J Clin Exp Dent. 2019;11(12):e1143-50.

Oral health knowledge and educational level

Journal section: Community and Preventive Dentistry doi:10.4317/jced.56411

Publication Types: Research https://doi.org/10.4317/jced.56411

Oral health knowledge in relation to educational

level in an adult population in Spain

Cecilia-Fabiana Márquez-Arrico 1, Jose-Manuel Almerich-Silla 2, Jose-Maria Montiel-Company 2

1
Master degree, DDS, pre-doctoral research. Department of Stomatology, University of Valencia, Spain
2
Lecturer Professor. Department of Stomatology, University of Valencia, Spain

Correspondence:
Clínica Odontológica
Universitat de València
C/Gascó Oliag 1
Valencia (46010), Spain
dra.cecilia.marquez@gmail.com Márquez-Arrico CF, Almerich-Silla JM, Montiel-Company JM. Oral
health knowledge in relation to educational level in an adult population in
Spain. J Clin Exp Dent. 2019;11(12):e1143-50.
Received: 08/10/2019 http://www.medicinaoral.com/odo/volumenes/v11i12/jcedv11i12p1143.pdf
Accepted: 04/11/2019

Article Number: 56411 http://www.medicinaoral.com/odo/indice.htm

© Medicina Oral S. L. C.I.F. B 96689336 - eISSN: 1989-5488
eMail: jced@jced.es
Indexed in:
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Pubmed Central® (PMC)
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DOI® System

Abstract
Background: To analyze the relationship between oral health knowledge and educational level among an adult
population in Spain, and between oral health knowledge and subjects’ oral hygiene practices, dietary habits, toxic
habits, and oral quality of life.
Material and Methods: This transversal study used the Comprehensive Measure of Oral Health Knowledge (CMO-
HK) questionnaire to evaluate subjects’ knowledge and understanding of oral health, and the World Health Orga-
nization oral health questionnaire for adults to evaluate dietary, oral hygiene, toxic habits, and oral quality of life.
Participants (n=400) gave their informed consent and data release permission before taking part in the study, which
was approved by the University of Valencia Ethics Committee (certificate No.: H145160675341). Statistical analy-
sis was performed using SPSS v22.0 software, applying Student’s t-test, ANOVA, and chi2 test, with significance
set at p<0.05.
Results: Oral health knowledge results were: low 41.5% and high 58.5%. An association was found between educa-
tional level and oral health knowledge (Chi2: p=0.000). Oral hygiene habits presenting an association with higher
levels of oral health knowledge were dental floss use, a higher number of teeth present, and lower prevalence of
partial prostheses. A significant association was found between oral quality of life and oral health knowledge.
Conclusions: Oral health knowledge is associated with the individual subject’s educational level. But oral health
knowledge is not necessarily reflected in the practice of healthy habits.

Key words: Oral health literacy, oral health habits, oral health knowledge, CMOHK.

Introduction of the healthcare services available and to make deci-

Oral health education is a fundamental tool for the pre- sions, both individually and collectively, to improve both
vention of most bucodental diseases. This aims to induce their oral health and circumstantial factors affecting oral
subjects to adopt and maintain healthy habits, make use health. Over the last ten years, a number of researchers

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have developed tools for measuring knowledge and un- It is known that a person’s behavior in terms of daily oral
derstanding of oral health issues and practices among hygiene, nutrition, and toxic habits (such as smoking
adults, as awareness is the first step towards a healthy and drinking alcohol) does not depend on awareness
lifestyle. The tools available for measuring oral health and understanding of oral health issues but is subject to
knowledge are based on assessments of understanding, much more complex processes. In addition to knowle-
knowledge, identification or a combination of these, by dge and awareness, for an individual to acquire good
means of short questions and/or multiple choice questions oral hygiene habits, he/she must be motivated to adopt
about oral health and bucodental hygiene practices (1). good habits, supported by circumstances and resources
Using oral hygiene questionnaires helps to assess the effi- that make it possible to carry out these practices, among
cacy of healthcare interventions, dental caries prevention other factors (6). This means that although a subject may
campaigns, or anti-smoking campaigns, among others. have good knowledge and understanding of oral health-
Although there are many questions concerning oral health care, this is not necessarily reflected in his/her everyday
habits, the use of a standardized method such as the World oral health habits.
Health Organization (WHO) questionnaire, will help to At the same time, it is useful to obtain information about
compare and contrast the results and obtain homogeneous the socio-economic levels within a study population, as
data for planning healthcare programs (2). this is usually an influential variable in the prevalence of
One of the most widely used questionnaires for measu- bucodental pathology. In 2015, an epidemiological study
ring oral health literacy in adults is the REALD ques- of oral health in Spain found that dental caries and perio-
tionnaire “Rapid Estimate of Adult Literacy in Den- dontal disease (among other bucodental characteristics
tistry” (3). The first version of this questionnaire was and pathologies recorded in the study) were more preva-
created by Richman et al. in 2007, based on REALM, lent at lower socio-economic levels in both children and
a questionnaire created for assessing general medical adults (7). Transversal studies are able to identify those
literacy. The REALD-99 consisted of 99 items with a groups more susceptible to bucodental disease as well as
simple point-scoring method; patients are asked to read those who have not received sufficient health education.
lists of oral health terms, awarding one point for every The main objective of this study was to analyze the rela-
word read and pronounced correctly, obtaining a maxi- tionship between oral health knowledge according to the
mum score of 99 points. This instrument made it pos- CMOHK questionnaire, and educational levels, oral hy-
sible to compare the scores obtained and analyze their giene habits, age, and sex in an adult population. It also
associations with other socio-demographic variables analyzed the relationship between levels of oral health
such as age, sex, educational levels, and other variables knowledge and oral quality of life.
recorded in the questionnaire. As this is a lengthy ques-
tionnaire, it was decided to create a shorter version, wi- Material and Methods
thout compromising the validity of the original, which This transversal study took the form of a survey based
led to the REALD-30, launched in 2007 by Lee et al. (3). on questionnaires, one evaluating oral health knowled-
The REALD and the REALM are valid tools for evalua- ge, and another oral hygiene habits, among a population
ting oral health literacy, but they do not assess subjects’ of adult (aged over 18 years) male and female Spanish
real understanding of oral healthcare. Subjects are often dental patients and the individuals accompanying them.
familiar with a term, and can pronounce it correctly, but The survey was conducted at the Dental Clinic at the
it remains unclear whether he/she really understands its University of Valencia. Field work was carried out be-
meaning. So, to fill this gap, the ToFHLiD6 (functional tween September 2017 and June 2018 (n=400).
understanding of oral health terminology and numerical The questionnaires were completed in the waiting rooms
capability) Test of Functional Health Literacy in Den- at the University of Valencia Dental Clinic, and were fi-
tistry was developed in 2007 (4). This tool assesses the lled out by both patients and individuals accompanying
subject’s understanding and numerical capability, and them. Each subject was provided with full information
was the first tool available for evaluating real unders- about the study objectives and gave their informed con-
tanding of oral health matters (1). In 2010, Macek et al. sent to take part and data release permission. The study
created a questionnaire that combined the REALM (oral protocol was approved by the University of Valencia
health literacy) and the ToFHLiD. This tool was named Ethics Committee (Certificate no. H145160675341).
the Comprehensive Measure of Oral Health Knowledge When the informed consent form had been signed, the
(CMOHK) (5) and was validated by the University of subject was given two questionnaires (one to evaluate
Maryland (USA). The advantage of the questionnaire is oral health knowledge and another to assess oral hygiene
that as well as measuring whether a subject is capable habits and other variables). When completed, both ques-
of understanding concepts relating to oral health, it also tionnaires were returned to the surveyor who remained
determines whether he/she possesses basic knowledge present throughout the process to answer any questions.
of different dental pathologies. Each participant was allotted an identification number.

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Thereafter each participant remained anonymous, as did undergone vocational training; a high level comprised
all personal data such as age, sex, profession, and edu- subjects who had completed higher education to degree
cational level. or post-graduate level.
-Questionnaires -Sample size calculation
The CMOHK questionnaire was used to evaluate sub- It was calculated that a random sample of 389 indivi-
jects’ oral health knowledge (5). This consists of 26 duals would be sufficient to estimate, with a 95% con-
multiple-choice questions with only one correct answer. fidence interval (CI) and +/- 0.45 units precision, a po-
Questions 1-3 evaluate dental variables, which do not pulation mean obtained by the CMOHK of 15.2 points,
contribute to the oral health knowledge results, but pro- which was predicted to show a standard deviation of
vide other information for further analysis. The CMO- around 4 units. The replacement percentage necessary
HK awards a point for each question answered correctly, was predicted to be 20%. To make this calculation, data
making a total maximum score of 23 points, sub-divi- were used from a pilot study using the same methods
ded into domains corresponding to areas of bucodental applied to a similar population of 171 subjects.
knowledge and understanding. The CMOHK questions -Statistical analysis
are grouped as six domains: 1. General dental knowled- Statistical analysis was performed with SPSS 22.0. Sof-
ge (questions 4, 6, 25, and 26); 2. Knowledge about chil- tware. For quantitative variables, means and confidence
dren`s oral health, disease and prevention (questions 5, intervals were calculated, while proportions were cal-
7, 13, and 21). 3. Knowledge of oral disease prevention culated for categorical variables. Student’s T-test and
(questions 9, 11, 12, and 16); 4. Knowledge of dental analysis of variance (ANOVA) were used to compare
treatments (questions 8, 10, 17, 18, and 20); 5. Knowled- means. The Chi2 test was used to compare proportions.
ge of periodontal disease (questions 19, 22, 23, and 24); Statistical significance was set at p<0.05. Logistic re-
6. Knowledge of oral cancer (questions 14 and 15). Fo- gression was performed using the forward conditional
llowing the method described by Patiño et al. in 2015, method with low oral health knowledge as dependent
two levels of knowledge were determined: low level of variable and age and educational level as predictive va-
knowledge (0-14 points), high level of knowledge (15- riables.
23 points).
The WHO oral health survey fifth edition (2013) was Results
used to evaluate oral health habits, which also records -Descriptive results
age, sex, educational level (question 16) as demogra- A total of 439 participants handed in questionnaires,
phic and socio-economic variables. The questionnaire of whom 412 had completed them (a response rate of
records the number of teeth present, the presence/ab- 93.84%). Twelve subjects were discarded, eight becau-
sence of removable prostheses, and how subjects view se various options had been marked in multiple choice
their own oral health. Subjects are asked about their oral questions, two because only one of the two questionnai-
hygiene practices including the frequency of tooth brus- res had been completed, and two because the subjects
hing, use of dental floss, mouthwashes, interspace brus- could not read Spanish. Therefore, a total of 400 sub-
hes, etc. Questions 10 and 11 record the frequency of jects were included in analysis. Of the 400 participants,
visits to the dentist and the reasons for them. The survey 237 were women (59.3%) and 163 men (40.8%). The
has a section that records 12 oral quality of life items mean age of the sample was 45.2 ± 13.7 years. Regar-
(question 12), and nine items concerning the consump- ding age groups, 144 participants were aged between
tion of sugary foods and drinks (question 12), and toxic 18 and 40 years (36.4%), 172 between 41 and 55 years
habits (alcohol consumption and smoking) (Questions (43%) and lastly 83 subjects were aged over 55 years
14 and 15). (20.8%). Subjects’ educational level was low in 20.0%
To calculate odds ratios (OR) of significant variables, cases, medium in 38.3%, and high in 41.8%. The mean
it was necessary to dichotomize oral quality of life va- score obtained in the questionnaire was 14.7 points (IC-
riables as two categories. Category 1 grouped respon- 95% between 14.3 and 15.1). The scores obtained were
ses related to discomfort reported to be very frequent or classified as two levels of oral health knowledge: low
fairly frequent, while the category 0 grouped responses level (<14 points) 41.5% (n=116) and high level (>14
that reported no discomfort during the last 12 months. points) 58.5% (n=234).
To assess the relationship between levels of oral heal- -CMOHK questionnaire results
th knowledge and educational level, educational levels The mean score obtained in the CMOHK was signifi-
were categorized as one of three groups (low, medium cantly higher among young subjects (18-40 years). As
or high). A low educational level consisted of subjects age increased the mean score obtained, both in the total
who had not received any formal schooling or had not score and subdivided scores allotted to the questionnai-
completed primary education; medium included sub- re’s different domains decreased significantly. When
jects who had completed secondary education or had the results were analyzed according to sex, women

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achieved a significantly higher mean score than men, a tor for a low level of oral health knowledge, compared
pattern repeated in the domains “Children’s oral heal- with subjects with medium or high educational levels
th, disease and prevention” and “Periodontal Disease.” (OR 1.929). Age was also found to be a predictive fac-
Educational level also showed a relationship with mean tor of a low oral health knowledge level. Older subjects
CMOHK scores. Subjects with a high educational level were shown to show almost 2% greater risk of having a
(subjects who had completed higher education to degree low level of oral health knowledge (OR 1.015) (Table 3).
or post-graduate level) obtained a significantly higher -Association between habits and oral health knowledge
mean score both in overall scores and in individual do- Oral hygiene habits that showed an association with a
mains, compared with subjects with medium and low higher level of oral health knowledge were: use of dental
educational levels (Table 1). floss (49.1% of subjects with a high level of oral health
When the results were analyzed in terms of oral health knowledge used dental floss in comparison with 28.9%
knowledge levels, it was seen that subjects who had rea- of subjects with a low level of knowledge [p=0.000]);
ched higher educational levels had significantly higher higher number of teeth present (82.9% of subjects with
levels of oral health knowledge than subjects with me- a high level of knowledge also presented 20 or more
dium or low educational levels. A linear tendency could natural teeth compared with 67.9% of subjects with a
be observed between the categories (p=0.000) whereby low level of knowledge [p=0.004]); and lower incidence
as educational level increased, so did the percentage of of removable partial prostheses (22.3% of subjects with
individuals with a high level of oral health knowledge. a low level of oral health knowledge had a removable
The same tendency was observed with the age variable, partial prosthesis compared with 12.4% among subjects
so that younger subjects (18-40 years) obtained signi- with a high level [p=0.009]). Frequency of tooth brus-
ficantly higher average oral health knowledge scores hing, the use of mouthwashes and inter-space brushes
(Table 2). did not present significant associations with levels of
A low educational level was found to be a predictive fac- oral health knowledge.

Table 1: Mean CMOHK scores by domain, in relation to age, sex, and educational level.
Domains Age Mean ANOVA Sex Mean Student- Level of Mean ANOVA
(IC95%) test p (IC95%) test education (IC95%) test p
value p-value value
General 18-40 years 2.6(2.5-2.8) 0.010* F 2.4(2.3-2.5) 0.813 Low 2(1.8-2.3) 0.001*
dental 41-55 years 2.4(2.3-2.6) Middle 2.5(2.3-2.6)
knowledge 2.4(2.3-2.6)
>55 years 2.2(1.9-2.4) M High 2.6(2.4-2.8)
C h i l d r e n`s 18-40 years 2.3(2.1-2.5) 0.007* F 2.4(2.2-2.5) 0.000** Low 1.7(1.4-1.9) 0.000**
oral health, 41-55 years 2.3(2.1-2.5) Middle 2.1(1.9-2.3)
disease and 1.9(1.7-2.1)
prevention >55 years 1.9(1.6-2.1) M High 2.5)2.3-2.6)
Oral disease 18-40 years 2.7(2.5-2.8) 0.095 F 2.6(2.5-2.7) 0.108 Low 2.3(2.1-2.5) 0.000**
prevention 41-55 years 2.6(2.5-2.8) Middle 2.4(2.3-2.6)
2.4(2.3-2.6)
>55 years 2.4(2.2-2.6) M High 2.8(2.6-2.9)
K nowle d ge 18-40 years 4.2(4.1-4.3) 0.184 F 4.2(4.1-4.3) 0.131 Low 3.9(3.6-4.1) 0.01*
pertaining to 41-55 years 4.2(4.1-4.4) Middle 4.1(3.9-4.2)
dental 4(3.9-4.2)
treatment >55 years 4(3.7-4.3) M High 4.3(4.2-4.8)
Per iodontal 18-40 years 2.4(2.2-2.6) 0.013* F 2.4(2.2-2.5) 0.040* Low 1.8(1.5-2.1) 0.000**
disease 41-55 years 2.4(2.3-2.6) Middle 2.2(2.1-2.4
2.1(1.9-2.3)
>55 years 2(1.7-2.3) M High 2.6(2.4-2.7)
K nowle d ge 18-40 years 1.1(1-1.2) 0.035* F 0.9(0.8-1) 0.307 Low 0.7(0.5-0.9) 0.000**
pertaining to 41-55 years 0.9(0.8-1) Middle 0.9(0.7-1)
oral cancer 0.9(0.8-1)
>55 years 0.8(0.7-1) M High 1.1(1-1.2)
Total 18-40 years 15.3(14.7-15.9) 0.001* F 15.1(14.6- 0.010* Low 12.6(11.5- 0.000**
15.6) 13.6)
41-55 years 15(14.4-15.6) 14.1(13.4- Middle 14.4(13.8-15)

>55 years 13.2(12.2-14.3) M 14.7) High 16(15.2-16.5)

*p<0.05; **p<0.001; F= Female; M= Male

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Table 2: Association between oral health knowledge according to CMOHK and variables age, sex, educational level.
Oral Health Age N (%) Chi 2 p- Sex N (%) Chi 2 p Level of N (%) Chi 2 p-
Knowledge value value education value
Score
Low level 18-40 years 55(38.2) F 99(41.8) Low 49(61.3)
(0-14) 41-55 years 64(37.2) Middle 69(45.1)
0.014* 67(41.1) 0.894 0.000*
>55 years 46(54.5) M High 48(28.7)
High level 18-40 years 89(61.8) F 138(58.2) Low 31(38.8)
(15-23) 41-55 years 108(62.8) Middle 84(54.9)
96(58.9)
>55 years 37(44.6) M High 119(71.3)
*p<0.05; **p<0.001; F= Female; M= Male

Table 3: Logistic regression model, with forward conditional method.

Low level of oral health knowledge according to CMHOHK
B SD p OR (IC 95%)
Age 0.015 0.008 0.056 1.015 (1.000-1.031)
High level education (Category reference) - - - -
Medium level education 1.214 0.297 0.000** 3.367 (1.882-6.024)
Low level education 0.657 0.238 0.000** 1.929 (1.209-3.077)
**p<0.001

Smoking and alcohol consumption did not present signi- hip between oral health knowledge levels and educatio-
ficant associations with levels of oral health knowledge. nal levels. The mean score obtained using the CMOKH
Nor was any significant association found between the was very similar to the score obtained by Patiño in 2015
consumption of sugary foods and drinks and oral health (around 14 points). Macek et al. (2010) and Naghibi et
knowledge. al. 2014) (8) found that the domain with the lowest sco-
-Oral quality of life results in relation to CMHOK oral res was knowledge of oral cancer, while the highest sco-
health knowledge levels re was for knowledge of dental treatments.
The overall oral quality of life variable was calculated by The incidence of cancer of the lips and oral cavity va-
totaling each of the sections in Question 12 of the WHO ries according to geographical area and population.
oral health questionnaire. According to this instrument, Globally, oral cancers represent 3.8% of all cancers.
the higher the score obtained, the higher the subject’s Worldwide, it is estimated that there are 529.500 new
level of oral quality of life affectation. To determine the cases of oral cancer annually, leading to 292.300 dea-
relationship between oral quality of life and oral health ths. Cancer of the lip, mouth and throat occupies four-
knowledge level, Student’s T-test was applied compa- teenth place among all tumors. In Spain, 4,980 new ca-
ring the mean quality of life score obtained by subjects ses of lip, mouth or throat cancer are recorded among
with high and low levels of oral health knowledge. Sub- men annually, and 1,690 new cases among women (per
jects with low knowledge levels reported “Difficulty in 100,000 persons per year). Every year, 1,500 Spaniards
biting foods,” “Difficulty with speech/trouble pronoun- lose their lives to oral cancer but only 20-30% of oral
cing words,” “Felt tense because of problems with teeth cancers are diagnosed at early stages (9). Oral cancer
or mouth,” “Have avoided smiling because of teeth,” is clearly a topic of great relevance and yet unaware-
“Have taken days off work,” and/or “difficulty doing ness of this oral health issue persists among the general
usual activities” (during the previous 12 months) with population.
significantly greater frequency than subjects with high Regarding levels of oral health knowledge in relation to
levels of oral health knowledge (Table 4). sex, more women were found to present higher levels
of knowledge than men. This agrees with other authors
Discussion (5,10,11) who found that women obtained significantly
The results obtained in the present study concur with higher scores in results grouped according to domain.
those obtained in other research analyzing the relations- The study by (12) also found that women obtained better

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Table 4: Results of WHO oral quality of life questionnaire. The chi-squared test was applied to analyze association between CMOHK
oral health knowledge level and oral quality of life.
Because of the state or your teeth or mouth, ¿How often have you Answer N (%) Chi
experienced any of this following problems? squared
p-value
12.1) Difficulty in biting foods Very often 23(5.8) p= 0.001*
Fairly often 23 (5.8)
Sometimes 69 (17.3)
No 263 (65.8)
Don’t know 20 (5.0)
12.2) Difficulty chewing foods Very often 24(6.0) p= 0.054
Fairly often 19 (4.8)
Sometimes 68 (17.0)
No 278 (69.5)
Don’t know 11(2.8)
12.3) Difficulty with speech/trouble pronouncing words. Very often 5 (1.3) p= 0.012*
Fairly often 9 (2.3)
Sometimes 24(6.0)
No 341 (85.3)
Don`t know 19 (4.8)
12.4) Dry mouth Very often 10 (2.5)) p=0.211
Fairly often 13 (3.3)
Sometimes 72 (18.0)
No 285 (71.3)
Don’t know 19 (4.8)
12.5) Felt embarrassed due to appearance of teeth Very often 20 (5.0) p= 0.137
Fairly often 31 (7.8)
Sometimes 70 (17.5)
No 261 (65.3)
Don’t know 16 (4.0)
12.6) Felt tense because of problems with teeth or mouth Very often 10 (2.5) p= 0.030*
Fairly often 19 (4.8)
Sometimes 54 (13.5)
No 291 (72.8)
Don’t know 19 (4.8)
12.7) Have avoided smiling because of teeth Very often 21 (5.3) p= 0.005*
Fairly often 14 (3.5)
Sometimes 45 (11.3)
No 303 (75.8)
Don’t know 16 (4.0)
12.8) Had sleep that is often interrupted Very often 14 (3.5) p= 0.412
Fairly often 11 (2.8)
Sometimes 36 (9.0)
No 319 (79.8)
Don’t know 20 (5.0)
12.9) Have taken days off work Very often 0 (0) p= 0,044*
Fairly often 0 (0)
Sometimes 5 (1.3)
No 373 (93.3)
Don’t know 17 (4.3)

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Table 4 continue: Results of WHO oral quality of life questionnaire. The chi-squared test was applied to analyze association between
CMOHK oral health knowledge level and oral quality of life.
12.10) Difficulty doing usual activities Very often 4 (1.0) p= 0.046*
Fairly often 3 (0.8)
Sometimes 13 (3.3)
No 361 (90.3)
Don’t know 18 (4.5)
12.11) Felt less tolerant of spouse or people who are close to you Very often 0 (0.0) p= 0.216
Fairly often 4 (1.0)
Sometimes 15 (3.8)
No 360 (90.0)
Don’t know 21 (5.3)
12.12) Have reduced participation in social activities Very often 3 (0.8) p= 0.191
Fairly often 7 (1.8)
Sometimes 11 (2.8)
No 358 (89.5)
Don’t know 19 (4.8)
* p <0.05.

results than men although without statistically signifi- Low socioeconomic level was found to be a risk factor
cant difference. for poor oral health knowledge and deficient oral hygie-
Investigating educational levels in relation to levels of ne habits (13). A similar relationship between socioeco-
oral health knowledge, it was observed that as subjects’ nomic level, oral hygiene habits and educational level
educational level increased, so did their level of oral was also found among a population in south-east Iran
health knowledge, with a linear tendency among the (17); this study with a sample of 264 adults, analyzed
categories. These results coincide with those obtained oral hygiene habits and levels of oral health knowledge.
in other studies, so that subjects who have not entered It was found that subjects who did not reach medium or
higher education obtained lower overall scores both in higher educational levels were not well informed or tra-
total scores and in scores for individual knowledge do- ined in correct oral hygiene maintenance, and were not
mains (10,12-15). aware of the importance of regular dental check-ups. It
Comparing the present results with data obtained in was also observed that women presented higher levels of
other countries and other populations, the association oral health knowledge than men (17,19).
between a subject’s oral health knowledge and age, In light of the above, the data obtained in different stu-
sex and educational level is consistent (12,13,16-18). dies conducted among different populations in different
A study conducted in China in 2019 with a sample of countries show great consistency in the association be-
263 middle-aged subjects found a significant relation tween educational level, oral health knowledge, and cer-
between age, low educational level, and low oral heal- tain oral health habits. Oral health education programs
th knowledge. Socioeconomic level also influenced oral aimed at groups with lower educational levels may pro-
health knowledge, whereby subjects with less purcha- ve useful to bring about a general improvement in oral
sing power showed lower levels of oral health knowle- health.
dge. Poor oral health knowledge was also associated It is known that quality of life is generally related to so-
with deficient oral hygiene and higher numbers of lost cioeconomic level, as purchasing power facilitates ac-
teeth. These results show how training in oral health is cess to goods and services, including oral healthcare. A
reflected in a subject’s capacity to maintain oral hygiene low socio-economic level has been seen to affect oral
and in the consequences, for example, retaining more quality of life (20). In the present study, it was seen how
healthy teeth (16). In agreement with the present study, a low level of oral health knowledge did not condition
it has also been shown how subjects who have comple- poor oral quality of life, but did influence factors such
ted higher education tend to adopt specific oral hygiene as pain/discomfort when chewing food, as well as pro-
practices such as dental flossing (7,12,16,18). A study of blems in speaking and pronunciation, these being rela-
360 middle-aged Slovak subjects found a significant as- ted to early dental loss and the presence of removable
sociation between higher education and dental floss use. partial prostheses, variables that were significantly more
At the same time, women who had completed higher frequent among subjects with low levels of oral health
education showed better oral hygiene habits than men. knowledge.
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The present study’s main limitation was that its trans- 10. Macek MD, Atchison KA, Chen H, Wells W, Haynes D, Parker
versal design was unable to signify causality. In addi- RM, et al. Oral health conceptual knowledge and its relationships
with oral health outcomes: Findings from a Multi-site Health Literacy
tion, the sample selection was not random as most of Study. Community Dent Oral Epidemiol. 2017;45:323-9.
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attending a dental clinic, a fact that may have compromi- panic adults in Iowa. 2015.
sed the representativity of the sample. Nevertheless, the 12. Batista MJ, Lawrence HP, Sousa MDLR. Oral health literacy and
oral health outcomes in an adult population in Brazil. BMC Public
sample size was adequate and achieved a high respon- Health. 2018;18:60.
se rate (93.8%). Self-completed questionnaires avoided 13. Cepova E, Cicvakova M, Kolarcik P, Markovska N, Geckova AM.
any excessive influence of an interviewer, who was only Associations of multidimensional health literacy with reported oral
present to clear up any queries about how to complete health promoting behaviour among Slovak adults: a cross-sectional
study. BMC Oral Health. 2018;18:44.
the questionnaire correctly. 14. Atchison KA, Macek MD, Markovic D. The value of a combined
word recognition and knowledge measure to understand characteris-
Conclusions tics of our patients’ oral health literacy. Community Dent Oral Epide-
As a general conclusion it may be stated that there is an miol. 2017;45:380-8.
15. McQuistan MR, Qasim A, Shao C, Straub-Morarend CL, Macek
association between the educational level of the adult MD. Oral health knowledge among elderly patients. J Am Dent Assoc.
population studied and levels of oral health knowled- 2015;146:17-26.
ge; as the educational level of the subjects increased so 16. Ho MH, Liu MF, Chang CC. [A Preliminary Study on the Oral
did their oral health knowledge. Subjects aged over 55 Health Literacy and Related Factors of Community Mid-Aged and Ol-
der Adults]. Hu Li Za Zhi. 2019;66:38-47.
years presented a lower level of oral health knowledge; 17. Mohammadi TM, Malekmohammadi M, Hajizamani HR, Mahani
as age increased mean scores for oral health knowledge SA. Oral health literacy and its determinants among adults in Sou-
decreased. Women showed a higher level of oral health theast Iran. Eur J Dent. 2018;12:439-42.
knowledge than men, particularly in the domains chil- 18. Jones M, Lee JY, Rozier RG. Oral health literacy among adult pa-
tients seeking dental care. J Am Dent Assoc. 2007;138:1199-208; quiz
dren`s oral health, disease and prevention, and periodon- 1266-7.
tal disease. An association exists between oral quality 19. Sistani MMN, Yazdani R, Virtanen J, Pakdaman A, Murtomaa H.
of life and level of oral health knowledge. Subjects re- Oral health literacy and information sources among adults in Tehran,
porting difficulty chewing food, problems with speaking Iran. Community Dent Health. 2013;30:178-82.
20. Bellamy Ortiz C.l MAA. The relationship between oral heal-
and pronunciation, felt concerned with the state of their th- related to quality of life, tooth loss and removable prostheses in
teeth, avoided smiling, took time off work or experien- IMSS beneficiaries adults over the age of 50. Av Odontoestomatol.
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Acknowledgments
low level of oral health knowledge. The authors received financial support from the “Ministry of Educa-
tion for obtaining the Collaboration Scholarship in University Depart-
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