Very Dental: Dr. John Burgess was One of the Great Ones!

[00:00:01] This is a production of The Very Dental Podcast Network.

[00:00:05] This is The Very Dental Podcast

[00:00:17] Welcome to The Very Dental Podcast where you'll find entertaining and relevant conversations with visionaries, clinicians, and your friends in the dental space.

[00:00:26] Now here's your host Dr. Alan Mead. Very Dental people welcome back to another episode of The Very Dental Podcast.

[00:00:33] I still am here in Arizona. I'm kind of sitting outside the exhibitor like area for the Spear Summit 2022.

[00:00:40] And they have a speaker going right now, so it's a little quiet out here and I have the chance to speak with Dr.

[00:00:46] John Burgess today. John, how are you doing? I'm doing well. Thank you. So something you don't know about me.

[00:00:52] I'm from Michigan and I saw you speak at the Vetter Society.

[00:00:57] I don't know if you remember that. It was several years ago and you did a one-day program and it was in Lansing.

[00:01:03] It's really funny. You did a lecture here at the Spear Summit yesterday. It was very, very

[00:01:11] kind of in-depth on kind of what we know about adhesives and stuff like that.

[00:01:14] I'm gonna talk to you about that a little later too, but there's a lot of...

[00:01:20] I have a little John Burgess sitting on my shoulder a lot of times when I'm working because I heard some of the stuff you said

[00:01:26] at the Vetter meeting and then what's cool about when you're lecturing about

[00:01:31] materials and adhesives and stuff like that. Some of the stuff you see at the Spear Summit is pretty

[00:01:39] cutting-edge. You know what Greg Kinzer gets to do in his office is maybe not what I get to do in my office all the

[00:01:44] time, but you know what I do do all the time is I use adhesives all the time.

[00:01:47] And we have to choose materials on the regular basis whether we're gonna do zirconia or gold or what in any case.

[00:01:55] So and that's... you do a lot of that because you do a lot of research. Research is kind of your thing and

[00:02:01] more than that, I could go so many places with this, but the little John Burgess on my shoulder is that you said it yesterday too.

[00:02:09] When you

[00:02:10] are applying an adhesive and of course you're supposed to dry it, it's not that you're drying it.

[00:02:16] It's that you're evaporating the solvent and you actually have to know what the solvent is because they're gonna evaporate differently,

[00:02:21] alcohol and that. So I mean, I don't think I had heard that before you said that before.

[00:02:26] And you said you start from a distance with your air syringe and you come in closer

[00:02:30] and I'm just like that makes a ton of sense, but no one, you know...

[00:02:35] Yeah.

[00:02:35] So I've got a little John Burgess sitting there because I have to, you know,

[00:02:39] it'd be easier for me to just go in with my air syringe and just...

[00:02:42] you know, and but I know that that's not what I'm doing.

[00:02:45] Like I actually know, like you help me understand. The other thing that this is really funny

[00:02:49] when you think I use a gel etchant. I've been using the same, it's an ultra dent gel etchant.

[00:02:54] I've been using it a hundred years and you said you need to

[00:02:57] stir it up when you're placing it because this stuff will come out in bubbles.

[00:03:00] And so you could actually have

[00:03:01] a piece of the surface that didn't get etched because it was a bubble.

[00:03:04] So you have to move it around a little bit and

[00:03:06] you have to rinse it for a lot longer than you would,

[00:03:09] your gut would tell you because you really have to neutralize that stuff. And I'm like thinking to myself,

[00:03:13] so every day I've got John sitting on my shoulder.

[00:03:15] And you didn't even know you were sitting on my shoulder. That's the thing that makes me laugh.

[00:03:18] So I wanted to start the interview saying, I heard you.

[00:03:21] And if you get a chance to see John, you really need to because

[00:03:24] he probably doesn't have as flashy of visuals as some of the people that are

[00:03:30] presenting at the summit because these guys are photographers.

[00:03:32] But like there was everyone taking pictures of your slides because you list the stuff that dentists need to see.

[00:03:38] So I welcome you to The Very Dental Podcast knowing that I think very highly of what you do.

[00:03:44] But

[00:03:45] so I'm curious about, I don't know you very well.

[00:03:49] So I'm curious, how did you get into the business of doing what you do?

[00:03:55] And I'm gonna have you describe kind of what you do because you're at LSU now and you run a lot of research.

[00:04:00] But I'm curious, how did you get into the research aspect of dentistry?

[00:04:03] Well, it took me a little while to get into research. I was in the Air Force at the time.

[00:04:10] Trying to find out exactly what I wanted to do.

[00:04:13] I thought I wanted to be one of the generals in the Air Force and stay there forever and all that.

[00:04:20] But the more I started doing biomaterials kind of

[00:04:26] evaluations and testing and the better I liked it.

[00:04:30] And I really got to the point where I remember one day I came home to my wife and

[00:04:36] she was sitting there and I said, you know, I cannot believe somebody pays me to do this.

[00:04:41] Yeah.

[00:04:42] And she looked at me and said, I'm glad they do.

[00:04:44] Awfully glad they do, exactly.

[00:04:45] Well, something interesting too, Air Force, I think the Air Force in particular has,

[00:04:50] like there's a lot of the research we get.

[00:04:53] Why is the military, like why do they have the military or why do they have the research base?

[00:04:58] What about the military is that?

[00:05:01] Yeah, they used to a long time ago when the American Dental Association was just forming

[00:05:07] and they're forming their standards, they needed a standard for amalgam because amalgam was made in

[00:05:14] all kinds of ways.

[00:05:15] Yeah.

[00:05:15] And there was no definite formulation for it.

[00:05:19] And so they turned to the military in part and said, hey, we know your amalgams are failing

[00:05:27] because you're putting all this stuff into these recruits and it's not working and they're on the

[00:05:32] battle line and they're having dental problems.

[00:05:35] And so let's standardize what we're doing.

[00:05:38] And so then they developed the Paffenberg Research Center and we developed all kinds of standards.

[00:05:48] And I've done some work there and I started working over at Wilford Hall, which is our big area,

[00:05:57] the Air Force's big facility.

[00:05:58] It's been downgraded now, but it's a thousand bed hospital and I was working there and so I had

[00:06:05] access to toys, all kinds of toys.

[00:06:07] And so the more I did, the more I liked it and the more inquisitive I got.

[00:06:13] So we started beginning testing and I could look at an article and go, this is terrible.

[00:06:18] And one of the commanders there turned to me and said, if you think that's terrible,

[00:06:22] why don't you do something that you think is correct?

[00:06:24] Interesting.

[00:06:25] And so he encouraged me to do this.

[00:06:27] And so I started and then I moved to clinical research.

[00:06:32] We had a speaker come in and he was talking about, John Osborne was his name.

[00:06:36] And we were talking about different types of clinical research.

[00:06:41] And I thought that is really fun.

[00:06:43] And then Miles Markley, they brought Miles Markley down and he was,

[00:06:50] I was asked to sit in the front for some reason.

[00:06:52] So I sat in the front.

[00:06:53] Okay.

[00:06:54] And I'm sitting here and he goes, this amalgam was a failure.

[00:06:58] And he showed a slide up there with an amalgam.

[00:07:00] And I looked at it and I thought, yeah, I think that thing will probably last a few more years.

[00:07:04] And he said, after 37 years, I had to replace this amalgam.

[00:07:09] And I'm going, I'm not even 37 years old.

[00:07:12] Exactly.

[00:07:13] That's something that's so funny.

[00:07:15] Oh, it was amazing.

[00:07:16] And so that encouraged me further to begin to look at this stuff in the clinical environment.

[00:07:22] And the testing that we do, we try to make it as close to the clinical environment as we possibly

[00:07:27] can because it has more relevance.

[00:07:31] So it turned out well for me.

[00:07:33] Yeah.

[00:07:34] What's interesting about, I think sometimes the military is awfully proud.

[00:07:38] I interviewed a friend of mine, Mike Manziel, who was, he was like a SEREC trainer in,

[00:07:45] I can't remember what, he's a military guy.

[00:07:47] And what was really cool, he's like, one of the great things about having a chance to do

[00:07:50] this stuff in the military is that you kind of have the command and control aspect of it.

[00:07:55] You sort of, and you get a ton of data because you got a bunch of people that you can follow.

[00:07:59] You don't have to worry about following them because they're there.

[00:08:02] You know, so it is interesting.

[00:08:03] It makes a lot of sense that it kind of started with the military.

[00:08:06] But so, and now you have what you're doing at the moment is at LSU and you're doing a

[00:08:13] lot of clinical research there.

[00:08:15] Is that right?

[00:08:15] Yeah, right.

[00:08:16] I run the clinical research area after, and I was there before.

[00:08:20] This is my second time back.

[00:08:21] So first time Katrina came in and wiped out everything that we had.

[00:08:27] We had a good clinical research area going.

[00:08:31] We had, boy, we had amazing people.

[00:08:34] People used to come in and say, you've got the best staff physically for the faculty

[00:08:39] of any place that we've been.

[00:08:41] And so it was good.

[00:08:42] And I really enjoyed that.

[00:08:45] And so I went back to LSU.

[00:08:48] They gave me a nice offer.

[00:08:51] And so I went back.

[00:08:52] I worked two weeks out of the month there.

[00:08:55] And then I go home to Birmingham.

[00:08:57] My wife is in Birmingham, so I go back to Birmingham.

[00:08:59] So it's been a very good environment for me.

[00:09:05] And the transition has been minimal.

[00:09:10] I knew a lot of the people that were there.

[00:09:11] Sure, sure.

[00:09:12] It's like a homecoming.

[00:09:13] Yeah, exactly.

[00:09:13] And it was.

[00:09:14] People would come out from their offices when I walked down the hall and give me a hug.

[00:09:17] And I mean, that's a lot.

[00:09:19] That's fantastic.

[00:09:20] It was very, very good.

[00:09:21] And we're building a good clinical research facility.

[00:09:25] We've got some really good operators replacing restorations.

[00:09:30] We've done evaluations, calibrations, standardization.

[00:09:35] We're on our way.

[00:09:36] That's exciting.

[00:09:38] OK, so one of the classic lectures at bigger dental meetings is sort of, you know,

[00:09:45] a lot of times it's much like what you did yesterday.

[00:09:48] What I thought was funny is you basically said, I don't care what you use,

[00:09:52] but this is what's happening.

[00:09:53] In other words, and I mean, you were not a salesman.

[00:09:57] And I think that's interesting because, OK, I've thought about this a lot,

[00:10:01] but I'm just going to put it out there.

[00:10:03] Going on the exhibit floor in the Chicago Midwinter,

[00:10:07] you can find the very best bonding agents at about 30 different booths because they all say

[00:10:14] that ours is the very best.

[00:10:15] And the story is dentists find sales pitches much more compelling, I think, than research.

[00:10:23] And I do think it's because I mean, I graduated in 1997 and it wasn't great then.

[00:10:29] It can't be much better now.

[00:10:30] They never taught us how to read a paper.

[00:10:32] They never really taught us how to evaluate data.

[00:10:36] They didn't.

[00:10:37] And I mean, on some level, we're busy being clinicians and so, but they don't even,

[00:10:44] I never knew enough to even know.

[00:10:46] So, you know, I think that made me very susceptible to the sales pitch.

[00:10:50] I mean, like that's a fat pitch for John because you're literally, you do clinical research.

[00:10:54] How do you, what do you have to say to that?

[00:10:56] Tell me what you think of that.

[00:10:57] I think that slowly, at least where I am and where I have been, that's changing.

[00:11:03] Okay.

[00:11:03] And what we do is have literature reviews.

[00:11:06] We bring in good papers.

[00:11:08] We bring in terrible papers where they've made all kinds of mistakes and we pick them out and

[00:11:12] we let them pick them out at a period of time.

[00:11:15] And so we work with the prosthodontic group mostly.

[00:11:19] Okay.

[00:11:19] And I also lecture to the dental students themselves.

[00:11:25] So, and.

[00:11:28] Are you able to, in undergrad dental school, are you able to do literature review with them?

[00:11:31] Because that would be, they would pick it up and do it.

[00:11:33] Yeah.

[00:11:34] Okay.

[00:11:34] And that's a fledgling at LSU.

[00:11:39] They had it and then they got away from it, but we're bringing it back again.

[00:11:44] Also, I work with, you know, 10 dental students and we do research projects with them.

[00:11:53] So they learn what a hypothesis is.

[00:11:55] Yeah.

[00:11:55] They learn what the statistics are.

[00:11:57] They learn what the conclusions are.

[00:11:59] They learn how to set it up and design it and I learn how to do it.

[00:12:02] And then they turn around and learn how to publish it as well as look up the literature.

[00:12:07] That is a skill set that even if you're not doing research, I feel like,

[00:12:13] like, you know, right next to, you know, an hour of biochem every day for the first two years of

[00:12:19] dental school, like, just a little bit on scientific, like experimental design.

[00:12:23] I am going to tell you that right now.

[00:12:24] One of the things that there's a couple people that I really look up to,

[00:12:27] one of them is a guy by the name of John Cottamey, who's an endodontist and he's just excellent.

[00:12:34] But more than that, he sort of gave me an in on scientific skepticism.

[00:12:40] And the reality is, is like much of the research you see isn't measuring what they tell you it's

[00:12:45] measuring.

[00:12:45] You know, like, it's like if you look at the experimental design, you realize it's not really,

[00:12:49] saying what they're saying it's saying.

[00:12:51] But the problem is you really have to dig in on some of that stuff and you have to,

[00:12:55] you have to understand the basics of experimental design.

[00:12:57] So he didn't have anything like that.

[00:12:59] And you're a clinician trying to help people with their teeth.

[00:13:02] It's really, it's hard to make that connection.

[00:13:05] It is.

[00:13:06] Like experimental design is fascinating to me because I think people are really good

[00:13:10] at making things complicated when in reality,

[00:13:12] experimental design should be as simple as possible.

[00:13:14] So you can measure what you want to measure, you know?

[00:13:17] This compared to this, compared to this, compared to nothing,

[00:13:19] compared to the best thing in the world.

[00:13:21] Yeah.

[00:13:22] Those are how basically most things are set up.

[00:13:25] So we look at a lot of techniques as well because we run,

[00:13:29] because I run the clinical research area.

[00:13:31] We can take things in the, in vitro or the laboratory environment

[00:13:36] and move it over to the clinic and really see how it works.

[00:13:41] For example, bevels on posterior composite preparations.

[00:13:47] Do you put bevels on them?

[00:13:49] And for a while people were doing it and we,

[00:13:53] I get frustrated because I would talk to different people and they said,

[00:13:57] no, you put bevels on.

[00:13:58] And I go, no, I don't think so.

[00:14:01] And so then we designed a clinical study where half the tooth,

[00:14:07] we put a bevel on.

[00:14:08] Oh, interesting.

[00:14:09] The other half, no bevel.

[00:14:11] And a coin flip determined that.

[00:14:13] So all the working cusps didn't get a bevel and all the non-working cusps did get a bevel.

[00:14:19] So, and at the end of the day, whenever you put a bevel on,

[00:14:23] there was more wear on that restoration and the margins broke down faster.

[00:14:27] Well, you know what's interesting about that too is like you could even,

[00:14:29] that's not even intrapatient variability.

[00:14:33] That's tooth, that's within the tooth you're getting variability.

[00:14:36] That's pretty interesting because you're like, I mean, that's,

[00:14:39] and that's an experimental design thing.

[00:14:41] It's a perfect example of what I'm talking about.

[00:14:42] Like, like you're, you're actually able to measure it in a, in a,

[00:14:46] you're reducing all the variables.

[00:14:48] It's the same damn tooth.

[00:14:49] I think that's really, I think that's really cool.

[00:14:51] I think that's really good.

[00:14:52] But I guess it's, it's frustrating as a, as a clinician because it's, for one thing,

[00:14:58] this probably, this probably curls your hair when people say that,

[00:15:00] well, in my hands, it works fine.

[00:15:02] And I mean, like if you have good hands, you can probably make almost anything work.

[00:15:07] But the problem is you can't design a product for someone with good hands.

[00:15:10] You got to design a product for the, for the bulk of us that are, that are okay.

[00:15:13] You know, like on some level, that's a tough, it's a tough sell, right?

[00:15:16] Yeah.

[00:15:17] The best material is material which is abuse tolerant.

[00:15:21] That's why amalgam is so amazing because you could put it in underwater saliva,

[00:15:26] blood and everything, and it would last 25 years.

[00:15:29] And composites won't do that.

[00:15:31] No, no.

[00:15:32] So they are much more intolerant.

[00:15:34] Yeah.

[00:15:35] And what we are trying to do is build everything into the composite that we can build.

[00:15:41] Yeah.

[00:15:42] So to reduce the number of application, the best adhesive, for example, would be no adhesive.

[00:15:48] It would be an adhesive that's built into the restorative material.

[00:15:51] So you can just put it directly into the tooth, had it maybe like cure it.

[00:15:56] And so there's going to be changes.

[00:15:59] Yeah.

[00:15:59] Changes are coming.

[00:16:01] Yeah.

[00:16:01] That's interesting.

[00:16:02] That's interesting.

[00:16:02] And you'll probably get a chance to, what's interesting now, you get a chance to see all

[00:16:06] the materials they put in for it.

[00:16:07] You're actually putting with people's mouths.

[00:16:08] I mean, that's kind of great.

[00:16:09] It's really fun.

[00:16:10] So when you're doing clinical research, how, and you're at the, I'm assuming you're right

[00:16:15] in with the dental school.

[00:16:16] Is that right?

[00:16:17] Okay.

[00:16:17] So how do you screen patients for, you know, because on some level it's like,

[00:16:25] I have a couple of questions that go along with this, but it's like, you got, you got,

[00:16:28] I mean, dental schools are a great place to do this because you've got a lot of people

[00:16:30] coming through and you can, you can do a lot of things for people, but it's hard to

[00:16:33] standardize stuff.

[00:16:35] It's really hard to standardize what, you know, what one person needs over another.

[00:16:38] And you're actually trying to measure different materials and different.

[00:16:40] So how does, how do, how does a patient get into the clinical research facility?

[00:16:45] Yeah, we advertise and we advertise sometimes in the newspaper, sometimes on television.

[00:16:51] Sometimes we put flyers up all over the place and they call us.

[00:16:56] We have a person sitting at the research desk.

[00:17:00] So she takes the call and, and talks to them.

[00:17:03] We have a script that's written out.

[00:17:05] So it basically describes the study that we're looking for.

[00:17:09] Okay.

[00:17:09] Non-carious cervical lesions.

[00:17:11] Yeah.

[00:17:12] I'm going to talk to you about that in a second too.

[00:17:13] Carious lesions, whatever they are, that person will describe it because they'll read it.

[00:17:19] And so they.

[00:17:20] So the patients when they're being screened, get the same message every time, which actually is,

[00:17:24] you're also reducing the variability there.

[00:17:26] And then we have a lot of forms.

[00:17:28] I've never seen so many forms in my entire life.

[00:17:30] Yeah, that makes sense though.

[00:17:31] Yeah.

[00:17:32] Yeah.

[00:17:32] That's a packet.

[00:17:33] Yeah.

[00:17:33] And we go through the consent form, tell them exactly what it is.

[00:17:38] In this particular study that we're starting now with 3M, they supply the composites.

[00:17:47] We use one composite.

[00:17:48] We use two adhesives, an older adhesive, Scotch bond multipurpose and a newer adhesive, which is

[00:17:56] Scotch bond universal plus.

[00:18:00] Yep.

[00:18:00] Yep.

[00:18:00] Yep.

[00:18:01] And so it's relatively new on the market, but they want clinical proof that this stuff works

[00:18:06] better than the other before they make that transition to the new one.

[00:18:11] So they're both on the market.

[00:18:13] You go downtown and have a private dentist put the same restoration in,

[00:18:17] except you'd have to pay for it.

[00:18:18] We don't charge them anything.

[00:18:20] The sponsors pay for what we're doing.

[00:18:23] Okay.

[00:18:23] So they pay the incentive.

[00:18:26] I give people cleanings every time they come in and all that sort of stuff just to keep them

[00:18:30] coming back in.

[00:18:31] Yeah.

[00:18:32] And our retention rates are generally pretty good, but we try to make sure we have inclusion

[00:18:39] criteria and exclusion criteria built into the protocol.

[00:18:43] The inclusion criteria is you have to have so many teeth.

[00:18:47] You have to have a carious lesion.

[00:18:49] You have to be able to come in.

[00:18:51] You have to have good oral hygiene on and on and on.

[00:18:55] The exclusion criteria would be, well, the only thing you have are curious teeth and we're not

[00:19:01] looking for those.

[00:19:01] We're looking for non-carious cervical erosions or raisins.

[00:19:06] And so we look at those and I do the screening.

[00:19:10] So patient comes in, I look at this, we measure the depth of these lesions.

[00:19:15] And for non-carious cervical lesions, they have to be 1.5 millimeters deep or deeper.

[00:19:20] And we use a perioprobe to do that.

[00:19:22] And we've tried different ways to do it and impression and measuring it would be the best

[00:19:27] way, but that's another.

[00:19:30] Yeah.

[00:19:32] That's a whole other level of precision, I guess, which makes sense.

[00:19:40] And for a while, we were actually making impressions and scanning the depth of those

[00:19:45] lesions on a scanner so that it was very accurate.

[00:19:49] And we did that.

[00:19:50] And what we found was that the higher the occlusal forces on that tooth, the faster

[00:19:57] those non-carious cervical lesions would progress.

[00:20:01] Doesn't mean that that's the only ideology because we looked at diet, we looked at

[00:20:06] toothbrushing techniques and they carried around a diet and wrote down all the food

[00:20:11] that they did and all that.

[00:20:13] And we then discovered occlusal forces were the main factor, but you had a lot of other

[00:20:21] factors contributing to the non-carious cervical lesion.

[00:20:24] It's really funny that there's, that's an argument that gets pretty heated in dentistry.

[00:20:30] I know.

[00:20:30] I remember you were talking about it then and it's not gotten any less heated since

[00:20:34] I heard you talk about it.

[00:20:35] That's exactly right.

[00:20:36] So there's people that believe a lot of stuff there.

[00:20:38] And what's really interesting is I thought about it when you were talking yesterday.

[00:20:41] The non-carious cervical lesion is sort of, for a bonding agent, that's a tough challenge.

[00:20:47] That's probably the, and it's one of the, I guess it makes the most sense to measure

[00:20:51] it on that.

[00:20:52] When I'm seeing, you were showing some data showing retention of those things in the

[00:20:57] really high percentage.

[00:20:58] And I'm like, man, that's a hard restoration to restore.

[00:21:02] It's got no natural retention whatsoever.

[00:21:04] You're completely basing it on the, and so, and I was thinking like, that's why the non-carious

[00:21:08] cervical lesion is the standard because I mean, literally you're, the only thing holding

[00:21:12] it in there is the bonding agent.

[00:21:14] So, so they got to have their stuff figured out there.

[00:21:17] It's interesting too.

[00:21:19] And you're right.

[00:21:19] That is a very difficult standard.

[00:21:23] The surface of the non-carious cervical lesion is atubular.

[00:21:27] And so if you look at it, it's sclerotic dentin, it's very hard and there are no tubules there,

[00:21:32] one or two, I mean, not many.

[00:21:34] And depending upon the sclerosis, but it's like a scar.

[00:21:37] And so you've got to break through that scar somehow.

[00:21:40] A lot of people make undercuts, a lot of people grind on the whole thing.

[00:21:45] We etch and that works out very well.

[00:21:48] But if John Gwinnett has shown that when you go through that scar, right through the sclerotic

[00:21:57] dentin, you increase the bond by 40%.

[00:22:01] Well, if you lose that tubular penetration, that's 40% of the bond.

[00:22:06] So, so you've got to make sure that you're going through it.

[00:22:10] That's one reason why the retention rates have gone up so much.

[00:22:13] Plus we've got materials now that bond to the calcium.

[00:22:17] And so the bonds, they're giving you a chemical bond, which is different than the hybrid layer

[00:22:22] inclusion over the collagen.

[00:22:24] So that's a micro physical bond on that.

[00:22:26] I get it.

[00:22:27] That's interesting.

[00:22:27] Some of you put yesterday, I thought was really funny.

[00:22:30] You literally were showing just the ingredients in all the new bonding agents.

[00:22:34] The list of ingredients, like they're throwing everything, you know, they're throwing everything

[00:22:38] at the wall to see what works.

[00:22:39] And I'd like you to say a little something about that because like, well, we'll put some

[00:22:44] of this in, we'll put some of this in it, which is really interesting.

[00:22:47] It's one of the reasons to maybe look at some of the newer things because they're, they're

[00:22:50] sort of doing a lot.

[00:22:51] I think that's what the universals would be right?

[00:22:53] Like they say something about that.

[00:22:57] Well, it started off the first universal that was being developed.

[00:23:02] I went to a big laboratory of one of the companies and they wanted me to test it.

[00:23:09] And so in the laboratory, so I said, okay, yeah, I do a lot of that.

[00:23:14] It's not a problem.

[00:23:15] So I talked to them about what they had in it.

[00:23:18] And I thought, man, that stuff's going to be hard to keep in the same solution without

[00:23:24] layering, having rich areas and poor areas.

[00:23:27] And well, and then they dumped in the HEMA and stuff.

[00:23:31] And all of a sudden things started becoming one layer, one big layer.

[00:23:35] And you didn't have to shake the vial and all that.

[00:23:39] So it really takes a lot of work to balance these things out.

[00:23:45] And that's why initially I thought, okay, if you took the top off and left the top off

[00:23:50] and the solvent evaporated out of that, it's going to change the dynamics of that entire

[00:23:55] system.

[00:23:56] Yeah.

[00:23:57] But it doesn't.

[00:23:58] Interesting.

[00:23:59] Interesting.

[00:23:59] They really, I mean, the chemists at these big companies are amazing.

[00:24:05] Yeah.

[00:24:05] They really are.

[00:24:06] They're very intelligent people and they work hard.

[00:24:10] Okay.

[00:24:10] So I got another, this is something I wanted to ask you for years because I think that,

[00:24:15] so here's the thing.

[00:24:16] Dentists are not awesome at necessarily reading directions, I think.

[00:24:21] Because, okay, so let's just say you've been using a certain bonding agent or etching a

[00:24:26] certain way for a really long time and it seems to have worked for you.

[00:24:29] And so there's a new material and you're like, well, of course it works like the old material.

[00:24:32] I think we're probably notorious for that.

[00:24:35] But also I want you to comment, how often should you go back and read your instructions?

[00:24:40] And they do change.

[00:24:41] They do.

[00:24:43] But also dentists, this dentist, me, I apparently I put my own spin on things when I,

[00:24:50] because I have gone back and read the instructions of a material I've been using for a long time.

[00:24:55] I'm like, wow, that's not what I'm doing.

[00:24:58] And maybe they have changed.

[00:24:59] But the reality is like, honestly, listeners do this and then report back to me.

[00:25:05] You might not be using it the way that the manufacturers are recommending because

[00:25:09] you sort of don't remember it.

[00:25:10] So tell me about that.

[00:25:13] A person told me a long time ago, dentists don't read.

[00:25:17] That's true.

[00:25:18] And it's unfortunately, every material comes with the pictures.

[00:25:22] Thank God.

[00:25:22] Right.

[00:25:23] The pictures help.

[00:25:24] Yeah, really.

[00:25:25] And the Mac showed that really quite well.

[00:25:28] But a lot of times what we do is test each specific direction to see what kind of an

[00:25:37] effect it has on the adhesion of that adhesive or that composite or ceramic.

[00:25:45] We do a ton of ceramic testing.

[00:25:50] I know zirconia well.

[00:25:52] I know you do.

[00:25:53] Yeah.

[00:25:54] And so we really have worked hard on that, but we test the manufacturer's directions.

[00:26:00] Is this firing time okay?

[00:26:02] What happens to the translucency?

[00:26:04] What happens to the strength?

[00:26:06] What happens to the crystals that are in the zirconia if you over or under fire it?

[00:26:12] Does it affect translucency?

[00:26:14] It certainly does.

[00:26:15] So you can use the right material, but abuse it on the other side and get terrible results

[00:26:21] when in reality, the material is a good material.

[00:26:24] So I try to emphasize that and we try to do research on the different steps that manufacturers

[00:26:30] are espousing.

[00:26:33] The assumption has to be that the manufacturers really do want you to do it this way.

[00:26:38] They're not taking their instructions lightly.

[00:26:41] They've done a lot of research on the front end of this stuff so that you do it the way

[00:26:44] that they're describing.

[00:26:45] And I'm sure they work in tolerant, make it as tolerant as possible, but there's a reason

[00:26:50] that the instructions are the way that they are.

[00:26:52] It's amazing how much time, effort and energy they really put into the directions.

[00:26:59] And I've gone, well, what's the deal?

[00:27:01] Just change the directions.

[00:27:03] They go, uh-uh.

[00:27:04] It's got to go all the way back through the FDA again.

[00:27:06] Oh boy.

[00:27:07] I go, you're kidding me.

[00:27:09] All the way back.

[00:27:10] Okay, so the regulation of it makes it that much harder too.

[00:27:12] It's tough because as a dentist, you're busy filling an MO on 15 and you're not thinking

[00:27:18] about there's a lot that went into this product to be used a certain way.

[00:27:22] And so, okay, this is just a message.

[00:27:25] We're going to like next time at the office, go read your instructions and see how you

[00:27:28] do it because I'm going to do it when I get home too.

[00:27:30] We have calibrations for the clinical research area.

[00:27:33] We'll sit down, we discuss it, the inclusion, the exclusion criteria.

[00:27:38] And if they see something that's wrong along the way, we exclude that patient.

[00:27:43] They also have calibrations on how to apply it, insert it incrementally, bulk.

[00:27:50] And then also we put in how to finish it because we want the finishing to be very standard.

[00:27:57] The nice thing about doing clinical research with multiple companies is that I get to

[00:28:03] use multiple companies stuff.

[00:28:07] 3M will come in and they want it done this way with their instrumentation, the polishing

[00:28:13] stuff.

[00:28:13] Cogden Supply will come in and they want it this way.

[00:28:15] Ivoclar will come in and they want it this way, which is, at first I thought, oh man,

[00:28:19] why do I have to use this?

[00:28:21] But then it turned out to be a real blessing there because I got to use each one of these

[00:28:28] materials and it got an expertise on them.

[00:28:31] And so I knew then which one was working better because I'd used them personally and looked

[00:28:36] at them and they did work.

[00:28:40] So I'm going to shift gear a little bit because this is also something I heard at the Venner

[00:28:45] Society that really surprised me because, it didn't surprise me, but I take to heart

[00:28:51] what you said.

[00:28:53] Zirconia of course is as a crown and bridge indirect on a tooth, which obviously we talk

[00:28:59] about full arch Zirconia.

[00:29:02] I'm talking about as a crown has become, I don't know if it's the most popular, but it's

[00:29:07] got to be close to the most popular, most used at this point.

[00:29:10] And that, I think that seems like a pretty quick adaptation and there's a lot of reasons

[00:29:13] for it because you just don't see the breakage and it looks nice enough, particularly in

[00:29:17] the posterior that, I mean, I'm going to tell you, I use it a ton myself.

[00:29:21] I don't think that when this was sold to dentistry that they explained how important it is to

[00:29:28] have a well polished surface to us.

[00:29:31] Like the wear, you explain this, the wear properties of Zirconia are terrific, but only

[00:29:38] if it's very well polished.

[00:29:40] And I think, I mean, over the last year, I've kind of realized that I think dentists sometimes

[00:29:45] think about polishing as sort of like that last step.

[00:29:48] We're almost on the home stretch.

[00:29:50] You know, I just got to drop some floss in there and polish and they're out of here.

[00:29:53] And I'm thinking to myself, you know, you might be able to get away with that on some

[00:29:56] materials, but particularly for Zirconia, I think that we sort of missed that a little

[00:30:01] bit.

[00:30:01] Can you say something about that?

[00:30:02] Sure.

[00:30:04] We really did a lot with Zirconia when it first came out and we were working a lot with

[00:30:09] 3M and then Ivoclar and then Karari began to work a lot with us.

[00:30:15] And so right now the Katana, which is Karari, the biggest selling material on the market,

[00:30:22] their Zirconia is very good.

[00:30:23] It's layered and they have little blocks in the pucks as well.

[00:30:27] And the blocks are colored and they actually diffuse those colors so that there's a really

[00:30:34] good transition from the bottom, from the general.

[00:30:36] Pretty neat.

[00:30:37] Yeah.

[00:30:37] It's really a nice material.

[00:30:40] And we measured wear.

[00:30:42] We've got big wear machines at UAB and we were measuring.

[00:30:46] You had slides of those.

[00:30:47] It's those machines are something else too, by the way.

[00:30:50] Yeah.

[00:30:51] I designed the first one on a napkin and took it down to, we've got a prototyping shop

[00:30:56] downstairs that would build all this stuff.

[00:30:59] And so I took it down.

[00:31:00] The guy looked at it and laughed at me.

[00:31:03] I said, no, I really want to.

[00:31:04] No, seriously.

[00:31:06] And so he said, well, we'll make a drawing of this to scale and I'll bring it up to you.

[00:31:12] I go, oh, okay.

[00:31:13] And he said, do you want to do this?

[00:31:14] Do you want to do this with this?

[00:31:15] Do you want to be able to exchange and ask all kinds of questions?

[00:31:18] And that's what a prototyping shop is.

[00:31:20] A machine shop.

[00:31:21] Okay, you've got to have this.

[00:31:22] You've got to have this hole and how big is this hole and all that sort of stuff.

[00:31:26] But the prototyping shops interested in improving the machines that you're using.

[00:31:30] So it's been a wonderful relationship with those guys.

[00:31:36] And I spent a lot of time down there, but we found out with zirconia, the wear really changed.

[00:31:44] I thought initially that if you had just all zirconia surface, because it's three times

[00:31:49] harder than enamel, I thought, I thought, well, that zirconia is going to eat the enamel up.

[00:31:53] This is crazy.

[00:31:55] And so I said, okay, let's measure this.

[00:31:58] And so we started off measuring with an overglaze.

[00:32:03] Well, the overglaze ate the opposing enamel up until you broke through that overglaze.

[00:32:09] And so, okay, well, let's see.

[00:32:12] Let's try other ceramics.

[00:32:13] And then let's try the zirconia unpolished.

[00:32:19] Well, it was not like felspathic porcelain, like porcelain fused to metal.

[00:32:26] That surface on the porcelain will eat up the opposing enamel.

[00:32:33] Oh, yeah.

[00:32:33] Just eat it up.

[00:32:35] And this was much kinder in the very beginning, even though it was still rough.

[00:32:39] And I went, huh.

[00:32:42] Wasn't what you'd expect for that hard of material.

[00:32:44] Yeah.

[00:32:45] I made him repeat the entire experiment.

[00:32:46] You didn't believe me.

[00:32:47] I didn't believe it.

[00:32:49] And so we repeated it again and I said, well, okay.

[00:32:53] I said, okay, let's polish it.

[00:32:54] And so I did the polishing on all these specimens and learned which ones would do really quite

[00:33:00] well.

[00:33:01] And so we did.

[00:33:02] And we put the polished zirconia surface in and measured it against an enamel cusp.

[00:33:08] It comes down, hits, slides and goes back up.

[00:33:12] So it was like going through an excursive movement all the time.

[00:33:15] And then we would scan that surface and very accurately down to the micron level tell you

[00:33:22] exactly how much wear was occurring.

[00:33:24] And we had a lot of materials that did wear, but the zirconia polished just doesn't wear.

[00:33:34] I mean, it doesn't wear the opposing enamel.

[00:33:36] And then we got into this thing where, well, if it doesn't wear, is it going to be in hyper

[00:33:42] occlusion over time?

[00:33:43] Well, fortunately you have the periodontal ligament that compensates for that.

[00:33:48] But we've had now so many zirconia restorations in the posterior part of the mouth that there's

[00:33:55] no problem where it would have shown up way before.

[00:33:58] It's really interesting.

[00:33:58] The same Vetter Society meeting that you came and spoke at in Lansing, we had it this year

[00:34:03] in Lansing and a guy by the name of Tomas Linkovicius was there.

[00:34:07] And he talks a lot about implants and there was really interesting, the underside of a

[00:34:12] zirconia crown and an implant well polished has magical properties.

[00:34:18] It's interesting how this material has literally, you could hate on it, but all of a sudden

[00:34:23] you're like, man, this is really revolutionizing.

[00:34:25] It's not really expensive.

[00:34:26] And we've really kind of, I mean, in my career, in my span, I've been practicing for 25 years.

[00:34:33] It's a wildly different landscape of what you do to crown a tooth now.

[00:34:38] And you could cement them.

[00:34:40] And I do, I do.

[00:34:42] Okay, so let's just talk about that.

[00:34:44] Everyone loves to get so complicated with their bonding procedures.

[00:34:47] I'm like, why the hell you do that?

[00:34:49] I mean, if you've got reasonable retention and to be honest, most of the crowns I do,

[00:34:53] I would argue even most of the second molars I do, I got decent retention on it.

[00:34:58] Have you ever had to cut one of those off that you just cemented?

[00:35:02] I don't know that I need to bond it, but you say that around people and they're just like,

[00:35:06] oh, I don't even know what you're talking about.

[00:35:08] I mean, I'm going to cement it every chance I get because why not?

[00:35:11] Am I crazy to say that?

[00:35:13] No, if you've got adequate preparation, the walls are reasonable parallel, sorry.

[00:35:21] And you've got three to four millimeters of actual preparation height.

[00:35:27] You're in pretty good shape.

[00:35:28] You can cement those.

[00:35:29] And we started off with the first clinical study on zirconia with 3M here.

[00:35:38] And they told me, I said, how much do you reduce it?

[00:35:43] They said, well, you reduce it two millimeters on the top for the porcelain that's going to go on

[00:35:48] the top and then you reduce it again six tenths of a millimeter for the zirconia or maybe a little

[00:35:54] more.

[00:35:55] Okay.

[00:35:56] Well, that means that you've reduced this thing almost three millimeters.

[00:36:00] There are some teeth that bicuspid is a real short second molars or sometimes really short.

[00:36:07] And you're sitting there looking at this and go, well, that's just about even with a soft tissue.

[00:36:11] Yeah.

[00:36:11] We haven't yet.

[00:36:11] We've run out of room.

[00:36:12] Yeah.

[00:36:13] I'm going, how in the world is this going to work?

[00:36:15] And so I'm bonding these things in for this study and I was looking at this one tooth and it was

[00:36:24] really a short tooth.

[00:36:26] And I thought, man, if this were a casting, I'd put a groove here.

[00:36:30] Yeah, yeah, exactly.

[00:36:31] And it would work fine.

[00:36:32] No problem.

[00:36:33] We didn't have to worry about it.

[00:36:34] So I said, I'm going to try that.

[00:36:36] Yeah.

[00:36:36] And I put grooves in those things, sent them off to the laboratory.

[00:36:40] They milled those things right out and sent them back to me.

[00:36:42] And the crown came back and didn't go like this.

[00:36:45] It went straight down.

[00:36:48] And so it made cementation much easier.

[00:36:51] Gave me that option to put a groove there and be happy about it.

[00:36:55] But zirconia has transformed the way we do dentistry now.

[00:37:00] And there are a number of resin cements that are amazing in that they've worked hard on

[00:37:07] these things to duplicate cement removal.

[00:37:11] And it was mentioned yesterday in one of the lectures that cement removal is a very difficult

[00:37:19] thing.

[00:37:20] Well, yes and no.

[00:37:21] If you're using the right resin cement with a prolonged gelation time, it absolutely is.

[00:37:27] Simplifies it a lot.

[00:37:28] Simplifies it amazing.

[00:37:29] I mean, the Panavia, I got to make sure I get this one right.

[00:37:37] Panavia 21, no, Panavia SA Universal.

[00:37:42] Okay.

[00:37:42] Okay.

[00:37:42] Panavia SA Universal has two syringes.

[00:37:46] One side of the syringe contains a long silane.

[00:37:51] It's a different silane than what you'd use in your bottle.

[00:37:54] It's a silane they use to put on the filler particles so they stay in the composite.

[00:38:00] Up here is the 10 MDP monomer.

[00:38:04] If you mix the two together early, you mess up everything.

[00:38:08] It really is a mess.

[00:38:10] So by golly, going through that little baffle down here at the end, this works really well.

[00:38:15] And they increase the gelation time.

[00:38:18] So do you remember zinc phosphate cement?

[00:38:21] Sure.

[00:38:21] And you could take, we'd wait, wait, wait, and the whole thing would come right off.

[00:38:27] That's the cement.

[00:38:28] That's huge.

[00:38:28] That's yeah.

[00:38:29] And boy, I did that the first time and I went, I'm hooked.

[00:38:32] Yeah.

[00:38:33] Well, I mean, that's the reason that resin cement makes people like me nervous because

[00:38:37] it's the cleanup.

[00:38:38] If you don't get it, man, that's the worst part of your day.

[00:38:41] 12B blade and sit there.

[00:38:43] Oh yeah.

[00:38:44] Oh yeah.

[00:38:44] And it's, and as Jeff said, it's like, yeah, you want to, patients need to be numb for

[00:38:48] this.

[00:38:48] If you got to get in there and do it.

[00:38:49] That's exactly right.

[00:38:50] It's exactly right.

[00:38:50] Okay.

[00:38:51] So I'm going to one more question on zirconia.

[00:38:53] So knowing that so much of zirconia, a lot of people are using digital impression techniques

[00:38:59] or whatever.

[00:39:00] And honestly with milling, a lot of the accuracy is really quite good.

[00:39:04] I'm finding that a lot of times, a lot of times, you know, you're cementing and the bite's kind

[00:39:09] of dead on the money because, you know, we've given them a really accurate scan and we really,

[00:39:14] and so I want my lab to send it back polished because a lot of times I don't have to adjust

[00:39:19] the occlusion at all.

[00:39:20] And why, why have me go through the polishing?

[00:39:23] So like, you know, uh, and I, some labs want to glaze it cause that's what they've always

[00:39:29] done.

[00:39:29] And it's like, you kind of have to have that conversation on some level.

[00:39:32] I wonder when, will it become standard that these things come back polished instead of

[00:39:35] glazed or is it just because it's so easy to glaze it?

[00:39:37] So yeah, I really do.

[00:39:39] Um, the thing is if you've got a posterior tooth by cuspid, for example, you can glaze

[00:39:46] the facial surface, but just leave the occlusal interesting, polish the occlusal.

[00:39:50] That's all you really have to do.

[00:39:51] Yeah.

[00:39:52] And it works out well.

[00:39:52] It simplifies your procedure across the board.

[00:39:54] So yeah, I know there's a lot of dentists that don't want to have a, um, a lab handpiece in

[00:39:59] their office or whatever they want.

[00:40:00] And I'm just like, I know they got to do it.

[00:40:02] It's so much easier, so much easier if you have a lab handpiece with wheels and just like,

[00:40:05] it's a piece of cake.

[00:40:07] I don't know.

[00:40:08] I just, that's in, and I have to remind myself cause yeah, it'd be a lot easier not to have

[00:40:13] to spend a lot of time polishing, but it's such an important part, particularly for that

[00:40:16] material.

[00:40:18] And there's a lot of polishing systems out there, the Messner polishing system, which

[00:40:24] a lot of people recommend, but, uh, a good economical system is the axis bike by Kerr.

[00:40:31] Okay.

[00:40:32] And it polishes, it polishes it until it's like a mirror.

[00:40:38] I mean, it's that part and we measured the reflectivity of the system.

[00:40:41] So that's how we actually knew what the poly, what the, how polished it was.

[00:40:46] Yeah.

[00:40:46] That's, that's really interesting.

[00:40:47] So the last thing I want to tell you, you were, you were sort of laughing about you,

[00:40:51] you had made your, made it very clear about getting an honorarium for speaking here and

[00:40:57] explaining that these are people that you work for and you've taken.

[00:41:00] And I'm curious about your thoughts on, on, on that kind of disclosure and how we should

[00:41:07] probably do better in dentistry than we do, particularly in a continuing education situation

[00:41:11] where, cause, cause what happens is, is someone with credibility, whether it's me saying,

[00:41:17] I like something on a podcast that someone's been listening to a long time, or you being

[00:41:20] John Burgess in front of a group or whatever the influence, we can sell stuff without even

[00:41:25] trying to sell it.

[00:41:26] If we say that we love this stuff and they look, they look to us because everything's

[00:41:30] kind of a shortcut to doing the, to knowing and understanding the real research.

[00:41:34] So on some level, how does, how does a dentist take that ethically?

[00:41:38] Like how, how can someone who's in a position of influence, how, you know, what's the best

[00:41:42] way to handle that?

[00:41:44] That's a tough question, but I'm just curious what you think about it.

[00:41:46] It is, but I take that to heart.

[00:41:48] I really do.

[00:41:49] And I remember the first one of early was lecturing early and I made a comment about

[00:41:55] an adhesive and I said, this adhesive is giving us the best bond strength that we've

[00:42:00] ever recorded.

[00:42:01] And I was walking, I finished the lecture, I was walking down the aisle and the people

[00:42:06] from that company came up and said, thank you for talking about our material because

[00:42:11] we had people all the way out the building lined up to buy our stuff.

[00:42:16] And I'm like, Oh my, that wasn't the intention.

[00:42:18] No, it was not.

[00:42:20] And it scared me.

[00:42:21] It really did because I didn't want to be responsible for something that might show

[00:42:26] up six months from now or a year from now.

[00:42:29] And so that was different.

[00:42:34] I know no manufacturer tries to make a bad product, right?

[00:42:37] None of them do.

[00:42:38] And a lot of people treat manufacturers like that's the way it is.

[00:42:42] But I tried to look at those people as partners because we give them feedback and they modify

[00:42:47] materials because they won't forgive them.

[00:42:49] Sure.

[00:42:50] And so I try, what's the best material?

[00:42:54] Well, okay, this is good.

[00:42:56] This is good.

[00:42:56] And this is good because I know there's three are going to be really good.

[00:43:00] What's the best?

[00:43:01] Of course, everyone wants to, because they want the shortcut, John.

[00:43:03] They want the shortcut.

[00:43:04] They don't want to have to do any thinking.

[00:43:06] But they'll put you in a corner and sometimes you go, well, okay, I use this material because

[00:43:12] I found that it's pretty robust and it's abuse tolerant and it gets the job done.

[00:43:20] But I try to give them more than one.

[00:43:23] You did very well yesterday and you noticed that I haven't asked you about any specific

[00:43:26] materials right now because I don't want to, like partly they need to come see you speak or go to

[00:43:31] the website or, and John graciously gives out his actual email address, which I know that he answers

[00:43:38] and like his cell phone number and stuff like that because he wants to help.

[00:43:41] But the reality is, it's an interesting thing because people are listening and

[00:43:48] they want to know what works.

[00:43:49] They want to know what works, but it's also, it's not like your job to sell them on anything

[00:43:52] in particular.

[00:43:53] It's kind of hard.

[00:43:54] It is.

[00:43:56] It's a balancing.

[00:43:57] It is.

[00:43:58] It is.

[00:43:58] Because you don't, like if a material is really good, you kind of want them to know.

[00:44:01] I mean, you want them to know that it's good stuff.

[00:44:04] It's interesting.

[00:44:05] If there's a major advantage with this material over the other materials,

[00:44:08] and that's kind of how development works.

[00:44:10] Things will be going along very smoothly and then all of a sudden one company will discover

[00:44:15] something, the MDP molecule.

[00:44:16] MDP molecule, your monitor, exactly.

[00:44:18] Yeah.

[00:44:19] And then people need to use that.

[00:44:22] Yeah.

[00:44:24] The patent literally just in the last year or two years came off.

[00:44:27] And so all of a sudden, you look at the ingredient list and it's in everything now.

[00:44:31] Yeah, exactly.

[00:44:32] Which, well, I mean, that actually tells you that they tell you all you need to know on some level.

[00:44:36] It's doing well.

[00:44:37] Yeah, definitely.

[00:44:38] John, this was a real pleasure.

[00:44:39] I really appreciate you having me on.

[00:44:40] And I think you guys will have a lot of questions.

[00:44:44] And guess what?

[00:44:44] I've got John's email address.

[00:44:45] I'll make sure you guys get hooked up with him.

[00:44:47] And I really appreciate that you got to speak here.

[00:44:49] So thanks a ton for being on.

[00:44:50] I appreciate it.

[00:44:50] Thank you.

[00:44:51] I really appreciate your enthusiasm and your inquisitiveness and your trying to help people.

[00:44:55] Yeah, definitely.

[00:44:56] That's the bottom line.

[00:44:57] That's the best thing.

[00:44:58] Yeah. Thanks, John.

[00:44:59] Okay.