In its entry for "teeth cleaning," Wikipedia claims that "any general recommendation for a frequency of routine cleaning (e.g. every six months, every year) has no empirical basis." So now I'm considering saving money by skipping the dentist, and just doing my best to brush and floss at home. What do you think?
—Lyle in California
I think I wouldn't bet my teeth on something I saw on Wikipedia. I get it—no one likes being told what to do and when to do it, and that goes double for having the corners of your mouth yanked open while steely implements scrape and prod. And surely there's no reason dental maintenance should be exempt from cost-benefit analysis. But when "being a smart consumer" starts looking too much like "avoiding going to the dentist," it might be time to question your own motives, too.
It's true that current research doesn't offer much guidance. Two scholarly reviews, from 2013 and 2014, looked at the existing data attempting to gauge the effectiveness of routine scaling and polishing, and both sets of authors concluded the same thing: Better studies will be needed before we can say anything concrete about the benefits of professional cleaning, including how often it might be needed.
And the cited source for the Wiki quote you provide—a 2010 post on askthedentist.com, addressing a question similar to yours—more or less lines up with these findings: The twice-a-year cleaning model, it agrees, is arbitrary. But the asked dentist, a reasonable-sounding Bay Area DDS named Mark Burhenne, certainly doesn't take the position that, in general, people are going to the dentist too often. Burhenne's concern is that, given wide variance in brushing/flossing regimens, two cleanings a year might not be often enough for a patient with gingivitis hoping to prevent full-blown periodontitis, or a patient with periodontitis who wants to keep his or her teeth.
After all, teeth cleaning (dental prophylaxis, to use the pros' term) is largely about preventing gums, and eventually the bones your teeth are lodged in, from succumbing to bacterial destruction. The Centers for Disease Control has said that more than 47 percent of Americans aged 30 and up have periodontitis, which is what gingivitis develops into. And while the condition can be prevented, or, once diagnosed, contained to some degree, the damage to gum and bone can't be reversed. Even if you consider your teeth expendable, periodontal disease can have other health impacts: Pregnant women with bad gums, for instance, are more likely to bear low-weight children. If you have insurance covering two annual visits, it's not going to do any harm to schedule those cleanings so your dentist can keep tabs on any developments.
Granted, it wasn't dental-health pros who initially came up with the every-six-months recommendation, or even insurance agency bean-counters—it was ad men. In the 1920s and '30s Pepsodent fought its way to the top of the U.S. toothpaste market largely on the strength of advertising campaigns waged by industry pioneer Claude Hopkins. The brand sponsored a succession of radio shows, including the wildly popular Amos 'n' Andy, and Hopkins dreamed up the slogan that for years led off the broadcasts: "Use Pepsodent twice a day—see your dentist twice a year." When dental insurance came along after WWII, the big insurers seem to have simply adopted the Pepsodent schema outright—again, it's not like they could have based a check-up schedule on actual research, as there wasn't any.
The copywriters on the Pepsodent account (as copywriters will) invented fantastical words to make their humdrum ingredients seem miraculous—the detergent chemical sodium lauryl sulfate became the futuristic-sounding "irium." And of course the company's goals were more mercenary than public-spirited; their campaigns appealed to Americans' vanity, insisting the product removed a disfiguring and embarrassing film from teeth rather than playing up possible health benefits. But you know what? Americans needed to learn to brush their damned teeth. The nation's diet had changed, with the ascent of processed food making sugar and refined flour more prevalent, and tooth decay was rampant. A 1910 survey of 447 schoolkids in Elmira, N.Y., found that only 22 had completely healthy teeth; the rest had 2,063 cavities altogether and required 617 extractions. Toothpaste ads, however shakily conceived, likely did nudge the nation along toward better dental health.
Similarly, encouraging dentist visits at six-month intervals had no scientific basis, but that doesn't make it a bad rule of thumb. For its part, the American Dental Association advises patients that "the frequency of their regular dental visits should be tailored by their dentists to accommodate for their current oral health status and health history." That's a roundabout way of saying that the answer to the question "How often should you see your dentist?" is simple: Ask your dentist. If the response sounds fishy, well, there are lots of other dentists to choose from, and with your teeth on the line, it's worth shopping around for one you trust. A medical professional who's intimately familiar with your in-mouth situation probably knows more about how often you should check in than you do, and certainly more than Wikipedia does.
Send questions to Cecil via straightdope.com or write him c/o Chicago Reader, 350 N. Orleans, Chicago 60654.