Socio-behavioral factors influence prevalence and severity of dental caries in children with primary dentition

The aim of this study was to analyze the influence of sociobehavioral variables on the prevalence and severity of dental caries in 4to 6-year-old children. A cross-sectional study was performed on a sample of 1993 children enrolled in 58 public preschools from Araçatuba City, São Paulo State, Brazil, during 2010. The exams were made using the decayed, missing, and filled teeth index (World Health Organization methodology) and detection criteria for non-cavitated lesions. A tested, self-administered questionnaire was sent to parents to obtain information about their socio-behavioral characteristics. Standardization was performed to verify concordance among examiners (kappa = 0.84). The prevalence of cavitated caries lesions was 41.2% (821), and the prevalence of both, cavitated and non-cavitated caries lesions, was 43.9% (875). The means ± standard deviations of the decayed, missing, and filled teeth index for children aged 4, 5, and 6 years were 1.18 ± 2.45, 1.65 ± 2.67, and 1.73 ± 2.77, respectively. Caries were significantly more prevalent in children from families with low incomes and low educational levels. The presence of dental caries was associated with access to dental services (p < 0.05). The associations between both, cavitated and non-cavitated dental caries lesions, and the frequency of oral hygiene were statistically significant. The prevalence of dental caries in preschoolers was strongly associated with factors related to the children’s parents. Therefore, information about parents’ socio-economic status, behaviors, and attitudes in relation to oral health should be considered when planning prevention and educational programs for the oral health of preschool children. Descriptors: Dental Caries; Child, Preschool; Epidemiology. Introduction In recent decades, there have been considerable improvements in the oral health of preschoolers in many developed countries.1 However, dental caries still affect a considerable proportion of children. Recent studies have shown that dental caries have decreased in Latin America and the Caribbean.2 In Brazil, there was a 17% decrease in dental caries from 2003 to 2010, and the decayed, missing, and filled teeth index (dmft index) for 5-year-old children decreased from 2.80 to 2.30.3 Concomitantly with caries decreasing, there was a growing polarization in its distribution.4 In some areas, the dmft index increased and was concentrated in small parts of the population. The strong polarization in Declaration of Interests: The authors certify that they have no commercial or associative interest that represents a conflict of interest in connection with the manuscript. Submitted: Apr 18, 2012 Accepted for publication: Aug 28, 2012 Last revision: Sep 10, 2012 Borges HC, Garbín CAS, Saliba O, Saliba NA, Moimaz SAS 565 Braz Oral Res., (São Paulo) 2012 Nov-Dec;26(6):564-70 disease distribution, even among young children, indicates that a considerable proportion of this group does not receive benefits from traditional prevention programs.5 Caries experience in primary dentition is considered the strongest predictor of caries in permanent dentition.6 Therefore, mapping patterns of oral health in young children and studying the risk factors for caries and their distribution are essential for the new panorama of dental caries, allowing to understand the caries behavior and the best ways to control and prevent it. The number of children with caries located in the enamel alone, without cavitation, has been increasing and has been noted not only by general dentists, but also by epidemiologists and health service planners.7,8 The inclusion of both types of caries lesions (cavitated and non-cavitated) in epidemiological research can improve study sensibility, mainly in populations with a low prevalence of caries. In these populations, non-cavitated caries lesions show a slow progression pattern and are observed principally in early stages.9,10 Caries epidemiology also involves the study of variables that can influence its occurrence and severity, including social, demographic, and behavioral factors, such as ethnicity, family income, parents’ educational level, knowledge and beliefs of them and oral hygiene habits. Cross-sectional studies have shown the complex interaction among these factors and caries in preschoolers.11 However, few studies have considered the inclusion of non-cavitated caries lesions in deciduous teeth. Therefore, the aim of this study was to evaluate the influence of socio-behavioral variables on the prevalence and severity of dental caries in children aged 4 to 6 years old. Methodology Study design A cross-sectional, epidemiological study was performed in 4to 6-year-old male and female children who lived in Araçatuba during 2010. Araçatuba is a city in São Paulo state, Brazil, with 181,618 inhabitants. The income per capita is approximately US$7,355.00/year, the child mortality rate is 10.29/100, and the Human Development Index is 0.848. Since 1972, the city has added 0.6 to 0.8 mg/l fluoride to the public water supply. The sample consisted of children from 4 to 6 years old, who were enrolled in the 58 public preschools in Araçatuba during 2010 (n = 3,697). Exclusion criteria were: • children whose parents did not authorize exams, • children who had authorization but did not cooperate during exam, and • children who were not present on the three dates scheduled for exams. The final sample consisted of 1,993 (53.9%) children. All included children underwent a clinical evaluation, and their parents answered the questionnaire. Questionnaire A tested, semi-structured, self-administered questionnaire and a written consent form were sent to parents/responsible adults. The questionnaire included variables related to the parents’ socio-economic and educational levels, food habits, children’s oral hygiene habits, access to dental services, and reasons for consultation. All questionnaire items were evaluated by a panel of five dentists with research interests and expertise in clinical exams, and a pilot study was performed that confirmed its adequacy. Clinical exams Clinical exams were performed by 5 teams composed of one examiner and one assistant. Diagnostic criteria for dental caries followed the World Health Organization (WHO) recommendation, using a CPI probe (WHO) and a number 5 plane oral mirror under natural light.12 When necessary, before the clinical exam, it was used to gaze at and to clean the tooth surface. The dmft index was calculated, and non-cavitated lesions were registered according to criteria recommended by the Workshop on Diagnosing and Reporting ECC for Research Purposes.13 Rampant caries were recorded when the child had one or more smooth surfaces that were cavitated, missing, or filled in the primary maxillary anterior teeth. Socio-behavioral factors influence prevalence and severity of dental caries in children with primary dentition 566 Braz Oral Res., (São Paulo) 2012 Nov-Dec;26(6):564-70 Rampant caries were also recorded when the dmft index was ≥ 5 for 4-year-old children or when the dmft index was ≥ 6 for 5and 6-year-old children.13 Standardization of diagnosis All examiners were trained prior to the study. The calibration process consisted of a theoretical phase that involved studying indicators and trials, and a practice phase that involved performing exams and discussions using the consensus technique.12 The kappa test for dmft evaluation was applied to verify concordance among inter-examiners, and a mean value of 0.842 was obtained. No calibration was performed for the assessment of noncavited caries lesions, and this is a limitation of this study. As all examiners have clinical experience and were previously trained, concordance among intraexaminers was not assessed. Data analysis Data analysis was performed using BioEstat version 5.3 (Instituto Mamirauá, Manaus, BR)14 and Epi-Info version 3.5.1 (Centers for Disease Control and Prevention, Atlanta, USA)15 software. The dependent variables were presence of dental caries, rampant caries, and dental caries including non-cavitated lesions. The chi-squared test or Fisher’s test at a 5% level of significance was used to verify the association of dependent and independent variables (parents’ education level, monthly family income, access to dental services, and frequency of tooth hygiene). The data were expressed as the mean  ±  standard deviation. A multivariate analysis was performed using logistic regression (STATA software, version 10, StataCorp LP, College Station, USA). The variables that had shown statistical significance were entered into the model, and the results were expressed as an odds ratio (OR) with a 95% confidence interval (CI). Ethical aspects This study was approved by the Ethical Committee on Research with Humans of the Araçatuba Dental School Unesp, process number 1577-2010. Children were examined only when they had a written consent form signed by their parents or responsible adults. Results A total of 1,993 children were examined, of which 984 (49.4%) were boys and 1,009 (50.6%) were girls. A total of 821 (41.2%) children had dental caries, and when non-cavitated lesions were included, the total was 875 (43.9%) children. The mean dmft index was 1.53 ± 2.63. Rampant caries were observed in 16.2% (323) of children. In Table 1, the children were subdivided by age (4, 5, and 6 years) to define the characteristics of each age group. The mean dmft index increased with increasing age. There was a higher prevalence of rampant caries among older children, and a higher prevalence of children free of caries among 4 years 5 years 6 years Total


Introduction
In recent decades, there have been considerable improvements in the oral health of preschoolers in many developed countries. 1However, dental caries still affect a considerable proportion of children.Recent studies have shown that dental caries have decreased in Latin America and the Caribbean. 2In Brazil, there was a 17% decrease in dental caries from 2003 to 2010, and the decayed, missing, and filled teeth index (dmft index) for 5-year-old children decreased from 2.80 to 2.30. 3 Concomitantly with caries decreasing, there was a growing polarization in its distribution. 4In some areas, the dmft index increased and was concentrated in small parts of the population.The strong polarization in Declaration of Interests: The authors certify that they have no commercial or associative interest that represents a conflict of interest in connection with the manuscript.
Braz Oral Res., (São Paulo) 2012 Nov-Dec;26 (6):564-70 disease distribution, even among young children, indicates that a considerable proportion of this group does not receive benefits from traditional prevention programs. 5aries experience in primary dentition is considered the strongest predictor of caries in permanent dentition. 6Therefore, mapping patterns of oral health in young children and studying the risk factors for caries and their distribution are essential for the new panorama of dental caries, allowing to understand the caries behavior and the best ways to control and prevent it.
The number of children with caries located in the enamel alone, without cavitation, has been increasing and has been noted not only by general dentists, but also by epidemiologists and health service planners. 7,8The inclusion of both types of caries lesions (cavitated and non-cavitated) in epidemiological research can improve study sensibility, mainly in populations with a low prevalence of caries.In these populations, non-cavitated caries lesions show a slow progression pattern and are observed principally in early stages. 9,10aries epidemiology also involves the study of variables that can influence its occurrence and severity, including social, demographic, and behavioral factors, such as ethnicity, family income, parents' educational level, knowledge and beliefs of them and oral hygiene habits.Cross-sectional studies have shown the complex interaction among these factors and caries in preschoolers. 11However, few studies have considered the inclusion of non-cavitated caries lesions in deciduous teeth.Therefore, the aim of this study was to evaluate the influence of socio-behavioral variables on the prevalence and severity of dental caries in children aged 4 to 6 years old.

Methodology Study design
A cross-sectional, epidemiological study was performed in 4-to 6-year-old male and female children who lived in Araçatuba during 2010.Araçatuba is a city in São Paulo state, Brazil, with 181,618 inhabitants.The income per capita is approximately US$7,355.00/year, the child mortality rate is 10.29/100, and the Human Development In-dex is 0.848.Since 1972, the city has added 0.6 to 0.8 mg/l fluoride to the public water supply.
The sample consisted of children from 4 to 6 years old, who were enrolled in the 58 public preschools in Araçatuba during 2010 (n = 3,697).Exclusion criteria were: • children whose parents did not authorize exams, • children who had authorization but did not cooperate during exam, and • children who were not present on the three dates scheduled for exams.
The final sample consisted of 1,993 (53.9%) children.All included children underwent a clinical evaluation, and their parents answered the questionnaire.

Questionnaire
A tested, semi-structured, self-administered questionnaire and a written consent form were sent to parents/responsible adults.The questionnaire included variables related to the parents' socio-economic and educational levels, food habits, children's oral hygiene habits, access to dental services, and reasons for consultation.All questionnaire items were evaluated by a panel of five dentists with research interests and expertise in clinical exams, and a pilot study was performed that confirmed its adequacy.

Clinical exams
Clinical exams were performed by 5 teams composed of one examiner and one assistant.Diagnostic criteria for dental caries followed the World Health Organization (WHO) recommendation, using a CPI probe (WHO) and a number 5 plane oral mirror under natural light. 12When necessary, before the clinical exam, it was used to gaze at and to clean the tooth surface.
The dmft index was calculated, and non-cavitated lesions were registered according to criteria recommended by the Workshop on Diagnosing and Reporting ECC for Research Purposes. 13Rampant caries were recorded when the child had one or more smooth surfaces that were cavitated, missing, or filled in the primary maxillary anterior teeth.
Rampant caries were also recorded when the dmft index was ≥ 5 for 4-year-old children or when the dmft index was ≥ 6 for 5-and 6-year-old children. 13

Standardization of diagnosis
All examiners were trained prior to the study.The calibration process consisted of a theoretical phase that involved studying indicators and trials, and a practice phase that involved performing exams and discussions using the consensus technique. 12The kappa test for dmft evaluation was applied to verify concordance among inter-examiners, and a mean value of 0.842 was obtained.No calibration was performed for the assessment of noncavited caries lesions, and this is a limitation of this study.As all examiners have clinical experience and were previously trained, concordance among intraexaminers was not assessed.

Data analysis
Data analysis was performed using BioEstat version 5.3 (Instituto Mamirauá, Manaus, BR) 14 and Epi-Info version 3.5.1 (Centers for Disease Control and Prevention, Atlanta, USA) 15 software.
The dependent variables were presence of dental caries, rampant caries, and dental caries including non-cavitated lesions.The chi-squared test or Fisher's test at a 5% level of significance was used to verify the association of dependent and independent variables (parents' education level, monthly family income, access to dental services, and frequency of tooth hygiene).The data were expressed as the mean ± standard deviation.A multivariate analysis was performed using logistic regression (STATA software, version 10, StataCorp LP, College Station, USA).The variables that had shown statistical significance were entered into the model, and the results were expressed as an odds ratio (OR) with a 95% confidence interval (CI).

Ethical aspects
This study was approved by the Ethical Committee on Research with Humans of the Araçatuba Dental School -Unesp, process number 1577-2010.Children were examined only when they had a written consent form signed by their parents or responsible adults.
In Table 1, the children were subdivided by age (4, 5, and 6 years) to define the characteristics of each age group.The mean dmft index increased with increasing age.There was a higher prevalence of rampant caries among older children, and a higher prevalence of children free of caries among younger children (Table 1).
Table 2 shows the relationships among caries experience and parents' educational level, family income, and behavioral variables.Caries, rampant caries, and caries including non-cavitated lesions were significantly more prevalent in families with a lower educational level and lower monthly income.Caries, rampant caries, and caries including noncavitated lesions were significantly more prevalent in children that had access to dental services than in those without access.Children that practiced dental hygiene two or more times per day had less caries than those who did not practice dental hygiene or practiced once per day.This association was statistically significant only when non-cavitated lesions were included (Table 2).Multivariate analysis confirmed that low educational level, low family income, and access to dental services were independently associated with the presence of caries, ram-pant caries, and caries including non-cavitated lesions.Children who did not practice dental hygiene or who practiced once per day had a tendency to have more caries, when non-cavitated lesions were included (Table 3).Among all affected children, only 2.7% (53) had a dmft index ≥ 10 (Figure 1).The decayed component contributed most to the dmft index value, with percentages of 89%, 82%, and 78% for children aged 4, 5, and 6 years, respectively (Figure 2).

Discussion
This study analyzed the prevalence of dental caries and its relationship with socio-behavioral factors.The analysis also included non-cavitated lesions in the diagnostic criteria, and demonstrated a tendency in the association between hygiene frequency and dental caries.Therefore, children who had their teeth cleaned two or more times per day  had a tendency of lower caries prevalence than those who had their teeth cleaned only once per day or none.In previous studies in some European countries, parental help during tooth brushing and the frequency of oral hygiene were considered the most significant determinants for childhood caries. 16,17owever, no relationship between these variables was noted in an American study. 18he dmft and decayed, missing, and filled surfaces (dmfs) indexes are universally accepted, and allow epidemiological data to be compared from different studies around the world.By including the diagnosis of caries in enamel without cavitation, the new criteria could lead to better preventive dental services.Collecting data on both cavitated and noncavitated lesions would provide additional knowledge about caries progression in deciduous teeth and during early childhood. 13,19omparing the results of this study with those of a previous study performed in the same city in 1998, a decrease in caries prevalence was observed.The mean dmft index values found in the present study for children aged 4, 5, and 6 were 1.18, 1.65, and 1.72, respectively, and were lower than those found in 1998 (1.53, 2.28, and 2.27 for children aged 4, 5, and 6, respectively). 20There was a 13.13% increase in number of caries-free children when our results (55.30%) were compared with the results from 1998 (42.17%). 20ur results showed a similar percentage of caries-free children in comparison to those of previous international studies from the United Kingdom (rate of 60.0%) 21 and Norway (rate of 66.0%). 22Nevertheless, the level of caries-free children did not meet the goal established by the WHO/FDI for 2010 that 90% of children should be free of caries at age 5 and 6 years.It is important to note that studies must be compared with caution because there are variations in the diagnostic criteria and in the selection of indices used to evaluate the disease in this age group.
The results showed that only 2.7% (53) of affected children had a dmft index ≥ 10.Among the 1993 children, 16.2% (323) had rampant caries with high dmft index values.These children represent a significant group that requires dental treatment, being the group of epidemiological polarization.This     fact indicates that a considerable proportion of this group did not receive any benefits from traditional preventive programs. 23n the dmft index, the main component responsible for the values was the decayed component, which represented 89% at 4 years, 82% at 5 years, and 78% at 6 years.This result may indicate that these preschoolers had no access to dental services.
This study demonstrates that children who already had access to dental treatments were those who showed experience with caries, rampant caries, and caries including non-cavitated lesions.This finding indicates that, when using dental services in Brazil, people have an old view of oral diseases that is associated with the treatment of dental caries through its sequelae, the cavity, rather than considering preventive aspects.
The present study confirmed the association between caries and socio-economic characteristics.Epidemiological studies have clearly reported that there is an increase in the risks of early childhood caries associated with socio-economic characteristics, including low income and low educational level. 24,25These associations are likely because lowincome families have material, social, and financial disadvantages that compromise their ability to care for themselves and their children.These families face difficulties in obtaining professional care in health services and do not identify dental problems through preventative care during the early stages of their disease.They have a poor nutritional status, less access to early diagnosis, fewer therapeutic resources, and worse disease prognoses. 25All of these factors lead to a decreased resistance to disease, including oral diseases. 26his study highlights the importance of prevention to combat dental caries.Prevention programs should target specific groups; however, the best strategy depends on several factors, including cultural, economic, and geographic factors.Some strategies include the use of fluoride, chlorhexidine, sealant and xylitol, behavioral changes, social programs, and cultural modification.The most suitable strategy depends on local factors. 27The early identification of high-risk groups and the approaching of behavioral aspects in preventive and educational programs on oral health should be encouraged. 28

Conclusion
Caries prevalence in the primary dentition of children was associated with parental factors, including parents' socio-economic status, behaviors, and attitudes related to oral health.These factors should be considered when planning preventive and educational programs about oral health for children in this age group.

Figure 1 -
Figure 1 -Percentage distribution of children according to the dmft index.

Figure 2 -
Figure 2 -Percentage distribution of decayed, missing and filled teeth in the dmft index, according to age.

Table 1 -
Caries experience of children according to age.

Table 2 -
Number and percentage of children with caries according toparents' educational level, family income, and behavioral variables.

Table 3 -
Multivariate analysis for the presence of caries.