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…My staff has to be on board. I want them with their legs outside that part, and they're all pushing, and I'm pulling and pushing, and we're all flying down with great momentum…

Welcome to the Ruddle Show. I'm Lisette and this is my dad Cliff Ruddle.

How you doing?

Pretty good. How about you?

Well, I'm doing just excellent. I hope our audience, wherever you might be, I hope you're doing just perfect, too, and it's time to learn.

Okay. We thought we would start off this show talking about the patient's perspective. So, you might think your office is inviting to patients and you think it's a pleasant place to be, but what do patients actually see when they're in your office, and how does your staff make them feel?

Well, you recently had the opportunity to be a patient yourself in a dental office. Back in June, you were a patient of Dr. Cherilyn Sheets in Newport Beach, and she's a prosthodontist there. So why don't you tell us about your experience there? How was it?

Well, you're talking about my experience as a patient, aren't you?

Yes. I was actually thinking about my experience and learning about Perimetrics, an interview which I want you all to go Google, Perimetrics—well, you know what? I don't remember much about the visit because I lost my neural access code.

Okay. So, he doesn't really remember, but that's fine because it so happens that he told me all about his office visit right after your visit.

Oh!

And you told me about it on a podcast. So, this might be a really good time for us to show you a clip from one of our podcasts, because not only we see what our podcasts are like, but then you can also get a very fresh patient perspective.

You are sneaky.

So let's watch it.

[Podcast Starts]

And it was remarkable because I had done a road trip down there, and when I arrived, I had to go to the bathroom so bad, I was about ready to wet my pants. I guess I’m 76 or whatever, but I thought I could make it. So, when I got there I wanted to be nice because this is Cherilyn Sheets’ office. And most people don’t know this, but at her front desk there was like four or five ladies. And I go hi! And they go that’s Cliff! And I said where’s the bathroom? And so, I zoomed right down.

Anyway, what I noticed when I walked in... Everybody looked up. And you could say well, they were maybe expecting you. But I wasn’t expected at a certain time; it was kind of a loose deal. So, I thought, I was acknowledged and so was Phyllis. They immediately wanted to – oh hi! So, it’s really important because you’ve heard me say this a lot. People never remember; ever will they remember what you say. They will always remember how you made them feel. So, I felt like a million dollars getting to the bathroom.

So, then I’m taken into a room, and there’s a guy comes in, and he’s been with Cherilyn Sheets for 12 or 15 years, long time guy. Came right out of high school and he was like a real smart kid. He’s like a fixit; he would remind you of Isaac. He could fix anything in the office. In fact, he’s their tech guy.

So now he’s going to do a facebow transfer, and he sticks these things in my ears. But I’m looking around the operatory – I went to this operatory for the facebow transfer. Clean, neat, hardwood floors, view out to the ocean. Okay, you don’t have a view to the ocean in every office, but I’m just saying, these are things that make people feel lighter and happier. Because if it’s all dark and dungy and you can’t see out, you start to – you want to breathe. So I liked the view, I liked the cleanliness, and he told me everything he was going to do before he did it. So even when he was jamming the things into my ears, I was aware it was coming in.

So, we got that all done, then we went to another room, and there was a woman that comes in and she’s taking impressions. And she’s delightful; she’s so excited I’m there; I’m like the only patient they’ve ever had in their life. That’s how you feel.

They made you feel really important?

Yeah, there were no other patients in the practice. Next day, day before, next week, it was just Ruddle. Ruddle is the only – so that’s how they made me feel.

So, there’s a lot of conversation. I noticed she was just like my assistant. If you don’t know what to say, must speak, ask a question. So, he’s asking me lots of questions; you got kids, got grandkids? Well we had connections and we had a little relationship going by the time Cherilyn came in.

Then when I had the new test on the interview – which is a piece of technology I’m not going to go into now – they said actually your wife will run this test. I want to show you how easy it is. So Phyllis was banging – like the little rod hits the tooth, boom, boom, boom. And it’s going into a database, it’s a form, and it’s tapping into AI that looks at all the graphs that come from all these tap-tap-taps. And they’re looking at my graphs and matching up. Anyway, Phyllis got very good at it, and I could tell just in the time she was doing it, there was some insecurity on the first couple teeth. And then when she kind of got more used to it – she was just kind marching right along. And then I hear the praise coming, and that’s another thing staff should do; praising each other, praising the other person. And that makes the patient feel like wow; something good’s happening here. Test another one, what the Hell!

The staff members were high-fiving each other?

They were I think they were high-fiving. And then they were giving me a little Kleenex, and you can rinse out. But I noticed – like I don’t have a spittoon; I didn’t want a spittoon. I thought a spittoon was almost like having a toilet by somebody’s face. Arrrr – well spit.

Anyway, it was in a general practice where they do a lot of spitting I guess. They do a different kind of dentistry. But I noticed everything was clean, bright, happy, constant talking; I was never left alone. You know when they all just about knock the door down trying to all get out of the operatory, and you’re there and you’re like now what? What’s going to happen?

What’s in those drawers over there?

Yeah, and when will that happen? Will it be in my lifetime, or will it be like tomorrow, or maybe later? So everything – the communication, the facility, the cleanliness; the technology was very impressive. I learned – I didn’t know what a lot of this stuff was because we don’t use it in endo. But I was very impressed, so I started asking about everything because I’m curious. I was even opening drawers at the end; I was like what do you keep in here?

A lot of times nowadays you fill out the forms online before you go into the office. So, I would say your website is probably patients are paying more attention to that than in the past. So, you might want to have a nice website—

[End Podcast]

Okay, well that was a nice little clip from our podcast. Would you say that you give Cherilyn's office a five-star review?

Well, first I'd say you're pretty sneaky working that in, a clip I'd forgotten. But back to Cherilyn, yes it was a five-star event, Cherilyn and let's keep it that way.

Did you have anything you wanted to add?

Yeah, three things. The people were impressive, the environment was outstanding, the technology was 21st Century.

Okay. Well, definitely check out our other podcasts and subscribe to Ruddle Plus to have access to all kinds of exclusive content. And if Ruddle Plus hasn't launched yet by the time this show airs, that’s--it will be launching imminently, so keep watching for it. All right, well we have a great show for you today and we have a guest presentation, which you'll see in a minute.

Okay.

Today we have a guest presentation which you will see momentarily. It is by Dr. David Landwehr who is an endodontist from McFarland, Wisconsin. But besides being a leader in endodontic treatment, he also received a degree in oral and maxillofacial pathology. So, he has lectured internationally and presented case studies in both endodontics and oral pathology.

Very impressive.

Today we're gonna see his presentation on advanced endodontic diagnosis, and it's called “The Pulp May Not Be the Problem.” But first, why don't you tell us how you know Dr. David Landwehr and how it came about that we're showing this presentation today.

Well, first, I'm just delighted, David, that you were able to join us today. And I've known David for a few decades. And, you know, we've met first in an opinion leader meeting, and we were one of the crowd, him and I. And then there was many other meetings I ran into him. Now throw in some, we get to know each other more. So, we're together at more meetings, there's some international dinners, nice boat ride in Switzerland, huh David, you remember that to the castle? So anyway, really fun things. And you know, over time, you got kids, you play ball, you do this, you do that. And you start to have a pretty good relationship. So, he was a person I logically thought, you know, he needs to be on the show and I thought he would be lecturing on stationary intraoral tomosynthesis. Let me say that again, stationary intraoral tomosynthesis.

So, that's what I thought he'd do. We had Tyndall, Professor Tyndall, and he talked about more from the physics of it and the applications of it, the science, the millisieverts and all that, but I thought, David, he's a clinician, you know, he's going to show us if he can see these things earlier and pick them off like radiolucencies, incipient lesions with this new technology.

So, I approached him, I said, would you like to talk about tomosynthesis? And he said, well Cliff, I'd really like to talk about jawbone radiolucencies because it's not always the pulp, Cliff. And I said, oh, that would be great. So, we kind of made a handshake agreement, you know, that perhaps he would come back on another show and we'd get to see the technology.

When you see this lecture, you're gonna remember over his shoulder, you saw a portrait, right? That's the tomosynthesis that we're talking about. So, that was kind of it, how it all came down. So, here he is today. And of course, you know, he's wearing blue. So, David, your favorite team, the Dodgers, you bleed blue. I see you have a blue shirt on. Everything's gonna be okay and they're in first place.

Yes, they're doing actually quite well.

Yeah.

All right. So, just to tell you a little bit about Dr. Landwehr. I mentioned he's a leader in endodontics, but he's also maintained a private practice for more than 20 years. He's an educator and also a key opinion leader for Dentsply Sirona. He received his endodontics degree from the University of Michigan, and then he also got the oral and maxillofacial pathology degree from Ohio State University. And Dr. Landwehr was Chief of Endodontics for the Meriter Hospital General Practice Residency Program for 10 years, 2005 to 2015. And he has, in addition to lecturing internationally, he has also published several peer-reviewed articles and he wrote a chapter called, “Lesions that Mimic Endodontic Pathosis” and that chapter is in the latest edition of Cohen's Pathways of the Pulp. So, we are very honored to have the opportunity to show you his presentation today. Let's see it.

[Presentation Begins]

Huge thanks to Cliff for the opportunity to speak to you today and be a part of The Ruddle Show. I have long considered Cliff to be both a mentor and a friend, and I consider it a really, really big honor to be invited to spend a few minutes of my day today with you talking about advanced endodontic diagnosis, because it's important to remember that every radiolucency we encounter is not necessarily of endodontic origin and sometimes the pulp may not be the problem. Treating a patient in a pain-free way to relieve a toothache, it's a really powerful tool and it's a great practice builder for me as a clinical endodontist. But the ability to make a timely diagnosis of a more serious issue can be a life-changing experience for both the patient and the clinician because the consequences are just so much greater. We just can't afford to get any of these things wrong.

So, before I go into the diagnostic aspects of this, I want to remind you that I'm a clinician. I'm a full-time endodontist. Here you see me looking through the microscope, always in search of endodontic excellence. And I show these cases because I want to remind you I have bias. I'm an endodontist. I have endodontic bias.

When a patient is in my office and they're referred to me, it's because someone thinks this is likely an endodontic problem. And in these instances when it's not an endodontic problem, I need to be able to remove that from the diagnostic equation so that I can draw accurate conclusions.

For example, if we look at tooth number 18, I'm guessing I can influence decision-making by telling you more about the tooth. So the real question, is there a periapical radiolucency? And I can influence some of that decision making for you by telling you more about the tooth. For example, if this tooth is asymptomatic with no history of pain, normal pulp testing, and we have several radiographs over a period of time showing no change, I'm guessing that I might influence you into thinking, yeah, this is not a periapical radiolucency. But if I told you that the tooth was symptomatic, non-responsive to pulp testing, painful to percussion, localized swelling, I'm guessing that many of you, if you didn't think it was abnormal, would change your mind and indeed think this is apical periodontitis.

Okay. So, the bottom line is we'll use pulp testing, we'll let pulp testing influence whether or not we think there's a radiolucency. And I really want to get you away from that concept, if I can, because if we only look at this in the endodontic vacuum, then we're forgetting about all of those other potential pathologies that can present in this area that are not influenced by the health of the dental pulp.

So, for those of you that are wondering this tooth number 18 was indeed asymptomatic and normally responsive, so I don't see a radiolucency there. Okay? But now if we look at two other examples, tooth number 13 on the left side image hyper responsive to a cold stimulus, sensitive to percussion, patient has pain. So, this is sort of the classic symptomatic irreversible pulpitis. If we look at tooth number 13 on the right, a similar presentation, sensitive to percussion and palpation, the pulp testing was a little bit vague, the periodontal ligament space is symmetrically widened, and this is actually an osteosarcoma.

So, this is a very significant disease that in this clinical presentation very closely mimics a pulpal presentation. Okay? So, the bottom line is anything can happen in anyone at any time. So, we have to consider some of these other possibilities. Again, the pulp isn't always the problem.

So, as I look at these lesions radiographically and I come up with a differential diagnosis, what I'm really thinking about are all of the things that are possible in the area. No one is expected to know exactly what these things represent and there's no way to know what they represent without a biopsy in most instances. But what are the possibilities?

So, I think about a metabolic possibility, infectious diseases, neoplastic possibilities, developmental lesions. And when we think about neoplastic things, what are the embryological things in the area? Well, we've got endogenic epithelium, we've got nerves, blood vessels, arteries, veins, smooth muscle, glandular elements. There's all sorts of possibilities and remember, anything can happen in anyone at any time.

So, we don't need to know what these radiolucencies necessarily represent, but what do we need to recognize? We need to recognize what isn't normal, right? And then once we recognize that something isn't normal, that this isn't behaving the way we want it to, that it's not a pulpal problem, then we need to think about doing something else. And what is that something else?

Well, that something else might be follow-up. That something else might be referral to an oral surgeon or an ENT. It just sort of depends on what you think the problem might be. Okay, so to help you decide what to do as you encounter these radiolucencies, I'm going to introduce you to a systematic method to evaluate periapical radiolucencies and think about the presentation in a systematic way to help you determine a differential diagnosis.

So, the first question that I'm going to ask is, is this radiolucency multilocular? If the radiolucency is multilocular, I immediately know that it's highly unlikely that it's going to be a pulp problem because pulpal issues, lesions of inflammatory origin because of a necrotic pulp, don't have multilocular growth potential. Okay? So if it's a multilocular radiolucency, I'm going to think about odontogenic keratocyst, ameloblastoma, central giant cell lesion. These would be the most common, even though they're still relatively uncommon compared to a pulpal problem.

But for those of you that trained in dental school or younger clinicians, you might have learned from 2005 to 2017 that odontogenic keratosis was actually termed keratocystic odontogenic tumor, but in 2017, the World Health Organization re-evaluated that. Now it's known as odontogenic keratosis again, so there's been a little bit of change in nomenclature there. It doesn't really matter. The bottom line is you're not going to be able to diagnose it definitively from a radiograph anyway, but this would be the differential. These would be the things to think about.

So, here's an example of a central giant cell lesion actually in a young individual, an axial view of a medical CT. And as we slice through this, you can see a couple of arrows that I've put in there. You can see how thin the lingual cortical plate is on the bottom arrow and on the upper left arrow. The extension of the lesion across the midline. And you can really appreciate that multilocular growth potential.

As we look at this in a more static way, on a panoramic image, I put a couple of arrows in so that you can see the full extent of the lesion and ultimately, after the resection and the necessary endodontic treatment, we can see the end result. So, a central giant cell lesion where the patient really turned the corner and healed very, very nicely, but we can see significant disease crossing the midline.

After determining if the lesion is multilocular, my next consideration is the lesion isolated or multifocal? Patients can have more than a single tooth with a periapical lesion of pulpal origin, but the dental history and clinical symptoms really need to correlate. If a multifocal lesion is present and pulp testing doesn't correlate with the clinical symptoms, then I'm going to have concern about some other potential pathology.

So, the most common multifocal pathology to consider is going to be periapical cemento-osseous dysplasia. This is going to be by far and away the most common multifocal lesion that we encounter, most often discovered in African American females, late 30s, early 40s. The lesion goes through a progression from purely radiolucent to mixed radiolucent, radiopaque, more radiopaque later on. And again, a multifocal presentation not limited to, but most often found in the mandibular anterior region.

So, here we see an example of this periapical cemento-osseous dysplasia in a late 30s African American female and another example of periapical cemento-osseous dysplasia, but in a 30 year old white male. So again, illustrating that these lesions don't read the textbook. Anything can happen in anyone at any time, but again, the most common multifocal presentation is going to be periapical cemento-osseous dysplasia.

And then after considering is it single or multiple, my next consideration is going to be to determine if this lesion is mixed or radiopaque or purely radiolucent. Of course, radiolucencies, as we're talking about the differential diagnosis, should be purely radiolucent. So, if I see any evidence of radiopacity, then I'm gonna think about the potential for a non-pulpal cause.

Of course, the exception to this rule would be condensing osteitis. Condensing osteitis can occur at a root apex, like we see here, subsequent to either caries or a deep restorative history, and that condensing osteitis may regress in about 85% of cases following removal of the inflammatory etiology and occurs most commonly in children, young adults, mandibular molar region.

So, this is a really classic example of condensing osteitis, which we would contrast here with idiopathic osteosclerosis, which is just purely a dense bone island for a reason that we don't really recognize or understand. So, it happens in about 5% of cases, starts in the early second decade, maybe slowly grows as the patient grows and develops, and then basically just sits there. It's static. It doesn't really change with time.

Another radiopacity I'd like to talk about is a pseudocyst of the maxillary sinus. If we look at tooth number two, tooth number two is non-responsive to a thermal stimulus. It is sensitive to percussion. Radiographically, it's sort of unremarkable. There's superimposition of the sinus over the palatal root, and it's very difficult to distinguish if there is any periapical inflammatory change. However, if we contrast that with the sagittal view of a cone beam image, we can see a homogeneous, dome-shaped elevation into the maxillary sinus consistent with maxillary sinusitis of endodontic origin. So, here we have a necrotic pulp that's impacting the health of the sinus and in this scenario, endodontic treatment would be very appropriate.

Finally I'm going to look at the definition of the lesion. I've looked at all of these other aspects and periapical inflammatory disease is going to have an ill-defined presentation or a well-defined presentation and as a result, you might ask the question why make the distinction? So, I make the distinction because ill-defined radiolucencies are also associated with really significant pathology in some instances if the pulp isn't the problem.

So, if the pulp testing and clinical behavior don't meet my expectations, my level of concern for a more significant pathology is going to be increased when that radiolucency is ill-defined. So, the most common ill-defined radiolucencies include periapical granuloma and periapical cysts. So yes, they are the most common and that said, there are also many ill-defined radiolucencies that are going to be of significantly greater clinical significance.

So, here's a tooth number 30 that I treated endodontically without complication. There were no issues at the time of treatment, but she returned to my office just over a year later with very significant bone destruction around 30, around 29, around 28. There was significant mobility, soft tissue involvement, so this represented a relatively aggressive, but localized osteomyelitis. Ultimately those teeth were extracted and she did very, very well from a healing perspective, but never opted to have anything put back together. So, significant localized infection.

And then, of course, there's drug-related osteonecrosis of the jaw. Bisphosphonates originally were reported to be the cause, but now we see all sorts of other drug classes that are implicated in drug-related osteonecrosis of the jaw. So, we will get a list into the show notes for Cliff of all of the medications that fit under these categories so that you can use that in your clinical practice.

So again, the concern with ill-defined radiolucencies is that this differential is so ominous. So, we see osteosarcoma, Ewing’s sarcoma, lymphomas, metastatic tumors, multiple myeloma. So, lots of really, really bad disease that presents with an ill-defined radiolucency.

Here's an example of metastatic prostate cancer. And another example of a lymphoma at the root apex of tooth number eight. This tooth has a deep restorative history. The pulp testing may not be conclusive. Radiographically, the lesion is ill-defined. This very closely mimics periapical inflammatory disease or something that I might see in my clinical practice on almost a daily basis. Of course, I don't see a lymphoma on a daily basis, but periapical inflammatory disease. And these things look very, very similar in this clinical presentation.

So, after we have all of these other things considered, we're gonna run into unilocular, well-defined, isolated radiolucencies. That's sort of our bread and butter, right? Most of the periapical cysts and periapical granulomas that we encounter of inflammatory origin, pulpal problems, are going to be unilocular radiolucencies.

So, we see tooth number 30, non-responsive to a thermal stimulus, a widened ligament space and lesion at the mesial root apex. So, not reinventing the wheel here, this is periapical inflammatory disease and it would then be very appropriate to think about root canal treatment. And here we see a healing area six months down the road.

So, the differential diagnosis of unilocular radiolucencies in other positions because they don't all occur at the apex, right? They can occur at different spots. We see, in this instance, a sort of multilocular presentation. Tooth number five was non-responsive to pulp testing. But because of the multilocular nature, I didn't feel this was periapical inflammatory disease. And the patient was referred for further evaluation. Ultimately, a biopsy was done and this proved to be an odontogenic keratocyst.

And here we see a unilocular radiolucency between the premolar and canine and that would represent in many instances a lateral periodontal cyst, but in this instance, it's actually an ameloblastoma. So again, anything can happen in any one at any time. These things don't all read the textbook and some of these lesions will look very, very similar radiographically, so really it becomes a matter of biopsy to be able to make the definitive diagnosis.

So, what can we conclude from all of this? Again, a multilocular radiolucency should not be the result of a necrotic pulp. So, if I see a multilocular presentation, I'm going to consider immediate referral. Most radiographic lesions of inflammatory origin are going to be radiolucent, and as a result if I see calcification, I'm going to be concerned about a non-pulpal etiology. We talked about a couple of exceptions, but really for the most part, anything where I see any level of radiopacity, I'm going to think about something that may not be pulpal in origin.

A multifocal presentation should also arouse suspicion about a non-inflammatory etiology, especially if the dental history and the pulp testing are not consistent with pulp necrosis in multiple teeth. Periapical inflammatory disease can be well-defined or ill-defined, and when the radiographic change is confined to the medullary spaces, we may not be able to see much of a lesion at all with periapical imaging.

However, if we see rapid cortical expansion, perforation of the cortical plate, extensive tooth mobility, root resorption, a moth-eaten appearance, something that suggests a more ominous differential, these cases should definitely be referred for further evaluation to the specialist that you feel most comfortable with.

For clinicians, it's important to remember that the great majority of abnormalities we encounter on a daily basis are going to be due to a bacterial etiology, the result of a necrotic pulp. However, it's also really, really important to remember that developmental metabolic neoplastic etiologies can resemble the inflammatory cause as well.

So, this discussion today was really a very brief overview. I attempted to categorize a few lesions based on the most typical radiographic presentation encountered in clinical practice, but many of these pathologies are not going to fall into this classic classification scheme. A single category may exhibit a wide variety of radiographic appearances. We also focused on what are by far and away the most common non-inflammatory lesions. This is a very brief overview and not a comprehensive review by any imagination.

So, I am going to ask the question, do the pieces of the diagnostic puzzle correlate? How does the medical history fit with the dental history and the clinical findings? And I'm simply going to ask a question, do the pieces of the diagnostic puzzle fit together? And if they fit together and it's saying this is an endodontic problem, great. Then I think it's really appropriate to consider endodontic treatment. But if the pieces of the diagnostic puzzle don't fit together, and I see something that is looking more ominous, something where we do see an atypical presentation, then I'm definitely going to be considering biopsy and referral.

So, I hope this quick overview gave you some information about these common radiographic changes that are gonna help you in your day-to-day diagnostic workflow. Because I know for me as a clinician, a diagnostic dilemma is basically a huge roadblock and my day comes to a screeching halt, okay?

So, today we focused on periapical imaging with some CBCTs. I'm looking forward to a return visit to The Ruddle Show. I've already talked to Cliff about this, so I hope to get invited back to talk to you about some emerging imaging technology that I'm using in my clinical practice called stationary intraoral tomosynthesis. And I'm really keen to see what it might do for my ability to detect some of these lesions that we've talked about today and formulate a differential diagnosis. But that's going to be a different discussion for a different day.

So, with that I really want to thank you for taking some time with me today and again, a huge thanks to Cliff for all you do for The Ruddle Show and in advancing health care worldwide. So again, many, many thanks for your time today, and I hope this was a beneficial experience. Thank you.

[End Presentation]

All right. Well, that was a great presentation, very clear and organized. And Dr. Landwehr seems very professional and friendly. And I really liked, I thought he did a really good job both explaining and showing the differences between an endodontic problem and a problem of more serious pathology. I personally had to look up a lot of words, and I had to pause a lot and look up a lot of words, because although I am familiar with a lot of the endodontic terminology, I'm not so familiar with the language of oral pathology. So, anyway that's just me, but what did you think about the presentation?

This is why I want to introduce our audience to my little Bible. And this book is very clever because the first part of it's just green, and this just gives you all the lesions and all their characteristics. And then you have a page number and you go to white pages and you can see pictures and everything. So, this is what I had in dental school and I swear to God that Bhaskar and Landwehr wrote this. I didn't see Landwehr and I was looking all over and I'm still looking. I'm sure he was a co-author.

Anyway, I thought it was really good how he took a complex issue that most of us—let’s be honest out there, most of you dentists out there, you know, you have a glimpse of everything, but when you hear David, I like how he took jawbone lesions, radiolucencies, and he divided them into metabolic, infectious, neoplastic, and finally developmental. So, that already put all these lesions, because there's hundreds of different variations, into four buckets, and then there's similarities within the buckets of how you might treat or the patient might respond. So, I like that.

He really stressed the importance of the diagnostic puzzle and I thought that was very, very cool. There's a lot of things that we reach for, sometimes to rule something out. We don't know what it is yet, but at least it's not that. But he really talked about assembling the puzzle and the puzzle was really comprehensive medical histories, dental histories, and of course the dental history would be big emphasis on your endodontic examination and that would include vital pulp testing, clinical findings, and imaging.

So, fabulous job and then the tagline, David, anything can happen to anyone at any time. We've been both laughing about that and of course everything that happens from a hangnail now to a slip and fall is anything can happen to anyone at any time.

All right, well you pointed out some things to look for that may indicate a problem with more serious pathology. For example, watch for multilocular radiolucencies. Is the radiolucency isolated or multifocal? Is it ill-defined? Is it radiopaque? It seems that vital pulp testing, or pulpal sensibility testing if you prefer, is key to being able to accurately diagnose the problem, correct?

Oh yeah. We all see lucencies all the time, and especially when they're associated with the apices of roots or lateral to roots or in the furcations of roots, wow, we really need to know how to roll up our sleeves and do the whole examination.

So, I really want to stress the vital pulp testing, or as you said, the preferred term now is sensibility testing. But that would be determining if the pulp is necrotic or vital. And of course, there's different ways we can determine that with our testing, but you're trying to connect what you see on the image, a radiolucency, and you're trying to find the culprit, the etiology. And if it's a tooth, you're right at home, you feel good about that, that's what you learned in school. That's the preponderance of them. That's the preponderance is they're gonna be endodontic in origin.

But I'll let you go ahead, but that's kinda what I liked about what he did. In the vital pulp testing, just come back and stress, get a baseline, please. This is a patient with a radiolucency, they got a problem. And don't assume, ah, hold on, it's an endodontic problem. It could be something very serious, even life threatening.

So, baseline, that means you test contralateral teeth, opposing teeth, adjacent teeth, to the one that might be in the area of suspicion. So, really good at the baseline. And once you have baseline hand signals, and we've done shows on all that, then you can either start ruling out the tooth or rule it in. So, if the tooth is vital and kind of boring, normal limits, hand goes down after a few seconds as compared to contralateral opposing adjacent teeth, then you're thinking, this is a pretty healthy tooth. The lesion isn't necessarily associated with this tooth. It might be something else.

And so, I think we really need to stress to everybody out there, if more than one person is responsible for a miscalculation, no one's at fault. What does that mean? That means refer to an oral pathologist. If you're in a big city and there's a dental school, there's one there. They're not in every hamlet or city or town, but oral pathology, maxillofacial surgeons, endodontists, we do see these things and like David, very few are as learned as David in oral pathology, but many endodontists know quite a bit about it, and that's the place you should be going to, is people that can help share the responsibility to best serve the patient.

Okay. Well, one big question I had when I was watching the presentation was how often do endodontists encounter these types of more serious pathologies that Dr. Landwehr was talking about? Because I was thinking if I was a clinician, and especially if I was a new clinician, I'd be pretty concerned that I might miss a really important diagnosis. Because not only is the patient's health at risk, and then of course liability, but I just want to be able to sleep at night and know that I'm not putting someone's life in danger and missing really important diagnoses. So, when you were practicing, how often did you encounter these more serious pathologies?

You know, I'm going to tell you two things. Personally, I would think I was finding something. I did a little bit of reflection on this because when you said that question, it sounds easy. Oh, five a year, 10 a year, 20 a year, one a month, not every day. But it turns out, I might have saw two or three cases a year that weren't in my domain, endodontics. So, it doesn't sound like very much, does it? You know, you see maybe a thousand patients a year, four days a week, blah, blah, blah. You do the numbers, you might see that. But I found an article in the Journal of Clinical and Experimental Dentistry, 2021, I believe. And I was kind of sober.

So, they looked at about 1,500 patients, a little bit more, but more or less 1,500. And they diagnosed them as teeth that were diagnosed with periapical endodontic lesions. And then they did over about 10 years or a little longer, they began to follow those, and they even did histopathological, that means biopsies. They found out that 10% of what appeared to be endodontic lesions at apices of teeth were not lesions of endodontic origin, they were something else. And of course the most common one was the dentigerous cyst or the odontogenic keratocyst. Those are very common, they're not serious, but anyway, it was more than I thought.

Well, it does seem like we've talked about AI a lot on our show it seems that this would be a good application for—

Can I stop you? I didn't say this, but we need to really tell our audience, look at those medical histories because of bisphosphonates.

Oh, right.

I forgot to say that. A lot of patients especially people that are like my age, women and men, more women, are on these bisphosphonates and they're because they're getting these meds because of osteoporosis, patches disease, and even cancer.

So, when we see patients on certain kinds of drugs, and when I say bisphosphonates, the show notes are going to have all the kinds of generic drugs you'll see on your medical history, because bisphosphonates is the umbrella. Now, you've got to become familiar with all the generics and the, you know, the label ones, because if people are on it, that can create jaw lesions. So, be careful of the medical histories.

And I wanted to also talk about endodontic lesions, or she already said this, that they're almost always unilocular, and they're not multilocular, and they're more focal, not multifocal. So, those are really important things to come back to our notes to you're trying to decide is it this or that?

Okay. Well, I was just gonna say, before I was so rudely interrupted, no I’m just kidding. I was going to say that it does seem that AI could be really helpful in the future to—

Yeah.

--either identifying a more serious pathology or just ruling it out. It seems like it would be helpful, a good application for AI then.

You know, AI is a big deal. I don't know if I even talked to you about this, but the AAE has been widely marketing on the AA discussion forum about special guest lectures. They have them every now and then. And you—there are maybe two or three time slots for convenience and you can go hear people. The latest one is on AI. So, that's what brought that up and you and I've done quite a few things now on AI, but specifically to this I got so excited because I see all the little applications early. And they're interesting. And you're going okay, it's coming. Like a big train rumbling down the tracks. I hear it, but right now I'm okay.

But boy for AI, think of this, you have a massive computer farm. And you have somebody there that is bringing in all the lesions and now what's missing? We need to know the patient's history. So, you need their medical history, their dental history and that would be the endodontic exam and the tooth’s fine, necrotic and all that. But AI can look at hundreds and hundreds of thousands, if not millions of patients and look at the medical, the dental and the radiographs and you could have something you're going, I'm not really sure what that is. Well, if you punched in all the stuff I just said it would go to this massive farm and of course the machines are learning as they go and you're gonna probably get a differential diagnosis of one or two things. It’s either this or that.

Yeah it does sound promising. Well, I guess in closing, I would like to just say that I used to go to the dentist and just worry about getting cavities. It seems like maybe I have to worry about a lot more.

Well, not really. As grim as oral cancer is, and when you hear that name associated with perhaps yourself, it brings up a lot of emotions. But what we can all do is also take a lot of confidence in that, what is it, 53,000 people a year die of oral cancer, so that's a lot. It's kind of in there with car accidents and different things.

Well, actually I thought there was 53,000 cases of oral cancer a year, maybe not all those people die of it.

Good distinction so there's 53,000 cases of oral cancer but we have a population of what 330 million. So, if you do the math it's less than 0.02, I'll say it different, two hundredths of one percent have oral cancer in the United States.

And that’s in the US, yeah. Okay. Well, thank you again to Dr. Landwehr for that great presentation.

Yeah and David thanks a lot pal and I'll have to have you back for that stationary intraoral tomography. I mean, geez, and then of course, David, Go Blue! Dog days of August are just over now; we're in the stretch drive; it's September everybody; tighten up, here comes the Ruddle Show with David.

Okay. we wanted to close our show today talking about the psychology of endo and the importance of having a positive mindset, especially when confronted with obstacles because it's easy to have a positive mindset when everything is going well.

Yeah.

You are feeling confident you are finding all of the canals you are getting to length effortlessly but how do you respond when things don't go well? When mishaps occur, do you snap at your staff? Do you beat yourself up internally or do you just walk around looking really down and dejected? Well, your internal conversation is very important to your perception of reality, correct?

Yeah, I'd sure like to be your patient if you had just blocked and you're walking into my room. See all that dejected body language? Well, I think I'm gonna deviate a little bit from your expected answer, maybe even you won't expect this, but in the 70s there was a prolific tennis player and coach and his name was Timothy Galloway. And he wrote the book, The Inner Game of Tennis. And I had come into contact with that audio many, many years ago. And I share it with some people in the family, so I don't know if you've ever heard it.

But he talks about there's two games going on in any one tennis match. There's two games. There's the stadium, there's the court, which surfaces it, and there's the players, and there's a scoreboard, and there's an umpire, and I mean, everybody can see all this. That's the outer game. And the course scores are kept in the outer game.

But what most people don't think about is during play, there's an inner game. And the inner game oftentimes, as you said, when things are going well and you're lashing your backhand, the overhead is just flawless today and the ground strokes are coming along, but what happens when you know you're behind and it's not going well maybe there's unforced errors?

Think of endodontics, the operatory, the patient and their tooth. That is the arena and you're competing against the tooth. How long is it? How big are the diameter of the cross-sections as you go down through multi-planar curvature? So, you're competing against that and there's an outcome.

And so, oftentimes in the inner game if we have a little bump in the road like a block or a nuisance block or a serious block, there's a big tendency to access your inner self and start talking about your doubt and your worries and then all of a sudden, there's a receptionist behind you and there's something over here and there's distractions and now you can even go to loathing the game you're playing.

So, I think when I heard that decades ago, I actually was thinking of me practicing the two games, the inner game and the outer game. So, I really think it's important, how you communicate is how it is. And if you think you can, you can. And if you think you can't, you're right. And so which one wins? The one you feed.

Exactly. Okay. So, let's look at an endodontic mishap and discuss maybe the best mindset to resolve the problem. So, say the canal is blocked, and it's severely blocked, by either you or a referring clinician. Like, how do you proceed?

Well, first you probably drop down on your knees and offer up a few prayers to the God you worship, but I don't know. Okay. So, it's a serious block and I think what you have to do is you have to think about--you know, you got to--practice is experience and you can't teach that. So, your experience tells you I get through blocks all the time. So, see I'm trying to change that conversation. And if you did it, of course you're going to have a different conversation than if somebody else did it and now you're sitting there as the specialist trying to get through this block.

You know, we can't use all these words on air but we would be talking about the other referral. We would have many descriptors. But it happens and so, I think you have to not remember what's going on right now. You have to pull from within yourself, that been there, done that, I've seen this before and I will be able to get through this block. And I'll be using some tools. I mean we might use TCA, we might use—well, we talked about this, there's citric acid, but if we put three chlorine molecules on that, we can have a chloroacetic acid, that'd be TCA, and then we could probably think of viscous chelators, RC Prep, like Pro Lube. Is it a 10-file? Is it an 8? Is it a C-file? Is it stainless steels or NiTi? Those are all things we're not going to talk about now, but the mindset is you'll start to gravitate towards those tools and those memories and those experiences that you've had before where you succeeded. And if you keep thinking about the unsuccessful management on your last time, how do you win the next point in tennis if I'm focusing on the point I just lost?

Right, and I've also heard you say to visualize yourself actually bypassing the block.

Oh, do you want to hear that? So, I am--I'm almost embarrassed to say this, I'm on the end of the file and I'm watching my file and I'm seeing it start to penetrate, maybe a collagenous block, a stump of tissue or maybe it's mud, dentine mud, or maybe it's a cocktail of mud and collagen. And I'm seeing the tip of my file, it's starting to penetrate. I’m seeing a little rotation. It’s starting to engage. I don't want to move to a smaller file yet because I got to have some wall support. So, I got to get about two millimeters into that, maybe three would be a perfect world. And now I have the walls of the canal supporting my instrument and I'm watching this instrument and I'm working towards length.

That's kind of what I see and I keep doing that and sometimes I go through mounds of files that the audience has no idea, but when you get to length, you go every one of those babies was so important.

Okay. Well, some words that I've heard you use to describe the mindset that is a good mindset to have when trying to bypass a block. I've heard you say them and I've also seen you write them too in papers and stuff. And those words are determination, patience, and perseverance.

Hm.

And those sound like nice words, but I think that when you really think about what those words mean, at least for me, it helps you kind of internalize them more, and it really just contributes a lot of positivity to your mindset. So, if I think, like, of determination, for me that means you're confident and committed to the task.

Oh, very good.

So, you need determination. Patience for me means like calming down all the negative noise inside of you and focusing on the result you want and how to best achieve it.

No distractions.

Right. And I think, to go back to sports, when they say an athlete is in the zone, to me that means that they're being patient, the game quiets down for them, they see everything, they see the opportunities and how to best get the result they want. For me, patience is very connected to focus because it means that you're not going to react emotionally and that you're going to be adapting and trying to like change.

Make adjustments.

Yeah, adjustments is the word I'm looking for. So, and then there's perseverance. And for me that just implies that it might take some time, right?

Yeah, you might have to like provisionalize, bye-bye, and reschedule. And we know that costs money, doesn't it? So, are you willing to do that because you're treating a patient? Or is it next case please?

Right. Okay. So, why don't you tell us some other strategies you can take to be in a good mindset?

Well, my staff has to be on board, you know, it's not me getting on the harness every day and they jump in the wagon and I pull them forward. I want them with their legs outside that cart and they're all pushing and I'm pulling and pushing and we're all flying down with great momentum. So, I get my staff involved, so probably you wouldn't notice but my staff knows to come aboard and help me. I need a little boost. I need to know the fans are applauding. I just ripped a backhand.

So, they'll say things literally, they'll say things like well--because I'll say you know I've encountered an obstructed canal, it'll just be momentary, will be to daylight. And then they'll maybe say a little bit later well--and then I see that little hand on Mary's shoulder, the patient, they'll say I'll be really surprised if he's not to length within five minutes, that would be very normal around here.

So, it puts a little pressure on, but it brings some urgency, great focus, and when somebody says you'll do it in two or three minutes, by God, you usually do it in two or three minutes. It's amazing how that happens.

The patient feels confident too that you might know what you're doing. If their staff is doing it.

And when you don't make it in two or three you go, oh that's right I was really thinking nine minutes and that's just the first third of the nine, so we're third through.

But be careful because in all this if you're in a curved root and remember the canals are more curved than the roots that hold them and if you're picking away you might want to stop and take a radiograph every now and then. Pull the file out. Wipe off with your ring finger. It's a glove. Just wipe off the viscous key later. And do you see that file starting to track? So, are you making or are you following, and a radiograph will help you see if you're starting to kick into the curve, so you can go around to length. But if you see the straight line and the canal's curve and you pull your instrument out and it strays an arrow. Maybe that's another lecture for another day, but that's starting to make, Cliff's making a canal now not following a pathological or physiological canal.

I think you also sometimes just get up and get a glass of water, tell the patient I'll be right back; I got something in the tooth that's working. It's probably working when I'm there activating what's in there. But anyway, it gives me a chance to maybe talk to somebody or say I'm back behind, I'm fighting this block, but damn it I'm gonna go back and make it happen. So, it's nice to get up sometimes and just reassess, recompose and get back in there.

And then I think finally there's no shame in a referral. As Schilder used to say… “Make yourself the patient and you'll have the answer.” So, if you were in the chair and given your skill and your knowledge and your experience, would you want you to try to get paid?

Okay. Well, I think that we're seeing now that you could really do a lot more with a positive mindset. And this isn't only for endodontics and sports. I think probably we could all benefit from a more positive mindset and talking internally to ourselves more positively regarding many areas of our lives.

That was excellent.

Okay. Well, that's all for today. We'll see you next time on The Ruddle Show.