Dentists seem to have the lowest standards of any profession. Horrifying. No wonder so many commit suicide.
When you’re in the dentist’s chair, the power imbalance between practitioner and patient becomes palpable. A masked figure looms over your recumbent body, wielding power tools and sharp metal instruments, doing things to your mouth you cannot see, asking you questions you cannot properly answer, and judging you all the while. The experience simultaneously invokes physical danger, emotional vulnerability, and mental limpness. A cavity or receding gum line can suddenly feel like a personal failure. When a dentist declares that there is a problem, that something must be done before it’s too late, who has the courage or expertise to disagree? When he points at spectral smudges on an X-ray, how are we to know what’s true? In other medical contexts, such as a visit to a general practitioner or a cardiologist, we are fairly accustomed to seeking a second opinion before agreeing to surgery or an expensive regimen of pills with harsh side effects. But in the dentist’s office—perhaps because we both dread dental procedures and belittle their medical significance—the impulse is to comply without much consideration, to get the whole thing over with as quickly as possible.
The uneasy relationship between dentist and patient is further complicated by an unfortunate reality: Common dental procedures are not always as safe, effective, or durable as we are meant to believe. As a profession, dentistry has not yet applied the same level of self-scrutiny as medicine, or embraced as sweeping an emphasis on scientific evidence. “We are isolated from the larger health-care system. So when evidence-based policies are being made, dentistry is often left out of the equation,” says Jane Gillette, a dentist in Bozeman, Montana, who works closely with the American Dental Association’s Center for Evidence-Based Dentistry, which was established in 2007. “We’re kind of behind the times, but increasingly we are trying to move the needle forward.”
Consider the maxim that everyone should visit the dentist twice a year for cleanings. We hear it so often, and from such a young age, that we’ve internalized it as truth. But this supposed commandment of oral health has no scientific grounding. Scholars have traced its origins to a few potential sources, including a toothpaste advertisement from the 1930s and an illustrated pamphlet from 1849 that follows the travails of a man with a severe toothache. Today, an increasing number of dentists acknowledge that adults with good oral hygiene need to see a dentist only once every 12 to 16 months.
Many standard dental treatments—to say nothing of all the recent innovations and cosmetic extravagances—are likewise not well substantiated by research. Many have never been tested in meticulous clinical trials. And the data that are available are not always reassuring.
The Cochrane organization, a highly respected arbiter of evidence-based medicine, has conducted systematic reviews of oral-health studies since 1999. In these reviews, researchers analyze the scientific literature on a particular dental intervention, focusing on the most rigorous and well-designed studies. In some cases, the findings clearly justify a given procedure. For example, dental sealants—liquid plastics painted onto the pits and grooves of teeth like nail polish—reduce tooth decay in children and have no known risks. (Despite this, they are not widely used, possibly because they are too simple and inexpensive to earn dentists much money.)
…Fluoridation of drinking water seems to help reduce tooth decay in children, but there is insufficient evidence that it does the same for adults. Some data suggest that regular flossing, in addition to brushing, mitigates gum disease, but there is only “weak, very unreliable” evidence that it combats plaque. As for common but invasive dental procedures, an increasing number of dentists question the tradition of prophylactic wisdom-teeth removal; often, the safer choice is to monitor unproblematic teeth for any worrying developments. Little medical evidence justifies the substitution of tooth-colored resins for typical metal amalgams to fill cavities. And what limited data we have don’t clearly indicate whether it’s better to repair a root-canaled tooth with a crown or a filling. When Cochrane researchers tried to determine whether faulty metal fillings should be repaired or replaced, they could not find a single study that met their standards.
“The body of evidence for dentistry is disappointing,” says Derek Richards, the director of the Centre for Evidence-Based Dentistry at the University of Dundee, in Scotland. “Dentists tend to want to treat or intervene. They are more akin to surgeons than they are to physicians. We suffer a little from that. Everybody keeps fiddling with stuff, trying out the newest thing, but they don’t test them properly in a good-quality trial.”
* When physicians complete their residency, they typically work for a hospital, university, or large health-care organization with substantial oversight, strict ethical codes, and standardized treatment regimens. By contrast, about 80 percent of the nation’s 200,000 active dentists have individual practices, and although they are bound by a code of ethics, they typically don’t have the same level of oversight.
* Among other problems, dentistry’s struggle to embrace scientific inquiry has left dentists with considerable latitude to advise unnecessary procedures—whether intentionally or not. The standard euphemism for this proclivity is overtreatment. Favored procedures, many of which are elaborate and steeply priced, include root canals, the application of crowns and veneers, teeth whitening and filing, deep cleaning, gum grafts, fillings for “microcavities”—incipient lesions that do not require immediate treatment—and superfluous restorations and replacements, such as swapping old metal fillings for modern resin ones. Whereas medicine has made progress in reckoning with at least some of its own tendencies toward excessive and misguided treatment, dentistry is lagging behind. It remains “largely focused upon surgical procedures to treat the symptoms of disease,” Mary Otto writes. “America’s dental care system continues to reward those surgical procedures far more than it does prevention.”
“Excessive diagnosis and treatment are endemic,” says Jeffrey H. Camm, a dentist of more than 35 years who wryly described his peers’ penchant for “creative diagnosis” in a 2013 commentary published by the American Dental Association. “I don’t want to be damning. I think the majority of dentists are pretty good.” But many have “this attitude of ‘Oh, here’s a spot, I’ve got to do something.’ I’ve been contacted by all kinds of practitioners who are upset because patients come in and they already have three crowns, or 12 fillings, or another dentist told them that their 2-year-old child has several cavities and needs to be sedated for the procedure.”