Chapters
Why Dentists Are Interested in Your Saliva
[00:00:48 – 00:07:10]
Saliva does far more than keep the mouth moist. It neutralises acid, washes away bacteria, and delivers minerals that help repair early enamel damage. When its quantity or quality drops, the risk of cavities, erosion, gum disease, and infection rises significantly.
Saliva testing can measure how much saliva a patient produces — both stimulated (triggered by chewing) and resting — as well as its acidity and buffering capacity. Even the presence of specific bacteria, including those linked to heart disease and Alzheimer’s, can be identified through saliva samples.
Whilst these tests are not currently routine at OptiSmile, falling costs and advances in AI mean targeted saliva diagnostics may well become part of everyday dental care in the near future.
DNA Testing and Your Genetic Risk for Gum Disease
[00:07:26 – 00:09:12]
Not everyone responds to plaque in the same way. Some patients develop severe gum disease with relatively little bacterial build-up, and genetics can explain why. A gene variant known as IL-1 (interleukin-1) has been linked to an exaggerated inflammatory response to bacterial challenge.
Knowing a patient carries this marker allows a dentist to personalise their prevention plan — more frequent professional cleans, targeted antibacterial therapies, or a referral to a periodontist. As the episode puts it, genetics loads the gun, but behaviour pulls the trigger.
Ultimately, the fundamentals remain the same regardless of genetic risk: floss regularly, attend professional cleans, and address any lifestyle factors such as smoking or poorly controlled diabetes.
Identifying Bad Breath Bacteria Through Saliva
[00:09:19 – 00:10:58]
Saliva and plaque samples can be tested to identify the anaerobic bacteria responsible for bad breath — those found on the tongue or within gum pockets. Pinpointing these bacteria in theory allows for more targeted treatment rather than trial and error.
In practice, however, consistent oral hygiene habits — tongue scraping, flossing, ensuring gums do not bleed — address the root cause in most cases. Prescribed chlorhexidine products such as Curasept may also be recommended, with caution around over-the-counter alternatives that can stain teeth.
The IL-1 Marker and Implant Risk
[00:11:08 – 00:12:00]
The same IL-1 genetic marker that signals heightened gum disease risk also has implications for dental implants. Patients who carry this variant may be more prone to inflammation and bone loss around an implant over time.
For patients with a history of gum problems, a referral to a periodontist — who may carry out genetic testing and tailor a closer monitoring schedule — can help safeguard long-term implant success.
Buffering Capacity: How Well Does Your Saliva Handle Acid?
[00:12:08 – 00:13:48]
Buffering capacity refers to how effectively saliva can neutralise acids in the mouth. A low buffering capacity means the saliva struggles to counteract dietary acid, gastric reflux, or acidic drinks, leaving teeth more vulnerable to erosion and decay.
Testing buffering capacity is straightforward — samples of both resting and stimulated saliva are collected and analysed. For younger patients in particular, early testing could motivate positive changes: drinking more water, chewing sugar-free gum, and improving diet before damage accumulates.
Using Saliva to Guide Antibiotic Selection
[00:13:57 – 00:14:36]
In specialist periodontal care, samples taken from within gum pockets — known as crevicular fluid — can be cultured and tested to identify which bacteria are driving an infection. This allows the clinician to select the most appropriate antibiotic rather than relying on a broad-spectrum approach.
Whilst not a routine procedure, this type of targeted testing is particularly valuable in complex or persistent cases where standard treatment has not resolved the problem.
Cost, Accessibility, and the Road Ahead
[00:14:47 – 00:16:43]
Saliva and DNA testing remains relatively expensive for most patients, particularly when paying out of pocket. However, selective use — for instance, IL-1 testing in a patient with unexplained aggressive gum disease, or bacterial culture in a stubborn infection — can offer genuine value when the insight changes treatment decisions.
The trajectory is towards greater accessibility. Just as COVID rapid tests moved from clinics to chemist shelves, at-home saliva diagnostics capable of flagging gum bleeding, bad breath bacteria, or blood sugar levels may become a routine part of personal health monitoring within the next few years.
Personalised Dentistry and the Future of Diagnostics
[00:16:44 – 00:19:59]
Combining saliva flow data, buffering capacity results, bacterial profiles, and genetic markers builds a detailed picture of an individual patient’s risk — moving dentistry from a reactive, fix-it model towards genuine prevention. This kind of evidence can also be a powerful motivator, making it easier for patients to understand why more frequent check-ups or specific hygiene habits matter for them personally.
Research is already underway into saliva-based detection of systemic conditions including diabetes and certain cancers, with experimental tooth-mounted biosensors capable of streaming blood sugar readings via Bluetooth. Whilst not yet in clinical use, these developments signal how closely oral health and general health diagnostics are converging.
The collection process itself remains simple and non-invasive: chew a piece of wax, spit into a small cup, or swab the inside of the cheek for a DNA sample. No needles, no discomfort — just information that could shape smarter, earlier care.
Transcript
[Eon Engelbrecht – E-Radio-SA] (0:04 – 0:37)
Welcome back to Save Your Money, Save Your Teeth, the podcast where we make dental science practical,
useful and easy to understand. Now today, Dr Clifford Yudelman from OptiSmile joins us to talk about saliva
testing and DNA diagnostics. Now it sounds futuristic, but it’s really about something very simple, just
understanding a patient’s risk before problems become expensive, painful or even difficult to treat.
Dr Yudelman, welcome back.
[Dr Clifford Yudelman – OptiSmile] (0:37 – 0:47)
Thank you, thank you. Nice to be back and looking forward to today’s episode. It will probably be quite a
short one, but let’s see how we go.
[Eon Engelbrecht – E-Radio-SA] (0:48 – 0:53)
Now Dr Yudelman, why on earth would a dentist want to test my saliva?
[Dr Clifford Yudelman – OptiSmile] (0:53 – 7:10)
I like the way you put it. I agree with you, why would a dentist want to test your saliva? But since we’re
talking about that, so look, I was testing saliva for patients when I was in Perth. We’re talking, I’ve been in
Cape Town 11 years, and I was doing saliva testing back, I went to Perth in 2002, and a couple of
companies came out with these saliva tests and it was a great thing to do for patients. It was a whole little
kit, and the test itself was quite expensive for us to purchase, and then obviously it took time. We had to
book an extra half an hour.
So when you decided to test someone’s saliva, you weren’t doing it for free and they were paying for it, and I
think it’s still sort of the case when it comes to the types of testing we’re going to talk about in this first
question.
One of the things is, saliva is very diagnostic, similar to having a blood test. There are so many things that
always amaze me. I just had some blood tests done and you’re only getting maybe five or 10 or 12 tests
done, and there are literally a thousand things you can test in the blood, and saliva is very similar.
But the type of testing that we were doing back then, and I’ll just have to say off the bat now that there are
some dentists that are starting to get popular again, and there are even some practices in Cape Town that
are promoting different types of tests that we’ll talk about today, but I don’t personally do any saliva testing in
that sense like we used to in Perth back in the day. But I think it might come back, and also these days
things are getting a lot more affordable and quicker with AI.
So basically, we’ve discussed saliva a lot over the course of our podcast, as you know, and saliva protects
the teeth by neutralising acid, washing away bacteria and delivering minerals like calcium and phosphate,
which helps to repair early enamel damage and make your teeth strong again and make cavities go away.
And when the quantity or the quality is reduced, the risk of cavities, erosion, gum disease and infections
increases a lot. And we’ve spoken a lot about this. Dry mouth and sensitivity, a lot of it comes down to saliva
and testing saliva.
So one of the tests that we would do would be salivary flow rate. I know this is going to sound a bit gross,
but it came with a little disposable cup and then a little piece of wax that you chewed on like chewing gum,
and you’d chew, chew, chew, and then you would spit into the cup, and we would time you for a minute. And
then we would see how much spit you were able to make. That’s called stimulated saliva. That’s something
that happens when you’re chewing.
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And then once we had that saliva, we could test it with a little dipstick and test the acidity, the buffering, how
quickly it was able to neutralise acid. And now even you can test if there’s bacteria or what kind of bacteria
are in there. And funnily enough, there must be a test for this P. gingivalis. It’s one of those ones we
discussed when we spoke about heart disease and Alzheimer’s, and there are now tests for testing these
things in the saliva.
As I said, we don’t currently do this, but maybe now after this podcast, I’ll be forced to do some of these
because we might create a bit of a demand. But back to the spit. So you spit in a little cup and you run all
kinds of tests. That’s called stimulated saliva.
And then we also would test, that’s something that we do sometimes when I’m doing an examination, we’ll
turn the patient’s lower lip inside out. You peel your lower lip down and it looks a bit like tissue paper if your
mouth is dry, but within a few seconds, you should start seeing little dew drops appearing on the surface.
And this is non-stimulated or resting saliva. These are the little salivary glands that are spread out
throughout your mouth that keep your mouth dry. We take them for granted until they’re not working.
So the stimulated saliva comes from big salivary glands, your parotid glands and the ones under your
tongue, your sublinguals, and these are like when you taste a bit of lemon and you feel your cheeks kind of
pucker. That’s all the saliva squirting out, or if you smell food or you ring a bell, if you’re a dog like Pavlov’s
dog, then you start salivating. I don’t know if you know the story of Pavlov’s dog? You ring a bell and then
the dog starts salivating because it associates it with food. Have you ever heard of that?
It sounds familiar, yeah. People say Pavlov’s dog to talk about these behavioural things where you learn to
respond in a certain way, or your body responds and it becomes subconscious, like when you smell food
and you say, oh, my mouth is watering. Your mouth literally does start watering.
But when we assess all of these things, then it changes dentistry from a reactive model to a preventive one.
And instead of waiting for decay or gum disease to appear, we could do all of these tests. But to be honest
now, when I examine patients, I can look at a patient and say, oh, you drink a lot of water because their
mouth is pooling up with saliva while I’m trying to look in their mouth, and we need suction while we’re just
trying to look. And that’s good saliva flow rate.
But I mentioned in some of the podcasts about saliva before, in South Africa and even in Australia, we’re
somewhat dehydrated. We don’t drink as much water as, say, Americans. And so I don’t need to do a whole
test to tell you you’re not drinking enough water, or are you on medication that’s causing your mouth to be
dry, and is it going to change the outcome? Probably not.
So do you want to pay another two or three thousand for a saliva test at this point? I’m not sure. I’ll look into
it and see if maybe the prices have come down or maybe it’s much quicker.
That was a very long answer. I think we’re done with today’s podcast.
[Eon Engelbrecht – E-Radio-SA] (7:11 – 7:25)
No wait, I still have nine questions for you. But I also want to ask you, talking about testing, can a DNA test
tell us if we are genetically more prone to gum disease and if so, how?
[Dr Clifford Yudelman – OptiSmile] (7:26 – 9:12)
So not everyone responds to plaque the same way. Some people get severe gum disease with relatively
small amounts of plaque while other people are more stable.
So there is a DNA test that can identify genetic variation and something that affects your inflammatory
response. And there is a gene, the one that’s been studied, it’s called IL-1. It’s a particular gene that when
people have that, I think it’s called interleukin-1, and it shows that you actually have an exaggerated
inflammatory reaction to bacterial challenge.
The genetics loads the gun, but the behaviour, like not flossing, pulls the trigger. And knowing someone’s
genetic risk can allow a dentist to personalise prevention strategies. And patients that have this kind of
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unusually bad gum disease, that are not smokers and don’t have diabetes, don’t vape, and there might be a
genetic factor and their parents lost their teeth from gum disease, I send them to the periodontist.
And I actually haven’t asked my periodontist if he does the genetic testing, but these tests are available. And
like I said, there are some practices going kind of very new age that do these, which is the reason why I’ve
done this podcast today.
In the end, you still have to floss. You’ve still got to go get your teeth cleaned every three months. You might
need to use antibacterials. There might be extra things you do, but it’s like knowing you’ve got heart disease
in the family. Like if you’re a family member, if you never had a heart attack in the family, does that mean
you should go and smoke?
No, I don’t think so.
[Eon Engelbrecht – E-Radio-SA] (9:12 – 9:19)
Dr Yudelman, can saliva testing identify the specific bacteria causing bad breath?
[Dr Clifford Yudelman – OptiSmile] (9:19 – 9:35)
Yes, again, I was very involved in the 90s actually with bad breath research and testing of bacteria, and we
had these machines called the Halimeter. This goes back to our very first podcast for Valentine’s Day two
years ago. When was that, 2024?
[Eon Engelbrecht – E-Radio-SA] (9:36 – 9:37)
Yeah, I remember.
[Dr Clifford Yudelman – OptiSmile] (9:37 – 10:58)
It was how to get a kiss on Valentine’s by not having bad breath. There are ways to test saliva and the
plaque and see if you have those bacteria. They’re called anaerobic bacteria on the tongue or in the
pockets, and identifying these bacteria supposedly allows targeted treatment rather than guesswork,
including special oral hygiene strategies and cleaning and maybe even some antibacterial therapies.
And some of these things, yes, while they can be done, the bottom line is you still need to floss, make sure
your gums don’t bleed and scrape your tongue, and maybe use a specialised chlorhexidine mouthwash or
toothpaste that will sometimes prescribe one of those non-staining ones called Curaden or Curasept.
We don’t like people using over-the-counter Corsodyl. It can cause staining on your teeth, which you can
polish off, but we have discussed those before. But do I really need to test and see exactly which bacteria it
is? For me, not really. But that’s not to say that we won’t test it in a year’s time or two years’ time, or that a
dentist or a practice that’s doing a lot of this is doing the wrong thing. It’s just not for me at this point.
[Eon Engelbrecht – E-Radio-SA] (10:58 – 11:07)
I also want to ask you, what is the IL-1 genetic marker and how does it affect your implant risk?
[Dr Clifford Yudelman – OptiSmile] (11:08 – 12:00)
Yeah, so again, that’s this interleukin-1, and it basically tells how aggressively your immune system will
respond to bacteria. And when it comes to dental implants, people who have this genetic, this bad gene, we
can actually maybe tell ahead of time that they could be more prone to inflammation and bone loss around
implants.
A lot of the time these days, instead of sending a patient to an oral surgeon to get an implant placed, or
placing implants ourselves, if it’s a patient that’s had a history of gum problems and so on, we’d send them
to a periodontist, and they may do this genetic testing and also personalise the treatment for that particular
patient. Maybe bring them in every two months instead of every three months for a professional cleaning.
[Eon Engelbrecht – E-Radio-SA] (12:00 – 12:07)
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Okay, and doctor, how do we test for the acidity or buffering capacity of saliva?
[Dr Clifford Yudelman – OptiSmile] (12:08 – 13:48)
I mentioned we collect the unstimulated saliva, which is where you just sit, you don’t chew on a piece of
wax, and then you wait a minute and then you spit. And then you do the one where you chew, chew, chew
and spit into a little cup, and you can analyse that.
And usually, if you’ve got low buffering capacity, it means that the saliva is struggling to neutralise the acids,
and that’s where we see increased risk of erosion and cavities. By the time we see patients, we already see
that they’ve got a dry mouth. They usually have a highly acidic diet, they’ve got gastric reflux, and there are
other factors to control. And yeah, it can help to say, we tested your saliva and you’ve got bad saliva. It kind
of gets them off the hook a bit.
They can go out and chew Juicy Fruit and eat those, what do you call them, Starbursts and sour lollies, drink
their apple cider vinegar and their hot water and lemon. But if you’ve got a good buffering capacity, does it
mean you should go and do those things anyway because your saliva is really great? I don’t think so.
So look, if you test people early on, maybe teenagers, and you can motivate people to drink more water,
motivate them to floss because they are at more risk, change and improve their diet, get them to maybe
chew sugar-free gum, increase, you know, some of these things we’ve spoken about in terms of how to fix
dry mouth.
The more your saliva flow rate is and the better the quality of the saliva, the better the buffering will be.
[Eon Engelbrecht – E-Radio-SA] (13:48 – 13:56)
And can saliva testing also help us to choose the right antibiotic for an infection, for example?
[Dr Clifford Yudelman – OptiSmile] (13:57 – 14:36)
So this is something that periodontists do. They actually can send for a culture of the, not necessarily the
saliva, but specifically crevicular fluid, or it’s like saliva but it comes out of your gum pockets. And you can
put a little, like a tiny white, almost like a piece of blotting paper, in the pocket and then sample that and then
send it for testing.
And this can actually help specialists pick antibiotics in very specific cases, and make sure that if we’re
going to give someone an antibiotic for their particular infection, that it’s the right one.
[Eon Engelbrecht – E-Radio-SA] (14:37 – 14:47)
I know this is probably a burning question for many. Is this testing expensive and is it worth it for the average
patient, doctor?
[Dr Clifford Yudelman – OptiSmile] (14:47 – 14:51)
I think everything’s expensive these days if you’re paying in rands, don’t you reckon?
[Eon Engelbrecht – E-Radio-SA] (14:51 – 14:54)
Yes, absolutely.
[Dr Clifford Yudelman – OptiSmile] (14:54 – 16:36)
So maybe in the US or a Scandinavian country, or somewhere where they’ve got good dental cover, I don’t
know if that’s anywhere in the world, but if there is a particular situation where the government or insurance
is going to pay, say, give me $300 to run these tests and it was free for the patient and those kits were
readily available, is it not, it’s like taking an x-ray. It’s always good to have the extra information.
But these things are expensive. DNA testing is expensive. But in particular cases like the ones that we
already mentioned, without repeating it, if it’s used selectively, then the cost could outweigh the savings.
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Like maybe doing the interleukin-1 test on certain patients or testing the bacteria in a particular pocket in
those very specific cases. Then targeted testing, I think, could be good.
And it’s also the way of the future. We have more of these types of things coming on board, and like the
rapid, it used to be a whole big deal to get a COVID test. Now you can just get it in the chemist and test
yourself for COVID, or like prick your finger and check your, more common, you might have something that
you just have a little spit in the morning and it will tell you if you’ve got bad breath, tell you your gums are
bleeding. I think these things will come online and get much cheaper, and it could just be an everyday thing.
[Eon Engelbrecht – E-Radio-SA] (16:36 – 16:43)
That would be great. Also, doctor, how does this all fit into personalised medicine in dentistry?
[Dr Clifford Yudelman – OptiSmile] (16:44 – 17:46)
If you do all these tests and you’ve got a patient sitting in front of you, and they’re a new patient and you
don’t know them, it could be a way to motivate them to come in every three months instead of once a year.
There are a lot of other factors that will come into play.
But it’s just like when we run an x-ray through the AI and the AI finds three cavities, then it’s not just the
dentist saying that. And it’s the same with a test. People love wearing, even myself, you wake up and you
feel fresh. I didn’t hit you in the ribs because you were snoring. Do you need something on your wrist to tell
you that you had a good night? It’s like, do you really need these things or are they just fun to have?
But I do think it will become more widespread, and obviously everything’s going that way. Now AI is making
a lot of these developments much quicker and better.
[Eon Engelbrecht – E-Radio-SA] (17:46 – 17:54)
So saliva testing can really pick up a lot, but can it detect diseases like diabetes or even cancer?
[Dr Clifford Yudelman – OptiSmile] (17:55 – 19:17)
Yeah, so look, there’s a lot of research on that. So it’s not something that’s routine, but they are working on a
lot of that. I think it would be much, I read something actually about a little sensor that they’re working on
that you can attach to your tooth.
So instead of these expensive sensors that you pop, it’s like a tiny needle that goes in your arm, and if
you’re diabetic or you’re doing a keto diet, it sends a signal by Bluetooth to your phone and you measure
your blood sugar every five minutes. And if it’s something that you could just bond on the tooth and it gives
you your instant blood sugar readings every five minutes from your saliva, that would really be something.
And I know that they’re working on that.
And the same thing, there are things where I think you’ll be able to detect certain cancer-type things. Your
saliva is, as I said, very similar to your blood. There are a lot of things in your saliva that could tell you what’s
going on in the rest of the body. But as far as I know, without doing a deep dive and seeing what’s coming
down the road, because most of our podcasts are about what’s going to happen tomorrow when you go to
the dentist or questions to ask the dentist, so this is a little bit more future-looking.
[Eon Engelbrecht – E-Radio-SA] (19:18 – 19:25)
And then just finally, for those wondering, how do you perform the test? Is it just spitting in a tube or not?
[Dr Clifford Yudelman – OptiSmile] (19:25 – 19:59)
So I think that’s where I jumped the gun earlier. Basically, it’s a little piece of wax that you chew on, and then
you spit into a little cup, little measuring cups. Obviously, there are no needles.
For DNA testing, you can get a kit in the mail that you either use saliva or you just scrape the inside of your
cheek, and you get all that DNA. All of that information is all basically floating around in your mouth. But
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yeah, it’s non-invasive. You don’t have to prick your finger or do anything. It’s just you spit in a little cup. And
that’s it.
[Eon Engelbrecht – E-Radio-SA] (19:59 – 20:15)
Okay, okay, okay. Well, that was a very fascinating look at how modern dentistry is moving beyond simply
fixing your problems and towards understanding your risk earlier. Dr Yudelman, thank you so much as
always.
[Dr Clifford Yudelman – OptiSmile] (20:16 – 20:34)
Pleasure. And yeah, looking forward to next week. Things should hot up a bit where we talk about biological
or biologic versus evidence-based dentistry. I’m sure to make a few enemies in the dental world next week.
[Eon Engelbrecht – E-Radio-SA] (20:35 – 20:36)
Okay, well, looking forward to that.
[Dr Clifford Yudelman – OptiSmile] (20:37 – 20:39)
Tune in, tune in or tune out.
[Eon Engelbrecht – E-Radio-SA] (20:39 – 20:54)
That’s quite a teaser there. Okay, so do join us again next time on Save Your Money, Save Your Teeth,
where we continue helping you make smarter decisions for your smile, your health and also your wallet.
[Outro] (21:15 – 22:00)
Discover the world of dental excellence with OptiSmile. Join us for a weekly podcast featuring Dr Clifford
Yudelman, a seasoned expert with 40 years of dental experience across four continents. Gain unique
insights and expert dental advice by visiting OptiSmile.co.za for articles that illuminate the path to optimal
oral health.
If you’re seeking unparalleled dental care in Cape Town, get in touch with OptiSmile or book directly online
on OptiSmile.co.za.
OptiSmile, where global expertise meets local care.
Disclaimer: The content provided in this podcast, “Save Your Money Save Your Teeth” on Medical Mondays, is for informational and educational purposes only. It is not intended to serve as dental or medical advice. The insights and opinions expressed by Dr. Clifford Yudelman and any guests are designed to foster a better understanding of dental health, preventive measures, and general well-being, but should not be interpreted as professional dental or medical recommendations.Dr. Clifford Yudelman does not diagnose, treat, or offer prevention strategies for any health conditions directly through this podcast. This platform is not a substitute for the personalized care and advice provided by a licensed dental or healthcare professional. We strongly encourage our listeners to consult with their own dental care providers to address individual dental health needs and concerns.The information shared here aims to empower listeners with knowledge about dental health but must not be used as a basis for making health-related decisions without professional guidance. Your dental care provider is the best source of advice about your dental and overall health. Please always seek the advice of your dentist or other qualified health professionals regarding any questions or concerns about your dental health.
