King et al.

BMC Public Health (2023) 23:1446 BMC Public Health

https://doi.org/10.1186/s12889-023-16381-5

RESEARCH Open Access

Oral health literacy, knowledge

and perceptions in a socially and culturally
diverse population: a mixed methods study
Shalinie King1*, Ayesha Thaliph2, Liliana Laranjo2, Ben J. Smith3 and Joerg Eberhard4

Abstract
Background Poor oral health literacy has been proposed as a causal factor in disparities in oral health outcomes. This
study aims to investigate oral health literacy (OHL) in a socially and culturally diverse population of Australian adults
visiting a public dental clinic in Western Sydney.
Methods A mixed methods study where oral health literacy was assessed using the Health Literacy in Dentistry
scale (HeLD-14) questionnaire and semi-structured interviews explored oral health related knowledge, perceptions
and attitudes. Interviews were analysed using a thematic approach.
Results A sample of 48 participants attending a public dental clinic in Western Sydney was recruited, with a mean
age of 59.9 (SD16.2) years, 48% female, 50% born in Australia, 45% with high school or lower education, and 56%
with low-medium OHL. A subgroup of 21 participants with a mean age of 68.1 (SD14.6) years, 40% female, 64% born
in Australia, 56% with a high school or lower education, and 45% with low-medium OHL completed the interview.
Three themes identified from the interviews included 1) attitudes and perceptions about oral health that highlighted
a lack of agency and low prioritisation of oral health, 2) limited knowledge and education about the causes and con-
sequences of poor oral health, including limited access to oral health education and finally 3) barriers and enablers
to maintaining good oral health, with financial barriers being the main contributor to low OHL.
Conclusions Strategies aimed at redressing disparities in oral health status should include improving access to oral
health information. The focus should be on the impact poor oral health has on general health with clear messages
about prevention and treatment options in order to empower individuals to better manage their oral health.
Keywords Oral health literacy, Oral health knowledge, Oral health disparities, Held-14, Poor oral health, Oral health

Background
*Correspondence: The World Health Organisation (WHO) identifies oral
Shalinie King
shalinie.king@sydney.edu.au health as a key indicator of overall health, well-being
1
Westmead Applied Research Centre and the Sydney Dental School, and quality of life [1]. Poor oral health due to oral dis-
Faculty of Medicine and Health, The University of Sydney, Sydney, ease can result in toothache, fair/poor self-rated oral
Australia
2
Westmead Applied Research Centre, Faculty of Medicine and Health, health, discomfort with appearance and food avoidance
The University of Sydney, Sydney, Australia [2]. The WHO reports that the burden of oral disease is
3
Sydney School of Public Health, and the Westmead Applied Research highest in socioeconomically disadvantaged groups and
Centre, Faculty of Medicine and Health, The University of Sydney, Sydney,
Australia is projected to increase due to the growing consump-
4
Sydney Dental School and the Charles Perkins Centre, Faculty tion of sugar and tobacco use, particularly in devel-
of Medicine and Health, The University of Sydney, Sydney, Australia oping countries [3]. Likewise in Australia, those with

© The Author(s) 2023. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which
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King et al. BMC Public Health (2023) 23:1446 Page 2 of 10

a lower socio-economic status (SES) are dispropor- Methods

tionately affected by poor oral health, the incidence of Study design
which has been on an upward trajectory since 2004 [4]. The study has a mixed methods design, with oral health
Untreated, oral disease including tooth decay and literacy assessed using the short form Health Literacy in
periodontitis (gum) disease can lead to tooth loss. A Dentistry scale (HeLD-14) [18] and insights on aspects
dentition consisting of fewer than 21 teeth, is consid- of oral health knowledge, attitudes and perceptions gath-
ered non-functional [5] and results in compromised ered using semi-structured interviews. The study was
chewing ability which in turn can lead to low body approved by the Western Sydney Local Health District
mass index (BMI) and undernutrition [6]. There is also Human Research Ethics Committee (protocol number:
now substantial evidence indicating that periodonti- 2021/ETH12053).
tis increases the risk for cardiovascular disease (CVD)
[7], and hypertension [8] and has a bi-directional rela- Participants and recruitment
tionship with diabetes [9]. Poor oral health also has an Participants were adults over the age of 35 who were
economic cost. In 2015 world-wide costs due to dental receiving dental treatment at the Westmead Centre
disease were reported to be $544 billion, ranking third for Oral Health (WCOH). The WCOH is a public den-
behind diabetes and CVD [10]. In Australia, 61% of the tal clinic that also provides clinical training facilities for
cost of dental care falls to the individual, 25% of the dental students and serves individuals who have a low
cost is covered by the government, and 14% by health income. The participants were part of a larger study
insurance funds [11]. investigating perceptions of oral health related mobile
Oral health literacy (OHL) is defined as the “degree phone applications, therefore the inclusion crite-
to which individuals have the capacity to obtain, pro- ria included adults ≥ 30 years, possession of a smart
cess and understand basic oral health information and phone and willingness to have an oral health applica-
services needed to make appropriate health decisions” tion installed on their phone. The exclusion criteria were
[12]. Poor OHL has been proposed as a contributing not being able to read and understand English and hav-
factor in disparities in oral health outcomes [13] and as ing cognitive impairment. Participants were recruited
such has been shown to be associated with increased on site using convenience sampling at the WCOH from
negative oral health impacts including dental emergen- March 2022-September 2022 at the WCOH by a research
cies, an increase in dental decay and poor periodontal assistant who attended the clinic on selected days. Par-
health [14, 15]. Therefore, improving OHL is recog- ticipants who completed the OHL survey and elected to
nised as an important priority for promoting better oral undertake the semi-structured interviews were included
health outcomes, particularly among those experienc- in a sub-sample which comprised a range of participants
ing social disadvantage. in terms of age, gender and culturally and linguistically
Western Sydney is an area in NSW, Australia which diverse backgrounds.
has a population with a highly diverse social and cul-
tural profile and a relatively high proportion of persons Data collection
in the bottom quintiles of socioeconomic status (SES) The survey completed by study participants measured
[16]. Previous research on OHL in this region has found OHL using the HeLD-14 questionnaire [18] which was
that patients with CVD have poor knowledge about developed to estimate the capacity of an individual to
oral health and receive little information relating to oral obtain, process or interpret, and understand basic oral
health from cardiac health staff [17]. These findings sug- health information and services needed to make appro-
gest that there is a need for better integration of oral priate oral health-related decisions [18]. The instrument
health into chronic disease management programmes reflects the multi-dimensional nature of OHL and con-
such as cardiac rehabilitation. Currently, there is a lack of tains 7 domains and 14 questions. The survey was admin-
coordinated oral health literacy programmes for priority istered by tablet using an online form hosted through
population subgroups in Western Sydney and very lim- the research electronic data capture (REDCap) plat-
ited integration of oral health information into broader form. Each of the 14 HeLD questions was scored using a
chronic disease management. 5-point Likert scale ranging from 0 (“Unable to do”) to 4
This study aims to investigate OHL among adults from (“without any difficulty”) and summed to obtain an over-
disadvantaged population segments in Western Sydney all score. The possible range of HeLD-14 scores is from
in order to inform the design and development of strate- 0 (lowest oral health literacy) to 56 (highest oral health
gies to improve oral health literacy and contribute to pol- literacy). Additional questions about participant charac-
icy and programmes to reduce disparities in oral health teristics included age, gender, country of birth, education
status. level, number of teeth and frequency of tooth brushing.
King et al. BMC Public Health (2023) 23:1446 Page 3 of 10

For the semi-structured interviews, a guide (Addi- Table 1 Participant characteristics in the survey group and
tional file 1) was developed based on a previous study interview sub-group
that explored oral health knowledge in pregnant Aus- Enrolled: 51, withdrew: 3
tralian women [19]. Broad topics covered in the inter-
Total participants – HeLD-4 Questionnaire: 48, OHL interview: 21
view included perceptions of current oral health status,
importance of oral health compared to overall health, Survey OHL interview
consequences of poor oral health, knowledge and use of Age 60 (16.11) 68 (14.59)
preventive measures, and barriers and enablers to achiev- Female, n (%) 23 (48%) 9 (43%)
ing good oral health. The interviews were conducted one- Australian born, n (%) 24 (50%) 14 (66%)
on-one by telephone, with an average duration of 30 min
Educational attainment
(ranging from 15–60 min). All the interviews were con-
College or University 17 (35%) 5 (24%)
ducted by the same research assistant (AT) who had expe-
Technical college (TAFE) 9 (19%) 4 (19%)
rience in qualitative research and were continued until
Secondary school 18 (38%) 9 (43%)
data saturation appeared to have been reached. These
Primary school 4 (8%) 3 (14%)
were audio recorded and field notes were taken during the
Number of Teeth
interview. Participants did not receive any incentives for
1–9 teeth 5 (11%) 4 (19%)
completing the interviews. They were not able to review or
10–19 teeth 17 (35%) 11 (52%)
edit their responses, however they were free to withdraw
  ≥ 20 teeth 25 (52%) 5 (24%)
from the study at any point.
Did not specify 1 (2%) 1 (5%)
Brushing frequency
Data analysis Twice a day 29 (60%) 13 (62%)
Descriptive characteristics were analysed by calculating Once a day 17 (35%) 6 (29%)
absolute values (n) and percentages (%). HeLD-14 scores Less than once a day 2 (5%) 2 (9%)
were categorised into tertiles: ≤ 35 (low OHL), 36–46 OHL Score
(medium OHL) and > 46 (high OHL).   ≤ 35 (Low) 4 (8%) 2 (9%)
Audio recordings of interviews were transcribed, and 35–46 (Medium) 23 (48%) 8 (36%)
the data imported and managed within NVivo 12 [20].   > 46 (High) 20 (42%) 12 (55%)
Thematic analysis was conducted following the six stages
proposed by Braun and Clarke [21] which included
familiarisation with the data, generation of initial codes, 50% were born in Australia and the remaining were
searching for themes, reviewing themes and sub-themes, represented by 16 different countries and 11 different
and defining and naming themes and sub-themes [21]. languages. A college or university level education was
A sample of transcripts were independently coded by attained by 35%, technical level education (TAFE) by
(SK) and (AT) and the codes grouped into preliminary 19%, secondary school level by 37% and primary school
themes and sub-themes. These transcripts and themes level education by 8% of the survey group. The mean age
were reviewed by an experienced qualitative researcher of interview participants was 68.1 (SD14.6) years; 43%
(LL). Following this review the remaining transcripts were female and 66% were born in Australia (Table 1).
were coded by (SK) and (AT). Final codes and themes A college or university level education was attained by
were reviewed by co-authors to ensure that the themes 24%, TAFE level education by 19%, secondary school
accurately reflected the interview data. Any points of dis- level by 42% and primary school level education by 14%.
agreement regarding coding or thematic grouping were Most participants brushed twice a day in both the survey
discussed with co-authors in order to reach consensus. group and interview subgroup (59%, 62% respectively).
This component of the study follows the “Consolidated The number of participants with a non -functional denti-
criteria for reporting qualitative research” (COREQ) tion (fewer than 20 teeth) was 46% in the survey group
checklist for reporting qualitative research [22]. and 71% in the interview subgroup. The OHL scores were
low-medium in 56% of the survey group, and 42% in the
Results interview group. In the interview subgroup, the majority
A total of 51 people were recruited, 3 participants with- of participants self-reported their oral health as poor.
drew and were excluded from the analytic sample. The
HeLD-14 questionnaire was completed by 48 partici- Scores in domains of oral health literacy
pants, a subgroup of 21 participants completed the inter- As shown in Table 2, the major contributing factor to
view. The mean participant age for the survey group low OHL included economic barriers which received
was 59.9 (SD 16.12) years, 48% were female (Table 1),
King et al. BMC Public Health (2023) 23:1446 Page 4 of 10

Table 2 Participant scores for individual questions on the HeLD -14 questionnaire
Question Domain Score

Ability to pay attention to your dental or oral health Receptivity 2.60

Ability to make time for things that are good for your dental or oral health? Receptivity 3.35
Ability to read written information, for example, leaflets given to you by your dentist? Understanding 3.56
Ability to read dental or oral health information brochures left in dental clinics and waiting rooms? Understanding 3.49
Ability to take family or a friend with you to a dental appointment? Utilisation 2.88
Ability to ask someone to go with you to a dental appointment? Utilisation 2.96
Ability to pay to see a dentist? Economic barriers 1.48
Ability to pay for medication to manage your dental or oral health? Economic barriers 2.52
Ability to get a dentist appointment? Access 3.79
Do you know what to do to get a dentist appointment? Access 3.72
Ability to look for a second opinion about your dental health from a dental health professional? Communication 2.33
Ability to use information from a dentist to make decisions about your dental health? Communication 3.56
Ability to carry out instructions that a dentist gives you? Utilisation 3.60
Ability to use advice from a dentist to make decisions about your dental health? Utilisation 3.67
Scores (0 = unable, 1 = Very difficult to perform, 2 = Neutral, 3 = With a little difficulty, 4 = Without any difficulty

a score below 2 (indicating that most were unable or that oral health declined with age (Table 4, quote 1) or a
found it very difficult to pay to see a dentist, or to pay sense of resignation about their poor oral health status
for medication to manage their oral health). Other fac- in terms that nothing would prevent further deteriora-
tors that included scores below 3 (indicating that par- tion or that they just wanted the teeth removed (Table 4,
ticipants were unable to, found it very difficult or had quotes 2–3). Additionally, although many participants
some difficulty performing tasks) included obtaining believed that they had poor oral health (Table 4, quote
a second opinion about their dental health (2.33), the 4), most only prioritised oral health care when problems
ability to pay for medication to manage their oral health developed (Table 4, quote 5). Furthermore, a common
(2.52), the ability to pay attention to their oral health reflection was that they were often not motivated to
(2.60), and obtain support from family or friends for
dental visits (2.88 and 2.96 respectively). Table 3 Major themes and subthemes concerning oral health
THEME SUB THEMES
Factors contributing to oral health literacy
Attitudes and perceptions ▪ Lack of agency/control over oral health
The major themes identified from qualitative analysis about oral health ▪ Low prioritisation of oral health
of the interviews included attitudes and perceptions
▪ Misconceptions about preventive oral
about oral health care, limited knowledge and education health practices
about oral health and barriers and enablers to manag- Limited knowledge and educa- ▪ Limited knowledge about the conse-
ing oral health. These 3 themes were expanded into sub- tion about oral health quences of poor oral health
themes, as is presented in Table 3, and their relevance to ▪ Limited knowledge about the causes
the seven domains of OHL assessed by the HeLD-14 is of poor oral health
▪ Limited access to oral health education
examined below.
Barriers and enablers to man- ▪ Barriers:
aging oral health - Economic barriers
Receptivity
- Fear of dental treatment
The scores for the domain of receptivity included 2.60
- Long waiting lists for dental care
for the participants ability to pay attention to their oral
- Limited access to transport
health and 3.35 for the ability to make time to look after
- Poor delivery of oral health information
their oral health (Table 3).
▪ Enablers:
The interview data suggests that the reason many par-
- Better information about available oral
ticipants were unable to or found it very difficult to pay health services and
attention to their oral health may be explained by their - Better delivery of oral health information
attitudes and perceptions about oral health. Several par- - Access to universal dental records
ticipants reported that they lacked agency over their - Access to regular check-ups
oral health. This was reflected in either the expectation - More timely oral health advice
King et al. BMC Public Health (2023) 23:1446 Page 5 of 10

Table 4 Attitudes and perceptions about oral health

Lack of agency/control over oral health

1. I know some people maintain good standard of teeth through to old age but I think quite a few of them have had – even younger than me –
replacements and dentures (…..) I’m nearly seventy so, it would be unsurprising that my teeth were deteriorating somewhat (P13)
2. Should brush twice a day, but I think it’s too late. [Laughs] You know? I’ve only got eleven bottom teeth left (P28)
3. I brush, I use the toothpaste that you buy from the chemist. Like I try and do everything but there’s nothing that can sort of save them—now it’s
just sort of trying to prevent more damage but I just want them ripped out. Just give me dentures, I don’t care (P7)
4. Well, I’ve never liked them. They’ve always been crooked. And now they’re just- they just keep falling out. They’re just no good (P26)
Low prioritisation of oral health
5. Well, up until two years ago I suppose, or a year and a half ago, I didn’t sort of think about it too much. Occasionally I’d go to the dentist and get
a filling here and there. But for some reason, in the last two years, my teeth have deteriorated pretty badly. So, you know now, it’s pretty important (P2)
6. Oh, I think it’s just, I never considered looking after them- it’s just laziness I guess. It’s not part of my normal routine [laughs]. But it is becoming part
of my normal routine. I have a lot of other health issues and I’ve been concentrating on them more (P8)
7. People have to realise the importance and that’s what motivates you. You know? The importance. I mean, look at all the people that gave up smok-
ing when those adds came out with those horrible things on the packets (….). When they saw those images. Yeah. I think if people knew what can
happen to you, when you don’t look after your teeth. Maybe warnings, you know? (P21)
8. I tend to neglect my health a little bit. I suffer from depression and I get days when I can’t do anything (P2)
Misconceptions about preventive oral health practices
9. Well, you know, the bottom line is to be able to go and get these problems looked at on a regular basis (…….) I’d love to be able to – when I’ve got
an abscess or a toothache or whatever – that I could just- because sometimes you have to wait quite a while and when you’ve got an abscess (P21)
10. If you’re younger you don’t need to check your teeth every year. You can check ten years or twenty years. But after fifty years of old, you need one
year. Like I see my eye doctor, and my ears doctor, every one year (P5)

perform routine oral hygiene practices due to laziness, misconceptions regarding how smoking might affect
and also because they prioritised other health issues the teeth (Table 5, quote 12). Importantly, several par-
over oral health (Table 4, quote 6–8). Previous bad den- ticipants did not know why their oral health had dete-
tal experiences resulted in fear and avoidance of dental riorated (Table 5, quote 13).
treatment (Table 6, quote 5). There were also misconcep-
tions reflected in a belief that dental visits were required Understanding
to address problems rather than for routine preventive Many participants had little difficulty with this domain
care (Table 4, quote 9). One participant commented that which included the ability to read written information
routine dental visits were not required for young people provided by a dentist, and the ability to read general oral
(Table 4, quote 10). health information found in dental clinics. The qualita-
Another reason for reduced receptivity was limited tive data explored the details on preferences for receiv-
knowledge and education, which resulted in reduced ing information. Although over 50% of participants were
awareness of the impact of poor oral health on gen- happy with educational material being delivered by a
eral health beyond the local effects upon the dentition variety of sources including electronic or hard copy for-
and chewing function (Table 5, quotes 1–4). General mat, some formats such as text messages were reported
health impacts that were reported included the impact as an acceptable format by only 3 participants. An older
on mental health (Table 5, quote 5), and a personal participant explained how written material was some-
experience relating to a brain infection stemming from times hard to follow if it contained too much jargon
a tooth abscess (Table 5, quote 6). One participant (Table 6, quote 9). Face-to-face interactions were pre-
reported that poor oral health was likely to impact ferred by 3 participants (Table 6, quote 15).
their general health but was unaware of what these
impacts might be (Table 5, quote 7). There was also Utilisation
limited knowledge about the causes of poor oral health. The domain of utilisation is listed twice in the HeLD-14
Whilst there was acknowledgement that routine clean- assessment; in the first instance it relates to the availabil-
ing was important (Table 5, quote 8), there was very ity of support for dental visits and in the second instance
limited understanding of the role of diet. Participants to the ability to act on information received.
alluded briefly to the impact of acid (Table 5, quotes Although the need for support to attend dental visits
9–10) and sugar (Table 5, quote 11) on oral health. scored below 3 it was rarely mentioned in the interviews
There was broad awareness that smoking was likely to apart from one participant who reported that they were
negatively impact oral health, however there were also dependent on community transport (Table 6, quote 8). In
King et al. BMC Public Health (2023) 23:1446 Page 6 of 10

Table 5 Limited knowledge and education about oral health

Limited knowledge about the consequences of poor oral health

1. Bad breath, cavities, gum disease, gingivitis – I think that’s what it’s called – that can come about as well. Also tooth loss, mouth ulcers (P28)
2. Like a lot of it (poor oral health) is appearance to be honest. I can’t smile at all. Like I’ll smile with my lips closed (P7)
3. I can’t eat certain foods that I used to be able to ‘cause I’m just missing basically a lot of teeth. It just takes me so long to chew food and it just takes
the enjoyment out of eating (P19)
4. sometimes you have to wait quite a while and when you’ve got an abscess—I don’t know if you’re familiar with how painful they are (….) but it’s
extremely, extremely painful
5. it impacts your system, impacts how you feel about yourself. If you don’t feel good about yourself, you know what I mean? You won’t socialise, you
won’t smile, all that sort of stuff, you know? Which impacts on your overall mental health in my opinion (P38)
6. I had a sister in 1957 who got an abscess on a lower jaw and she finished up with an infection in her brain and she got encephalitis (P21)
7. Well, I suppose if you let it go… You know, your whole system is going to suffer. But I don’t think mine has. So, I can’t really comment on that with
any certainty (P19)
Limited knowledge about the causes of poor oral health
8. Neglecting the routine cleaning and that sort of thing (P1)
9. Lemon juice actually rots your teeth. It burns off the veneer (…….) and you know literally ruins your teeth (P22)
10. I don’t know, I love biccies, I love cake and I say that that might be what’s done a lot of damage (P21)
11. I had stomach surgery and it caused a lot of, like, acid. There was a lot of reflux and so, that started to eat away at my teeth …. (P7)
12. You know, I lost my teeth because I was a heavy smoker. Kind of like self-inflicted misery. It’s gum disease of the upper teeth. Heavy smokers get it.
But they don’t lose their bottom teeth, they lose their upper teeth. It doesn’t really affect the bottom teeth much (P28)
13. Although I’ve got a lot of problems with my teeth and you would say, well what have I done wrong for my teeth to be this way? But I’m not sure. I
don’t know (P2)
Limited oral health education
14. Oh! He would tell me, you know, because I have teeth out and he said, “[P17’s name], you shouldn’t do this and do that”. If I went to the dentist.
But I never receive anything to read (P17)
15. To tell you the truth I’m going back- every dentist I’ve had, I can’t honestly remember any of them, giving me any literature or anything
about dentistry to sort of, you know, save my teeth other than the one that told me that, um, basically I’d smoke my teeth to death (P22)

terms of carrying out instructions and acting on advice, Access

the interviews did reveal some areas of need. Providing The domain of access asks about their knowledge on
the rationale for preventive practices was reported to how to get a dental appointment, and their knowledge
be more helpful in achieving behaviour change (Table 6, on what to do to get a dental appointment. Although
quote 14). Oral health care instructions from oral health these items scored above 3 indicating that most partici-
care providers were welcomed and would have been pants did not have difficulties with access, there were
appreciated when the participants were younger (Table 6, several participants who commented that they had been
quote 17). Significantly one participant noted that a lack unaware of the availability of the public dental services
of information from their treating dentist made it difficult (Table 6, quote 11). Participants also commented that
to know how to manage their care in the future (Table 6, Government support to subsidise dental care (Table 6,
quote 10). quote 12), or work with insurance companies to make
care more affordable (Table 6, quote 13) would improve
Economic barriers their ability to attend dental visits. Other barriers that
The domain of economic barriers was the major con- might impact access included transport issues (Table 6,
tributing factor to low OHL in this study... Similarly, in quote 8).
the interviews over 50% of participants reported that
the cost of dental care limited their ability to see a den- Communication
tist (Table 6, quote 1). Cost also affected the ability to The domain of communication includes the ability to
seek routine care (Table 6, quote 2). One participant look for a second opinion and the ability to use infor-
commented that following retirement private health mation from a dentist to make decisions about oral
insurance was unaffordable and left them out of pocket health. Many participants had difficulty with the abil-
for dental expenses (Table 6, quote 3). Financial con- ity to look for a second opinion which likely relates
straints also resulted in participants seeking treatment to the economic barriers to accessing dental care and
from their medical practitioner for dental problems the dependence that these participants had on the
(Table 6, quote 4). public dental system. The interview analysis revealed
King et al. BMC Public Health (2023) 23:1446 Page 7 of 10

Table 6 Barriers and enablers to maintaining good oral health

Economic barriers
1. You asked me if I could afford to do this myself. The price I paid for that one filling is what I get for a fortnight. (…..) My pension is, $740 a fortnight,
and I either pay $640 for one tooth. So, [laughs] I can’t afford these things (P45)
2. In those days, only one parent worked, and we didn’t have money for dental health(….). You only went to a dentist if there was a problem (P38)
3. After retiring, we can’t afford the private health cover. It’s too much for two adults at that age to come out of your income. And there’s a lot of stuff
that they don’t cover anyway, you know, so you still of pocket whichever way you do it. I think there’s not enough cover for sure teeth, you know (P38)?
4. I needed to get a tooth pulled out because it had an abscess and I couldn’t afford it. So, I go to the doctor and get an antibiotic to stop the swell-
ing and get some more time until I could afford to do it (P2)
Other barriers (fear, long waiting lists, transport, poor delivery of oral health information)
5. I’ve seen her (current dentist) quite a bit. And I’m not so nervous now. But, you know, it’s one of the reasons why over the years, I haven’t visited
the dentist unless I really had to (P8)
6. I’m 72, 2015, my wife died. That was the last time I saw the dentist. I had a problem then, I booked in and—they said, “Oh, you know, it’ll be a three
year wait (P22)
7. I honestly think we’ve got a very good health system here, but not enough in the dental. I waited now for years and I haven’t heard from them
(P38)
8. Yeah, I have to depend on community transport. So, I’ve got to book that a week in advance (P8)
9. sometimes when they send an email, they put a hell of a lot of garbage in with it and they put different, words in that- I can’t remember. I’m look-
ing for a word that fits… jargon. They put jargon in and to me, if you put jargon into me, it’s straight out (P22)
10. They’re not taking them all out. I’m not sure. They haven’t really talked to me too much about what I can get as far as replacement teeth or any-
thing like that (…..)there was no talk about what they can do for me or what I should do in the future to address the issues (P2)
Enablers: Better information about available oral health services and support for oral health care
11. This is a free dental health check-up. I happen to know it through Service New South Wales when I went there and they told me that there are
some benefits and discounts for seniors (…….) without me being at the Service New South Wales office I wouldn’t know that there is such a thing (P1)
12. They (different state) pay- I think she said it was like a $120 or something like that. Like quite a small amount and then they get something
like $1800 worth of dental care and they get that every year (….) I would pay that, you know, even $200 or $300, I could afford that (P7)
13. It would be good also if the state government or even the federal would tie up with the private insurance companies to make the cost of oral
health more affordable (P1)
Enablers: Better delivery of oral health information
14. He actually sat down and had a discussion and told me that I should do this and I should do that. And he gave me reasons why. He didn’t just
turn around and say, “You got to brush your teeth! He actually explained why I should brush my teeth, why I should do this and, and all that. And I
listened (P22)
15. You know exactly where you stand when it’s face-to-face. (….) if you don’t understand when you’re face-to-face you can ask the questions, “Is this
what you’re talking about? Is this correct?” You can’t- well, you can, but it’s a very convoluted thing with any other form (P19)
Other enablers (universal dental records, oral health advice)
16. if you go to a different dentist than what you went to previously, (…) they don’t have the records (….) So, you have to explain things over again
and sometimes you don’t understand it yourself. So, if there was some record keeping that would be really cool (P7)
17. Well, it’s the brushing method, the length of time (…).. They also told me about not rinsing off the toothpaste. And they got me using those little
Christmas tree pics as well. I’m sorry I was 75 before I learned all this. It would’ve been handy to know 50 years ago (P21)

that the long waiting times in the public system were Discussion
a significant barrier to obtaining dental care (Table 6, This mixed-method study has provided insights into the
quote 6). There was acknowledgement that the overall multiple factors affecting OHL in a social disadvantaged
health system was quite good but that the dental sys- population. This study demonstrates that while OHL may
tem was not (Table 6, quote 7). Additionally, the lack be improved by more targeted communication and edu-
of universal dental records made it hard to transfer to cation strategies, these need to be supported by service
different dentists (Table 6, quote 16). Of note is that level and systemic changes to reduce barriers to preven-
almost all participants reported that they had received tive oral health care. Almost half the study population
very limited oral health information in the past had low to medium OHL, and many had poor oral health
(Table 5, quotes 14–15). Several mentioned that they as reflected in the levels of tooth loss and the proportion
had received the information very late in life and that brushing once a day or less. Analysis of the interview data
it would have been more helpful to receive this when revealed 3 major themes including attitudes and percep-
they were younger and that they appreciated informa- tions about oral health, limited knowledge and education
tion on brushing technique, use of interdental brushes about oral health, and barriers and enablers to maintain-
(Table 6, quote 17). ing good oral health.
King et al. BMC Public Health (2023) 23:1446 Page 8 of 10

Poor understanding of the impact poor oral health those with higher oral health literacy were more likely to
could have on their general health was a key factor affect- engage in preventive dental care [29]. The lack of agency
ing the ability of participants to pay attention to their oral many participants felt in relation to their oral health may
health. The impact of poor oral health, particularly gum be due to this lack of oral health knowledge and is likely
disease on oral health is well established. Evidence from compounded by social disadvantage. This disadvantage is
observational studies have consistently shown that peri- reflected in the fact that the highest level of educational
odontitis (gum disease) increases the risk for poor CVD attainment for 45% of the study population was at the
outcomes [7], increases the risk of developing hyperten- high school level (and for 8% at the primary school level).
sion [8] and has a bidirectional relationship with type 2 The findings from this study are consistent with evidence
diabetes mellitus (T2DM) [9]. Furthermore, there is now that indicates that poor OHL is associated with poor oral
a growing body of evidence to suggest that tooth loss is health outcomes, poor oral health behaviours [14] and
associated with other general health conditions such as poor oral health knowledge [30].
cognitive decline [23], and frailty [24]. However, despite Although the participants in this study scored well on
this evidence many focused on the local effects such as items relating to using information from a dentist the
pain, tooth loss, and the impact on diet and appearance. interview data suggests that many participants received
Similar findings have been reported in patients with very little information on oral health, and that when
CVD, where despite a high incidence of oral health prob- information was received it was from their dentist. Pre-
lems many lacked knowledge about the importance of ventive information delivered by oral health care practi-
good oral health and the association between poor oral tioners has been shown to improve oral health outcomes,
health and heart disease [17]. Furthermore, although particularly in reducing tooth decay [31]. However, lim-
many claimed to value oral health, they often listed it as a ited access to oral health care means that access to pre-
low priority until problems developed. ventive information is also limited. Our findings are not
Most participants understood that oral hygiene prac- dissimilar to a large qualitative study involving 6 Euro-
tices such as tooth brushing, interdental cleaning were pean countries and over 140 participants that reported
important in maintaining good oral health. However, a lack of patient education and oral health awareness
despite established recommendations for twice daily across Europe [32].
brushing, 38% of interview participants and 40% or sur- The major factor that contributed to a low OHL score
vey participants were only brushing once a day or less. were the economic barriers, and this was consistent with
This may be explained by the sentiment expressed by the interview data that highlighted financial issues as
some that they did not feel there was any point in try- the main reason participants were not able to seek den-
ing to look after their teeth as they were too far gone. tal care. Nationally, Australian Bureau of Statistics data
The goal of tooth brushing and interdental cleaning is to report that every year 2 million Australians defer visits
reduce the oral bacterial load. The build-up of oral bac- to a dentist due to cost [33]. Internationally, in a 2014
teria triggers a localised inflammatory response in the National Health Interview survey from the United States
tissues which can escalate and contribute to the overall of America the cost of treatment as a barrier to accessing
inflammatory risk profile for diseases such as CVD [25]. care was reported by more people for dental care com-
A cohort study of over 200,000 participants found that an pared to any other type of health care [34]. The inter-
additional brushing of the teeth per day was associated view data identified that the cost of dental care limited
with a 9% reduction in the risk for CVD [26]. not only access to see a dentist, but also the treatment
Many participants in the study had poor oral health options and the ability to receive routine care.
knowledge about key preventive oral health behaviours. Taken together the findings from this study suggest
Sugar consumption has a significant impact on the risk that there is a critical need to engage with the community
for tooth decay [27], yet it was mentioned by only a few to improve awareness of the broader implications of poor
participants. Consuming adequate water to ensure hydra- oral health on general health and to improve the deliv-
tion helps maintain saliva flow which in turn protects ery of preventive information. The focus of dental care
against both tooth decay and gum disease [28]. However is often on treatment rather than prevention [35]. How-
only one participant noted that they should drink more ever, dental disease is preventable, therefore a stronger
water. Other factors that can affect hydration such as caf- emphasis on preventive care will help reduce the com-
feine intake were not mentioned and even the impact munity burden of dental disease. Delivering preventive
of certain medications on saliva flow was poorly under- information using multiple platforms including digital
stood. This lack of knowledge about general preven- media and better utilisation of the dental team (the den-
tive behaviours in a population with low-medium OHL tist, oral health therapists, hygienists and nurses) could
mirrors findings from a recent study that showed that improve information dissemination. Additionally, oral
King et al. BMC Public Health (2023) 23:1446 Page 9 of 10

health education could be integrated into chronic disease Abbreviations

BMI Body mass index
management such as diabetes counselling, cardiac reha- CVD Cardiovascular disease
bilitation, and healthy aging programmes. Despite shar- HeLD-14 Health Literacy in Dentistry scale
ing common risk factors, oral health information is often OHL Oral health literacy
REDCap Research electronic data capture
limited or absent from these programmes and there is a SES Socioeconomic status
growing awareness of the need for better integration of T2DM Type 2 Diabetes Mellitus
oral and general health care [36]. WHO World Health Organisation
WCOH Westmead centre for oral health

Strengths and limitations Supplementary Information

The strength of this study is the richness of the interview The online version contains supplementary material available at https://​doi.​
data from a diverse population group with a high bur- org/​10.​1186/​s12889-​023-​16381-5.
den of dental disease. This data provides insight into how
future oral health messaging and prevention strategies Additional file 1. Interview guide

could be designed for diverse and higher risk population

groups. Acknowledgements
We would like to thank Dr Josephine Kenny and Dr Ilana Fisher from the West-
One of the limitations is that although participants
mead Centre for Oral Health for their operational support of the project.
in this study were drawn from a range of cultural back-
grounds, we were not able to include non-English Authors’ contributions
SK, LL BS and JE designed the study, SK and AT conducted the study. SK, AT
speaking participants due to the lack of funding for and LL analysed the data, SK drafted the manuscript, All authors reviewed and
translation services. Furthermore, participants were not provided final approval of the manuscript.
provided with the opportunity to review or edit their
Funding
comments, and this may impact the validity of the con-
This study was supported by a research grant from the Westmead Applied
clusions. Another limitation is the small sample size Research Centre. The grant provided seed funding which funded a research
and method of participant selection using convenience assistant to conduct and transcribe the interviews.
sampling. These issues limit the ability to generalise Availability of data and materials
the findings from this study to the broader population. The datasets used and/or analysed during the current study are available from
Finally, findings regarding the perceived lack of control the corresponding author on reasonable request.
and resignation about oral health status may be skewed
due to the older age of participants in this study. How- Declarations
ever, this is an important finding as any oral health Ethics approval and consent to participate
information designed for older adults should address The study was approved by the Western Sydney Local Health District Human
these issues. Future studies could focus on using trans- Research Ethics Committee (protocol number: 2021/ETH12053). All participants
provided written informed consent prior to any data collection. All methods
lation services to collect information from non-English were performed in accordance with the relevant guidelines and regulations.
speaking participants to get a broader understanding of
oral health related knowledge, attitudes and perceptions Consent for publication
Not applicable (the study does not report any identifiable data).
of these individuals.
Competing interests
The authors declare no competing interests.
Conclusion
This mixed methods study identified that in a socially Received: 20 March 2023 Accepted: 25 July 2023
and culturally diverse population of Australian adults
with a high burden of oral disease, many have low to
medium oral health literacy. The major factor contrib-
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