We are at the beginning of a new decade, a

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1 Dental Work Force Strategies During a Period of Change and Uncertainty L. Jackson Brown, D.D.S., Ph.D. Abstract: Both supply and demand influence the ability of the dental work force to adequately and efficiently provide dental care to a U.S. population growing in size and diversity. Major changes are occurring on both sides of the dental care market. Among factors shaping the demand for dental care are changing disease patterns, shifting population demographics, the extent and features of third-party payment, and growth of the economy and the population. The capacity of the dental work force to provide care is influenced by enhancements of productivity and numbers of dental health personnel, as well as their demographic and practice characteristics. The full impact of these changes is difficult to predict. The dentist-to-population ratio does not reflect all the factors that must be considered to develop an effective dental work force policy. Nationally, the dental work force is likely to be adequate for the next several years, but regional work force imbalances appear to exist and may get worse. Against this backdrop of change and uncertainty, future dental work force strategies should strive for short-term responsiveness while avoiding long-term inflexibility. Trends in the work force must be continually monitored. Thorough analysis is required, and action should be taken when necessary. Dr. Brown is Associate Executive Director, American Dental Association. Direct correspondence to him at the American Dental Association, 211 East Chicago Avenue, 17 th Floor, Chicago, IL ; phone; fax; brownja@ada.org. Key words: dental work force, demand for dental care, dentists productivity, disease patterns, changes in dental procedures, dental expenditures, dental utilization, regional work force We are at the beginning of a new decade, a new century, and a new millennium. As part of these new beginnings, it is worthwhile to assess again the ability of the dental work force to adequately and efficiently provide dental care to a population growing in size and diversity. This new look at work force issues should aim to develop a flexible strategy to steward the human resources of the dental profession. What is needed is a strategy that, regardless of the times, can be used on an ongoing basis to ensure that the nation will maintain a work force with the skills and cultural competence to provide the care that the nation demands. The following quotes illustrate why a flexible strategy, which provides guidance regardless of times, is important. From 1983: Reduce National Manpower Production Based on: Changing Disease Patterns; Demand and Need for Dental Services; Manpower Availability and Regional Oversupply Strategic Plan, American Dental Association s Report of the Special Committee on the Future of Dentistry, From 1995: After reviewing work force models and projections and their underlying assumptions, the committee found no compelling case, at this juncture, that the overall production of dentists will, in the next quarter century, prove too high or too low to meet public demand for oral health services. Dental Education at the Crossroads: Challenges and Change, Institute of Medicine, Five years later, in 2000: The dentist-to-population ratio is declining, creating concern as to the capability of the dental work force to meet the emerging demands of society and provide required services efficiently. Oral Health in America: A Report of the Surgeon General, In the span of seventeen years, these views have gone from an assessment that the work force may be too large, to an assessment that the work force is about the right size, to an assessment that the work force will likely prove too small. Seventeen years may seem like a rather long time, but a typical dentist will have a career of around forty years. Thus, dentists who graduated in 1983 are very probably still practicing today. Dentists who graduated in 2001 will be practicing until almost the middle of the century. What is needed is a policy responsive enough to accommodate short-term needs but which does not limit longterm flexibility Journal of Dental Education Volume 65, No. 12

2 Demand for Dental Care Because most dental care in the United States is provided through private markets, an assessment of the demand for dental services is important for understanding dental work force issues. 1-3 The demand for dental services is significantly responsive to changes in dental fees the higher the fees, the lower the demand. Other factors that influence the level of demand include income, family size, population size, education levels, prepayment coverage, health history, ethnicity, age, and other conditions. Most factors that positively influence demand for dental care have been expanding. The U.S. economy has grown robustly for most of the past two decades, resulting in an increase in discretionary income among Americans. 4,5 People are becoming more knowledgeable about dental health and what is required to maintain it. As the population has become more affluent and educated, the value placed on oral health has increased. In addition, the desire for esthetic dentistry has grown and will probably continue to do so. All of these factors have enhanced the demand for dental services. Disease levels and trends also are important to obtain a complete view of the conditions influencing the demand for care. Dental caries has been the primary foundation of the demand for dental services in modern times, and dental caries has been declining in almost all segments of the child population and to a lesser degree in adults up to about the age of forty-five years. 1,6,7 With this decline comes a decline in the need for dental services to treat caries. The population forty-five years of age and older experienced caries in substantial amounts during their younger years and will require continued management of the consequences of the original caries. Because of changing disease patterns, the dental sector is going through a transition from a service mix that has been predominately therapeutic to a service mix that will be mostly preventive. As seen in Table 1, prophylaxes and examinations more than doubled between 1959 and 1999, while amalgam restorations declined by 75 percent. 8,9 The decline in amalgams is only partly compensated by an increase during the 1990s in the number of posterior resins and other cosmetic materials provided. A study by Eklund et al. also reports service mix changes. 10 In an insured population, there were marked declines between 1980 and 1995 in restorations, crowns, dentures, and extractions. Endodontic procedures declined in younger patients but were stable or increasing in older patients. Over the same time period, there were increases in diagnostic, preventive, and periodontal services. Changes of this magnitude will have profound effects by reducing the demand for some services and enhancing the demand for others. The total effect of changes in disease patterns is likely to diminish overall demand, but other factors, such as a growing economy, are likely to increase demand. The timing and impact of these factors, in combination, on the demand for dental services are not well understood. Dental Care Expenditures The single best measure of overall activity in the dental market is the total (national) expenditures for dental care. Dental expenditure data are available through the Health Care Financing Administration s (HCFA) Office of the Actuary. This measure of dental activity provides information regarding the total consumption of dental services by the nation as a whole. By 1998, consumption of dental services had reached a total of $53 billion dollars. 11,12 As shown in Figure 1, there has been continual growth in dental expenditures during the past Table 1. Percentage of patients receiving selected dental services from private practitioners in the United States, by year Procedure * Oral Examination 20.1% 27.8% 30.1% 42.8% 45.4% Prophylaxis 19.9% 25.5% 24.9% 38.6% 37.2% Fluoride Treatment 0.9% 4.0% 6.8% 9.8% 10.6% Amalgam, 1 Surface 20.1% 15.9% 8.5% 5.3% 3.0% Amalgam, 2 Surfaces 20.6% 16.4% 9.6% 7.2% 4.0% Crown 1.6% 2.9% 5.2% 5.3% 5.9% Root Canal 1.7% 2.9% 3.2% 2.6% 3.3% Extraction 13.0% 9.8% 5.4% 4.9% 3.7% Resin Anterior 4.4% 4.2% Resin Posterior 1.9% 4.8% *Note that the data for 1999 were derived prior to the publication of the ADA 1999 Survey of Dental Services Rendered report and may, therefore, differ slightly from the published report. December 2001 Journal of Dental Education 1405

3 three decades amounting to a 9 percent increase per year in nominal expenditures and a 3.1 percent increase per year after adjusting for inflation. However, growth has been somewhat different depending on the time period. Between 1960 and 1982, real expenditures (after adjusting for inflation) have grown at an average annual rate of 4.3 percent compared to 1.3 percent per year since This 1.3 percent an- Figure 1. Nominal and real (1998=100) dental expenditures, nual growth is only slightly greater than the rate of increase in the U.S. population, which is 1.1 percent. population that visited a dentist within a year in- While the national expenditure for dentistry is creased substantially during the past four decades. a measure of the total size of the market, the per capita The relatively low rate of growth in expendi- expenditure data indicate the amount of expenditures tures per capita since the early 1980s, combined with being received, on average, across the nation s popu- the increase in the percentage of the population vislation. Again, there were two distinct time trends with iting a dentist, suggests that real expenditures per per capita dental expenditures. From 1960 to 1998, patient may have declined. In fact, it is possible to overall real per capita expenditures increased about use HCFA s per capita dental expenditure data, which twice as fast as the population (1.95 percent annu- relate to the entire population (both utilizers and ally). The growth rate was much greater from 1960 nonutilizers of dental services), and NHIS data, to 1982 (3.10 percent annually). In contrast, the which report the percentage of the population who growth rate was only 0.36 percent annually between visited a dentist, to calculate the trend in per capita 1983 and This growth rate was less than half expenditures among those who received dental care. the rate of the growth in the U.S. population. Thus, This trend has been calculated and displayed in Fig- since the early 1980s, the total size of the dental marure 2. The triangles in Figure 2, representing per paket (i.e., total expenditures) has been driven primatient real dental expenditures, do indeed show a derily by population growth. clining trend since Estimates of the percent of the population visiting a dentist during the previous year have been reported from the National Health Interview Surveys (NHIS) conducted by the Center for Disease Control (CDC). The NHIS estimates of the percentage of the population going to the dentist in the past have ranged from about 35 percent in the late 1950s to about 50 percent in 1980 and 64 percent in Figure 2. Real (1998=100) dental expenditures per capita and per patient, Thus, the percentage of the Millions of Dollars Millions of Dollars 1406 Journal of Dental Education Volume 65, No. 12

4 Table 2. Real (Base=1998) 1987 NMES and 1996 MEPS per capita expenditure data for persons two years of age and older who visited a dentist* 1987 Charges 1996 Charges P-Value Overall $ $ By Age 2 to to to to to * Per capita estimates were derived by ADA staff using NMES (Edwards and Berlin, 1989) and MEPS (Cohen, 1997) data available from the Agency for Healthcare Policy and Research (AHCPR). Another source of data provides similar results. Dental expenditure information was collected with the 1996 Medical Expenditure Panel Survey (MEPS) and the 1987 National Medical Expenditure Survey (NMES). 18,19 These surveys were conducted with large national probability samples. Average nominal dental expenditures (based on those with a visit) increased from $ in 1987 to $ in However, when these expenditures are adjusted for inflation (base=1998), the NMES and MEPS data show a decrease in average expenditures from $ to $ (see Table 2). Declines in inflation-adjusted per capita expenditures between 1987 and 1996 occurred for all age groups, except children two to four years. Class I Preventive and Diagnostic Class II Restorative Class III Rehabilitative Age Group Figure 3. Real (1995=100) cost per user, Class I + II + III procedures In yet another study, Eklund et al. found that the large shift in mix of services from 1980 to 1995 did have an impact on expenditures. 20 For example, restorative procedures per utilizer declined from 1980 to 1995; 10 so did expenditures per utilizer for those procedures. 20 Preventive and diagnostic services increased per utilizer, as did expenditures for those services. Birth cohorts have been affected differently, as shown in Figure 3. The elderly experienced a slight increase in expenditures per utilizer while those younger than forty-five years old have experienced a decrease. As shown in Figure 4, large changes in restorative and rehabilitative dental services are behind age-specific trends in dental expenditures. Younger persons experienced a large decrease in expenditures for such services, while older individuals did not. What will happen with dental expenditures in the future is far from certain. The U.S. population will continue to grow, but it also will age and become more diverse. If the percentage of the population that visits a dentist does not continue to increase at a similar rate and/or expenditures per utilizer continue to decrease, then a decline in real per capita expenditures for the overall population could occur. If that happens, growth in total demand would depend on the population growing at a faster rate than the decline in per capita expenditures. However, many factors could intervene. Economic growth, as well as an increasingly educated population, is likely to provide a stimulus to dental demand. New availability of treatment modalities and a documentation of a causal link between oral disease and some systemic diseases are less certain and their impact on demand is more unsettled. Dental procedures to alter the appearance of individuals may grow in importance. Technical and scientific advances will occur, but their timing and effect on demand are unpredictable. As birth cohorts with different disease patterns work their way through age distribution, December 2001 Journal of Dental Education 1407

5 case mix will shift and have a substantial impact on potential demand. Younger cohorts with less disease will probably require less restorative and rehabilitative services as they grow older. The Dental Work Force It is against this backdrop of change and uncertainty on the demand side of the market that the assessment of the future dental work force strategies must be developed. These strategies are further complicated by multiple factors on the supply side of the market that will affect the capacity to provide dental services. This discussion is presented in more detail in the Future of Dentistry 21 and Studies of Dental Workforce. 22 Numbers of Practicing Dentists Age Group Figure 4. Change in Dental Expenditures related to Class I vs. Class II + III procedures, The number of dental school graduates declined from a high of 5,756 in 1982 to a low of 3,778 in 1993, a decrease of 34 percent. Since 1993, graduates increased steadily to 4,041 in The decline of graduates during the 1980s slowed the rate of growth of practitioners. As shown in Table 3, the number of professionally active dentists and private practitioners increased during the 1990s. However, their growth rates were slightly less than the growth in the U.S. population. As a result, dentist-to-population ratios started declining around 1995 and have continued to decrease. 24 Overall, there has been a 0.91 percent decline in the ratios. Women Dentists Since the mid- 1970s, women have entered dental schools, and subsequently dental practice, in increasing numbers. The expansion of the number of women in dentistry has been one of the major dental work force trends during the last quarter of the past century and will continue during the initial decades of this century. Such a fundamental demographic shift raises questions regarding the effect of that shift on work force requirements. This section will describe similarities and differences between male and female dentists in practice characteristics that could potentially have an impact on work force requirements. According to the ADA census of dentists, Distribution of Dentists, the total number of active private practitioners in the United States increased from 116,208 in 1982 to 152,151 in 1999, a 30.9 percent increase. 25 The number of female active private practitioners increased from 3,029 to 21,960 during this same period, an increase of 625 percent. Figure 5 shows the percent distribution of active private practitioners in the United States by gender. In the early 1970s, there were very few women dentists. By 1982, female dentists comprised 2.7 percent of the dentist work force; by 1999 they comprised 14.4 percent. The increase in female dentists resulted from an increase in female dental school graduates during the same period. Between 1982 and 1999, female dental graduates increased 72.6 percent, from 838 to 1,446, while the overall number of graduates decreased by 23.8 percent (from 5,371 to 4,041). The percentage distribution of graduates by gender is depicted in Figure 6. By 1982, women comprised 15.6 percent of total dental graduates; their percent Journal of Dental Education Volume 65, No. 12

6 Table 3. Census counts and projections of United States resident population, professionally active dentists, active private practitioners, professionally active dentists and active private practitioners per 100,000 United States resident population, Professionally Active Private United States Active Dentists Practitioners Resident Professionally Active Per 100,000 United Per 100,000 United Population Active Private States Resident States Resident Year (in thousands) Dentists Practitioners Population Population , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,049* 153,431* , ,476* 160,318* , ,942* 163,328* , ,076* 166,088* , ,930* 168,528* * Preliminary estimates for 2000, 2005, 2010, 2015, and age increased to 39.2 percent in Since then, the percentage distribution of female graduates leveled off, fluctuating from year-to-year in the high 30 percent range. 23 Even if the trend in percentage of female graduates has stabilized, the number and percent of females practicing dentistry will continue to increase. The ADA s Dental Work Force Model forecasts that 29.2 percent of active private practitioners will be female by 2020 (see Figure 5). 24 Part-Time Practice Figure 5. Percent distribution of active private practitioners in the United States, by gender Among male private practitioners, the percentage that worked part-time (defined here as spending less than 30 hours per week in the office) increased from 10.2 percent in 1987 to 14.7 percent in Among females, the increase was from 26.3 percent to 29.9 percent (see Table 4). Overall, the percentage of those working part-time has increased for both sexes. Although the percentage distribution of part-time dentists is higher among females in all three years, in 1987 it was 2.6 times that of their male counterparts; by 1999, it was only two times as high. 26,27 Further analysis of part-time trends by gender and age revealed that December 2001 Journal of Dental Education 1409

7 Figure 6. Percent distribution of dental school graduates, by gender among the youngest dentists, those less than forty years of age, both males and females exhibited increases in part-time hours. The percentage distribution of part-time female dentists has consistently been five to six times that of their male counterparts during the three survey years. 26,27,28 Intuitively, higher part-time distribution among females less than forty years of age can be related to childbearing and/or childrearing responsibilities. But it can also be related to the age distribution of female dentists within the age category of less than forty years old. Within this age category, female dentists tend to be younger and, therefore, involved in the starting and establishing their practices. These processes can account for the higher part-time distribution. Among those forty to fifty-nine years of age, the percentage of part-time practice for both women and men increased slightly between 1987 and 1994 and has been almost stable between 1994 and Table 4. Percentage distribution of part-time active private practitioners, by gender and age group Male 10.2% 13.6% 14.7% < 40 years old 4.6% 4.9% 5.6% 40 to 59 years old 8.1% 8.7% 8.7% 60 years of age or older 40.5% 42.1% 46.2% Female 26.3% 29.8% 29.9% < 40 years old 25.4% 29.6% 31.3% 40 to 59 years old 27.7% 29.0% 28.6% 60 years of age or older N/A* N/A* N/A* * The number of respondents was too low to report data. For this age cohort, the percentage distribution of part-time female dentists has been about three times that of male dentists. 26,27,28 About percent of male dentists sixty years of age or older have consistently been part-time practitioners between 1987 and There were too few female dentists in this age category to report the percentage working parttime. However, there have been shifts in the age distribution of women dentists during this period. Between 1987 and 1999, the female dentist population has aged (e.g., in 1987, 81.4 percent were less than 40 years of age compared to 46.6 percent in 1999). Therefore, it is likely that this shift in age distribution has resulted in a convergence of the percent of older male and female dentists working part-time. As indicated in the section on dentists productivity below, there is no significant difference between productivity of men and women dentists on an hourly basis. Also, full-time women dentists work as many hours as full-time male dentists. The same is true for part-time men and women dentists. Thus, the major impact of women on the work force is that a larger percentage currently practices part-time. As shown in Table 4, about 30 percent of women dentists and 15 percent of male dentists indicate they work part time. 26,27,28 Currently, 14.4 percent of the dentist work force is female. A rough approximation of the impact of women on work force output is the percentage difference in men and women dentists who practice part-time (15 percent) multiplied by the percent of women in the dentist work force. This calculates to about a 2 percent reduction in total dental output. Even in 2020, the impact of women dentists on output will be comparatively small. Then, 29.2 percent of the dentist work force is predicted to be women. If the current gender difference in part-time practice persists, then in 2020 the impact of women on total output will be less than a 5 percent reduction Journal of Dental Education Volume 65, No. 12

8 Dental Work Force Diversity By the year 2020, the U.S. population is expected to grow to 332,145,221. The rate of growth is expected to be 10 percent per decade from 1990 to During this period, it is anticipated that 55 percent of the growth in the U.S. population will be the result of immigrants and their descendants. Growth will be greatest among Hispanics and African Americans. 29 Since 1990, however, there has been a 23 percent decline in dental school enrollment of Hispanics, African Americans, and Native American students. 30 Asian/Pacific Islanders represented 24.5 percent of first-year enrollees in Consequently, at the very time the U.S. population is becoming increasingly diverse, the future supply of dentists is becoming less representative of the population it will serve. Productivity of Dentists Table 5. Annual growth rates in the U.S. population, dental output, and output per dentist, U.S. Population 1.02% 1.18% 0.96% 0.98% Dental Output 2.95% 5.01% 1.84% 1.80% Output per 1.31% 3.95% -0.13% 1.05% Dentist The supply of dental care services is frequently associated with the number of providers licensed to practice in an area. An additional refinement for work force calculations is the dentist-to-population ratio. The ratio relates the number of dentists to the size of the population. However, the dentist-to-population ratio is a crude determinant of the dental work force needs of a community, especially when making comparisons over time. The ratio implicitly holds constant many factors that affect both the population s need and desire for dental care as well as dentists ability to produce those services. One of the factors that the dentist-to-population ratio holds constant is dentists productivity (i.e., the amount of dental output, measured as real gross billings per hour). Improved productivity means that fewer dentists can produce the same amount of dental services compared to previous years. Ignoring productivity changes is likely to lead to serious miscalculations for work force policy. In their recent study, Beazoglou, Heffley, and Bailit 31 showed that total dental output (total production of dental services) of the dental delivery system tripled between 1960 and 1998, growing at an annual rate of 2.95 percent (see Table 5). Change in dental output results from an increase in the number of dentists or from improved productivity per dentist. Over the entire period, the contributions to the increase in dental output from increases in the number of dentists and in dentists productivity (i.e., the amount of dental output, measured as real gross billings per hour) were almost equal: the number of dentists increased 1.85 times, and dentists productivity increased by 1.64 times. It is useful to divide the period from 1960 to 1998 into three different periods, based on changes in productivity and the number of dentists (see Table 5). During the period from 1960 to 1974, dental output grew much faster than the population: 5.01 percent compared to 1.18 percent annually. The reason for the leap in dental output was the rapid rise in productivity per dentist, which grew at 3.95 percent annually. Growth in the number of dentists was actually less than the growth in population. During the second period, from 1974 to 1991, dental output continued to expand more rapidly than the U.S. population, but the difference was much smaller, 1.84 percent compared with 0.96 percent annually. All of the increase in dental output came from an increase in the number of dentists, which rose at about 2.0 percent annually. Dentists productivity actually declined by 0.13 percent annually because the overabundance of dentists compared with demand for dental care made it difficult for dentists to stay busy. During the period from 1991 to 1998, dental output continued to grow more quickly than the population. However, the growth in dentists productivity had recovered from its stagnant period during the 1980s to expand at 1.05 percent annually. Its contribution to output was equal to that of the increase in the number of dentists. Thus, there are two ways to increase dental services: one through increases in the number of dentists and the other through increases in existing dentists productivity. The two methods are related. If an overabundance of dentists compared with demand occurs, productivity is retarded, slowing the increase in dental output. As the dental market tightens, dentists stay busy, and productivity is enhanced. Improvements in technology enhance productivity, but the December 2001 Journal of Dental Education 1411

9 full impact of technical change will also be affected by market conditions. Appropriate use of staff and office space can enhance dentists productivity. 31 The type of analysis described next will discuss these issues. This analysis is different from the previous discussion of dentists productivity per hour. It is like a recipe for efficient production of dental services given the various factors (such as number of staff, staff hours, office space, etc.) that contribute to changes in dentists productivity. However, the analysis does not indicate which factor is more important in a fundamental sense. Of course, the inputs of dentists are critical, because dental services cannot be produced without dentists. Although this productivity analysis does not measure the productive effect of expanded duties for allied dental personnel, it is valuable because it does indicate, given the existing number of allied personnel (across all general practitioner dental practices), the effect on dentist output if the number of allied personnel were to be changed assuming all other factors remain constant. Several factors contribute to changes in dentists productivity. 31 Table 6 shows the percentage increase in dental output per hour from a 10 percent change in each of these factors separately, holding the other factors constant. For example, a 10 percent increase in dentist hours would increase dental output by 2.92 percent while an increase of 10 percent in dental hygienist hours would increase output by the almost equal amount of 2.74 percent. If more than one factor is changed, their contributions are additive. Thus, 10 percent increases in both dental hygienists and dental assistants hours would increase dental output by 4.02 percent. These productivity enhancements can be realized by increasing the staff hours of these personnel. Moreover, these increases can be realized with the current scope of duties for these personnel, as they exist in the various states. Table 6. Percent change in dental output for a 10 percent increase in an input Dentist Hours 2.92% Hygienist Hours 2.74% Dental Assistant Hours 1.28% Other Staff Hours 1.69% Office Space 1.77% Gender (male = 1) 1.14%* Dentist s Age -0.42%* *Not significant at the 5% level Increasing the number of dentists hours by producing more dentists may not be the most costeffective way to increase productivity and subsequently dental services. Interestingly, once other factors are held constant, neither gender nor age is a significant factor in productivity. Female dentists are just as productive as male dentists. Also, older and younger dentists can produce at the same rate. National Dental Work Force Projections To develop a national dental work force policy, one must understand the productive capacity of the dental work force. One dental work force objective could be to keep the productive capacity of the dental work force constant in relation to the U.S. population in 2020 compared with In 2000: U.S. population was 281,421,906; Active private practitioners numbered 153,431; and, Dentists-per-100,000-population ratio was In 2020, the U.S. population is projected to be 332,145,221. Without factoring in productivity improvements, the required number of active private practitioners to maintain the 54.4 dentists per 100,000 population is 180,995, an increase of 27,564. However, it is extremely improbable that for the next twenty years the growth in the level of dentist productivity would be zero. Therefore, assuming 1) that dentists productivity grows at the same rate between 2000 and 2020 as it did between 1991 and 1998 (i.e., 1.05 percent annually), and assuming 2) the number of dentists in 2020 remained the same as in 2000, the same number of dentists adjusted for productivity would be equivalent to 35,646 additional dentists in 2020, far more than the required 27,564. The national supply of dental services is likely to increase because of enhanced dental productivity. Moreover, there is potential to increase dental output by increasing the number of allied dental personnel working in dental offices. These factors indicate that a major increase in the aggregate number of dentists is probably not necessary at this time. Nevertheless, this issue must be followed continuously so that the nation will be ready to act if circumstances change Journal of Dental Education Volume 65, No. 12

10 Geographic Distribution of Practicing Dentists The distribution of dentists varies substantially by geographic area. Reports indicate specific geographical areas are either currently experiencing or predicting declines in the number of practicing dentists North Dakota anticipates losing 40 percent of its dentists to retirement in the next decade. South Dakota expects that 35 percent of its dentists will retire in the coming decade. Minnesota data indicate that dentist-to-population ratios, which improved through the 1980s, have reverted to 1973 levels in the past decade (Born, 2000). 35 Other states indicate that they have sufficient numbers of practicing dentists, and some states have expressed concerns regarding an overabundance of dentists. There are rather pronounced geographic imbalances in the dental work force. 36 One of the reasons for these geographic imbalances is the rapid shifts that are occurring in the U.S. population, which increased from million to million between 1990 and 2000 a 13.2 percent increase. The largest increases occurred in the western and southern states: Nevada, Arizona, Colorado, Utah, Idaho, Georgia, Florida, Texas, North Carolina, Washington, Oregon, and New Mexico all showed 20.0 percent or greater increases in their populations. Ohio, Rhode Island, Maine, Connecticut, Pennsylvania, West Virginia, and North Dakota showed smaller gains (less than 5.0 percent). Only the District of Columbia lost population, with a decrease of 5.7 percent. Similar to the pattern of population growth, the largest increases in the number of active private practitioners were seen in the western and southern states: Nevada, Utah, Washington, Wyoming, Idaho, Florida, Arizona, North Carolina, South Carolina, Colorado, and Delaware all showed greater than 11.0 percent increases in the number of active private practitioners. Connecticut, Iowa, Wisconsin, Michigan and West Virginia showed less than 1 percent increases in the number of active private practitioners. Minnesota, the District of Columbia, and Missouri lost dentists between 1993 and Although the number of dentists increased nationally and for almost all states, the dentist-to-population ratios declined in about one-half of the states between 1993 and 1999 (see Figure 7). Several rapidly growing states, such as Nevada, Arizona, and Georgia, saw their dentist-to-population ratios decline although they registered large increases in the number of dentists. Their populations were simply growing too quickly for the increase in dentists to keep pace. Other states, such as Minnesota, Missouri, Michigan, Nebraska, and Wisconsin, showed declines in their dentist-to-population ratios even though their populations were not growing as quickly as the na- Figure 7. Percentage change in the dentist-to-population ratio, by state, December 2001 Journal of Dental Education 1413

11 Figure 8. Percentage change in productivity-adjusted dentist-to-population ratios, by state, tional average. The number of active dentists in those states grew little or not at all. Nearly one-half of the states showed an increase in the dentist-to-population ratios. Most of these states have not expressed significant concerns regarding the adequacy of the size of their dental work force. Some have expressed concerns that they may be entering a period of overabundance of dentists. As mentioned before, dentist-to-population ratios are crude measures of the adequacy of the dentist work force and should be used with caution. Clearly, this admonition also applies to regional work force assessments. When the dentist-to-population ratios are adjusted for productivity increases, a different picture emerges (see Figure 8). The productivity-adjusted ratios show an increase in the productive capacity of the dentist per 100,000 population for most states between 1993 and However, some states have lost productive capacity, even with adjustments for increases in productivity. Conclusions Many factors affect the required number of dentists. Aging and demographic changes in the dentist work force need to be carefully evaluated on a continuing basis. Dentists productivity should be monitored. The availability of allied dental personnel is critical. Unless trends change, there could be increasing difficulty in attracting students to dental assisting and dental laboratory technology programs. Retention issues related to dental hygiene could continue unless some action is taken. Demand for dental services also plays an important role in work force requirements. Dental expenditures are the usual measure of the size of the dental market. Predicting growth in per capita dental expenditures is difficult because it depends on the growth in the overall economy, socioeconomic shifts in the population, changes in therapeutic and preventive interventions, and the impact of changing oral disease rates as well as dental fees. If major new funding programs become available or if major new treatment opportunities emerge, per capita utilization may increase. If, as younger Americans grow older, they need fewer dental services because they have experienced less oral disease than earlier generations, per capita utilization may decrease. The same could result if major new preventive breakthroughs materialize. If the demand for dental services grows more rapidly than expected, an increase in the supply of dental care services may be needed to meet that increased demand. Alternatively, if de Journal of Dental Education Volume 65, No. 12

12 mand does not grow rapidly, dental care capacity could be adequate. Currently, the national dentist work force seems to be adequate. Moreover, it can remain adequate if major new programs are not enacted, declines in dental school graduates do not occur, and productivity continues to rise. However, circumstances can change. The nation and the dental profession must follow the national work force trends carefully and be ready to act when circumstances warrant action. Regional work force issues do exist and may become more pronounced in the future if current trends persist. A complicating factor with regional work force analysis is the possible movement of dentists between states. New graduates and young dentists just becoming established may consider movement to states with shortfalls of dentists. Given these widely varying work force conditions among the states, it is apparent that one overall national policy will not fit the specific needs of various states. States with a sufficient number of practitioners will require a different policy than those states in which the number of dentists is declining. Those latter states face potentially serious work force issues that should be addressed with their state-specific needs and circumstances in mind. Given an uncertain future, flexibility is a desirable strategy for work force policy. If more dental capacity is needed in 2020 than available through productivity increases, an attractive work force option is to increase the number of allied dental personnel working with dentists. As mentioned in a previous section, the payoff in productivity would be substantial. This is a cost-effective way to generate additional dental services, without the training expense and long-term commitment necessary to increase the number of dentists. REFERENCES 1. Brown LJ. Contrasting the economic outlook for dentistry and medicine. J Med Pract Management 1989;5: Brown LJ, Lazar V. 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