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?”

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  1. Gregory says:

    Hidden due to low comment rating. Click here to see.

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    • Clay says:

      @Gregory. The article isn’t questioning the value of regular dental checkups. It’s questioning the value of frequent appointments with dental hygienists. I agree that dental care is important. But I’ve always wondered if there’s any value to scraping hardened substances off my teeth. Perhaps plaque is actually a defensive layer provided by evolution. I’ve looked all over and I’ve yet to see a single study that indicates that dental scaling provides any health benefits.

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      • Suz says:

        I have been a dental hygienist for many years. And hopefully I can explain why routine biofilm and tartar removal is imperative. Evidence based research can actually be done in your own mouth however, at dire consequences. Just don’t get your teeth cleaned for several years and you will have your own petrie dish to do your own experiment. I have seen many of my migrant patients who have never had a cleaning by a dentist or dental hygienist who come to my office with loose teeth, horrible periodontal breath, bleeding gums, and most detrimental to their health -bone loss. If you think about it teeth are the only foreign aspect to our bodies, we have skin that covers us from head to toe and the only foreign body is our hardened enamel, our teeth. Like a fish tank that accumulates “biofilm” so does our teeth. Imagine never cleaning a fish tank, the scum that lingers, smells and eventually kills the fish does the same thing in our mouths. BUT we have to remember that now with advanced research we are finding that plaques in the mouth are having a distinct correlation to systemic health such as heart disease, low birth weight babies, diabetes and some cancers. The hardened tartar is not a natural protection, just look at it under a microscope and you will find over 500 different strains of bacteria. That bacteria starts out creamy on the top of the tooth, and if not properly removed will migrate under the gum tissue where the creamy plaque becomes mineralized. When this happens the bacteria become anaerobic and causes devastation to the underlying bone, and this is evidenced on x-rays. Unfortunately once bone is lost you cannot re-grow it. I cannot stress the importance of regular cleanings to disrupt and remove bacterial colonies. I realize it is a profitable business but so is the Grease Monkey or anywhere else you go to maintain your car. And sometimes we do just that…we prioritize our materials more than our health. Your life is much more important! If you are looking for information that substantiates these claims, please google diabetes and periodontal health, heart disease and periodontal health, periodontal health. As dental hygienists we do our best to educate our patients as to the importance of oral health as well as overall health.

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      • Jen says:

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      • David says:

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      • Not Binary says:

        Much of the bacteria in our bodies, including in our mouth is beneficial to health. Eradicating “99.9%” of these (as Listerine or whatever says it does) could be a very bad thing. Bacteria that cause tooth decay are clearly bad. Bacteria that compete with those bacteria but do not cause tooth decay might be good.

        My educated guess about this the more unnatural your eating habits are (see: insanely refined food products) the more unnatural maintenance like scaling and buffing will be required. Notice that when you’re eating an apple or a handful of oats that almost nothing seems to stick in your teeth for very long. If your diet consists of foods that we were evolved to eat, only very basic oral hygiene should be necessary.

        The other important point is that there is a probably a difference between what we consider “nice looking teeth” and “healthy teeth”. Many would probably say impossibly white (say via bleaching) teeth are the most aesthetically pleasing, yet it’s very unlikely that bleaching is neutral let alone beneficial for anything but this aesthetic.

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      • Andy says:

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      • Mary Helen says:

        Suz the Dental Hygienist. I too worked with migrants in social services and health. Their teeth, mouth, gum problems are NOT the result of no cleaning or would the problems not exist with regular cleanings!! That comment/comparison is so ridiculous!! I did not get regular cleaning for many years. Then I got 2, once a year, for 2 years after my husband’s prodding. That was 2.5 years ago. The money and apin are not worth it and now I find there is no evidence that they are effective– I didn’t think so. I am a researcher and well versed in evidenced-based practice. Good to know I was right!!

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    • Cilica says:

      I think the difference between a cleaning and a check up are mixed up here. You do not have to have your teeth cleaned and horrid florid treatements to have your teech checked. :)

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  2. helen says:

    but doesn’t a professional cleaning make your teeth look nicer ?

    Hot debate. What do you think? Thumb up 41 Thumb down 42
  3. Liam says:

    Does the report check against incidence of gingivitis only, or cavies as well? Further, most dental problems take longer than 6-22 months to show up. I’d rather see a study like this conducted over the course of at least 5 years.

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  4. BriteSmileDave says:

    The last time I visited my dentist was one summer in between college semesters. It had been a while since the prior visit, about 10 years. The hygienist commented that my body chemistry must protect my teeth…or something of the sort. When the dentist came in, after reading my chart, he questioned: “Have you been seeing another dentist?” I thought that that was an odd question, so I responded: “No Doc. I have been faithful to ya!” He did not quite know what to say… Anyway, it has now been about 15 years since that visit to my dentist. I have not seen him since, but I have still been faithful to him. I have never had a cavity, braces, or a retainer. I may be an anomaly, because I never had third molars either.

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    • BriteSmileBack says:

      Funny reading your comments. I have no third molars either and last time I went to the dentist was 6 years ago. Before that I would go religiously to get my teeth cleaned between 4 to 6 months – never missed a cleaning. Every time that I would go, they would remove significant amount of tartar.

      I moved to Jamaica and stopped going to the dentist. Six years later, I feel my teeth clean and without tartar. I have only had one cavity, I don;t floss, but I brush 2X/day very well. I have all my wisdom teeth. But the gap that the missing molars left, i feel created a small space between my teeth to minimize issues.

      I feel that regular cleaning is a scam – but have no proof.

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      • Karin says:

        Sadly I didn’t move to Jamaica but I haven’t been to a dentist for a cleaning in over 20 years. I still have all my teets (except for 2 molars that came out when I was still going to the dentist). I also have all my wisdom teeth, without a problem. My teeth are straight, clean and white so I think it is a big scam! My daughter does go to the dentist but when they phoned today to do a confirmation for an appt. I told them no teeth cleaning and no x-rays. They can just do a check-up and surface cleaning but no prodding and poking under the gums to ‘clean’. Loosening the gums around your teeth seems to be asking for food to come in and settle. X-rays have recently been linked to a very common form of brain cancer so I don’t really think it is neccessary to have my child exposed to that every year. Her dentist said she is very lucky because she has beautiful straight teeth with a perfect bite pattern. Because of that he did want to coat her molars in plastic so they wouldn’t get any cavities. I told him to forget about that. He can get his money for his mortgage somewhere else.

        Sometimes we don’t need proof, but just trust our gut instinct..

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      • Bob says:

        Haha, I got my wisdom teeth removed in JA back in ’98 (a great dentist near crossroads in Kingston, cost about 50$us). I’ve been to see my step mom (a hygienist) a couple of times since and she reports no cavities despite an un-treated chip in a molar I sustained back in 2000. I brush, floss, don’t drink soft drinks and dont take sugar in my coffee. My sister on the other hand has been going every six months for ever and has cavities filled all the time.

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      • Charity says:

        I have had my teeth cleaned 3 times in my life, and I’m 34. I did have my wisdom teeth chiseled out though. I floss a few times a week, brush once or twice a day, and rarely use mouth wash. Last time I went for a cleaning they went so far under the gum for a shadow that the gum peeled away by a incisor and receded. I have descaling tools as home (a gift from my now deceased Nana who was an ER nurse) and I lightly scrape anything away a few times a months. I stopped getting cleanings b/c the last two times I went they spent 5 minutes cleaning, then a half hour trying to get me to bleach my teeth! I drink coffee, tea, and wine. I’m fine with teeth colored teeth. And I still haven’t had a cavity. Could be genetics though…

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  5. Marc says:

    You’re missing the real money issue here. (And, temporarily, I’ll ignore the point that teeth cleaning might not have any benefits.)

    The money charged for a dental cleaning is ridiculous. A dental hygienist can charge a reasonable rate for a dental cleaning, and if allowed to practice alone, probably would. The second a dentist peeks at your teeth (usually, after a ~30 min cleaning, about 2 minutes for a credentialed dentist), the bill doubles.

    1) This causes dental services to be needlessly high; hygienists are capable enough to call in a dentist if needed (similar to the way a family doctor calls in a specialist for a diagnosis).

    2) This causes the actual availability of services to be geographically limited. E.g., not many dental offices near low-income neighborhoods.

    3) Dentists know they made a killing on this, and if ever a legislature brings up the question, they inevitably ask advice from a dental association, which says it’s risky medicine (without any stats to back it up).

    If you want to talk about financial incentives, you’ve got to look at the whole racket.

    (As far as health benefits, the fluoride treatment that typically accompanies a dental cleaning has serious anti-cavity effects.)

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    • Dara says:

      Funny if you think that hygienists would charge any less. And yes they may be able to point out severe cavities and some serious problems…but only some. Hygienists have a very limited education compared to dentists.

      Hot debate. What do you think? Thumb up 44 Thumb down 47
    • jason says:

      I feel that during my cleaning, when they are taking those measurements, they occasionally push so hard that I feel it *pop* which I think somehow opens up my teeth to a future problem – as it feels like soon(ish) after my regular checkup / cleaning is when I get a tooth ache.

      I distrust dentists immense and I change regularly, and I receive the same (poor) treatment from all of them. There seems to me to be too much incentive for them to rip off the insurance (and, therefore, us)

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  6. Mitch says:

    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?

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    • Bob says:

      The article clearly addresses this point — the review article in question ONLY uses randomized control studies, i.e., studies where people are randomly assigned to groups and given cleanings on different schedules. As the article mentions, there are a lot of articles published that do NOT randomize things, and they often find correlations for the reason you mention: people who get more cleanings probably take better care of their teeth in general. But if you randomly assign people to get cleanings on different schedules, you can control for such effects. And, as the article says, the few studies that randomize find no clinically significant effects.

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  7. aurispector says:

    Good home care can not remove calculus (tartar) which is a primary goal of routine cleaning.
    As a dentist, I have some patients that need cleanings every 3 months, some every 2 or 3 years. Your article touches on the difficulty involved in doing good research. Patients will often change their hygeine practice just by being included in a research project. The bottom line is that if you dont feel you need the cleaning, ask your dentist.
    If you don’t like the answer, get a second opinion. Personally I am more wary of any professional who seems more interested in selling services than discussing my health and welfare.

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    • Joan says:

      What you describe is a great reason to have your teeth cleaned. I just konw in our lives the people that do not have their teeth cleaned at all, just checked seem to have no or less cavities and dental problems. I would love to find research on removing healthy bacteria during a cleaning and flouride treatment that effect the ability to reduce or eliminate cavities.

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  8. Mike Scott says:

    If Liam (comment #3) has cavies in his teeth, he has problems that no dentist can help him with. And I rather doubt that checking for guinea pigs is part of the normal scale-and-polish process.

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    • Stephan says:

      I have been having my teeth cleaned on a regularly basis for about eight years now. I feel the more frequent I go for a teeth cleaning, the more quickly my teeth become stained again. I started out going at one year intervals, now I’m down to four month intervals. Is there an explanation for that?

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      • Shannon says:

        Regarding Stephan’s observation that more frequent dental cleanings seem to be associated with an increase in the appearance of stains on his teeth.

        I’ve noticed the same and queried the dental hygienist on that point, but she insisted that that could not be so. I’m not convinced, though – speculating that the action of whatever they use in the cleaning process (can anyone identify that material? or maybe the ultra sound device is responsible) opens the pores of the tooth surface, thereby inviting stains.

        What I’ve also noticed is that I develop sore gums a week or two or three after a dental cleaning. One such spot becomes apparent, then another and another.

        I’ve learned to treat that problem effectively with a sodium hypochlorite rinse – which I saw recommended online by dental microbiologists at a top American university. That approach works within hours, in contrast to no response at all when my dentist prescribed his favourite oral rinse.

        Routinely, though, I use baking soda instead of toothpaste; plus an electric brush, dental floss and a water pik on a daily basis.

        Research is available online which reports that dental floss and brushing isn’t enough to deter gum infections – water piks are recommended by independent researchers. I tried to interest my dentist in promoting water piks for his patients, but he laughed and said that they are too messy. I’ve had concerns about his skill and attention to detail, so last year I changed dentists for the first time in 17 years.

        As a health professional, I have been concerned for years that dental staff do not change their gowns between patients – too expensive, apparently. However, have you ever noticed after being seated in a dental chair that the spotlight above your head – clearly not always cleaned between patients – bears numerous spatters of other people’s tissue?

        That same type of contamination must land on their gowns – on one occasion, I saw the hygienist bump the suction device she was using for me on her gown. I didn’t react quickly enough to prevent her from popping it into my mouth. It was after that incident that I suddenly developed gum infections – yet, at that particualr appointment, I had received praise for the excellent condition of my gums and teeth.

        I doubt that any dentists apply more stringent aseptic techniques – they need to be investigated, but governments defer to their professional associations, who defer to their members. I’ve complained, even to the media, without generating any interest.

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