that does. Especially with the push nowadays to start the mandibular advancement at a much lesser advancement because side effects are much less common in patients who are moved minimally forward. And we know now that many patients are adequately treated at 25% of their range forward, especially mild. In a monoblock or one piece appliance, there is no adjusting. So you really have to move them forward and you may have more side effects in the initial placement of this. If you start them at 60 to 80% forward of their natural range, it may be a little bit more difficult for them to settle in, but it doesn't preclude it's being effective. So if your patient comes in and says, oh, I was fine, but now I don't feel as good. Now you have to go back and check to see if what has happened to the appliance. Almost always when a patient says he was fine and is now no longer feeling as good as he was, I'm gonna check device integrity. Hardware backs off, stretches out, nylon straps stretch. So I will make sure that the position of mandibular advancement is at least where it was the last time. And if not, do something to correct that. If it's broken, cracked, and I've had patients, and these are all patients who've come in to see me, so everything can break, and they are totally unaware, except when a dorsal fin comes off. They are aware of that because there's a piece loose in their mouth. But other patients may not be aware that they have had this sort of a problem. They can delaminate, they can get distorted, they can get dirty so that they're not retentive, and now they're no longer effective. The patient may not notice that he is out of that appliance all night long, and then the morning when he bites together back into the appliance, think that it's been in position all that time. The patient who allowed the calculus to build up on the inside of his Herbst appliance in the bottom right, ended up with major problems because this happened to decalcify all of his dentition. The lack of improvement may not be from the appliance, but to changes in the patient. So you have to look at patient alterations such as, has he gained weight? Has he changed his shift at work to increase income or productivity or to keep his job, and now is working nights as opposed to working second shift? Is there more traveling? Is there a new baby in the house? Has something occurred that this patient is sleeping five hours a night as opposed to the seven he was sleeping before? We're gonna get now to the only permanent side effect, and that's tooth movement. Tooth movement comes about because all of these appliances are bastardized orthodontic appliances. As the mandible is moved forward in an oral appliance, the patient will have muscles that want to pull that mandible back into its normal position, and that will put forces on the dentition. On the mandible, they're gonna wanna move forward. On the maxilla, they're gonna wanna move posteriorly. So what we have here from Almeda is that as the mandible pulls back, and this is the force vector created by the muscles, the forces on the dentition are forward and towards the non-dominant chewing side. So our muscles are not even as to how much they pull back. They're gonna pull back more on whichever side we tend to bite and chew, and so you're going to see teeth shift in unusual positions where we're not necessarily expecting it. The forces on the incisors are to make the maxillary teeth want to rotate backwards. Mandibular teeth will tend to procline forward, and this can lead to an interference in occlusion, but it is evident in as little as six months that orthodontic permanent movement has occurred. Clinically, what you're going to see is opening interdental contacts. That's gonna be much more common when the entire dentition is not wrapped and held together. So we have a patient here in about a three-year period, went from a nice closed contact to, as you can see, very open contacts, and that is something that is not going to be corrected or can be blamed on transitory TMJ situations. Permanent tooth movement will now cause alteration in interincisal contacts, just as we had with initial treatment, except there's nothing you can do to fix it. In the case on the left, the patient now became premature on his incisors. He did fracture that porcelain and ended up having to have all of his crowns in the incisor area replaced. We're gonna see open bites, posterior open bites, anterior open bites, that are gonna impact chewing. A worst-case scenario with a positive spin was presented by Alan Lowe, a tremendous researcher in this area, when he looked at class II patients. And you can see from the views on the far right that the overbite and overjet started to change. So as the mandibular incisors flared forward, causing spacing, the maxillary incisors started to retrude, there was a change in the patient's tooth position. Molar position also changed because the mandibular teeth moved forward as a group. It isn't just the incisors that move, it's also the molars and the entire dentition that start to shift forward and changed the occlusal classification, but also changed the patient's incisor relation. So what actually changes is the tooth position. Again, we're going back to my patient here, John, who in 1994 had beautiful class I occlusion. By 2004, I had him in class III occlusion. It didn't take me long to deal with that. And he continued to wear the oral appliance and was very happy with it. Why you need baseline data is there's actually published data from one appliance that says, hey, our really rigid appliance does not allow tooth movement. And what they show you is a comparison of pretreatment and post-treatment dental casts. So here with the patient in 2006, changing to 2012, the major thing that you're going to be seeing is increased rotation of that mandibular left central incisor. Other things changed slightly, but it didn't seem as though there was big difference. We don't see open contacts, we just see a change in the rotation. So somewhere in between, I actually had mounted casts about 2008 that show that this patient has now moved up to an edge-to-edge molar relationship predominantly, but you can't miss this in the mouth. So clinical evaluation mounted casts show you the real story, that this patient has come forward into a severe class III, so from edge-to-edge in 2008 up to 2012, and that is dental movement. You can actually see now the changes in the angulation of those incisors as they flatten and start to move backwards, and the mandibular incisors flare forward. Clinically, you're going to see this over a number of years. This is a person who happens to be a trial attorney. She is not at all concerned about what has happened with her occlusion over the 15 years now that she's been in the oral appliance. She sleeps well. She's happy. She does her job. She's hard, and she's driven, and she has a speech impediment. So that is her side effect from this, and I explained to her that going back to CPAP, going into orthodontics, and she said, absolutely not. She'll continue with her oral appliance. Luckily for me, her father is a periodontist and also said, don't worry about it. So she goes on rightfully wearing her appliance, but you can see the changes that have occurred over that period of time of treatment. So teeth may move differently based on the material devices. So the device materials come in with a patient. I had a number of patients, three actually, in a hard acrylic appliance that because I had elastics between the maxillary and mandibular segment, and there was reasonable retention on the incisors in front that they started to slip up and down and actually caused extrusion. In two cases on the maxillary incisors, in a third case on the mandibular incisors, the tooth extruded beyond the normal plane of occlusion. With patients who have flexible nylon appliances where the incisors are not held in a rigid position, you're going to get more crowding, more slanting and rotation so that you can see the mandibular right second incisor is now crowded back more fully out of the arch than before. That was within a year. But patients don't use tooth movement as an excuse for discontinuing therapy. The patient with the crowding on the mandibular incisors had the lingualverted incisor extracted and closure of the other space solved his problem. This patient has gone from a class two now to a more class one molar relationship and is exquisitely happy with the changes in his profile. So clinical findings related to permanent tooth movement is of course that there is tooth movement, but because of posterior interference of the molars, you tend to get an increase in face height. That also increases mandibular plane angle. We know that in all cases, there's decreased overjet and overbite, that this results in a possible posterior or anterior open bite that is now permanent. You don't want to change that. You don't want to go and have the patient restore that with three unit bridges in the back or higher crowns, because if they're going to continue wearing an oral appliance, these changes continue to occur. There will be a decrease in occlusal contacts, quite often a decrease in interdental contacts, but no one, and that's why we have all of this, these reference material at the bottom, there are no skeletal alterations and no negative TMJ findings. So skeletal changes are not clinically significant. And what Pliska found is that maxillary retroclination, that ability of the maxillary incisors to upright and actually recline into the oral cavity, increases at a constant rate, regardless of how long a patient is wearing that oral appliance. But mandibular proclination, the tendency of mandibular incisors to move forward towards the lip slows with time and appears to stop around 19 years, which he hypothesized was from pressure of that lower lip pushing back on the teeth moving forward so that we now had forces that equalized and the teeth stopped moving. The teeth that were upright at baseline rather than slightly flared forward were more susceptible to proclination with time. There is, however, large standard deviations and individual differences. So in some patients, there's a tremendous amount of movement, and in some patients, there's only mild movement. So what predisposes to permanent tooth movement? Well, the biggest predictor is how long they're in an oral appliance. Patients with 19 years of oral appliance therapy are going to have more tooth movement than patients with two years of oral appliance therapy. It's also going to be impacted by how long they wear that oral appliance every night, so it is adherence to therapy and sleep time, as well as the amount of advancement. So what Mona Hamoda and Hitomi Minagi found out was that the further forward you move a patient's mandible or have them move forward for effective therapy is going to impact tooth movement long-term. Interestingly enough, Hamoda found that more obese patients had less maxillary incisor retroclination, or moving lingually, because, and they thought, from the larger tongue. So patients with larger tongues, again, now we have tongue force versus lip force keeping those maxillary incisors from retroclining more than others. The patients who were more of a class two relationship, having a high baseline A and B, relates to more tooth movement, which is suggesting either we need to move retrognathic patients further forward so the amount of advancement is what's causing the problem, or the teeth have to move further before reaching equilibrium with the lower lip. Interestingly, age, the severity of the obstructive sleep apnea, and the number of remaining dentition were not associated with the magnitude of change. So occlusal changes with long-term oral appliance therapy, now, because we've got teeth in a different position, can cause renewed soft tissue complaints. Patients will complain they cheek bite, that in order to have what they consider a stable chewing position, they will end up with an edge-to-edge bite in the posterior, and end up with chronic tissue trauma from that chewing. They can get into lip biting problems. Many patients end up in an anterior edge-to-edge, something we try to avoid in both dentures and crown and bridge, because the lip loves to get into that area. And I've had patients with fibromas that occurred from chronic trauma. So can tooth movement be prevented? There's only one study that speaks to this that was done 2010 by Marie Markland and her group, where she actually took the casts given her in the technical aspect, cut the teeth off as though she were going to do Invisalign retainers and move the teeth into a different position, and set the maxillary incisors further forward on the casts and the mandibular incisors further lingually on the casts, and had a soft elastomeric appliance that was going to move the mandible forward fabricated, hoping to compensate the normal movement due to the forces of the mandibular muscles. And what she found is half the patients actually moved their teeth in the direction she had made the appliance, so that their maxillary incisors move further forward, their mandibular incisors retroclined. But it turned out that this was only effective in half of the patients, the other half, it didn't move. They got the normal changes of the maxillary incisors retroclining and the mandibular incisors flaring forward. Other appliances have been tested with little dots of acrylic placed, trying to, so you put it up against where the teeth would contact the device. Others would go in and relieve the lingual aspect of the mandibular incisors, the facial, pardon me, the facial aspect of the maxillary and the mandibular linguals, hoping to act the forces, but long-term, it turned out not to be effective. So you have to have a plan B. Can patients wear their oral appliance half the time and CPAP half the time, or use another therapy, positional training? I have patients who wear their oral appliance for the first half of the night and their CPAP the second half of the night, others who reverse it the other way. Those who wear their oral appliance the first half find that they can fall asleep with the CPAP then when they kind of groggily put it on in the middle of the night, and when they wake up in the morning, joint involvement at all. We're gonna go back and look at what happened to patient A, who in 2004 had already been in an oral appliance for 10 years, and you can see that her mandibular lower first molar was in contact with the maxillary bicuspids, a little bit unusual, but within three more years, she'd moved further forward and had gone from an incisal edge-to-edge into a full class III incisal relationship, and she was very unhappy with her resulting occlusion. This patient returned to CPAP, actually gladly, and went under two years of orthodontic therapy to try and bring her dentition back into a normal occlusion. She was never able to move the mandibular teeth fully back, but they were able to mask the class III relationship, and the patient was very pleased with her final aesthetics, but it meant being on PAP for the rest of her life. Then we go back to my patient who had open contacts, so we see from 1994, all sorts of tooth movement. He continued to use the oral appliance and was very happy. He had no complaints. His symptoms were completely relieved, and I was worried that he might have had joint changes long-term. There are two studies that look at joint changes at a three-year period, NAP, who said there were no significant changes in three years. Almeida's 2002 study that said in one year, there was some bony changes, but not really in the joint itself. So he went and he had a full series of TM scans done, and it showed his joint was absolutely normal. Everything was tooth movement. His joint is happy, he is happy, and that's the end of his story. So your take-home points from this are that you have to remember that treatment of obstructive sleep apnea is treatment of a medical disease, and side effects have to be expected. Dentists must be able to maximize the effectiveness of each oral appliance provided and minimize side effects in order to approve adherence to therapy, because without adherence to therapy, it's a useless treatment. Patient complaints, however, may not directly indicate the actual cause, and what I tried to give you here in this lecture was the ability to go back and say, well, gee, if they complain of this, maybe it's that, and help guide you into what you should look for when a patient comes in with an unclear side effect or complaint. You have to know that side effects continue throughout the course of treatment, and for patients who are looking at oral appliance therapy as a lifelong treatment, they have to know that side effects of tooth movement will increase over that lifelong treatment. At this point, we know that only 50% of patients who receive an oral appliance will be adequately treated with oral appliance, and of those, 10% will not be adherent to therapy. It's a success rate we dentists are unaccustomed to, looking at saying, well, 40% of my patients are gonna be really happy and well-treated. We're used to much closer to 90 to almost 100% success with our patients, but this is a medical disease, and we can't expect the same results that we are used to. So I wanna thank you for your attention, and hope that you've learned something that you can take back to your practice and use tomorrow.

oral appliance therapy

obstructive sleep apnea

side effects

excess salivation

occlusal alignment

pain

treatment ineffectiveness

tooth movement

adjusting the appliance

patient adherence to therapy