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For a Free Consultation with Dr. Vinograd, Call (619) 382-3884.

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In this case, what we did was the tooth was extracted before the patient got to us, and we then went in, after the fact, wanted to add a tooth in this area, add a tooth in this area.  So, what we did this time was just basically poured alginate into the underside of the partial so we could take a scalpel and carve this area in the back, add pink acrylic there, and just arbitrarily add the tooth and the pink acrylic.

Dab and dish a liquid and a powder in a paintbrush, trim an appropriate tooth so it’s the right height occlusal cervically, just arbitrarily build up and dollop up some pink acrylic there, keep putting just a little bit of monomer on the pink acrylic until it gets somewhat doughy.  When it gets pizza dough like silly putty, you can literally take the tooth and squeeze it or set it right into the partially polymerized acrylic.  Paint a little bit more monomer on it, and then you’ve converted this, added a tooth to it.  What we did to it is realigned it with the temper soft liner.

Post dam modification.  You’ve delivered a denture. The patient comes in and says, “Gee the denture doesn’t stay up very well,” or they’ve worn a denture a long time.  They come back in and you look at the record. It was one that somebody made a year ago that’s now graduated so you inherit this case that’s a year or so old, and the student that made it had graduated.  The patient says, “It doesn’t stay up very good for me.”  So, if the denture doesn’t stay up very good for a maxillary denture, the most common reason is either inadequate extension of the denture on these corners by the two [25:16] or potentially and inadequate posterior palatal seal.

So, if one is going to consider repairing this area on the denture, the very first thing I want to do is take some fluid wax, the stuff that’s called Iowa wax.  It doesn’t photograph that well. If you look closely, you’ll see that there is a skin of wax across the posterior aspect of the denture that’s shaped somewhat like a butterfly shape that we try to make for our posterior palatal seal.  So, you can see over here it comes slightly through the notch.  If I feel that the back corners are deficient, I might actually drag out the dreaded border molding compound and see if I could go ahead and develop these corners just a little bit

Now, the reason that I do that ahead of time is if the patient complains about retention of the upper denture, and I go in either with compound of wax, diagnostically, and rework this posterior area of the denture. Let’s say for the sake of argument that I do that and when I’m done, the retention doesn’t seem any better.  I’ve really done it as good as I can, and it still falls right down. Anybody think of possible reasons why a patient’s maxillary denture might have really crummy retention?

The amount of saliva, either they have no saliva or the saliva they do have is extremely serous saliva, the stuff that’s really runny, the stuff that makes the best retention for dentures is the ropy saliva that slaps you on the rubber when you’re doing prophies. You take it out, and there’s this thing that’s about that long but it won’t break. It won’t snap.  It just sort of whipping around there.

If someone’s got spit like that, then they’re probably going to do really, really good with an upper denture because that stuff is an interfacial surface tension provider. It stays in real good. If somebody’s got that really, really clear runny stuff that is just lighter fluid, those people are going to have a tougher time.  So, they might either have really the wrong kind of saliva or no saliva or are really poor anatomical shape to the maxillary ridge, really flat.  Some other people have had trouble whether they’re people with extremely round faces and really tight cheek muscles.  It feels like no matter how they move their mouth, their lips at all, their mouth, their vestibule, their cheek muscles are so tight that it lifts off a lot from the denture.

So, people with these really round faces and high, tight cheeks, if this is the depth of the vestibule and that’s the denture flange going up in the depth of the vestibule and this is out toward the cheek, that area out toward their cheek, anytime they more their lips, is flexing up and letting air over the top. With some of situations, reworking my posterior palatal seal isn’t going to do anything for me.  So, if I lay on the Iowa wax or do a little border molding or whatever and the retention doesn’t seem to improve significantly, stop.  Don’t bother to go any further because you will turn this whole thing to plastic, your retention won’t be any better if it’s good as what you started with.

So, first, if you diagnostically try it on these things, see if the moderate retention improves significantly.  The second thing you want to do is if somebody comes in, they complain about retention of the upper denture, the very first thing you do is a slap a PDS in and say we’ll just realign it and that will fix everything. So, you take a realign impression and you send it off to the lab.  You get it back. You try it in, and it’s just as crummy as it was before.

So, again, if they come in with a poor retention of an upper denture, what’s one of the first things you can do to see if you’ve got relative intimacy of contact between the denture and the tissue?  What’s something you can check with?  PIP paste, and so what I would do is put a thin, thin filling of PIP paste on the upper denture, sit it really firmly, and if I have significant unevenness in the burn through pattern, it is okay to grind down the intaglio surface of the denture where you see tons of  burn through.

Then, reapply the PIP paste and put it in, at the time you take the denture and you’re getting pretty uniform burn through pattern through the real thin layer of PIP paste you put in, surprisingly many times the retention goes up markedly, a lot. You didn’t send it off to the lab. You didn’t have to realign it.  You just made sure the inner aspect of the denture had some semblance of being able to fit.

Now, if the denture’s 20 years old, you’re probably not going to bother doing that because I’m assuming the denture’s probably going to be poor fit, but if the denture’s not that old and they’re having problems, that’s what I’m going to check.

Let’s say for the sake of argument we figure out it’s the post dam. So, we go ahead and pour a plaster index on the inside of the denture.  Once the plaster index has been poured, it captures the tissue surface, and you can see where we’ve put our Iowa wax in to give us a little more indentation for the posterior palate seal.

This is the part that freaks students: I go to the dam, and I cut the back denture off completely.  They’re like, “What did you do? Oh my god.” So, you set the thing back down on your model.  So, you’ve got your model. Now, remember your model did a very good job of capturing intimately the tissue surface of that denture looked like, and this is one of those areas.

Can you see that if I’m trying to paint this entire area across with a dab and dish of liquid, a dab and dish of powder and acrylic, when I’m painting in here, it looks fine, but when I’m trying to paint over the too glossy areas, it wants to go back in the middle?  It’s a pain in the butt and takes forever. So, this is one of those things.  This is the perfect indication for the use of that triad material. So, what you do here is on the posterior aspect where we cut it back, bevel this.  I would bevel the plastic toward the oral side away from the tissue side. I’d put bonding liquid along there.  There’s that bonding liquid back with the triad material. It comes in a brown bottle.

So, I’d put bonding liquid there and then cure that and then take a sheet of the pink triad material, cut a strip of it, and very carefully adapt it to this really well. You can do a very beautiful job of doing that, put the air barrier coating on it, put it in and cure it for 10 minutes.  Then, you’ve got a new posterior border on your denture.  Again, you wouldn’t even bother doing this if you didn’t see a marked improvement and retention when the patient came in complaining of retention and you tried to diagnostically put some fluid wax or something along the posterior aspect in the denture to see if that worked better.  If it did, you go through this procedure, and it will give you a new back end on that denture that will give you significantly better retention.

This is one where we took basically a realign of a denture. So, this is the old days where we would do immediate [33:06]. I said, “Okay, but let’s do a realign of the denture.  Then, on the inner aspect of the realign, we put the fluid wax.”  This is a kind we used to use.  It’s called proectowax.  It’s what the Iowa wax replaces, and so, we’d have that set up.  Here, again, we have the posterior palatal seal, but what is it that that thing’s supposed to do?

In any individual, when they go ahead and use the denture, you want the maxillary denture to stop at the junction of the hard and soft palates.  So, the hard and soft palate junction, we want to have a little extra bead of the denture going up in the air. Reason being, when a person sneezes, swallows, yawns, does lots of different things, this area of the soft palate where the uvula hangs can flex up. It goes up in the air.  If this area of the uvula goes up in the air, what it can allow is a little bit of air to come over to come over the top edge of the back of the denture, and that can cause the denture to break at suction.  So, the working of the posterior palatal seal is to just give us a little extra beading of that area right there so that we maintain seal if the soft palate moves.

So, if you look at the posterior aspect of the denture cross-section, here’s the tuberosity.  It goes up to the roof of the mouth. It comes down for the other tuberosity. Then, we go ahead and we build the denture that’s on this.  So, we’ve got a denture that’s built here. Here’s teeth, and then here’s our denture flange that’s supposed to fit in this area intimately.

Now, what happens when we process a denture and the denture is removed from the stone cast, turned from wax into plastic, it’s all processed.  In the lab, they break away the stone model.  What happens to the dimensions of this acrylic looked at in cross-section is it tends to shrink towards the middle just a little bit. So, areas that are out here on the outer aspect would actually pull in tighter and rub tighter. People follow that okay?

The areas that are in here where you got the inner aspect of the hollow vault going up in this area if I blow up the denture, it would tend to pull away a little bit here and here. People follow that okay? So, you’ve got this curved shape of the denture.  If it’s going to shrink a little bit to the center where it fits the roof of the mouth, if it shrinks in there it’s going to separate.  Can you also see that the deeper a person’s vault is, the more pronounced the pull away is? If a person’s maxilla was as flat as a pool table that it was just straight across, their thing shrunk to the middle. Can you see that would cause no vertical separation? If I had a really V-shaped ridge that almost looks like a submucous cleft so that there’s this incredibly deep vault going there, near vertical, when things shrink to the middle, now I’ve got more problems there.  People follow that okay?

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Dab and dish of liquid, dab and dish of powder, dip in the liquid, pick up some powder paint, paint some on.  You paint it in a little bit at a time.  Again, you want to remember that dental students forget that runs downhill so it shouldn’t be a real surprise that if you’re holding this the way the photograph is, if you’re holding it so that the teeth are vertical and you paint it so that the stuff is here, where is it going to run?  It’s going to run all over the labial surface of the teeth, right?  I would think that’s self-evident, but it’s amazing, the number of students that don’t bother to pick the thing up and hold it so that labial aspect is facing up so when you go ahead and pour the acrylic on there, it just tends to lay there.  If it’s on a curved surface, you’re a little bit frustrated because you can’t do too much of the curve all at once. You’ve got to pick up a little section and lay it on there, and you keep bathing it in liquid until it gets fairly set up, until it gets leathery.

Then, you can do the next part and do the next part and put the thing in the pressure pot.  When fill this pressure pot, you check it out at the desk. It’s got a little curly que in it.  It’s got a bicycle pump valve on the thing, and next to the model trimmer on the end of the clinics as opposed to the blue clinic is a little quick disconnect that the air hose can plug into.  So, you fill this thing about two-thirds full of hot water, put your repair in there, pump it up to 20 PSI or just under 20 PSI, and it will set up that acrylic for you so that it’s quite hard and resist stains and is stronger.

So, many times, you can’t get your entire repair done in one addition because, again, the acrylic wants to slop and run around.  So, you may go back a couple or three times to do it, put it in the pressure pot for about 3 to 5 minutes.  Then, take it out, paint some more on, put it in for 3 to 5 minutes, take it out, and you can put some repair acrylic. So, there’s your before with the crack, and there’s your repair.

What if you’ve got a fractures or a damaged tooth? One of the easiest things is when a patient comes in, and their tooth just delaminated from the denture.  It didn’t break.  They’ve got the tooth.  They’ve got the tooth, and it just came out of the denture. If that were the situation, what you would do is take your medium skinny acrylic bur and just lightly freshen the plastic in the little divot that the tooth would have left, slightly freshen the plastic on the lingual of the tooth.  The tooth will fit right back in the same spot, relieve a little bit from the lingual aspect or the palatal aspect, and you can flow repair acrylic in there. It will seal very nicely.

In this situation, the tooth itself was fractured so one hopes that somewhere in the record, and those of you that make dentures for patients, please in big, bold printing in the form 6 so that Helen Keller could see it, put the mold in the shade of the teeth that you used.  So, if the patient shows up in two years with a broken tooth like this, no problem.  We’ll just go check out an equivalent tooth from the desk, single central incisor, and we’ll go ahead and grind things out the fix it. So, we whip open the form 6 to look for the shade and mold of the tooth, and it isn’t there.  Then, you get out your shade guide and mold guide and do your best to match the tooth.

In a dental office you’re not going to have a big stock of teeth so you would just have a nice relationship with a friendly laboratory dental laboratory that was physically close to you. So, if you were practicing in Ann Harbor, an easy thing might be for you to have a relationship with Sharp Dental Lab because if the patient wants to drop this off in the morning and pick it up later in the afternoon, can you see it doesn’t work to send it to Dental Arts in Lansing for one of those quick turnaround things?

So, wherever you are, unless you’re in Gander Bay, Newfoundland or something like that, there should be a dental lab within reasonable proximity of you so you go ahead and have a relationship with the.  Send the denture over to them, and they’ll just do the repair and get it back to you.  If it’s one of those situations where if in your office you purchase some self-repair acrylic and one of these pressure pots, you can be an extreme hero to a patient if you can go ahead and set them in the spare room or have them read a magazine in the waiting room while you go ahead and do the repair with some self-repair acrylic in the office.  That can be a real practice builder, and they think you’re really a nice person because you got it back to them right away.

So, what we do here is just clean out the divot where the tooth used to be.  Now, if the tooth came out intact, you would see a recess like this on the denture.  You would just lightly freshen the acrylic with the medium skinny acrylic bur then freshen the acrylic on the inner aspect of the tooth and put the acrylic back in place.  Here, again, we shape the tooth so that the tooth fits appropriately in that.

So, stabilize the tooth in there, what happens a lot of time is it’s helpful to put a little, tiny dollop of sticky wax in this incisal corner and on this incisal corner to stabilize this tooth because when this thing’s just sitting here, it’ll fall out.  It won’t stay put that well.  So, here, again, we take our self-curing acrylic, dab and dish, stick your powder in your paintbrush, and then go ahead.  Again, what the circles are here for is you could put a little bit sticky wax on those corners just to stabilize the tooth. Dip in the liquid, pick up some powder, paint it in, cure the thing, finish it and polish it, and you’re good to go.

Here’s a tooth that’s broken on a partial denture next to a clasp area. It’s a similar kind of thing.  You can see how this was just ground out.  So, we ground out the area where the tooth sat. We got a replacement tooth, same size, shape, and color and went to ahead.

So, again, in practice you’re not going to stock a bunch of these things.  So, you can make one of these bonded repairs, but usually you’re going to better off if you have some relationship with a lab in reasonably close proximity where you could send it to the lab, and they’ll return it as quick as is possible.

So, that again just shows grinding things out, finishing it up, trying the tooth in, grind the tooth to fit, we hollow it out, we get things so that they fit, bond them back in. We’re just going to use a little sticky wax to hold it in place. So, here is our repair.  Again, back in the pressure pot, we’re going to boil the pot up to about 20 PSI.  There’s a little pressure reliever valve right here on the pressure pot so if you try to put a little more air pressure, it’ll just start hissing, and it will let the air out of the pressure pot so it can’t go too high.

So, what if we have a temporary partial or just some sort of a partial?  The patient’s going to have teeth extracted.  We know the patient’s going to have teeth extracted so they’ve had some sort of a flipper that’s being converted to a denture because they’re having their teeth out.  What one can do in that situation is if you go ahead and just take an alginate impression of the patient’s partial in place the day they come in for the surgery, this would presume that you, yourself are not doing the surgery.  If you were a private office, you train your auxiliaries how to do it.

So, can you see if you just take a nice alginate impression with the partial in place, typically, the partial will come out with the impression? What we’re going to do is take an appropriately colored repair acrylic and pour it directly right onto the impression.  So, if you just take an appropriate shade of repair acrylic and just pour the alginate out with tooth colored acrylic, but you’re only pouring the alginate out to come up to the tissue surface of the tissue side of your temporary partial. So, don’t overfill this grossly.  Just the clinical crown aspect up.

What’s going to happen is this polymethylmethacrylate will bond very nicely to the plastic that’s already there with your temporary partial.  So, can you see that if you separate this thing out, we’ll have the teeth on it, but we won’t have any labial flange on the labial aspect of that.  When we pour acrylic in just to form the teeth, the next thing to do is to go ahead.  You can just pour this impression out on either stone, whatever your pleasure is.

What we’ve done now is we poured the teeth in there.  Now, we just quickly pour the quick setting plaster model in that so when we separate the impression from the quick setting plaster model, here is our original partial, and here’s the plastic teeth that we just made from the alginate.  What we can do here now is just paint pink acrylic ink down here to create a flange on this. This is all done pretty quickly.  This doesn’t not take a long time. So, again, dab and dish of liquid, dab and dish of powder, dip, paint the acrylic on the labial aspect on that model, take it off, and trim it.

Depending on which shades of repair acrylic you have, you can get these teeth to match better than we did here.  This is a situation where we didn’t have a lot of different shades of repair acrylic, but, again what was this for?  To take a plastic transitional partial denture and convert it to a full denture with the extraction of the few remaining teeth.

Reviewing what we did.  We took an alginate impression.  We first poured the teeth in the alginate and this tooth-colored acrylic then put the plaster model on the inside of it and paint it on labial or buccal flanges to give us flange on the denture.  We polish and smooth those, and it can flipper. There were a few teeth that were remaining.  They didn’t respond well to perio treatment. They decided they were going to take the teeth out, alginate impression.  Just pour acrylic directly onto the impressions of the teeth, pour a model, and go ahead.  Here’s your plastic tooth that’s bonded on to this pink plastic.  Here’s another one.  We can just paint a flange on the outside of this in our model. So, we paint the flange on, and we have potentially converted this flipped to a denture without too much drama for the whole thing.

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Welcome to the University of Michigan Dentistry Podcast Series, promoting oral health care worldwide.

So, what do we want to look at today in terms of repairs?  What do we do if we have a fractured denture?  Has anybody had a broken denture in half that they’ve had to deal with before?  So, it will be review for some of you. A fractured or a damaged tooth.  We’ll also go through modification of a temporary partial denture or partial, post dam modification, and clasp repair.

So, if we looked at a fractured denture first, the way you usually repair these things is either with polymethylmethacrylate, a self-curing acrylic, or we can use the pink colored triad material.  Here’s a little example where there was a little bit of a flange broken off the denture, but it would exactly be the same procedure if the denture were broken in half right down the middle. So, the fact that, in this case, there’s a corner broken off it, the technique is exactly the same as if it’s broken right down the middle.

Now, sometimes what makes this process more difficult, we just had one in our clinic last week, when polymethylmethacrylate breaks and a patient brings it in, the two pieces were the fracture plane is an extremely crisp and clean fracture plane.  So, when you put the two pieces back together, there’s really no question whatsoever about how they fit because the two pieces will mate very perfectly.  There’s one exception.  Anybody have any idea what the exception is?

The patients will, oftentimes, try to repair their own denture with a glob of superglue, and if patients put a big glob of superglue on these mating surfaces, superglue will actually melt the plastic a little bit. With patients, they’re just like dental students.  If a little is good, a lot must be better, and a whole lot must be a whole lot better.  Not true.

So, then, what happens is the patient comes in and these two pieces that would originally have mated together very nicely no longer fit, and sometimes you have to go to plan B, C, or D.  The hope is when patients come in, it’s been broken, they haven’t tried to fix it with superglue, and if you take literally one drop of the real runny superglue, put it on one of the mating surfaces and hold just the two pieces together for about 10 seconds, it will weld them together.  That’s not your repair.  That’s not your repair.

The only reason you stick things together and the thing I hope will show for this particular example is doing some sticky wax.  So, that’s why one person is holding it together real carefully, and someone you trust not to drop the sticky wax on your finger or thumb drops some sticky wax on.  You can accomplish this same thing with one drop of superglue on the fracture plane and go ahead and tack it together.

So, now that the two pieces where the fracture has occurred are tacked together, what we want to do is pour some sort of an index on the inner aspect of the denture.  So, what we do in this particular case because it happens to be a quick setting plaster index. Up the clinic, the stuff that you folks would have would be mounting plaster.  So, if you make a creamy mix of mounting plaster and put on the inside of the denture, it will basically make an index so that those two pieces of plastic, when they’re fractured apart again intentionally to do your repair can be repositioned so they’re in the correct orientation.

Now, the indices that we make may be made out of plaster.  They may also be made out of PVS, and they may also be made out of alginate. You’ll see examples of both of those later on.  So, here we have the index made, and, again, whatever the index material is inside your fractured denture, like I say it happens to be quickset plaster, it could be PVS injected on the inside. I’ll usually use medium or heavy body so you get a rubber model.  It’s an expensive model, but depending on the situation, it can be worth it.  You can also use alginate.

So, now that we’ve got the index made, then if we clean off our sticky wax, if this thing had one drop of superglue in this wax, you can tax the denture off and intentionally break these two pieces apart again. So, here, you’ve got your two pieces.  The repair is not done, but they now fit on an index.

So, what we then do is bevel the oral the surface.  That is, bevel this fracture so that when we put the repair acrylic in here, it has a broader area of contact.  So, if you look at this thing on the side, you’ll see how on the tissuemost aspect of the fracture, we didn’t cut it apart a lot, but we beveled both sides back on the side that faces the tissue.  There’s a little bit of opening here, not a problem because the index we poured on the inside of the denture captured the shape of the tissue surface in this.

So, we bevel this back for two reason.  One is it freshens the acrylic because when the acrylic has been in contact with spit, some of spit microscopically soaks into the surface of the plastic and contaminates the plastic.  So, if you put fresh repair acrylic on that contaminated surface, it doesn’t bond as tenaciously as it does if you cut that surface back a little bit, exposing fresh polymethylmethacrylate that’s never seen spit.  So, when you go to put your repair medium on there, it tends to stick better. It bonds better. Then, the reason that you bevel back from the fracture line is, can you see, you have a larger surface area for your repair material to grab onto.

What we do in this case is if we’ve got some self-repair acrylic, and this stuff is available at the dispensing desk.  It’s a self-cuing pink repair acrylic.  So, it’s the usual thing, a dab and dish of liquid, a dab and dish of powder if you’ve got the plastic dab and dish liquid and powder.  Moisten the fractured surfaces with some monomer on a Q-tip.  I tend to like these sable brushes with the black, wooden handles as opposed to the little throw away nylon brushes they want to try to give you because the nylon brushes aren’t nearly as good for picking up small increments of repair acrylic.

One can also the repair with the triad material.  I don’t like the triad material as well because it bonds pretty well, but I think the triad material, being a composite, is quite brittle.  So, for those of you that have made trays or record bases from triad, you’re aware that you drop them on the floor, they tend to shatter.  So, I think in function, the polymethylmethacrylate repair, in my experience, is a little tougher.  It tends to hold up better and not refracture.  This is particularly the case for maxillary denture, for example, when it fractures down the midline, and we see that fairly commonly.

So, in this situation, we would have freshened, cut back the surfaces with a little bit of monomer.  We put some bonding liquid on the fracture and, then, take some of the pink repair triad and press it under nicely.  What we’re doing up here is having a little dab and dish of just regular acrylic monomer.  What works well for that is if you dip in a little instrument to just smooth this material out.  It doesn’t increase the bonding.  It’s just a handy lubricant to smooth that material out.

Then, you put you air barrier coating.  This stuff, again, prevents oxygen from coming in contact with the surface of the triad as it’s curing so that when it’s fully cured, this air barrier coating, the large jug of material back there that’s a big jug of clear liquid snot, it’s not the Vaseline.  Question.

The particular triad, there isn’t.  So, if you have a dark characterized denture for an African American patient or another patient, the triad itself that we have doesn’t come in different colors, but if you would take the powder liquid, the polymethylmetharylate, if we know we’ve got a repair coming in, if we call Ward Dental Lab or Sharp Dental Lab, they have some shaded or toned repair acrylics that we don’t carry here.

The acrylics we’ve got in stock here is just your standard light fibered pink, and if you need a darker shade, it’s not that it doesn’t exist.  We don’t typically stock it, but when we’ve needed it in the past, if we just call the lab where the denture’s made, if we call Ward or Sharp, “Could you send us some of your characterized repair acrylic?”  They send us a little bit of the powder, and the powders work with any of the liquids.  So, the fact that we don’t need to get any special liquid, our liquid works just fine with the powder.  So, if you’ve got one coming up that you know is a shaded acrylic, then just call the lab and get some of equivalent shade in a self-curing acrylic.  Yup.

Air barrier coating’s on.  It goes in the triad ovens.  The powder comes and you shade it. We shape it back with an acrylic bur.  We pumice it, and so what we’ve got here is the repair once it’s completed.  It’s pretty much undetectable from the original.

A question was brought up, and it’s a very salient question if your patient has a characterized or anything other than light fiber pink plastic bases on their dentures.  The stuff we normally stock at the desk doesn’t match.  So, if you know you’ve got one of these coming in or if you’ve seen it, then, go ahead and get a hold of Ward or Sharp, and they’ll send us a small amount of the shaded repair acrylic to do the repair.

So, what if we’ve got a patient that fractures maxillary denture, but it’s not broken in half?  The patient basically is fractured here and goes across here. So, we’re going to do the same thing.  Some people say, “What if I just pour a little acrylic right on that fracture line? Won’t capillary action suck the acrylic into that crack and heal the space.”  Short answer:  No. You don’t get enough bonding on that.  It refractures again about the time they get to the parking structure.

So, if I’m going to go ahead and cut a little channel along this because isn’t broken in two halves.  Again, I want some sort of a matrix so when pour the acrylic in there to do the repair, it’s not running all over the inside of the denture, and that’s where we go ahead and inject medium body PVS or heavy body PVS in the inside of the denture.  The beauty of using some sort of a rubbery material is you don’t have to block out any undercuts. You just squirt it everywhere, no blockouts.  Let it set up, and it comes in and out of the denture just fine.  So, medium body PVS is just fine for that.

So, you can see we’ve made that little index, and when we take the denture, we pull this from the inside of the denture.  This is what the labial aspect looks like.  So, this represents the inner aspect of the labial portion of the denture.  So, what we do now is go ahead and take a small acrylic bur and go ahead and cut that plastic out of there completely, beveling it toward the tissue surface.

You put your index back in. So, this now captures what the inner aspect of the denture looked like, and then, again, a dab and dish of liquid, a dab and dish of power, dip in the liquid, pick up some powder, and just paint these areas in.  Again, if we get some from the dental laboratory, we don’t have these ate the desk anymore.  The companies do make kits if you have this in your office. They give you different shades of self-repairing acrylic with a common bottle of liquid.  So, what we typically do is use self-curing acrylic.

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Now, many times, depending on where this has extruded to, it’s way above where the reasonable plane of occlusion ought to be so I’m smoking that puppy down just like you would if you were going to adjust the wax rim on a denture. So, the denture stuff really does come back to help you even when you’ve got teeth there. Look at your landmarks.

So, the reason one might consider making a partial like this is this side of the mouth is extruded. The mouth, perhaps, was endodontically treated.  So, we cut this puppy right down even below the height of the gums at the distal marginal ridge.  We smoke that, too, and then I put a bevel around this whole.  Then, all I have to do is hog out the whole pulp chamber so when I get this coping back, this post and coping, it looks like a mushroom with this mushroom stem coming down the center of it. It sort of goes down to where the pulp chamber was.  People following me okay?

The occlusal is just a flat occlusal that doesn’t try to go much higher than the gums. It just covers the occlusal of the tooth, and it goes down to the bevel that I created out of it.  Now, I’ve got this thing that’s about the height or a little below the height of an ideal plane of occlusion.  Then, I can take my partial and just rest it over the top of it.  I have no intention of putting a tooth on top of this.  My teeth are going to be above this, but my plane of occlusion will now be even and level. It won’t be going way the heck uphill on the side where the toot was extruded.

So, look at some of those things when you’re thinking about these.  So, here’s a class III all tooth-supported with an anterior modification space.  Here’s another class III in a maxillary case. So, you basically got teeth over here.  You can see it come across the palate. Sometimes you refer to these things as a closed palate or a toilet seat for obvious reasons.

So, you can go ahead and not cover too much of the palate, but the thing here is if you look at this and say, “Why wouldn’t I just choose to use to do that longer span?”  We’d have three [40:27].  Can anybody give me some reason why I might not choose to do that as a fixed partial denture? Why wouldn’t do it like a bridge?  Do people feel comfortable about that length of span?  It’s getting pretty long.

Now, you’re going ahead and putting a crown on a cuspid and you’re putting a crown on a molar. Again, the thing that you remember is that way back in the depths and the recesses of your brain in Dr. May’s lecture, something called Ante’s Law. Anybody vaguely remember what Ante’s Law talked about? Number of square millimeters of root surface in contact with bone.  I’m not talking about anatomical root surface. I’m talking about clinical root surface.

So, if a person has lost some attachment and they’ve lost some bone height, can you see that they’ve still got the same anatomical root surface, but they don’t have the same clinical root surface?  You people follow the difference between those two?  So, suddenly if you lose bone, your clinical crown gets taller, and your clinical root gets shorter.  So, you’re starting to look at how many square millimeters of tooth do I have here, and how many millimeters of root tooth do I have here in bone.  Is that equal to or greater than, preferably greater than, the square root of all the teeth that are being replaced?

Now, the other thing that happens when you have a longer span bridge in the upper or the lower jaw.  What do you suppose one of the forces that happens on a fixed partial denture here is that just really beats the periodentin up a lot?  It’s not straight down vertical forces.  It’s buccal lingual forces, forces that try to rack this thing buccal-lingually, and can you see that if you do this with a partial denture, this is what we talk about when we talk about cross-arch stabilization?

So, the fact that the arch comes over here and gets a good grip on this tooth on the other side of the arch, can you see this is now like a three-legged milk stool? It’s pretty stable so if any forces try to take this and wiggle it buccal-lingually, it gets braced off this.  So, longer span from front to back is not always ideally treated as as fixed partial denture.  If you can put implants in there, not a problem, but long span with a fixed partial denture can spell heartache especially if you ever get a long span in this anterior tooth. I see it over and over again, a cuspid that has been endodontically treated and has a post end corum in it.

So, I can’t tell you, over the years, how many of these long span fixed partial dentures I’ve seen in which the anterior abutment is a cuspid that was endodontically treated that had a nice cusp gold post end corum and a really nice PF fitting crown. What do you suppose I see happen to these teeth three to ten years down the road?  Vertical root fracture.  Now, we are in the vernacular, screwed because now I no longer have a cuspid to hold on to.  I’m up to a lateral incisor. A lot of support there, isn’t it?  That’s a really peach.

Now, it’s even a longer span bridge using a lateral as our primary abutment. Doi. Well, because the lateral’s not too good, let’s just pull the lateral and let’s splint the two centrals together. Now, you’re just getting insane.  Don’t even come to me with that.  Now, you’re thinking really hard about implants.  You’re thinking really hard about some sort of a partial. So, longer spans are not always the best treated with fixed partial dentures because of the buccal-lingual force that will go on those longer span bridges, and the partial can give us cross-arch stabilization.  So, it really helps mitigate the buccal-lingal forces on those teeth.

So, basically, here’s just another example of a class III tooth-supported all the way around.  Again, we try to keep getting these things done. I ‘m much happier if they’re tucked around the distal, labial, or the distal-labial corner.

Then, we get to the class IVs.  Class IVs are always tough because your replacement teeth area always in front, and sometimes, these tend to be tippy and really hard to get the tippiness out of these. So, over your practicing lives, what you may want to consider is a lot of these class IV partial denture cases can really be treated successfully if you can find one spot somewhere under this anterior area to put a single implant, and the advantage of doing it with a partial denture is the location of the implant doesn’t have to line up exactly with the tooth.

Now, if you’re in practice for a very long time, what you’re going to see is some genius with no planning put some implants in the anterior area, and the location of the implant is exactly in the interproximal embrasure area of where the tooth ought to be. So, now how do you get that so it looks pretty when you’re trying to put fixed work on it?  So, on these, if you’re doing it with a partial denture, you can just put a single implant anywhere across here, and it’s going to work really well.

Very seldom to show you this one.  It doesn’t happen often.  If you have one of these people that’s got class III lower arch.  It’s seems like all the teeth toe in lingually. When you survey, you can fit anything on the lingual of the teeth. Not very often, but, occasionally, we will do a labial bar.  So, all the teeth are fitting so far in lingually, we can’t fit anything bilingually.  So, the partial goes out here, and as luck would have it with most of these cases, bone lip conceals that pretty well.  Most of the time now, would we just choose to do that as an implant? Absolutely, you would choose do it as an implant.  On these big cases, the more teeth you’re replacing up here, the more difficult it is not to have that anterior tipping phenomenon.

In your practicing lives, unlike mine, one of the things I try to tell anybody with this situation is to try to get an implant somewhere in here somewhere to brace the anterior aspect of this.  Many times with class IVs when they come back for recalls, this is what you see because of that tippiness.  You can beat yourself up about this, but you can’t always get rid of this try as you might.

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So, this is your fulcrum line if it’s occlusal word forces. If it’s sticky forces trying to remove the partial and the retentive fulcrum line, it goes from the tip of the clasp to the tip of the clasp. So, that would be the removal fulcrum line.

Class II upper, same kind of a thing. You’ve got a unilateral distal extension.  We basically, up here, got our primary retainer, our primary retainer, indirect retainer.  Third point of reference.  Here, again, they happen to put a T-bar clasp on this.  What I would do a lot of times, if I could take a high speed hand piece or carburetor and disk, if I had a reasonable retentive contour at this distal labial aspect, I’d try to recontour this and cut this part off.  Again, the curvature of this infrabulge and aspect, if I can get that to come down a little bit distal to the point of greatest convexity, I hide the whole thing better.

Now, with a lot of these patients, when you’re assessing the patient and you’re thinking about what you might be doing for clasp design on any of these patients, male and female, when they’re in and you take your preliminary impressions, one of the things to do with the patient is just get them so they moisten their lips.  Their lips are nice and relaxed, you ask them to smile.  Then, you ask them to put a really fake smile on that’s so hard it’s going to break their face, and see how high they can really fake smile.

You may get some people that even on the fake smile, they’re lip doesn’t get up far enough so that’s an issue, but that’s useful information.  That’s useful information because if a person has a really high smile line, then you want to do anything you can to try to hide or diminish how obvious the clasp is.  To that end, it’s going to be better if you survey these things and be looking real hard for retention at the distal labial aspect of the tooth. Hope that you do not sea frenulum attachment coming in there or a big soft tissue undercut.

Soft tissue undercuts bother me more than frenulum attachments.  If aesthetics is a big deal, the patient can’t afford a precision attachment of some sort and I’ve got a frenulum in there, what do you supposed I want to do?  I’m going to call my friendly neighborhood periodontist or if you do it yourself, I’m going to do a frenectomy.  I’m just going to cut it away so I can put my clasp where it will be aesthetically the most pleasing, and I’ll just lose the frenulum at that point. If there’s a huge soft tissue undercut, that’s a little more difficult to deal with, but if it’s a frenulum that’s in the way, you can consider doing a frenectomy to maximize the aesthetics of your clasp.

Okay, with class II we’ve got a modification space, a front or a back modification space.  So, here’s your clue:  Class II unilateral distal extension, and there’s another spot that’s edential.  So, here, we’re bounded by teeth so we have a distal abutment here. So, this would be a class IIP.  Here is basically the framework of that, which basically shows you the posterior modification space.  There’s the posterior modification space when we’re getting ready to take a bite out of it. Same kind of a thing in the mouth.  Okay, here’s our class II, posterior modification space with the molar.  Primary occlusal unit.  Our primary occlusal retentive unit.

Another one here, primary retainer. That’s the word I’m grasping for, retainer, which includes an occlusal clasp, a retentive arm, and a reciprocal component. Either that’s going to be a lingual reciprocal arm, or it’s going to be a lingual plate that goes across the lingual of the tooth.  So, we have occlusal rest, clasp component, and reciprocation component.  Okay?

So, you can also have a class II. Here’s your distal extension free end, and then we’ve got both and anterior and posterior modification space on this.  So, again, it’s still a class II. It happens to have two modification spaces.  So, here’s that case in the mouth, combination case. You’ve got a, upper denture.  You’ve got your lower partial. You’ve got your free end side with the clasp.  We’ve got some modification spaces, and then, over on the other side.

Here’s the same thing in a maxillary case.  Again, here, we’ve tried to make use.  These were done several years ago when we took these pictures, and, over time, what we’ve tried to do with these eyebars is I tend to like a modified T-bar rather than an eyebar.  The reason I like a modified T-bar rather than an eyebar is it just has a bigger footprint.  It touches more tooth than this, and, again, if I can try to hide this around the back corner of the tooth, I don’t think I’d pay an aesthetic price for that.

One of our former faculty loved doing these.  He would try to make this like jewelry.  So, they were really fine, barely showed up at all.  What do you suppose the downside of that was? They didn’t necessarily break. They just came out of retention real quick so you didn’t have a big enough footprint, and this arm that came down just wasn’t stiff enough that they were back all the time getting it adjust which, over time, led to what one individual said as they’d break.

So, if I’ve got a slightly more robust arm here and it doesn’t have to be a truck bumper on a Kenworth semi going down the road.  It doesn’t have to be big, but I find that the little foot going towards the distal just gives me more square millimeters of contact with the tooth than that little area of the eyebar well, but, again, I try not to have this thing come down mid-labial on the tooth. I want it to come down on the distal labial aspect because it’s going to give me a more aesthetic partial, and depending on the patient’s smile line, they just don’t show up that much. It works out really well.

Class III. This pertains to one of the questions asked earlier.  If I’ve got a class III, hypothetically I shouldn’t have to deal very much with the resorption of the edentulous ridges.  So, if I’ve got an area in here or an area in here, when you get to the mouth, both of these area where they’re edentulous are bounded by teeth. So, when this person bites down really hard on their partial, they’re not squashing their gums because the partial is too supported all the way around.

So, if this was delivered last year and you wind up getting the patient 11 or 12 months after this was delivered and they’re telling you it doesn’t fit, again, what you can go on is what’s written in form 6.  Form 6 says everything fit just peachy at the time it was delivered, and the occlusion was good. It doesn’t fit so good now.  My first supposition is the patient either hasn’t been compliant wearing it or it got dropped.  It got dropped. In either case, what’s going to happen is if the framework gets sprung, you can try to fiddle and fix it, but it’s not going to work well.  If the partial is not being worn as was asked before, this distal molar and this distal molar, it’s very likely that they may in fact be pounded a little more mesially.

So, that distance from the mesial marginal ridge of this tooth to the distal proximal of this tooth will have decrease a little bit, and if you try to decrease the partial a little bit, it will seem really, really, tight because what’s happening is your partial denture’s not acting like an orthodontic appliance. You’re trying to see if you can get those distal teeth pushed upright again.  So, depending on how long the patient was noncompliant about wearing it, you may or may not be able to get that much movement.  You may or may not.

Now, here’s another one.  Now, many times people will ask. If I’ve got a class III partial that’s completely tooth-supported, it’s very common that I will tend to use just a metal base with a bead retention because, again, if I’ve got a completely tooth-supported partial, I don’t plan on having to realign the underside of that partial because I don’t expect the gums are going to change much because I’m not putting so much pressure on them.  I’m not putting any pressure. So, what I’m doing basically is a completely tooth-supported partial, pretty common that in the edentulous areas, I’m just going to put a case metal base with bead retention.

Occasionally, we’ve done this if I’ve got a tooth in this area.  So, here’s a partial that’s completely tooth-supported, but were laying right over the tooth of this tooth. You may or may not be able to see very well.  Sometimes what happened with these teeth is the tooth is basically cut off at the gum line, and occasionally, these will have a post-encoating put on them.

Now, can anybody imagine a reason why I might have my partial denture just go over the top of that tooth?  Any thoughts?  Sometimes if you take study models and mount these cases, the tooth in this area sits way up above the point of occlusion. It’s almost in contact with the upper gums, and when you look at it, it’s really obvious from the front that this tooth in the back because it was unopposed for some period of time, extruded.

So, if you’re going to leave that tooth at the height it showed up, your plane of occlusion on that side of the patient would be going way the heck up in the air where you’ve got no room to work on the upper arch.  So, one of the things you want to do with study models is evaluate the orientation of your plane of occlusion. In other areas, where do you suppose you’ll learn how to evaluate the orientation of the plane of occlusion?  Where do you learn that?  With your denture patients.  Yeah?

So, what’s a reasonable plane of occlusion?  Even with the anterior to the center of the retromolar pad that you do with the denture.  So, what happens to students all the time when they get these bigger cases is if there’s teeth there, no matter how screwed up or crooked the teeth are with the anatomic landmarks, somehow you people thing the teeth came off Mt. Sinai with Moses or something.  Oh my god, they can’t be touched. How can we possibly work with it Dr. Shotwell?

Well, where are your anatomic landmarks?  So, maybe on a tooth like this, in some cases, maybe it was already endodontically treated, and I’m not even thinking about putting a crown on it.  I’m going hose that puppy right off at the gum line, and many times, how many of you have had it?  You’ll get a tooth that’s the terminal tooth in the lower arch, the very last tooth in the lower arch? What do you often see concerning the gums at the distal marginal ridge of the last tooth in the lower arch? Gums are right up even with the marginal ridge tooth.  Anybody had one of those? They’re fun to do crowns on aren’t they?

It’s really easy to get that nice axial wall on the distal.  You people are freaking out when I say, “Give me the anesthetic”  “But they’re really profoundly numb Dr. Shotwell. I gave them an inferior alveolar.” I know they are. Now, give me the anesthetic.  Then, I go ahead, and I infiltrate the daylights out of this tissue right here until it turns as white as my lab coat because what am I about to do?  Rotary gingitize. Okay, we’re going to vaporize it because I’ve got to get a hold of that tooth.

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So, when you get gray hair and you say the same thing, they just don’t fight back as much or push back as much, but sometimes, also, it’s like the DNA on the dress.  You sort of deny, deny up until there’s any controversial proof to the contrary.  So, if you ask the person, “Where you wearing this?” “Yeah, yeah. Of course.” We don’t have the DNA on the dress, so to speak, to make the people change their story, but that’s another matter.

So, if we look at a class I partial here, basically, what’s a fairly common circumstance of a class I partial.  You’ve got a bilateral distal extension. You’ve got primary retainers.  In this case bicuspids. This happens to be a lingual bond on a lingual plate so we have an indirect retainer here.  Again, if we imagine our primary fulcrum line here, we imagine sticky foods, a Milk Dud or a Juju beans or a gummy bear sticking here trying to lift this away from the tissue, the fulcrum line’s going to be through the clasp tips, and by the fact of this touching the indirect retainer or if I have lingual plate and the lingual plate touches the lingual part of the anterior teeth, that’s going to resist the back end of this thing tipping up in the air.  More important than that because if anybody eats gummy bears, they’re coming out of their map in their lap anyway.  They don’t stay in that tight.

The biggest reason and the biggest advantage of having indirect retainers is having an indexing position for the partial to determine whether it needs a realign.  Then, if you say it doesn’t need a realign, how are we going to do the realign on the partial? Unlike a complete denture, for a partial denture what you are not going to do is you’re not going to load up the underside of these bases with a little bit of PVS, seat it in the mouth, and just tell the patient to bite together.  You’re not going to do that.  How come?

Can you see that overtime if the partial denture base saddled down a little bit because it lost tissue support, it’s very possible that the opposing teeth, if they were natural teeth extruded a little bit.  So, if you just let them bite down, they’ll just tilt it to the same orientation it had.  So, if you go ahead and put your PVS in the underside of the bases, seat the partial denture framework in and carefully hold firmly the partial denture framework so that the primary occlusal rests are down and the indirect retainer’s down. If it’s a lingual plate, you hold it so that you’re sure that that lingual plate fits down and in the teeth.

So, you’re holding the framework in its proper orientation to the teeth which is essentially just suspending the free end of partial and space over the top of the gums, and your impression material is making up the difference, rethreading the tire.  People get that okay?

You send it off to the lab. The lab realigns it.  So, now it’s come back, it’s got a new plastic underneath it.  You fit it in the patient’s mouth. You ask him to bite down.  What do you expect to see concerning the occlusion?  It’s too high in the back.  So, then you just adjust the occlusion on the partial as necessary to get it so that now the partial doesn’t rock front to back.

The bite’s even, but we may have adjusted the occlusion on the partial a little bit because if, in fact, the distal aspect of the partial sank down because of lost of support where the tissue changed, it’s reasonable to assume that the occlusion of the opposing arch followed it down which is why you just don’t have the patient “bite together” when you’re realigning a partial.  You orient the framework correctly to the teeth, and that’s where the indirect retainers come in as a really good third point of reference for situating the framework on the teeth and knowing it’s well- seated. It’s also a great device for telling whether the partial denture is rocking. Has it lost base support?  You just wait and see does it teeter-totter?

So, here’s an upper case.  Now, you don’t see that much tissue to change overtime with maxillary partials.  They’ve got a lot more real estate to cover.  There’s a lot more square millimeters of gums to support them. This whole area across the palate is pretty good support so I don’t see the need to realign maxillary partials anywhere near anywhere the rate at which we need to realign mandibular partials because we’ve got a lot more tissue support for maxillary parts.

Here’s one. Basically, you’ve got indirect retainer.  You’ve got your lingual bar, and you’ve got your clasps.  So, you check things out and see do things rock?  Here’s a lower one.  We’ve got canine abutments. On this particular case, can you see straight down, looking on the canines, that we’ve done crowns on them both and we’ve created raised singular on the two crowns?  Again, on the lingual of the cuspid as it normally exists is just that slope that goes all the way to the ground.  There’s not a good vertical resting spot.

So, if the tooth, otherwise, does not need a crown, you can build that lingual aspect up with composite to create a ledge on the lingual of it and composite. You can also go to the thickest portion of the canine, the very thickest portion down on the singulum. Take a parallel-sided, flat-ended [19:10] and cut a small ledge, a fairly narrow ledge, or you can build it up with composite.  Any of the three.

My main goal isn’t to leave immediately to doing crowns on teeth if they don’t otherwise need a crown other than for creating a resting spot.  You can do that other ways.

Sometimes when canines are rotated, we’ll put a small little notch on the incisal edge of the canine so that this framework fits on that little notch. Canines are rotated a bit.  That does not wind up being aesthetically unpleasing. Now, many times we would not use incisal hooks if we thought this was going to show very much. Rather than use this, my own prejudice would be if I could to try to use a little bit of a ledge down under the singulum at the lingual.

When we look at canine abutments on the maxilla, as much as I possibly can, what I try to do in the maxillary arch is avoid this if I can because one of the biggest complaints patients are going to have about removal partial dentures in general are actually two things.  One, they come in and out. Can you give me anything that’s fixed that doesn’t come in and out?  Well, depending on the number and distribution of teeth, you may not have that choice.  So, one big complaint is they come in and out.

The second biggest complaint is they’re ugly.  “I don’t like that big clasp showing on my tooth,” which is why anytime you get a maxillary partial denture n which you’re going to have a canine as an abutment, try to survey it in such a way if this is the canine and this is the front of the mouth here, try to work things in such a way that you see if you can come down with and infrabulge clasp arching towards the distal. So, this is the greatest convexity of the tooth.

If you look at this from the inside of the ledge, cuspid teeth or canine teeth, when you look at them from the incisal have two faces.  There’s a distal face and a mesial face, and it sort of comes around like this.  If this was the front of the mouth, anything you can get from here back tends to hide so the cheek is hiding it a little bit. If you can create an infrabulge clasp with a modified tier and eye at the distal labial aspect of the tooth, as close to the gums as you can get it, again, when you’re surveying these casts, the whole idea about trying to reshape the labial aspect of the tooth to get the height of contour as low as you can toward the gums.

I’d like my 10000th of an inch undercut to happen ideally about 0.5 millimeters from the gums because can you see, the closer you get your clasp to the gums, two things happen.  One is it’s better mechanically because you’re grabbing closer to where the tooth comes out of the bone.

Secondarily, it’s just nicer looking aesthetically because on an upper case if the clasp was way up towards the gum, depending on where the patient smiles, their lip doesn’t come up above the clasp.  So, you don’t see it, and if you’re hiding it around the distal labial of the tooth, you don’t see it.

So, over the years, I just see lots and lots of partials on maxillary cases where there is a canine involved that is far as I’m concerned are just butt ugly because somebody didn’t take the time to take a study model and survey the darn thing and see where is the height of contour. Can I come up with a survey that will give me a height of contour that tries to be at the distal labial?  Then, I try to get a good enough impression so that I hope I don’t have a lot of undercut of soft tissues to contend with deeper on the vestibule where I want to come down on the tooth because if I’ve got real severe undercut up in the soft tissue in that area, then it’s difficult to do an infrabulge clasp.

On maxillary partials, wherever there’s cuspid involved, I really like to do an infrabulge claps if I can at all, and that’s what’s drawn here. The thing I would change on the drawing is that I would not take it to the mid-labial. I would take it to the distal labial, sneaking it in around this back corner. Now, if I do that, one of the other principles I’ve got to do is I’ve to grab around that tooth more than 180 degrees so the tooth doesn’t move overtime away from the partial denture framework.

So, that means I need to get some aspect of my framework as far up as that mesiolingual, as far up there as I possibly can.  So, if my clasping is at the distal labial, I need to get my indirect retention or my occlusal retention or something as far around the corner, around the mesiolingual as I can so that I get 180 degrees of encirclement of the tooth so it doesn’t move overtime.

So, here’s some other cases where we’ll do this.  This is starting to get to the right idea, but this is sort of if we carry it over to the mesiolingual corner and then went back. It’s the right idea, but it’s like screwed that one up a little bit because if we were doing this anyway, why didn’t we just come down, arc up a little further, and have the anterior-most aspect of that T-bar be just about mid-labial on the cuspid or a little bit distal than the mid-labial.  So, my clasp engaging was right here because this, when the patient smiles, just jumps out at you.  It’s sort of like this chrome hubcap looking at you when they drive by.  Pretty, who did that for you?  Dr. Shotwell. If you have a modification space, same thing here.  You’ve got your class I because it’s a bilateral distal extension happens to have an interior modification space.

Class II is a unilateral free end, upper or lower.  So, what do we got here? Basically, you’ve got your primary occlusal rest, your indirect retainer. Your fulcrum wire runs through the retainer if we’re talking about the fulcrum line that is concerned with tissueward movement. If you bite down on food in this area and you try to push this down, your fulcrum line runs across these occlusal rest.  Your retentive fulcrum line if sticky foods are trying to lift the partial away from the tissue is going to go to the retentive tips of this clasp and this clasp.

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see the video:

Welcome to the University of Michigan Dentistry Podcast Series, promoting oral care worldwide.

So, what we want to look at today are design considerations for the various types of partial dentures.  So, we run through the class I, class II, class III, and class IV partials.  When we look at class I partials, generally, whether we look at premolar abutments or there may be canine abutments in either arch. Sometimes, we might have a premolar, a canine, or a lateral incisor, very rarely to have lateral incisor as an abutment.

So, if you look at different type so fulcrum lines again in your text, page 96 talks about different fulcrum lines. Rather than bore you and go over all that, what you want to look at is there’s going to be a fulcrum line axis for tissue-directed forces meaning when people bite down on hard foods, and if we have a free ended distal extension partial, we expect the distal extended portion of the partial to be compressed towards the tissue a little bit.  Again, the tissue is more compressible than the teeth are in intrudable.  So, if you think of biting down on a tooth and a tooth socket has got a periodontal ligament suspending, it literally intrudes in its socket a little bit.

So, if you’ve got a class I partial that has a bilateral distention and you’ve got bicuspid abutment, when you bite down on the partial, the bicuspid abutments intrude a little, and the soft tissue that supports the distal extension bases of the partial also squashes down. So, the compressibility of the tissue in several factors many magnitudes more than the intrudability of the teeth into their socket which results in a distal tipping a little bit of the partial.  So, that’s your fulcrum line or your primary access on tissue word directed forces.

There’s also another fulcrum line.  That’s the retentive fulcrum line meaning if you eat sticky foods, when you open your mouth and something’s sticking to the distal extension aspect of the partial trying to pull the partial denture away from the tissues. There’s also a fulcrum line for that, and that fulcrum line is typically going to pass through the retentive tips of the clasps.

So, if you have a clasp on either side of the arch and the object or the partial part of that partial denture that’s going to resist movement that would try to lift it out of the mouth are the clasps. Where is the retentive aspect of the clasp? It’s at the terminal third where they’re the most retentive and they go into the undercut.  So, a line passing through the terminal third of the clasp tips would be the fulcrum line on a force going away from the tissue.

So, you’ve got a couple of different fulcrum lines, not just the one going toward the tissue but another fulcrum line for forces trying to take the partial away from the tissue.  This is gone over extremely thoroughly on the chart on page 96.

Indirect retention.  What happens with indirect retention is when you have a partial denture framework, the finished partial denture that’s trying to be taken away from the tissue, you’ve got your primary fulcrum line for retention, and the indirect retainer helps brace the base. Now, the biggest purpose for a third point of reference or indirect retention on distal extension partials comes in to play when we are doing realigns of the partials.

So, if you have a patient in for a periodic recall, how many people have had a patient in for just a checkup?  You’re doing a prophy on them, and you’re going to go ahead and check them up.  They’ve got either a combination case that’s either a denture versus a partial denture, or they’ve got a partial denture in one or both arches. So, how many people have had patients like that in just to do a follow-up? Three of you?  A third of you?

The point is what do you look at when we say evaluate their partial? So, how do you evaluate partial? How is it doing?  Okay, good.  Did you evaluate a partial?  How did you do that?  “I asked Mrs. McGillicuty if it was doing okay”. What did she say? “She said it was fine.” Did you do anything else? So, one of the things that one would do in a distal extension partial is how would you determine whether or not a distal extension partial might benefit from a realign.

One of the things is PIP. A simpler way is if we know when the framework was constructed.  Let’s say, for the sake of argument, that the lower partial denture was done so that the teeth we had for this lower partial that you’re imagining is we had first bicuspid through first bicuspid left in the patient. So, we made a lower partial denture framework.  We made a lingual plate on it so we had an occlusal rasp and a clasp on the first bicuspids, and we had a lingual plate that went around the lingual aspect of the front teeth.

So, if I would say, “How do you know if the partial denture needs a realign or not?”  Just try to make it go teeter-totter across the primary fulcrum line. Can you see if you take one finger, gloved-hand, of course, and hold the lingual plate across the teeth and put another finger on the first molar area of the partial?  See if you can teeter-totter it front to back. Everybody with me now?

If you can see the lingual plate area that’s on the lingual area of the anterior teeth noticeably lift up off the teeth so that when you push down on the molar area, you can see that the back end of the partial tilts down.  Then, that part of the partial framework that fit in the lingual aspect of the lower lingual teeth lifts up in the air and comes up away from the teeth.

You see the only thing that can cause that is if the gum tissue on the underside of the distal extension base has remodeled, as resorbed and reshaped itself. So, the gums under the distal extension base don’t lift up under the partial as good as they did when it was first made.  So, when a brand new partial is put it and you look at it and you look at it to see if it will teeter-totter front to back if it’s a bilateral distal extension, you don’t expect to see a lot of this tipping back and forth on a new partial.

Over time, a year, two, three, four, what’s going to happen is the soft tissue’s going to remodel a little bit so when you go to do that same pushing back and forth, the tissue isn’t supporting the back end of the partial.  It goes down, and your indirect retainer is your point of reference because if that lifts up off the teeth, it’s telling you that you’ve got teeter-tottering.  Question?

The question was, “If you have a class III partial that’s hypothetically supported at all four corners,” so there’s no distal extension and at least according to the record, as much as we can believe the record, the provider at the time said things fit well and everything was okay at the time it was delivered.  You are now the poor sucker who’s doing the recall a year later when you’re cleaning their teeth or doing whatever and you try this class III partial denture in, and it seems like it rocks quite a bit.  It just doesn’t fit on the teeth very well.

We’ll go over class IIIs in a little bit, but if basically your partial denture is tooth-supported all the way around, would any change in the soft tissue, if the gums reshaped a little bit, would that, in theory, have any effect on the fit of a class III partial?  That has nothing to do with it because it’s tooth-supported all the way around.

Now, typically, if a patient is being compliant and wearing their partial on a regular basis, would you expect that the partial denture framework fitting on the teeth will help stabilize the teeth on that position when the partial’s delivered if, in fact, things fit well, which they said it did in the record?  Is that a reasonable assumption? So, if a patient fits like socks on a rooster, there’s nothing really bad.  When you eliminate the impossible, everything left, however improbable, is probably the cause.

So, the patient was either non-compliant and didn’t wear it, which allowed the teeth to shift. I don’t know how many of you have undergone orthodontics, and for those of you that did orthodontics, did you wear retainers for some period of time? If you got lazy because you’re just a human being and you went several days or a couple of weeks without wearing your retainer, when you put your retainer back in, it felt like it didn’t fit so good. It fit pretty bad, in fact. Just after a day or two, things seemed to settle in, and the teeth readjusted to fit your retainer.  Same thing happens with a partial denture.

So, if I have a situation like you have, I either assume one of two things, the patient was non-compliant and didn’t wear their partial for some period of time. It’s been the dresser drawer for some period of time, and they put it in for when they came in to see you. Now, it’s your fault because it doesn’t fit, or they dropped it or the dog got a hold of it because patients lie.

It’s like You’re stopped by the cops or you see the gun machine come up in your rearview mirror, right? So, what’s the first words out of his mouth? “Do you know fast you were going, ma’am?” “No, officer. I didn’t have any idea. I’m the Virgin Mary here. What happened?” You know, people are not the best as saying, “I was doing 20 over. I’m in a hurry. It’s my fault. Put the cuffs on me. It’s my fault.” Probably, if you said that, you could blow the officer over with a feather, and they’d let you off with a warning just because they’d be so blown away that somebody was just so upright honest with them.

So, to answer your question, my greatest suspicion in that circumstance is they were either non-compliant and the teeth shifted or they dropped it and they got banned.  Go ahead.

Did the tooth in question that had this sort of miniscule resin on this tooth, did it have any buckle or lingual dressing on the tooth?  So, the point is that you can have somewhat of a minuscule resin, but if there’s some sort of a retentive arm, bracing arm, or a clasp arm on the buckle lingual part of the tooth, it’s unlikely that it’s going to shift that much if it’s being worn on a moderately regular basis. Again, if the partial’s being worn on a regular basis.  If they’re not wearing it, absolutely.

It’s probably going to keep tilting it, but if the partial’s in place, it runs slant into the approximate on the partial.  Even if the occlusal were to break off, you might get a little tissue irritation around that tooth because in that area the partial would be freely sliding up and down around the tooth, but because of the proximal plate on the partial, the tooth would have a heck of a time tilting more easily if the partial was being worn.

So, again, when I see those things, especially with an all-tooth supported partial and with students because they push you all over the place.  I can’t tell you how many years it’s been.  That’s one advantage in dentistry of getting gray hair. I can’t tell you how many times over the years I come into the cubicle, and I tell the patient verbatim exactly what you just told them six minutes before I got there, and they’re going, “Yes, doctor.  Okay, doctor.  Yeah. Uh huh. Okay, doctor.”  Then, they leave, and then you come up to me after clinic. You go, “I want to send that person to the moon because I said exactly the same thing you did, and they said, “Are you sure?  I don’t agree with you.”

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Dr. Lavine:

Okay.  Do you believe the PSG is critical for diagnosis of OSA or CPAP before treatment?


Dr. Elliott:

No, not all the time.  If the patient has a previous heart attack, if they have high blood pressure and stroke and those kinds of patients that have a health history a mile long or if they have severe tiredness and bad insomnia that maybe you think they have a different type of sleep disorder, then I would definitely request a PSG.  Most of the time, I would leave it to the physicians, and my sleep physicians really are open to home sleep studies. A lot of insurances are even going that way, too, where they require a home sleep study before a PSG.

So, no, I don’t always require a PSG because honestly, patients don’t pursue treatment if they know they have to sleep in a sleep lab, and when you open it up to possibly having a home sleep study, they say, “I can do that.”  It’s amazing how many more people you can help in that situation.


Dr. Lavine:

Yeah. It makes sense.  When you’re seeing adolescents, can you estimate how many percent are being sent for removal of their tonsils or adenoids?


Dr. Elliott:

Of all the children I see?


Dr. Lavine:



Dr. Elliott:

The ones that I send most of the time have their tonsils out because it is so severe.  A lot of times I bypass the pediatricians because they’ll tell that they have sore throat, they’ll outgrow it. They’re fine.  I don’t send four, five year old unless they’re really bad because the surgeons really don’t like taking tonsils out like they used to.  So, when they’re six or seven, they’ll have that long face, that look.  Most of the time, the ENTs are willing to look at it even without a sleep study.  They sometimes bypass the sleep study and take the tonsils and adenoids out.  My hygienist’s niece actually just went, and they put a scope up her nose.  They saw her adenoids were almost 100% blocking her nasal passageway.  So, she’s going to get those out.


Dr. Lavine:

Okay. Two more questions here.  Where did you get the Schwartz Gauge that you showed?


Dr. Elliott:

The George Gauge?


Dr. Lavine:



Dr. Elliott:

Yeah, just on the net.  You can order them online from several different labs.


Dr. Lavine:

Okay.  If someone doesn’t have full blown OSA, will these devices work just to prevent snoring?


Dr. Elliott:

Yes, and I do treat them in a little different way.  With snoring, medical insurance won’t cover snores.  So, sometimes they don’t even cover for mild sleep apnea, but I could get into that more in the course.  With the snorers, I make an appliance that costs less, Silent Nite®.  Like I said, we make those snore-guards, but I know my patients are screened for it.  It’s just snoring.  So, the Silent Nite® is common because it’s cheap.

So, I’ll just do it.  I think we charge $850 for that, or I’ll make them a SomnoDent.   I just charge a flat rate.  As long as my lab fees are covered, I think we charge $1100, and the reason why I can charge so cheap is because there’s no follow-up appointment. I don’t have to do the follow-up appointment or home sleep study.  We basically deliver it, show them how to advance it, and send them on their way.  There’s not much follow-ups for just snoring.  So, you can do a couple of different ways.


Dr. Lavine:

Okay.  We have two more questions.  I certainly want to stress, and I know you’re being modest about this, Erin, but the point of the webinar was just to get people an overview of what’s out there, what they should know about.  I would imagine that your course would cover all of these and a lot more, which is a three-day course, correct?


Dr. Elliott:

Two day course.


Dr. Lavine:

So, that’s a lot of information in two days, but certainly, that was never the goal of the webinar, to get people 100% confident with it.  I think the course would be a good place to start.  A couple of insurance questions here.  If you don’t know if there insurance will pay, do you request a part of the fee up front?


Dr. Elliott:

Yeah, we usually do.  That’s something that I would do in the course, give you the call intake form and insurance verification form, and it sets you and guides you up.  When the patient walks in, we know their deductible hasn’t been met, and they’re going to need this much out of pocket.  We usually request on the day of the impression a $600 down payment.  That will cover the lab fees, and that’s all we care about.  So, after that, if the insurance needs more, we can collect at the delivery appointment.

It’s really hard to convey sometimes to patients.  They don’t understand that it’s mostly paying up front because most of the time if you think about going to the doctor or for surgery, you just wait for the bills to arrive, but I think they can understand why we’re asking them ahead of time.  Most of the time, they’re pretty open to doing that.


Dr. Lavine:

Okay.  Also with insurance, do you have any experience dealing with insurance in Canada?

Dr. Elliott:

Yeah.  You know what?  I’m friends with a Canadian dentist who’s actually doing dental sleep medicine solely now.  She sold her practice, and whenever it comes to medical insurance, she tunes it out because it doesn’t really apply there.  There’s this huge waiting list for the sleep lab so I don’t really know how she does it with the sleep system, but she’s working with a sleep physician now.  It has made her life easier.


Dr. Lavine:

Okay.  This one here is probably a questions for you or Curt, really critical question:  Will there be good snacks at the course?  I love some of these questions.  I assume the answer is “yes”.

Okay, just a couple more question here.  Can finger pulse oximetry used with the [01:36:28] Maneuver reveal a high risk in an OSA patient?  Is it enough positive diagnosis to initiate treatment with sleep breathing or oral appliance without a PSG?


Dr. Elliott:

No, that is not.  The only test they have seen work to use as diagnosis is the PSG, the home study, or a sleep MRI, and they only use that for research.  It may show you if they have a high probability.  It can be used to screen, but it cannot be used to diagnose.  That can only be done by a sleep physician with those sleep tests.


Dr. Lavine:

With all the HMOs out there, you’re not a participating provider.  Can you still submit to those insurance companies?


Dr. Elliott:

Yes, and that’s the trick.  Most dentists I hope do not become network providers because they really lower the fee quite a bit.  I’m in network with [0137:33] of Idaho only because I know the person that’s in charge of it, and they’ve had special meetings for me for this to try to get me reimbursed at an appropriate rate.

If you are out of network, that just means that the patient needs to pay more.  They pay at a lower percentage, or you can get a gap exception so that if there’s no other dentist in a 50 mile radius that is not in a network, then, a lot of times they will cover you as a network provider if that makes sense.


Dr. Lavine:

Okay.  Last question, and I’m sure you’ll probably cover this in the seminar as well in your course.  Is there any one external market method that you have found to be very effective?  Obviously, it depends on the area that you’re in, but have you found luck with print, radio, TV, social media?  What do you find good for you?


Dr. Elliott:

It does depend on the area that you’re in, and I’ll tell you what, I love the marketing part of it.  So, I have all sorts of ideas, and I think it takes a few touches before someone will actually pick up the phone and call.  I have a website, and I have a Microsoft Tag and QR code that leads to my website.  I’m sure most of the patients here don’t even have a computer.  So, social media’s good.  I’ve been on the radio, and there’s such so many ways and so many things to approach people with it because it affects them in different ways.  So, this is something I love talking about it and ideas or ad design, too.  There’s no one thing.


Dr. Lavine:

Good.  Erin, thank you so much.  We had great questions, great content.  I would highly recommend people to consider going to the course.  It’s in a month or so and all of this stuff and a lot more.  You can see the information on the screen.  You can go to their website, to, use the sleep code.  Call them up. We’ve had great luck working with Golden Dental Solutions over the years.

We actually have a workshop in a week or so on using the Physics Forceps. For those of you that are not doing extractions, that’s because you find them very difficult.  This will completely change your life, and I highly encourage you.  If I you haven’t received an invitation, send me an e-mail.  I will get you an invitation, but we already have a lot of people signed up for that one as well.

Thanks, again, Golden Dental Solutions for sponsoring the webinar and making the course available, and they will be providing a free CE for everyone as well.  So, thank you, Erin.  That was fantastic.  I really appreciate you being here.


Dr. Elliott:

You’re welcome.  I had a great time.  I hope people see the need for it and the love for it as much as I do.


Dr. Lavine:

Well, I think it’s great.  It’s fantastic because it’s something, like with all the webinars that I do, that general dentists may not have gotten to in dental school, but we absolutely have the skill set to be doing this. All you need is a little bit of training, a little bit of confidence, and I can see the passion that you have and the passion that your patients have in what you have provided for them.

I think it’s something that we should strive for, to have these happy patients singing praises.  What a great service if you can change someone’s life around.  You don’t typically get that tooth service amalgam, but something like this would change their life.

So, I want to thank everyone for being on the webinar.  Stay tuned for future webinars.  We have one next week with Dr. Louis Malcmacher and Dr. [01:41:08] talking about Physics Forceps. We’ve got more in the future as well

Erin, do you give out your e-mail address if people want to send you a question?


Dr. Elliott:

Oh, sure.  That would be great.  I actually even showed it in the Dental Economic article so I know I won’t get too bombarded.  It’s


Dr. Lavine:

Great.  Thank you everyone for staying up with us this evening.  It was a great webinar, and maybe we’ll bring you back in a few months.  This is a great topic, and there seems to be a lot of interest.  So, thank you, again, Erin. Thanks, everyone, for joining us, and we look forward to seeing you on future webinars.  Good night, everyone.


Dr. Elliott:

Good night.

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