Brushing and Flossing Are Not the Best Ways to Avoid Cavities
Hopefully that title hooked you a little bit. Let me just state up front that as a dentist, I wholeheartedly advocate for daily, quality brushing and flossing. However, in the latter part of my career, I find I spend a lot less time talking about it with patients than I used to. Why? Because in sixteen years of practicing dentistry, I’ve realized that it’s simply not the biggest contributor to whether or not someone winds up with tooth decay. It’s important, but it’s not the most important. More on that later. But first, how did I come to this conclusion?
Well, I’ll be real honest.
I see people on a regular basis who don’t have ideal dental hygiene, yet they never have decay. And on the contrary, I frequently see people to whom, despite having excellent plaque control, I have to deliver the unfortunate news that they have yet another cavity. Years ago this made me rethink the conservations I had with patients around cavity prevention. Was it enough to just tell them to brush and floss more? Was the teenager that made a piss poor effort at brushing going to step up his game if every time he came in, there didn’t seem to be a consequence for his lack of brushing (i.e. no cavities)? Unlikely. Or on the flip side, how did it make the patient who had a new cavity every time she came in feel when someone told her to “brush and floss more,” when she knew she was already doing that diligently every day? My intuition told me that week after week, when I had finished surgically restoring an entire mouth of cavities on a four or five year old, that simply telling the mother that she should make sure the child “brushed and flossed better” wasn’t really going to move the needle.
It occurred to me that if I were brushing and flossing religiously every day only to be told every 6-12 months that I had another cavity, and all my dentist said to me was, “You should really focus on your brushing and flossing,” I think I’d be trying to find a new dentist.
Making this observation in my career made me curious. I had anecdotally decided that there was more to cavity prevention than good hygiene, but my intuition was based largely on the clinical observations of my patients. As fate would have it, when I later became dental school faculty, one of the courses I was assigned to teach was Cariology, which in simple terms means the study of tooth decay. Teaching this course provided me with a formal and academic platform that facilitated a deep dive into the current understanding of why people get cavities and what we as dental professionals can do to prevent it.
And I learned that my intuition around my clinical observations was right.
Being right doesn’t mean much, though, unless you do something meaningful with it. I decided that I was going to reshape my conversations with patients. And in order to do that I had to make a decision about how I was going to approach those conversations. In general, I think all of us as health providers have two major choices to make about how we fundamentally approach our practice, and they are the following:
Am I a root-cause treating provider or am I a symptom-treating provider? (We all do both, but inevitably as a health professional you will commit to one or the other as the foundation of your practice).
Do I trust that my patients can handle the truth and make decisions for themselves or will I make those choices for them?
Let me be clear that the health education system is largely set up to train health care professionals to be symptom-treating providers who do not trust that their patients can make good decisions for themselves. In Dr. Casey Means’s book Good Energy, she recounts the frequent times in her medical training that she was told that “patients are lazy and that they will inevitably eat bad food and make bad decisions.” She goes on to say that this “pessimistic view of patients is endemic in medicine.” In my experience, while no one ever overtly told me my patients would be lazy, no one ever gave me an alternative to drilling, filling, and fluoride either. It seemed that it was just assumed that patients would get cavities, and drilling, filling, and fluoride were the tools we had available to us as a dental profession.
The overwhelming majority of people who enter healthcare as a profession do so because they want to help people be well. But unfortunately, they often do not receive the tools in their training to identify or treat the root causes of disease. Instead they are trained to use prescription pads and surgical instruments, which are useful and necessary. But. They should not be the only tools in the toolbox. Nor should they be the first.
Once I went down the rabbit hole of what causes oral disease (tooth decay, gum disease, infections, etc.), there was no returning to a symptom-treating approach for me. Because once you know, you can’t unknow. And I knew I could no longer tell my patients to just “brush and floss” and be okay with that. So, I pivoted. And those commitments to both treating the root causes of disease and trusting that my patients have the capacity to make informed choices for themselves are the foundations of my practice today.
So let’s loop that back to cavity prevention. Why do people get cavities? Let’s break it down.
All tooth decay is caused by a pH problem in the mouth, i.e. too much acid. A low pH (too much acid) causes breakdown of tooth structure. Hopefully you’re asking why one might have a low pH in their mouth. Yes? Good, glad you asked.
Answer: An imbalance of good and bad bacteria (dysbiosis of the oral microbiome) is the number one reason why someone has too much acid in their mouth. Why does dysbiosis cause low pH/too much acid?
Answer: Because the bad bacteria that overpopulate the mouth not only produce acid, but they thrive in acidic conditions, outcompeting any good guys who would otherwise promote a healthy oral environment. So, what causes these bad bacteria to take over?
Three main things:
Feeding the bad bacteria their preferred foods that result in cranking out high volumes of acid (sugar, crackers, chips, cereal, bars, pretzels, etc.).
Anything that dries out the mouth and depletes saliva, which is your body’s main defense against the acid (mouth-breathing, medications that cause dry mouth, etc.)
Not removing the plaque (the sticky white film where bacteria accumulate) from the surfaces of the teeth where acid is then allowed to pool and break down the enamel of teeth (lack of quality brushing and flossing).
So why then, do some people who don’t have a lot of plaque still have cavities?
A: TOO MUCH ACID.
And why do some people, who have more plaque than would be considered ideal, not get cavities?
A: THEY DON’T HAVE AN ACID PROBLEM.
In short, not all plaque is created equal. Whether or not you get tooth decay is dependent on the quality of your oral microbiome.
Now for funsies, let’s just talk about the standard American diet and how much we’re feeding those acid-producing bacteria exactly what they need to cause destruction on a regular basis, knowing that 70% of the average American diet is comprised of ultra-processed food.
Candy, soda, cookies yes. But also: Gatorade, sweet tea, chocolate milk, lemonade, Capri Suns, Goldfish crackers, any crackers, chips, pretzels, puffs, cereals, granola bars, frappucinos, sugary energy drinks, and on and on.
Double whammy if what you’re eating/drinking is also acidic all on its own: energy drinks (sugared or non-sugared), soda (diet or regular), sour candies (I’m looking at you Sour Patch Kids—the trifecta of a cavity bomb-sweet, sour, and sticky), Gatorade, orange juice, lemonade, etc.
You get the idea.
And now, know that every time you take a bite or a sip of any of these high-risk foods or drinks, your teeth are under acid attack for 20-30 minutes. If you take another bite or sip, start that 20-30 minute clock over. It now starts to become pretty apparent why when many Americans consume a diet full of high-risk foods and drinks all day long, that simply advising them to “brush and floss more” isn’t really an honest approach to change.
For all the reasons above, the number one preventive measure that I now take when discussing cavity prevention with my patients is taking a little extra time to find out what a person’s diet looks like and discuss potential causes of dry mouth. Of course we still talk about brushing and flossing. But if someone walks out of my office thinking they can eat cereal for breakfast, sip on a sugared coffee over 3 hours at their desk, have chips with their lunch, snag a couple of Fun Size Kit Kats at 3:00 in the break room, pick up fast food for dinner, and then wind down with Netflix and some Triscuits before bed, but avoid cavities as long as they brush their teeth, I have failed as their dentist.
You can’t out-brush a high-risk diet. Period.
Which leads me back to my second commitment as a health care provider: trusting patients to make decisions for themselves. Doctors are not gods. We don’t know everything. We are given almost blind trust by our patients (or at least that used to be the case…that tide is changing). It is our job to use our knowledge, training, and compassion to help guide our patients toward health. To do that, we have to educate and empower patients to make decisions in their own lives. I can’t follow my patients to the grocery store. I can’t brush their teeth for them at home. And I can’t ultimately force them to care about what I think they should care about. Nor should I. But I am not pessimistic about my patients’ desires or abilities to change their own lives, because once I committed to this approach, I saw them do it over and over again.
I had to facilitate, not dictate.
So yes, let’s all brush and floss like champs. But let’s also eat healthier. Sleep better. Move more. And treat each other like we deserve to be healthy. Because we do.