The Perils of Prediction

In this month’s Charting Progress, Dr. Rick Valachovic urges caution in adopting workforce models and projections that predict a massive oversupply of dentists in 2040, citing the risk and impact of doing so.

Earlier this summer, I was invited to take part in a webinar on the dental workforce hosted by the American Dental Association (ADA). The occasion was the release of a new ADA Health Policy Institute (HPI) brief that presents HPI’s latest estimates of the future supply of U.S. dentists. The study—conducted with the scientific rigor we’ve come to expect from HPI Chief Economist and Vice President Marko Vujicic, Ph.D., and his team—makes an important contribution to the debate about how we, as a dental community, can sustain the dental profession and deliver care to everyone who needs it.

The event provided an opportunity to discuss concerns raised by some in our community about the number of dentists needed for the future. On the one hand, federal workforce projections as late as 2015 concluded that increases in supply would not meet the national demand for dentists in 2025, exacerbating an existing shortage. This assessment, combined with projections about future demand for care, was a factor in the opening of 13 new dental schools and the expansion of many others that we’ve witnessed since 1997.

On the other hand, two of our colleagues in dental education, Howard Bailit, D.M.D., Ph.D., and Stephen “Steve” Ekland, Dr.P.H., D.D.S., M.H.S.A., have predicted a dentist surplus of between 32% and 110% by the year 2040. Writing in the Journal of Dental Education, the authors cite several factors that suggest a decline in demand for dental services and a major increase in the number of people each dentist will be able to serve. While acknowledging the uncertainties in their assumptions, the authors conclude, “[A] large and growing surplus of dentists in 2040 is expected.”

So how do we reconcile these opposing views on the size of the future dental workforce capable of meeting anticipated future demand for care? The authors of the landmark 1995 Institute of Medicine (IOM) report, Dental Education at the Crossroads: Challenges and Change, offered an alternative perspective.

“After reviewing workforce models and projections and their underlying assumptions,” the committee stated, it found “no compelling case that the overall production of dentists will prove too high or too low to meet public demand for oral health services. Accordingly, it found no responsible basis for recommending that the total dental school enrollment should be pushed higher or lower.”

In my view, this assessment is still relevant today and speaks to an essential truth, perhaps best expressed by the inimitable Yogi Berra: “It’s tough to make predictions, especially about the future.”

Yogi was right. Predicting the future is difficult, and we do so at our peril. We don’t know the social, political, technological and other changes that might occur in the near- and long-term future, so any predictions we make are based on uncertain assumptions. Think of the changes that have occurred since 1990—in information technology, genetic engineering and international affairs, to name just a few domains. I chose 1990 because that date was 28 years ago—the same number of years between 2018 and 2040.

What particularly concerns me is the suggestion Howard and Steve make that dental schools should reduce the number of dentists they graduate rather than wait for market forces to reduce the dentist supply. “With a current graduating class of about 6,000 (and growing),” they write, “there is already a substantial surplus of dentists, and this surplus would continue for years to come. Importantly, the longer the current number of graduates continue (or grow), the smaller future classes would have to be to correct the imbalance.”

This statement, like opposing views based on predictions of a dentist shortage, assumes that there is a “guiding hand” able to control with precision the number of dental schools and their class sizes. That may have existed in the health and education ministries in Moscow during the Soviet era, but no government agency or organization has that sweeping influence in the United States. It is a mistake to think that any forces other than market forces can impact these numbers.

Nevertheless, despite the perils of prediction, university presidents and governing boards must make choices about the opening or closing of dental schools, their class sizes and a host of other matters. It seems prudent to me to base those decisions on what we know today about the current state of oral health and the provision of dental services. According to data from the Centers for Disease Control and Prevention, nearly half of all American adults who have teeth have periodontal disease, and nearly half of children under age 19 have experienced dental caries. These numbers are even higher in low-income and minority communities. We could alleviate some of this disease with universal community water fluoridation, but only about 70% of Americans benefit from fluoridated public drinking supplies, and each year some communities vote to remove fluoride from their water. Against this context, for the foreseeable future, we anticipate an ongoing need for dental care.

Public sentiment appears to be bullish on the dental profession. In 2018, U.S. News & World Report placed dentistry number two in its 100 Best Jobs ranking, and number one in its ranking of health care jobs. Our application services data reflect this strong interest in the profession. ADEA currently processes 20 applications for each first-year dental student slot, an impressive ratio that has held consistent for the past six years. We now graduate almost 6,000 dentists annually to serve a U.S. population of 327 million. Contrast that with the mid-1970s, when 6,300 dental graduates went on to serve a U.S. population tallied in 1980 at 226 million. Not surprisingly, no U.S.-licensed dentist who wants to practice his or her profession lacks employment opportunities.

Those who predict doom and gloom for the future of dental education often cite the level of graduating dental student debt as a harbinger of a change in dental education’s fortunes and dentistry’s attractiveness as a career, but we know that there is another story. Dentists have among the lowest default rates on their student loans, and the majority pay off their loans in seven years.

Economic forecasting is an imprecise science at its best. At its worst, it can lead us to set policies that are not in our community’s best interest. Over the decades, we have seen pendulum swings with the opening and closing of dental schools and increases and decreases in the number of dental school graduates. I do not see any evidence that we should try to force the pendulum to one side or the other.

So how do we move forward? The 1995 IOM committee’s conclusion that there is “no responsible basis for recommending that the total dental school enrollment should be pushed higher or lower” strikes me as a solid point of departure. To send a different message to the the university presidents and governing boards of the 66 U.S. dental schools is misguided, in my view. Such a message is also unfair to those current and future applicants to dental school who aspire to a career in dentistry.

As we consider dental school enrollments moving forward, let’s keep the perils of prediction in mind. A world with less dental disease and a need for fewer dentists is well worth aspiring to, but it is far from clear that such a reality is at hand. Intervening to reduce the number of future dental school graduates could harm the millions of Americans with dental disease by impeding the care future graduates could provide. Are we willing to take that risk?