- Top of page
Background: There is limited information on the impact of poor oral health on Indigenous Australian quality of life. This study aimed to determine the prevalence, extent and severity of, and to calculate risk indicators for, poor oral health-related quality of life among a convenience sample of rural-dwelling Indigenous Australians.
Methods: Participants (n = 468) completed a questionnaire that included socio-demographic, lifestyle, dental service utilization, dental self-care and oral health-related quality of life (OHIP-14) factors.
Results: The prevalence of having experienced one or more of OHIP-14 items ‘fairly often’ or ‘very often’ was 34.8%. The extent of OHIP-14 scores was 1.88, while the severity was 15.0. Risk indicators for having experienced one or more of OHIP-14 items ‘fairly often’ or ‘very often’ included problem-based dental attendance, avoiding dental care because of cost, difficulty paying a $100 dental bill and non-ownership of a toothbrush. An additional risk indicator for OHIP-14 extent was healthcare card ownership, while additional indicators for OHIP-14 severity were healthcare card ownership and having had 5+ teeth extracted.
Conclusions: Risk indicators for poor oral health-related quality of life among this marginalized population included socio-economic factors, dentate status factors, dental service utilization patterns, financial factors and dental self-care factors.
- Top of page
Indigenous Australians are those who identify as being of Aboriginal and/or Torres Strait Islander descent, and comprise 2.5% of the population.1 In 2006, the median age of the Indigenous population was 20 years, compared with a median age of 37 years among non-Indigenous Australians. By proportion of population, more Indigenous Australians reside in regional or remote locations, e.g., 45% in inner and outer regional areas, and 24% in remote and very remote locations.1
Indigenous Australians experience substantial disadvantages relative to their non-Indigenous peers, including disparities in income and wealth, education, employment, housing and living conditions.2 Indigenous Australians across all age groups die earlier than non-Indigenous Australians, and are more likely to suffer from ill health, and to experience disability and reduced quality of life.3 They experience much higher levels of diabetes mellitus, cardiovascular disease and kidney disease, and are more likely to be exposed to, or to experience, co-morbidity and other risk factors associated with chronic disease.4 The prevalence of many diseases increases with remoteness and, compared with non-Indigenous Australians, the Indigenous population experiences disease and risk-factors at an earlier age.4 Due to the strong correlations between socio-economic status and exposure to health risk-factors,5 socio-economic inequalities may account for the disproportionate rates of ill-health, disability and reduced quality of life experienced by many Indigenous Australians.4
Currently, there is a shortage of representative, national-level epidemiological data to inform a complete understanding of the oral health of the Indigenous Australian population. However, available data suggest that the disparities in Indigenous and non-Indigenous general health are paralleled in oral health. For example, in the second National Survey of Adult Oral Health, Indigenous Australians experienced 2.3 times the prevalence and 3.4 times the severity of untreated dental decay, and 1.3 times the prevalence of moderate/severe periodontal disease.6 Rates of edentulism and tooth loss were also higher among the Indigenous population.
Although Indigenous Australians have been identified as having poorer clinical oral health outcomes relative to their non-Indigenous counterparts, there is limited information on the impact that poor oral health has on their quality of life. The aims of this study were: (i) to determine the prevalence, extent and severity of poor oral health-related quality of life as measured by the shortened version of the Oral Health Impact Profile (OHIP-14); and (ii) to calculate risk indicators for poor oral health-related quality of life among a convenience sample of Indigenous Australians residing in Port Augusta, South Australia.
- Top of page
Complete questionnaires were obtained from 468 participants, 63% of whom were female. The average age was 38 years, with an age range of 17 to 72 years. The prevalence of one or more OHIP-14 items rated ‘fairly often’ or ‘very often’ was 34.8%. The extent (mean number of OHIP-14 items experienced ‘fairly often’ or ‘very often’) was 1.88, while the severity (mean OHIP-14 score) was 15.0.
The prevalence of one or more OHIP-14 items rated ‘fairly often’ or ‘very often’ was higher among those aged 38+ years, who reported currently or previously smoking tobacco or consuming alcohol, who reported having no remaining teeth and who reported having received five or more extractions (Table 1). OHIP-14 extent was higher among those with a healthcare card and those reporting having received five or more extractions. OHIP-14 severity was greater among those aged 38+ years and among those reporting five or more extractions.
Table 1. OHIP-14 by socio-demographic, substance use and dentate status factors
|Total||34.8 (27.5–42.1)||1.88 (1.55–2.21)||15.00 (13.70–16.30)|
| 37 years or less||29.9 (24.1–35.7)*||1.61 (1.18–2.04)||13.24 (11.47–15.01)*|
| 38 years or more||39.7 (33.5–45.9)||2.16 (1.67–2.64)||16.76 (14.93–18.59)|
| Male||31.1 (24.1–38.1)||1.60 (1.09–2.12)||14.11 (12.00–16.23)|
| Female||36.9 (31.5–42.3)||2.04 (1.62–2.46)||15.50 (13.89–17.10)|
| Port Augusta||34.1 (29.6–38.6)||1.94 (1.59–2.29)||14.96 (13.59–16.32)|
| Other||42.5 (27.3–57.7)||1.30 (0.60–2.00)||15.50 (11.92–19.08)|
| Primary or Secondary school||35.1 (30.4–39.8)||1.87 (1.52–2.23)||14.72 (13.31–16.13)|
| Trade, TAFE, University||33.7 (23.6–43.8)||1.94 (1.16–2.72)||16.31 (13.27–19.36)|
| Job||31.3 (23.8–38.8)||1.44 (0.95–1.93)||14.78 (12.68–16.88)|
| Welfare||36.4 (31.2–41.6)||2.08 (1.67–2.50)||15.10 (13.50–16.70)|
| Yes||36.8 (31.8–41.8)||2.13 (1.73–2.53)*||15.68 (14.14–17.22)|
| No||28.9 (20.6–37.2)||1.13 (0.67–1.60)||13.01 (10.85–15.17)|
|No. of people who stayed in house last night|
| Four or less||36.1 (30.6–41.6)||1.91 (1.51–2.32)||15.36 (13.71–17.01)|
| Five or more||32.8 (26.0–39.6)||1.84 (1.30–2.38)||14.43 (12.40–16.46)|
| Yes||33.3 (26.7–39.9)||1.59 (1.12–2.06)||14.64 (12.75–16.52)|
| No||35.9 (30.3–41.5)||2.09 (1.64–2.53)||15.26 (13.53–16.99)|
| Currently or previously||37.4 (32.4–42.4)*||1.93 (1.57–2.30)||15.27 (13.81–16.72)|
| Never||27.0 (18.9–35.1)||1.73 (1.04–2.42)||14.19 (11.49–16.90)|
| Currently or previously||36.6 (31.8–41.4)*||1.87 (1.52–2.21)||15.35 (13.98–16.71)|
| Never||26.3 (16.7–35.9)||1.96 (1.07–2.86)||13.34 (9.84–16.83)|
|Own teeth left?|
| Yes||33.4 (29.0–37.8)*||1.83 (1.50–2.16)||14.79 (13.48–16.11)|
| No||60.0 (40.9–79.1)||2.92 (1.31–4.53)||18.68 (13.10–24.26)|
| Four or less||36.4 (30.0–42.8)*||1.86 (1.40–2.33)*||15.81 (13.99–17.64)*|
| Five or more||50.0 (39.6–60.4)||2.85 (1.96–3.74)||20.66 (17.64–23.68)|
There were a number of dental service utilization, dental anxiety and dental self-care factors related to oral health related quality of life. For example, the prevalence of one or more OHIP-14 items rated ‘fairly often’ or ‘very often’, OHIP-14 extent and OHIP-14 severity were higher among those who last visited a dentist because of a problem, who avoided dental care because of cost, who reported a lot of difficulty paying a $100 dental bill and non-ownership of a toothbrush (Table 2). OHIP-14 prevalence was additionally higher among those who had visited a dentist before and among those who had not brushed their teeth the previous day. OHIP-14 prevalence, extent and severity was higher among those who perceived a need for a restoration or extraction, who perceived that they had gum disease, who rated their general health as ‘fair or poor’ or who rated their oral health as ‘fair or poor’ (Table 3).
Table 2. OHIP-14 by dental service utilization, dental anxiety and dental self-care
|Previously visited a dentist|
| Yes||36.2 (31.7–40.7)*||1.96 (1.62–2.30)||15.68 (14.34–17.01)*|
| No||20.0 (7.7–32.3)||1.08 (0.09–2.06)||7.80 (3.89–11.71)|
|Last visit to dentist|
| Less than one year ago||36.7 (29.4–44.0)||2.17 (1.58–2.76)||16.37 (14.14–18.59)|
| More than one year ago||35.5 (29.8–41.2)||1.86 (1.43–2.28)||15.33 (13.66–17.00)|
|Location of last visit to dentist|
| Pika Wiya or Public Health Dentist||35.0 (28.7–41.3)||1.93 (1.46–2.40)||15.48 (13.63–17.32)|
| Private Dentist||36.8 (30.3–43.3)||1.99 (1.49–2.49)||15.80 (13.86–17.73)|
|Reason for last visit to dentist|
| Problem||42.7 (37.2–48.2)*||2.39 (1.95–2.83)*||18.40 (16.80–20.00)*|
| Check-up||19.4 (12.5–26.3)||0.92 (0.46–1.38)||8.89 (6.92–10.86)|
|Avoid dental care because of cost|
| Yes||45.5 (36.2–54.8)*||2.84 (2.29–3.39)*||19.16 (17.17–21.15)*|
| No||23.2 (11.7–34.7)||0.85 (0.55–1.15)||10.48 (9.08–11.88)|
|Difficult to pay a $100 dental bill|
| None, Hardly any, a little||28.7 (23.1–34.3)*||0.65 (0.21–1.09)*||9.38 (7.18–11.57)*|
| A lot||41.5 (35.1–47.9)||2.14 (1.76–2.52)||16.16 (14.71–17.61)|
|Scared about dental visit|
| ‘No’||35.2 (29.6–40.8)||1.69 (1.30–2.08)||13.95 (12.35–15.55)|
| ‘A little bit’, ‘a fair bit’, or ‘heaps’||34.4 (27.8–41.0)||2.16 (1.60–2.71)||16.48 (14.38–18.57)|
| Yes||33.1 (28.5–37.7)*||1.66 (1.33–1.98)*||14.30 (12.98–15.62)*|
| No||44.4 (33.0–55.8)||3.14 (2.04–4.23)||18.89 (14.90–22.88)|
|If yes, brushed previous day|
| Yes||32.1 (23.4–40.8)||1.60 (1.25–1.95)||13.73 (12.33–15.13)*|
| No||36.8 (17.8–55.8)||2.18 (1.23–3.13)||17.74 (14.15–21.33)|
|If yes, use toothpaste|
| Yes||33.6 (25.4–41.8)||1.73 (1.40–2.06)||14.36 (12.98–15.74)|
| No||25.0 (0–63.1)||1.50 (0–3.19)||14.70 (7.75–21.65)|
Table 3. OHIP-14 by dental perceptions and self-rated health
|Perceived need for restoration or extraction|
| Yes||48.2 (42.1–54.3)*||2.79 (2.29–3.30)*||20.00 (18.21–21.78)*|
| No||17.6 (12.4–22.8)||0.76 (0.44–1.08)||8.72 (7.23–10.20)|
|Think you have gum disease?|
| Yes||55.6 (45.9–65.3)*||4.19 (3.22–5.16)*||27.19 (24.31–30.07)*|
| No||28.7 (24.1–33.3)||1.23 (0.95–1.52)||11.55 (10.32–12.78)|
|Self-rated general health|
| Excellent, very good, or good||29.9 (25.1–34.7)*||1.45 (1.12–1.78)*||12.81 (11.42–14.19)*|
| Fair or poor||48.4 (39.6–57.2)||3.10 (2.32–3.88)||21.10 (18.43–23.77)|
|Self-rated oral health|
| Excellent, very good, or good||24.4 (19.5–29.3)*||1.03 (0.73–1.33)*||10.78 (9.46–12.10)*|
| Fair or poor||52.6 (45.2–60.0)||3.34 (2.68–4.00)||22.20 (19.93–24.47)|
In multivariate modelling, risk indicators for OHIP-14 prevalence, extent and severity included last visiting a dentist because of a problem, avoiding dental care because of cost, reporting a lot of difficulty paying a $100 dental bill and non-ownership of a toothbrush (Tables 4 and 5). An additional risk indicator for OHIP-14 extent was ownership of a healthcare card, while additional risk indicators for OHIP-14 severity were ownership of a healthcare card and having had five or more teeth extracted.
Table 4. Poisson regression of OHIP-14 prevalence
| ||Prevalence ratio (95% CI)|
|Last dental visit because of a problem||1.90 (1.30–2.79)|
|Avoid visiting dentist because of cost||1.64 (1.24–2.16)|
|Difficulty paying $100 dental bill||1.34 (1.05–1.72)|
|Non-ownership of a toothbrush||1.37 (1.03–1.81)|
Table 5. Linear regression of OHIP-14 extent and severity
|B (se)||B (se)|
|Ownership of healthcare card||1.26 (0.39)||4.72 (1.73)|
|5+ teeth removed||–||3.32 (1.63)|
|Last dental visit because of a problem||1.02 (0.37)||4.92 (1.87)|
|Avoid visiting dentist because of cost||1.93 (0.34)||7.87 (1.53)|
|Difficulty paying $100 dental bill||0.74 (0.33)||3.88 (1.52)|
|Non-ownership of a toothbrush||1.45 (0.50)||6.25 (2.25)|
- Top of page
This study set out to determine the prevalence, extent and severity of poor oral health-related quality of life among a convenience sample of rural-dwelling Indigenous adults, and to calculate risk indicators for the same. Risk indicators included socio-economic factors such as ownership of a healthcare card, dentate status factors such as multiple missing teeth, dental service utilization patterns such as last visiting a dentist because of a problem, financial factors such as delaying dental care because of cost and having difficulty paying a $100 dental bill, and dental self-care factors such as non-ownership of a toothbrush.
Before discussing the findings in more detail, it is important to acknowledge the study’s limitations. This was a convenience investigation, meaning findings cannot be assumed to be representative of the broader Port Augusta Indigenous community, or indeed the Indigenous population at a state or national level. The cross-sectional study design also means that true causality cannot be ascertained. Shortcomings aside, this was one of the largest self-report investigations to be conducted among an Indigenous population within the oral health-related quality of life context. As such, the findings may be helpful in highlighting areas where future research and policy making efforts might be directed.
It is concerning that the prevalence, extent and severity of poor oral health-related quality of life was so high among the study population compared with national-level estimates, especially as evidence from the literature suggests that poor oral health-related quality of life – as assessed by OHIP-14 – is associated with untreated dental needs9 and is recognized as deteriorating over the lifecourse.10 The findings warrant further investigation at a more representative level.
The risk indicators for poor oral health-related quality of life in our study were perhaps unsurprising. Social determinants have long been associated with poor oral health-related quality of life, both among non-representative marginalized populations such as homeless populations in Hong Kong,9 and national-level surveys conducted in Australia, the United Kingdom, Sweden and Germany.11 That the more socially impoverished in our study – as indicated by ownership of a means-tested Government healthcare card – had poorer oral health-related quality of life supports the notion of socio-economic inequality being associated with greater disease prevalence and health-related quality of life in general.12
The literature is replete with examples of dentate status factors, such as multiple missing teeth, impacting negatively on oral health-related quality of life. For example, Pallegedara and Ekanayake reported that, among older individuals in Sri Lanka, oral health-related quality of life was significantly affected by tooth loss,13 and Lawrence and colleagues reported that having ‘one or more missing teeth’ by the age of 32 years was a risk indicator for reporting one or more OHIP-14 items ‘fairly often’ or ‘very often’.14 Dental service utilization patterns such as last visiting a dentist because of a problem, have also been associated with poor oral health-related quality of life, with this association often being used to determine construct validity of new derivations of the Oral Health Impact Profile.15
Financial factors such as delaying dental care because of cost and having difficulty paying a $100 dental bill were risk indicators for poor oral health-related quality of life. This supports the findings of Chavers and colleagues, who reported that one of the strongest predictors of poor oral health-related quality of life in their study was difficulty in paying an unexpected $500 dental bill.16 The prevalence of participants reporting difficulty paying a $100 dental bill in the current study was five times that of national-level estimates,6 indicating that for this specific Indigenous population, financial costs are a substantial barrier to receipt of timely dental care. Indigenous adults in Port Augusta who hold a healthcare card (government benefits card) are able to access free emergency dental services through an Indigenous-controlled health service (dentist available one day per week), through one local private practice participating in a specific Aboriginal Dental Scheme, or reduced cost care though the regular adult public dental service (the South Australian Dental Service). Routine dental care can be accessed through the same services, with waiting lists varying from approximately 10–18 months. There are limited resources for general care provision through the Indigenous-controlled health service. For those not entitled to a healthcare card (in this study, 24.4%), dental service provision is only available through the private sector. There are currently three private practices in Port Augusta, serving a population of approximately 13 000.1
It was unsurprising that non-ownership of a toothbrush was a risk indicator for poor oral health-related quality of life, given evidence that irregular toothbrushing is associated with increased levels periodontal disease,17 which is known to impact negatively on perceived life quality.14 Non-ownership of a toothbrush is problematic among many Indigenous Australian populations, and may be linked in part to constant movement between households in a given location to: (1) other households in a given location; (2) households in more remotely-located outstations or homelands; or (3) urban centres. Chronic household over-crowding is an acknowledged problem among many Indigenous Australians,18 which additionally predisposes to non-ownership (or frequent misplacement) of toothbrushes.19
Each of the risk indicators for poor oral health-related quality of life in our study are amenable to change. Ways in which these factors might be mitigated include: (1) socio-economic factors: addressing upstream factors that influence important social determinants in the Aboriginal context including crowded households and car ownership; (2) dental service utilization factors: making dental services for Aboriginal clients more accessible and user-friendly, including increasing the number of Aboriginal dental service providers and ensuring oral health services are included, and appropriately funded for, in the primary health care models of Aboriginal Health Services; (3) financial factors: recognizing that, for many Aboriginal clients, dental care is simply not affordable. Explore avenues of providing more financially-accessible dental care services, including increasing the remit of oral health therapists and other dental auxiliaries20,21 and; (4) dental self-care factors: increasing the availability and affordability of toothbrushes and fluoridated toothpaste.