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Suggested Citation:"6 Oral Health." National Research Council. 2011. Research Training in the Biomedical, Behavioral, and Clinical Research Sciences. Washington, DC: The National Academies Press. doi: 10.17226/12983.
×

6
Oral Health

INTRODUCTION

With the publication in 2000 of Oral Health in America: A Report of the Surgeon General,1 the significant impact that oral health can have on overall health and well-being came to widespread public attention. Central to that report’s methodology was its effort to identify: (1) the determinants of health and disease, with a primary focus on factors such as prevention and producing health rather than restoring health; (2) the burden of oral diseases and disorders in the nation as a whole; and (3) the evidence for actions to improve oral health to be taken throughout life. With a strong orientation toward the future, the report emphasized leading-edge technologies and research that could be brought to bear in improving the oral health of individuals and communities. Implicit in its conclusions was a need to support and maintain a biomedical research infrastructure that includes research personnel of sufficient quantity, skill, and inclination to succeed in the task of diminishing oral disease and bringing about the attendant benefits that improved oral health promises for the general health of the U.S. population.

Accordingly, the Surgeon General’s report envisions a biomedical research workforce that could competently address oral diseases and disorders such as dental caries and periodontal diseases; oral mucosal infections and conditions such as oral candidiasis, herpes simplex virus infections, oral human papillomavirus infections, recurrent aphthous ulcers, and oral and pharyngeal cancers and precancerous lesions; and developmental disorders such as craniofacial anomalies caused by altered branchial cleft arch morphogenesis, cranial bone and dental anomalies, craniofacial defects secondary to other developmental disorders, and craniofacial manifestations of single-gene defects. The report also recognized the need for research personnel who could devise new treatments, cures, and diagnostic methods for chronic and disabling conditions such as Sjögren’s syndrome, acute and chronic orofacial pain, and temporomandibular disorders.

Research in areas of human health that have such broad scope and significance cannot rely exclusively on dental researchers as conventionally understood, but rather requires a broader biomedical research workforce that is part of, and fully integrated into, the biomedical sciences generally. Thus, there is no qualitative difference between oral health scientists and other biomedical scientists—only a quantitative need for a sufficient number of researchers who are interested in oral health problems and are willing to direct their attention to this particular field of endeavor. Lacking any intrinsic difference in training between oral health scientists and other biomedical scientists, facile movement of scientists into and out of this particular area of biomedical research should be possible as the nation’s needs warrant.

The 2009 NIDCR Strategic Plan

The principles described in the 2000 Surgeon General’s Report are evident in the recent strategic plan promulgated in May 2009 by the National Institute of Dental and Craniofacial Research (NIDCR).2 That plan embraces the central goal of bringing the best science to bear on problems in oral, dental, and craniofacial health. The plan observes that dental disease itself remains quite common, with dental caries (decay) comprising the most common infectious disease of childhood (Figure 6-1). A constellation of common yet debilitating disorders requires research directed at improved approaches to treatment and prevention. Equally important, however, are technological innovations that promise breakthroughs, such as “labs on a chip,” in which saliva is used as a diagnostic fluid not only for oral conditions, but also for systemic disorders as well. The prospect of bioengineered

1

U.S. Public Health Service. 2000. Oral Health in America: A Report of the Surgeon General. Washington, DC: Department of Health and Human Services.

2

NIDCR. 2009. Strategic Plan 2009-2013. NIH Publication No. 09-7362. Washington, DC: NIH. Available at http://www.nidcr.nih.gov/NR/rdonlyres/79812F51-8893-46BD-AE9D-2A125550533B/0/NIDCR_StrategicPlan_20092013.pdf.

Suggested Citation:"6 Oral Health." National Research Council. 2011. Research Training in the Biomedical, Behavioral, and Clinical Research Sciences. Washington, DC: The National Academies Press. doi: 10.17226/12983.
×
FIGURE 6-1 Dental caries among 5- to 17-year-olds.

FIGURE 6-1 Dental caries among 5- to 17-year-olds.

SOURCE: National Center for Health Statistics, 1996. tissue replacements and molecular imaging tools that utilize

the oral cavity as an exceptionally accessible window into complex biological systems beyond the mouth is no longer a starry ideal, but an increasingly practical reality.

The findings of the 2009 NIDCR strategic plan mirror the thinking of the present committee in terms of its assessment of the national needs for biomedical, behavioral, and clinical research personnel. The direction set by the new NIDCR strategic plan is consistent with the committee’s view of the problems related to the need for researchers in the oral health sciences and reflects both previous (2005) and current committee recommendations in this area.3

Although a tighter integration of research, clinical practice, and health educational communities is essential, it will be equally important to establish and maintain a critical mass of investigators possessing a unique and intimate knowledge of orofacial structures and disorders. Only in that way can schools of dentistry become more competent collaborators in the biomedical research enterprise in the quest to create vibrant research pathways for students and faculty and, ultimately, to improve the health of the public. Recent evidence, however, suggests the reverse trend; that is, a gradual de-emphasis of research in the nation’s dental schools. Figure 6-2 shows the proportion of NIDCR extramural grant support by type of academic institution. Although NIDCR extramural grant support increased by more than 2.6-fold between 1993 and 2008, the percentage of funding going to dental schools decreased from 68.7 percent to 46.7 percent. This suggests that the nation’s dental schools are not competing as effectively for available research dollars in the oral health sciences as are other kinds of academic institutions that have gravitated to dentally related research.

Over the past 50 years the number of dental schools fluctuated between a low of 47 in 1961 and a high of 60 in 1980.4 Between 1982 and 2000, seven dental schools closed—none having a significant research portfolio—and four have opened since 2000, with another eight under consideration for establishment. Of the 12 new and potential dental schools since 2000, 7 are associated with osteopathic medical schools.5 Although these data are viewed in aggregate, it appears that a redirection of dental education away from its historic mission of research, teaching, and service toward a more limited and exclusive focus on teaching may be taking place. This interpretation is corroborated by the decline in the total number of dental faculty members in the biomedical sciences from 933 in 1998 to 663 in 2008 (Figure 6-3).6 This decline of nearly 30 percent in biomedical sciences faculty in dental schools contrasts with the nearly constant number of faculty in the dental and clinical sciences. The implications of this drop are discussed in detail below in the section on faculty shortages.

One factor that may be propelling this trend is a substantial increase in the compensation of practicing dentists, leading to a greater demand for dental education from an expanded pool of academically outstanding dental applicants for whom high compensation is a key driver in the selection of an occupation. Between 2003 and 2008 the overall college grade point average (GPA) of applicants to dental schools increased from 3.43 to 3.55 (see Figure 6-4), and the science GPA increased from 3.34 to 3.47. Existing dental schools have adapted to this market demand by admitting these highly competitive applicants. Moreover, as a further response, a new style of non-research-intensive dental school has emerged.7 Such schools have been founded with a simple, tuition-based, financial plan, often in non-research-intensive universities. Some of these schools do not support a large resident faculty, tenure, or basic scientists. They may have little or no preclinical educational infrastructure and tend not to run large (often money-losing) student clinics or operate research laboratories. As dental schools apparently disengage, research in the oral health sciences has been undertaken by medical schools, engineering schools, hospitals, and other academic institutions.

Obviously research scientists cannot be trained in an environment in which research is not being conducted, and, as a response, the proportion of NIDCR extramural training and career development support going to dental schools decreased from 89.4 percent in 1993 to 73.1 percent in 2008 (Figure 6-5)—again, despite a near doubling of NIDCR support for this purpose.

If this trend is a manifestation of a change in the mission of existing dental schools or a reflection of new dental schools

3

NRC. 2005. Advancing the Nation’s Health Needs: NIH Research Training Programs. Washington, DC: The National Academies Press.

4

IOM. 1985. Personnel Needs and Training for Biomedical and Behavioral Research. Washington, DC: National Academy Press.

5

IOM. 2009. The U.S. Oral Health Workforce in the Coming Decade: A Workshop. Washington, DC: The National Academies Press. See in particular Chapter 4, ”Current Demographics and Future Trends of the Dentist Workforce.”

6

American Dental Education Association, Center for Educational Policy and Resources, 2009.

7

American Dental Association. 2009. Survey of Dental Education, Volume 3: Faculty and Support Staff. Available at https://www.ada.org/sections/professionalResources/pdfs/survey_ed_vol3.pdf.

Suggested Citation:"6 Oral Health." National Research Council. 2011. Research Training in the Biomedical, Behavioral, and Clinical Research Sciences. Washington, DC: The National Academies Press. doi: 10.17226/12983.
×
FIGURE 6-2 Extramural grant support by type of academic institution.

FIGURE 6-2 Extramural grant support by type of academic institution.

SOURCE: NIDCR Strategic Plan, 2009-2013.

FIGURE 6-3 Biomedical science and dental/clinical science full-time equivalent faculty, 1998-1999 to 2007-2008.

FIGURE 6-3 Biomedical science and dental/clinical science full-time equivalent faculty, 1998-1999 to 2007-2008.

SOURCE: American Dental Education Association, Center for Educational Policy and Resources, 2009.

Suggested Citation:"6 Oral Health." National Research Council. 2011. Research Training in the Biomedical, Behavioral, and Clinical Research Sciences. Washington, DC: The National Academies Press. doi: 10.17226/12983.
×
FIGURE 6-4 Average pre-dental GPA of first-year students, 2003-2004 to 2007-2008.

FIGURE 6-4 Average pre-dental GPA of first-year students, 2003-2004 to 2007-2008.

SOURCE: American Dental Association. 2009 (April). 2007-2008 Survey of Dental Education. Volume 2: Tuition, Admission, and Attrition. Chicago, IL: ADA.

FIGURE 6-5 Proportion of NIDCR extramural training and career development support by type of academic institution.

FIGURE 6-5 Proportion of NIDCR extramural training and career development support by type of academic institution.

SOURCE: NIDCR Strategic Plan, 2009-2013.

Suggested Citation:"6 Oral Health." National Research Council. 2011. Research Training in the Biomedical, Behavioral, and Clinical Research Sciences. Washington, DC: The National Academies Press. doi: 10.17226/12983.
×

whose long-term institutional commitment coalesces around teaching the technical aspects of dentistry while minimizing research as the foundation of professional practice, then the decrease in focus on research could well continue over an extended period, undercutting the pipeline of potential research scientists coming from the nation’s dental schools. This will decrease further the amount of research conducted within dental schools, thus strategically weakening the nation’s oral health research infrastructure. Interestingly, should the demand for clinical dental education decline, the market forces that led to the emergence of a new model for dental schools may disappear; however, this does not suggest a return to a more research-oriented educational model. Rather, non-research-intensive dental schools may well be the survivors of a downsizing of the dental educational establishment. Based on high tuition and a robust business plan that excludes the costs associated with basic scientists, research laboratories, preclinical educational infrastructure, large student clinics, or tenured faculty, the newer schools will have far lower fixed expenses. Should demand for dental education decline in the future, it may be research-oriented dental schools that are most likely to close.

The NIDCR Strategic Plan for 2009-2013 recognizes these trends, yet is bold in setting for itself the goals of broadening its scope of inquiry, strengthening the research pipeline, fostering novel clinical research avenues, and eliminating oral health disparities. The NIDCR strategic plan takes a step forward in recognizing the importance of closer integration among research, practice, and education communities with the goal of understanding and ameliorating disorders affecting the oral and craniofacial complex. The NIDCR strategic plan consciously recognizes unique challenges at a time when greater cross-talk, not less, is needed among clinicians, scientists, and educators in order to sustain progress. The question is whether the language and syntax of science required for such cross-talk will be intelligible to the dental clinician of the future.

Whether research in the oral health sciences emanates from the traditional dental community or from other kinds of institutions and organizations is unimportant as long as the best science is brought to bear on the critical questions of oral health. The NIDCR commitment to widening the scope of inquiry and doing so because “diseases have no disciplinary boundaries” is strongly endorsed by the present committee. Such an approach can indeed bring the best science to oral, dental, and craniofacial health through multi-and interdisciplinary collaboration, including the behavioral and social sciences. Where the researchers will come from, if they do not come from the nation’s dental schools, remains an open question; however, astute investigators in many different fields inevitably gravitate to areas that are prioritized to receive funding. Thus, if NIDCR is able to provide support to maintain robust intramural and extramural research programs, researchers from different disciplines, including non-dental researchers, will undoubtedly compete for available dollars in this arena, and the oral health sciences will continue to advance.

As mentioned earlier, while supporting the best science, it does seem prudent also to encourage development of a core of researchers whose interest is, uniquely, in the area of oral health and whose commitment to this field is both continuous and unambiguous. This view is embodied in the NIDCR strategic plan’s goal of strengthening a diverse pipeline of researchers in the field who will constitute a predictable and consistent source of fully committed investigators over the long term. Such individuals are likely to be the most intimately familiar with the nature of oral disease and the opportunities for oral health research. Even if the nation’s dental schools seem less able or interested in competing for dental research dollars, it does not alter the fact that the investigators most committed to this subject area will still come from among the ranks of research faculty in the nation’s dental schools. Assuming that this is the case, finding sufficient numbers of qualified oral health research personnel will be difficult, not only because of a re-purposing of dental education to a more narrow teaching function, but also because of a significant and longstanding shortage of dental school faculty in general.

Although the shortage of biomedical researchers in the oral health sciences and the shortage of dental school faculty may not be completely interdependent, they are almost certainly linked. For a variety of reasons, for the majority of dental students an academic research career is a less attractive career path than private practice. The NIDCR strategic plan addresses the pipeline of researchers dedicated to solving problems in oral, dental, and craniofacial health by envisioning greater collaboration with schools of dentistry, animating interest, and providing clearer pathways for students and faculty interested in research. The plan emphasizes training and career development of individuals and welcomes new disciplines poised to expand oral, dental, and craniofacial research. Accomplishing this task by encouraging vocations in dental education is discussed in detail in the Faculty Shortage section below.

Another goal of the NIDCR strategic plan—and one that is related to the issue of the pipeline of oral health researchers—is innovation in clinical research. One objective within this category is to ensure breadth and depth of the clinical research pipeline, fostering collaboration between oral health care practitioners, clinical scientists, and basic researchers. This area includes opportunities for combined D.D.S./Ph.D. training. According to the NIDCR, dentist-scientists need enhanced opportunities to obtain high-quality postdoctoral training with protected research time to help them become more competitive for independent research awards. Such postdoctoral programs are still relatively uncommon for dentists who have completed Ph.D. training, and, as a result, these research-oriented dentists have had less success in securing research funding. This was recognized and noted 25 years ago in our 1985 predecessor

Suggested Citation:"6 Oral Health." National Research Council. 2011. Research Training in the Biomedical, Behavioral, and Clinical Research Sciences. Washington, DC: The National Academies Press. doi: 10.17226/12983.
×

report, Personnel Needs and Training for Biomedical and Behavioral Research, which stated:

Dentists are faced with a serious disincentive to pursue training as clinical investigators. Whereas the young physician receives a salary and benefits as a hospital resident and subspecialty fellow, similar payment for the newly graduated dentist is limited largely to hospital-based training in oral surgery and oral pathology. Training in the other specialties rarely provides compensation and may indeed require tuition payment by the trainees.8

Although efforts have been made since the publication of that report to place dental specialization trainees on the same footing as medical trainees through the vehicle of the Graduate Medical Education (GME) allocation to hospitals from the Medicare trust, the outcome has been decidedly mixed. More pertinent to the financing of the education of dentists pursuing training in the biomedical sciences is the insight of Grayson Marshall:

NIH financing of D.D.S./D.M.D./Ph.D. programs needs to be encouraged as a high educational priority. To the extent that it is fiscally feasible, dental schools need to enhance stipends for graduate students without, if possible, causing students to lose eligibility for low-interest student loans. In conjoint D.D.S./D.M.D./Ph.D. programs when the clinical degree is awarded before the Ph.D., the NIH needs to be encouraged to permit postdoctoral stipend levels to apply during the post-D.D.S. phase (as opposed to the lower, predoctoral stipend levels). To the extent possible, tuition waivers (or tuition supplements) need to be found to allow most or the entire burden of D.D.S./D.M.D. tuition to be covered.9

In general, the greater assets available to the biomedical community as a whole have made tuition waivers and stipend supplements possible beyond the amounts provided by NIH. This has not been the case under the more constrained financial circumstances of dental schools. Marshall also suggests that supplementary clinical practice might also be a convenient way of helping to partially finance research training. Specifically, he wrote, “It is both natural and exciting for D.D.S./D.M.D./Ph.D. students to look forward to completing the D.D.S./D.M.D. phase of the program and then be allowed to engage in an intramural practice, deriving direct salary supplements from this source. This opportunity offers great motivation to complete the D.D.S./D.M.D. component of the program in as short a time as possible.” He offers an example of a pilot where this was successfully tried, and he further shows that, despite the combined clinical and research elements of the program, highly motivated students “are able, unexpectedly, to complete the D.D.S./D.M.D. component of the curriculum in just four years and that the opportunity to earn practice income provides an exhilarating strategy to cope with the financial struggles dental students pursuing biomedical research training typically encounter. Placing such students into community outreach programs as salaried personnel is also an option.”

Of particular importance is an analysis of training data undertaken by NIDCR to assure that the institute’s research training investment is targeted to best achieve its goals. Surprisingly, it found that trainees supported by individual fellowships are more likely to obtain independent NIH research funding, particularly with respect to R01 grants, than those supported by institutional training grants. An NIDCR study reveals that a significantly higher proportion of faculty with prior NIH career development (K) awards are in full-time employment than are those who had prior NIH training grant or other NIH fellowship award support (T and F awards, respectively). Furthermore, “a recently conducted NIDCR research training program analysis highlighted the troubling pipeline trend that few NIDCR dental school trainees go on to independent research careers: The evidence suggests that dentists are not as successful as those without dental degrees in obtaining independent research funding.” This revelation is as astonishing as it is disturbing. It almost suggests that the dental degree itself (or some antecedent factor that causes an individual to go to dental school) is a direct impediment to success as a researcher in the oral health sciences. Details at this level of specificity (offering individual versus institutional fellowships for instance) and related issues of format and logistics of particular fellowship opportunities provided by NIDCR to dentists seeking research careers may play an unexpected but key role in differentiating what works from what does not.

THE FACULTY SHORTAGE

There are 58 dental schools operating in the United States with roughly 4,800 full-time faculty members (Figure 6-6). This compares with 2,810 full-time faculty members distributed among 52 dental schools in 1969 and a peak of 5,706 full-time faculty members distributed among 60 dental schools in 1982. All schools award the Doctor of Dental Surgery (D.D.S.) degree or the Doctor of Dental Medicine (D.M.D.) degree, the two degrees being functionally equivalent. The number of part-time and volunteer faculty has steadily increased in recent years, from 6,167 in 2001 to 7,320 in 2006. A decision to allocate an increasing number of faculty slots to part-time faculty at the expense of full-time faculty is consistent with an increased emphasis on teaching and a decreased emphasis on research. This conclusion is founded on the reasonable presumption that most NIH-funded research conducted in dental schools is probably performed by full-time faculty. Amplifying the

8

IOM. 1985. Personnel Needs and Training for Biomedical and Behavioral Research. Washington, DC: National Academy Press.

9

G. Marshall, as cited in Bertolami, C.N. 2009. Creating the dental school faculty of the future: A guide for the perplexed. In ADEA, Beyond the Crossroads. ADEA Commission on Change and Innovation (pp. 90-91). Washington, DC: American Dental Education Association.

Suggested Citation:"6 Oral Health." National Research Council. 2011. Research Training in the Biomedical, Behavioral, and Clinical Research Sciences. Washington, DC: The National Academies Press. doi: 10.17226/12983.
×
FIGURE 6-6 Full-time and part-time and volunteer faculty at dental schools, 1997-2007.

FIGURE 6-6 Full-time and part-time and volunteer faculty at dental schools, 1997-2007.

SOURCE: Data for 1997-2003 from ADEA Web site: “Trends in Dental Education” dated 2007. Data for 2004-2006 taken from JDE articles in 2006, 2008. Data for 2007 are estimates provided by ADEA.

effect of this decrease is the nearly 30 percent drop in the absolute number of biomedical science faculty discussed earlier.

The key evidence for a shortage of dentist-scientists is found in the annual number of vacant budgeted faculty positions (Figure 6-7), which totaled 316 such positions in 2007-2008 (see Table 6-1).10 By way of comparison, the corresponding figure was 293 in 1969.11 Although much has been made of the number of vacant budgeted faculty positions as a metric for a faculty shortage, a difference of just 23 when comparing 1969 to 2008 does not seem that impressive over a nearly 40-year time span. What is impressive, however, is that in 1969, of the 293 full-time vacant budgeted positions, 110 were in the basic sciences. By 1984, this number had decreased to 50, and by 2008 it had decreased further to just 18.12 Such a decline could occur either by a rapidity in filling slots or by defunding them. Perhaps both approaches were in play, given some of the striking trends that are apparent over extended periods of time. As mentioned, between 1998 and 2008 the number of biomedical science faculty declined from 933 to 663—a decrease of nearly 30 percent over a 10-year period. Interestingly, there were 1,917 faculty members in basic sciences departments in dental schools in 1982. If this is chosen as the basis for comparison, it results in a dramatic 65 percent drop in biomedical science or basic science faculty in little more than 25 years. Admittedly, this last comparison needs to be made cautiously inasmuch as methodologies may have differed between the two surveying organizations (the American Dental Education Association and the American Dental Association—one looking at biomedical science faculty and the other looking at faculty in basic science departments). Nevertheless, whether viewed from the perspective of vacant slots in the biomedical sciences, the total number of basic science faculty, the proportion of full-time to part-time faculty, or the share of NIDCR funding going to dental schools, it does appear that dental education is moving away from the biomedical sciences in its educational programs.

Two presumed drivers of the difficulty of recruiting and retaining dental school faculty are compensation and student debt.

Compensation

The most recent survey of the net income of dental practitioners published by the American Dental Association in 2009 shows that 91.8 percent of all professionally active dentists are active private practitioners. The net income of dentists in 2006 (the most recent year for which data are available) amounted to $224,190, averaging both general dentists and specialists (Figure 6-8). During the 1990s, the average net income of solo private practitioners increased 78 percent, while the salaries of full-time dental clinical faculty

10

Chmar, J.E., R.G. Weaver, and R.W. Valachovic. 2008. Dental school vacant budgeted faculty positions, academic years 2005-2006 and 2006-2007. Journal of Dental Education 72(3):377.

11

IOM. 1985. Personnel Needs and Training for Biomedical and Behavioral Research. Washington, DC: National Academy Press.

12

If basic science faculty are combined with a group of faculty identified as “research,” the combined total for 2006-2007 would be 54 vacant positions, and the total for 2007-2008 would be 59.

Suggested Citation:"6 Oral Health." National Research Council. 2011. Research Training in the Biomedical, Behavioral, and Clinical Research Sciences. Washington, DC: The National Academies Press. doi: 10.17226/12983.
×
FIGURE 6-7 Number of vacant budgeted faculty positions in U.S. dental schools, 1997-2007.

FIGURE 6-7 Number of vacant budgeted faculty positions in U.S. dental schools, 1997-2007.

SOURCE: Data from 1993-2006 from Okwuji, A. S., E. Anderson, R. Valachovic. “Dental School Vacant Budgeted Faculty Positions 2007-08” Journal of Dental Education, 2009 73:1415-1422.

TABLE 6-1 Vacant Positions by Primary Area of Appointment

Primary Area of Appointment

2006-2007 Vacant Positions

2007-2008 Vacant Positions

Full-time

Part-Time

Total

Full-time

Part-Time

Total

Clinical Sciences

254

38

292

233

41

274

Basic Sciences

24

0

24

18

0

18

Administration

24

0

24

15

1

16

Allied Dental

4

0

4

4

0

4

Research

30

0

30

41

0

41

Behavioral Science

4

0

4

5

1

6

Total Reported

340

38

378

316

43

359

SOURCE: 2006-2007 data from Okwuji, A. S., E. Anderson, R. Valachovic. “Dental School Vacant Budgeted Faculty Positions 2007-08” Journal of Dental Education, 2009 73: 1415-1422; Chmar, J., R.G. Weaver, and R. Valachovic. “Dental School Vacant Budgeted Faculty Positions, Academic Years 2005–06 and 2006–07” Journal of Dental Education 2008 72:370-385.

at the professorial level (assistant, associate, or full) rose by only 25 to 30 percent (see Figure 6-9).13,14

Several factors influence the income of dentists. Dentists in group practices generally have considerably higher income than sole practitioners, and specialists earn considerably more than general dentists. This is potentially important because most dentists pursuing research training beyond dental school, particularly in the form of the Ph.D. degree, have also secured training as specialists in one of the 10 dental specialties. Difference in income as a function of age may also be significant inasmuch as entering either a research career or pursuing research training during the early years after dental school calls into the play the contrast between the income of dental research faculty and the income of early career practitioners, both in terms of the differential in income per se and also as it relates to the long-term impact of compensation

13

Haden, N.K., R.G. Weaver, amd R.W. Valachovic. 2002. Meeting the demand for future dental school faculty: Trends, challenges, and responses. Journal of Dental Education 66(9):1102-1113.

14

ADA. 2009. 2007 Survey of Dental Practice: Income from the Private Practice of Dentistry. Chicago, IL: ADA Survey Center, American Dental Association.

Suggested Citation:"6 Oral Health." National Research Council. 2011. Research Training in the Biomedical, Behavioral, and Clinical Research Sciences. Washington, DC: The National Academies Press. doi: 10.17226/12983.
×
FIGURE 6-8 Net income from private practice of independent dentists, 2002-2006.

FIGURE 6-8 Net income from private practice of independent dentists, 2002-2006.

SOURCE: Tabulation from the American Dental Association. 2008. Survey of Dental Practice. Volume 1: Income from Private Practice of Dentistry 2008. Chicago, IL: ADA.

FIGURE 6-9 Net income from private practice dentists and dental faculty, actual and projected, 1990-2015.

FIGURE 6-9 Net income from private practice dentists and dental faculty, actual and projected, 1990-2015.

SOURCE: Bailit, H.L, T.J. Beazoglou, A.J. Formicola, L.A. Tedesco, L.J. Brown, and R.J. Weaver. U.S. state-supported dental schools: financial projections and implications. 2008. Journal of Dental Education. 72(2 Suppl.):98-109 in: New Models of Dental Education, The Macy Foundation Study, Reconsidering Dental Education: Planning for the Future, p. 103.

and benefits that have been foregone (Figure 6-10). Thus, very early career dentists earn about $200,000 per year and are approaching their peak earning capacity in their early forties—about the same age at which biomedical research scientists secure their own first R01 grant.

In 2001, the average age for all dental faculty was 49.6 years, and the average age for full-time faculty was 50.6 years.15 Furthermore, “Fifty percent of all faculty are

15

Haden, N.K., R.G. Weaver, and R.W. Valachovic. 2002. Meeting the demand for future dental school faculty: Trends, challenges, and responses. Journal of Dental Education 66(9):1102-1113.

Suggested Citation:"6 Oral Health." National Research Council. 2011. Research Training in the Biomedical, Behavioral, and Clinical Research Sciences. Washington, DC: The National Academies Press. doi: 10.17226/12983.
×
FIGURE 6-10 Net income from the primary private practice of independent dentists by age, 2006.

FIGURE 6-10 Net income from the primary private practice of independent dentists by age, 2006.

SOURCE: ADA. 2007. 2007 Survey of Dental Practices. Chicago, IL: ADA Survey Center, American Dental Association.

50 years old or older, and 20 percent (2,266 individuals) are 60 or older.” In a report published in 2008, respondents to a survey indicated that 28 percent were 60 years of age or older, 37 percent were 50 to 59, 20 percent were 40 to 49, and only 15 percent were younger than age 40.16

Debt

Total resident and non-resident costs for all four years of dental school from 1998 to 2008 are shown in Figure 6-11. The cumulative debt of dental graduates and its growth is shown in Figure 6-12. Clearly, the debt burden of dental graduates is substantial and offers a strong incentive to seek the higher paying clinical practice option rather than a career in biomedical research.

A Plausible Approach for the Future: Compensation, Debt, and Integrating the NIDCR Plan

Without underestimating the difficulties of building a robust oral health research infrastructure when trends within the dental profession and dental education are moving in the opposite direction, the NIDCR goals of broadening the scope of inquiry, strengthening the research pipeline, fostering novel clinical research avenues, and eliminating oral health disparities are not unrealistic. This is especially true when viewed in the light of important countertrends. For instance, beyond the obvious rationale of gauging the likely number of dentists entering the workforce to meet the nation’s dental treatment needs, the population of matriculated students in the nation’s dental schools represents the single most likely reservoir of future researchers in the oral health sciences. It is therefore fortunate that the size and quality of the national applicant pool for U.S. dental schools is strong, as evidenced by a nearly 3-to-1 ratio of applicants to available seats. This upward trend in applicants to positions has continued since 2001-2002. Dental education has responded to this demand by increasing the seats in existing dental schools and by opening several new dental schools, which, in aggregate, added up to an overall increase in dental enrollment of more than 500 students for the 10 years between 1998 and 2008. Apart from the implications of this increase for dental care services to the public, this trend enlarges the potential pool from which future researchers might be drawn while simultaneously adding pressure to an already fragile ratio of students to available professors.

Consistent with the increase in dental school enrollment are ADA figures showing that “the overall number of dental school graduates increased by 16.7 percent between 1998 and 2007 (from 4,041 to 4,714),” as can be seen in Figure 6-13.17

Of special note is the growing percentage of dental graduates who seek positions as employees. The prospect of an

16

Haden, N.K., W. Hendricson, R.R. Ranney, A. Vargas, L. Cardenas, W. Rose, R. Ross, and E. Funk. 2008. The quality of dental faculty work-life: Report on the 2007 Dental School Faculty Work Environment Survey. Journal of Dental Education 72(5):514-529.

17

ADA. 2009. 2007-2008 Survey of Dental Education. Volume 1. Academic Programs, Enrollment, and Graduates. Chicago, IL: ADA, p. 46.

Suggested Citation:"6 Oral Health." National Research Council. 2011. Research Training in the Biomedical, Behavioral, and Clinical Research Sciences. Washington, DC: The National Academies Press. doi: 10.17226/12983.
×
FIGURE 6-11 Average total resident and non-resident cost for all four years, 1998-1999 to 2008-2009.

FIGURE 6-11 Average total resident and non-resident cost for all four years, 1998-1999 to 2008-2009.

SOURCE: American Dental Association. 2009 (April). 2007-2008 Survey of Dental Education. Volume 2: Tuition, Admission, and Attrition. Chicago, IL: ADA.

FIGURE 6-12 Average cumulative debt of all dental school graduates, 1990 to 2009.

FIGURE 6-12 Average cumulative debt of all dental school graduates, 1990 to 2009.

SOURCE: Data adapted from the American Dental Education Association. 2010. Journal of Dental Education. 74(9):1011-1016.

Suggested Citation:"6 Oral Health." National Research Council. 2011. Research Training in the Biomedical, Behavioral, and Clinical Research Sciences. Washington, DC: The National Academies Press. doi: 10.17226/12983.
×
FIGURE 6-13 Dental school graduates, 1998-2007.

FIGURE 6-13 Dental school graduates, 1998-2007.

NOTE: ADA surveys of the immediate career plans of graduates are particularly significant (see Table 6-2).

SOURCE: Data adapted from ADA. 2009. 2007-2008 Survey of Dental Education. Volume 1: Academic Programs, Enrollment, and Graduates. Chicago, IL: ADA.

TABLE 6-2 Immediate Plans upon Graduation, by Percentage of Respondents

Immediate Plans

1985

1990

1995

2000

2001

2002

2003

2004

2005

2006

Private Practice

 

 

 

 

 

 

 

 

 

 

Solo

9.4

5.8

5.8

5.5

4

4.7

4.4

4.1

3.7

3.8

Partner/group

14.3

12

11.1

9.5

7.7

8.7

7.4

6

6.1

6.6

Associate/employed

34.4

31.3

32.9

36.5

41.1

38.9

38.5

40.3

41.8

42.1

Total Private Practice

58.1

49.1

49.8

51.5

52.8

52.2

50.3

50.4

51.6

52.5

Advanced Education

23.6

33.4

36

34.1

34.4

35.7

37.1

38.6

38.6

37.8

Teaching/research/admin.

0.9

1

1.1

0.5

0.6

0.5

1.9

0.5

0.8

0.5

Government Service

10.3

11.6

8.9

11

10

9.3

7.6

7.5

6.1

5.9

Undecided

7.2

4.9

4.2

2.9

2.3

2.2

3

2.9

3

3.2

SOURCE: Chmar, J.E., A.H. Harlow, R.G. Weaver, and R.W. Valachovic. 2007. Annual ADEA survey of dental school seniors, 2006 graduating class. Journal of Dental Education 71(9):1241.

immediate (but more modest) income in a salaried position as an associate in an established dental practice clearly has appeal as a debt-payment strategy in comparison with the need to forgo immediate income while seeking additional financing to build an independent dental practice. This trend may actually represent a potential opportunity for directing an interested subset of dental graduates into comparably paying research positions. Specifically, a more granular approach to understanding the impact of differential compensation and student debt as disincentives to biomedical research careers offers a potentially more effective strategy that has not been tried when eliciting interest in research careers among dental students: Ordinarily, comparisons are made between only two career choices: dentist (or specialist) versus academic (professor or researcher). As Charles Bertolami suggests,

One way to address the problems stemming from income differential between dental educators and practicing dentists is to argue that these categories actually encompass three,

Suggested Citation:"6 Oral Health." National Research Council. 2011. Research Training in the Biomedical, Behavioral, and Clinical Research Sciences. Washington, DC: The National Academies Press. doi: 10.17226/12983.
×

rather than two, discrete occupations: dentist (or specialist); professor; and businessperson (understood as owner or proprietor of a practice). Different levels of work, responsibility, and risk distinguish these three jobs.18

Assuming that the blend of work, responsibility, and risk determines compensation, it is important for dental graduates to understand that it is the assumption of higher risk—especially financial risk—that correlates with a greater financial return. Therefore, it is the category of owner or proprietor of a dental practice—in effect, a business person—whose compensation is relatively high that skews the average income of practicing dentists to the higher income brackets when viewed in aggregate. These high aggregated income figures are what graduating dentists have in mind when entering clinical practice. However, as mentioned earlier, the percentage of dental graduates whose immediate plans upon graduation are to become employed dentists is both substantial and increasing, up from 34.4 percent in 1985 to 42.1 percent in 2006 (Table 6-2). That an increasing percentage of dentists is accepting of the idea of being an employee (at a lower income than that of an owner or proprietor, while still meeting student debt obligations) may mean that a significant subpopulation of students exists in dental schools for whom the option of employment not in a private practice but as a dental academic or researcher could be attractive, assuming the compensation is about the same.

Critically, then, the question is not how compensation differs between dental professors and researchers versus practicing dentists, but rather how compensation compares between professors and researchers and the category of employed (non-owner) dentists. Furthermore, how the benefits of being an employee (including retirement and health benefits, paid vacation time, portability, and relative freedom from financial risk)—and not just starting salary—translate into prized values over an entire career becomes a central issue. Dental graduates willing to put personal financial assets at significant risk in the building up and running of a business-based dental practice in return for significant economic reward associated with these risks will find an academic research career relatively unattractive. This may not be the case, however, for the employed dentist who is unable or unwilling to place personal assets at risk. For the person contemplating a career in dental academics, Nash and Brown pose the crucial question: “Are the monetary benefits from dental training large enough to repay all costs of training and yield a positive net return to the dental school faculty member?”19 The comparisons in Figures 6-14 and 6-15 show that a “good part of the differential between faculty compensation and owner/private practitioners can be explained as the premium that the latter receive for accepting the business risk of owning a practice. These risks include capital investment and management risk.” However (and most significant in this discussion), among those dentists choosing to be employees, the lifetime differential in income between faculty members and practitioners is small. It is only when comparisons are made with owners and proprietors of dental businesses that the large differentials in income emerge. “Owning and equipping a dental office is expensive and not risk free…. Illness or accident can end a career before accrued debt is paid off … [and] both the capital risks and management risks must be compensated…. In addition, such owner/proprietors very likely initiate their businesses by first going out to secure a business loan. In contrast, neither employed dentists nor dental school faculty members are asked to make equity investments that require them to begin their careers by assuming yet more debt.” Distinguishing between employee/dentists and owner/proprietor dentists, as suggested by Nash and Brown, may be very useful in communicating research career opportunities to dental students. Although dental faculty positions can never be expected to offer salaries competitive with dentists who are proprietors of a business, the difference is not great between research and faculty dentists and the growing segment of employed dentists. Even in 2006, before the impact of a major economic downturn on the economics of dental practice had materialized, employed dentists earned almost 40 percent less than owner/proprietors. In light of this finding, and to the extent that financial comparisons are made between faculty positions and practice positions, they should be made only among the category of employed dentists: “This is the premium such individuals pay for the kinds of freedoms employees typically enjoy—including paid vacation time, possibly sick time, a lack of assets at risk, and relative ease of moving from job to job or place to place.”

The practical significance of the Nash and Brown analysis is that it might be advantageous not to view the dental student population as homogeneous and undifferentiated. Rather, research careers in the oral health sciences can be credibly marketed to a significant and identifiable subpopulation of dental students: specifically, those with an inclination to accept a long-term position as an employee rather than as an owner/proprietor. Bringing this choice to the awareness of dental students early in their education could have an impact on the appeal of research careers for some students.

Our predecessor report made several observations that are as true today as they were when the report was issued in 2005, including:

  • If education in biomedical research is to be offered to dentists, it needs either to be a part of professional school study or provided as a postgraduate experience.

18

Bertolami, C.N. 2007. Creating the dental school faculty of the future: A guide for the perplexed. Journal of Dental Education, 71(10):1267-1280. American Dental Education Association.

19

Nash, K.D., and L.J. Brown. 2004. Rate of return from a career as dental school faculty. In L.J. Brown and L.H. Meskin, eds. The Economics of Dental Education. Chicago: American Dental Association, Health Policy Resources Center, pp. 41-79.

Suggested Citation:"6 Oral Health." National Research Council. 2011. Research Training in the Biomedical, Behavioral, and Clinical Research Sciences. Washington, DC: The National Academies Press. doi: 10.17226/12983.
×
FIGURE 6-14 Model of estimating the rate of return to an investment in a dental education.

FIGURE 6-14 Model of estimating the rate of return to an investment in a dental education.

SOURCE: Nash, K.D., and L.J. Brown. 2004. Rate of return from a career as dental school faculty. In L.J. Brown and L.H. Meskin, eds. The Economics of Dental Education. Chicago, IL: ADA, Health Policy Resources Center.

FIGURE 6-15 Average earnings of dental specialists in various careers and average earnings of four-year college graduates, by age, 2000.

FIGURE 6-15 Average earnings of dental specialists in various careers and average earnings of four-year college graduates, by age, 2000.

SOURCE: Nash, K.D., and L.J. Brown. 2004. Rate of return from a career as dental school faculty. In L.J. Brown and L.H. Meskin, eds. The Economics of Dental Education. Chicago, IL: ADA, Health Policy Resources Center.

Suggested Citation:"6 Oral Health." National Research Council. 2011. Research Training in the Biomedical, Behavioral, and Clinical Research Sciences. Washington, DC: The National Academies Press. doi: 10.17226/12983.
×
  • Individuals at the high end of the academic distribution are not being attracted to careers in biomedical research.

  • The percentage of dental graduates interested in teaching, research, or administration is small and declining. Few students entering dental school are aware of a career path that includes oral health research, and even fewer consider this option as they complete their training.

  • The reasons for this low interest include the prospects of a high income in dental practice; accumulated high student debt; and a culture in many dental schools, especially among the clinical faculty, that values the technical aspects of dentistry and often marginalizes research.

The 2005 report lamented the fact that competition is great for the highest academic performers graduating from dental school and that the occupational activities most effective at siphoning off the best graduates academically are the various clinical specialties in dentistry. These training programs require anywhere from 2 to 7 years of additional study after dental school. Accordingly, the appeal of studying several more years for a Ph.D. degree to enter a field guaranteed to offer a lower level of compensation does not enter the consciousness of most graduates of dental programs. Although the current situation relative to the research personnel needs in the oral health sciences is about the same as described in the 2005 report, and though a new and disturbing trend has emerged that seems to de-emphasize research in dental schools, the goals of the new NIDCR strategic plan are well suited to addressing the key problems.

Assuming the current university-based model of both educating and employing research scientists in dentistry remains the operative paradigm, a key question is: What will it take to make both teaching and the research integral to a university-based teaching model appealing to the kinds of individuals required by the biomedical research enterprise in the oral health sciences? Implicit in the previous discussion have been the significant impediments to careers in education and research that materialize as a consequence of dental graduate debt and the need to balance salary and working environment.

What dental educators are really doing when they ask dental students to consider a research career is inducing them to make a dramatic break with their settled career aspiration of becoming a dentist. The available population of potential candidates is not only relatively small—fewer than 5,000 nationally—but also prejudicially filtered: All dental students have gone to college where they encountered research scientists. “They know what academic life is all about and understand what it means to be a professor,” Nash and Brown explain. “In deciding to go to dental school, they have consciously rejected the notion of an academic career. The fixity of this idea in a student’s mind—that they are going to be a dentist not a professor—generates a relatively high gradient against which dental educators have to prevail if such students are to be attracted to an academic career in spite of an explicit and antecedent decision against it.”

RECOMMENDATIONS

Clearly, the best science needs to continue to be brought to bear on problems in oral, dental, and craniofacial health. At the same time, however, a critical mass of investigators who possess a special and long-term commitment to research in the oral health sciences must be maintained. With these goals in mind, the committee believes that the following recommendations are consistent with the 2009 NIDCR strategic plan and that they offer a path forward for achieving that plan’s goals, namely, to increase the biomedical research workforce in the oral health sciences in order to bring the best science to bear on problems in oral, dental, and craniofacial health.


Recommendation 6–1: Working through appropriate organizations such as the American Association for Dental Research, the American Dental Education Association, and research-intensive dental schools, the National Institute of Dental and Craniofacial Research must increase efforts to achieve closer integration between schools of dentistry and the broader research, practice, and education communities with the goal of generating new and vibrant research pathways and partnerships for students and faculty.


Recommendation 6–2: Because individual research fellowships have proven more effective in terms of generating long-term research career commitments than institutionally based programs, greater opportunities for independent NIH research fellowship support is encouraged, including K awards, programs to support postdoctoral research for dentists, Ph.D. programs for non-dentists in subject areas relevant to oral health, and programs for internationally trained non-U.S.-citizen dentists seeking Ph.D. and postdoctoral fellowships. Partnerships with other components of the academic health system need to be developed and maintained based on recognition of the value added by the oral health sciences through systems-oriented approaches as already embodied in programs such as the Clinical and Translational Science Award programs and practice-based research networks. All such NIH-sponsored initiatives should explicitly identify a collaborative role for oral health research.


Recommendation 6–3: Ideally, programs need to be developed that offer tuition waivers or supplements, or loan forgiveness, or both, for the dental school component

Suggested Citation:"6 Oral Health." National Research Council. 2011. Research Training in the Biomedical, Behavioral, and Clinical Research Sciences. Washington, DC: The National Academies Press. doi: 10.17226/12983.
×

of combined D.D.S./D.M.D./Ph.D. programs. This would allow most or all of the burden of the D.D.S./D.M.D. tuition to be covered for students who commit to long-term careers in dental research. Enhanced stipends for graduate students should be provided if fiscally feasible without causing students to lose eligibility for low-interest student loans. In conjoined D.D.S./D.M.D.-Ph.D. programs, when the clinical degree is awarded prior to the Ph.D., the NIH needs to be encouraged to permit postdoctoral stipend levels to apply during the post-D.D.S. phase (as opposed to the lower, predoctoral stipend levels). The feasibility of adaptations of the existing Medical Science Training Program (M.D./Ph.D.) model to dental education—including full funding for eight or so years—should be explored.

Suggested Citation:"6 Oral Health." National Research Council. 2011. Research Training in the Biomedical, Behavioral, and Clinical Research Sciences. Washington, DC: The National Academies Press. doi: 10.17226/12983.
×
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Suggested Citation:"6 Oral Health." National Research Council. 2011. Research Training in the Biomedical, Behavioral, and Clinical Research Sciences. Washington, DC: The National Academies Press. doi: 10.17226/12983.
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Suggested Citation:"6 Oral Health." National Research Council. 2011. Research Training in the Biomedical, Behavioral, and Clinical Research Sciences. Washington, DC: The National Academies Press. doi: 10.17226/12983.
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Suggested Citation:"6 Oral Health." National Research Council. 2011. Research Training in the Biomedical, Behavioral, and Clinical Research Sciences. Washington, DC: The National Academies Press. doi: 10.17226/12983.
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Comprehensive research and a highly-trained workforce are essential for the improvement of health and health care both nationally and internationally. During the past 40 years the National Research Services Award (NRSA) Program has played a large role in training the workforce responsible for dramatic advances in the understanding of various diseases and new insights that have led to more effective and targeted therapies. In spite of this program, the difficulty obtaining jobs after the postdoc period has discouraged many domestic students from pursuing graduate postdoc training. In the United States, more than 50 percent of the postdoc workforce is made up of individuals who obtained their Ph.D.s from other countries. Indeed, one can make a strong argument that the influx of highly trained and creative foreigners has contributed greatly to U.S. science over the past 70 years.

Research Training in the Biomedical, Behavioral, and Clinical Research Sciences discusses a number of important issues, including: the job prospects for postdocs completing their training; questions about the continued supply of international postdocs in an increasingly competitive world; the need for equal, excellent training for all graduate students who receive NIH funding; and the need to increase the diversity of trainees. The book recommends improvements in minority recruiting, more rigorous and extensive training in the responsible conduct of research and ethics, increased emphasis on career development, more attention to outcomes, and the requirement for incorporating more quantitative thinking in the biomedical curriculum.

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