Episode highlights:

• The oral microbiome is an ecosystem: Bacterial balance matters more than simply eliminating bacteria.
• Inflammation changes the conversation: Oral dysbiosis may influence immune responses throughout the body.
• Mechanical biofilm removal matters: Reducing bacterial and inflammatory stimuli is an important part of maintaining oral health.
• Personalized care is essential: Caries risk, periodontal status, lifestyle, and individual patient needs should guide oral hygiene recommendations.
• Look beyond active ingredients: Toothpaste ingredients such as sodium lauryl sulfate (SLS) may contribute to irritation and sensitivity in some patients.

Episode description:

What if achieving better oral health isn't about eliminating bacteria, but creating the right balance? In this episode of A Tale of Two Hygienists, Camille Zenobia, PhD, joins Jessica Atkinson and Dave Torres for a fascinating conversation about the oral microbiome, inflammation, and the connection between oral health and the body's immune response. Drawing on her background in microbiology, academic research, and the dental industry, Camille explains how a dysbiotic oral microbiome can influence inflammation and why understanding the relationship between bacteria and the immune system is essential to improving patient outcomes.

The conversation explores the importance of mechanical biofilm removal, the role of inflammation in periodontal disease, and why personalized oral hygiene recommendations matter. From evaluating toothpaste ingredients like SLS to considering individual caries and periodontal risk, Camille challenges dental professionals to move beyond one-size-fits-all recommendations. With practical insights, memorable analogies, and a fresh perspective on the mouth as an ecosystem, this episode encourages dental hygienists to approach patient care with greater curiosity, intention, and confidence.

A Tale of Two Hygienists podcast: Episode 563

Why the oral microbiome matters — 01:06

Dave Torres: Welcome back, listeners, to another episode of A Tale of Two Hygienists. I am your co-host, Dave, and I'm here with my amazing co-star, Ms. Jessica Atkinson.

Jessica Atkinson: Hello, everyone! We are happy to be here with you. We have a lovely, lovely human being on the podcast today, and I'm really excited for our conversation because this is something that impacts my life. Right now, here in the U.S., we are a little afraid of lettuce right now, right? We're recording in July at RDH Under One Roof. Thank you for coming, Camille, and being here in person. We're so happy to have you here. This episode is going to be airing in November, so hopefully we're not as scared of lettuce by then. God forbid, right?

We're going to be talking about the oral microbiome. So, Camille, tell us a little bit about yourself and why the oral microbiome is so important to you.

Camille Zenobia: Oh, that's a really good question. I actually started my career as a hairdresser.

Jessica Atkinson: Did you? Oh my gosh, I love this!

Camille Zenobia: Yes, but I quickly got bored and had to go back to school. I was so involved with science. I wanted to research. I wanted to dig into all the things. But mainly, my biggest question was, why in the world can we all be exposed to the same thing, like with COVID, and some of us are asymptomatic, spreading a little bit of dose here and there, while the rest of us are on ventilators and dying?

Jessica Atkinson: Right.

Camille Zenobia: Like, why?

Jessica Atkinson: Or lettuce.

Camille Zenobia: Right. Or lettuce. And so that is what drove me to go get a PhD in microbiology. I was studying infectious disease. I landed all of my entertainment value in the oral host microbiome ecological setting, and I really fell in love. Why? Because we really don't understand very well the immunological background of how we communicate with the oral microbiome in real time. As we discover the depth of that relationship, we're starting to understand why some people get sick and others don't.

So, I'm really excited to be here at Under One Roof because a lot of the research is pointing to the oral cavity as the reason why.

Jessica Atkinson: We have a lot to talk about. So you're coming at this with a PhD in microbiology.

Camille Zenobia: Yes.

Jessica Atkinson: And then tell me how that translated into being here at RDH Under One Roof.

Camille Zenobia: Thank you for asking that. I started my PhD with Richard Darveau at the University of Washington. He was dean—well, he wasn't at the time, but he became dean of periodontology at that school, and he was an amazing mentor. He was basically looking at the endotoxin of the oral cavity and understanding how it can flexibly react to inflammation.

Jessica Atkinson: I'm going to need a little bit more there. We're going to unpack that a little bit.

Camille Zenobia: So, the endotoxin—well, we're not going to unpack that yet. We'll come back to that. Then I went to the University of Pennsylvania with George Hajishengallis, who's an amazing periodontologist there. He is a hard academic in inflammation and memory response in the oral cavity. During my academic career, I also collaborated with the Forsyth Institute very heavily with the Van Dyke laboratory. So I've touched a lot of amazing academics in this space. We have learned so much that I don't think is deployed or communicated adequately. That's why I'm here.

Jessica Atkinson: Yeah, I mean, I've been a dental hygienist for many a year. I don't know if I want to disclose many a year, right?

Camille Zenobia: We could just say 100 years.

Jessica Atkinson: One hundred years. I have been a dental hygienist for 100 years. I'm also a dental hygiene educator. Often, students will say about courses like microbiology or embryology that sometimes it's hard for them to make the correlation to clinical work.

Dave Torres: Different language. I remember taking the subject, and I'll tell you, my only knowledge of this is just the courses that I took as a prerequisite, right? But it's a whole different language that you're learning and understanding. I'll be blunt: understanding how that relates to what we see is a challenge. I know you can get a sample of plaque, put it under the microscope, and understand the bacteria that way. It's almost as though you have to see it to believe it. But I'm actually very curious and fascinated about what upcoming things are happening that we haven't yet relayed.

So, if you were to put this conversation under a microscope, what are some of the things that I'm missing?

Inflammation, dysbiosis, and the bacterial balance — 06:43

Camille Zenobia: One of the things that I think is key—and, by the way, I went from academia into Colgate because they wanted to create new stories for their old technology. I couldn't put that in a podcast.

But to connect these dots, exactly: How are our formulations behaving in this new understanding of oral hygiene?

Jessica Atkinson: And are they doing what we want them to actually do?

Camille Zenobia: Exactly.

Jessica Atkinson: That's fascinating. Yes.

Camille Zenobia: So this is why I'm here. What I think is missing is the importance of the inflammation backdrop.

Who started it doesn't matter. At the end of the day, you have an ecological system that is under duress. You have a microbiome that's dysbiotic, and you have an inflammatory backdrop. All of these things are communicating with each other.

What is happening at that level is that inflammation is a signal for the bacteria. The bacteria that we don't want to be there, or that we think we don't want to be—our red complex. Porphyromonas gingivalis is like your keystone.

Jessica Atkinson: “Get out of there!”

Camille Zenobia: Yeah, exactly. We want him to die. But if I talk to you about what he's actually doing in there, you're going to be like, "Do we want him dead? I don't know. I'm a little confused now." Why? Because what he's doing is taking the inflammation and eating it. So, do I want him dead?

I think we want him in low abundance because when he's starving, he's a good team player. But when he's a fat boy, then he's not a good team player. I think that's the difference.

We need to think about this in a whole different light. We don't want to get rid of everybody. We want them to behave in a social setting that is coordinated.

Jessica Atkinson: I am curious: If I had a patient in my chair with Stage 2, Grade B periodontitis, right? We have an active infection happening. How do I help them understand this process in a way that is actionable, outside of my regular offering?

Or how can I change the way I educate my patient on what I am doing with my nonsurgical periodontal therapy in a way that might be hitting them more on a microbiome level than just saying, "I'm going to do this physical removal of plaque and calculus"?

Camille Zenobia: So, this is actually what I kind of tailored my talk around this time. We really need to talk about the mouth as how we surveil our environment. It is where we start our immune programming.

Jessica Atkinson: So I'm thinking about a baby.

Camille Zenobia: Yeah.

Jessica Atkinson: I'm thinking about the very first steps of development.

Camille Zenobia: Yeah.

Jessica Atkinson: And when they pick things up, they automatically explore. And how do they explore? Where do they put it? Everything. They put everything in their mouths.

Dave Torres: “Why would you do that? Don't do that!” Right? But they're babies. They're exploring. Or even parents, right? How many times have I seen parents with pacifiers? The baby drops them on the floor, and then we're just sucking on them to clear away the dirt to give them back to the baby, right?

Camille Zenobia: So it's these—

Jessica Atkinson: Foundation blocks of creating a... Tell me more about that.

Camille Zenobia: Yeah, okay. So, in a healthy setting, especially in a baby, we're training tolerance. We're inviting our environment to play nicely with us. We're tasting everything. We're putting it in our mouths. We're training tolerance. We're going to be tolerant to the things that we see every day. We're going to be suspicious of things that we don't see all the time.

This is the action of the baby. This is the action of a person in real life, putting things in their mouth and training our immune system accordingly.

So, things that I eat every day—I'm going to eat a peanut butter and jelly sandwich, maybe. Am I going to get a peanut allergy? No, because I'm a healthy human being, and I'm just going to expose myself all the time, and I'm going to be fine.

And when you're not training on a healthy— When we create a vaccine, we need three things. We need an adjuvant. That's a thing that stimulates the immune system to create a danger signal: “This is harmful.” “This is unique.” “This is something we don't see every day.” “Kill it, kill it.”

And so we're going to train our immune system to kill it.

In healthy systems, we don't have any inflammation. An adjuvant is the thing that sends that signal that this is something new, this is something alarming. Then our antigen is the thing we want to remember, like COVID. We want to remember that we saw that so that we don't ever have to deal with the consequences again. Our immune system is going to be like, "Oh, that guy. That guy. Yeah, I got this. I remember those."

Then we need a delivery system to make sure that we can retain the memory. The dose and the duration of dose response—we need that to endure for a minute for our immune system to be tailored appropriately.

In the mouth, when you're tasting things every day under an inflammatory setting, you're training not tolerance; you're training sensitivity. You're training immune response. So, when you have periodontal disease and you're exposed to COVID, you have an overresponse because you're already turned on. You already have an adjuvant, and that is your new oral microbiome that's dysbiotic. It's now training your immune system differently. This is what I think is the takeaway.

There are plenty of studies. There's a really cute one out of Japan that showed elderly patients just going to the same care facility for their elderly patient treatment. They split 190 patients into two groups. One group got professional hygiene, oral hygiene, and the other group just went for their normal visit.

At the end of flu season, they evaluated how many got sick in the control group versus those who had hygiene protocols. The people who had professional hygiene intervention: 1% of the population were infected. 9% in the control group.

Jessica Atkinson: I mean, and that's a jump. For those who aren't as familiar with how statistically relevant studies are, that's something to take note of. That's incredible.

Camille Zenobia: Yeah. And so that's what I'm trying to get everybody to understand: The mouth is an immune training ground. When we're training on inflammation, we're training a whole different language for our body to respond to.

I could go into an hour-long dictation of how exactly this is happening at the cellular level, which microbes are involved, and all the immune cells. But at the end of the day, it doesn't really matter. What matters is that the training ground is the wrong ground. How do we get back to health?

So, you mentioned periodontal disease. Once you're in periodontal disease status, you have fundamentally changed your immune system to permanently be turned on. You're now just always at risk.

Jessica Atkinson: So you're hypersensitive.

Camille Zenobia: Yes. So now you've crossed the line. If we catch you in gingivitis land and we do a damn good job of reversing—

Jessica Atkinson: And let's emphasize that: the ground where we can reverse. That's where we need to really double down. Which is why I love—lots of people are calling it the new periodontal classifications, but they're not that new, guys. Some people say it's too aggressive. It's too—you're saying that's not that big of a deal. And I'm like, no.

Camille Zenobia: It's a huge deal. Let's talk about what we found. COVID was such a great training ground for all of us. We got so much data out of that moment, and we're still learning from it. In periodontal disease, we knew—we saw it coming in real time. People with cardiovascular risk were dying.

Jessica Atkinson: Yeah.

Camille Zenobia: Fast.

Jessica Atkinson: Yeah.

Camille Zenobia: And periodontal disease was also a risk factor that was just as horrid.

Jessica Atkinson: Yeah.

Camille Zenobia: So if you had periodontal disease, you were overresponding. You had higher ICU admission, higher ventilation requirements, and higher mortality because your immune response is fundamentally shifted under that immune training system.

Why personalized hygiene care matters — 17:19

Jessica Atkinson: This is inspiring me to double down on how much I love double IG.

Camille Zenobia: I don't like double down on me. Like, no, I'm serious. We are integral. We are essential. We are that prevention piece in this training ground of our immune system.

And I don't say it glibly—we are saving lives when we take it seriously.

Camille Zenobia: Yes. And so I'm so excited to be here. I love hearing from the greatest. Kami Haas is a good friend, and I love what he does. He does an amazing job.

But he so perfectly captured the problem in that, you know, if I go into my doctor and I say, "Oh, I have a cold," and he says, "Here's your one-size-fits-all treatment for everything: Tylenol. Here you go."

Then I come back and I'm like, "I feel nauseous. I'm pregnant." And he's like, "Here's your Tylenol." Then later I have cardiovascular disease, and he's like, "Here's your Tylenol."

That’s what we're doing with fluoride. We don't think about personalization in the hygiene world. This is something that I think is a disservice.

I told you I came from academia. I told you I also worked in industry, in manufacturing toothpaste.

Jessica Atkinson: And you're also a patient.

Camille Zenobia: And I'm also a patient, yes. I could go on for days about all of those three things, but I would say that the takeaway is that our formulations have not caught up to the science that we understand today. We have to take a more personalized approach to understanding the mechanisms and what is happening in our patients. Are they a caries risk? Are they a gingivitis risk? What is happening with them at this moment? Is it pregnancy? Stress.

Jessica Atkinson: The social determinants of health, guys.

Camille Zenobia: Or are we having a moment where we're putting in some liners and we're now a caries risk? Gingivitis is not the main issue right now, today.

We need to be mindful. We need to catalog what they're using, talk about it, talk about the mechanism of action, understand them, and be able to confidently move forward in what we might want to change in those moments. Because not everybody has the same mouth.

Jessica Atkinson: No. From a microbiology standpoint, I mean, we can go into lots of chemistry, but something that is available to everyone is mechanical removal of biofilm.

Can you speak from a microbiology perspective on the efficacy of mechanical removal? I'm just talking about a dry toothbrush, guys, without adding any bells or whistles. I'm curious about that.

Mechanical biofilm removal and the importance of time — 20:11

Camille Zenobia: So one of the things—I'm just going to move back to the hygiene intervention. We have human models of disease. We can't induce perio. That's unethical.

Jessica Atkinson: Right.

Camille Zenobia: Bone loss? Are you crazy? Absolutely not. And, by the way, the bone loss in your mouth is just a mirror of the bone loss that's happening everywhere.

Dave Torres: And I just got a new wrinkle in my brain. I didn't even think about it that way.

Camille Zenobia: Exactly. Yeah, we could talk about that. But what you're doing in physical removal is you're removing the total input of adjuvant dose.

Jessica Atkinson: Okay, adjuvant dose.

Camille Zenobia: Right. I told you the adjuvant is the thing that irritates the immune system and makes you skew your memory. If you remove the dose aspect and you're now having a lower dose, you give your system time to recover and respond more appropriately.

Dave Torres: Tell me more about time, because we oftentimes hear about twice a day for two minutes, seeing the patient every six months. But I argue there's a lot of patients out there who should be doing it more frequently. Yes, they're seeing those more frequently, and that's not even counting the stress factors or medical histories and all that stuff.

So tell me more about time.

Camille Zenobia: It's important. We know that brushing at night is the most important brush cycle that we have in the day, so don't skip that one for sure.

But as far as how many times someone should get treated, I'm going to argue that we need to understand their risk value. So if they are high risk, if they are in periodontal disease land, they need to be seen more.

Dave Torres: Absolutely.

Camille Zenobia: Every three months, in my opinion. I know that's a fuzzy time period, but it is backed by data. I have confidential information from behind the scenes that would suggest that we are aware that people who are higher risk do better when they're in more often, and some dental insurance accommodates this. I just wish we could evaluate each patient accordingly, and it wasn't just a provider-specific element.

Jessica Atkinson: We are all about magic wands around here. So, if we have—we, in my universe that I would like to live in, right, with my magic wand, where we do not have these systems that are imposing upon, honestly, the best care of the patient, right? If you were to see someone more often, what I'm hearing is that when we do that, we are decreasing their risk of death.

Camille Zenobia: Yes. Okay, let's simplify this even further. You're going to make them more monetarily viable. They're not going to call in sick as often. They're going to feel better all of the time because they're healthier all of the time.

Dave Torres: It's the mindset of—I mean, I tell this to my patients: They can never be too clean, right?

Camille Zenobia: I mean, it's not. I want to walk back the clean idea because I think that—

Jessica Atkinson: Because our little P. gingivalis—when he's starving, we like him around. So we want a little bit of dirt.

Camille Zenobia: A little bit of dirt.

Well, it's not even that. Our mouth is a garden, and we should think about it like we're going to care for it because it can take care of itself when it's well balanced.

We just have to make sure that we're paying attention and responding accordingly. We're going to brush every day without question, with the right product of the day for our risk assessment. When we're thinking of our hygiene appointment, if I'm super healthy and I have no risk value at all, and I'm using a non-fluoride product—because who cares, I have low risk, and I have decided that my non-fluoride is going to be a little support here and there and nothing too aggressive—just like watering the garden.

I'm going to go in at least twice a year just to make sure that I get a touchpoint and an evaluation.

Jessica Atkinson: And data.

Camille Zenobia: Yeah. And that's more than what is suggested for my primary, a once-a-year blood test of all the things. I still want to see my primary more. I'm just going to be honest. I'm not a guy. So, you know, I want to know more.

Jessica Atkinson: I need some data.

Camille Zenobia: I want some data. I'm a girl. We haven't been without any data. Come on.

Jessica Atkinson: What I'm hearing is she is volunteering as tribute.

Dave Torres: But that's a good point. If a patient were to ask me, "Hey, can I come in every two months? Am I doing anything too frequently?"

Camille Zenobia: It depends. Are they an over-brusher? Are they aggressive? Are they maybe a hypochondriac? Let's talk about that. I do think there's room for that. If they want hand-holding and they can afford it, I think, you know, have that soft intervention. Maybe don't go aggressive each time.

But for those—which is more typical—where we have periodontal disease and we're still only coming in twice a year—

Jessica Atkinson: Or once.

Camille Zenobia: Right.

Jessica Atkinson: Or, I mean—

Camille Zenobia: Or every five years. Yeah. I mean, I understand that there are—

Jessica Atkinson: A lot of things at play, yes. Remember when we were talking about our favorite universe? In our fantasy land, which I think in some people's cases is achievable.

Camille Zenobia: I think when we're talking about concierge care as standard of care now, I know we can kind of entertain these values. I do love the options that we're now given where I can find a practice that I can just pay a monthly subscription to and go in as needed. I love that idea.

I think having more options is better. I think that gives us room to play. And the more I know as a consumer, the more I'm going to deploy these activities.

Helping patients build a healthier oral microbiome — 26:52

Jessica Atkinson: And this is what I want for the consumer to know: to help hygienists get autonomy, to help them get their garden in a state that is healthy and helps them fight off the storms of life.

As a consumer, by and large, not many of them know the education or the ability that a dental hygienist has to really turn the tides for them on all of these things that we've discussed.

They may be getting some other information about how to make their garden healthy. And so I'm curious, from your background, what are some things that you would like to share with our audience? What are some things to avoid or some things to start?

We talked about mechanical biofilm removal. That's something that's great, huge, everybody can do.

Camille Zenobia: Standard of care.

Jessica Atkinson: Standard of care. Are there some things—because in my mind, I'm like, well, maybe I need to get on a probiotic. Maybe I need to add something or not do something that I'm not aware of because I'm not as familiar with how to make the right bacteria starve and the right bacteria be chubby?

Camille Zenobia: I mean, there are a lot of cool new technologies.

Dr. Stein with smart technology, teeth technology has a supplement where she's basically doing that. She's starving out the bad bacteria and having good success. I'm waiting for some more clinicals, but she's doing a bang-up job. She's an incredible scientist. She's a PhD out of Minneapolis. That would be an adjunct therapy. So it's a lozenge, and I really like that option because you can add it to your already easy routine.

Jessica Atkinson: Yeah.

Camille Zenobia: You don't have to change your toothpaste. You just go about your day and add this other thing. I would say if you're still having problems on your current hygiene products, reevaluate for sure. Ask what is happening, and then look for a product to address it.

Jessica Atkinson: And for the professionals listening to this, how would it be to approach your patients and say, "Hey, with the data that we have from last time to this time, we're not seeing any change. Let's look at the ingredients and what you're using." That requires us to be what we are, which are dental hygiene professionals.

Camille Zenobia: Yes.

Dave Torres: Well, and also alleviating that stress of, like, "Did I miss anything? Am I not doing everything right?" Because oftentimes that's the first thing that pops into my head. I'm like, I'm seeing them at recare. I'm reevaluating, and I'm like, snapped. It's not getting any better, and now I'm puzzled.

Camille Zenobia: Right. Exactly. You've done your job. They've done their job, and something's still not moving the needle.

Dave Torres: Yeah, exactly. And it's frustrating. One thing I learned about this is being able to connect those dots. The beautiful analogy of the garden was, yeah, we've got to water, we've got to nurture it, we've got to keep an eye on it.

Camille Zenobia: Now we've got to weed.

Dave Torres: Yeah, exactly.

Going back, I do have some of these patients who are like, "Yeah, if I need to come here more frequently, money's no object. Because based on what you just said, if I'm healthy, I can take an hour out of my day, come over here, and I don't have to call out sick. I don't have to do all these things, and I don't have to have that in my head. Now I'm going to let you be the professional, and you know, you're my dental coach, right?”

But we also have those patients where we're like, man, we wish we could have come back sooner. I think those conversations are to be had where we're like, "Hey, let's dig deeper. Let's ask more questions."

So what are some of those questions that I could be asking?

Toothpaste ingredients, SLS, and gingival sensitivity — 30:47

Camille Zenobia: One of the studies that I recently looked at was 1,600 patients out of Norway who were evaluated because they had sensitivity to many different things. They had allergies to several things, they had several issues, they had hypersensitivities, and they were reactive in their gingival tissues.

42% of them were simply irritated by the SLS in their toothpaste formula.

Jessica Atkinson: Interesting.

Camille Zenobia: That's almost half. So if you were to ask them if they have a handful of allergies, if they have more than one allergy, maybe we should really look at these toothpaste formulas because the formula alone, not even the active, the formula is doing you—

Jessica Atkinson: The inactive ingredients are creating a dysbiosis and making our patients more sensitive to the things that they're experiencing.

Camille Zenobia: Exactly.

Further reading: The benefits of oral probiotics in periodontal treatment

Patient-centered care: What we put in and what we take out — 31:47

Jessica Atkinson: Okay, so I'm looking at my clock going, I need another half an hour with you. I need another lifetime with you. I have 400 more questions.

But my takeaways, Camille, here are: patient-centered care. Be curious about what you're putting in and be intentional about what you're taking out.

Thank you so much for being with us. I have so many more questions, but we will have you back.

Camille Zenobia: Excellent. Fantastic. So good to be here.

Jessica Atkinson: It is so good to have you.

For all of you listening, I'm so sorry, I'm going to continue this conversation offline. But if you need to get a hold of Camille, we will also include her information. Thank you, Camille, for being here with us.

Dave Torres: Yeah, write us an email and get back to us. This is a great conversation start, right? Being able to take these takeaways and put them into patient practice is what we are all trying to achieve. So thank you for your time.

Camille Zenobia: Thank you.