Dr David Merrill First Principles of Instruction Review

Season 2 | Episode 6

>> Joe: How-do-you-do once again, and welcome to the Merck Manuals Medical Myths podcast, where we fix the record direct on today'southward about talked about medical topics and questions. I'thou your host, Joe McIntyre, and, on this episode, nosotros welcome Dr. David Murchison. Dr. Murchison is a clinical professor in the department of biological sciences at the University of Texas at Dallas. Only, we have him on the podcast today to talk virtually his expertise in dentistry. He'south been a practicing dentist for more than than twoscore years, and besides spent more than thirty years in the Air Force doing comprehensive dentistry and a lot of dental education, every bit he says. He's also a professor at the Texas A&One thousand College of Dentistry in the Department of Orthodontics and the Department of Comprehensive Dentistry. Dr. Murchison, thanks for coming on the show.

>> Dr. Murchison: Thank you, Joe. Looking forward to it.

>> Joe: Now, many of us, or all of us ideally, should have some feel in visiting a dentist, sometime in our lives or for one reason or another. But, as you told me before we started recording, Dr. Murchison, we shouldn't just see our dentist just when our teeth injure or only when they're bothering us. Can you explain why that is and how frequently nosotros should exist seeing our dentist?

>> Dr. Murchison: Well, Joe, dentistry has actually prided itself on being a profession that really practices prevention. And, so, in order to foreclose, you need to go in even when your teeth aren't hurting. It allows for a clinical examination, first of all, because we're not only looking at cavities in the teeth or gum illness, as we'll speak about a little bit after, only any growths or tumors or unusual findings that we can find, and, over again, prevention works all-time when you lot observe things early on. And, so, a preventive practise in dentistry is the best manner to become, and, so, if you lot've waited until the teeth start to hurt, that usually ways that it'due south progressed to the betoken that some intervention is going to exist necessary, whereas, especially with gum disease and gingivitis, just a niggling flake of hygiene tweaking, a little bit of better cleansing of the oral fissure, volition certainly help and will reverse gingivitis, and in some cases these days, fifty-fifty reverse very small, what we term small enamel white legions, which is only a lilliputian chip of demineralization, and then you can really prevent cavities by the awarding of some topical fluoride or some fluoride varnishes or very, very pocket-sized dental restorations before they get big and really cause the teeth to injure.

>> Joe: Now, you lot mentioned mucilage disease there. I call up this is something we've seen or heard of for a long time. Is gum disease something that's rare, not something necessary that people demand to worry about, or is information technology more common than people retrieve?

>> Dr. Murchison: Much more than common than people remember, and gum disease actually, in most of the Western world and, actually, probably, beyond boundaries, is, past far, the leading cause of molar loss afterwards the historic period of belatedly-twenties, mid-thirties or so, and it has to exercise with the loss of bone that accompanies periodontal disease, periodontitis, which is an inflammatory affliction, and, so, gum disease is not rare. In fact, it's a very, very common occurrence, and, as I said before, as we age, it becomes the most common cause for the loss of teeth.

>> Joe: At present, I accept seen some fodder on line that says gum disease may not just be a concern only for your mouth. Is that true?

>> Dr. Murchison: That's very truthful. There's been a link between, really, gum disease and some cardiovascular problems considering it's a affliction that's set upward with inflammatory aspects. And, then, inflammatory aspects from cytokines and other kind of localized that can become systemic effects. It can actually set up equally a potential for cardiovascular problems. The second matter is it'southward exacerbated by specific systemic problems, and, so, if somebody has a compromised immune system by, say, something like diabetes, leukemia, it advances the progression of the periodontal disease or the periodontitis or the gum disease. And, then, all of these things need to be taken into account, and that's why your dentist takes a very thorough medical history as well as doing a clinical evaluation when you go in for your annual examinations.

>> Joe: And so, one myth that we've also seen a lot online, and, I'm sure, many of the states accept heard some fourth dimension or another when we were kids, is that chewing sugar-free gum can exist either a substitute for flossing or, at worst case scenario, a substitute for brushing your teeth. I'm assuming that's not the example, but can you explain why?

>> Dr. Murchison: That's certainly not. Now, saccharide-free mucilage is certainly preferable to sugared gums considering it doesn't let the oral bacteria to feed on the sugars, and they tin can exist glucose or sucrose or all kinds of the sugars that break downwardly to cause acids that actually are the cause of tooth decay. Sugar-free glue is non a substitute for flossing because it doesn't reach those especially difficult-to-reach areas which are betwixt where the teeth run into each other, or what are known as dental contacts, and that'southward where food debris and plague tends to collect, and, then, the flossing is able to become in there, remove those bacterial colonies which are dental plague, and the flossing can get in in that location where glue cannot go in between the teeth.

>> Joe: Now, along that same vein, are diet sodas technically better for your teeth because they don't have saccharide in them?

>> Dr. Murchison: They are, but, again, everything in moderation. Nutrition sodas, because they have saccharin or sucralose or other dissimilar kinds of artificial sweeteners in them, as opposed to sugars, they don't feed the bacteria. Merely, the problem is, they're carbonated and they're acidic, and, and then, it'south the acids that tend to piece of work as well, and, and so, we see a lot of people, when I was in the Air Force, we had a lot of people that had jobs where they either had to listen in for a long fourth dimension or they were monitoring things, and they sat there with a carbonated drinkable, a soda, a cola, and they were sipping on those all day, and it has to do with the acids working on those teeth all day long. And, information technology's the aforementioned thing if you lot accept sugar in your coffee, and y'all're sipping on the coffee all twenty-four hours long, and, so, information technology'southward an exposure duration, and your saliva just can't buffer information technology for that long, and then those people tend to accept a lot of dental cavities because they accept acids working on the teeth all day.

>> Joe: Then, it'due south not merely carbohydrate that's the cause of teeth disuse, but it's acids, carbonation and sugar that combine to crusade this effect?

>> Dr. Murchison: Correct, and, again, peculiarly for people, let's say, a medically-comprised person that has had some kind of head and neck cancer, that has gone through radiations, and the radiation is diminished or completely taken away their saliva menstruum. Those people are at high risk for dental cavities. And, it'due south because there'southward no buffering effect that's left in the saliva. The saliva also contains some semblance of fluorides, and, then, again, saliva buffers that, but, if you're continually challenging that with a very depression-PH, carbonated potable, a sugar-contained beverage, as well, that forms the acids from the leaner, you're going to overcome the protective aspects of the saliva and the fluoride that yous use in your toothpaste and start to take those demineralized areas that class cavities.

>> Joe: Whether you're a parent or a seasoned professional, a medical student or a caregiver, the Merck Manuals has the right medical information in the all-time format, and information technology'south always free, easy to access, and readily available for yous.

>> Joe: Let'southward talk a piffling flake well-nigh how nosotros can forestall some of those cavities. Ane master key aspect of that, I'm certain, is brushing your teeth. Now, when information technology comes to brushing your teeth, does it matter what time of time you practice brush your teeth?

>> Dr. Murchison: Every dentist, I think, will recommend brushing subsequently meals, and that helps to remove food debris also as interruption up the bacterial colonies, the plague that's in your teeth, but, certainly, in the forenoon, before or afterward breakfast, depending on what you prefer, and then right before y'all get to bed at dark. At least those two times a twenty-four hour period, twice a day brushing, volition break up that dental plague that we were talking about equally the bacterial colonies that harbor those bacteria that can cause both the gum problems, the periodontitis or the gingivitis, as well every bit the dental cavities, the dental caries there. So, by breaking upwards those cavities, you're able to practice that.

>> Joe: At present, I've e'er been told growing up that I should have a soft-bristled toothbrush, but yous would think that having hard bristles may be more likely to remove some of that plague and debris that's in your teeth. Is that not actually the case?

>> Dr. Murchison: No, that's exactly opposite. The hard beard have been shown to really crusade a lot more damage, and the soft bristles, ii aspects: one, they're non as abrasive when you lot're using them with the toothpaste, and that's what you're doing, is the beard themselves are taking the abrasive portions along with the sudsing portion, which is a sodium lauryl sulfate, it'south kind of a detergent in our mouth, but, in terms of actually the toothbrush bristles themselves, the soft beard get up under the mucilage tissue and remove the plague meliorate. The hard bristles tend to exist more annoying, and they don't splay, or move in under the gum tissue as well. They tin can also cause impairment to the gums, and then we don't want to exercise that. We don't want to crusade any recession, which is an actual moving of the gum tissue away considering of either a habit, a tooth castor habit that's as well hard, or a fingernail habit or somebody has a bobby pivot or something like that that they employ, and, so, there are a lot of pernicious habits that hurt also. Simply, hard bristles are not practiced. Soft bristles are practiced, and specially for children.

>> Joe: Now, you mentioned brushing hard. Is in that location a recommended pressure that someone should use when brushing their teeth to avert brushing as well difficult and causing some of that recession that you mentioned?

>> Dr. Murchison: Joe, what you lot really don't want to do is merely a back and forth motion. It's more of a rotary, or kind of a roundabout motion, at almost a forty-v degree angle toward the glue tissue, and that allows for those bristles to move upward into what'south known as the sulcus, the gingival sulcus, which is the fiddling infinite between the glue and its zipper to the tooth there. And, and then, by doing kind of a back and forth move every bit opposed to a tremendous corporeality of bushing hard in a straight force, by using that rotational move, the circular type of motion, you're able to remove a lot more of the plague and yous don't cause the same kind of bug with the enamel.

>> Joe: Now, let'south switch over to something that people await up online, whether it's in the Merck Manuals or just simple searches online all the time, this idea of how to make their teeth whiter. Everybody wants to make their teeth whiter. We've seen remedies such every bit lemon juice on your teeth, charcoal, coconut oil. Are whatsoever of these quote-unquote natural remedies helpful for whitening your teeth, or are they quite exactly the opposite and actually harm your teeth?

>> Dr. Murchison: Lemon juice specifically, and we actually see a lot of that downward in Texas. In that location are cultures that tend to actually suck on lemons, and you become a lot of acidic erosion of the enamel of the molar. Enamel is made of calcium and phosphates, a material called hydroxyapatite. And, the problem is, when yous have a very acidic material similar citric acid that comes from lemon juice or oranges and things like that, it actually erodes as an erosive agent for the enamel of the teeth, and we meet a lot of the enamel loss. Y'all mention charcoal. That has not been shown every bit beingness as efficient in removing the plague of the teeth, and, secondly, it doesn't take the improver of fluoride, which is really, actually important from a preventive standpoint. The terminal thing y'all mentioned, kokosnoot oil is used again in other cultures, specifically known every bit a pulling technique, where you place coconut oil in your mouth and so classy and effort to movement it betwixt the teeth there to try and help remove the dental plague. The problem is nigh of that requires 10 to fifteen minutes of swishing your mouth. Well, I've had children, now I have grandchildren. Trying to get them to castor their teeth for 5 seconds, much less ten or 15 minutes of this pulling, it'due south very, very difficult. So, I can tell y'all the American Dental Clan has no research that shows that there is a preventive attribute or a better aspect from the use of coconut oil lonely, and, certainly, as an adjunct, they haven't shown that it's detrimental, but brushing and flossing, twice a 24-hour interval, with fluoridated toothpaste is the recommendation from the American Dental Association.

>> Joe: Is it true that when your teeth are whiter, they're healthier?

>> Dr. Murchison: They're not healthier, Joe, but, what they have done is removed organic stains. Then these are the stains that come from coffee, wine, unlike kinds of fruits and vegetables, beets and things like that. And, so, the hydrogen peroxide actually removes those stains. It'south a transient kind of thing. Information technology's temporary. It lasts for a trivial while, and, certainly, there are some techniques, besides, if you go to a dentist and they practice an in-office bleaching, some of the dehydration that happens to the teeth will make them appear brighter as well. But, these are relatively safe, again, moderation is the key. And, so, if you bleach, either a home bleaching or an office bleaching regimen, that'due south followed in the recommendation from the manufacturers' materials, you tin whiten those teeth. But, again, it's a transient kind of thing. And, to continue that same whiteness, you're going to take to either alter your diet, away from a lot of different things, or get this washed on a periodic basis.

>> Joe: Now, we've talked well-nigh the importance, obviously, of brushing your teeth. Can yous become a fiddling into flossing? Why it's valuable, why it'southward important and how information technology helps united states remove some of that plague that brushing may miss?

>> Dr. Murchison: Flossing gets between the teeth, and it gets under the mucilage tissue, and, when done correctly, it breaks up the bacterial plague, and, so they don't have the chance to colonize down in that location. And, for cavities, by breaking up the bacteria, they haven't had time to demineralize the enamel of the tooth. And, so, over again, they accept to take in sugars, take in different starches and things to break them down into acids that cause the dental cavities. And, so, the floss only breaks them up and then allows, again, used in conjunction with brushing, the removal of that dental plague. And, so, by using flossing, by having the dentist go downwards and remove some of the calculus or the tartar, which is the harder deposits of the teeth, you've removed some of the nooks and crannies also that tend to form down in that location. So, past preventing that calculus or the tartar, the floss, again, is removing the plague and so it doesn't harden to form an surface area, again, that then those anaerobic bacteria can class underneath to actually cause the progression from gingivitis to periodontitis or the glue disease.

>> Joe: We've seen this a lot online. I'm sure it's not necessarily truthful, but I want information technology to come up from your mouth. Does flossing create spaces betwixt your teeth?

>> Dr. Murchison: Flossing does not create the spaces of the teeth. What usually happens is we get drifting of the teeth, and this is especially prevalent in patients that have astringent periodontal disease. And, they lose bone back up, and the teeth showtime to move and, specifically, in ways that the oral cavity tends to role. And, so, as y'all motility your lower jaw frontwards or a protrusive kind of move, it can actually piece of work on those upper front teeth, and you start to class some spaces in at that place. So, flossing is not the crusade of that. Information technology'south the loss of os.

>> Joe: Now, it can be like shooting fish in a barrel when someone is flossing to see some blood, perhaps in their spit when they're cleaning out their mouths. Is that a reason to stop flossing, or, if y'all're brushing your teeth and you lot come across blood, to stop brushing?

>> Dr. Murchison: The blood is showing that there is an inflammatory process going on, and, so, the body reacts to inflammation in a couple of different ways. It sends more blood supply in that location to send some of the kind of white blood cells and lymphocytes and things that tend to fight inflammation, and, so, offset of all, you start to get a redder looking area, and that's why gingivitis tends to have some ruby gums. You tend to accept edema, or a swelling, in that area. And, so, the gums tends to exist swollen as well. And, finally, if left long enough, you tin can actually get little abscesses in in that location, and, then y'all can really get some purulent, or some puss, coming out of those areas, and that, again, is unremarkably an indication that periodontal affliction has started with the loss of bone associated with that equally well. If it's kept in gingivitis, again, and then if information technology's bleeding, that shows you need to spend a little more time non brushing harder simply a little more than thorough to remove the bacteria, and you'll run into that, with continued flossing in that area, and continued brushing, taking a little fleck more time, and, if necessary, having the teeth cleaned to remove any of the tartar or the calculus in that surface area, you'll see the bleeding finally reduce and and so, hopefully, go away.

>> Joe: Now, speaking from personal experience, a few years ago, I switched to sensitive toothpaste, sensitive teeth toothpaste because I was dealing with some sensitivity in my teeth. Is tooth sensitivity but a effect of enamel loss?

>> Dr. Murchison: Joe, actually non. It tin exist associated with enamel loss, but it is often associated with a little bit of gingival recession, and, so, it tends to exist merely as the patients are moving from, say, the late twenties to the thirties to the forties, and y'all're starting to get a little bit of gingival recession to the gum tissue moving down towards the root of the tooth, and where the enamel and the cementum run into at that place, if you have an ambitious brushing manner, if you've had a cavity in that area, or, more frequently, if you lot tend to have what are known as abfraction lesions, where you've formed kind of a V-shaped area where you've lost some of the cementum due to some motion of the tooth, some flexing of the tooth in that surface area, you've now exposed dentin. And dentin is a vital structure underneath both the enamel and the cementum, and it's made upward of little tubules. And those tubules are what causes the sensitivity considering they are fluid filled, and the movement of that fluid stimulates some nerves that are down about the nerve of the tooth itself. Now, well-nigh ten per centum of the population is born with a gap betwixt the enamel and the cementum. And, and so, if y'all happen to be one of that ten percent, as soon as you get a little flake of gingival recession when you drinkable some iced tea or you lot drinkable something sweet or drinkable something very hot, information technology causes that stimulation of the dentin. And, so, there are a couple of different ways to handle that. You can put a restoration on that; that'south invasive. You tin apply a desensitizing agent which works for a little while. Or you lot can utilize, every bit you but spoke about, a desensitizing toothpaste, and nigh of those comprise potassium nitrate within a toothpaste or some types of gels. Some bleaching agents fifty-fifty have some potassium nitrates to endeavor and reduce tooth sensitivity. But, by using that, it actually acts at the source of the nervus near that tooth, but, the affair is, it takes a certain corporeality and a certain amount of time of that sensitivity toothpaste. And, so, if you get to the dentist, and the recommend that, and you inquire for that considering of tooth sensitivity, they'll usually say give it four to half-dozen weeks because it takes time for the actual activity of the potassium nitrate to work on the fretfulness themselves.

>> Joe: Alright, as we kind of wrap up hither, Dr. Murchison, I want to talk near wisdom teeth. I had my wisdom teeth taken out probably around four years ago, relatively painless process and no issues afterwards. Tin you lot explain to our listeners why people get their wisdom teeth out and what perchance some of those reasons would exist?

>> Dr. Murchison: Information technology's an individual telephone call for each patient. So, you'll exist interested to know, Joe, that wisdom teeth tend to be the teeth that tend to be missing at nascency for quite a few people. Then, some people never have whatsoever wisdom teeth, or they're missing ane or ii or sometimes all 4. Simply, they're the most commonly missing teeth, and, so wisdom teeth aren't required for y'all to be wise. I don't even know where that moniker came from. Only, wisdom teeth are third molars, basically, and, actually, you'll find that sometimes wisdom teeth don't take to exist taken out. Sometimes, patients have had orthodontics in the past, and they've lost bicuspids as the orthodontist has moved the teeth around, and they'll take room in their mouth for those wisdom molar. Some people have large enough jaws that the wisdom teeth can come in and not be covered by a portion of the mucilage tissue back at that place or cause whatsoever kind of chronic inflammatory procedure back at that place. Unfortunately, for many people, the wisdom teeth come up in at an bending, and, so, they're never going to erupt, and then they cause, at that point in time, a real potential problem by potentially being trouble to the molar in front of them, the second molars which nosotros really need for chewing efficiency, and, so, if the dentist or the oral surgeon that is evaluating the patient for removal of the wisdom teeth decides that the angle of these teeth, their position, is going to become a problem, or if the tooth is never going to erupt and at that place'll be a continuous inflammatory process and, potentially, and infected process back there because bacteria loves to hide nether these footling flaps of tissue that cover some of the lower wisdom teeth back there. And the trouble is the upper wisdom teeth can sometimes seize with teeth on that fiddling flap, and information technology's called pericoronitis, which is peri-, around the crown, -corona-, of the wisdom molar down on the bottom, and, so, at that place is a constant kind of inflammatory process down in that location, and, so, again, you don't want infection in the oral fissure, and that'due south what can happen over fourth dimension. Then, if you lot maintain wisdom teeth in your mouth, you need to be evaluated over fourth dimension with dental 10-rays that show that tooth to make sure that nil is being stirred upward by having that tooth remain inside the os over time.

>> Joe: At present, I'm sure we've only just touched the tip of the iceberg when it comes to dental questions or dental myths. We merely have about a half 60 minutes here. So, if someone has a question most a dental issue, a dental question, a myth that they've heard that they desire clarified, Dr. Murchison, where should they go for those answers?

>> Dr. Murchison: Well, preferably, Joe, they're request their dentist as they go see him or her on a 6-month or an annual basis to be evaluated, and, then, again, the dentist is looking at your specific situation, and, then, they'll be able to give you lot your specific answers. But, if they're going online, certainly the Merck Manuals accept some great dental authors that write the chapters on some of the things that we've talked about today. They talk nigh dental emergencies. They talk about periodontal illness. They talk nearly pediatric dentistry and eruption of teeth and things like that. So, at that place'south a plethora of cognition out there on the Merck Manuals at MerckManuals.com. The American Dental Association provides a lot of free information, and a lot of the dental manufacturers. So, you lot go to, again, I have no beholding to whatsoever of these manufacturers, merely if you get to any of the toothpaste companies that are out there that provide oral hygiene, you can get some information about the ingredients in there for whitening your teeth or fresh breath, for sensitivity and things like that. But, the American Dental Association will provide a lot of information on specific topics, and they use an show-based science arroyo equally well, and, so a lot of the, quote, myths that are out there, whether it's a material that's used in your mouth, whether it'due south some type of potential allergen that's out in that location, the American Dental Association is a great identify to see that.

>> Joe: Well, Dr. Murchison, cheers again so much for joining us. I think this has been a super helpful conversation. I know I've learned a lot about dental health and how to brand certain my teeth are protected and as salubrious as possible.

>> Dr. Murchison: Joe, information technology'southward been my pleasance to talk to y'all, and I appreciate you asking me on today.

>> Joe: And, I'll leave our listeners with something equally nosotros say every time we exercise at the Merck Manuals

>> Dr. Murchison: Medical, and dental, knowledge is power. Pass it on.

>> Joe: Thank you so much.

lupoheireass.blogspot.com

Source: https://www.merckmanuals.com/professional/news/editorial/2021/04/13/23/11/podcast-dental-myths-with-dr-david-murchison

Share this post