Hello everyone. My name is Katherine Quisenberry. I'm the service head of the Avon and Exotic Pet Service at the Animal Medical centre, and I'm also the chief medical officer.

I'm gonna talk to you today about dental disease management and rabbits and rodents. So we're gonna talk about first the tooth structure. And this is gonna be a review for many of you.

Of course, rodents are divided into different groups. We have the hystrigomorph rodents, the myomorph rodents, and the serum rodents. We're only gonna talk about the hystriomorph and the myomorph rodents today.

The hystrimorph rodents are the ones that we Continually see for dental disease problems. This is the guinea pigs, the chinchillas, and the dagus, ra rabbits, of course, are not rodents, but we see the same dental problems that we do in the hystriomorph rodents, and this is because these groups of animals have ilodont teeth which are continuously growing cheek teeth. They have A very large crucial surface, and that is adapted for grinding.

They consume grasses and vegetation. So on, for example, here this is a a cast of a the dental molars of a chinchilla, and you can see the very grinding and irregular tooth surfaces that is similar to a cow. The myomorph rodents and the seromorph rodents are the rats, the mice, the hamsters, the gerbils, and the squirrel family.

They have annelidont teeth, which are short crowned rooted cheek teeth. These teeth do not grow. These are primarily.

Rain eaters, they're omnivores, so we don't see these animals, very often for dental disease. We do see them for, problems involving their incisors, which we're not going to talk so much about today in this group of animals. So the dental anatomy of these rodents vary and of rabbits vary.

They're, as I said earlier, they're very adapted for a very highly abrasive diet, and some rodents, you note that the incisors are yellow, and this is because there's an iron pigment on the surface. Of these incisors, which makes that the cranial surface very, very hard. The back of the tooth has a softer dentin surface.

This allows for these teeth to become very sharp for chiselling, a chisel-like, structure, and that allows a very sharp edge for cutting. So the chewing motion of these animals differ according to their diet and their structure and their anatomy. Rabbits, their incisors have a vertical action which is used for cutting, and this is, their jaw anatomy you can see is a little bit different.

They have two sets of incisors, so they have this vertical action which can Cut grasses and then as they move the grasses back they have these cheek teeth which have a wide lateral chewing surface so they have the power stroke of the molars of the cheek teeth is horizontal with any sort of vegetation and that allows wear on the teeth. To ruminate cows, the power stroke is more vertical, and that's what they need to chew pellets, but that doesn't cause the wear on the teeth that the horizontal motion does. In rodents, they have incisors that adapted to a rostrocoal gnawing motion.

And they have mas masticatory muscles that are adapted for this rostrocaudal action. They have a shorter diastema schema in their mandible, and this allows for this brachynatic appearance. The natural diet of most herbivores, which is the rabbits, and the rodents in the groups that we're talking about, the, the, chinchillas and guinea pigs, they eat primarily grasses and low growing plants.

They have limited jaw opening and their incisors are used to slice. The grasses are moved into the mouth and chewed with a wide lateral jaw motion. So the molars are used for grinding.

Natural grasses contain very abrasive silicate vitallis, and these caused marked tooth wear. This is a an enlargement of a grass, and you can see all these little crystals here which are the phytalists which cause wear on the teeth. So house rabbits, guinea pigs, chinchillas.

Pet animals, captive animals are usually fed high amounts of concentrate, and this causes a reduced lateral chewing motion and reduced wear on their teeth. So they have very small amounts of abrasive grasses, and this also causes reduced wear. What happens is that this results in uneven apusal wear.

Elongated roots and spikes on the buccal and cheek surfaces as the teeth grow. Rabbits have a dental formula of 2 incisors, 0 canines, 3 premolars on the top, 2 on the bottom, and 3 molars, and the not the notation of the teeth really varies according to what source you read. There's the modified triadian.

Which is similar to other animals used based on the pig's tooth tooth anatomy, and these divide the teeth into quadrants, upper right is quadrant 1, upper left is quadrant 2, lower left is quadrant 3, lower right is quadrant 4. So, and these number the the teeth according to the number of quadrants. And and and where they are in relation to the anatomy of a pig.

So here we can see the upper Teeth here, the 3 molars, the last molar, the third molar on the upper is a very, very small tooth, and then the 2 regular size molars, and then the 33 pearl molars. The other way that people talk about these is just cheek tooth 1, cheek tooth 2, cheek tooth 3, and so on. And then of course they have the second smaller incisor behind or the peg tooth behind the first incisor.

This is from Capello's book Rabbit and Rodent Dentistry. Again, how the different ways these teeth are talked about pre-molars 12, and 3, Mueller's 12, and 3. He's a lateral anatomy of that.

So again, it depends on how this is talked about. So the jaw anatomy of a rabbit, the TM joints, at rest, the incisors are basically in occlusion. So, you can see here this is an anatomy at rest, the incisors are in occlusion here.

A lot of times the occlusion is with the peg tooth. And then when, the incisors are in motion, there's no, occlusion of the cheek teeth, but when the cheek teeth are in motion with the lateral motion, there's no occlusion of the incisors. Incisor maloclusion in rabbits is due primarily to genetic factors.

It's an autosomal recessive gene. It can occur sporadically in breeding stock. These rabbits have a short skull in relation to the mandible, and this results in the overgrowth of the lower incisors.

The lower incisors grow up and out. The upper incisors grow in and back and usually curl around. These signs are usually present in young rabbits, and the prevention is by culling.

We'll talk about the treatment of this in a bit. This was a study from 1995 by Frances Harcourt Brown, and it was an interesting study. What she looked at was the bone quality of skulls of rabbits that were kept as pets versus rabbits that were in the wild.

And what she found was that in the pet rabbits they had Very poor bone quality compared to the wild rabbits. The teeth fell out of the sockets. There was markedly thin bone.

And there were ectopic tooth roots. At that point in time, this was again in 1995, so this was 25 years ago, but this was thought to be related to the what they called chafe diet, which or chaff diet, which is a mixture of hay and grains which had a very imbalanced calcium phosphorus ratio and a lack of vitamin D in these house rabbits. So that emphasised the importance of a balanced diet in domestic rabbits.

Since that time, of course, the pelleted diets have become more or less universal for pet rabbits, throughout the the world. This is a nice illustration. Teeth overgrow in rabbits, and you can see that the Lower cheek teeth will develop points, and these points on the lower cheek teeth will impact the tongue, sometimes cause severe lesions in the tongue, whereas the points on the upper cheek teeth are gonna impact the buccal surface of the teeth, and this is uncomplicated dental disease.

We're not talking about abscesses or or tooth root, necrosis here. So what happens with root elongation and how these, these points develop is that whenever there is Where, so these animals are not eating the, the, grasses that have a lot of abrasive surfaces. They're not eating enough hay, they're eating more concentrates.

So as this happens, that lateral motion is not enough to wear down the teeth, so Because of that, the eruption is reduced or stops because it's the occlusal pressures are decreased from the reduced wear. So the teeth continue to grow, but the teeth do not continue to erupt. So when you look in the mouth of these animals, the occlusal surface may appear normal, but what happens is the tooth roots start elongating because that growth has to go somewhere.

So here you can see there's decreased. Where on the teeth, the points start developing on the medial surface of the lower teeth, the lateral surface of the upper teeth, and these points can become quite enlarged, and then as time goes on, there's increased pressure on the roots, there's a lateral and medial pressure on the teeth, so the teeth start beginning to Curve here and those points become even more long and at this point the rabbit can't chew normally and then what you end up with is this very abnormal curved teeth with long points and once you're at this stage of the game, it's, you can't go backwards. Only the only thing you can do is really maintain it.

So in pet rabbits, we see molar male occlusion, which is most common in middle age to older rabbits. We see incisor occlusion, which is common in young animals, which we talked about has primarily a genetic factor in older animals where you see incisor molecule occlusion. This is primarily anatomical, and this is because of a change in the mandibular position from the molar m occlusion.

You can also have a change in tooth alignment from abnormal wear from the food types which we talked about infection of the roots, which is quite common. Connective tissue abnormalities which we alluded to in a study by Francis Harcourt Brown and of course genetic factors. So there's many different theories as to why dental disease is common in these animals, but we need to remember the most obvious ones.

The clinical signs of maleclusion can be obvious in the case of incisors or very vague in the, in the case of cheap teeth abnormalities. The animals can act hungry, but they can refuse food. There in some species, you may see excessive salivation.

We don't see this very commonly in rabbits, but we certainly see it in chinchillas and sometimes in guinea pigs, but primarily in chinchillas. Some rabbits especially will develop a honking upper respiratory sound, and this is because of the molar root elongation which impacts into the nasal passages and the nasal turbinates. On physical examination, you need to do an oral exam.

Of course, in many animals this is limited, one, because of the size of the oral cavity, and 2 because of access to that area on a normal physical exam. So the best you can do in many situations is to get a quick idea of what's going on in there. And we like to use this nasal speculum which Allows it has a light source and you can very easily see, what's going on back in the oral cavity.

And when you're doing this, you wanna make sure that you do not upclude the nasal passages here. So you want to be careful about how you're restraining this rabbit to get a good look in the mouth and again, just getting a good look in there. A lot of times this is looking at both arcades, but many times what you're gonna do is a position.

The speculum, so you look at one arcade, the lateral and the medial surfaces, and then you move your speculum and you focus on the other arcade and the lateral and medial surface. For most animals, this will at least give you an initial idea of whether or not a dental problem is what's causing clinical signs, but it should be routine on any animal that you do a physical examination to to examine the The oral cavity in these animals with ilodont teeth. Again, this is the nasal speculum with the light source, holding the animal to do that oral exam and and just getting a good look in there.

Do we do see ocular discharge? With some animals with dental disease. So I just wanna bring your attention to this.

It's certainly not the most common presentation, and most animals with an ocular discharge actually have upper respiratory pastorella, or other. Bacterial infections that's causing the discharge, but in some animals, it can be related to tooth roots. So just so you're aware of that again, because the root elongation of the molar upper cheek teeth can impact on the nasolactinal duct.

And so to to determine this, you would need to do imaging studies. This is a nice illustration of the path of the nasolacrimal duct here, and you can see how it goes right above the roots of the molar teeth and also the root of the incisor tooth. So if there's an incisor tooth problem that can also affect the nasal lamal duct here.

So you can do a contrast study of the nasolacrimal duct here if you do suspect and you can see it nicely here where the cheek teeth roots are very, very close to this duct, and here again, here's the root of the upper incisor and where that nasolacrimal duct is very, very close to the root of the upper incisor and again here. Imaging is very important in doing dentistry. There are many papers and books written on imaging in rabbits and rodents with dental disease.

For the last Probably 20 years we've relied or or 30 years we relied most commonly on skull radiographs, and these certainly are important and they have a place. You should take skull radiographs because you can get important information on these. That being said, CT which I talked about in my other lecture and I'm gonna talk about here, has pretty much replaced skull.

Graphs where it is available for use. Here in this radiograph we can see there's root elongation. You can see how the ventral mandibular jawline has been disrupted by the roots of these teeth, and you can also see an elongated point here, and again elongation of these tooth roots, and you can see there's some abnormalities of the ousal surface.

So you want to examine the line of the mandible here. Again, it should be a nice smooth line, and evaluate the roots also for any evidence of licence. This is a normal radiograph.

You can see the normal incisors here, nice, curvature, normal cheek teeth here, and you can draw lines and see if this looks like a normal anatomy. It should be completely horizontal parallel. There should be also a horizontal and parallel tooth root surface of the molars.

Normal curvature of the premolars. This is an abnormal skull radiograph and you can see big differences in this one. So you can see the angle of the jaw now is wider anteriorly, it's not parallel.

You can also see there's abnormal curvature of the premolar. Abnormal horizontal axis of the cheek tea. And there's also two through elongation, and Evidence of abnormal mandibular lower jawline.

Again, computed tomography has replaced a lot of, of the dental radiographs. So again, this, this is a normal CT of a, a rabbit, and we can see here the upper incisors which are lucent here. You can see them, the lower incisors are more opaque in this view.

And as we go further back, I start to see the nasal passages, the cheek teeth, and Look at the curvatures and look at the jawline on this this is a Cranial view, and you can see again nice alignment of the cheek tooth throughout this. For the hystriomorph rodents, they have a slightly different dental anatomy. Again, these animals are more benigning type of rodents and There as you can see the skull, the upper right skull here is a guinea pig skull.

The lower right skull is a chinchilla skull. You can tell the difference by the size of the bulla here. Chinchillas have a very large bulla.

There's also a difference in the angle of the jaw, which we'll talk about. Guinea pigs and and chinchillas have similar Cheek tooth anatomy. They have 3 molars and 1 premolar.

It's hard to tell the individual teeth here just because of the tooth structure and how they're they're sort of, sort of meld into each other basically. So it's hard when you're in there doing a dentistry to determine which molar is which sometimes. You can see the different angles of their jaw.

So here's a chinchilla here. You can see the yellow pigmentation of the lower, incisor teeth, but here you can see the pre-molars and the molars have a more upright appearance of the jaw and the chewing service is more upright, whereas in guinea pigs they have a very Planted lateral and medial orientation of their upper and lower molars and pre-molars. So this is a normal guinea pig, occlusal surface here, very, very, lateral medial type of orientation.

So what you're looking at, what happens with these guinea pigs is a lot of times as their tooth roots elongate, the, the common presentation is that these clusal surface will become so long that the tongue will be entrapped below these lower premolars and molars. So in guinea pigs, again, root elongation occurs, the molars and pre-molars are pushed apically and it's caused by maleclusion, loose periodontal ligaments, no abrasive food, or a calcium phosphorus vitamin D3 imbalance, and the occlusal surface may appear normal, but the roots are extremely elongated. So this is a Radiograph of a chinchilla here you can see because of the large bola up here we know it's a chinchilla, and here you can see a normal chinchilla, normal anatomy, nice horizontal occlusive surface of the teeth, nice incisors here.

Here's an abnormal chinchilla, and you can see really severe abnormalities of the cheek teeth. And you can also see pretty extreme curvature of the upper incisors. Here you can see this animal actually actually had a broken lower incisor and on this view, this sagittal view here you can see this the broken incisor lower incisor here.

Guinea pig, this is showing guinea pig with severe root elongation. You can see here the molars are so severely elongated that it's actually widening the mouth, and it's not that nice horizontal. Frontal structure here, the mouth is gonna be more wide.

These guinea pigs often look like their mouth is open, and these are the ones that you're gonna see with incisor elongation. So if you see incisor elongation in a guinea pig, you wanna think of a tooth root problem. And a molar problem, not an incisor problem.

So we do routine dentistries in these animals. Tranquilization is necessary to do a good dentistry. There's many different protocols.

The one I'd like to use is using dexametatomidine and ketamine, and then supplementing with an oxygen flow by, and that's illustrated in this, example we're doing a dentistry here in a rabbit going in with a ranjour to probably clip a point. But we have the animals set up in this apparatus which I'll show you with the flow by oxygen here over the nose, of course, rabbits breathe through their nose, so it's just important that you cover the nose and and then we're able to do an a routine and thorough dentistry here with the rabbit sedated. In other procedures where you have to Pull a tooth, any sort of flushing, anything like that, then, of course, you must intubate the animal to do that.

So any sort of dental abscess surgery, jaw surgery, tooth roots, or pulling a tooth that is complicated. This is what we're doing here. We pulled the tooth and we're actually trying to, suture the gum line back after we've, pulled that tube.

But you can see here we've got the tube placed at 2.5 in the tracheal tube. We have the tube suture on either side of the, the upper mandible, to the skin, so there's no movement of that tube while we're doing the dentistry.

So through this, if you are using a tranquillizer and you are doing oxygen flow by, it's very important to all this to watch the breathing, keep the neck extended so there's no occlusion of the trachea or, or any cause to cause some problems with that animal breathing. You want to get the right dental equipment, and these are readily available now. You can buy the rabbit and rodent dental packs.

You also wanna have a small bone lojour. This is very helpful for these . Clipping off these small little points, you wanna have these files, these diamond rasps are sometimes helpful, in some occasions we don't depend on them heavily, but they can sometimes be used after you remove a tooth.

With the dental unit or if you're clipping something or if you just need to take a little bit of the edge off in these very, very small nails where you can't fit a bone or a dental burr, to go back in there with the and file it. Different types of instruments to try to to use for tooth, tooth tooth extraction. These larger ones are stalled with a rabbit oed dental packs.

And the smaller you can use different types of hemostats that are right angled, and those are very helpful as well, and also other dental equipment that you get from a small animal dentistry supplier. I always use these little spatulas to move the the bumucosa out of the way so I can see the tooth to protect. The gum line or as I'm doing any sort of drilling, I use these sometimes.

Another instrument that is very helpful is this type of instruments which you can use to move the tongue out of the way and also to move the cheek mucosa out of the way. It's more curved, so that's a very helpful thing, and then the different sizes of the, the speculums. You have to have some sort of dental unit, dental drill.

We have this old shine unit. I think this one's probably about 20 or 30 years old, but it still works really well. And then you wanna use some sort of dental burr.

We exclusively use these diamond drills to do the dentistry. They're very safe as opposed to the regular dental burrs that have a very, sharp cutting edge. If you hit the mucosa with the the regular dental burr, you're gonna get bleeding, whereas if you use these diamond burrs, they're, it's not so harsh on the mucosal tissues and .

And you don't, you're not such a high risk of bleeding. You can buy these bird protectors as well, and they fit right over the dental unit so you can have your burr out here. Those are very handy and tight spaces where you can't use some sort of speculum to keep the mucosa out of the mouth.

So again, you want to use these diamond burs. Dental restraint devices, there's several on the market. This is one sold by IM 3.

It's very commonly available. This is another one that I think is not quite so available anymore. This is the one that we've had and used for many, many years, and it's very nice cause you can, really.

Fix it so the animal is, is positioned exactly how you want it, same with these, this one you can, both of them you can actually change the angle or how far up or down you want in position because you're gonna have some sort of tilt. So you wanna place these animals on these restraint devices with a cheap dilator. You can either place the dilator.

Up or the dilator down, it's really personal preference and how you best work. You can use auto endoscopy, and this is very useful. We, I personally don't use auto endoscopy so much because I, instead, I use magnifying, glasses and, a light source on my head.

So that takes the place of the odour endoscopy and I find that that is very useful because I don't have another instrument. But you can use those endoscopy to give you an idea of what's going on. Looking at the molars and the molars of a rabbit here, you can see these sharp points back here.

He's a very Obvious start point, this looks like first molar here. Incisors we talked about, so this is how you would deal with this if, if these are an incisor that's overgrown, and it the the problem with these is that because these teeth are continually growing, of course this is something you're gonna have to deal with over and over and over again. So you want to, trim it, usually sedation is necessary, not always, it depends on the animal, .

So the way we trim these is usually using a diamond burr, a diamond disc burr on our dental unit and we place something behind the tooth so we make sure that we're not gonna be able to cut the teeth or anything and we just simply burr that down, cut it off, it takes about 1 2nd to cut it off. Now, if It's a situation, well, this is in a chinchilla. You can see we're cutting the tube here.

These teeth are over elongated so it's actually got a secondary incisor or split incisor growing here, that needs to be cut. Pre-molars and molars, if you want to remove any points, the dental drill with the diamond bird, as we talked about it, you can also for very small points just use the longjour and take the point off and then follow that with just the diamond file if you need it to smooth the area out. If there's crown elongation, you want to reduce these elongated crowns, and you do need to do the dental, use the dental drill again with the diamond bird.

You want to make sure that you always inspect all surfaces, the buil surfaces, as well as the lingual surface. So here's a rabbit mouth, and we can see here very abnormal toothro here. You can also see the teeth are extremely discoloured, they're brown, they're not healthy teeth, and this tooth obviously has to be taken care of.

Nice view of the mountain. Again, you want to check all mucosal surfaces. This is showing using the dental drill to bur this tooth down here we've got the the speculum on the other side holding the tooth mucosa out of the way while we're drilling this.

Likewise, we would put the speculum on the side of the tongue to hold the tongue out of the way to get the more medial surface of the tooth. So here we're doing all this. Here we're using a longer to go in there and just snip a tooth, and then we can follow that up with the dental drill as needed.

So it really depends on where you are, what the anatomy is, what you're gonna have to do if you're gonna use the dental burr to remove the points, or if you're going to use the laundry to go back in there and snip the point and then smooth it out. But you want to try to get the anatomy as close to normal as you can. The extraction of the teeth, the cheap teeth, usually this is, well, always because this is, diseased or abscess cheap teeth associated with mandibular abscesses, and the extraction is usually necessary or the abscess will not heal.

And rabbits, you know that if you have a mandibular or axillary abscess, if you simply open the abscess and try to drain it, that's not gonna solve the problem as we talked about you have to go in and find out what the cause of the problem is and resolve that before you can. Heal these ailments and heal these lesions. So for the most part, we do try to use an intraoral approach unless the tooth can be removed through the abscess cavity, and that is usually pretty much involving the mandibular tooth, and you would go into a ventral la mandible for an extraor approach.

Post-operative on these animals, animals usually begin to eat within 2 to 3 days after any type of dentistry. You do wanna use postoperative pain management, whatever your favourite pain management is, force speed, of course, as necessary. After you do the dentistry, if the appetite remains poor, then oftentimes you miss something.

So if a week after a dentistry and the animal's not eating normally, still dropping, pellets, not wanting to eat normally, you need to go back in and see if you missed something. But if you've done a thorough dentistry to begin with, hopefully you didn't miss it. Long-term management of malocclusion involves examining for the animal for a dentistry every 1 to 6 months is needed.

Certainly if you're going to manage incisor maleclusion, you're gonna have to be seeing these animals every 6 weeks or so. If it's a dentistry, it really depends on the severity of the disease. As well as the species, some rabbits probably need a dentistry maybe every 3 months, some every 6 months, some every year, depends on, on the animal, and of course you want to correct the diet down at the bottom.

You've got to encourage these animals to eat more hay, to encourage more lateral chewing motion. Definitely need to, a lot of these animals we talked about, I find, and this is anecdotal, but I find a lot of the animals, certainly the animals with Brown teeth, tooth root abscesses, when you question the owners or question what these animals have been eating, a lot of times they've been fed sugary, high sugar, simple carbohydrate foods such as, fruits like bananas, bananas are a big culprit or treats that have honey in them or something like that. So you wanna make sure you correct the diet, try to get them on a high grass hay diet.

If it's incisors, you want to call the breeders, call any infected rabbits, and keep the incisors trimmed. So in the animals that you don't want to, or the owner doesn't want to do routine, trims on the incisors, certainly incisor extraction is described and is done quite frequently in many animals. They can certainly live a normal healthy life without visors, so certainly it's also indicated there's any incisor tooth root abscess.

So it does require full anaesthesia. You need to pay attention to fluid therapy and pain management because it is painful having a, a tooth pulled, and you need to make sure that the germinal tissues are destroyed and removed or the tooth may regrow. So for incisor extraction, you want to break down the ligaments with an elevator and you use a rotating motion for the medial ligaments.

You pull in the direction of the curvature, and a lot of times this this pulling is more of a a gentle continuous pressure. It's not a 123 type pull. It's a more chronic, not chronic, but just continued, .

Pulling in the direction of the curvature until it loosens. You wanna make sure that the, the teeth are very, very loose before before you try to extract them and that the ligaments are all broken down. Just from a practical standpoint, you want to extract the lower teeth first because they're in your way, and then you inspect the tooth root for the soft roots.

So again, here we're breaking down the ligaments on these lower incisors. We're getting the tooth really. Loose before we try to extract them.

So, that's the hollow soft root of the tooth. That's what the upper incisors look. You can see how curved these upper incisors are.

This is an animal where the tooth was not extracted very well, the tooth root and the The ciser actually regrew and it grew up through the nasal passage here. You can see this root growing straight out here. So that's why you wanna make sure that you get the whole root out when you extract these teeth.

So I wanna talk a little bit more about dental abscesses. Usually these are mandibular. If they are maxillary, they can be retrobulbar from the upper molar.

But the other thing I wanna point out is that these retrobulbar abscesses can track up from the mandible through the sinus, and I'll show you an example of that. So don't. Obvious, don't always assume that if you have a retrobulbar abscess that it's gonna be from an upper cheek tooth because that's not always the case.

Usually there's a retained necrotic tooth root that has to be removed before you're gonna be able to resolve these issues, and they can be associated with diets high in simple sugars, like I talked about bananas and treats. So you always wanna make sure that you ask those questions and then correct the diet. This was a study that was done many years ago and it's still referred to today where it was the type of bacteria associated with the periodonal abscesses were cultured and what was found was where we suspected or it was thought before this that these were associated with pastorella.

What we found was that was not quite the case, that these are. Often associated with anaerobic and facultative anaerobic bacteria. These are things like Fusobacterium, tinomyces, Heptostreptococcus, pre preatella, and Streptococcus milleri group.

So when you're treating these dental abscesses, you wanna make sure that you are covering with antibiotics to cover for these anaerobic bacteria. No growth, if you culture these, no growth from the lab often indicates an anaerobic bacteria is present. If you are culturing these, you have to make sure that you send these in an anaerobic transport tube.

Many streptococcus species are considered normal flora, but if you get the strepmilari group, those are considered aggressive pathogens. So, the flora, what happens is in this periodontal. Area as the tooth root abscess progresses, the fluoride around the teeth shifts from gramme positives to these anaerobic gram-negative, and then you get resulting gingivitis and periodontitis, and then these deep perapical abscesses have polymicrobial floor.

So again, you want to cover these with broad spectrum antibiotics. Usually, we're using combinations such as injectable penicillin and metronidazole orally to treat these animals. So clinically, what you're gonna find these animals may or may not be anorexic.

Sometimes they are continued to eat like nothing's bothering them, but the owners do notice a swelling on the side of the face. You can palpate these palpable masses that are associated with either the lower or upper jaw. If it's retrobulbar, you will notice bual on one side of the face face as opposed to rabbits with, thymomas where you're gonna have euphemia of both eyes, so this is only on one side of the face.

The oral exam, it may look absolutely normal. You may see nothing in the oral cavity. You may see very flattened, tooth roots.

You may see these teeth that are flushed with the, oftentimes flushed with the mucosa. You don't actually see the crown of these teeth, or you may actually see purulent discharge around the teeth. Most of the time these have some degree of poor dentition.

They're not gonna have normal dentition. Diagnosis of dental abscesses, the the best way to do this is with a CT exam because this is gonna tell you exactly which two groups are involved, exactly where the problem is, and you'll know what you have to go in on. You can also do radiographs, and that will also give you some good information, .

In this example on this radiograph we can see here just really extensive bone proliferation here, these very elongated tooth roots, but it is difficult to tell which tooth root, you know, this tooth roots involved likely this tooth root, so you're not gonna, you're gonna have to go in there on this side of the jaw, this from this. Like you, you know, you have to go in and remove these roots of these teeth, but it's kinda more difficult here on this, soft tissue view, an axial view on a CT scan, we can see this euphemia in this rabbit's eye and this really extensive retro bulbar abscess that's in the sinus of this rabbit, which I'll show you a little bit more about that. OK, so this is a rabbit with a CT image and we can see here this is a soft tissue window, so we're not seeing the teeth so well, but we can see the, the bony or the soft tissue abnormalities associated with the abscess.

So we're going back through the mouth here and we get further in the mouth, then we can start to see some that abnormality on the right side. You can see that huge abscess here, and you can see that this abscess is not from an upper cheek teeth, but it's actually resulting from this lower cheek teeth where this this tooth, this bone hasn't really blown out, and this abscess developed here is tracked up through the sinus and cause this retrovular abscess. This is the bone view of that same rabbit.

And you can see here. Again, we're going back and there's the, the tooth root there that's causing this abscess to form. So this is what we knew we had to go in and find, which is not always easy to go in and find that toothruit.

We're lucky that we do have veterinary dentists that work with us. Here you can see that toothru is right against the, the, . The bone, the bone, thin bone, that's left of the mandible here that we had to go in and remove that too through.

Be able to deal with this rabbit. This rabbit did very well. After we remove them.

So the treatment of dental abscesses, you need to identify the affected tooth roots and extract them. You wanna do a complete surgical debridement. You want to manage that open wound.

You can do this a number of ways. You can use some sort of antimicrobial packing. You can use an antibiotic impregnated gauze or antibiotic impregnated beads, which we'll talk about.

You also again need to put the animal on some sort of systemic anti antibiotic therapy, penicillin, chloroquinolones, metronidazole. You wanna use some sort of combination therapy. So, we Pretty much always use penicillin in using in treating these animals because it does work pretty well so you can use penicillin Daytrol, you can use Baytrol metronidazole, either way.

This is an animal that we resolved the dental abscess, we removed the tooth root in here we're we're trying to deal with the abscess, and you've probably seen animals and in the literature describing man mandiulectomies. To resolve some of these, that, in my opinion, is extremely drastic, and we do not do those, and we've had animals, routinely do well without that radical of surgery. So again, you've gotta go in, find the affected route, remove it, and then you treat the abscess and there's different ways here we're.

This abscess with a silver impregnated gauze, and we're packing it, taking up all the dead space. The beauty of this is that you can leave that packing in for 5 to 7 days depending on, how, how, the people can come back, how often you can deal with the stress. But, maybe in the beginning you might wanna be changing every 2 to 3 days, but it's meant to be late left in up to 3 to 5 days, and it looks, not very nice when you pull it out.

It's usually, absorbed, it's very wet, it's very brown, but, we, we pack these for 3 to 4 weeks and usually they'll, you may have to do further debridement in there, but then they'll go ahead and heal. Another method that some people use is using antibiotic impregnated gauze. So you just get gauze strips, put the antibiotic in there in the strips, and then pack the abscess with that.

Another way you can deal with these, and it depends on what you're trying to treat is to use antibiotic impregnated bees, and we, most everyone has prior to the last two years used these polymethyl methacrylate beads that you make yourself, out of polymethyl methacrylate and you, mix them with an antibiotic. It provides a high local concentration of antibiotic with low systemic absorption. The antibiotic elutes from the beads rapidly and then slowly over months.

These are effective for about a 3 millimetre area around the beads. They work best in bony pockets in my experience, but the downside of these is they can. Then act as form bodies, and you can get biofilms developing on these beads and in many cases they have to be removed.

When these were first used in human medicine and now, certainly if they are being used now, they're almost always removed. They're never left in because they do form these biofilms which you have to get out. So in rabbits and in exotics, that's not always possible to remove them, so that's the the problem with these using these beads.

Now, recently in the last couple of years, a commercial calcium sulphate bead has come on the market. This is made by a company called Carrier. You can order them in carrier.com.

And there's information, lots of information out there about using these beads if you're, if you want to try them, and I would encourage you to use them if you're gonna use beads because the advantage of these beads is that they're fully absorbable over 3 to 5 weeks, so you don't have to worry about a residual form body in there. They have a very predictable illusion. They are also osteoconductive, so you can put them in dead space in bones in these bony cavities, and you can also use them in soft tissue areas to fill the dead space, and they will resorb.

So, they are a little bit expensive, but You can, gas them, keep them on hand, sterilise them, and then use them over a period of time, and there's information in the literature out there about how long they you can keep these, and they have mixing guidelines, how to mix them with antibiotics. So the takeaways from this is that in these animals that diet is a key risk factor for dental disease and companion robots and rabbits and rodents, and you have to have proper equipment. For doing these dental procedures in these animals and if you have access to a CT scan, that is really optimum for dental imaging in any of these animals so you can plan how you're best going to To treat the animals.

So, I thank you for your attention and I hope you've gained a little bit from this lecture, and I wish you luck in managing your dental cases in the future. Thank you.