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?”
and 
. You can also watch it on 
What you fail to recognize is that dentists often find and diagnose more serious problems, like cavities or gingivitis, during routine cleaning examinations. So even if the cleaning isn’t statistically proven, the tangential benefits make going to a dentist worthwhile.
Hot debate. What do you think?
12 
18
@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.
Hot debate. What do you think?
7 
3
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.
Well-loved. Like or Dislike:
26 
9
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.
but doesn’t a professional cleaning make your teeth look nicer ?
Hot debate. What do you think?
6 
7
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.
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.
Well-loved. Like or Dislike:
14 
3
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.)
Hot debate. What do you think?
7 
5
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?
7 
3
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)
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?
Well-loved. Like or Dislike:
14 
1
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.
Well-loved. Like or Dislike:
21 
1
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.
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.
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?