Factors associated with dental cavity in children aged six to 36 months old, in Salvador-BA

Abstract Objectives: to analyze the factors associatedwith dental cavity in early childhood. Methods: this is a cross-sectional study on oral health condition of 535 children aged between six and 36 months old, at Family Health Units, in Salvador-BA. Information was collected on socioeconomic conditions, mother and child’s health, eating and oral hygiene habits, and oral examination. Results: the prevalence of dental cavity was 13.64% (CI95%=11.44 -15.84) and the factors associated were: child’s age, number of rooms in the house, “Bolsa Família” (Family Welfare) benefit, prenatal consultations, birth weight and exclusive breastfeeding. Conclusions: socioeconomic conditions strongly influenced oral health, as well as prenatal care and breastfeeding. To prevent childhood cavities, it is pertinent to invest in intersectoral actions and systematized programs, including the medical and nursing staff, as these actions are essential for integral care for the child’s health and quality of life


Introduction
Dental cavity is a worldwide disease and its prevalence and severity are considered high in the age group up to 36 months old and have several factors associated, according to Majorana et al. 1 study.The prevalence of dental cavity for the age group 18 to 36 months old in Brazil, from the index of decayed, missing, and filled teeth (dmf-t) was almost 27% of the examined children, according to the epidemiological study, SB Brasil (Saúde Bucal Brasil) (Oral Health Brazil) in 2003. 2 In the last epidemiological survey, in 2010, at the age of five years old a Brazilian child has, on average, 2.43 teeth with cavity, with a predominance of the decayed component, which is responsible for more than 80% of the index. 3n 2019, results by Chen et al., 4 cavity in five-year-old children was found to be unevenly distributed, however, it is decreasing over time and its factors associated include behaviors related to oral hygiene practice, sugar consumption, parents' knowledge in oral health, and sociodemographic conditions.Dental cavity in this age group can significantly affect the child's quality of life, and oral health education shows potential in prevention. 5abral's 6 study on 640 children aged up to 36 months old showed a high incidence of cavity (22.6%), observing a polarization of the disease, in other words, children with very poor oral health conditions and children with good oral health conditions.
8][9] Health promotion and disease prevention are inserted in the Brazilian health context through the principles and guidelines that govern the Sistema Único de Saúde (SUS) (Brazilian Public Health System), acting in the field of the Estratégia de Saúde da Família (ESF) (Family Health Strategy), through the Política Nacional da Atenção Básica(National Primary Health Care Policy). 3onsidering that cavity is the most prevalent oral disease in Brazil and that it can be prevented effectively with low costs, it is essentialto expand and systematize preventive dental care for children.It is noteworthy that the link between the professional and the family, educational activities, longitudinal monitoring of oral health and treatment will contribute to the development of a cavity-free generation.
Therefore, the aim of this study was to analyze the factors associated with dental cavity in children aged six to 36 months old, in the Estratégia de Saúde da Família (ESF) (Family Health Strategy), in Salvador-BA.

Methods
This is a cross-sectional study involving children aged between six and 36 months old, with a quantitative approach, developed in 2019 in the city of Salvador-BA, which has 2,900,319 inhabitants and is located in the Northeast region according to Instituto Brasileiro de Geografia e Estatistica (IBGE)(Brazilian Institute of Geography and Statistics) in 2021.The city of Salvador has 12 Sanitary Districts (DS), the study was conducted in 11 Unidades de Saúde da Família (USF) (Family Health Units) one per DS, according to the availability and interest of the dental surgeon in participating in this research.
The study sample was established by convenience, through sample calculation made according to the E-sus, a health information system data, used by the city, considering the total population, 15% of prevalence of dental cavity, 80% of power, 5% of significance level and an OR=1.5 for the main association.A design error of 1.5 was added because it is considered as a cluster sample.634 children was the number obtained.The inclusion criteria adopted were children aged six months to 36 months old, residents of covered areas selected by Unidades de Saúde da Família (USF) (Family Health Units) in the city of Salvador-BA, whose parents agreed to participate in the research.
The data collection instrument was a validated questionnaire by Cabral, 6 which contains epidemiological indicators for monitoring the children'sgeneral health conditions, their living and eating habits, and their oral health condition.To start the data collection, the team of examiners was duly selected and calibrated, measuring the Kappa index, to identify the intra and inter-examiner agreement.This calibration was performed by the consensus, from two workshops, including the discussion of the entire research methodology, the examination criteria, the data collection instrument, its indicators, and a moment to discuss in the field about three to four cases, to achieve the consensus and standardization in oral examinations.
The application of the questionnaire was carried out through an interview in a reserved place, which it could be at home or at the Estratégia de Saúde da Família (ESF) (Family Health Strategy) office, respecting the privacy of the participantsin this study.A pilot study was carried out with ten children, being possible to identify flaws and make the necessary adjustments as to the clarity of the questions in the form and adapt it to the reality of the location.
The oral exam was performed using natural light or flashlight, wooden spatula, gauze, gloves, cap, mask, apron, and goggles, following the biosafety rules.The oral exam considered the number of decayed surfaces, white stain, filled teeth, teeth indicaed for extraction, missing teeth, and excluded teeth, represented in an odontogram.
The International Caries Detection and Assessment System (ICDAS) was used, which is intended for the use in epidemiological research and to detect cavitated and non-cavitated stage lesions with acceptable reliability.A code was used for each tooth and then the dmf-t and dmf-s index of the children examined in the study were calculated.Soft tissue, hard tissue, eruption disorders, developmental changes, anomalies and trauma were also evaluated.Upon identifying oral change in the children, the professionals arranged for care at their own health care facility.
All data were entered into a database in the Minitab program and the descriptive analysis of the variables of interest was performed, observing the absolute and relative frequencies and measures of central tendency and dispersion.Next, stratified analysis was performed for an assessment of potential associations.Effect prevalences were observed according to co-variates, and differences between categories were analyzed using Pearson's chi-square test.In conjunction with elements from the theoretical model and literature, this statistical procedure contributed to the selection of the co-variates used in the modeling (p<0.20).
In the multivariate analysis, the method used was unconditional regression.For statistical inference, the 95% Confidence Interval was used.The modeling procedures allowed the construction of the final model to estimate the association of measurement.Poisson Regression was used as an analytical strategy to obtain the Prevalence Ratios.The adjustmentof goodness of the model was verified using Hosmer and Lemeshow's chi-square test.
The research project was submitted and approved by the Research Ethics Committee of at the Universidade Federal da Bahia (UFBA), under the number 2.857.836.

Results
The study population was consisted of 535 children out of a total of 634, since 99 were still starting the eruptive process.Of the total number of children (n=535), 50.28% were female, and as for ethnicity, there was a predominance of black and mixed colored skin (83.93%) (Table 1).
Most of the sample was children living in the covered area by the Unidades de Saúde da Família (USF) (Family Health Units).The descriptive analysis in relation to the socioeconomic profile showed that the mother's schooling up to elementary level was 44.92% and, of the interviewed guardians, 75.88% were married, in a stable union or living together.As for housing, 42.05% live in a home up to 4 rooms, and 27.1% live with more than 5 people in a home.
The mother's health and the child'sgeneral health showed that most mothers had more than 8 prenatal consultations (59.06%), most children were of a normal childbirth (56.26%), at adequate weight (>2500g) at birth (90.46%), and exclusive breastfeeding (82.80%).As for the children'seating habits in the research, 91.08% had already access to sugar, 93.19% were fed at night, 73.08% slept in a shared bed, 55.51% performed oral cavity cleaning, and 84.33% did not share toothbrushes (Table 1).
In the descriptive analysis of the children's oral health regarding mucosal alteration, 95.9% did not present it, 39.12% presented candidiasis, 31.06%presented fraenum of the lip altered, only 4.83%, presented short lingual frenulum and 24.34% presented clean malocclusion (Figure 1).
As for the prevalence of dental cavity was found 13.64% and the dmf-t index=0.21(SD=1.25),minimum value=0 and maximum value-16, with a predominance of the decayed component (100%) (data not listed).
In the bivariate analysis between dental cavity occurrence (ICDAS) were found as statistically significant associated variables, exclusive breastfeeding (six months) (p=0.042) and "Bolsa Família" (Family Welfare) benefit (p=0.047),protective factors for cavity prevention.
Considering the bivariate association between dental caries occurrence (ICDAS) and associated variables, the following were selected for the multivariate model: child's age, number of rooms at home, "Bolsa Família" (Family Welfare) benefit, number of prenatal consultations, birth weight, and exclusive breastfeeding (Table 1).

Discussion
Of the 535 children in this study, there was a slight predominance of females, predominantly black and mixed colored skin, with the majority of the sample consisting of children living in the covered area by the Unidades de Saúde da Família (USF) (Family Health Units).As for the socioeconomic profile, more than half of the mothers had completed elementary school level, and most of them were married, in a stable union or living together.As for housing, almost half of the children live in homes with up Bivariate association between dental cavity occurrence (ICDAS) and associated variables in pre-schoolers, Salvador-BA, 2019 (N=535).The prevalence of cavity in early childhood children has been studied in many countries, with diverse epidemiological, cultural, and socioeconomic situations, and verifying a wide variation. 5,10In this study, the prevalence was 13.64%, and there is a statistically significant association of increasing prevalence ofcavity with the child's age, given the cumulative nature of the disease, in agreement with the results of similar studies. 5,9,111][12][13] Given the variations in prevalence of cavity in several countries, as well as in several Brazilian States, it becomes pertinent to prioritize strategies for prevention and promote oral health in early childhood in the Primary Care, through the Estratégia de Saúde da Família (ESF) (Family Health Strategy).

Variables
Dentistry in early childhood has been producing potentialities in oral health prevention and promoting actions.][16] Most studies show that early childhood cavity is also strongly associated with social factors, such as family income, schooling, number of children, and even the mother's need for dental treatment, confirming the findings of this study, which identified social factors

Figure 1
Oral health conditions in the 6 to 36 months old age group in Salvador, BA, in 2019.
associated with early cavityries. 12,17Alkhtib et al. 18 completment that the low socioeconomic level produces a lack of awareness in families regarding prevention and treatment of oral diseases in early childhood, with a generalized negligence.Baggio et al. 19 identified early childhood cavity as a marker of social inequalities, stating that socioeconomic level is associated with increased prevalence ofcavity.According to Stephen et al., 9 the parents' schooling is also related to early childhood cavity, according to Chaffee et al. 20 studies, the mothers' precarious socioeconomic conditions are reflected in the access to information; the lower the mothers' schooling, the greater the chances of cavity, since these mothers do not receive sufficient guidance on oral hygiene and nutrition for the child's oral health care.In this study, 89.01% of the children whose mothers had schooling higher than high school were cavity-free, but it was not statistically significant, agreeing with Fan et al., 21 study who also found no association between parents' schooling level with the increased cavity in children in early childhood.
In this study, a statistically significant association was found with cavity, the few number of rooms at home where the child lives, and as a protective factor, receiving the Bolsa Família (Family Welfare) benefit.Stephen et al. 9 and Moimaz et al. 17 reinforce this finding by stating that social assistance improves the economic conditions of the family, influencing better oral health care.In contrast, Lee et al. 22 study did not find similar results.
Children'soral health conditions in early childhood are related to eating habits, especially the intake of sucrose, which increases the likelihood of cavity in socially vulnerable children. 23It was identified in this study that 91.08% had already access to sugar, but no statistically significant association was found, disagreeing with the results of several studies, 8,20,24,25 perhaps because of the children'sage.Ghazal et al. 10 state that the consumption of sugary food more than once a day increases 9.2% of chances of a child to have cavity; Chaffee et al. 20 also found relevant data, in which 95% of the children who have a cariogenic diet have cavity.
In this study, breastfeeding had a statistically significant association as a protective factor against cavity, confirming the findings of Majorana et al. 1 and Cidro et al. 26 who identified the association of breastfeeding with the reduction of early cavity in this age group, and that pregnant women and mothers' need to be oriented to maintain breastfeeding and promote the child'shealth.However, some studies have identified the opposite, such as that of Kato et al. 27 in a population-based study with more than 43,000 six-months-old children, observed that exclusive and mixed breastfeeding at this age group contribute to increased prevalence of cavity.
Nakayama and Mori 25 showed that there is evidence of an association between nighttime breastfeeding and early prevalence of cavity.In this study, 93.19% of children had nighttime feeding, but there was no statistically significant association.These contradictions are important to analyze that cavity problem is complex and involves socioeconomic and cultural context in which the child is inserted.
As for oral hygiene habits, the results of this study showed that 44.48% of the children in the study did not clean their oral cavity, and this indicator did not show a statistically significant association with the increase of cavity.Gomes et al. 28 in a study with 165 children also found no significant association between cavity and hygiene habits, confirming the findings of this study, but contradicting the results of another study. 24This reality found in this study may be related to the use of fluoridated toothpastes, as well as genetic factors, among others, since this is a multifactorial disease.It is important to include oral hygiene issues in health promotion and disease prevention, themesrelated to oral hygiene as educational activities, and preventive programs are essential for the inclusion of oral hygiene habits in early childhood. 13,18,19,21uriakose et al. 13 showed that 76.1% of the children with brushing habits astwice daily,were free of cavity, and that these habits are modeled in the family environment.Nunes et al. 23 identified tooth brushing as a protective factor in a group of low cavity risk, while in this study no statistically significant association was found.Aljarallah et al. 8 and Gopal et al. 12 added the importance of fluoride use in toothpastes as a protective factor.
Many studies state that the improvement of oral hygiene habits as well as the decrease in the prevalence of cavity in this age group are enhanced by access to a dentist, and the greater the follow-up of the child's oral health with a dentist, the lower the possibility of having cavity. 12,13,18,21,23onsidering that cavity is a multifactorial chronic disease, some limitations and challenges were identified in this study, such as the type of a cross-sectional study, which only observes the population at a given time, the information about the child's oral health and pregnancy based on family members' memory.The sample size was smaller than previously calculated, limited to locations according to the Unidades de Saúde da Família (USF) (Family Health Units), which may have restricted the results of the analyses.We suggest a longitudinal study to further investigate the factors associated with cavity, as well as intervention studies at the local level.Studies with qualitative analyses and with larger samples would also complement the results of this study.
In agreement with the results of this study, Abanto et al. 16 state that the first thousand days of a child are like a "window of opportunity," a special time for the adoption of habits and lifestyle choices that will influence oral health in early childhood.The earlier a child starts oral health care, the better their health indicators will be.Moimaz et al. 29 state that maternal and child health actions need to be equally monitored, ensuring access to prenatal and childcare services, as well as dental prenatal care.The Estratégia de Saúde da Família (ESF) (Family Health Strategy) teams have the responsibility to develop educational actions focused on raising the families' awareness about prevention of the diseases and health promotion.
The reality of the children'soral health in early childhood is worrisome, because there is a polarization of the disease, so children in situation of social vulnerability are the most affected and, when this happens, it is in the most severe form of the disease.In the context of Primary Care through the Estratégia de Saúde da Família (ESF) (Family Health Strategy), it is possible to advance with the implementation of early oral health care programs, beginning in the prenatal period, in order to provide as much guidance and clarification as possible regarding oral health care in early childhood.
The results of this study showed factors associated such as the child's age, the number of rooms in the homes, families receiving the Bolsa Família (Family Welfare) benefit, the number of prenatal consultations, and exclusive breastfeeding.These findings reinforce the need for greater investment in intersectoral educational actions in the public health field, with the involvement of the entire family health team, collaborating with the improvement of oral health conditions in early childhood.

Final
model of the exploratory Poisson regression analysis of variables associated with the presence of dental cavity (ICDAS) in pre-schoolers, Salvador-BA, 2019 (N=535