Is Tooth Cleaning a Scam?

One of my earliest and happiest memories was being released from a hospital oxygen tent when I was a small child. I had developed pneumonia and was in pretty bad shape. They not only kept me under an oxygen tent for several days at St. Luke’s Hospital in Kansas City, but they also gave me massive amounts of tetracycline.

The good news is that I recovered. The bad news is that from then on, my teeth have had pretty severe tetracycline staining. This is not just surface discoloration — my enamel through and through is grayer than I’d like. I tell you this because I’ve always had an uncomfortable relationship with my teeth, and this feeling might bias my view of dentists. I don’t like going to my dentist’s office every six months and having my teeth cleaned. Recently, as I was sitting in the chair, a thought occurred to me.

I began to wonder if there was such a thing as “evidence-based dentistry.” In my book Super Crunchers (naked self-promotion), I wrote an entire chapter about evidence-based medicine — which is, in part, an effort to test whether medical treatments are statistically proven to be effective. I figured there had to be a parallel movement in dentistry, and maybe someone had analyzed whether hygienist teeth cleaning helps or not.

Thank God for Google. It turns out there is an entire journal called “Evidence Based Dentistry.” And in just a few minutes, I was looking at a formal Cochrane review titled “Insufficient evidence to understand effect of routine scaling and polishing.”

The review looked for evidence to answer two related questions:

The first is, do scale and polish procedures [having your teeth cleaned] lead to any difference in periodontal health compared with no scale and polish? Second, does the interval between these scale and polishing procedures make any difference?

The results were not heartening for those of us who have suffered through dozens upon dozens of cleanings. The meta analysis of qualifying studies suggested that the evidence was mixed, at best. For example, there is not strong evidence that hygienist cleaning reduces gingivitis:

[T]he authors of the only study that found differences in gingivitis scores (at 6, 12 and 22 months) deemed those differences clinically irrelevant….

One reasonable reaction to this is to simply reject the Cochrane review methodology. Evidence-based medicine ranks the quality of different types of evidence — and tends to give inordinate weight to randomized control trials. Indeed, Cochrane reviews often give no weight to the results of any non-randomized clinical study. As the review acknowledges:

[This Review] carries with it the limitation inherent in most of these reviews, of including only randomized clinical trials. For this particular question, the quantity of non-randomized trials identified in the exclusion list suggests that an independent review of this more ‘‘risky” literature might be profitable.

But another reaction is to question whether it is really necessary to put dental patients through so much financial and physical discomfort. Dentists, like other agents (real estate agents, car sales people), do not have the best economic incentives when advising how much to clean.

My dad always told me that dealership rust-proofing was a scam to give dealerships some extra cash without providing your car with any extra protection. Could getting your teeth cleaned be the economic equivalent to having a car dealership rust-proof your car?

Like I said before, this post is probably just working out some wounded inner child issue. (And let me be clear that I’m not calling into question the value of brushing and flossing your teeth, or visiting your dentist regularly to check for cavities, as well as other potential problems). But it’s food for thought. The next time your dentist asks you to make an appointment to have your teeth cleaned, you might reasonably ask, “Why?”


Dental cleanings are necessary. Brushing and flossing do not remove tartar - only plaque. If you wanted to remove tartar you'd need a metal scrapper like the dentist have.

Phil T

#16. Mark, you crack me up!!

The Dental industry is just like any other. You just have to do your homework and shop around for a decent one. Half of them do a good job while the other half are just salesmen -- selling useless and harmful bleaching products.


My comment is a bit outside the debate regarding the need for regular cleanings. My interest is in bringing dental health coverage parity to the masses, similar to mental health coverage parity laws that have passed over the last 10 or so years.

I have spent the last ten years dealing with the repercussions of a bike accident that knocked out my front two teeth out in 1997. When I learned that the work the dentist did had failed by a new dentist in 2004, my parents spent about $20k to cover all the work that had to be done. Much of it was NOT cosmetic - "apical" surgery to clean out lingering infections (what they do if root canals fail, as my did), etc.

Apparently if you have infections in your jaw health insurance doesn't cover it because surgery it's done at an endodontist's office rather than a hospital, making it "dental." Crowns aren't covered if the teeth you are born with crack or are broken in half like one of mine.

More and more links between diseases and dental health, such as heart disease and dental plaque, are being observed by researchers. I think we could better use our energy on dental health parity.



I grew up in Chile, where dentists do not clean your teeth the way you do here, although they still recommend a visit every six months, where they take x-rays to check for cavities. So I never had my teeth cleaned until a couple of weeks ago. They felt clean, although not extraordinarily so. After I got it, it felt like a scam.


I get my teeth cleaned irregularly. At one cleaning the dentist told me I had a cavity and that it would need to be filled. I "forgot" to tell my mother and I moved away to college. I came back to a different dentist who found no cavity. 6 years later and on the third dentist, still no cavity.
I'm glad I didn't pay the dentist to drill a big hole in my molar.

Conclusion: while I like the way my teeth look and feel after a cleaning, I have had less "cavities" since I stopped going to the dentist every six months. If I get any more of them I will be finding a second and perhaps third opinion before excavation.

My dentist used to encourage regular xrays. One day I decided I had enough of that as well as the flouride treatments. When I asked why I needed the xrays, I was told that they could see the cavity forming inside the tooth or below the gum-line. I asked what they did if they discovered a cavity forming. I was told that they would wait until it surfaced and then fill it. Well, I replied then you can just fill it in when you see it and I don't require an xray. I have not had flouride or xrays for many years and no cavities either. I don't floss, and apart from the tartar build up am always told my teeth are healthy. I do quite a bit of tongue brushing which I believe helps and there is more than enough flouride in my water and toothpaste to provide that protection. If I were to pay extra for a particular treatment, I would choose the protective coating that was painted on my children's teeth. I believe there is plenty of evidence to show the benefit of that procedure in children and I think it would go further than flouride or tooth cleaning as far as protection from cavities. But what do I know other than my own experiences?


E to the M

Having lived both below and above the poverty line I am always struck but the disparity of information I receive at the dentist's office. When living above the poverty line I was constantly warned to floss more lest eroding gums lead to serious problems, to brush better, and generally made to feel shame toward the state of my mouth. When living below the poverty line my dental hygiene was praised. Did the dental clinic truly think I possessed good hygiene or were they trying to make me feel better? Did my regular dentist's office really think that my hygiene was subpar or were they trying to sell me on more frequent visits or that bonding they offered?
In the end, it looks like the exact same teeth are good for a poor person but bad for middleclass.


"It's very possible that people who are more likely to get frequent cleanings are those very same people who floss and brush regularly. That would seem to make it difficult to tease out the brush vs. cleaning effect, no?"

That depends. It would make it easier to interpret if there were no significant differences. I'm a bit disturbed by the lack of evidence (citations plzkthnx) being offered by the dentistry reps here.

The Don'tist

I figured the same thing. I recently had a root canal on an infected molar. But when I went to the Dentist, before treating this gaping hole in my jaw, she recommended I spend $300 on a high intensity cleaning. I later thought this was a bit like going to the hospital with a knife sticking out of your chest and then being treated for excess knuckle hair. I have an infected painful tooth! Treat that!


Financially speaking why don't you just have all your teeth pulled out? One and done. Then you won't have to publish ridiculous articles. Think of all the money you'll save on toothpaste, mouth wash, flosh, dates (dinner and movies are expensive), a wedding, a honeymoon or kids. Female companionship is overrated. Yes that is sarcastic.

Paul S.

I think dentists are running a minor scam. They perform a very useful and necessary function, but not at the frequencies they recommend. It takes years to develop a cavity, even in the worst oral hygiene situations.

Anecdotally: I went eight years (from age 22 to age 30) without visiting a dentist. In that time I developed one cavity -- below the gumline adjacent to a void where a wisdom tooth once resided.

I now visit a dentist every 12 to 18 months, depending on my insurance situation. Every time I visit they fret about the imminent demise of my teeth due to advanced scale, gingivitis, gum recession, and good old fashioned decay...none of which has obtained.

I do not have a good genetic history for teeth. My parents both have mouths full of fillings. Three of my grandparents wore dentures. I and my brother have had extensive orthodontia. My teeth are full of chips from bike accidents and opening beer bottles with my teeth. And yet, in 37 years of disinterested dentist visits: one cavity. Which took 8 years to develop. In a place I never brushed.

The outlying variables in my case might be: 1) my parents' insistence on fluoride treatments AND fluoride pills when I was a child, in addition to growing up in places with fluoridated water; and 2) twice-daily brushing and once-weekly flossing, religiously, since I was a teenager. (In fact, several dentists have commented that I brush my teeth "too well," causing gum recession.)

Of course, the plural of "anecdote" isn't "data."



I go to a dental co-operative and they say that cleanings differ by person.
I am genetically predisposed to healthy teeth and take pretty good care of them; so I see my hygienist once a year, mostly just to make sure there are no problems developing.
In fact I rarely see my dentist,which is a shame as he is quite handsome.


I thought that this was common knowledge. I always thought that frequent cleaning could potentially be harmful because it removes enamel (which is also why Consumer Reports' report on toothpaste is useless at best and probably a public disservice).


When I was in high school, my buddy Rex blew my mind by revealing that neither he nor his brother had ever been to the dentist. He said they dutifully brushed their teeth twice a day, and had never had any problems. We lost touch after high school. I'm 29 now, and whenever I get my teeth cleaned I still wonder, "has Rex been to the dentist yet?"

Gene Shiau

Treat the routine cleaning as a value-added marketing strategy, if you will. Even if you have dental insurance, you may have to pay a co-pay for every visit. From the moment you sit in the chair to the moment a routine examination is finished, it may have taken 5 minutes. For the resources you have to spend (making an appointment, finding a parking space, waiting in the office, paying your co-pay, and other associated costs such as babysitting), the dentist's time you receive in return is diminutively small. Thus it becomes a disincentive to visit the dentist in the first place.

On the other hand, if you sit there for 30 minutes having your teeth cleaned and an x-ray taken, and at the end having the dentist come in for a quick examination of your dental health, you the consumer feel like something important has been done and is more willing to pay (even paying more) for the services received.

Sadly, this doesn't seem to apply to unmotivated students and their frustrated teachers.


Mark Nelson

Last time I had my teeth cleaned during my regular visit, I had a lot of nasty staining (apparently brought on by a change in caffeinated beverage type, no names because I need some evidence-based testing on that) that I was not able to clear up at home.

The dental tech was able to completely eradicate it with that super-polisher brush along with the gritty compound they use. Stains all gone.

I love that polishing compound. Even a couple days after the visit, a random chunk of whatever grit they use will shake loose and I'll crunch down on it and go - aaaaaah.
So that was worth it.

On the other hand, why can't I do the same thing at home?


My experiment:

I used to go to the dentist every 6 months for the cleaning and so forth but every time the dentist commented how clean my teeth were (I use and highly recommend Sonicare).

So I didn't go to the dentist for 7 years and went in recently. Dentist comments on how clean my teeth were and did the same 10 minutes of cleaning that he did back when I went every 6 months.


I agree this is somewhat of a scam. Every trip to the dentist results in the same story: floss and brush regularly. I understand those benefits, but to me, it is not worth the discomfort nor the burden of scheduling an appointment every 6 months. I'm not saying do away with dentists, but I am confident that if I show up every 6 years instead of 6 months, I will be given the exact same speech.


FYI: If you start seeing brown stains after you start using the "Crest Pro Health" mouthwash, you might want to look at this:

This of course does not affect everyone, but seems to be something to keep in mind that your mouthwash might be the one that allows your coffee to stain your teeth.


And what about those oil change places. They put a sticker saying you should come back in 3000 miles. My manual says 10,000 miles under normal driving conditions.