Australian Dental Journal
The official journal of the Australian Dental Association
DATA WATCH
Australian Dental Journal 2014; 59: 395–400 doi: 10.1111/adj.12205
Oral health of Australian Indigenous children compared to non-Indigenous children enrolled in school dental services* Australian Research Centre for Population Oral Health, The University of Adelaide, South Australia. INTRODUCTION The oral health of children is important as dental caries often starts early in life and is considered predictive of later disease experience.1 In addition to the dental consequences that can include early tooth loss and malocclusion, children with high levels of decay experience have been associated with higher rates of behavioural problems, affecting their families, schooling and self-esteem.2–4 There has been a marked improvement in the oral health of children in the general Australian population in the last decade.5 However, there are still groups of children who experience higher levels of dental caries such as children who live in remote areas which are populated with Indigenous communities.6 Dental caries is a widespread disease within Indigenous communities and it has a particularly severe impact on children. Indigenous children are recognized as having, on average, twice as much decay experience as other Australian children.7 In some communities, levels of decay for Indigenous children are even up to five times higher than that of non-Indigenous children.8–10 Although there are a number of studies reporting Indigenous children’s oral health status, there is a need to update this information with recent data. The aim of this article is to report the oral health status of Indigenous children attending a school dental service during 2010. More importantly, this article will compare dental caries experience between Indigenous and non-Indigenous children by state and territory. METHODOLOGY Data were obtained on children aged 5–15 years who received an examination with the school dental service (SDS) in the 2010 calendar year. Data for Queensland, South Australia, Western Australia, Tasmania, the Northern Territory and the Australian Capital Territory were sourced from the Child Dental Health Survey (CDHS). The CDHS is an annual surveillance *This article is a solicited opinion piece and did not undergo peer review. © 2014 Australian Dental Association
survey that monitors the dental health of children enrolled in school and community dental services operated by the health departments or authorities of Australia’s six state and two territory governments. New South Wales was not included in the data collection as the sample was not representative. Estimates for Australia (overall estimates) in this report also exclude Victoria due to lack of access to the 2010 data. Children were sampled at random from SDS clinics by selecting those examined during the 2010 calendar year who were born on specific days of the month. The application of diagnostic criteria employed in this data collection was based on the clinical judgement of the examining dental therapist or dentist. Detailed instructions were provided to clinics to explain the collection of clinical data, but there were no formal sessions of instruction in diagnosis undertaken for the purpose of the survey, and no repeat examinations for the purpose of assessing inter- or intra-examiner reliability. The examiner also recorded demographic characteristics of each sampled child including age and gender. Indigenous status of children is collected in daily practice in every state and territory SDS. Children, or parents of younger children, are asked to report if they are Indigenous. More detail is collected in some states with categories defined as ‘Non-Aboriginal’, ‘Aboriginal’, ‘Torres Strait Islander’, ‘Aboriginal and Torres Strait Islander’, ‘South Sea Islander’ or ‘Unknown’. In this report, ‘Aboriginal’, ‘Torres Strait Islander’, ‘Aboriginal and Torres Strait Islander’ or ‘South Sea Islander’ responses are grouped together and referred to as ‘Indigenous’. Those children with an unknown Indigenous status (3.9%) were excluded from the results. The methodology used for diagnosis and reporting of caries experience follows those published by the World Health Organization11 for oral epidemiological studies. The severity of caries experience was measured by the mean count of clinically detectable decayed, missing and filled teeth. Deciduous decay experience (referred to as dmft) is defined as the number of deciduous teeth that are untreated decayed (d), missing due to decay (m), and filled due to decay (f). For children aged 5–10, dmft only is calculated as the majority of 395
ARCPOH non-Indigenous children in this age group. Differences by Indigenous status were largest among children aged 5–7, where Indigenous children had approximately 1.5 more teeth with untreated decay than nonIndigenous children.
deciduous teeth that have been replaced by permanent teeth by the age of 11. Permanent decay experience (referred to as DMFT) is defined as the number of permanent teeth that are untreated decayed (D), missing due to decay (M), and filled due to decay (F) and is calculated for children aged 6–15. Unmet need is defined as the number of teeth with untreated decay (d or D). The prevalence of caries experience was measured by the percentage of children with dmft>0 for deciduous teeth or DMFT>0 for permanent teeth. Data sourced from the 2010 CDHS were weighted at the regional level to account for the different sampling fractions implemented to select children in the survey in each state and territory. Regions were based on the 2006 Australian Standard Geographical Classification and were defined at the Statistical Subdivision level for capital cities and Statistical Division level for rest of state regions. Data were also weighted to adjust for the different recall intervals children experience at SDS clinics as children on shorter recall intervals had a higher chance of selection in the survey.
Severity of caries experience in deciduous dentition Indigenous children aged 5–10 had 0.1 to 0.6 missing teeth due to caries. They had consistently more teeth missing due to decay than non-Indigenous (N-Ind) counterparts. Differences by Indigenous status were largest for children aged 6–7 where Indigenous children had twice as many teeth missing due to caries as non-Indigenous children. The number of deciduous teeth filled due to caries ranged from 0.5 to 1.6 teeth among 5–10 year olds. It was also consistently higher for Indigenous children. Differences by Indigenous status were largest for children aged 7 and were statistically significant for age groups 5–7. Indigenous children aged 7–8 had the highest number of filled deciduous teeth with approximately 1.5 teeth filled due to decay. Indigenous children aged 5–10 had an average dmft from 2.2 to 4.9. Indigenous children’s dmft was consistently higher than that among non-Indigenous children, particularly among the younger age groups. Indigenous children aged 5–7 had almost twice the decay experience of non-Indigenous children in that age group. Differences in the severity of decay experience by Indigenous status were statistically significant for all age groups (Fig. 1).
RESULTS The 2010 CDHS examined 103 387 children aged 5–15 years across six states and territories. Among those surveyed, 89.3% of children were non-Indigenous, 6.8% were Indigenous and 3.9% of children did not state their Indigenous status. Caries experience in deciduous dentition Unmet need
Prevalence of caries experience in deciduous dentition
Indigenous children aged 5 had the highest level of untreated decay with an average of 3.4 deciduous teeth untreated (Fig. 1). Indigenous children aged 5–9 had significantly more untreated decay than
Missing (m)
Decayed (d)
6
The prevalence of caries experience among 5–10 year old Indigenous children ranged from 66.3% to Filled (f)
4.85 4.17
5
4.27 3.84
3.66
Number
4 3
2.51
2.37
2.07
2.21
2.29
2.32
1.74
2
5 6 N-Ind: non-Indigenous Ind: Indigenous
7
8
9
Ind
N-Ind
Ind
N-Ind
Ind
N-Ind
Ind
N-Ind
Ind
N-Ind
Ind
0
N-Ind
1
10
Age (years)
Fig. 1 Mean number of decayed, missing and filled deciduous teeth. 396
© 2014 Australian Dental Association
Oral health of Australian Indigenous children approximately twice the level of untreated decay as their non-Indigenous counterparts. At 15 years, Indigenous children had an average of 2.43 permanent teeth with untreated decay compared with 1.30 teeth for non-Indigenous children (Fig. 3).
81.9%. Overall, the proportion of children with decay experience in their deciduous dentition was consistently higher for Indigenous children than for nonIndigenous children. Differences in prevalence by Indigenous status were particularly evident among children aged 5–7. Nearly 73% of Indigenous children aged 5 had decay experience in their deciduous teeth compared with 44.8% of non-Indigenous children. At 7 years of age, 81.9% of Indigenous children had decay experience compared with 55.1% of nonIndigenous children (Fig. 2).
Severity of caries experience in permanent dentition Estimates of the number of permanent teeth missing due to decay for 6–12 year old Indigenous children ranged from 0 to 0.2. Indigenous (Ind) children had more teeth missing due to decay than non-Indigenous (N-Ind) children in all age groups, although differences by Indigenous status were generally not statistically significant. The number of permanent filled teeth increased steadily across age for both Indigenous and nonIndigenous children. The average number of filled teeth was consistently higher among Indigenous children than non-Indigenous children. Differences by Indigenous status were more evident among children aged 13–15; however, no statistically significant
Caries experience in permanent dentition Unmet need At 6 years of age, Indigenous children had a similar level of untreated decay as non-Indigenous children. However, as children aged the gap in the level of untreated decay by Indigenous status significantly widened. Indigenous children aged 13–15 years had
Indigenous
Non-Indigenous
100 90
80.6
81.9
75.9
80
66.3
70 Per cent
78.1
72.7
61.4
60.5
60
55.1
53.0
50
53.9
44.8
40 30 20 10 0 5
6
7
8
9
10
Age (years) Fig. 2 Percentage of children with dmft>0. 6 Decayed (D)
Missing (M)
Filled (F)
4.07
4.05 5 3.31
2.49
3 1.72
1.75 2
1.29
6
7
8
N-Ind: non-Indigenous Ind: Indigenous
9
10
11
12
13
14
Ind
N-Ind
Ind
N-Ind
Ind
N-Ind
Ind
N-Ind
Ind
Ind
N-Ind
Ind
N-Ind
Ind
N-Ind
N-Ind
Ind
N-Ind
0.88
0.68
0.61
0.41
0.24
0.12 0
0.55
0.17
Ind
1
2.22 1.59
1.30
1.13 0.76
N-Ind
Number
4
15
Age (years)
Fig. 3 Mean number of decayed, missing and filled permanent teeth. © 2014 Australian Dental Association
397
ARCPOH 100 Non-Indigenous
Indigenous
83.6
81.0
90 70.1
80
52.4 57.6
Per cent
70 49.8
60
51.4
44.0
34.6
36.9
30.4
40
28.7
30
31.7
20.7
20
0
64.8
46.8
50
10
61.8
9.7
13.2
6.7
6
7
8
9
10 11 Age (years)
12
13
14
15
Fig. 4 Percentage of children with DMFT>0.
pared with 20.7% of non-Indigenous children. At 15 years of age, 81% of Indigenous children had decay experience compared with 64.5% of non-Indigenous children. The difference in decay experience between Indigenous and non-Indigenous children ranged from 1.2 times (aged 12) to 1.7 times (aged 9).
differences were found between Indigenous and nonIndigenous children. Mean DMFT was consistently higher for Indigenous children than non-Indigenous children aged 6–15. The gap in decay experience between Indigenous and nonIndigenous children was statistically significant in most age groups, and was particularly evident for children aged 13–15. Mean DMFT for Indigenous children aged 15 was 4.07 compared with 2.49 for non-Indigenous children (Fig. 3).
Dental decay by Indigenous status and by state and territory The total decay experience in the deciduous teeth (dmft) of children aged 5–6 by Indigenous status and state or territory is presented in Table 1. The level of caries experience in deciduous teeth was consistently higher for Indigenous children in each state and territory in both severity and prevalence. Indigenous children in the Northern Territory had a three-fold higher caries severity score than non-Indigenous children, and in Western Australia and South Australia the magnitude was two-fold. Total decay experience was
Prevalence of caries experience in permanent dentition The prevalence of caries experience in permanent teeth among 6–15 year old Indigenous children ranged from 9.7% to 83.6%. Prevalence was consistently higher for Indigenous children than non-Indigenous children. Nearly 35% of Indigenous children aged 8 had decay experience in their permanent teeth com-
Table 1. Dental decay in the deciduous teeth of children aged 5–6 by Indigenous status and by state and territory, 2010 State/territory
Non-Indigenous Severity
Qld*¥ WA*¥ SA*¥ Tas*¥ ACT NT*¥ Australia (six states/territories)*¥
Indigenous Prevalence
Severity
Prevalence
Mean dmft
95% CI
%
95% CI
Mean dmft
95% CI
%
95% CI
3.11 1.14 2.01 2.08 0.96 1.72 2.22
2.96–3.26 0.91–1.36 1.93–2.09 1.98–2.19 0.86–1.07 1.51–1.92 2.13–2.32
59.3 36.2 46.7 51.5 28.0 39.9 48.9
57.3–61.2 30.9–41.8 45.5–47.9 49.7–53.2 25.7–30.5 36.6–43.3 47.2–50.5
4.21 3.01 4.28 2.79 n.p. 5.31 4.22
3.71–4.70 1.94–4.08 3.77–4.80 2.20–3.39 n.p. 4.94–5.69 3.88–4.55
73.3 69.2 72.7 65.6 n.p. 84.0 74.4
67.5–78.4 51.8–82.5 67.3–77.6 55.5–74.4 n.p. 80.7–86.8 70.4–78.0
*Significant difference in mean dmft. ¥ Significant difference in prevalence of dmft. n.p. The Indigenous sample size is too small to publish reliable estimates. 398
© 2014 Australian Dental Association
Oral health of Australian Indigenous children highest for Indigenous children in the Northern Territory (5.31), South Australia (4.28) and Queensland (4.21) (Table 1). Indigenous children in the Northern Territory and Western Australia were approximately twice as likely as their non-Indigenous counterparts to have at least one tooth with caries experience in their deciduous teeth. Differences in prevalence by Indigenous status were statistically significant in all states and territories (Table 1). The total decay experience in the permanent teeth (DMFT) of children aged 12–13 by Indigenous status and state or territory is presented in Table 2. Indigenous children had consistently higher levels of decay experience in their permanent teeth than non-Indigenous children in each state and territory. In particular, Indigenous children from the Northern Territory had 1.8 times more decay experience than their non-Indigenous counterparts. Differences in mean DMFT by Indigenous status were statistically significant in the Northern Territory and South Australia. Mean DMFT was highest for Indigenous children in the Northern Territory and Queensland with more than three permanent teeth affected by decay experience. The prevalence of decay experience in permanent teeth was also consistently higher among Indigenous children than non-Indigenous children in each state and territory. Differences in prevalence by Indigenous status were statistically significant in the Northern Territory (75.1% compared with 58.8%) and South Australia (57.1% compared with 44.7%).
More importantly, these data indicate that children from an Indigenous background are more likely to experience caries in both their deciduous and permanent dentition, and have higher levels of untreated decay than their non-Indigenous counterparts. This study confirms that unmet need, caries prevalence and severity of caries experience among Australian Indigenous children attending the SDS, were consistently higher than that of non-Indigenous children for all ages, type of dentition and location. Our findings also confirm that substantial oral health inequalities exist between Indigenous and nonIndigenous child populations in Australia. A number of factors have been identified to explain the reason for the inequalities such as social isolation, culturally inappropriate oral health service provision, remote location, no access to fluoride, and exposure to westernized diet. These risk factors have been tackled in several ways such as the introduction of fluoride varnish applications12 and targeted health promotion at the individual, family and community level. However, results from this study show that oral health inequalities still exist between Indigenous and non-Indigenous children despite some effort being put into preventing dental caries in the Indigenous population. The results of this study also confirm that a higher prevalence and most severe caries had been found in deciduous dentition among younger Indigenous children. Deciduous teeth have thinner enamel, therefore caries progression is faster than in permanent teeth. Oral hygiene practices may be more difficult to establish in younger children being dependent on others such as parents or caregivers for their oral hygiene needs and healthy behaviour development. A limitation of this study is that it included only children who enrolled in the SDS and the sample size of Indigenous children was small and not nationally representative. In all jurisdictions, children from both public and private schools are eligible for dental care through an SDS. The care typically provided in an SDS
DISCUSSION Despite significant improvements in oral health among children over the last three decades,5 the data presented in this report indicate that dental caries remains a common childhood condition in Australia; a large number of children are affected to some degree by the time they reach the end of their childhood.
Table 2. Dental decay in the permanent teeth of children aged 12–13 by Indigenous status and by state and territory, 2010 State/territory
Non-Indigenous Severity
Qld WA SA*¥ Tas ACT NT*¥ Australia (six states/territories)*
Indigenous Prevalence
Severity
Prevalence
Mean DMFT
95% CI
%
95% CI
Mean DMFT
95% CI
%
95% CI
2.14 0.72 1.02 1.30 0.74 1.86 1.45
1.94–2.33 0.52–0.92 0.98–1.06 1.23–1.38 0.66–0.82 1.59–2.13 1.34–1.55
60.1 35.4 44.7 50.6 36.2 58.8 49.2
57.1–63.0 28.5–43.0 43.4–46.0 48.7–52.6 32.9–39.6 53.0–64.3 46.8–51.5
3.03 n.p. 1.73 1.51 n.p. 3.37 2.42
2.17–3.89 n.p. 1.38–2.09 1.06–1.95 n.p. 3.00–3.74 1.76–3.09
70.3 n.p. 57.1 58.7 n.p. 75.1 60.2
57.4–80.6 n.p. 50.9–63.2 45.5–70.7 n.p. 70.4–79.3 45.6–73.2
*Significant difference in mean DMFT. Significant difference in prevalence of DMFT. n.p. The Indigenous sample size is too small to publish reliable estimates. ¥
© 2014 Australian Dental Association
399
ARCPOH includes dental examinations, preventive services and restorative treatment. However, there are some variations among state and territory programmes with respect to priority age groups and the nature of services. In some jurisdictions, caries risk assessment was used to determine recall interval and preventive treatment. Consequently, there were variations in the extent of enrolments in SDSs, with some jurisdictions serving nearly 80% of primary school children and others serving smaller proportions. Therefore, any comparisons between states/territories should be made with caution. These findings highlight the need for results from a well-planned epidemiological study which could provide more reliable and valid statistics. A well-planned epidemiological study would help generate findings that would be generalizable nationally. These findings also indicate the need for a trend analysis in inequality in oral health between Indigenous and non-Indigenous groups. Oral health inequality is a complex issue affected by the interaction of many factors. In order to achieve an effective intervention, it needs to be based on good evidence, be culturally appropriate, and focused more on upstream influences. ACKNOWLEDGEMENTS This article used data from the Child Dental Health Survey which was funded by the Australian Institute of Health and Welfare. We wish to acknowledge the time and effort contributed by the state and territory health authorities in the collection and provision of the data used in this report, along with the continued cooperation of individual dentists and dental therapists. This article was prepared by Diep Ha.
REFERENCES 1. Li Y, Wang W. Predicting caries in permanent teeth from caries in primary teeth: an eight-year cohort study. J Dent Res 2002; 81:561–566.
400
2. Gao XL, Hsu CY, Xu YC, Loh T, Koh D, Hwarng HB. Behavioral pathways explaining oral health disparity in children. J Dent Res 2010;89:985–990. 3. Williamson R, Oueis H, Casamassimo PS, Thikkurissy S. Association between early childhood caries and behavior as measured by the child behavior checklist. Pediatr Dent 2008;30:505–509. 4. Bonetti D, Johnston M, Clarkson JE, et al. Applying psychological theories to evidence-based clinical practice: identifying factors predictive of placing preventive fissure sealants. Implement Sci 2010;5:25. 5. Mejia GC, Ha DA. Dental caries trends in Australian school children. Aust Dent J 2011;56:227–230. 6. Ha D, Amarasena N, Crocombe L. The dental health of Australia’s children by remoteness: Child Dental Health Survey Australia 2009. Cat. no. DEN 225. DSR Series 63. Canberra: AIHW, 2013. 7. Jamieson LM, Armfield JM, Roberts-Thomson KF. Oral health of Aboriginal and Torres Strait Islander children. Australian Institute of Health and Welfare. Cat. no. DEN 167. Canberra: AIHW, 2007. 8. Schamschula RG, Cooper MH, Adkins BL, Barmes DE, Agus HM. Oral conditions in Australian children of Aboriginal and Caucasian descent. Community Dent Oral Epidemiol 1980;8:365–369. 9. Endean C, Roberts-Thomson K, Wooley S. Anangu oral health: the status of the Indigenous population of the Anangu Pitjantjatjara lands. Aust J Rural Health 2004;12:99–103. 10. Jamieson LM, Armfield JM, Roberts-Thomson KF. Indigenous and non-Indigenous child oral health in three Australian states and territories. Ethn Health 2007;12:89–107. 11. World Health Organization. Oral health survey basic methods. Geneva: WHO, 1998. 12. Slade GD, Bailie RS, Roberts-Thomson K, et al. Effect of health promotion and fluoride varnish on dental caries among Australian Aboriginal children: results from a community-randomized controlled trial. Community Dent Oral Epidemiol 2011;39: 29–43.
Address for correspondence: Diep H Ha Australian Research Centre for Population Oral Health School of Dentistry The University of Adelaide Adelaide SA 5005 Email:
[email protected] © 2014 Australian Dental Association