|Year : 2021 | Volume
| Issue : 2 | Page : 134-139
Intelligence quotient and dental caries: An analytical cross-sectional study among Saudi Arabian Children
Ghada Mohammed Madhan, Rafi Ahmad Togoo, Maha Abdulaziz Abumelha, Manal Nasser AlJahdal, Zuhair Motlak Alkahtani, Tasneem Sakinatul Ain
Division of Preventive Dentistry, Department of Pediatric Dentistry and Orthodontic Sciences, King Khalid University College of Dentistry, Abha, Kingdom of Saudi Arabia
|Date of Submission||28-Aug-2021|
|Date of Decision||12-Sep-2021|
|Date of Acceptance||24-Sep-2021|
|Date of Web Publication||10-Dec-2021|
Dr. Tasneem Sakinatul Ain
Division of Preventive Dentistry, King Khalid University College of Dentistry, Abha
Kingdom of Saudi Arabia
Source of Support: None, Conflict of Interest: None
Context: Dental caries have a detrimental impact on the affected persons, be they children, adolescents, or adults. Aim: To find out the prevalence of dental caries and its relationship with intelligence quotient (IQ) among Southern Saudi Arabian children. Settings and Design: A nonprobability convenience sampling procedure was adopted. Methods: As much as 458 eligible children were selected for the study. Estimation of level of IQ was done by using “Raven's Coloured Progressive Matrices 1998 edition 11.” DMFT/ dmft index was used to assess the prevalence of dental caries among the participants. Statictics used: The collected data were subjected to statistical analysis using Statistical Package for Social Sciences Version 22. Frequencies, percentages, mean, and SDs were applied to report the caries prevalence. Chi-square test and unpaired t-test were applied to test the association between two categorical variables. P valueslessthan 0.05 were considered statistically significant. Results: The prevalence of dental caries was 52.62% with mean total DMFT of 1.48 ± 1.93. Prevalence of primary dmft was 80.13% with mean dmft of 4.60 ± 3.67. The presence of dental caries among primary teeth was statistically significant according to the IQ. Conclusion: The prevalence of dental caries was found to be 52.62% for permanent teeth and 80.13% for primary teeth. The IQ of most children falls under the Grade III category of Raven's Coloured Progressive Matrices grading system. The current study revealed an inversely proportional relationship between IQ grade and the prevalence of dental caries.
Keywords: Child, dental caries, intelligence, prevalence
|How to cite this article:|
Madhan GM, Togoo RA, Abumelha MA, AlJahdal MN, Alkahtani ZM, Ain TS. Intelligence quotient and dental caries: An analytical cross-sectional study among Saudi Arabian Children. Niger J Basic Clin Sci 2021;18:134-9
|How to cite this URL:|
Madhan GM, Togoo RA, Abumelha MA, AlJahdal MN, Alkahtani ZM, Ain TS. Intelligence quotient and dental caries: An analytical cross-sectional study among Saudi Arabian Children. Niger J Basic Clin Sci [serial online] 2021 [cited 2022 Jan 17];18:134-9. Available from: https://www.njbcs.net/text.asp?2021/18/2/134/332196
| Introduction|| |
Dental caries is categorized as one of the highly prevalent, most common oral diseases worldwide. World Health Organization reports reflect that 60–90% of school children, in both the developed and the developing countries, are affected by dental caries., Dental caries have a detrimental impact on the affected persons, be they children, adolescents, or adults. It not only affects the individual's health, but also has a considerable bearing on his/her social, psychological, and economic aspects of life, thereby affecting his/her overall quality of life as well. Among the children, also missing regular school days/classes have been observed because of the consequences of dental caries.
Intelligence quotient (IQ) and dental caries have a bi-directional relationship, in a real sense. The lower IQ may reduce the cognitive understanding regarding the preventive measures and maintenance of oral hygiene among such children, and hence they become more prone to having dental caries. Moreover, the high prevalence and severity of dental caries in a child results in lowering his/her confidence and social interaction, including skipping the school days, and hence it tells upon his/her psychology, thereby reducing his/her intellectual and cognitive development. Pain, discomfort, unattractive smile, impaired speech, and abnormal eating habits are the adverse consequences of untreated dental caries which ultimately have a negative impact on children's quality of life owing to the psychosocial problems caused by way of reduced interpersonal relationships and self-esteem among them.
Previous research has emphasized the role of psychosocial factors in understanding the process of dental caries progression and improving its risk prediction. Earlier studies conducted to assess the relationship between IQ and dental caries show variations in the results., As observed in a British Cohort research, more intelligent children grew up as adults practicing good dietary habits, suggesting that intelligence might play an essential role in ensuring oral health through life.
With this backdrop, a study was carried out to find out the prevalence of dental caries and its relationship with IQ among Southern Saudi Arabian children.
| Materials and Method|| |
A cross-sectional observational study was carried out among 7–12 years old children at public schools of, Saudi Arabia during the period from July 2019 to December 2019. A nonprobability convenience sampling procedure was adopted wherein 458 eligible children were selected for the study. Before the start of the study, informed consent was obtained from the parents/guardians of the children through school authorities. Ethical approval was given by the Scientific Review Committee King Khalid University College of Dentistry (IRB/reg/2019-2020/38IRB).
Children having no history of disease/trauma in the head and neck region, no developmental disorder/problems, and children who were residents of Saudi Arabia and physically and mentally fit were included in the study. Children suffering from any congenital/acquired disease affecting the cognitive/intelligence capability and those having any systemic problems or under medications (such as those taken for depression) were excluded from the study.
DMFT/dmft index was used to assess the prevalence of dental caries among the participants. The oral examination of children was conducted in respective classrooms under natural light using a mouth mirror and explorer by two examiners (GMM and MAA). An adequate number of sterilized instruments were made available during the survey at schools and current recommendations and standards for infection control were followed. Estimation of level of IQ was done by examiner (MNA) using “Raven's Coloured Progressive Matrices 1998 edition 11.”, A total of 36 problems were included in the test, divided into three segments. The test is a nonverbal test form; questions were framed in a geometrical pattern, with a section missing. Participants were asked to choose the missing cell from the six given choices and were given a test form and requested to answer every one of the inquiries in the, particularly composed answer paper. Participants were also given 30 min time to complete the test as per the test manual's guidelines. The acquired data were changed over into percentile, and the assessment of overall score was graded according to the Raven's Coloured Progressive Matrices (CPM) manual:
- Grade I: “Intellectually superior,” if a score lies at or above the 95th percentile for people of that age group.
- Grade II: “Definitely above the average in intellectual capacity,” if a score lies at or above the 75th percentile.
- Grade III: “Intellectually average,” if a score lies between the 25th and 75th percentiles.
- Grade IV: “Definitely below average in intellectual capacity” if a score lies at or below the 25th percentile.
- Grade V: “Intellectually impaired,” if a score lies at or below the 5th percentile for that age group.
Two examiners were trained and calibrated in the dental clinics of ############ by experienced faculty members for the assessment of dental caries and IQ with 15 subjects for two successive days and the intra-examiner and inter-examiner reliability was found to be satisfactory (0.97 and 0.85, respectively) when assessed by Cronbach's alpha. After clinical examination of the study subjects, they were referred to ############ for immediate treatment and were also educated regarding the maintenance of oral hygiene and the importance of periodic dental visits and good oral health.
The collected data were entered into the computer (MS-Office, Excel), after which was subjected to statistical analysis using Statistical Package for Social Sciences Version 22.0 software (IBM, Armonk, NY, USA). Frequencies, percentages, mean, and SDs were applied to report the caries prevalence. Chi-square test and unpaired t-test were applied to test the association between two categorical variables. P values less than 0.05 were considered statistically significant.
| Results|| |
A total of 458 children participated in the present study of which 209 (45.6%) were male and 249 (54.4%) female. Two hundred fifty (54.6%) comprised of 7–9 years old subjects, whereas 208 (45.4%) were 10–12 years old.
The prevalence of dental caries was 52.62% with mean total DMFT of 1.48 ± 1.93 [Table 1].
|Table 1: Total number and mean scores of permanent DMFT among participants|
Click here to view
The mean total dmft was 4.60 ± 3.67. Prevalence of primary dmft was 80.13% among participants [Table 2]. [Table 3] shows participants' distribution according to the Raven's CPM grading. The mean score percentage of IQ was 64.29 ± 18.19. Most participants' scores fell under the Grade III criteria among the Raven's CPM grading system (n = 315, 68.8%), with a third of participants' scores under Grade II (n = 134, 29.3%). The presence of dental caries among primary teeth was statistically significant according to the IQ (P < 0.0001) [Table 4].
|Table 2: Total number and mean scores of primary dmft among participants|
Click here to view
|Table 3: Participants' distribution according to Raven's Coloured Progressive Matrices grading|
Click here to view
|Table 4: Association of primary teeth dental caries with intelligence quotient among participants|
Click here to view
[Table 5] shows the association of permanent teeth dental caries with IQ among participants. The association was statistically nonsignificant.
|Table 5: Association of permanent teeth dental caries with intelligence quotient among participants|
Click here to view
On comparing the association of dental caries in primary teeth based on gender, a nonsignificant difference was found [Table 6]. The association was not statistically significant. [Table 7] shows the association of permanent teeth dental caries with gender among participants. The presence of dental caries among permanent teeth was statistically significant according to gender (P = 0.009). A statistically nonsignificant association was observed when IQ was compared based on gender [Table 8].
|Table 6: Association of primary teeth dental caries with gender among participants|
Click here to view
|Table 7: Association of permanent teeth dental caries with gender among participants|
Click here to view
|Table 8: Association of gender with intelligence quotient of study participants|
Click here to view
| Discussion|| |
Intelligence is the ability of the mind to solve problems, reason, think, learn, use linguistic skills, and comprehend ideas. Intelligence is unique to every individual, and it can be assessed using IQ. Well defined by Wechsler, intelligence is the ability of an individual to adapt and to solve problems in the environment constructively. However, IQ is defined as the relative intelligence of an individual expressed as a score on a standardized calibration of intelligence.
The focus on excessive sugars as etiology for dental caries has been shifted to a much complex interaction of genetic and environmental factors involving biological, behavioral, social, and psychological elements. A person's behavior is influenced by his/her psychology and cognitive skills, which in turn is related to his/her IQ.
Through quite a few studies exploring the relationship between dental caries and IQ of young children, the oral health status of children has been inferred to be associated with IQ, thus, in furtherance hereof, the current study has been carried out to assess the prevalence of dental caries and its correlation with IQ among children of Southern Saudi Arabia.
In the current study, the prevalence of dental caries was found to be 52.62%, with a mean DMFT of 1.48 ± 1.93 for permanent teeth and a mean dmft of 4.60 ± 3.67 for primary teeth. The prevalence of dental caries in the case of the primary teeth of children arrived at 80.13%. The dental caries prevalence in cases of permanent and primary teeth of children in our study was seen to be slightly higher than that reported in a previous study conducted with the same age group wherein it was found as 75.3% and 42.1%, respectively. The mean DMFT/dmft in the current study is according to the previous reports by Khan et al. in a review of literature on dental caries in Arab League countries wherein the mean DMFT of permanent dentition was 1.77 and the mean dmft of the primary was reported to be 4.34. In yet another study at Abha, Saudi Arabia, a prevalence of 85.4% was reported among 6–13 years old children.
To assess the status of IQ among the children, Raven's CPM grading system was used. There are various other IQ measurement tests, such as Differential Ability Scales, Sternberg Triarchic test, Cognitive Assessment System, Wechsler Intelligence Scale, and Turing Test. Raven's CPM test has been universally accepted as a nonverbal intelligence test for young children. As a screening tool, it is easily administered, cost-effective, flexible, and labor-saving that measures the analytical intelligence and mental development of young children.
Most participants' scores fell under the Grade III criteria of the Raven's CPM grading system (n = 315, 68.8%), with a third of participants' scores under Grade II (n = 134, 29.3%). In simpler words, we can say that majority of study subjects were intellectually having average grades, followed by those with above-average scores for IQ. The occurrence of dental caries in primary teeth was found to be statistically significant (P < 0.0001) when compared based on different grades of IQ, whereas the prevalence of dental caries was 73.3% among children with IQ of Grade III level, and it was 0.8% in those with IQ of Grade I status. However, different findings were reported by Dhanu et al. (2019), where the majority of the children had intellectually disabled scores (47.1% – Grade V), followed by those having definitely below-average intellectual capacity scores (35.4% – Grade IV). The difference in study settings, sample sizes, and population ratio, and the difference in measurement tools may account for the variance in the results.
In the current study, the presence of dental caries among primary teeth was observed to be 57% among children having average IQ scores, whereas it was 0.7% among children with high IQ scores, and the difference was found to be statistically significant when compared based on IQ (P < 0.0001). These findings were in parity with the findings of Shanker et al. and Steinberg and Zimmerman, stated: the higher the IQ level, the higher caries score and that the lower IQ group was acquiring cavities at a faster rate than the higher IQ group. Several studies also supported similar findings: Kallestal et al. associated high IQ with oral health and concluded that poor health behavior was related to low self-esteem, while Manhold and Rosenberg also supported the hypothesis that a weak personality was associated with dental decay. Moreover, findings by Ozaki et al. stated that the relationship between the increase of dental caries and personality characteristics corresponded to a low degree of direct correlation. Oral health and related behavior have been associated with numerous psychological factors such as IQ, anxiety, self-esteem, and personality aspect, in a previously conducted research by Dumetrisecu et al.
Oral health behaviors like maintaining oral hygiene, following the instructions given by dentists, and cooperating in dental settings while undergoing dental treatment, and also being able to communicate and respond well during counseling are all directly related to the cognitive skills of the patients (children in current topic) which are developed due to IQ. A strong association has been found between the dental anxieties of a child to his/her intelligence which would affect the level of compliance and acceptance while undergoing dental treatment. Understanding of information, instructions, causes and effects, and expressing feelings of pain or relief from pain; all these characteristics of children are significantly dependent on their intelligence. Less dental visits, poor plaque control, and inadequate oral health beliefs were found in children with lower IQ when compared with those having high IQ, as established in a study by Thomson et al. (2019) that supports the findings of more dental caries prevalence among those with lower IQ.
However, contradictory findings were reported in several studies conducted previously on different population strata and study settings using different IQ testing scales. A nonsignificant association between DMFT and IQ was reported among 10–15 years old children by Navit et al. (2014). However, they found a statistically significant correlation between IQ and gingivitis. Dental caries is a multifactorial disease; there may be other numerous factors affecting the outcome of various research works because it is not possible to control or take into account all such factors and hence attributed to the variation in the findings of previously conducted studies which aimed to find the association of IQ and dental caries.
It is noteworthy to mention here that intelligence is related to the self-esteem of a person which is co-dependent on oral health and a healthy smile. Interpersonal relationships and self-esteem build a favorable environment posed by a child's good oral health, especially from the esthetic point of view. Other than pain, discomfort, difficulty in chewing, sleep-disturbance because of the presence of untreated dental caries can have quite detrimental consequences such as those related to smiling, less or no interaction with others, missing school days; all of these eventually result in low self-confidence and negative impact on child's psychology and IQ.,, In the present study, such factors could not be studied to know the bi-directional relationship of dental caries and IQ. However, future studies may explore more factors to get a definitive and more elaborative conclusion regarding various factors playing their significant roles.
Limitations of the study
- Random sampling with a larger sample size would yield better results.
- Various other factors related to dental caries such as socioeconomic factors, methods of maintaining oral hygiene, and dietary habits could not be explored because of time constraints.
| Conclusion|| |
In the current study, the prevalence of dental caries was found to be 52.62% with a mean DMFT of 1.48 ± 1.93 for permanent teeth and a mean dmft of 4.60 ± 3.67 for primary teeth. In 80.13% of children, the prevalence of dental caries of primary teeth has been found. The IQ of most children falls under the Grade III category of Raven's CPM grading system. The current study revealed an inversely proportional relationship between IQ grade and the prevalence of dental caries.
- Persuasion: Inevitably, the children need to be persuaded to adopt preventive oral health measures and seek dental treatment to augment the retention of natural teeth at an advanced age.
- Health promotion/awareness: Oral health promotion and preventive programs at individual, family, community, and school levels are necessarily required to be put in place.
- Evaluation: Regular evaluation of the ongoing preventive, educative, and curative oral health services at different levels of the healthcare system is required to assess the outcome and to make improvements wherever necessary.
- Collaborative efforts: All oral health professionals, dental public health specialists, pediatric dentists, general practitioners, and medical health professionals need to invest their efforts collaboratively to target a larger population of children, parents, and school teachers for reducing the incidence of dental caries and to live a quality healthy life in terms of robust physical, psychological, and economic futuristic vision.
- Enhanced and sustained research: The scope of advanced research is an essential ingredient for ensuring to arrive at a definitive and more comprehensive understanding of the correlation between IQ and dental caries in particular and overall oral health problems in general.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
World Health Organization: The World Oral Health Report 2003. Continuous improvement of oral health in the 21st
century – The approach of the WHO global oral health programme. Geneva: WHO, 2003.
Petersen PE, Bourgeois D, Ogawa H, Estupinan-Day S, Ndiaye C. The global burden of oral diseases and risks to oral health. Bull World Health Organ 2005;83:661-9.
Dixit LP, Shakya A, Shrestha M, Shrestha A. Dental caries prevalence, oral health knowledge and practice among indigenous Chepang school children of Nepal. BMC Oral Health 2013;13:20.
Peres MA, Latorre MRDO, Sheiham A, Peres KGA, Barros FC, Hernandez PG, et al
. Social and biological early life influences on severity of dental caries in children aged 6 years. Community Dent Oral Epidemiol 2005;33:53-63.
Sabbah W, Sheiham A. The relationships between cognitive ability and dental status in a national sample of USA adults. Intelligence 2010;38:605-10.
Bruckner RJ, Hill TJ. Intelligence quotient and dental caries experience. J Dent Child 1952;19:64-8.
Bonecker M, Abanto J, Tello G, Oliveira LB. Impact of dental caries on preschool children's quality of life: An update. Braz Oral Res 2012;26(Suppl 1):103-7.
Steinberg AD, Zimmerman S. The Lincoln dental caries study. I. The incidence of dental caries in persons with various mental disorders. J Am Dent Assoc 1967;74:1002-7.
Der G, Batty GD, Deary IJ. The association between IQ in adolescence and a range of health outcomes at 40 in the 1979 US National Longitudinal Study of Youth. Intelligence 2009;37:573-80.
Li Y, Jing X, Chen D, Lin L, Wang Z. Effects of endemic fluoride poisoning on the intellectual development of children in Baotou. Chin J Public Health Manage 2003;19:337-8.
Kargul B, Caglar E, Tanboga I. History of water fluoridation. J Clin Pediatr Dent 2003;27:213-7.
Wayne S, Charles M, Robert R, Warren Z, Sharon K, Tiina U. Stanford-Binet and WAIS IQ differences and their implications for adults with intellectual disability. Intelligence 2010;38:242-8.
Fisher-Owens SA, Gansky SA, Platt LJ, Weintraub JA, Soobader MJ, Bramlett MD, et al
. Influences on children's oral health: A conceptual model. Pediatrics 2007;120:510-20.
Satpathy M. Psychological tests developed for children in India: A review of recent trends in research, practice and application. In: Shyam R, Khan A, editors. Clinical Child Psychology. 1st
ed. New Delhi: Kalpaz Publication; 2009. p. 275-92.
Ramsden S, Richardson FM, Josse G, Thomas MS, Ellis C, Shakeshaft C, et al
. Verbal and non-verbal intelligence changes in the teenage brain. Nature 2011;479:113-6.
Youssefi MA, Afroughi S. Prevalence and associated factors of dental caries in primary school children: An Iranian setting. International Journal of Dentistry 2020:8731486. doi: 10.1155/2020/8731486.
Khan SQ. Dental caries in Arab League countries: a systematic review and meta-analysis. Int Dent J 2014;64(4):173-80.
Abolfotouh MA, Hassan KH, Khattab MS, Youssef RM, Sadek A, El-Sebaiei M. Dental caries: Experience in relation to wasting and stunted growth among schoolboys in Abha, Saudi Arabia. Ann Saudi Med 2000;20;360-3.
Dhanu G, Havale R, Shrutha SP, Quazi N, Shafna TP, Ahemd A. Assessment of intelligence quotient using Raven's coloured progressive matrices among school children of Hyderabad Karnataka region and its correlation with prevalence of dental caries. J Indian Soc Pedod Prev Dent 2019;37:25-30.
] [Full text]
Raven JC, Court JH, Raven JC. Manual for Raven's Progressive Matrices and Vocabulary Scales - Section 2: Coloured Progressive Matrices. Oxford: Oxford Psychologists Press; 1990.
Shanker B, Tewari A, Jain RL, Verma SK. A study of prevalence and severity of dental caries in children of different intelligence quotient levels. J Indian Dent Assoc 1983;55:413-7.
Kallestal C, Dahlgren L, Stenlund H. Oral health behaviour and self esteem in Swedish children. Soc Sci Med 2000;51:1841-9.
Manhold JH, Rosenberg N. Study of possible relationship of personality variables to dental cavities. J Dent Res 1954;33:357-63.
Ozaki M, Ishii K, Kuboyama H, Ozaki Y, Motokawa W. An epidemiological study on dental caries of children in the town of Fuji 3. Correlation between dental caries and personality characteristics. Shoni Shikagaku Zasshi 1991;29:62-71.
Dumetrisecu A, Dogaru BC, Dogaru CC. Instability of self esteem and affective liability as determinants of self reported oral health status and oral health related behaviours. J Contemp Dent Pract 2008;9:38-45.
Kumar S, Sharma J, Duraiswamy P, Kulkarni S. Determinants for oral hygiene and periodontal status among mentally disabled children and adolescents. J Indian Soc Pedod Prev Dent 2009;29:46-51.
Rud B, Kisling E. The influence of mental development on children's acceptance of dental treatment. Scand J Dent Res 1973;81:343-52.
Thomson WM, Broadbent JM, Caspi A, Poulton R, Moffitt TE. Childhood IQ predicts age-38 oral disease experience and service-use
. Community Dent Oral Epidemiol 2019;47:252–8.
Navit S. Interrelationship of intelligence quotient with caries and gingivitis. J Int Oral Health 2014;6:56-62.
Rebok G, Riley A, Forrest C, Starfield B, Green B, Robertson J, et al
. Elementary school-aged children's reports of their health: A cognitive interviewing study. Qual Life Res 2001;10:59-70.
Feitosa S, Colares V, Pinkham J. The psychosocial effects of severe caries in 4-year-old children in Recife, Pernambuco, Brazil. Cad Saude Publica 2005;21:1550-6.
Filstrup SL, Briskie D, Fonseca M, Lawrence L, Wandera A, Inglehart MR. Early childhood caries and quality of life: Child and parent perspectives. Pediatr Dent 2003;25:431-40.
Oliveira LB, Sheiham A, Bonecker M. Exploring the association of dental caries with social factors and nutritional status in Brazilian preschool children. Eur J Oral Sci 2008;116:37-43.
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7], [Table 8]