Diagnostics That Transform Dentistry

Jim Berry: [00:00:00] Welcome to the WSAVA podcast. Today's discussion focuses on diagnostics in veterinary dentistry and how early detection can change both treatment decisions and outcomes. As you listen, consider this, what might you miss if diagnostic tools are underused? Our interviewer Izzie Tsai speaks first with Ana Nemec and later with Jan Bellows. Let's listen in. Izzie Tsai: Dental radiography is often thought of as a technical skill, but WSAVA dental guidelines say it is a basic part of veterinarian dentistry. From your point of view, why is dental radiography essential and not optional? Ana Nemec: Important findings are detected in almost one third of teeth without clinical lesions in dogs and with a bit over 40% of teeth without clinical lesions in cats. In other words, that would mean [00:01:00] that even if we do the best oral dental examination, and we are not taking radiographs. We are missing a huge proportion of clinically important findings that change our treatment approach and our consultation with a client. Radiography at minimum is essential and nowadays we are also moving to use cone beam CT or even CT in certain cases as superior, but radiography at least, is a minimum database to work up our dental patients. Izzie Tsai: Okay. Studies show that we can miss a lot of dental disease if we only rely on clinical oral examination. What kinds of dental problems are most missed without dental radiographs? Ana Nemec: I will just go straight into the problem of tooth resorption. In cats especially, it's impossible to diagnose the type of tooth resorption, so inflammatory and [00:02:00] replacement resorption, which changes our treatment approach. We all know that any tooth with tooth resorption that has type one or inflammatory root resorption needs to be removed in total. For example, coronectomy, just removing the crown and leaving the roots behind that will not work if we are not properly planning that based on radiographs. The endodontic disease, even teeth that do not have pulp exposed but are fractured may have signs of endodontic disease, so we would definitely miss periapical lesions if we are not taking radiographs. Certain aspects of periodontitis can be missed, root fractures impossible to diagnose if there is an edentulous area, we need to do a radiograph to see what's there. Unerupted teeth and certain other congenital abnormalities, they would need radiographs and also anatomical variations, for [00:03:00] example, we all know that maxillary second premolar tooth in dogs is most commonly two rooted, but it can also have three roots. We can get lost if we are not taking radiographs before we plan an extraction or endodontic treatment. Izzie Tsai: Can you share a common case where the mouth looks fairly normal, but radiographs show important disease? Ana Nemec: What I touched upon in our previous question, areas of missing teeth with completely normal gingival soft tissue covering the area, are an absolute indication to take radiographs. Edentulous areas may really be edentulous, so no tooth has ever developed or it was previously extracted. Root fractures can be there. Very common in the maxillary incisive area in cats, everything looks normal and you took radiographs and you see all those little roots of all six incisors or then as I mentioned before, unerupted teeth which may cause dentigerous cysts, for example, very common in boxer dog breeds. So [00:04:00] absolutely there are other indications where clinical exam or our clinical picture will underestimate the extent of the problem. Izzie Tsai: The WSAVA Dental Guidelines recommend full mouth dental radiography as part of a completely oral examination. In daily practice time and costs are real concern, if a full mouth series cannot be done right away, how should vets decide which teeth to radiograph first? Ana Nemec: So the topic of time pressure, I simply do not believe that time pressure should be a reason to compromise on the workup of our patients. We ourselves would probably not feel good if our doctors would be rushed and they would skip diagnostic tests because they don't have time. So that is simply not the way I think we should work. We should focus on being comprehensive in our workup and treatments. In our clinical setting, which is a teaching hospital, so it may be a bit slower, but then again, [00:05:00] it's not that slow either. Average dental procedure takes an hour and a half from diagnostic parts to periodontal treatment to any necessary other treatment. From that hour and a half up to 15 minutes is usually required to take full mouth radiographs, depends bit on the size of the animal, but generally 15 minutes. I would not believe that 15 minutes for a full mouth series is a lot of time for a test that actually brings us so much information. Costs definitely differ or cost policies differ. If we think that this is a very important diagnostic tool, the cost of the radiographs is not reaching even 10% of the total procedure. It brings us a lot of information on how to properly handle the patient. I don't think cost should be an excuse not to take full mouth radiographs. What will happen is that with taking dental radiographs, we will see much more pathology and that [00:06:00] is what will increase the cost of the total procedure because we will have to do more. But then again, it's just not correct not to perform dental radiography and live in false hopes that everything will be done for lower costs. These are the two aspects. Another option is how to stage our cases. In our setting, we would normally do everything in one anaesthesia, meaning from dental radiographs, to periodontal treatment, to other treatments. But there was also an option of a different approach where one may elect for staging into diagnostic parts. So one anaesthetic event for performing charting exam and dental radiography, and then schedule the patient for treatment under another anaesthetic procedure. There is no good and bad or right and wrong. It's just different approaches that may also help you better discuss with the client the findings, as well as better estimate the costs, as [00:07:00] well as better estimate your time for procedure that will actually happen down the road. Izzie Tsai: Okay. Before we talk about interpretation, image quality is very important. What makes a dental radiograph good enough to be diagnostic? Ana Nemec: There are a few rules that we should observe. First is proper angulation, so there should be no elongation, over shortening, minimising horizontal overlap of the anatomical structures. Then the second rule is adequate isolation of the roots with at least two millimetres around the apices so that we can really evaluate the apices of the teeth as well and definitely also adequate exposure and developing techniques so that we achieve proper contrast, clarity, no artefacts on the images. So technical quality of the radiographs is absolutely a must before we go to interpretation. Izzie Tsai: What are the most common mistakes you see when taking [00:08:00] dental radiographs and how can vets fix them? Ana Nemec: So I touched already on the problem of elongation and foreshortening and that is easily corrected with adjusting the x-ray beam. It just takes a bit of technical skill or training. Then artefacts on the images, they can come either from damaged films, so films that are damaged should be discarded and new films used. Izzie Tsai: Yeah. Ana Nemec: Scratches on the films will obscure our evaluation or dirt. If blood gets on the film from the sensor it can also be visible, obviously, on the radiograph. And then under exposure, over exposure, is adjusted by adjusted the exposure times. Most of the mistakes are relatively easy to fix and correct. Izzie Tsai: For students and young vets, choosing between the parallel technique and the bisecting angle technique can be confusing. How would you explain when to use each technique in a simple way? [00:09:00] Ana Nemec: So given the anatomy of the oral cavity of dogs and cats, it's very simple. We can only use the parallel technique in the caudal aspect of the mandible because we can't really place the film in the mouth in this position. All other standard views should be obtained with bisecting angle technique. Izzie Tsai: When you look at the dental radiograph, what is your usual way of reading it and what structures do you always check? Ana Nemec: The rule we would have in our setting and the way we teach our students is always evaluate radiographs on a tooth by tooth basis and compare with the findings on your dental chart. So always do it simultaneously. It's always your clinical and radiographic part that puts the puzzles together. Then once you're happy with your, as we said before, with your technical quality of the image, you should first start with identifying normal radiographic anatomy. We need to [00:10:00] learn what is normal there. When you start looking at the abnormalities, the first thing is that we look for anatomical or developmental abnormalities, which may not even be pathology. For example, supernumerary roots, fused roots, dilaceration, unerupted teeth. So those are the anatomical developmental findings that may not even be a pathology. Then we move to pathological fix. First is evaluating for periodontal findings, which mainly means looking at the lamina lucida, lamina dura and alveolar bone level. Then it's looking at endodontal findings, which means finding again, lamina lucida and lamina dura, and follow it around the roots, looking for any widening of periodontal ligaments space, especially apically, width of the pulp cavity and potential root fractures. The last category would be other findings, for example, cysts, resorption, fractures, thing that would [00:11:00] classify as other. Izzie Tsai: Which radiographic findings should immediately make general practitioner more concerned or consider referral or different treatment plan? Ana Nemec: Would really depend on how comfortable a general practitioner is with performing different dental procedures. So it's very difficult to answer globally, but to think of a few most common referral cases, for example, non-vital tooth on radiographs, the client would elect endodontic treatment to treat endodontic disease, then probably that's the right case for referral. Then another example would be, we already talked about a dentigerous or odontogenic cyst. If they are super large and we may risk a jaw fracture when managing those, again, probably a case for referral. Any bony changes that are suspicious of neoplasia or like huge osteomyelitis and would require additional imaging, [00:12:00] biopsies, fast staging, those are probably the cases where a team of specialists should be involved. Izzie Tsai: How do dental radiographs help you decide whether a tooth should be saved or extracted? Ana Nemec: So, two most common scenarios that we will see in clinical practice and we have to decide between extracting and saving the tooth are probably periodontitis and endodontic disease. Periodontitis, we have five stages. Zero means healthy. One would mean we would see bleeding of the gingiva, but we won't see any clinical periodontal pockets and on radiographs there will be no bone loss. However, when we start talking about periodontitis, which would mean attachment loss, that would be indicated abnormal clinical findings, as well as radiographically visible bone loss, attachment loss is more than 50%. In those cases, we would recommend extraction. When periodontitis is in clear [00:13:00] stages, we may consider either extraction or periodontal treatments, and that also depends on other factors such as client preferences, general health of the patient, our abilities to treat the tooth, it's not just what we see radiographically in our diagnosis for the tooth. It's also other things that would influence how we treat the tooth and endodontic disease, for example, radiographically if we see severe root resorption due to persistent inflammation, that is more a case for an extraction or advanced endodontic treatments rather than saving the tooth with normal root canal treatment. Izzie Tsai: The guidelines stress the importance of post extraction radiographs. Why are these images so important and what problems can be missed if they are not taken? Ana Nemec: Yeah, the study actually was done by Moore and Niemiec and show that really high number [00:14:00] concerning 82% of dogs and 92% of cats that had previous extractions had signs of a root remnants although clinicians felt that everything went well. Our clinical judgements, and that is what I can definitely confirm from our clinical scenarios as well, you feel that the root is complete and then you take post-op radiographs and you may see remnants of either just cementum or even the whole root piece. In our clinical setting, obtaining post-op radiographs has become a routine because, not only what the studies show, but also what our clinical experience show, that we are very commonly wrong with our clinical judgment of vacating the alveolus. And also what we know from clinical experience as well as studies is that no, if we leave root tips behind, they will not resorb, even worse, it has been shown that most of these retained root tips will show signs of [00:15:00] inflammation, which means that we were extracting the tooth and not removed it completely. We haven't really done anything. Izzie Tsai: And are there situations where dental radiography has limitations in clinical practice? Ana Nemec: Absolutely. We need to understand that dental radiography is an absolute must for indications discussed. For example, if we are dealing with palatal defects, maxillofacial trauma, temporomandibular joint diseases, diseases of the retrobulbar space, oral neoplasia, those are definitely cases where CT MRI, in certain cases also cone beam CT need to be considered. Also, when we have any doubts based on radiographs about our diagnosis, for example, cases ambiguous for periapical lesions, endodontic disease, those cases should also be followed up, or where advanced imaging should be performed, meaning mostly CT or cone [00:16:00] beams. And then if we just touch upon the topic of rabbit and rodent dentistry, cone beam CT and other advanced imaging are basically a must if we want to properly treat these patients nowadays, radiographs will just underestimate the problem because of the superimposition of all of the structures in these species. Izzie Tsai: Okay. How often you use CBCT in your clinical practice? Ana Nemec: So currently we are not really having cone beam CT. We are still relying mostly on CT when we judge that advanced imaging is needed and it's just the fact that we don't yet have the machine. It has been shown in many studies that cone beam CT is superior for diagnosing even periodontitis, especially in brachycephalic breeds of dogs and cats and it's also superior in diagnosing early endodontic disease and it's being considered almost the standard of care, especially in the United States. Izzie Tsai: And finally, [00:17:00] if there is one key message about dental radiography that you want general practitioners and their students to remember, what would they be? Ana Nemec: That brings us to our first introductory question. Take full mouth radiographs routinely, you will become super fast once you are routine in taking those and you will see so much more pathology, which will enable you treat patients much better and for their best. Jim Berry: After Ana Nemec, Izzy Tsai is joined by Jan Bellows for the second part of this discussion. Izzie Tsai: So first question, why do you believe oral and dental disease remains one of the most commonly overlooked problem in small animal practice? Jan Bellows: Well, oral and dental disease is the number one disease in general practice basically because [00:18:00] animals don't brush their own teeth. If you didn't brush your teeth for six months after the dentist cleaned your teeth, or a year, how bad your dental disease would be, and the dental disease winds up being reabsorbed into the body and it's filtered by the kidneys, by the liver, by the brain, by the bacteremia, and it causes problems down the road and it all comes from the fact that most animals do not get any effective preventative care. Izzie Tsai: Yes. They don't brush their teeth. Yeah. Only a small percentage of dental disease is presented by owners as a chief complaint, why are owners so often aware of oral disease in their pets? Jan Bellows: Great question. For two reasons. Number one is that [00:19:00] owners understand that doggy breath or cat breath is normal, so they are expecting to smell bad breath and they get bad breath. When it gets so overwhelming and if the animal sleeps in bed with their owner, then they bring it to the veterinarian for care. The second reason, and probably more important, is that the teeth lie underneath the lips so clients don't even realise that, I mean, they know animals have teeth, but they don't realise that disease is there because they never flip the lips and take a look at the gums. Izzie Tsai: Yes. They also didn't know that pets also needs brushing. Jan Bellows: Right and the whole brushing thing, I mean, it makes great sense, but the reason why it's not done is clients can't figure out what to do with the toothbrush after. Do they put it next to their toothbrush in the bathroom? Do they put it in the drawer [00:20:00] in the kitchen that has a bunch of junk in it? And then they don't know how to brush teeth. Do they brush the inside? Do they brush the outside, in the back and the front? They just cannot figure out how to brush teeth effectively, so in my practice what we use is dental wipes versus toothbrushing. And in cats, Q-tips dipped in tuna water rubbed right at the gum line. Izzie Tsai: Okay. You often say lift the lip. What does this phrase really mean beyond the physical action itself? Jan Bellows: Yeah, so we call flip the lip, which is you just invert the upper lip on the right and left and the front individually and you take a look at where the gums are attached to the teeth and if they're red and swollen and bleeding, I mean, it is time definitely to go to the [00:21:00] veterinarian. Izzie Tsai: Mm-hmm. In a busy general practice, what does a realistic and effective oral examination in unconscious patient actually look like? Jan Bellows: Well, that, that's kind of easy. The veterinarian first looks at the face, looks at the eyes, feels for the lymph nodes underneath the jaw, and also feels for the salivary glands underneath the jaw and there should not be any swelling, and one side should be just what the other side feels like. Then the veterinarian opens up the sides of the mouth. They flip the lips and look at the gums from top and bottom and front, and then the veterinarian opens up the mouth and shuts the mouth and feels for any clicking or arthritis and then they palpate the jaw to see if there's any pain. We also smell the ears [00:22:00] to see if there's any ear infection involved. So kind of anything on the head, the eyes, ears, nose, throat is all for us. If we can look down deep into the throat, that's great. Especially on cats that have stomatitis, we wanna see if there's caudal oral inflammation. Dogs, stomatitis is more rare, but dogs get it too. Izzie Tsai: Okay. And when flip the lip, what early findings should immediately raise concern even if the teeth appear relative clean? Jan Bellows: Well, the teeth could be clean, but because people feed their dogs sometimes unsafe products, like bones or nylon toys, they break their teeth. So one of the big things to alert that there's immediate problems is if the tooth is fractured and you see a dot in the middle that's either red, which means that it's an acute [00:23:00] fracture, or brown or black, which means that it's a chronic fracture, but bacteria is still getting in there. It's time to go to the veterinarian for that. If you see any teeth that have large amounts of gingival recession where you see the roots, that's another reason to go to the veterinarian because the dentin is exposed, which is sensitive to pressure, to cold, to heat, and it's, it, it's painful for the animal, which isn't fair. So you have to go to the veterinarian for any of that. Izzie Tsai: Okay and many vets and owners still focus on calculus. How important is gingival health compared to the amount of calculus present? Jan Bellows: Okay. Calculus and tartar are the same things, and neither of them cause gum disease. What causes gum disease is the plaque that sits on top of the calculus [00:24:00] and the way calculus is created is plaque gets mineralised with calcium and phosphorus in the saliva and turns into calculus. The problem with calculus or tartar is that it's rough. So that accumulates more plaque and then more tartar and more plaque and more tartar and eventually you get what they call anaerobic bacteria underneath the gumline because there's no oxygen there and the anaerobic bacteria are bad bacteria, which eat their way through the periodontal ligament and that decreases the tooth support. Izzie Tsai: Okay and halitosis is often dismissed as normal. How do you explain why bad breath is usually a sign of disease rather than an aging? Jan Bellows: Bad breath comes from periodontal pockets, and if you put your breakfast in your pocket [00:25:00] this morning and you didn't change your pants for the next six months, it would smell and your leg would probably rot off because it would go through the fabric, and that's what happened with periodontal pockets. They fill with food and they get deeper, and eventually it becomes what they call putridification. So it really smells bad. So if your pet's breaths doesn't smell like roses, it's time to see your veterinarian. Izzie Tsai: Okay and why is visual inspection alone so misleading when it comes to periodontitis? Jan Bellows: So below the gumline is where the disease occurs. So the crown could look totally normal, but below the gum line, that's where the pockets are and you just can't see them. Izzie Tsai: Okay. So we need to take X-ray? Jan Bellows: Yes and you need to probe. Izzie Tsai: Mm-hmm. Jan Bellows: Probe six times [00:26:00] around each tooth. Izzie Tsai: Yes and the WSAVA dental guidelines emphasis that a completely oral exam requires general anaesthesia. Why is anaesthesia so essential? Jan Bellows: Anaesthesia is a must because part of the examination must include intraoral radiographs, which must be done with anaesthesia and probing, which can be uncomfortable if the animal is awake. So on evaluation, general anaesthesia with intubation must be performed. Izzie Tsai: And in your veterinary dentistry hacks, you mentioned using something simple, a cell phone, to help with the oral exam in the exam room. I really like this idea. Could you talk about how this approach works in daily [00:27:00] practice and why is so useful? Jan Bellows: Yeah. Well, clients don't really realise what's going on underneath the lips, and they have really, most of them never flipped the lips. What we do in every exam is we flip the lips, show the teeth, show the gingiva and then take a picture of it. Because even if you show a client in the exam room what the problem is, by the time they get home and they share that information with their significant others, the, the message just doesn't ring true because the animal's eating and everybody thinks that everything's fine. But once they see the picture with inflamed gums, with gingival recession, with roots exposed, they're going to be motivated to take care of that, to get the teeth cleaned, to extract the teeth that need to be extracted because they don't have adequate [00:28:00] support and the picture is literally worth a thousand words, if not more. Izzie Tsai: So you will let the owner take the picture home? Jan Bellows: Yes. Yep. Izzie Tsai: Okay. Jan Bellows: That, and we usually email it to them also, so. Izzie Tsai: Oh, okay. Jan Bellows: They get it both ways and it's very easy. We take the picture with our smartphone, we print out the picture wirelessly into our colour printer, and also attach that picture to the client's record. Izzie Tsai: Okay and finally, how does early detection through routine oral exam impact animal welfare and the role of general practitioners? Jan Bellows: Well, generally the animals, if, if they, they, they pass away from either a bad heart or bad kidney disease. That's probably the most common reason why animals eventually die and by taking care of the [00:29:00] mouth adequately and wiping the teeth twice a day, once or twice a day, and giving them VOHC treats and water additives and diets and chews, actually all of them together, one thing doesn't solve it all, but the more you add on, the better. All that will decrease the amount of plaque on the teeth, the amount of inflammation, and I feel they'll live a lot longer and certainly a lot happier. Izzie Tsai: Okay. And one more question. Owner always ask about dry food is best? Or the soft food, canned food or soft food is best? What's your suggestion? Jan Bellows: I mean, it would kind of make sense that dry food would be better because it would take off some of the plaque, but the research has not shown that. The dental diets are definitely better because they work mechanically and many of them also [00:30:00] work chemically through polyphosphates and through sodium hexametaphosphate that's incorporated or sprayed on the food. The clients should check their diets to see if they have a dental diet insignia which could mean that there are additives on there, but diet alone, between dry and wet, doesn't matter. Jim Berry: Thanks for joining us on the WSAVA podcast, where we are transforming care one episode at a time. We hope today's discussion was helpful, wherever you are in the world. You'll find more information and further resources on the topics discussed in the show notes and we look forward to sharing our next conversation with you very soon.