Dental Caries in Childhood after COVID-19 Pandemic in Salvador-BA, Brazil

Introduction

Early Childhood Caries (ECC) remains a significant public health issue, with profound effects on child development. This condition is defined by the International Association of Paediatric Dentistry as the presence of one or more decayed (cavitated or non-cavitated), missing, or filled tooth surfaces (due to caries) in any primary tooth of a child under six years of age, determined by biological, behavioral, and psychosocial factors related to the individual's environment [1]. The family context, including all aspects of their lifestyle (socioeconomic factors and lifestyle choices), can influence children's oral health, including the onset of caries. Thus, parental behaviors and knowledge regarding oral health directly impact their children's oral health, in addition to cultural factors and the parents' socioeconomic and educational levels [2].

According to the World Health Organization, untreated caries in primary teeth affects 510 million children worldwide, a significant figure that places caries at the top of the most prevalent diseases and, therefore, a major public health issue. In developed countries, the prevalence of caries has shown a downward trend in recent years, and the same has been observed in Brazil. However, there is a polarization in its occurrence due to socioeconomic differences. For example, in Brazil, 60% of the caries burden is concentrated in the North and Northeast regions [3].

The COVID-19 pandemic exacerbated the global situation from a social, political, and economic perspective, directly impacting child development. During the pandemic climax, family dynamics shifted with the suspension of non-essential activities, work moved to a remote format, and schools transitioned to online (or non-existent) education. This led to unhealthy behaviors, confinement, reduced leisure time and outdoor physical activities, income reduction, and family illness and death. This entire scenario brought various insecurities for families, with parents experiencing peaks of stress, resulting in physical and mental health problems that also affected children's health [4].

Additionally, healthcare services were reduced, and dental professionals had their activities suspended, with a slow recovery in 2021. The consumption of ultra-processed and sugary foods increased as a form of comfort. Children with sleep disturbances increased nighttime bottle use. These dietary changes may have contributed to the rise in obesity, diabetes, cardiovascular diseases, and dental caries [3]. In this context, this study aims to analyze the prevalence of dental caries in preschool-aged children attending public daycare centers in Salvador, Bahia, in the years 2022 and 2023, as well as to identify the associated factors.

Methodology

This is a cross-sectional epidemiological study. Data collection took place in Salvador, Bahia, in 2022 (August to November) and 2023 (March and April). The study was approved by the Research Ethics Committee of the School of Dentistry at UFBA – CAAE: 60817222.6.0000.5024. Furthermore, oral examinations were only conducted after the parents or guardians signed the Informed Consent Form (ICF) and with the child's assent. A convenience sample of children aged 2 to 5 years, attending municipal public daycare centers, was selected based on the authorization of the Municipal Education Department of Salvador-BA. The choice of daycare centers was made by the department’s recommendation and because these centers represent the largest social space for children in half of the city’s health districts. Data collection occurred within the school environment during the academic year and was conducted by trained and calibrated dental professionals and dental students from the School of Dentistry at the Federal University of Bahia (UFBA). In addition to oral exams, a self-administered structured questionnaire was given to the children's guardians to investigate family environment aspects, including socioeconomic, behavioral, and psychosocial factors in the context of the COVID-19 pandemic.

Dental caries were evaluated according to the criteria proposed by the Deft index (Decayed, Missing, and Filled Teeth), the same index used in the most recent national epidemiological surveys (Brazil, 2004 and Brazil, 2012). ECC was defined as the presence of caries in all examined children with a dmft score greater than zero. The collected information was entered into an Excel database, and statistical analysis was performed using STATA 14. Data were analyzed descriptively and exploratorily to identify potential associations. The Chi-square test was used with a significance level of 5% to identify variables associated with dental caries. Robust Poisson regression was used to estimate prevalence ratios and their respective 95% Confidence Intervals, considering caries as the dependent variable. In the multivariate analysis, the stepwise forward method was adopted to include the final adjusted models. Independent variables with a p-value <0.20 for each outcome in the univariate analysis were incorporated, and those with a p-value <0.05 were retained in the final models.

Results

A total of 440 preschool children aged 2 to 5 years, attending municipal public daycare centers in Salvador, Bahia, participated in this study during the years 2022-2023. The average age of the study population was 55 months, and the majority were Black or mixed race (88.86%). Female children were more prevalent (52.73%). Most families reported a household income of up to one minimum wage (73.64%), and most of mothers interviewed had completed high school or higher education (58.64%). Most families received financial aid during the pandemic (66.14%), and 72.95% reported that there was no impact on their household income during this period. Additionally, 5% of the children experienced violence during the pandemic (Table 1).

Table 1: Absolute and Percentage Distribution of Preschoolers According to Socioeconomic Aspects. Salvador-BA, 2022-2023 (n=440)

Regarding behavioral aspects and oral health conditions, most children ate daily at the daycare (80.91%), 75% experienced no changes in their diet during the pandemic, 73.41% never had supervised brushing, and nearly 14% did not have dental biofilm. The children spent more time watching television (58.64%), did not play outdoors during the pandemic (65.45%), and did not attend remote classes (63.18%) (Table 2). Caries were present in 30.91% of the sample at the time of the examination. The Dmft Index was 1.1, and the average number of decayed primary teeth was 0.98.

Table 2: Absolute and Percentage Distribution of Preschoolers According To Behavioral Aspects and Oral Health Problems. Salvador-BA, 2022-2023 (n=440)

Table 3 presents the bivariate analysis regarding the occurrence of ECC (in Primary Dentition) and its relationship with the investigated covariates. Several factors were associated with this oral health issue:

• Older Age (55 months or more)

• Lower Household Income

• Receiving Pandemic-Related Financial Aid

• Lower Maternal Education

• The Child Experiencing Violence during the Pandemic

• Not Playing Outdoors.

       *Salário mínimo em 2022: R$1.212,00

Table 3: Bivariate Analysis of the Absolute and Percentage Distribution of Preschoolers according to Socioeconomic Aspects. Salvador-BA, 2022 (n=440)

Table 4: Bivariate Analysis of the Absolute and Percentage Distribution of Preschoolers according to Behavioral Aspects and Oral Health Problems. Salvador-BA, 2022 (n=440)

In the multivariate analysis, lower household income (up to one minimum wage) (adjusted PR = 1.57; 1.04-2.38, 95% CI) and the fact that the child did not play outdoors during the pandemic (adjusted PR = 1.32; 1.01-1.74, 95% CI) were associated with ECC (Table 5).

Table 5: Adjusted Prevalence Ratios, Respective 95% Confidence Intervals, and p-values, for the Association between Socioeconomic and Behavioral Factors and Early Childhood Caries in Preschoolers, Obtained by Robust Poisson Regression, Salvador-BA, 2022. (n=440)

Discussion

This study involved 440 preschool children, and the prevalence of caries was 30.91%. The average age of the study population was 55 months, predominantly composed of Black and mixed-race individuals. In the multivariate analysis, lower income and the child not playing outdoors during the pandemic were associated with a higher occurrence of caries, a possible proxy variable for poorer nutrition, parental overload, and/or a stressful family environment. Caries is the most prevalent disease in the world, and although there is a global trend toward a decrease, according to WHO data, its distribution is unequal, leading to a polarization among the most vulnerable populations, thereby presenting a public health challenge, as it is a disease linked to biological, behavioral, and socioeconomic determinants. Investigations worldwide report that caries leads to various problems in early childhood, including difficulties in socialization, smiling, frequent pain, nutritional impact, school absenteeism, and sleep disturbances. These issues negatively affect the child's quality of life and are psychosocial burdens that require early diagnosis and treatment for caries, as well as subsequent hygiene and nutrition education.

Global literature has revealed an extremely important issue: the polarization of caries among the most vulnerable populations. During the COVID-19 pandemic and post-pandemic period, which exacerbated socioeconomic inequalities, changes in lifestyle and unhealthy eating habits led to increased investigations into the impact of these factors on the occurrence of caries. In the study by Uribe et al., the prevalence of caries in primary teeth worldwide varies from 30% (Africa) to 82% (Oceania) among continents, with China showing a prevalence of 89% and Singapore 16% [5]. This indicates significant discrepancies within nearby territories. Graesser et al. highlighted a prevalence of caries of 56.6% in Australia, and in that same study, children from unfavorable socioeconomic backgrounds, such as those with health cards, non-English origins, and indigenous backgrounds, showed higher levels of the disease.

In this study, family income and low maternal education were associated with childhood caries in the bivariate analysis (p<0.05); in the multivariate analysis, family income was one of the factors that remained related to this condition (RP=1.57; 1.04-2.38 95% CI). In the European study by Foxman et al., it was observed that lower family income and maternal education (up to high school or less) increased the risk of childhood caries by at least two times [6]. The investigation by Garcia-Pérez et al., conducted with rural children in Mexico, showed that populations with high marginalization indices are more susceptible to caries [7]. Another study conducted in Montevideo, Uruguay, found a higher prevalence of caries among preschoolers in low socioeconomic status populations (74.90%), and for mothers with low education levels, the prevalence of children with caries was 77.90%, which showed statistical significance (p-value <0.01).

Exclusive breastfeeding and adequate family income are protective factors associated with the occurrence of caries. In the survey by Santos et al., conducted with 535 children aged 6 to 36 months in Salvador-BA, in areas covered by Family Health Units, the prevalence of dental caries was 13.64%, where older children's age was also associated with caries, similar to this study, resulting from the cumulative nature of the disease; however, breastfeeding was not investigated in this study [8]. Almeida et al., when evaluating the oral conditions of 2,788 children attending municipal public preschools and Family Health Units, aged 36 to 60 months in Salvador-BA, observed a prevalence of caries of 38.38% and a dmft index of 1.53 [9]. These findings were higher than those observed in this study (prevalence of caries of 30.91% and dmft index of 1.1). In the SB Brazil 2010 survey, the dmft values in the Salvador region were 1.70, in the Northeast state 2.89, ranking third among states with the highest indices, behind the North and Midwest, and the index for Brazil was 2.43.

Tso et al. analyzed the impact of COVID-19 on the mental health of children with Special Educational Needs (SEN) in Hong Kong and the risk of abuse [10]. The authors observed that rates of physical aggression significantly increased during the pandemic: 23.5% of children experienced at least one episode of severe aggression, 1.9% suffered very severe physical aggression, and 80.5% were victims of psychological aggression, demonstrating that the interruption of rehabilitation, medical care, and classes had detrimental effects on the mental health of children and their caregivers/parents. In this investigation, caries was associated with the fact that the child suffered aggression during the pandemic (p=0.047).

Increased parental stress during the pandemic also led to worse stress levels in children, necessitating self-regulation of their energies. Various behavioral changes influenced overall health care for children and also oral health, triggering an increase in the prevalence of caries during this period. In the present study, not going outside to play was associated with caries (adjusted RP=1.32; 1.01-1.74 95% CI).

In the study by Buechel et al., conducted in the context of the COVID-19 pandemic with German families of children aged 0-3 years, it was found that 37.7% experienced parental stress, 18.5% had symptoms of depression, and 30.1% anxiety, where infants and children also showed mental health problems correlating moderately with parental stress. Research conducted in India by Sama et al. revealed that 73.15% of children exhibited signs of increased irritability and 51.25% an increase in anger during the pandemic [ 11]. All these findings are highly relevant for developing preventive measures and interventions regarding mental health. This investigation revealed the oral health situation, especially regarding caries, in preschool children (2 to 5 years old) during the COVID-19 pandemic in Salvador-BA. The analysis of its findings must be conducted with caution, as it is not guaranteed that the exposure to the evaluated factors preceded the occurrence of caries; additionally, the interviews conducted with the caregivers were self-administered, which may have contributed to issues in recording information, leading to limitations in classifying the covariates present in the questionnaire.

Conclusion

The COVID-19 pandemic brought various impacts on society, among which significant changes in the material and psychosocial conditions of families stand out. These conditions are fundamental for child development and are directly related to oral health issues. Dental caries remains a public health problem to be addressed in Salvador-BA, considering the high prevalence found (30.91%). Moreover, its occurrence was associated with sociodemographic and psychosocial aspects strongly influenced by the pandemic, such as the child's older age (55 months or older), reduced family income, and the child playing outdoors during the pandemic. Public policies that combat social inequalities in our country, as well as programs specifically aimed at children's oral health, are necessary for changes in the epidemiological profile of oral diseases among children [12-15].

References