The relationship between knowledge of
oral health-related issues and the DMFT index in 12-year-old students in
Rafsanjan, Iran, in 2016
Shakerian
M, MD1*, Sardari F, MD2, Kordafshari T3
1- Assistant Prof.,
Dept. of Operative Dentistry, School of Dentistry, Rafsanjan University of
Medical Sciences, Rafsanjan, Iran. 2- Assistant Prof., Dept. of Oral Medicine,
School of Dentistry, Rafsanjan University of Medical Sciences, Rafsanjan, Iran.
3-Assistant Prof., Dept. of Operative Dentistry, School of Dentistry, Golestan University
of Medical Sciences, Golestan, Iran.
Abstract Received:
September 2016, Accepted:
October 2016
|
Background: Children are the most
sensitive and vulnerable group in terms of tooth decay. Any change or
improvement in health-related knowledge and behavior in this group can have
long-term and significant impacts on the health of the future generation.
Thus, the present study was conducted with the aim to determine the
relationship of knowledge of oral health-related issues with the decayed,
missing, and filled teeth (DMFT) index in 12-year-old students of Rafsanjan,
Iran, in 2016. Materials
and Methods:
This descriptive, cross-sectional study was performed on 460 students (230
boys and 230 girls) of 12 years of age from 10 elementary schools in
Rafsanjan. The subjects were randomly selected. Data were collected through
clinical examination, interviews, and a questionnaire. The questionnaire
consisted of two parts; the first part contained a demographic
characteristics form, and the second part contained the DMFT index and
questions on knowledge of oral health-related issues. Data were analyzed
using independent t-test, ANOVA, chi-square, and the Pearson correlation
coefficient (α = 0.05). Results: Mean DMFT index and knowledge
score of the students were 2.66 ± 1.40 and 5.43 ± 1.82, respectively.
Students with higher knowledge had lower DMFT index. Moreover, mean knowledge
score of students with homemaker mothers was significantly higher compared to
students with working mothers. Conclusion: The results of this study
suggested a positive significant relationship between knowledge of oral
health-related issues and DMFT index in 12-year-old students of Rafsanjan. |
Keywords: Knowledge, Oral Hygiene,
Awareness, Dental Caries
Introduction
Tooth decay is a
bacterial disease of calcified dental tissues which causes the demineralization
of inorganic matter and destruction of organic matter. Factors which cause
tooth decay can be divided into 3 groups related to the host (saliva,
composition, and tooth structure), environmental factors (nutrition and
fluoride) and microorganisms (1). Tooth decay, as a multifactorial bacterial
disease, is greatly affected by other factors such as parental education,
family economic status, number of family members, and level of oral hygiene maintenance
(2). Oral hygiene has obtained much attention in regards* to provision
and improvement of public health to the extent that it is now recognized as one
of the main 11 slogans of the 21st century (3). On the other hand,
correct understanding of the oral status and treatment needs of different age
groups is one of the most important factors in health-treatment planning. Today,
correct and accurate information comparable to international standards attract
the attention of researchers and planners. The determination of different
indices related to oral health status in different time periods and age and
social groups is necessary to obtain an accurate depiction of the current
situation that can be compared with the objectives of the FDI World Dental
Federation (4). The most important index for the determination of the
prevalence of tooth decay in a population is the decay, missing, and filled
teeth (DMFT) index. To calculate the DMFT of a society, the total number of permanent
decayed, extracted, and filled teeth of each individual in that society is
counted and its mean is calculated. DMFT is a simple, rapid, and quantifiable
index in dentistry which has been used for many decades (5). Determination of
DMFT and other indices enables societies to expand their plans toward the
prevention or treatment of oral diseases. Calculation of indices related to
tooth decay for 12-year-old children is one of the recommendations of the World
Health Organization (WHO). Any change or improvement in health knowledge and
behavior can have long-term and significant impacts on the health of the future
generation. Furthermore, the resulting data is used as foundational statistics
to determine the treatment requirements of the studied society, for unbiased
distribution of health and treatment facilities, and management of dentistry
prevention programs for the development of comprehensive health programs (6).
Sadeghi studied the prevalence of decayed permanent first molar among
12-year-old students in Rafsanjan, Iran, in 2007 (7). He found that mean DMFT
of the permanent first molar was 1.9 ± 1.6, and girls had more decayed teeth
compared to boys (7). Mirzaei et al. conducted a study on the knowledge,
attitude, and action of students of elementary schools in Yazd, Iran, regarding
oral hygiene (8). They concluded that the knowledge, attitude, and action of
students regarding oral hygiene were at an average level. In addition, the
students reported their health coach and teachers as their most important
source of information (8). Peng et al. performed a study with the aim of
describing the oral health status of urban 12-year-old students, evaluating their
behavior and attitudes regarding oral hygiene, and assessing the effect of
socio-economic factors on tooth decay (9). They reported that children living
in the center of a city obtained most of their information on oral hygiene from
dentists and teachers and had a significant difference with children in rural
areas in this respect. However, no significant difference was observed between
boys and girls in this regard (9). The present study was undertaken with the
aim of the evaluation of oral health status and determination of the
relationship of knowledge of oral health-related issues with the DMFT index in
12-year-old students of Rafsanjan in 2016.
Materials and Methods
This descriptive,
cross-sectional study was conducted on 12-year-old students of Rafsanjan. Based
on a similar study (10) and sample volume equation, 460 students (230 girls and
230 boys) were randomly selected as study subjects. All students who were
identified as medically healthy in the preliminary evaluation based on health
records available at the school, were Iranian citizens, and resided in
Rafsanjan were entered into the study. Students with systemic diseases or
mental disorders were eliminated from the study. The participants’ age was
recorded based on date of birth. The data were collected through clinical
examinations, interviews, and a joint questionnaire by the Ministry of Health
and Ministry of Education (11). The questionnaire consisted of two parts. The
first part consisted of demographic characteristics such as gender, education
level, parental occupation, and order of child’s birth. The second part
contained questions on the knowledge of oral health issues, such as brushing,
flossing, and fluoride and cariogenic food use, and information regarding the
DMFT index. To determine tooth decay, the WHO definition was used; destruction
in the form of visible cavities on the smooth surface or grooves of the teeth
and the floor or soft visible wall of tooth enamel. Restored teeth with
recurring caries and teeth filled with temporary material were also included in
this category. Suspicious areas and white spots were not considered as tooth
decay. Missing teeth were only recorded if they were extracted because of
decay; teeth that were extracted due to traumatic or non-traumatic causes such
as orthodontics were not included in this category. Teeth with 1 or more
permanent, intact restorations without caries were recorded as filled teeth.
Regarding proximal surfaces, if the tip of the probe entered the cavity it was
recorded as tooth decay, if there was any doubt, it was considered as a healthy
tooth (7). To determine the level of knowledge of the subjects, their correct
responses to questionnaire items (10 questions) received 1 point and incorrect
responses received 0 points. Total knowledge score of less than 5 demonstrated
poor knowledge, 5-7 average knowledge, and higher than 7 good knowledge. Data
were analyzed in SPSS software (version 23, SPSS Inc., Chicago, IL, USA), and
results of quantitative variables was presented as mean ± SD and qualitative
variables as number (%). Mean dental parameters were compared using independent
t-test and ANOVA, and qualitative variables were compared using chi-square
test. The Pearson correlation coefficient was used to determine the
relationship between students’ knowledge score and DMFT index. Significant
level was determined as less than or equal to 0.05 in all tests.
Results
Mean total DMFT
index of students was 2.66 ± 1.40 and mean DMFT index of boys and girls was,
respectively, 2.61 ± 1.35 and 2.71 ± 1.45 (P= 0.443) (Table 1).
Table 1:
Prevalence of decayed, missing, and filled teethý index
and its components (decayed, extracted, and restored permanent teeth) among
12-year-old students of Rafsanjan in 2016
|
Index Gender |
Decay |
Extracted |
Restored |
DMFT |
|
Mean ± SD |
||||
|
Boys |
1.38±0.90 53% |
0.47±0.63 18% |
0.76±0.69 29% |
2.61±1.35 |
|
Girls |
1.27±0.94 46% |
0.38±0.53 15% |
1.06±0.84 39% |
2.71±1.45 |
|
total |
1.33±0.92 50% |
0.43±0.58 16% |
0.90±0.78 34% |
2.66±1.40 |
|
P |
0.223 |
0.094 |
0.001 |
0.443 |
DMFT:
decay, missing, and filled teeth
The results of the
study showed that mean total knowledge score of students was 5.43 ± 1.82 and its
mean among boys and girls was, respectively, 4.50 ± 1.61 and 6.37 ± 1.52. Mean
knowledge score was significantly higher among girls compared to boys (P <
0.001).
The results of
students’ knowledge score with consideration of their parents’ educational and
occupational status showed that the mean knowledge score of students with
homemaker mothers was significantly higher than students with working mothers
(P = 0.009). No significant difference was observed in other related items (father’s
and mother’s education and father’s occupation) (P < 0.050).
The results of the
comparison of the DMFT index in each subgroup of poor, average, and high
knowledge are presented in table 2. The results presented in this table show
that students with higher knowledge had lower DMFT index and students with
lower knowledge had higher DMFT index. The comparison of boys and girls
illustrated that girls had significantly better performance (P < 0.001).
Table 2:
Mean decayed, missing, and filled teethý index based on
knowledge score among 12-yearl-old students in Rafsanjan in 2016
|
Knowledge DMFT |
Poor |
Average |
High |
P-Value |
|
Mean ± SD |
||||
|
Boys |
2.83±1.47 |
2.46±1.14 |
1.73±1.27 |
0.009 |
|
Girls |
3.04±1.61 |
2.87±1.31 |
2.09±1.58 |
0.001 |
|
Total |
2.87±1.49 |
2.71±1.26 |
2.03±1.53 |
0.001 |
DMFT:
decay, missing, and filled teeth
Based on the
results of table 3, although the students’ knowledge score increased with
increase in mothers’ education level, this relationship was not statistically
significant (P = 0.117). Furthermore, with increase in order of birth, the
students’ knowledge score decreased; students with higher birth order had lower
knowledge scores (P = 0.001).
Table 3:
The Pearson correlation coefficient of qualitative variables and knowledge score
of 12-year-old students of Rafsanjan in 2016
|
|
Fathers’
education |
Mothers’
education |
Birth
order of the student |
|
|
Knowledge
score (poor, average, high) |
rs |
-
0.029 |
0.075 |
-
0.153 |
|
P-value |
0.542 |
0.116 |
0.001 |
|
*
Correlation significant at 0.01 level
Discussion
Today, oral
hygiene is a necessity and part of public health, and failure to maintain
dental hygiene results in dental issues, disruption of public health, reduced
self-esteem, chronic infections, and reduced quality of life (QOL), especially
in children. Thus, this issue is a priority of the WHO in its chronic diseases
prevention and health promotion programs (12, 13). The 6-12 years age group is
prioritized in oral hygiene programs due to the high prevalence of tooth decay
in this group, and the importance of this age group in terms of development of
permanent teeth and formation of beliefs, habits, and lifestyle. Any change or
improvement in the behavior of this age group can have long-term and
significant impacts on the health of the future generation of the society. Some
researchers believe that increased knowledge and awareness in this age group is
the only method of oral hygiene improvement in the society. Furthermore, the
simplest and most cost-effective method of implementing awareness and knowledge
promotion programs is to execute them in schools (14-17).
Based on the
results of the present study, students with higher knowledge level had lower
DMFT index. The separation of gender groups proved this relationship to be also
significant among both boys and girls. The study by Gauba et al. on 100
students of 10-12 years of age in India showed knowledge to be significantly
correlated with performance, plaque index, gingival health, and tooth decay
expansion rate after educational and treatment intervention (18). They found
that knowledge level and tooth brushing behavior had increased and use of
sugar, plaque index, gingival inflammation, and tooth decay expansion rate had
decreased after their intervention (18). Lalic, in a study on 112 Serbian
students of 12 years of age, found that mean decayed teeth decreased and mean
restored teeth increased 6 months after the educational intervention (19).
Moreover, this study showed that education increased motivation for self-care
among students which, in turn, increases the oral health level (19).
The results of the
present study showed that students’ knowledge score with consideration of
parents’ occupational and educational status showed that this score was
significantly higher among students with homemaker mothers compared to those
with educated and working mothers. No significant difference was observed in
other cases in this respect. Numerous studies have illustrated the role of parents
in the prevention of oral diseases in their children. Poutanen et al. reported
a significant relationship between parents’ health behavior and their
children’s health behavior (20). The results of the study by Saied Mohammadi et
al. also showed lower rate of tooth decay among children of mothers who
maintained oral hygiene (21). Mitrankul et al. also reported parents’ education
level as an effective factor in their children’s oral health (22). Costa
believed that to ensure adequate oral health, parents’ views of their
children’s health habits are important (23). Thus, it is evident that oral
health hygiene and knowledge of parents has a positive impact on their
children’s oral health, and their knowledge and attitude regarding oral health
can promote their children’s oral health skills (24).
The current study
results also showed that knowledge of oral health-related issues had an inverse
relationship with birth order; with increase in birth order, knowledge score
decreased. This finding was in agreement with that of the study by Javadinejad
et al. who showed that with increase in the number of children in a family, the
prevalence of tooth decay also increased (6). Increased birth order which is
also indicative of increase in the number of family members can decrease the
contribution of household income and parents’ attention to each member (6).
Overcoming
problems such as time limitation, high costs, and want of facilities and
equipment is a barrier to oral treatments. The most important way to decrease
and prevent oral diseases (25, 26) and the most important solution in this
respect is the implementation of interventions related to health promotion and
educational programs aiming at increasing students’ knowledge (27). Application
of different health education solutions based on novel learning methods and use
of the most effective and rapid method for the promotion of oral health in
children is of great importance. Through these methods, the rate of oral
diseases can be decreased in this age group. In this respect, numerous studies
have shown that, despite the many methods and patterns used in the execution of
oral health promotion interventions in different countries, the most important
principle of education and promotion of knowledge in order to reduce oral
diseases is the consideration of lifestyle-related behavior (28-30). Lack of
knowledge on oral health, maintenance of hygiene, and prevention of oral
diseases will result in the loss of teeth at younger ages and more difficult
and costly future outcomes. Lack of preventive measures, expansion of oral
health services, and education on oral health in these children will result in
the payment of high treatment costs, and provision of dental materials and
expensive equipment and human resources in oral treatments by families and the
government (31, 32).
Conclusion
The results of the
present study suggested the presence of a significant relationship between
knowledge of oral health issues and DMFT index in 12-year-old students of
Rafsanjan. High rate of knowledge can have a positive effect on the health
behavior of students, and these health behaviors are effective on oral health.
Acknowledgement
The authors wish
to thank Dr. Mostafa Sadeghi for his valuable advice.
Conflict of interest: None
declared
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* Corresponding author: Mohadeseh
Shakerian,
Dept of Operative Dentistry, School of Dentistry, Rafsanjan University of
Medical Sciences, Rafsanjan, Iran.
E-mail: m.shakerian@rums.ac.ir