21/22: Microbiology of Dental Caries

Transcribed by Sabrina Khan 08/08/2014

The Microbiology of Dental Caries I Lecture #23&24 Diagnosis and Treatment of Oral Disease by Dr. Caufield !*Note: There was a delay in the podcast so the correlation between text and the slides is a little off. !Okay, so good news- what do we have half the class? What do you guys have no fear anymore? Got to up the ante. Good news, we just had the host parasite relationship lecture, thats fresh in your mind. So were going to segue way into this lecture, because its very important. Theres nothing I like talking about more than dental caries, its the subject of my research. It also obliges me to talk about not dental caries, or what will be on tests or what everyone else thinks about dental caries; Im obligated to tell you what is on the new frontiers of what we know about dental caries- its all changed. The high likelihood is that I can confuse you if I go back and forth too much. So Im going to start with the traditional stuff. Some of you will ask me is this going to be on the test or is that on the national boards? Ill try to cover those type of things but most of that is wrong. Or we think is wrong. !So I dont know, its a dilemma because youre paying a lot of moneypart of it goes to research-and in research you make new discoveries, doesnt mean its right. It just means that theres new discoveries and I think we have an obligation to tell you that but Ill try not to confuse you. Were not going to go through DNA sequences today, some people do that to impress and Im more interested in, I hope, educating. !Some of you have come up to me after class and asked some extremely good questions- congratulations, thats the point. Number two, sometimes I get into my standup comedy thing- please forgive me if I offend anyone. Although the topics are serious, sometimes we need some humor, especially on a Friday. I do. So its not to minimize my topics, Im talking about bubonic plague and ebola and Im making a joke, this is not probably what I should do, but sometimes we get a little too serious. Okay, so those are my prefaces and Ive got some interesting slides and some of this information is only months old so lets ..Ill try to make that distinction. !So were talking about dental caries. Dental caries is an infectious disease. Oh boy. So we talked about host parasite relationship, Ill recap some of that. But theres some big problems with our interpretation of what that is and that has to do with some of the traditional microbiology rules and tenants. Since 1960 its been called a transmissible disease. So think about it- infectious, transmissible- those are two words that tend to go together. With those infectious diseases that affect humans, I showed you last time influenza, measles, mumps, HIV, etc. Those types of infectious diseases from the 1960s that was predominated with thinking of any infectious disease, it has to fit some rules. Not the rules I gave you for host parasite, but the rules of ! ! of !1 23


In your microbiology class did thou have Kochs postures? Okay, Ill reviews them briefly and youre going to tell me why Kochs postulates may not apply to dental caries. !Let me develop the theme, please stop me if this gets confusing. Because we have so much material, were not going to get to all of it because I just aded a bunch of stuff this morning. I will not ask really hard questions on the exam this year so if you just kind of follow, think with me, this is more of a thinking thing. Its not the old dog and pony show that I love giving. Okay, my voice is.. !Dilemma- State of the Science [Caufield]So we have a dilemma, I have a dilemma, The state of science is changing radically, throughout the research world but particularly to do with infectious disease. If I could sum it up in a couple of words, it would be next generation genomics and stuff we now have the ability to do. In the old days we would have to take culture of the mouth, cariesput it on agar plates and they grow for 48 hours in an anaerobic chamber. We would come out and pull em out and that was our world. We now see that with 16s techniques that dont involve cultivation, theres a lot more bacteria out there than we thought. So theres three basic paradigms that dominate. Perhaps not dominate. The first is the old Kochs postulates. Now Robert Koch was a German scientist, he was brilliant. He took pieces of potatoes and sliced them, those were the first agar plates. He grew anthrax spores, he grew tuberculosis, tb,.. mycoplasma, micro bacterium. So this guy was actually brilliant, so he came up with some postulates that dominate even today. My colleagues in infectious disease still use Kochs postulates as the driving force. Its probably appropriate for those infectious diseases that come from other sources, we talked about that sonosis (?). So the Kochs postulates,well probably spend more time on how that came about for the last 50 some years. But its now becoming very clear with this next generation of sequencing and other sophistication- this plaque is really a biofilm dental research led the field in biofilms, now its in every aspect of medicine. Ill call it the Bass Becking concept, Ill tell you what that is in a minute. 1934 this paper was written. At the recent meeting of the American microbiology meeting, who wants to go to that? I do. It was in Boston two months ago. Bass Beckings name was involved in that as much as Koch. So interesting. !And then in the case of dental caries, we have this new player that has been known for 100 years called the lactobacillus. Were just making discoveries about that, that now shows us that it may not be indigenous to humans and may be coming form the food that we eat and therefore it would be an exogenous pathogen. Therefore it would be more than Kochs postulates. I know this sounds confusing right now, let me build the case as we go. !Here at Harvard [Caugfield] Okay, so this is what graduation was in 77. I didnt go to graduation. This was an old statement at Harvard every 15 years they pull it out, they dust it off and they

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give it to the graduates. Have of what we teach is correct, the other half is not. The problem is we dont know which is correct. Thats Harvard Medical School. I hate to admit that but I think that we have to acknowledge that as we get smarter and we have other ways of doing things these are going to change. ![Student]: [inaudible] ![Caufield] What school did you go to? Your school was only 30% right, 70% was wrong. Or maybe you went to school where they knew everything. I dont know if you're being facetious or just.Dont side track me. Im on a roll. ![Topics to Discuss] [Caufield] Okay, so heres what Id like to come up with in the next two hours if possible. Dental caries is an infectious disease, it is. The history of bacteria etiology, Im going to give you some of that history, it will be on your board questions, itll be on most standardized test- not necessarily mine but thats what were required to at least tell you what everyone else believes, those other schools, what they believe. And well be talking a lot about organisms like streptococcus mutans and lactobacilli. Kochs postulates, very important they were fulfilled for dental caries it was done 1960, Paul Keyes and that led to the specific plaque hypothesis. Im not going to spend time on that. One of the big factors for the last 15 years waseveryone in this room is infected with streptococcus mutans, if youre not related to each other, I assume youre not and we took your strep mutans, put it on an agar plate, pure culture and we fingerprinted it, each one of you would have a unique stain. So the only people who have the same strain are people who are related on the maternal side. There was a study done last year in rural Alabama, in a 100% African American community that was really isolated and they found that there were surtypes, genotypes of strep mutans that were common. It makes sense because theres probably maternal relationships that go way back. The strain is conserved mother-child, mother-child, mother-child. Generations of time. we have some strains that probably go back 400 years that are absolutely identical and we can show the mother lineage all the way back. !But theres this concept that we all have strep mutans but some people get caries, and other people dont. We all have the infectious agent that we think causes caries, how come some people get it and some people dont? What was invoked was that strains differ in their ability to cause disease- these are called virulence factors. SO when you look at staph aureus, you look at strep pyogenes, you look at strep pneumoniae, anthraces, they all have different virulence factors that are tied to the disease so we spend a lot go time looking for those virulence factors. In mutans, we even did whole genome sequences, still doing so. It turns out that all the mutans are essentially the same. So I take a kid with severe early childhood caries, and I look at a cares free kid. I sequence their entire genome of the bacteria- cant tell the difference. So thats a news break, a lot of

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money has been spent on that topic, its not true. They are finding that same thing out with other infectious agents as well, this concept of virulence. !Lots of money put into these areas- vaccine. There was a hinge decline in application to dental school in the 1980s because the direct of the National Institute of Health said there will be a cares vaccine in the next three years. People were concerned. and the caries research was being done principally in two place Forsythe Dental Institute. University of Alabama, Birmingham, Students were extremely concerned about the notion that there would be a vaccine that would prevent tooth decay. Do not worry, there is no vaccine for dental caries and there wont be. Hate to be the guy giving that lecture, huh? !Probiotics, youre going to read more about probiotics, youre going to sell it. Please dont sell it in your officeYou want to take your probiotics, its better than sugar, its good for you. And then this whole idea of replacement therapy- Ill take your strain of strep mutans and I will genetically engineer it, and Ill give it back to you. What Ill do is Ill knockout your lactic dehydrogenase genes, simple knockout experiments- only takes less than 3 or 4 days, so guess what instead of making lactic acid your strep mutans now makes ethanol. I know someone whos real excited about that. Come up to the lab, give me your strep mutans. Well get you hooked up. Were working on ones that will make meth or something really good, I dont know, how about caffeine? That would be good. !So this was actually still on the market, there still pushing this knockout that was done in 1979 by Jeff Hillman (?) actually one of my classmates; he went to the dark side. So theres still trying to do the replacement where the strep mutans makes ethanol. Great. All the children in the world will be happy about that. I doubt its enough alcohol to really give you a buzz. !Heres Bass Becking. This is going to seem very peculiar, the first time I read this was about 12 years ago. Seems very peculiar because I didnt understand exactly what it meant. ![Baas Becking- 1934] [Caufield] What he did was, he did a study of California lakes, hes an environmentalist and he basically said- think bacteria when you say everything. So bacteria are everywhere and what actually turns out to be a specific ecosystem- the lake he studied in Califronia, or the arctic poles, any of these other environments- whatever the environment is, thats what selects the organisms that live there in that niche. Every bacteria in the planet Earth is in a smallcan get there, can be accumulated, is present all the time, but then when the environment shifts, it selects only a subset of those. A friend of mine at the Marine Biology Institute, Micheal Sagon. When they first came out with next generation sequencing, he took a liter of water from the [inaudible] sea. Pulled out this liter of water, then he applied the 16s next generation sequencing approach, he found 800,000 different

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bacteria species in just a cubic liter of water from the bottom of the ocean. It turns out that most of that was artifact. But still, 800,000 possible what are called otus. And it kind of opened everyones eyes that everything is ubiquitous on the planet. With these bacteria, its just that the ones you see are there just because they are selected by the environment. ![Changing View of Infectious Diseases] [Caufield] So heres a competing hypothesis as of today, the 8th of August. Kochs postulate still dominates in the medical world because yes, theyre working with infectious diseases that are coming from other sources. We talked about that in host parasite there is sonosis from other organisms so Koch was absolutely right in his predictions. But then for those of us and a lot of others working on diseases that might be indigenous diseases, caused by indigenous biota, we may be on the another side of that coin. Ill try to walk in between. I made this about 20 minutes ago, doesnt help does it? Maybe we should go back to the scrolls. ![Kochs Postulates] [Caufield] Heres the problem with Koch, not coke, Koch. What he said is okay I have somebody sick, lets say they have a postula, I dont know, use your favorite. Example, you have bubonic plague and I sample your pus, and I isolate that organ, I then find some animal species like a rat or something and I -well no, first I pure culture it. Remember Koch, he uses slices of potatoes with a sterile knife. Put them on a petri dish, well petri dishes werent invented yet because Petri hadnt come onto the scene yet and then you grow the organism on pure culture. So far so good, Kochs doing great. You then take that pure culture and you stick that organism that you see on that plate into an animal model and the key word here is animal model. Okay, so you took it from a human, you stick it into an animal model. You then look at the animal and see if they die or if they get sick. If they do get sick, you re-isolate the organism and compare it to the original. Simple. There are some problems with this that came up later. For example syphilis which was an obligate disease of humans, there was no animal model for syphilis so streptopnuemiae? ..plus its a difficult organism to work with, very difficult. So Kochs postulates didnt work for every infectious disease. But still, basically, as a general rule what I just told you, you take bubonic plague, you take a postula, you do it, put it in an animal that gets sick, they get pus-sy, re-isolate it, it worksgood. It works well. Ivy league education. !So this was then, it didnt quite work, we replaced it with this guy Barry Eisenbergh who is at University of Michigan when I did my PHD. Im dropping too many names, thats really badreplacedcall it the molecular. So we understood that it was really the genes that cause disease, not the organism thats great. Okay, so thats Kochs. !In terms of dental caries, however, theres a lot of things going on with the environment. And well go back to those slides. Environments select, and Ill go back to the venn

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diagram, carbohydrate-rich diet. HFCS, does anyone know what that is? High fructose corn starch. Japanese scientists 1957, it was brilliant how they were actually able to make glucose and fructose from complex carbohydrates, it was a major change, paradigm shift. ![In regard to dental caries] [Caufield] So well go through these. I dont want to get into specifics. I give you a lecture in enamel hyperplasia later on in your embryology course. Dr. Kim will tell you about drugs that reduce saliva and a lot of you are probably on Prozac, you know what have you. You probably woke up this morning with a dry mouth. That also causes problems withyeah, okay. !So its an infectious diseasesI said like 15 times its an infectious disease but its not contagious. So the old way we used to do this is is say its an infectious transmissible disease. That was based on one organ and transmitting it from mother to child. Caries, per se, obviously isnt transmitted. You dont just have caries in their mouth, kiss somebody and the next day they end up with no teeth. Its not contagious. And its misleading but lets go on. ![As we discussed] [Caufield] So you remember this, the all infectious diseases have this inert relationship. In the case of dental caries its a matter of the host, parasite and the bacteria and the diet. We talked about people who dont have caries but will have, for example, strep mutans, cariogenic bacteria. Maybe, maybe not. ![Venn Daigram- Caries] [Caufield] Theyre called carrier state. Most people are carriers of these organisms, they dont get the disease. We said theres no natural reservoir, theres no animal reservoir, no water or food reservoir, other reservoirs that will hold the organisms for us to become infected, well we thought up until about 6 months to a year ago. We didn't realize that theres another organism out there that is called lactobacillus. And so in the case of lactobacillus, the paradigm is shifting. And again lets just keep developing the theme. Remember when I said that half of what were telling you is true, I dont know which half. Thats why were doing research. ![10-second party line] [Caufield] So let me give you the party line so we can get this over with. This is what the national boards will ask you. So this si how caries is envisioned and has been envisioned for the last 40 years. Acid secretion by cariogenic bacteria, so bacteria make acid, they secrete it onto the tooth surface and the bugs that have been associated with this and are very well engineered to make lots of acid are the ms, mutan streptococci, and lactobacillus. We found a whole bunch of other streptococci, said they can make low pH- these are called homofermenters. Lactic acid by product, its anaerobic fermentation. Most bacteria work by anaerobic fermentation.

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Theres a correlation between dental caries and refined sugar. One to one correlation, almost. More sugar, more caries, up to a point. !University of Michigan did a study, the state was about to put billion of dollars into dental health care for children, at that time this was, 15 years ago. They did a study. They found the kids who ate lots of lots of sugar actually had less caries. Dont tell your patients that. They actually found a cohort of kids who had 250g of sugar a day and didnt get caries. Wow. Okay, but remember my rule, the other rule. Ill show you, not everything is 100%. Basically the correlation is quite good. !Okay, mutans streptococci are members of the indigenous biota. Were going to get into that. They're transmitted with fidelity from the mother to the child, generation to generation. Theyre indigenous, theyre part of your normal, protective, indigenous, co-evolved bacteria. But now we have these other guys, LBs, theyre lactobacillus. !LB, lactobacillus, probably come from the food, were not sure but were pretty sure. Okay, so keep going. This is yourpeople talk about the medical model. So the medical model is, if I can affect the biofilm, if I can get rid of these bacteria, just like helical bactopylori that causes peptic ulcers, if I can just get rid of the bacteria, I can cure the patient. ![10-second party line contd.] [Caufield] People have tried now, including our group for decades to modulate the strep mutans counts in patients. We even treated mothers after they delivered their baby, we treated them with essentially an atomic bomb of anti-microbials to reduce their strep mutans so they didnt pass it to their children. We used chlorhexidine as well. And a lot of other people, probably a 100 papers, published then this idea- treat the mom, the babies are going to have less caries. Great idea, millions of dollars spent, it didnt quite pan out. !So, the medical model is if you can treat the infectious organisms, well we now probably have a tentative list of infectious organisms we might be able to modulate but its not as simple as we thought. We could use the atomic bomb, like iodine, chlorhexidine that kills everything and then expect to kill your target organism, it lacked that target. Removing all the carious material is probably not necessary, but in order to pass state boards or national boards, you have to remove all the caries. But from a microbiological point of view that may not be necessary. And its not me saying that, its in published literature. ![Note: Part of the confusion-] [Caufield] Heres what adds to the confusion when we talk about caries. We have different people giving you lectures on caries, each person sees it from a different view. The problem is not all caries are caries. We think of dental caries as a single disease, its actually a host of diseases, depends on whether its childhood caries, the initial caries

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attack, vs adult. It varies from site to site- pit and fissure caries is very different animal than smooth surface, which is a different animal than root surface. So anatomically, caries is not the same. Even though we just call it caries, the microbiological composition varies wildly from a fissure to a smooth surface, different sets of microorganism. !Theres aggressive caries like what we deal with in the operating room, And theres chronic caries that takes years. So dental caries is not a single disease. So when somebody talks about adult caries in their office, under an amalgam, or a restoration, its not the same as the type of caries we see in very young children, with their primary infection- its extremely aggressive, occurs very rapidly, different pathogenesis. ![Urban Myths] [Caufield] Urban myths Im going to go through this real quick because its going to befuddle and confuse you. We were the first group to show that mothers were the source of strep mutans to the babies, now we dont say mothers, to be politically correct people have said care-takers are the source. Its not care-takers, never was. So the nanny taking care of your kids who has bad teeth, its not the source for your kids cavities. Its nice to blame them, but its all you mom. Its not nanny or father. People use the term caregiver, I dont know what that means. !Oral hygiene, if I brush once a day, I can reduce caries, if I do twice a day I can reduce even more? How about four times a day? [inaudible] No affect on caries at all, zilch, zeroSomebody added flossing. The flossing studies weve done away with a long time ago. But now you see little kids in pediatric dental offices, they got little flossing things going. If youre from the south, you like bbq chicken, you like ribs, I suggest buying some flossSilence, dead silence. Im talking about dental caries. !Think about it a microbial infection, the fact that youre brushing and removing the biofilm, disrupting it? Great. Does it affect dental caries? No. Which sites are the most dental caries prone in the mouth? Pits and fissures. Does a toothbrush clean the pit and fissure? No. !Youre all taking dental anatomy, and you know that a tooth has mesial and distal. Well theres this concavity, and you run a string up and down. Do you think youre really removing the biofilm with that? Second most common site [for caries], is the proximals. So this concavity is right below the contact point. Are you protected fromis brushing/flossing important for preventing periodontal disease? For some of them, absolutely. Would I tell everyone in this room that they should brush and floss their teeth? Please, I beg you. Take baths once in a while too. Its logical and sensical. But if you tell people they are going to prevent caries with this? The data is well established, it doesnt work. !

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They even did this one study in Canada with the boys, young boys 9-15 years of age, they dont brush their teeth. So these kids all had plaque on their teeth, theyre terrible brushers, terrible oral hygiene scores. They had less caries. !I would suggest to most people in the planet Earth today, who have no caries, dont even have toothbrushes. Should you brush your teeth, should you teach it? Yes, you should do it so people have good habits for maintaining hygiene. For all those reasons. But if you tell someone its going to prevent tooth decay-you dont do it. !Putting chemotherapeutic agent on the tip of that toothbrush, it will make a difference, so put some fluoride on it and it will influence. But the hygiene it self does not. Clear? Okay. !We used to think everyone thought, mutans streptococci could be transmitted by saliva. Most infectious diseases are transmitted by droplets. And so, for a long time it was thought thats how transmission occurred. Mothers kissing their babies, fathers/care takers kissing the baby, sharing utensils all of that would be a way of transmitting the bacteria but then transmitting the disease. Thats not true. Thats not how its passed.Its passed mother-child at the time of birth. So all this that you read today, even recently, New York obstetricians giving advice to young mothers they are telling them dont share spoons. If the pacifier falls on the ground, they are telling mom dont put it in your mouth to clean it. Im not going to do that, Ill buy a new one. Dont share utensils- nonsense. Were not talking about some infectious disease that is transmitted via these vehicles. So its not transmissible in that sense. And now a lot of money has been spent treating mothers. If you treat mothers from areas of poverty with young kids, and give them tender loving care and they get restorations, they get better. They do get better, because the mom is more conscious of doing things like reducing sugar for the children. But it didnt work in a microbiological sense. !So youll read in the literature. Is anyone chewing xylitol gum now? You. I saw you move your hand. Youll be my pigeon. Xylitol gum, you know what it is? Xylitol, yes? Do you chew xylitol gum? Sometimes. So if you sold xylitol gum to people, because this is really old stuff- youd want people to think its a new miracle drug and that they could prevent caries with through this. So a group up in University of Seattle went up to Alaska, pregnant mothers- its a real problem with dental decay among Alaskan Native Indians because they have no access to modern facilities, theyre isolated and theyre fed government food. The government food is high in carbohydrates, mostly corn byproducts. The mothers get a lot of tooth decay. This one group had them chewing xylitol gum continuously two weeks before they gave birth to their baby. The idea was that if they chewed the xylitol gum, it would reduce their strep mutans levels. The problem was xylitol, thats why I asked for your personal testimony, causes diarrhea and loose bowels and fladis (?) So I can understand why you didnt want to discuss it further. If you have that much xylitol, you have a real problem with diarrhea because it just goes

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right through. Xylitol was now the new wonder drug, its a good sugar substitute. Xylitol is not metabolized, it doesn't kill bacteria or inhibit bacteria. Thats what theyre pushing right now. ![Caufields Rule] [Caufield] Caufields rule, yup. You saw it. So this begs the question that we had once before, is, I made the theme that the bacteria that caused tooth decay, most of them are indigenous. Co-evolueiton, we grew together. My mutans have been in my family forever. Theyre a part of my indigenous biota, they are part of yours, they protect, they do all these important things. If thats true and we evolve through symbiosis, why does it cause tooth decay? ![Q?] [Caufield] If they have coevolved with us for a long time and now theyre becoming cariogenic, theyre causing disease. I showed you my favorite picture and were selling something over here. And Im buying. What really changed it was our friend Coke-a-cola, but it wasnt really Coke, just sugar. Its really the advent of sugar, sucrose. And when we talk about modern humans, modern humans are 200,000 years old, homo sapiens. When we talk about modern humans like us, were talking hundreds of years. Sucrose, sugar, has only been around in abundance for a fairly short time. ![What environmental change] [Caufield] Its that increase in sugar that has caused the balance to shift f our indigenous biota. There was no sugar on the planet really, prior to the advent of agriculture. We were all hunter-gatherers, we all started the same way. We went to Central Africa Republic to sample the bayaka pigmies, these guys are on a hunting mission. United Nations gave us these Toyota forerunner type trucks, they were amazing trucks. We want to sample the mothers, the babies, we wanted to look at their teeth and get a general idea of their dental health. We also wanted the bacteria from these hunter-gathers that are considered the oldest group of humans on the planet. ![Hunters] [Caufield]Ancestrally these bayaka pygmiesgood bacterial samples. We did bacterial samples, it was interesting when it was time to negotiate, being able to sample pygmies, the tribe leader said Ill let you sample the women and the children, but you cant do the men. I said, boy, whats wrong with that. I have no problem with that. Guys with sharp spears, fine. I dont need to sample the men, I dont want to sample the men. I want mother and child. Two forty pound bags of salt, a huge bag of milky ways and three cartons of Malboro cigarettes clinched the deal. Todays hierarchy, institutional review board wouldn't allow us to do this today. But this was a while back. When we looked at the individual mothers and babies what did we find? Well first of all, there was no toothbrushes or floss. Number two, would you expect them to have lots of caries, no caries or somewhere in between? No caries! Zip. Not a single one. Beautiful teeth, no

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toothbrushes, o floss. Would you expect them to have strep mutans? Yes. All three conditions, some of the most beautiful teeth Ive even seen were among these mothers and children. They had gingivitis, loaded with strep mutans. ![Major Landmarks..] [Caufield] So we did this in biochemistry, I don't think I had this many people. When you look at modern humans, 200,000 years, homo sapien. We did cooking with fire, that was a few laughs. 8,000 Years ago, agriculture was invented by humans, we were able to grow carbohydrates, we were able to form city states, raise armies, and then do all the different things that city states could do- it was because of agriculture. Agriculture brought us massive amounts of carbohydrates. With the advent of carbohydrates, the second part of this is we also learned how to have animal husbandry. Yeah, dont go there. Milk products for example. And youll see differences in the bacterial floor of the tooth, cares and what have you in different cultures. Some cultures cannot tolerate milk, 2/3 of this class probably cannot digest milk. Lactose intolerance. You get milk from your mother. Its because of the enzyme. Once you pass 2 or 3 you lose the enzyme. With animal husbandry we brought in proteins but we also brought in things like milk, or most of those infectious diseases. Remember I told you who were the hosts? Measles, mumps, small pox- there were these animals that we were keeping with us. Pigs-influenza, ducks- influenza. In terms of caries, these events made all the difference in the world. Theres one form of food preservation that we talked about. You use sugar, you have sugar and when you put it together with meat, it will last forever. Most of the stuff in the middle aisles of the grocery store are carbohydrates packed with sugar. Why? The shelf live. Sugar is antibacterial, keeps the food from rotting. Sugar will preserve anything. Theres even sugar used to treat wounds. When I say sugar, I mean sucrose. And spices, we talked about that. ![Caries= Infectious Disease] [Caufield] Dental caries, am I going to say it again? Infectious disease. So what were the original pieces of work that came up with this hypothesis, its an infectious disease? Its an interesting history. I wasnt there for all of it but I knew the people who were involved with it. Because its caused by bacteria, its caused an infectious disease. Thats just definition. This guy in Sweden came up with this concept of germ free animals. So you get rats, hamsters, you deliver them by c-section in an incubator, in a sterile environment. You take the little baby and you put them into a germ free environment, you disinfect everything and you pass that through a couple of generations. You can keep them in a chamber thats called germ free. Totally free of germs, you feed them sterile food. So you get this whole colony of rats, or hamsters, that are totally germ free. Now you go and take that same group- there are some hamsters or rats that get dental caries. Its artificial but you can feed them 75% sucrose and give them some bacteria and theyll develop caries. You take those same rats, you put them in a germ free environment, no matter how much sugar you give them, they get no caries. So you have two groups, a conventional group of hamsters, and the germ free. If you compare the two, this group gets caries, this does not.

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That was the first evidence that was done prior to 1960, with the germ free. The next set of experiments, when the advent of antibiotics became common- penicillin 1945 became more widespread. They were feeding hamsters, rats, and animal models, even humans, antibiotics. And bacteria thought to be causing tooth decay, [if] they were gram positive, you feed them penicillin- the rats, animals, they had no caries. So you take again two groups, one group -penicillin, one group is conventionalized. This group gets caries over here, this one doesnt. Very clear experiments. Bacterial, therefore !Humans. There are some people who have to take antibiotics everyday- children with cystic fibrosis, for example, everyday take a big dose of antibiotics. In the old days, they had tetracycline, caused the teeth to turn black. The childrens life expectancy was about to 15 years of age. If you asked children at that age who were developing a social consciousness, what was the most important thing to a cystic fibrotic child at that time - it wasnt that they were going to die soon, or they couldn't breathe or play sports- the most important thing to them was they had black teeth. That was the number one chief complaint. There were two main centers with cystic fibrosis, some children.these children had black teeth. And it took us a long time to figure out how to actually work without putting in full crowns. !So humans, who take antibiotics for a group of reasons, dont have tooth decay. So, doesnt mean its contagious, doesnt mean its an epidemic- those are terms youll see. So caries is now recently, four years ago, the CDC made a radical change. CDC, Center for Disease Control said dental caries- I told you this, you saw a slide- was perhaps the most prevalent infectious disease of humans. CDC three years ago changed their concept on this and they said that dental caries is a member of the non-communicable diseases. If you look at what those non-communicable diseases are that affect humans- diabetes, obesity, hear disease, stroke- these are the big guys. These are what will kill you today, not infectious disease. Chronic lung disease and asthma. Add to that dental caries. ![CARIES] [Caufield] That was a huge paradigm shift. And theres a lot protect and people making noise about- oh this is an infectious disease, belongs with the other infectious diseases. It doesnt. It belongs with chronic non-communicable diseases. But theyre still fighting and kicking. Youve seen this cartoon. Before the six wise men, they were all blind. Each wise man was brought to the elephant and different parts of the elephant and were asked to describe the elephant. Each of the six were describing the elephant, but each describing different parts. So the guy describing the tusk, he described the elephant as something thatwhatever, use your imagination.The other guy feeling the belly, it felt like a wall. The guy feeling the tailI dont have to go on do I? So if you ask the experts, each one looks at caries from a different point of view, they have a different perspective. ![What is dental caries?]

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[Caufield] This is our disease. And thanks for reminding me, we have to take a break. This is the disease we work with, this is called severe early childhood caries. It is infectious, its not contagious. If you read the public health literature, they say its on an epidemic now. Why is epidemic? Its epidemic not because the bacteria going trough the food chain, its epidemic because the environment has changed. So these kids have cost, we figure its about 2/3 of a billion dollars a year, we spent treating these children with this infectious disease in the operating room. If you ask physicians who are in there in the operating room often times with you, like an anesthesiologist- they say wow this is really severe infection and you agree, it is. Why dont we treat this with some chemotherapeutic agents and what have you? We did. Why didnt it work? Because it has to do with the other factors. ![Severe Early] [Caufield] Well talk about the disease specifically I promise you in embryology. Okay so malnutrition underpins this disease. And again, I said environment. Heres your old venn diagram, do we hate seeing this. Have you seen the new venn diagram? They put a circle of time. Whats that about? Time only moves in one direction. How can time be a parameter? Thats like putting a circle on, say, air, or oxygen. I think what they mean is rate. They mean acute or chronic. But youll see venn diagrams that change, but its really the basic three. It shouldn't be here again, we already did this. I just want to say that lactobacillus is the stinker thats come on board, you know that one. ![Caries-] [Caufield] Okay so, you know what? All infectious diseases including cariogenic ones have to be able to find a receptor and adhere- thats called infection. Thats called colonization. Thats true with every infectious disease. There has to be a specificity. 20% of you have strep pyogenes adhering to the epithelial tissue of your throat but you're not sick. Its only when they accumulate in critical mass, some event occurs where they actually become a critical mass. Thats true with strep mutans and cariogenic bacteria. Critical mass is formed by sucrose and then you have to make some noxious products- prerequisites for all infectious disease. ![From a microbiological] [Caufield] Little tiny lesions form, but caries doesnt just start off as massive front of decay, it starts off as a little, tiny pinpoint to solution based on those microcolony, then they coalesce and form a bigger lesion. And then, after caries begins you have what are called secondary invaders. So the secondary invader that we think of most common, is mister lactobacillus. So if I ask you what the role of lactobacillus was in caries- its a secondary invader. Okay, so well justso heres the guys were talking about- this is traditional old school. Old school as of a couple of years ago. This will be what most people talk about, most people read about, theres some nice review articles. The mutans streptococci is a group. Specific species streptococcus mutans, streptococcus sobrinus. Youll see it in writing in a second. The lactobacilli, up until four, five years ago, because

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we could not type them theres 170 species of lactobacillus, we just didnt know which ones were which. With the advent of next generation sequencing 16s fingerprinting, we can tell you exactly which kind of lactobacillus is in the mouth. ![Known Cariogens] [Caufield] And weve now limited the lactobacillus form 170 possible suspects, to four or five. Only four or five of these are capable f colonizing the oral cavity and causing decay, the 160 something- not true. And then theres another group of bacteria we think are involved in caries. Im not trying to confuse, Im just saying that as we have these tool made available, we have a much bigger group of suspects to chose from. If you ask what the mantra is- what causes caries, particularly in very young children, its almost always related to strep mutans, its almost always there. So strep mutans is a good bet for childhood caries. Whether its true in adults in other forms of caries like root surface caries- its not clear today. Okay, these are the characteristics. You know this before but well just go through them again. Theyre anaerobics so they make acid, some byproduct. Take an extracted tooth, stick it into weak acid, come back a couple of days later, its gone. When you have that high school kid -wants to do a project- Im going to extract a tooth- not allowed to do that anymore. Stick it in a can of coke-a-cola and come back in a couple of days. Coke and Pepsi they have what? Phosphoric acid. And sugar. Come back to goodbye tooth. ![What makes MS] [Caufield] Aciduric means you can make lots and lots of acid and it doesnt screw up your metabolism. Low pH will cause your enzymes to come to a stop. It costs you a lot of ATPs to make your inner cell, or a bacterial cell neutral. You have to export those protons. If youre able to eat a lot of different carbohydrates, it makes you cariogenic and streptococcus mutans, lactobacillus have lots and lots of PTS importers. If you have to get at your carbohydrates by going through a protein rich layer, you need some protease. So theres protease if you're eating dentin, that has collagen, you need a protease Okay, so um, give me one second here. I think we need to take a break. I have to give you a quiz. I dont have to. Its so easy, its like the other one. Okay, dont get crazy, dont start. Let me just get. Okay. So heres the quiz, you get out your little piece of paper. ![Confusion about scantrons] ![Quiz] [Caufield] Okay, so this is question number one, Ill give you two choices- read the question. Okay, you dont see the question yet right? Because I didnt have your attention. Okay, what do these diseases have in common? Im going to give you a choice of two answers, one of the answers is not going to have a mouse or a frog. So look at the diseases- diabetes, have you had any lectures on disease yet? Pathogens? Have you had any pathology, not really right? Obesity, you know what that is. Heart disease and stroke, thats what youre doing to me right now. I feel like a standup- Im dying. Chronic lung

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disease. Atleast you know what the symptoms are, because you have parents that have this. Theres a mothers day sign out there that said, for mothers day buy your mother some bordeaux wine. Why? Because youre the reason she drinks. Okay, asthma. What causes asthma? Caries. Dental caries. These are all grouped together b the CDC as noncommunicable disease. The answer that makes all of those in common is? Answer number 1: all of them are infectious diseases. Answer number two: they are environmentally induced. Are those infectious diseases? All of them? Or are they environmentally induced. Yes, obesity is an infectious disease right? I hope you dont say that. Imagine catching obesity. Anyone like five napkin hamburgers? I had one yesterday. Not as good as I wanted it to be. Put the answer on your scantrons, bring it up here. Take a five minute break. I except over 50% to come back. !![CARIES] [Caufield] Some of the things that I said I know are different than what you think you learned- its not exactly true. Youve learned really good stuff in the past. Other people have different points of view form where theyre at. Im a microbiologist and a pediatric dentist so I didnt point of view. Maybe its not all true, maybe its 50%, mate 35%. My heckler iseveryone should have a heckler. I lost the entire audience. Okay, and Ive been censored, the school has turned my computer off, I cant get my slides us. ![Confusion with the slides] ![Caries Fulfills..] [Caufield] There were some questions that came up. Just remember that dental caries is an infectious disease because its caused by bacteria. All these other things that we, including myself, that we know about other infectious diseases do not apply. For a bacteria thats noncommunicable, part of your human body ,its just gone off the deep end because your diet has changed dramatically. that is the cause of caries. Diet. Look at asthma, environmental air pollution. Hight blood pressure, chronic heart disease. Cholesterolthose are all chronic noncommunicable disease. Dental caries is infectious because its caused by bacteria. If you want to go on antibiotics for the rest of your life, you wont have any dental caries. In terms of oral hygiene, we teach oral hygiene and its important, especially young children, they have to develop motor skills. We want hygiene they way we want everyone to bathe and wash their hands, but it wont prevent tooth decay. Anyone who says it will prevent tooth decay, I want to see the papers. Because there has certainly been enough studied done. And again the Cochrane report just came out, the final definitive thing on flossing- there are only two studies done on children with flossing- doesnt change caries. Do you want to floss, teach flossing to teenagers who have gingivitis, they have puberty, they have their pubital growth spurt, they have inflamed gums you want to teach them how to do that? Yeah, of course. Do you want to put fluoride toothpaste on the brush? Yes, you do, because fluoride has an anti caries effect- its about 20% depends on what study.

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Three weeks ago there was a publication out of Brazil, very good publication by a very good group off epidemiologists- sodium fluoride varnish- no effect. These were high risk children and from Rio de Janeiro, the study is the highest evidence of evidence. Highest degree of evidence there is in clinical trials. Paper just came out, incredibly high quality paper. Do you know how many are studying the paper, talking about it now? She had two inquiries, I talked to her yesterday. Only two people asked about the paper. And yet it shows that one of these modality that were doing all over the place with children, its not effective with kids high at risk. And those are the kids were concerned with. So it takes a while for the practice to catch up with the science. The other part of dentistry is you get paid for procedures. I did too when I had a pediatric practice, I got paid for prophies, or flurried treatment. So did we do it on every kid, every six months? Absolutely. ![Student] [inaudible] ![Caufield] Theres people who tell you not to do the prophy part. Would I recommend 20% reduction in adults in permeant dentition, sodium fluoride varnish has a better effect, its about 33%. So yes, it helps. It helps. Flossing for prevention- periodontal disease only. The arguments being made for small children to learn flossing is because it fosters the kind of habits they will carry throughout the lifetime, you could make that argument. My generation kids were never taught to floss, they dont have the dexterity, you have to do it as a parent. Some of the things we do are just because of habit. When I look at a child, we were in Jamaica not too long ago, I still have some of my old habits that I learned back in dental school. I see a lesion, I want to scratch it with a probe. Im reaching for the probe, we threw the probes away. I like to scratch it. Old habit. Its wrong I cant make this work, the slides. They just went black. Theres a few slides I think youre going to like and you want to see. ![Student] [inaudible] ![Caufield]The reason for the prophy is theyre saying the abrasives, its removing some of that fluoride rich enamel. Sorry, I killed the machine, I dont know how. Im getting hecklers, people leaving. Im taking a beating here, deservedly so..So thats whats going on the prophy part. Who doesnt want to do a prophy in their office? I mean who doesnt want to see nice, clean teeth before you do your exam? It helps me. So we have the hygienist always did the prophy first, cleaned them up and then Im looking at the kid, were all happy. But it does remove the flurried rich layer. Remember you guys are only second year now, you have plenty of time to find your own path. ![Caufield] This is on sodium fluoride varnish out of Rio de Janeiro? ![Student] Are you going to post it.[inaudible] !

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[Caufield] Im vetting it now with some epidemiologist at four different places for them to critique it with me. So we got University of Washington, North Carolina, our own people here and a guy form the UK. These are the top epidemiologists in the country, I want them to critique it. ![Student] How long does it take them? ![Caufield] For them to critique it? Im on the tenth floor, in 1024. Come get a copy. I dont want to make it public. The reason is, I want it vetted first. It is the highest, but I wan other people to tell me that- Im a microbiologist. But that paper just came out. I missed it completely and there hasn't been a single comment made on that paper. Its a game changer. I just talked to the person who finished it last night. Come to the office, Ill give you a copy. ![From a microbiological perpective] [Caufield] Okay, were back in the game. I just wanted to jump to some fun stuff. Because all this stuff, not all of it, but a lot of it is in the air. So we go back to Kochs postulates, I just want to make this clear because this was a fundamental game changer in dentistry. This changed the dental world. This one thing called Paul Keyes, National Institute of Health. And what Paul did is, for the first time, he took a group of hamsters, he gave them caries and it was a pure culture of streptococcus x, turned out to be streptococcus mutans. He inoculated these little hamsters, he raised them, they developed caries. He went back into the hamsters little tooth, isolated the streptococcus that he had put in there, it was streptococcus x, the same one, which turned out to be streptococcus mutans. He fulfilled Kochs postulates. ![Caries Fulfills] [Caufield] Again, let me do it again. Took bacteria from a human carious lesion, pure streaked it, took a single colony of purified, grew it up in broth, put it into the mouths of all these little hamsters, and gave them lots of sugar, did a control group. They grew up, they looked at the little teeth of the hamsters, they had caries. He fulfilled Kochs postulates. Wow. From that day forward, it took ten years to really get Paul Keyes data understood. They did some other experiments with antibiotics, they had hamsters and rats, they did the same experiment. They gave erythromycin to the mothers before she had the babies, theyre called pups. The pups who had the erythromycin, zero caries. The ones that didnt get it- lots of caries. So these were classic experiments, the only problem with these experiments- they were Kochs postulates- the only problem with them was the host-parasite rules. Youre putting a foreign organism from another species, species jumping of humans, into an artificial system, into another animal that never got caries. And then youre jacking up the sugar, and its totally artificial, and youre inducting the caries. Theres no hamster in the wild that gets tooth decay. It doesnt happen. Theres one species of rats that might get some tooth decay, they live in the sugar fields. Caufields rule exception. Animals dont get tooth decay, they dont. But when you

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change the rules and you try to fulfill Kochs postulates and you can strain all of the rules that youre supposed to know or not know. Thats what you get. Thats what happened in 1960, and heres the paradigm that we talk about today. Im mister strep mutans. My mentor discovered strep mutans, Rod Gibbons, who is discovered in my tenure. I love steep mutans, I made a career out of it. Its a great little organism and we find it in all the children with severe caries. But its like 1-5%. Is it really the major driving force or is symptomology of what they get in their diet? So heres Kochs postulates, one bug, one disease, one cure. Mutans streptococci, strep mutans, strep sobrinus, mostly strep mutans causes dental caries. And we have these bullets right, we have mechanical bullets- we do restorations. We thought we could do immunological modifications, we cannot. Vaccine, doesnt work. And we have chemicals. Even today, people are applying large numbers of chemicals to caries active children. Those include things like chlorhexidine, a nasty material. We did it ourselves. We actually got the first IND for chlorhexidine. Iodine, other microbials can be used, but youre changing the whole biota- its not going to work. Okay, so theres youre two guys streptococcus mutans and sobrinus. ![Mutans Streptococci] [Caufield] Im going to reserve my lactobacillus talk because were running out of time- this is our current grant. We have now sequenced lactobacillus from children with severe caries at Bellevue Hospital. It turns out that these things are really important in terms of making a caries go from a moderate type caries to a severe caries, theyre very capable of making lots and lots of acids. In the old days, back in 1950s people thought lactobacillus was the cause of tooth decay, because it correlated almost perfectly with decayed, missing, filled teeth. So you take 200 kids and you do an examination and you do a swab and a lactobacillus count. And then you look at those same kids and you count how many cavities they have. And thats the DMFS, decayed, missing, filled. Decayed on this side, lacto on this side. Correlation is almost perfect, what would you conclude? The conclusion was lactobacillus causes caries. Dependent and independent variables, change them. Put DMF on the bottom, put lacto on the top and say that the DMF teeth is the independent variable. Im talking too much statisticsAnd it turns out that causation, this does not mean causation, it means correlation. They are highly correlated. What this actually means is the more cavities you have, the more lacto. It wasn't the more lacto, the more cavities. Little things like that changes the entire [inaudible]. And theyre easy mistakes to make. Called the ad-hog post fallacy of logic. Okay, so theres youre quiz. !![Lactobacillus spp] [Caufield] I want to talk a little bit about the natural history, is a little bit more fun. Well do this in ten minutes or less. The question is transmission acquisition? If youre target organism in young children is the mutans streptococci- where do they come from? How do they get transmitted? So those studies were done a while back. the principle study was done in University of Alabama, we had 32 people, scientists, in our group so it was a pretty big caries center, so we could do these type of studies. And the question was- as

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peanut says- Lucys going to see the dentist, good luck, Ill give you a kiss. She says dont kiss me, I don't want to catch your cavities. Now, Ive given this lecture, Ive had this cartoon, a friend sent it to me. A couple of years ago I found like 20 people doing the same cartoon, I think that some people actually believe this that this is how infection is transmitted. Through droplet infection, kissing. There was even a column in Ann Landers, University of Alabama, scientists, dentists say, dont kiss your baby- youre passing the bacteria that causes tooth decay, youre passing caries. Totally misinterpreted the results of the study, but it caused a huge PR blitz. Of course, thats not true. You should kiss your baby every chance you get. ![Transmission/Acquisition] [Caufield] There was another study done. We did in China with breast feeding another study did nonbreast feeding and they published that breast feeding could cause caries. Totally wrong. Totally misinterpreted the data. What they forgot to do was look at their study population, the study population- they were very poor. High cab diets, very low standard of nutrition, so they were malnourished. So theres a difference, youre studying apples and oranges. The controlled populated were nourished people who had bottle fed because they could afford it. They had better food, better living condition, better hygiene- hygiene being water. When we did this study, we took 100 children from birth, we did the mothers before birth and after. We just studied them longitudinally for five years and every three months they came in for sampling. So we have this tremendous bacterial profile, still in freezers, still on the 10th floor. We waited to see when the children became infected with strep mutans, when do they become colonized? Well turns out that most of the children become colonized with the organism between 19 and 31 months of age. So this is after teeth were coming in. So the first tooth was the lower incisor, we followed each tooth and we found out that the infection was delayed. So whats going on with that? We called this the window of infectivity that children were susceptible, from this was deduced that if I could protect a young child during those months of susceptibility, they might not have tooth decay. Good concept, 8.5 million dollars, great concept. Unfortunatelyokay so here were the questions that came up. ![Window of Infectivity] [Caufield] Okay, so at two years of age children acquire strep mutans, most of them, some got early, some got it late. Whats going on with the two year old? Theres a change in diet. I used the word caretakers, Im going to take that off. But you have things like nannieswho wants a two year old at home?They get better at three, its called the terrible twos. Whats the first word a two year old speaks? No. Children at two years of age have a lot of ultitis (?) media, they have infectious diseases because their mothers immunoglobulin that they got through the placenta are gone. So theyre susceptible. A lot of sick kids around that time. !Well talk about enamel hyperplasia, thats the major driver, well get to that. Their immune status changes but also a child as they develop from birth to two years of age,

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called first thousand days, their teeth change so they go form one tooth, lower incisor, probably two, to twenty teeth. !{What biological events] [Caufield] So during this period, they have more and more teeth. So what we did- when you map out the infectivity- this is a classic infectious disease approach, you look at your probability of infection based on the year of the child. You see this rapid, exponential increase in acquiring strep mutans. So this we call the most vulnerable period, so whats going on? Two things, number one no mutans if you dont have teeth. Mutans cannot colonize their own cavity, if you dont have teeth. Theres an exception is if the child has a cleft palate and they are wearing a plastic obturator, so they can swallow, they will have strep mutans. If they have hypoplastic, damaged teeth because you're from malnourished or there are some other problems, they will have strep mutans early. But for the most part, the average kids wont. ![Student] [inaudible] ![Caufield] Oh so the placenta, what about the placenta? ![Student] [also, inaudble] ![Caufield] Thats a very insightful question, we thought absolutely, positively could not happen. At the American Society of Microbiology meeting in Boston back two months ago, there was an announcement from the University of Texas that they found oral bacteria in the placenta of mothers. Wow. Earth shattering. I really dont think that if they were in there.Im going to get sidetracked. If you were an aphid, the mother of the aphid puts the bacteria, the indigenous bacteria in the baby. No, Im going to confuse you. That is a breath taking concept, thats its actually in the placenta. They found oral bacteria in the placenta. University of Texas. Oral bacteria, not from anywhere else, from the oral cavity. What the hell are they doing in the placenta? And where in the placenta? I doubt if there were in the artery or vein- they probably-lymphatic tissue. everything Im telling you maybe 50% maybe changed.Its breathtaking. So we contacted the people at University of Texas and Ester Yang, one of our former students is supposed to get the individual..Id like to culture, Id like to.Thank you for getting me sidetracked. We have done a lot of work in evolutionary genetics. Were recapitulating the tree of life, with human migration out of Africa, using strep mutans as the marker. Strep mutans traveled with modern humans 200,000 years ago out of Africa, they took their strep mutans with them. The point mutations in strep mutans reproduce human- youll see this maybe in science. We have Museum of Paris and American MuseumWe sampled in Uganda, we got chimpanzees, we got micots (?) so the tree of life is alive and well. ![Image: S.mutans]

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[Caufield] Anyway, back to this. Maybe I should go further. So heres this infectivity, what drove it? All you have to do is count the teeth and measure their surface area. So as a baby gets more teeth, finally when a certain teeth come in, you have colonization. Those teeth are molars. What do molars have that incisors and canines do not have? Fissures. So you need fissures for colonization, or retentive site. So its the fissures that made all the difference. Now, we thought this meant that the infectivity occurred at that window of infectivity at that time, actually, these children get infected at birth. The way we knew that is, with our cohort of 100 babies, some were c-section, some were vaginal and we looked at the difference and there were huge differences. And from that, the idea that indigenous bacteria transmitted at birth, mutans is just one of them, you dont see it until you have teeth. Theyre there. Where are they? In the tonsils and in the tongue. You know those things we cut out on both sides and all that ring of Waldeyer, we used to cut those out we didnt know what they are for. What they are for is understanding the difference between self and non self. So if a bacteria comes into a babys lymphoid tissue and its from the mother- self. If the bacteria comes from father, or any other stranger- nonself. So in those tonsils, in that tongue crypts, these bacteria are stored until the right environment presents, teeth. Then they come intosame thing with periodontal disease organisms, they are in the tonsils but you have to have puberty for some of the bacteria to colonize the oral cavity. So they just wait til the kids are 11, 12, 13, they hit puberty. You have to have those estrogen compounds, then they can colonize. Everything is everywhere. But you have to have the right environment. And this is relatively new. We have a question over here. ![Student] So will cesarian deliveries have lower strep mutans [inaudible]. ![Caufield] We thought they would bypass the mutans thing, in fact they got infected a year earlier, the mutans, all of them came from the mother. So whats going on with that? After the kids c-section, they do whats called the kangaroo technique, everyone pretty much does it after you do a c-section, you put the baby in contact with the mother. Theres certainly a more direct way of transferring bacteria. So they actually got infect one year earlier, thats probably because transmission was direct, it wasnt vertical in the sense of vaginal delivery. Remember, your ancestors never had c-sections. So the natural pattern of human transfer is through natural birth, and thats how you get coated with your bacteria. You people have vivid imaginations. Our 100 mothers we had, we were there sampling day and night when they were giving birth. We took sloughs, the whole birth process, it was quite an event. Lots of studies I dont know if you can see my picture. You see that Netters rendition of the tongue. So mother transmits these indigenous bacteria, they colonize the lymphoid tissue. Wheres most of the lymphoid tissue in the body? The G.I. tract. They colonize but you dont see them. When the right opportunity presents, that is teeth come in, the window opens and they colonize. Now, the window closes too. So, if you dont get colonized by your mother in those first two years, the window closes other bacteria take their place. So about 15% of people, we cant find mutans. So birth history has everything to do with dental caries. Heres a c-section, the

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fidelity we were surprised. But the DNA fingerprinting showed that the strains all came from the mother, even in the c-section babies. But the c-section babies got colonized an entire year earlier. Why? Probably because they didnt have enough bacteria already present to compete against. Or, they just got it from direct contact from the mothers post c-section. We really dont know. ![Initial Colonization of MS] [Caufield] One interesting aspect that to this study, that other people who have tried to do this study- all the c-section mothers get a whopping dose of antibiotics because they have a surgical procedure done. So every obstetrician who does this procedure gives them antibiotics, that actually changes everything. What has yet to be explored is this whole concept of antibiotics occurring after birth, it actually changes some of the gram positive, we dont know how. Put it in the back of your mind because mothers who get antibiotics for group b strep,their kids didnt really have many caries. Thats going to confuse us, so erase that. The study that we have this week, is with adopted children. I just told you the bacteria you have at birth comes from the mother, what if youre adopted? Does the babys strep mutans look like the mother, somebody else, or the father? Stay tuned, theyre doing the fingerprints again today. If I ask people in this room, how many are adopted? And I ask you if you have cavities? I did this at University of Alabama Dental School. Everyone who raised their hand and said they were adopted didnt have caries. Is that a good study, I dont think so, probably skewed. Think about it. I wont ask you if you were adopted. Probably, all of you. Youre probably all clones, youre dental students.Ive exhausted my humor and your humor. !Heres your last parting. You know where babies come from right? The stork brings it to your house? Is that common mythology.theyll tell young kids that your baby brother came from this stork. Who invented this myth? I dont know..so when the stork brings the baby, theres some important things the mother must do. In a pure Darwinian sense, what is the mothers most important job for the preservation of the baby in hostile environment, Im not talking about New York City, a hostile environment with infectious disease all around. In order to perpetuate the species, the human, in order to give that baby every chance to survive, because most babies dont survive, the mother must do three things. Number one, she has to have half her chromosomes, have to be pretty good. How do we know that theyre pretty good? She survived. So if a mother can have a baby, shes already put on the fat, survived and shes healthy. Shes already made it to childbearing age, shes healthy. Whats the most important thing for her to do? Find a man. Guys wake up. Womans looking for a man to perpetuate the species. What is she looking for? A guy with good eyesight who can throw a spear and kill a giraffe. Well, thats none of us, sorry, those people been extinguished. Someone has a BMW, is a dentist, can read books, natural selection thats what you want to pick. So now, the child gets good chromosomes, good genes. The mother has to give her immunoglobulins to the baby, those immunoglobulins got that mother that far. So whatever that environment is, for example, surrounded in yellow fever, other infectious diseases-cholera- shes

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survived, she has immunoglobulins that have protected her in this environment. Her job is to et those immunoglobulins to her baby. How does she do that? Placenta. IgG. Have you done immunoglobulins yet? She sends all those immunoglobulins to the baby. Breastmilk- igA, igM. This baby is loaded up with mothers immunoglobulins, only mothers. Does the baby get immunoglobulins from the father? I dont think so. Its not his placenta. !So you picked this good mate with half of the chromosomes, get rid of the guy, dont need him anymore. Just you and the baby. So baby only gets immunoglobulins from the mother. Heres the other thing that the mother has to do for that baby to survive- she has to give her bacteria to that baby. She has to coat with those bacteria. Those bacteria that come only from the mother have to be matched set with those immunoglobulins. So mothers immunoglobulins, mothers bacteria- match set. This is whats called self- self recognition.thats mothers job. And to do that, things have to work out. Thats nature, Darwinian pressure. When this gets upset and one of these things is permeated and not done, then we have problems. Thanks for staying, I apologize for not putting this together better for you. See yousometime.

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21/22: Microbiology of Dental Caries