Associated Factors of Dental Caries among Intellectually Disabled Persons in Specialized Centers of Ouagadougou ()
1. Introduction
Studies from diverse geographical regions have contributed to a growing body of evidence indicating that intellectually disabled individuals are at an elevated risk for dental caries due to a complex interplay of factors [1] [2] .
Among factors, we can cite poor oral hygiene, lack of parental support during tooth brushing, limited access to dental care, and socioeconomic determinants [3] [4] [5] . Psychotropic drugs, which are essential for the stabilization of mental disorders, also have side effects on the oral sphere. The most well-known are the disturbance of salivary function and the increased risk of caries and periodontal disease [6] .
Unfortunately, Burkina Faso does not have recent information on the subject. The objective of this study was to identify the factors associated with it among people with intellectual disability in specialized centers in Ouagadougou, Burkina Faso.
2. Methods
2.1. Ethical and Regulatory Aspects
The research received:
• Approval from the Ministry of Health’s research ethics committee.
• Consent from the Ministry of Women, National Solidarity, Family, and Humanitarian Action’s Central Regional Directorate.
• Permission from the administrators of facilities for individuals with intellectual disabilities.
The study ensured voluntary participation, with the aims of the research being clearly communicated to parents or legal guardians of participants. It also maintained the anonymity and confidentiality of participant information.
2.2. Study Design, Period and Population
It was a cross-sectional study with descriptive and analytical purposes. The survey took place from November 2, 2020, to January 22, 2021, in Ouagadougou, at specialized centers subsidized by the Ministry of Women, National Solidarity, Family and Humanitarian Action. Participation was restricted to those who consented and had guardian approval, excluding individuals unable to open their mouths or lacking independence. A full count of eligible participants was performed.
2.3. Data Collection
The primary method for data collection was a questionnaire adapted from the WHO’s recommendations for oral health surveys [7] . Data gathering employed strategies including accessing information from reception centers (like medical histories) and conducting face-to-face interviews accompanied by clinical assessments. The event of interest in our study was the presence of dental caries measured by the DMF index (Decayed, Missing, or Filled teeth), a widely recognized measure for evaluating oral health globally [7] [8] . Additional data on socio-demographic details, medical and dental backgrounds, oral hygiene practices, and dietary patterns were also compiled.
2.4. Reproducibility and Quality Control
Before the study commenced, interviewers received training on both the methodology and the data collection tools. Calibration of the two dentist examiners was performed against both a standard examiner and each other, with a minimum of 2 days between re-examinations in a subset of 20 individuals, achieving a Cohen’s Kappa coefficient of at least 0.80 for reliability. A preliminary test of the questionnaire was conducted on 20 individuals with intellectual disabilities at a center not included in the study, to refine data collection procedures.
2.5. Statistical Methods
After the collection, the data were entered with the EPIDATA software via a mask created specifically according to the questionnaire used. The data were then transferred to an analysis software STATA MP 16.0 (College Station, Texas 77845, USA). After viewing the data set, some variables were recorded.
The calculation of the DMF was done by adding the three components. The percentage of students with DMF > 0 was used as the prevalence of dental caries. The average DMF is determined by putting the total number of DMF teeth in the numerator and the total number of examinees in the denominator.
Means and their standard deviations were calculated for normally distributed quantitative variables. Frequencies were calculated for all categorical variables of interest.
Binary logistic regression was performed to investigate the association between dental caries and the associated factors. The results of the analysis were expressed as odds ratios and 95% confidence intervals. Values of p < 0.05 were considered statistically significant in all tests.
3. Results
3.1. Carie Prevalence
The overall prevalence of caries was 58.6% with 95% CI [51.2 - 65.8]. The average DMF index was 2.7 ± 3.7 and was broken down as follows: 485 decayed teeth (D), 10 teeth missing due to caries (M) and 4 filled teeth (F).
3.2. Associated Factors of Dental Caries: Univariate Logistic Regression Modeling
3.2.1. Association between Dental Caries and Socio-Demographic Characteristics
Table 1 presents the sociodemographic characteristics associated with dental caries in univariate analysis.
Fathers’ occupation, primary education level and mothers’ “self-employed” occupation were significantly associated with dental caries (p < 0.05)
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Table 1. Socio-demographic characteristics associated with dental caries in univariate analysis.
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Table 2. Medical history associated with caries in univariate analysis.
3.2.2. Association between Dental Caries and Medical History
The table above (Table 2) presents the medical history associated with poor oral health-related quality of life in univariate analysis.
We noted a significant association between caries and severe and profound degrees of intellectual disability (p = 0.033).
3.2.3. Association between Dental Caries and Oral Habits
The table below (Table 3) presents the oral habits associated with dental caries in univariate analysis. There was no significant association between history of pain, frequency and reason for visiting the dentist, frequency of brushing, use of toothpaste, use of fluoridated toothpaste and brushing instruments (toothbrush, dental floss) and dental caries (p > 0.05).
3.2.4. Association between Dental Caries and Eating Habits
Table 4 presents dietary habits associated with dental caries in univariate analysis. No significant association between dietary habits and dental caries was found (p > 0.05).
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Table 3. Oral habits associated with dental caries in univariate analysis.
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Table 4. Dietary habits associated with dental caries in univariate analysis.
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Table 5. Oral pathologies (or functional signs) associated with dental caries caries in univariate analysis.
3.2.5. Association between Dental Caries and Oral Pathologies (or Functional Signs)
The following Table 5 presents the oral pathologies (or functional signs) associated with dental caries. No oral pathology differs significantly from the carious lesion (p > 0.05).
3.3. Associated Factors To Dental Caries: Multivariate Analysis
At univariate analysis, fathers’ occupation, primary education level and mothers’ “independent” occupation were significantly associated with dental caries (p < 0.05). A significant association was noted between caries and degrees of severe and profound intellectual disability (p = 0.033). No significant association between dental history, oral hygiene habits, dietary habits and dental caries (p > 0.05).
After adjustment, factors such as Female gender (OR = 4.16; 95% CI = 1.39 - 12.5, p = 0.01), absence of epilepsy (OR = 3.83; 95% CI = 1.16 - 12.62, p = 0.02), absence of Down syndrome (OR = 5.01; 95% CI = 1.09 - 22.91, p = 0.03), partial motor independence (OR = 0.23; 95% CI = 0.07 - 0.71, p= 0.01), not using toothpaste (OR = 9.33; 95% CI = 1.05 - 82.72, p = 0.04) were significantly associated with dental caries.
Being female is associated with more than four times higher odds of developing dental caries compared to being male, with this result being statistically significant (p = 0.01).
Individuals without epilepsy have approximately four times higher odds of having dental caries compared to those with epilepsy. This outcome is statistically significant (p = 0.02), suggesting that epilepsy might have a protective effect against dental caries or that those with epilepsy might engage in behaviors or receive treatments that lower their caries risk. Similar to the absence of epilepsy, not having Down syndrome is associated with five times higher odds of developing dental caries compared to those with Down syndrome. This result is statistically significant (p = 0.03), indicating that certain characteristics associated with Down syndrome may offer protection against dental caries.
Individuals with partial motor independence have significantly lower odds (about 77% lower) of developing dental caries compared to those with no motor independence. This statistically significant result (p = 0.01) highlights the importance of motor ability in performing oral hygiene tasks effectively.
The absence of toothpaste use is associated with more than nine times higher odds of having dental caries compared to those who use toothpaste. This finding is statistically significant (p = 0.04), underscoring the crucial role of toothpaste, likely due to fluoride, in preventing dental caries. (Table 6)
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Table 6. Adjusted Odds Ratios of Dental Caries Risk in People with Intellectual Disabilities.
4. Discussion
Subjects with intellectual disabilities are more likely to develop dental caries than peers without intellectual disabilities [2] . Our study allowed us to identify associated factors of dental caries among people with intellectual disabilities in the specialized centers of Ouagadougou. Dental caries was significantly associated with Female gender (OR = 4.16; 95% CI = 1.39 - 12.5, p = 0.01), absence of epilepsy (OR = 3.83; 95% CI = 1.16 - 12.62, p = 0.02), absence of Down syndrome (OR = 5.01; 95% CI = 1.09 - 22.91, p = 0.03), partial motor independence (OR = 0.23; 95% CI = 0.07 - 0.71, p = 0.01), not using toothpaste (OR = 9.33; 95% CI = 1.05 - 82.72, p = 0.04).
Females were at high risk of developing caries in our study. There is evidence indicating that many caries risk factors provide a gender bias, placing women at a higher caries risk. Generally, dental caries disproportionally affects the poor and racial or ethnic minorities worldwide, with women suffering more from the disease [9] . Liu and al have shown that caries rates are higher in women than in men [3] . Anusha and al also noted in their study that mean DMFT was low among males when compared to females [10] . Indeed, risk factors for caries in women include different salivary composition and flow, hormonal fluctuations, dietary habits, genetic variations, and particular social roles within their families [11] .
Subjects with epilepsy were less likely to develop caries. It should be noted that the authors do not agree on this subject. So, if for Anjomshoaa and al. [12] , there is a strong association between dental caries and epilepsy, this is not the case for Johnston and al. [13] who showed the opposite. According to Tiwari and al, the observed higher mean values for caries indices are in all likelihood, the result of a conjunction of factors such as poor socioeconomic status of epileptic children, lower frequency of dental clinic visits, regular long-term treatment with sugar-containing medicines, the tendency of parents to avoid dental treatment due to inadequate knowledge about epilepsy, and fear that dentist might provoke seizures during treatment [14] . Further investigations are therefore necessary to understand the possible relationship between caries and epilepsy.
Down syndrome was a protective factor for caries in this study. Indeed, some characteristics found in patients with Down syndrome seem to protect them from the risk of caries. Delayed eruption, reduced exposure time to a cariogenic environment, missing teeth due to agenesis or periodontitis, higher salivary pH and bicarbonate levels (providing a better buffering action), microdontia, the presence of large diastemas and shallow tooth grooves all contribute to this lower risk of dental caries [15] [16] . Silva and al. also reported in a meta-analysis that trisomy was a protective factor against caries [17] . Jesse and al noted characteristics (a low pH and alpha diversity) on the overall composition of the oral microbiome in Down syndrome that present a potentially cariogenic environment. However, the low incidence of caries seen in the literature may maybe because the unique dentition typically seen in Down syndrome impedes the early colonizers of dental plaques [18] .
Subjects with partial independence had a lower risk of developing dental caries compared to those with no independence. Indeed, the degree of motor impairment is directly proportional to the likelihood of developing dental caries [19] . Low physical abilities or decreased manual dexterity among this group could cause difficulty in performing appropriate oral hygiene practices [20] . In many cases, caregivers need to actively assist with daily oral hygiene procedures and sometimes even need to perform this task for people with intellectual disability. It is important to stress that both individuals with intellectual disability, in all age groups, and their caregivers ought to be professionally instructed in proper tooth brushing techniques by dental practitioners within the scope of supportive oral hygiene interventions [21] .
Individuals without toothpaste have a high risk of developing caries. Toothpaste helps to remove plaque and food debris, thus contributing to the reduction of the risk of developing caries [22] . Also, using fluoridated toothpaste is consistently found to reduce dental caries. Use of topical fluoride exposure, such as fluoride mouth rinse, fluoride gels and fluoride varnishes is also recommended as their benefits for oral health are well established throughout the literature [23] .
Individuals who cleaned their teeth less than once a day or never, exhibited an increased odds ratio (OR) of 1.68 ([0.36 - 7.78], p = 0.50) and 2.62 ([0.19 - 36.94], p = 0.47), respectively, compared to those who cleaned their teeth one or more times per day. This result highlights a trend where less frequent teeth cleaning is associated with a higher risk of dental caries among people with ID. However, our findings, while pointing towards the importance of regular toothbrushing, did not show a statistically significant association between the frequency of toothbrushing and the incidence of dental caries, contrasting with Liu et al.’s study [3] , which underscored the positive impact of regular oral hygiene practices on reducing the prevalence of dental caries among children with intellectual disabilities. Our result could be due to a small sample size.
The significant association between dental caries and factors such as gender, specific clinical forms of intellectual disability, motor autonomy, and oral hygiene practices, as identified in our study, underscores the complex interplay of biological, behavioral, and care-related factors in dental health among individuals with intellectual disabilities. Our findings contribute to a nuanced understanding of dental caries’ etiology in this population, highlighting specific risk factors that may guide targeted preventive strategies.
Our study emphasizes the need for a multifaceted approach to dental care in individuals with intellectual disabilities, integrating gender-sensitive, condition-specific, and autonomy-enhancing strategies. As we advance our understanding of dental caries’ associated factors in this population, it is imperative to translate these insights into practice, ensuring that dental health interventions are inclusive, evidence-based, and tailored to meet the unique needs of individuals with intellectual disabilities.
5. Limitations
This was a descriptive and analytical cross-sectional study conducted in Ouagadougou in specialized centers for intellectually disabled persons receiving government funding. To ensure the reliability of the data, the clinical examination was performed by two well-trained and calibrated dentists. Although the measure used to quantify the presence of dental caries (DMF index) underestimates the occurrence of caries lesions according to several authors, it remains the quickest method to apply and is recommended by WHO for this type of survey [22] . In addition, the interviews were conducted in collaboration with the parents and at least one of the subject’s supervisors (psychologist, monitor) using a recommended standardized questionnaire.
However, potential information bias such as underestimation or overestimation of unhealthy and healthy habits may influence the results to some extent. In addition, recall bias, particularly with respect to dietary and dental experience, must also be considered.
6. Conclusion
This study provided information on the prevalence of dental caries among people with Intellectual Disability in Burkina Faso and identified associated factors. Intellectually disabled persons constitute a vulnerable population group that often does not have access to oral health care. There is a great need for targeted education and training for these individuals and for all those who accompany them in specialized facilities. The data collected could allow the managers of centers for people with intellectual disabilities to advocate with their partners for the improvement of the oral health of people with intellectual disabilities.
Abbreviations
DMF: number of Decayed, Missing due to caries, and Filled Teeth index.