Could This Type of Dentistry Make Me a Happy Dentist?

In 1995 Dr. David Alleman wanted to quit dentistry. Frustrated with failing restorations and post-operative sensitivity, he couldn’t see how his work was helping his patients. A long-time friend and colleague encouraged him to take a course by Ray Bertolotti to learn about a new type of dentistry: adhesive dentistry. It was then that Dr. Alleman first thought, “maybe this type of dentistry could make me a happy dentist.”

Books referenced in this episode:

• Nobuo Nakabayashi, David H. Pashley. Hybridization of Dental Hard Tissues. Quintessence Publishing Company; 1998.
• Dietschi, Spreafico. Adhesive Metal-Free Restorations. Quintessence Books; 1997.
• Hubert E. Schroeder. Oral Structural Biology. G. Thieme Verlag; 1991.

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Transcript

0:34

Greetings from South Jordan, Utah, and our studio with our directors, Audrey and Hilary. We have a great team. We couldn't do this without the team. I want to give them credit. This is very exciting time to remember for me. This takes me back over 25 years to 1998. I've mentioned in earlier podcast that my whole world was shaken and inspired in 1995 by the possibility that a piece of dentistry could make me a happy dentist. I was an unhappy dentist at that time after 17 years of practice. But in 1995, my first mentor, Ray Bertolotti, introduced me to adhesive dentistry that was coming from Japan. I heard the name Takao Fusayama for the first time. I heard the name of the company Kuraray for the first time, and he gave me a bibliography that gave me the first insight into dental research. 25 articles in 1995, I began a three year process of becoming very familiar with adhesive dentistry. Its concepts and its applications. But there were new concepts that I was learning from the literature review. The next literature review mentor that I had was Gary Unterbrink. I met him in 1998. Ray Bertolotti had mentioned his name and I met him at the convention where I first had lunch with Ray Bertolotti in 1998 at the ADA convention in San Francisco. I flew there after three years of great interest in a piece of dentistry, learning some basic protocols from Ray Bertolotti And now in 1998 I was invited by Dentsply to a pre-convention daylong seminar with many speakers. There I saw Ray Bertolotti I sat next to him and then I had lunch with him. I was very privileged to be there. I didn't know half of the people that were there how important they were. But one that I remember I sat next to is Michael Miller. Michael Miller was the editor of a very important compilation of product information, which was called Reality. And Reality had been published out of Houston with Michael Miller and his wife, Inez. For many years. It's a great compendium on adhesive dentistry. But again, I'm sitting there and I'm listening to many, many speakers. But after the presentations were made and I had lunch with Ray Bertolotti he introduced me to some important names. And one was Charlie Cox. Charlie Cox was speaking at the San Francisco meeting. And so he said, Go listen to Charlie Cox. Go listen to John Kanca III And when I did, I understood that the adhesive dental research that I had been reading had been published in printed under the direction of actual dentists. Some in academics like Charlie Cox, some in private practice. But John Kanca was also involved with the manufacturing company, and that manufacturing company was called Bisco. And Bisco had created a product called All Bond Two, which was basically the best bonding system in 1998. But in that year, the Kuraray system had basically introduced the superior and the gold standard bonding system that would overtake all bond, too. But again, you know, I'm just a dentist trying to figure out how to fix teeth. And my mentor, Ray Bertolotti says, well, go listen to Charlie Cox and go listen to John Kanca III and John Kanca III said there's a prosthodontist on occlusion. John Kois That would be worth listening to all these first names that I'm learning. None was more important than Gary Unterbrink, who actually was working for a manufacturer. And the manufacturer that they were working for had a booth at San Francisco. I went to the booth and met him and talked to him for about an hour and got a pre-publication article that he was publishing the next year in 1998 with Bill Liebenberg. And that article was a real seminal article to put many of the pieces together of the Six lessons approach. But in 1998, at the convention, probably the most important thing was the purchase of two books. Unfortunately, both of them are out of print now, but the hybridization of dental hard tissue by Nobu Nakabayashi and Dave Pashley published in 1998 and adhesive metal free restorations by Didier Dietschi and Roberto Spreafico published in 1998. Now, this book is very technically detailed, but practically nothing in this book is applicable to what we teach today in adhesive dentistry. Now think about that. So for 25 years, this has been one of my favorite books. Why? Because it showed me what are the questions that need to be asked when you're doing adhesive dentistry? The coauthor Nakabayashi. She named the Hybrid Layer 1982. He says We have this interaction between the dentin and these composite resins and their interacting in a interphase is kind of like the DEJ. That's an important insight. That's very useful. But when he started talking about how the bond is strengthened in the hybrid layer, he got diverted by some research projects and some experiments that he did, and he got convinced that bonding to collagen in which is the most easily identified structure in the hybrid layer, was very important. Turns out that's not true. But if somebody gives you a foundation of what question to ask, even if their answers are not right or they need to be improved, it gives you what's called a heuristic advantage. In other words, all of a sudden you're thinking, okay, maybe everybody doesn't have all the answers, but if we can keep working some way together, we can make some progress. Well, this book was a real blessing to me because when I met Nakabayashi 15 years later introduced by Selma Belli at the International Congress of Adhesive Dentistry and Pennsylvania. Actually, that was the second time I met Nakabayashi. The first time was in 2009 at the IADR meeting in Miami Beach. When I had that first conversation with them, it was kind of crowded around, as, you know, couldn't hear really well. But because I was meeting the researcher who named the hybrid layer, it's a great honor. The lecture where I met him at was actually the lecturer was Junji Tagami. He was on the stage. We had a half hour with Tagami He introduced the acid base resistance on super dentin to that group of 400 researchers at IADR, Miami Beach, 2009. But the second time when I met Nakabayashi, we were all by ourselves. He was doing a poster presentation at this IAD meeting and Sema Belli took me downstairs. It reintroduced me to him and I thanked him for all the good research. Thank him for his book that he had published, because this book in the back had what was very valuable pages of references. This is called a bibliography. So why would you go to this bibliography? Well, you'd only go to the bibliography if you understood what science is, how science happens, and how it builds upon itself or gets lost. But once the bibliography is published, this had over 400 references, mostly articles. So each of these references, 400 references represented 12 or 10 to 12 pages. And so all of a sudden you say this is 400 references, it probably as 4000 pages of information that impacts the hybridization of dental hard tissues, adhesive, dentistry. You know, a kid who goes to dental school just wants to make a living being a dentist. He has a dentist friend. His own dentist that has a nice car, takes vacations, has a nice house, seems to be a dream life. The kid gets inspired. I'm know I'm going to be a dentist. Then they go to college and they take histology and they take chemistry and organic chemistry, organic. They do things that are not easy scientifically, but they're just, you know, learning what they need to know to get into this dental school so they can be a dentist, takes teeth, people pay them money and life is good. That's basically how deep most dental students go. They decide to be a dentist. If we have an idea of what a science is, remember, I grew up in a house of a scientist, a physicist. He actually had references, articles, journals that had references every time I'd look at one of these journals like Scientific American, I would always see some references. And then I went to high school. I really had my comeuppance because I got selected to be in the first AP class ever offered at Mark Keppel High School. But I'm in this class and all of a sudden it's a history class, and I get introduced to the fact that we're going to have to write an original term paper. And this original term paper begins with collecting references that we're going to go to the library and we're going to read. And then from those readings, we're going to make deductions. We're going to decide what this other research contributes to our knowledge. And that's how you learn history. So I learned biblical atrophies in a class in high school, and I was in that class for two weeks before I told my good friend Phil Baker. Phil, we got to get out of this class way too hard. So we both dropped out and went into the easy history class to get the easy A and you know, I went on with my life eventually got married, started a family, get into dental school because I want to support the family. And I have good hands. I have good eyes. I have some artistic skill. I'm good with people. Many people said you'd be a good dentist to get into dental school. I had to get an A in organic chemistry, so I did. It had to work hard, but it was science. But the science had a history that goes way back, way back. And these early researchers in organic chemistry had to figure out every molecule. Plus my major was microbiology, so there was interest there. But again, when I get into dentistry, I don't understand how dentistry is a science because nobody talked about any science. All they did was just say, do this, do this, do this. If they gave you a reason, it was a very superficial reason. But I just wanted to graduate from dental school, so I accepted it and learned it. And I had good hands. I could do everything they taught me to do, but I didn't know why I was doing it. And after 17 years, when I quit dentistry out of frustration, I became irony upon irony, which historians love Irony. I decided I would be happy being a historian. So this whole idea of learning something about life through history Now, when I'm introduced to adhesive dentistry in 95 and around 98, I get really inundated by the amount of science that has been done up to 1998. But then I become convinced that it hadn't been done enough and there were still more questions to be answered. And so when I went home and took my two books, I went serious into the dental research, collecting hundreds of articles to read and reading the articles 3 to 5 hours a day. And then when I came to the book by Dietschi, I became aware through the magazine reality because reality, this adhesive compendium, these are not small books, but they're very, very picture oriented. And as you go through and look at every material, every product that is reviewed and some techniques that are reviewed, this is out there. It was a very nice compendium, but when I read them because of the signs that I had already accumulated in those three years, I could see that Michael Miller And Inez Castellanos did not have it all figured out, they didn't have enough science. For example, Ray Bertolotti introduced me to it. He said, dentistry introduced me to hybrid layer, introduced me to Fusayama’s techniques of total etch, and also introduced me the concept of C factor. And as I questioned Ray Bertolotti about C factor, he had some answers, but there were many that were vague. And so three years later, meet Gary Unterbrink he had better answers, and his answers were based on the research that had come out in 1984, 1984 and 1987 from Carol Davidson. And this was the real beginning of understanding C factor, which was very confusing because it was the transition between like cure materials from the chemical cure materials, which is adhesive dentistry, and or Fusayama and others was basically based on chemical cure reactions to get these composites to solidify. Anyway, so I'm talking with Unterbrink and I'm being inspired in the next year from Dietschi and in Reality they list what courses are giving being given around the country. And they had a course in 2000 given at UCLA by Didier Dietschi. I immediately signed up and flew to Los Angeles for two days spent with Didier Dietschi. It had lecture and hands on components. I told Dietschi, I said, I've learned the semi direct technique. It's a real breakthrough. It takes half of the polymerization out of the stress. It could go to the hybrid layer and I really think this semi direct is something every dentist needs to know. That was a huge thing. And then I said, I think you're the best dentist in the world. But what I want to know is who do you think is the best dentist in the world? And Dietschi didn't think very long. He said, I think Urs Belser now. I've been reading dental research for five years. I mean, I knew the names. I'm good with names, you know, that's one of my gifts. I remember names and then Urs Belser did not ring any bells at all, but I found out that he was his mentor, his mentor at University of Geneva, and he was a prosthodontist, an expert in the occlusion, an expert in full mouth reconstructions, an expert in implant placement, an expert in all phases of that specialty prior sardonic. But what I had forgotten, maybe I never read it, is that in the introduction to Dietschi’s book, who wrote the preface? The preface was written by Urs Belser and Urs Belser makes reference to Foundational dentistry, which is usually referred to as operative dentistry or single tooth prosthodontics All of that is usually the mechanism for failure that creates the need for large prosthetic reconstructions. In other words, fillings lead to larger fillings, lead to crowns lead to root canals, failed root canals lead to extractions, implants, all of what we call the cycle of death. If we understand that Urs Belser, who took his two best students Dietschi and after him Pascal Magne and said, You know, I know that you guys have talent, you could do anything you want. But I believe that adhesive dentistry is where you should go because that prevents all these other failures from happening to a large degree, maybe entirely. And so Belser put Dietschi on the path of adhesive dentistry. Obviously, he was a mentor to Pascal, and over the years after these 2000 or he became my mentor in a two day course, I stayed in touch through his literature. His literature review became very detailed. Eventually, his independent research allowed him to write a PhD dissertation for the University of Amsterdam. This paper, by Dietschi came from that 2003 Ph.D. dissertation, which is accepted, and he has a Ph.D. independent research and that re independent research confirmed things like deep margin elevations decoupling with time. All of these concepts were there in 2003, but in the book in 1998, he was doing deep margin elevations with amalgam as the best he had. Later that year, he published an article that corrected that to a certain degree. It's a long story, but the bottom line is that we've had contact over the years last year, Davey and I had the privilege of speaking in Chile. Dietschi was one of the speakers of that conference. We had several meals with with Didier, and in the book he wrote a very nice thing. He did he wrote to David a great mentor. Thank you, Didier. Appreciate that. You're been a great mentor to me, a passionate teacher. Yeah I’m saying that passion kind of like it that drives me. But then he says, and most importantly, a great human being and friend. Theda Santiago, July 23rd, 2023. We treasure those connections and our mentors may not always agree with everything that the student comes up with, but I specifically went to the hands on course with two questions, and these are the questions that I had because I'd already formulated the answers in my head. Why do we always have failure in the floor of the jewel box? That is the place where 90% of failures on adhesive and mechanically retained restorations happen? These deep boxes are the problem. My solution had been there's a different structure that you are bonding to in those areas. Sure, you can call it dentin or root dentin, but what's the difference between root dentin and this dentin up by the cej or in the middle mid coronal that we call intermediate dentin? And of course enamel is obvious, you know, not any moisture or not any collagen and is a very different situation. We have this transition in the interface that we call the DEC Dentino enamel complex, now called the Soft Zone in 1998 by Wang and Weiner. But these ideas of the actual anatomic differences, you have to read some pretty technical stuff to get to those answers. Whoever is listening to this, who is infected by the disease literature mania, I think. Dafina Doberdoli She has that for sure. We have many who have been inspired to go on to the literature, but this book, which is called Oral Structural Biology, is probably the most detailed book ever written, written by a Swiss scientist. Histologist But he understood exactly the miraculous formation of teeth and how intricate they are. They're not just two substances enamel and dentin, but each of those areas have a gradient of what we call the modulus of elasticity, and that's based on the different percentages of collagen versus hydroxy appetite or organic material versus inorganic material. And all of this is hydrated by 20% water. So an average analysis would be hydroxy appetite, 50% inorganic collagen and 30% organic and water 20%. But as we go from the DEC all the way down the root, there's a gradient less water, more water college of the top, but more college in as you go into the root percentagewise and the hydroxy appetite is just the reverse. We have less and less hydroxy appetite. The closer we get to the pulp, which we call deep den or circum pulpal dentin or in the root, more collagen and more water. The deeper you go, more flexibility, more what we call toughness versus brittleness. It's bad if you had to wear and had a chew against that material, but it's great if that stress reduces the occlusal forces that are coming through mastication millions of times a year. And that's exactly the design the teeth have, and that's why teeth from last for 100 years. Hubert Schroeder changed my life. And that book came from a very inspire aspiring early mentor named Tim Rainey. And I believe that that's where we'll go with our next lecture. So until next time, get bonded. Stay bonded. Always great to talk to you about biomimetic dentistry.