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Low Maternal Schooling and Severity of in Brazilian Preschool Children
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pyrig No Co t fo rP ORIGINAL ARTICLE ub lica tio n te ss e n c e Dental Caries
Jefferson Traeberta/Luana do Amaral Guimarãesa/ Elaine Zapelini Tartari Durantea/Ana Claudina Prudêncio Serratinea
Purpose: The aim of this study was to identify the prevalence and severity of caries and of early childhood caries (ECC) in preschool children from the municipality of Capivari de Baixo, Brazil. Furthermore, the aim was to ascertain the association between these prevalences and the level of maternal schooling. Materials and Methods: A cross-sectional study was performed involving all children aged 3 to 5 years enrolled in all municipal schools of Capivari de Baixo, Brazil. The clinical information was obtained using the World Health Organization criteria. For ECC, it was observed if the child presented with lesions with acute evolution, whitening clinical aspect and softened consistency. Non-clinical data were obtained by means of interviews with the child’s mothers, by investigating the child and through questions relating to the maternal age, the maternal level of schooling and the time of weaning. Tests of association were performed using the chi-square test followed by unconditional multiple logistic regression analysis to test the independence of the association between the outcomes and the explanatory variables. Results: The prevalence of caries was 64.3%, the mean dmft was 1.24 and the prevalence of ECC was 4.9%. A child was more likely to present with severe caries (dmft 2) if aged 47 months or above. Low maternal schooling made the occurrence of both severe caries and ECC more likely. Conclusions: The population that was studied presented levels of oral health better than those found in other Brazilian population groups, although groups remain with a high severity of caries associated with low maternal schooling. Key words: dental caries, early childhood caries, infectious disease, schooling, socioeconomic status Oral Health Prev Dent 2009; 7: 39–45.
ental caries is a chronic disease that causes discomfort and generates an impact on the quality of life of the affected individuals. Despite remarkable reduction in the prevalence of dental caries, this is still a highly prevalent disease among children who are socially disadvantaged (Vargas and Ronzio, 2006). This also requires special attention due to its high prevalence and severity in specific population groups (Petersen, 2003) such as children of younger age groups.
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Dental Public Health Research Group, Universidade do Sul de Santa Catarina, Avenida José Acácio Moreira, 787, 88704-904 Tubarão, SC, Brazil.
Correspondence: Jefferson Traebert, Avenida José Acácio Moreira, 787, 88704-904 Tubarão, SC, Brazil. Tel/Fax: +55 48 3621-3363. Email:
[email protected]
Vol 7, No 1, 2009
Submitted for publication: 13.01.08; accepted for publication: 05.02.08.
Striking examples of this situation can be given when one compares the level of attention with oral health in the primary dentition in relation to the permanent dentition. Another example is the higher prevalence and severity of caries in the primary dentition, especially in what is referred to as the early childhood caries (ECC) (Schroth et al, 2007). The term ECC is used to determine the presence of a carious lesion in preschool children. It is defined as the occurrence of dental caries in the first 3 years of life (Ismail, 1998). This term defines the age of the group affected, characterising it as a disease of rapid development that affects tooth surfaces that are normally free of caries (Horowitz, 1998). The ECC begins with a discrete demineralisation in the primary maxillary incisors, but can later progress to involve primary molars and canines. Those affected often suffer from a reduced oral health-related 39
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A cross-sectional study was performed involving children aged 3 to 5 years (N = 387) enrolled in 10 municipal schools of Capivari de Baixo, Brazil during the year 2001. The municipality is found in the southern region of the southern Brazilian state of
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MATERIALS AND METHODS
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quality of life when contrasted with their caries-free peers (Schroth et al, 2007). The destructive characteristics of this type of caries, or even a high severity of the disease, as seen from an excessive number of the affected teeth at an early age, imply that it requires special attention. Consequently, some researchers have leaned towards studies that allow the identification of the predictors of dental caries among the population, which enables the efficient implantation of public policies to promote oral health of the more vulnerable groups, thus improving their quality of life. Petersen (2003) outlined that the greatest burden of oral disease is on those who are disadvantaged and socially marginalised. Dental caries remain as an important oral problem in many communities, particularly among underprivileged groups in the developed and in the developing countries. According to Petersen (2003), sociobehavioural and environmental factors play an important role in oral disease and health, and this has been demonstrated in several reports. The social, economic, political and cultural determinants of health are considered to be significant, and better health can be achieved by reducing poverty. The study of the association between health indicators and socioeconomic status has shown, in general, a directly proportional relationship; that is, the lower the socioeconomic status the worse the health indicators (Lynch and Kaplan, 2000). Among the varied possibilities for the use of socioeconomic indicators, the level of maternal schooling has been used as one of the best predictors of a child’s health, mainly in underdeveloped countries (Victora et al, 1992). Studies have shown that the degree of schooling of the child’s guardian, especially the level of schooling of the mother, appears to be a risk factor for dental caries in children (Saito et al, 1999; Peres et al, 2000). Therefore, the objective of this study was to identify the prevalence and severity of caries and of ECC in schoolchildren aged 3 to 5 years in the municipality of Capivari de Baixo, Brazil. The second objective was to identify any eventual association between these prevalences and the level of maternal schooling.
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pyrig No Co t fo rP ub lica tio Santa Catarina, and it has a population of 18,561 t inhabitants. ess c e n en Clinical information concerning the oral condition was obtained by means of the dmft index (number of carious teeth, missing teeth due to caries and restored teeth in the primary dentition) according to the World Health Organization (WHO, 1997) criteria. To obtain the prevalence of ECC, it was observed if the child had acute caries, whitening clinical aspect and a softened consistency, with extensive flat white patches, covering the cervical face of the teeth, reaching the crown (Feldens et al, 2007). Also, lesions with such characteristics, although darker due to the application of silver diamine fluoride, were counted. Non-clinical data were obtained by means of interviews with the mothers, focusing on the age of the child and the mother (both dichotomised in the median of the age distribution), the mother’s level of schooling (up to and more than 8 completed years of study) (IBGE, 2001) and the time of weaning (up to and more than 4 months). The mothers were interviewed at the time when they picked up their children from the school. When this was not possible, the interviews were carried out at their home. The study team comprised two examiners previously trained and calibrated with the aim of reducing discrepancies of interpretation in the diagnoses. The process of training and calibration of the examiners comprised a theoretical stage with 4 h of discussion regarding the criteria, using clinical slides illustrating the different situations that are likely to be encountered. The second stage comprised a clinical exercise to establish the criteria, in which six children within the age range of the study were examined in a neighbouring municipality, by both the examiners and a standard examiner. The calibration itself was carried out by clinical examination of ten children in the age range of the study by the two examiners as well as the standard examiner. The kappa statistics were calculated on a tooth-by-tooth basis for both intraexaminer and interexaminer calibration (Peres et al, 2001). The lowest kappa values found were: 0.75 for tooth 65, interexaminer calibration; 0.70 for tooth 55, intraexaminer 1 calibration; and 0.75 for tooth 65, intraexaminer 2 calibration. For the examinations, dental instruments were previously packaged and sterilised in an autoclave, and then transferred to metal containers that remained sealed until the time of the examinations. These procedures were rigorously observed for each child examined. A total of 10% of the sample was examined twice by each examiner, with the objective of confirming the diagnostic reproducibility by the Oral Health & Preventive Dentistry
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pyrig No Co t fo r P et al Traebert ub lica tio Table 1 Descriptive statistics of dmft index and components and ECC prevalence in preschool children of Capivari de t ess c e n Baixo, Brazil, during 2001 en
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Decayed (d)
Mean %
Missing (m)
1.10 88.7
0.02 1.6
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Statistical data
Filled (f)
dmft
dmft 2
ECC
0.12 9.7
1.24 100.0
– 27.9
– 4.9
dmft: decayed, missing and filled teeth.
Table 2 Prevalence of severe caries (dmft 2), ECC and associated factors in preschool children of Capivari de Baixo, Brazil, during 2001 dmft 2
Variables
Child’s age (median) 47 months > 47 months Child’s gender Male Female Mother’s age (median)** 28 years > 28 years Mother’s schooling** 8 years > 8 years Time of weaning** 4 months > 4 months
Total N (%)
No (%)
Yes (%)
135 (72.6) 88 (54.6)
41 (27.4) 97 (45.3)
186 (53.6) 161 (46.4)
119 (71.2) 131 (72.7)
48 (28.8) 49 (27.3)
167 (48.1) 180 (51.9)
112 (67.9) 124 (75.1)
53 (32.1) 41 (24.9)
165 (50.0) 165 (50.0)
77 (62.1) 158 (67.2)
47 (37.9) 46 (22.6)
124 (37.8) 204 (62.2)
125 (75.7) 109 (67.3)
40 (24.3) 53 (32.7)
165 (50.5) 162 (49.5)
P*
ECC
Total N (%)
No (%)
Yes (%)
179 (96.2) 151 (93.8)
7 (3.8) 10 (6.2)
186 (53.6) 161 (46.4)
158 (94.6) 172 (95.5)
9 (5.4) 8 (4.5)
167 (48.1) 180 (51.9)
156 (94.5) 157 (50.2)
9 (5.4) 8 (4.5)
165 (50.0) 165 (50.0)
113 (91.1) 198 (97.0)
11 (8.9) 6 (3.0)
124 (37.8) 204 (62.2)
156 (94.5) 157 (95.1)
9 (5.5) 8 (4.9)
165 (50.5) 162 (49.5)
0.008
P*
0.292
0.753
0.684
0.143
0.803
0.003
0.019
0.089
0.833
*Chi-square test; **missing information.
examiners during the process of clinical data collection. The children were chosen at random at the end of each shift. A pilot study was performed in the neighbouring municipality, involving 10% of the sample total (N = 38) with the objective of testing the proposed methodology. No readjustment was found to be necessary. The data of the results were inputted in the SPSS version 13.0 (SPSS, IL, USA) and were analysed in descriptive terms. The tests of association were performed using the chi-square test. The level of significance established was P < 0.05. Unconditional multiple logistic regression was carried out using the stepwise method (Hosmer and Lemeshow, 1989) to test the independence of the association between the outcomes (severe caries in the primary dentition (arbitrarily considered as dmft 2) and the Vol 7, No 1, 2009
prevalence of ECC) with the explanatory variables studied. All of the variables with a value of P < 0.20 in the univariate analysis were entered in models by the order of significance, and only those with P < 0.05 were maintained in the final model that was adjusted for the variables studied. The research project was examined and approved by the education and health authorities of the municipality of Capivari de Baixo and by the Committee for Ethics in Research of the Universidade do Sul de Santa Catarina, Brazil.
RESULTS The total number of children examined was 347, giving a response rate of 89.7%. The results of the 41
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OR adjusted (CI 95%)
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Child’s age (median) 47 months > 47 months Child’s gender Male Female Mother’s age (median)** 28 years > 28 years Mother’s schooling** 8 years > 8 years Time of weaning** 4 months > 4 months
OR crude (CI 95%)
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Variables
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Table 3 Association between demographic characteristics and severe caries (dmft 2) – regression model in Capivari de Baixo, Brazil, during 2001
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pyrig No Co t fo rP ub lica t unconditional logistic ion te ss e n c e P 0.008
1 1.89 (1.17; 3.03)
1 1.97 (1.20; 3.25) 0.753
0.358
1.08 (0.67; 1.72) 1
1.26 (0.77; 2.08) 1 0.143
0.049
1.43 (0.88; 2.31) 1
1.65 (1.00; 2.74) 1 0.003
0.002
2.10 (1.28; 3.42) 1
2.18 (1.32; 3.60) 1 0.089
*
1 1.52 (0.94; 2.47)
*
Adjusted by demographic characteristics; *removed from the model for loss of significance; Hosmer–Lemeshow test (P = 0.835); **missing information.
Table 4 Association between demographic characteristics and ECC – unconditional logistic regression model in Capivari de Baixo, Brazil, during 2001 Variables Child’s age (median) 47 months > 47 months Child’s gender Male Female Mother’s schooling* 8 years > 8 years
OR crude (CI 95%)
P
OR adjusted (CI 95%)
0.292 1 1.69 (0.63; 4.56)
0.281 1 1.73 (0.64; 4.71)
0.684 1.22 (0.46; 3.25) 1
0.680 1.27 (0.47; 3.40) 1
0.019 3.21 (1.16; 8.96) 1
P
0.025 3.22 (1.16; 3.96) 1
Adjusted by demographic characteristics; Hosmer–Lemeshow test (P = 0.920); *missing information.
duplicate examinations showed kappa values of 0.75 for examiner 1 and 0.70 for examiner 2, both for tooth 65. The prevalence of children without caries was 35.7% (confidence interval, CI 95% 30.7; 40.7). The mean dmft found was 1.24 (CI 95% 1.00; 1.48), and the components of the indicator are presented in Table 1. A little over one-quarter of the children (27.9%) exhibited dmft values that were equal to or above 2, and for this reason this value was taken as the cut-off point for the studies of caries severity. 42
In addition, the presence of ECC was used to the same end, observed in 4.9% (CI 95% 3.8; 6.0) of the children studied. The results of the association studies showed that a greater age of the child (P = 0.008) and low maternal schooling (P = 0.003) were associated with the prevalence of severe caries. Furthermore, low maternal schooling was also seen to be associated with the prevalence of ECC (P = 0.019) (Table 2). The results of the unconditional multiple logistic regression analyses are presented in Tables 3 and 4. It was found that when the child was over 47 Oral Health & Preventive Dentistry
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The high response rate that was obtained, the process of the examiners’ calibration and the high level of diagnostic reproducibility that was achieved during the process of data collection suggest good internal validity of the study. Of the 347 children examined the prevalence of caries was 64.3%, a result higher than that expected according to WHO (1995), which predicted a prevalence of 50.0% for the children in this age group. However, this prevalence was lower than that observed in other studies undertaken in Brazilian cities (Couto et al, 2005; Lucas et al, 2005; Rihs et al, 2005). The mean values for dmft determined in these studies were also greater when compared with the values that were obtained from Capivari de Baixo. The prevalence of ECC found in this study (4.9%) was practically half of that reported by Couto et al (2005) and Ribeiro et al (2005) in Brazilian cities and about a quarter of that reported by Livny et al (2007) in a severely deprived, previously nomadic tribe, dwelling in the eastern outskirts of Jerusalem. In this study, it was observed that older children (> 47 months) resulted in almost double the chance of presenting with severe caries, when compared with children of a younger age. In theory, this could be explained by the presence of teeth for a longer time in the oral cavity, resulting in an increased risk of exposure to a cariogenic environment. Despite the growing use of substitutes for breastfeeding allied with early weaning, which was reported as a predisposing factor for caries (Tinanoff and O’Sullivan, 1997; Dini et al, 2000), the findings of the present study corroborate those of Jin et al (2003) and Iida et al (2007) in which the relationship between the time of weaning and ECC was not significant.
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months of age there was a greater chance of the child presenting with severe caries (odds ratio, OR = 1.97 [CI 95% 1.20; 3.25]) (P = 0.008) when compared with individuals of a younger age. The age of the mother exhibited a borderline association (OR = 1.65 [CI 95% 1.00; 2.74]) (P = 0.049) considering mothers over the age of 28 years as the reference group. On the other hand, the lower maternal schooling resulted in a greater chance of developing both severe caries (OR = 2.18 [CI 95% 1.32; 3.60]) (P = 0.002) and ECC (OR = 3.22 [CI 95% 1.16; 8.96]) (P = 0.025) when compared with the group that had more maternal schooling.
pyrig No Co t fo r P et al Traebert ub lic A lower degree of maternal schooling was seen toatio te caries, n be associated with the prevalence of severe ss e n c e increasing the chance of its occurrence more than twofold, and with the prevalence of ECC. In this case, the possibility of its occurrence was increased more than threefold. This study corroborates the suggestion of a directly proportional relationship between socioeconomic status and health indicators (Lynch and Kaplan, 2000) that are included in the dental caries study (Traebert et al, 2001; Peres et al, 2005). Victora et al (1992) have already described maternal schooling as one of the best predictors of health in children, mainly in the underdeveloped countries. National and international studies involving indicators of oral health have also demonstrated this association (Saito et al, 1999; Peres et al, 2000). Freire et al (1996) found a greater prevalence of caries among preschool children in public and in community crèches with low socioeconomic status, in comparison with the children from private crèches of higher socioeconomic status. A study conducted in the United Arab Emirates highlighted the influence of the low level of maternal schooling and of the low socioeconomic status on the experience of caries in children (Hashim et al, 2006). The authors found a dmft of 9.2 among 5-year-old children with the caries component corresponding to 91% of this. In the United Kingdom, children with a higher socioeconomic status presented a dmft of not more than 2.4, at the same age with 60% of them without the disease (Pitts et al, 2003). In Jerusalem, caries was significantly associated, according to univariate analysis, with four factors: children’s age, family size, mothers’ level of education and mothers’ dental appearance (Livny et al, 2007). It should be emphasised that, while the population that was studied exhibited better levels of oral health than other Brazilian population groups, there remain groups with high caries prevalence. The results of this study show that inequalities remain when a socioeconomic factor, such as the level of schooling of the mother, is identified as a risk factor for the occurrence of severe degrees of dental caries in their children. In fact, the association between low maternal schooling and higher indices of severe caries demonstrates the growing inequality in health determinants (WHO, 1995) related to oral health. In this context, the WHO highlighted the high relative risk of oral disease related to sociocultural determinants such as poor living conditions and low education level (Petersen, 2003). Improving the oral health conditions of the children studied requires going beyond the mere recognition 43
The authors thank Dr K Peres for helping in the statistical analyses of the data.
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ACKNOWLEDGEMENT
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It can be concluded that although the population studied here presented levels of oral health superior to those found among other Brazilian population groups, there remain groups with a high severity of caries. Such a condition is associated with low maternal schooling.
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• At the individual level: specific measures of intensive fluoride therapy and atraumatic restorative technique. • At the level of social groups: measures such as universal access to a potable and fluoridated water supply and fluoridated dentifrice, and health education. • At the level of economic models: the guarantee of public policies for health and quality education provision to the whole population, which would mean taking action against the social determinants of the health–disease process.
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that low maternal schooling may represent low economic status, or even that such mothers do not have access to information concerning essential care for the maintenance of their children’s oral health. Rather, it is necessary to recognise that an individual’s health status is the result of the structure of the society and of the social determinants of the health–disease process (Paim and Almeida Filho, 2000) including the schooling of the population. It is fundamental to understand the oral health– disease phenomenon as an expression of lifestyle and life conditions. These factors can explain the epidemiological profile of a population (Possas, 1989). In agreement with this suggestion, Castellanos (1991) indicated several opportunities and intervention strategies to deal with the health–disease process in the population: (i) at the individual or personal level, by means of high-risk strategies; (ii) at the level of social or private groups, by means of population strategies; and (iii) at the level of economic or general space models, by means of public policies. Applying this idea to the situation under investigation, the following can be suggested.
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