Dentist labour force projections 2005 to 2020: the impact of new regional dental schools

Authors


Australian Research Centre for Population Oral Health
School of Dentistry
Faculty of Health Sciences
The University of Adelaide
Adelaide, South Australia 5005
Email: dana.teusner@adelaide.edu.au

Introduction

This report presents updated dentist labour force projections from 2005 to 2020, incorporating several key changes that have occurred since 2000. In recent years there have been substantial increases in dentist labour force recruitment with the establishment of a dental school at Griffith University, the rapid and substantial increase in the numbers of overseas trained dentists entering Australia and ongoing incremental increases in enrolments at existing schools. In addition to these changes, there were announcements in 2007 to establish three new regionally located dental schools. These changes create an imperative to update our projection model for the supply of dentists and dentist visits.

Methods

The model used to project the number of dentists in Australia is based on a dynamic system of stocks and flows. The stock of dentists is equivalent to the number of practising dentists. Inflows into the stock of dentists comprise Australian university dental graduates, migrants into Australia, and dentists who return to practice after a length of absence. Movement out of the stock, or attrition, is comprised of dentists migrating out of Australia and dentists who cease to practice, either temporarily or permanently (Fig 1).

Figure 1.

 Schematic model of recruitment and attrition (source: Teusner et al., 2008).

The baseline number of dentists was derived from the 2005 dental labour force survey, a national survey of all registered dentists that collected information on the characteristics and practice activity of the dental labour force. Practising dentists were categorized into gender and 5-year age groups and, combined with each element of the inflows and outflows, were followed through each category using a basic Markov chain model.1 Numbers of dentists were projected from 2005 through to the year 2020. (For full details of methods and inputs see Teusner et al.2)

Projection model inputs

Baseline number of dentists

In 2005, there were a total of 10 067 practising dentists in Australia of whom 71.6 per cent were male. Approximately one-third (35.4 per cent) of all practising dentists were aged 50 years and over. The age distribution of male dentists differed from the distribution of females; in 2005 only 16.2 per cent of females were aged 50 years and over compared to 43.0 per cent of males (Table 1).

Table 1.   Practising dentists by gender and age group, 2005
Age group (years)Practising dentistsPer cent
MalesFemalesPersonsMalesFemalesPersons
  1. Source: AIHW-DSRU Dental labour force survey, 2005.

20–241361242601.94.32.6
25–2951653610527.218.810.4
30–34748545129310.419.112.8
35–39750442119210.415.511.8
40–44826418124411.514.612.4
45–491131331146215.711.614.5
50–541071270134114.99.413.3
55–59925118104312.84.110.4
60–64565456107.81.66.1
65–69297183154.10.63.1
70–7415341572.10.11.6
75+936991.30.21.0
Total7210285810 067100.0100.0100.0

Recruitment

Recruitment (inflows) into the stock of dentists consisted of five separately estimated components, each component is described below.

Australian university graduates

The number of Australian graduates from Australian dental schools is expected to change dramatically over the first decade of the projection. This is due to the establishment of the Griffith University dental school in 2004 and the planned establishment of three new dental schools (James Cook, Charles Sturt and La Trobe).

The numbers of graduates contributing to recruitment for the first 3 years of the projection (2006 to 2008) were estimated by averaging the number of DEST completions (240) for the years 2003 to 2005. With the first cohort of Griffith University students due to graduate in 2008 and enter the labour force in 2009, coupled with incremental increases in enrolment numbers in most existing schools, the number of graduates per year for the period 2009 to 2013 is expected to increase to 347. As the first cohorts of students from the three new schools enter the workforce in 2014 (anticipated to graduate at the end of 2013), the number of graduates is expected to further increase to approximately 500 graduates (Table 2).

Table 2.   Numbers of Australian graduates from Australian dental schools, DEST completions 2003 to 2005 and estimated numbers 2006 to 2020
 2003200420052006–20082009–20132014–2020
  1. Notes:

  2. 1. Estimates for 2009–2013 and 2014–2020 are based on estimates provided through consultation with Council of Heads of Deans of Dental Schools (CHADDS) members.

  3. 2. There was only one graduate from University of Queensland in 2004 because of the change over to graduate entry. The 2006–2008 estimate for the University of Queensland is the average of the number of graduates for 2003 and 2005.

University of Melbourne 48 45 49 47 70 70
University of Sydney 61 96 44 67 75 85
University of Adelaide 45 34 62 47 58 58
University of Queensland 47 1 43 45 45 50
University of Western Australia 26 44 32 34 45 45
Griffith University 54 70
James Cook University 50
La Trobe University 30
Charles Sturt University 40
Total227220230240347498

Overseas trained dentists (OTDs)

Overseas trained dentists enter the dental labour force via one of two pathways; automatic recognition of qualifications or via assessment by the Australian Dental Council (ADC).

Dentists who obtained their qualifications in the United Kingdom, Ireland or New Zealand are recognized by Australian dental boards and are automatically eligible for registration. Information on the number of dentists who enter via this pathway is currently not available from all jurisdictions. Therefore estimates were derived from international arrivals data collected from passenger cards on entry into Australia (ABS analysis of DIMA, unpublished). This was calculated as the average number of UK, Eire or NZ citizen dentists arriving in Australia each year as long-term visitors between 2000 and 2006. To account for the possibility that not all arriving dentists will practise while in Australia, the estimate was multiplied by the Australian dentist participation rate (84.9 per cent, estimated from the 2005 dental labour force survey).

Dentists who obtained their qualifications in other countries must pass a series of written and practical assessments administered by the ADC. During the 1990s, the number of successful ADC candidates remained stable, an average 35 candidates per year. Between 2002 and 2006, the number increased dramatically from 37 to 158. For the first 3 years of the projection, the actual numbers of successful ADC candidates were known and included in recruitment. From 2008, an arbitrary estimate of 100 ADC candidates per annum was applied. This figure was chosen as a conservative estimate as it is unknown whether recent high levels of applications will continue. In addition, it is anecdotally reported that a number of successful ADC candidates do not go on to reside or practise dentistry in Australia.

Return to practice

The final component of the recruitment vector is the group of dentists who return to practice (RTP). This component includes dentists who return to dentistry after cessation of practice for 12 months or more, and those who return to Australia after an extended visit overseas (more than 12 months).

The estimate for RTP after cessation of practice was derived by tracking the change in work status across years. Not all jurisdictions provide data that can be linked across years. For data sets that could be linked, the percentage of registered dentists who indicated that they were not working in a given year and were employed in the following year was determined (Fig 2). RTP is an age and gender specific rate; total RTP contributing to recruitment is calculated by multiplying the rate by the number of practising dentists in the previous year of the projection.

Figure 2.

 Return to practice rates of practising dentists by gender and age group (source: Teusner et al., 2008).

Estimates for return from abroad were derived from international arrivals data collected from passenger cards on entry into Australia (ABS analysis of DIMA, unpublished). The average number of Australian citizen arrivals, in the period 2000 to 2006, who indicated that they were dentists was used to calculate the return from abroad estimate. This additional RTP component is included to account for dentists who do not maintain their registration in Australia while abroad. There is potential for double counting that cannot be avoided and hence this component is possibly overestimated.

Total recruitment

Taking into account the increase in graduate numbers and increases in the RTP component (resulting from projected growth in the dental labour force), total annual recruitment is expected to increase from 725 dentists in 2005 to 1024 in the year 2020. Graduates from Australian dental schools were the largest component. New graduates comprised one-third (33.1 per cent) of recruitment in 2005 and were anticipated to increase to nearly one-half (48.6 per cent) of all new recruits by 2020 (Table 3).

Table 3.   Recruitment inputs for the dentist projection model
Component2005–20082009–20132014–2020
  1. Source: AIHW analysis of DEST data; Australian Dental Council; ABS unpublished data.

Australian graduates240347 498
Overseas trained dentists
 ADC accreditations 141100 100
 Automatic recognition  57 57  57
Return from abroad 93 93  93
Return to practice194216 276
Total7258131024
 Males380418 514
 Females 345394 509
Total7258131024

Attrition

The attrition component of the model includes dentists who leave the profession either permanently or for an extended break (12 months or more). Attrition was estimated by averaging the percentage of dentists who reported practising in a given year and in the following year reported that they were retired, not practising or were no longer registered. Due to the limited availability of data sets that can be linked across years, attrition rates were based on data from the years 1998 to 2000 from three jurisdictions (SA, VIC and NSW).

For male dentists aged less than 30 years, attrition rates were approximately 5 per cent per year, declining until the 45–49 year age group and then increasing as they approached retirement. For female dentists, attrition rates were stable at approximately 5 per cent until 40 years of age, declined slightly and then increased in the 50 years and over age groups (Fig 3).

Figure 3.

 Attrition rates of practising dentists by gender and age group (source: Teusner et al., 2003).

Results

Projected number of practising dentists

Using the above recruitment and attrition estimates applied in the Markov chain model it was projected that the number of practising dentists would increase substantially from 10 067 in 2005 to 15 042 in 2020. The number of female dentists is projected to double from 2858 in 2005 to 5979 in 2020. In contrast, the number of male dentists is projected to increase by 25.7 per cent, from 7210 to 9063. Taking into account growth in the Australian population, the number of dentists per 100 000 population is also expected to increase from 49.4 to 63.2 (Table 4).

Table 4.   Projected number of practising dentists and practising dentists per 100 000 population, 2005 to 2020
Gender2005201020152020Per cent increase 2005 to 2020
Practising dentists
Males721077368349906325.7
Females2858381548675979109.2
Persons10 06711 55113 21615 04249.4
Dentists per 100 000 population
Total49.453.658.363.227.9
Total capacity to supply dentist visits
Males18.9519.1419.4820.025.7
Females6.168.0910.1712.2699.1
Persons25.1127.2329.6432.2828.6

Figure 4 shows the shift towards a younger age distribution. In 2005, the largest group of dentists were in the 45–59 year age group while in 2020 the largest group is projected to be in the 25–29 year age group. The percentage of practising dentists aged 50 years and over is expected to decline slightly from 35.4 per cent in 2005 to 31.3 per cent in 2020.

Figure 4.

 Age distribution of practising dentists, 2005 and 2020.

Capacity to supply dentist visits

One measure of the supply of dental services is the total number of dental visits, estimated by multiplying the total number of practising dentists by the percentage estimated to be working in clinical practice (96.4 per cent) and by age and gender specific estimates of visits supplied per dentist per year.

Over the past 40 years the number of visits supplied per dentist per year has declined substantially.3 It is unknown whether this trend will continue or whether the decline in visits supplied will plateau. In the current projections it is assumed that the number of visits supplied per year per dentist will continue to decline at half the rate that was observed over the period 1983–1984 to 2003–2004. Table 5 presents the observed and the projected number of dentist visits supplied per dentist per year by gender and age group.

Table 5.   Observed and projected number of visits supplied per year by gender and age group
Age group (years)Observed number of visits supplied per yearProjected annual visits supplied
1983–19841993–19942003–20042020
  1. Source: Longitudinal Survey of Dentist Practice Activity (LSDPA), Teusner et al. 2008.

Males
20–293195295926012077
30–393964308127802038
40–493897372330812794
50–593614308334542970
60+3003241318611423
Females
20–292611272425372427
30–392530241321581969
40–492876269123771965
50–592704309120822100
60+2000316025202578

In 2005 it was estimated that the total number of dentist visits supplied was 25.1 million visits. This is projected to increase to 32.3 million visits by the year 2020. Supply by female dentists is expected to nearly double (a 99.1 per cent increase), in contrast supply by male dentists is expected to increase by only 5.7 per cent (Table 4).

Discussion

The primary aim of this paper was to revise earlier dental labour force projections2,4 by incorporating recent and predicted changes to recruitment as a result of new dental schools, increases in enrolments in existing schools and increases in the number of successful ADC candidates.

The impact of new schools is projected to be substantial in terms of dentist numbers. However, the projected increase in numbers of dentists is not paralleled by the increase in capacity to supply visits. This is primarily due to the assumption that declining productivity, in terms of visits supplied per year per dentist, will continue at half the rate previously observed. However, it is also due to the projected changing gender and age composition of the dentist labour force. Younger male dentists and female dentists have historically provided fewer visits per year than older male dentists. The revised projections assume these observed practice activity patterns will continue and hence the projected shift in the age distribution to a younger labour force and an increased proportion of female dentists have a substantial influence on total aggregate capacity to supply.

What is not known is how these gender and age distribution changes will impact on dental service provision trends. Slight differences in service provision patterns by age and gender have been reported, with rates of preventive treatments provided per visit higher for younger dentists and for female dentists.5 Practice type and sector (public versus private) also vary by gender and age. The proportion of female dentists practising in the public sector is double the proportion of male dentists and younger dentists are less likely to work in solo practice than older dentists.6 As practice factors have also been associated with differences in service provision patterns, it is possible that shifts in labour force gender and age distribution may drive shifts in service provision trends due to differences in service provision patterns, practice type and/or sector of employment.

Furthermore, the practice activity of new graduates trained by new schools may be different again from previously observed patterns, highlighting the necessity to continue dentist practice activity research and to periodically adjust projections of the supply of dentists and dental visits.

Acknowledgements

The authors wish to acknowledge the assistance of the dental boards, state health departments and the responding dentists in the collection of dental labour force data and Dr Robert Broadbent (ADC) for the provision of ADC candidate numbers.

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