ARTIGO ARTICLE 717
Dental caries in the primary dentition
in public nursery school children
in Juiz de Fora, Minas Gerais, Brazil
Crie dentria na dentio decdua
de crianas assistidas em algumas creches
pblicas em Juiz de Fora, Minas Gerais, Brasil
Isabel Cristina Gonalves Leite 1
Rosangela Almeida Ribeiro 1
1 Faculdade de Odontologia, Abstract The aim of this study was to assess the prevalence of dental caries in the primary den-
Centro Integrado de Sade,
tition and associated variables in low socioeconomic preschool children enrolled in public nurs-
Universidade Federal
de Juiz de Fora. ery schools in Juiz de Fora, Minas Gerais, Brazil. Four public institutions were selected by geo-
Campus Universitrio, graphic criteria (two in the central region and two in the peripheral region). The study popula-
Juiz de Fora, MG
tion comprised 338 children (181 boys; 157 girls) aged 2-6 years old. Dental caries was recorded
36030-330, Brasil.
bel@odonto.ufjf.br using the decayed, missing, and filled teeth (dmf-t) index. Among the examined children, 50.6%
were caries-free. The mean dmf-t index was 2.03. It was higher in the peripheral nursery schools
(p < 0.01). A trend towards a difference between sexes (p = 0.06) was observed. Logistic regression
analysis selected a previous childs visit to dentist (p < 0.001), geographic location of the public
nursery school (p < 0.01), and age (p < 0.01) as predictive variables for the dmf-t index. The study
showed the need for an oral health program for this population, including both curative and
preventive measures in order to achieve the WHO/FDI goals for the year 2000, namely 50% of
children free of caries at age 5-6 years.
Key words Dental Caries; Primary Dentition; Prevalence; Epidemiology
Resumo O objetivo deste estudo foi avaliar a prevalncia de crie dentria em dentio dec-
dua e variveis a ela associadas em pr-escolares, de baixo nvel scio-econmico, assistidos em
creches pblicas da cidade de Juiz de Fora, Minas Gerais, Brasil. Quatro instituies pblicas fo-
ram selecionadas por critrios geogrficos (duas na regio central e duas na regio perifrica). A
populao do estudo compreendeu 338 crianas (181 meninos; 157 meninas) com idade de dois
a seis anos. A crie dentria foi registrada usando o ndice ceo-d. Dentre as crianas examina-
das, 50,6% estavam livres de crie. A mdia do ndice ceo-d foi 2,03, que foi maior na creches
perifricas (p < 0,01), e uma tendncia de diferena entre sexos foi observada (p = 0,06). A anli-
se de regresso logstica selecionou as variveis visita prvia da criana ao dentista (p < 0,001),
localizao geogrfica da creche pblica (p < 0,01) e idade (p < 0,01) como preditoras do ndice
ceo-d. O estudo mostrou a necessidade de um programa de sade bucal para essa populao, in-
cluindo medidas tanto curativas, quanto preventivas, com o objetivo de alcanar as metas da
OMS/FDI para o ano 2000 (50% de crianas livres de crie na faixa etria de cinco a seis anos).
Palavras-chave Crie Dentria; Dentio Primria; Prevalncia; Epidemiologia
Cad. Sade Pblica, Rio de Janeiro, 16(3):717-722, jul-set, 2000
718 LEITE, I. C. G. & RIBEIRO, R. A.
Introduction prevalence in the primary dentition of preschool
children attending public nursery schools in
There is ample evidence that prevalence of den- this city in order to provide data for formula-
tal caries has been declining over the last two tion of oral health programs for this specific
decades in most countries in Western Europe population.
and North America. The reduction in the aver-
age decayed, missing, and filled teeth (dmf-t)
scores has been reported to be between 40% Methods
and 60% in most age groups. The decline in
caries has been associated mainly with the Subjects
widespread availability of fluoride toothpastes
and changes in the pattern and amount of ex- The study was performed in the first semester
trinsic sugar consumption, whereas the in- of 1998 in the city of Juiz de Fora, State of Minas
crease is primarily related to the increase in Gerais, Southeast Brazil, which has had fluori-
consumption of extrinsic sugars, especially su- dated water (0.8mgF/l) since 1983. The study
crose (Sheiham, 1984; Holm, 1990; Freire et al., group comprised 338 preschool children with
1996). Prevalence of dental caries in Brazil still complete primary dentition (181 boys; 157 girls)
constitutes a public health problem, particular- aged 2-6 years old (mean age 4.3 years old) at-
ly in some areas. Data from a national epidemi- tending public nursery schools on weekdays.
ological survey showed a mean dmf-t of 4.84 at The sample included four randomly selected
age 12 years (SESI, 1995). public nursery schools representing 22% of the
Internationally, dental disease in young chil- 18 existing public nurseries in 1998. A house-
dren has been less studied than in older age hold income lower than the Brazilian monthly
groups. Despite poor dental conditions, few epi- minimum wage (R$136,00 or US$75.00) was re-
demiological studies focused on children un- quired for these children to be admitted to
der 6 years of age in Brazil. Freire et al. (1996) such nursery schools. The study sample repre-
assessed dental caries in the primary dentition sented 16.1% of the total population (aged 2-6
of 2,267 preschool children, aged 0-6 years old, years-old) served by these institutions (338/
in Goinia, Gois, attending public (low socioe- 2,100 children). The nurseries were randomly
conomic) and private (high socioeconomic) selected on the basis of their geographic loca-
nursery schools. Caries prevalence was higher tion according to data provided by the local
in public than private nursery school children health authority. The sample included two in-
(p < 0.05). Among children from public nursery stitutions located in the central region of the
schools, the highest dmf-t component was un- city and two located on the periphery. The study
treated decay, while in private nurseries it was design received prior approval by the Ethics
filled teeth. Mattos-Graner et al. (1996) deter- Committee of the School of Medicine at the Fed-
mined the prevalence of dental caries in 322 eral University in Juiz de Fora. Parental consent
Brazilian children aged 6-36 months in Piraci- forms were also obtained. Distribution of the
caba, So Paulo. The earliest ages at which ini- sample by age, sex, and geographic location of
tial and manifest caries were recorded in chil- the public nursery schools is shown in Table 1.
dren were 6-12 months and 13-18 months re-
spectively. Sixty-five per cent of the children Clinical recordings
were caries-free. Seventeen per cent of the af-
fected children showed 46% of the total caries Clinical visual examinations were done on site
lesions, which demonstrates the need for early in daylight by the authors using a mouth mir-
identification of those with a high caries risk. ror. The children had their teeth brushed and
In an epidemiological survey of caries preva- dried with gauze before the examination. Ex-
lence and distribution in 0-36-month-old chil- aminers were calibrated in one nursery school
dren living in Diadema, So Paulo, Brazil, con- before the beginning of the survey. Inter-exam-
ducted by Bnecker et al. (1997), mean dmf-t iner agreement was calculated by the Kappa
per child was 0.16 at one year, 0.87 at two years, coefficient at 0.85. Dental caries (dmf-t index)
and 2.54 at three years of age. Mean dmf-s val- was recorded according to WHO (1994). A tooth
ues for the same groups were 0.17, 1.13, and was considered carious (d component) if there
3.68, respectively. was visible evidence of a cavity, including un-
Oral health conditions of preschool chil- treated dental caries and filled teeth with recur-
dren had never been documented in the city of rent caries. The m component included teeth
Juiz de Fora, Minas Gerais. The current study with indications for extraction due to caries
was thus conducted to investigate dental caries (Freire et al., 1996; Mattos-Graner et al., 1996).
Cad. Sade Pblica, Rio de Janeiro, 16(3):717-722, jul-set, 2000
DENTAL CARIES IN THE PRIMARY DENTITION 719
Table 1
Distribution of preschool children (n = 338) sex and geographic location of the public
nursery schools Juiz de Fora, Minas Gerais, Brazil, 1998.
Age Central region Peripheral region Central and peripheral region
n Male Female n Male Female n Male Female
2 23 47.8% 52.2% 19 62.6% 37.4% 42 50.0% 50.0%
3 31 54.8% 45.2% 20 60.0% 40.0% 51 56.9% 43.1%
4 52 55.8% 44.2% 35 48.6% 51.4% 81 40.5% 59.5%
5 49 34.7% 65.3% 35 48.6% 51.4% 84 63.8% 36.2%
6 52 63.8% 36.2% 28 69.3% 31.7% 80 63.8% 36.2%
Total 207 51.7% 48.3% 131 56.5% 43.5% 338 181 157
Table 2
Caries experience in relation to age of a group of 338 preschool children Juiz de Fora, Minas Gerais, Brazil, 1998.
Age no in groups no (%) caries free Mean dmf-t Mean dmf-t d (Mean SD m (Mean SD f (Mean SD
(years) ( SD) all ( SD) excluding and % of dmf-t) and % of dmf-t) and % of dmf-t)
children caries free children
2 23 32 (76.2%) 0.7 (1.50) 2.9 (1.8) 0.6 (1.3) 86.2% 0.1 (0.6) 13.8%
3 31 33 (64.7%) 1.4 (2.61) 3.9 (3.1) 1.3 (2.5) 91.4% 0.1 (0.6) 8.6%
4 52 37 (45.7%) 1.9 (2.68) 3.5 (2.8) 1.6 (2.5) 82.4% 0.1 (0.3) 2.6% 0.2 (0.9) 14.9%
5 49 37 (44.0%) 2.4 (3.06) 4.3 (2.9) 2.1 (2.7) 87.6% 0.1 (0.6) 5.5% 0.2 (0.7) 6.9%
6 52 32 (40.0%) 2.9 (3.30) 4.8 (8.6) 2.4 (2.8) 80.7% 0.2 (0.8) 7.9% 0.3 (1.0) 11.4%
The criteria used for decay severity was ographic location, and prior visits to dentist.
adapted by the authors from the WHO classifi- The influence of independent variables and the
cation for permanent dentition (FDI/WHO, dmf-t index was established by logistic regres-
1982), after which the very low prevalence was sion analysis.
represented by a dmf-t from 0.1 to 0.7, low
prevalence as dmf-t from 0.8 to 1.6, moderate
from 1.7 to 2.7, high from 2.8 to 4.0, and very Results
high over 4.1.
Data on independent variables were ob- The number of children in each age bracket
tained from the mothers who agreed to partici- and their experience with caries are shown in
pate in the study. The race variable was classi- Table 2. Data from 338 children indicated
fied as white or black. Visit to dentist was de- that 50.6% were caries-free. The proportion of
scribed as the presence of private and/or pub- caries-free children ranged from 76.2% in 2-
lic restorative intervention at any time in the year-old children to 40.0% in six-years-old (Fig-
childs life (data provided by mother and visu- ure 1). Of all the caries-free children (n = 171),
al inspection). Number of times teeth brush 26.9% were from nursery schools in neighbor-
per day in the nursery school was recorded ac- hoods, whereas 73.1% attended nursery schools
cording to information obtained by the school in neighborhoods with relatively higher socioe-
nurse. conomic status. Analyzing the proportion of
Data were processed and analyzed using caries-free children by geographic location, the
EpiInfo version 6.0 and SPSS 6.0 for Windows. data revealed a statistical difference between
Comparisons between groups were made us- central and peripheral nursery schools (p <
ing 2 test, analysis of variance was applied for 0.01). For the sample as a whole, the dmf-t in-
the study of dmf-t index related to race, sex, ge- dex was 2.03. Mean dmf-t was lower in two-
Cad. Sade Pblica, Rio de Janeiro, 16(3):717-722, jul-set, 2000
720 LEITE, I. C. G. & RIBEIRO, R. A.
Figure 1 2.8) than girls was 0.80. In addition, the num-
ber of daily brushings at nursery school was in-
Percentages of children caries free and caries positive in relation to age (=338). versely proportional to dmf-t.
80
dmf-t = 0 Discussion
70
dmf-t 0
The present study demonstrated early initia-
60
tion of tooth decay in Brazilian preschool chil-
50 dren, confirming previous observations (Freire
et al., 1996; Mattos-Graner et al., 1996; Bnecker
40
et al., 1997). The results also demonstrated a
30 significant relationship between age and caries.
This relationship had been shown in both
20 younger (Freire et al., 1996; Mattos-Graner et
10
al., 1996; Bnecker et al., 1997) and older chil-
dren (Dini et al., 1996; Moreira et al., 1996; Vigild
0 et al., 1996).
2 years-old* 3 years-old** 4 years-old 5 years-old 6 years-old
Mean dmf-t and the proportions of chil-
dren with caries are similar to those observed
in another group of Brazilian preschool children
* indicates statistically significant difference (p < 0.01) attending public and private nursery schools:
** indicates statistically significant difference (p < 0.05) dmf-t = 2.03 (Freire et al., 1996). The rates are
higher than those found amongst nursery school
children in Nairobi, Kenya: dmf-t = 1.88 (Masi-
ga & Holt, 1993). However, they are lower those
years-old (0.7 1.50) and higher in six-years- from in studies in Hong Kong: dmf-t = 2.93
old (2.9 3.30); these differences were statisti- (Wei et al., 1993); Kuwait: dmf-t = 6.2 (Vigild et
cally significant (Table 2). The dmf-t component al., 1996), and San Fernando, Spain: dmf-t =
values shown in Table 2 show that the index 3.19 (Romero-Ruiz et al., 1996).
consisted largely of decayed teeth (d compo- Analysis of each component in the dmf-t
nent), which constituted 0.6 of the total in two- index showed a marked influence of the D com-
years-old, 1.3 in three-years-old, 1.6 in four- ponent, as also observed in other surveys (Wei
years-old, 2.1 in five-years-old, and 2.6 in six- et al., 1993; Freire et al., 1996; Mattos-Graner et
years-old. Analysis of variance showed no signif- al., 1996; Bnecker et al., 1997). In other words,
icant differences in caries scores between races it appears that the pressing need for dental
or sexes (p = 0.62 and 0.06, respectively). How- treatment in the primary dentition reflects the
ever, geographic location of the public nursery current economic and practical difficulties
school and the childs prior visit to dentist within the health services system administered
showed a highly significant influence (Figure 2). by local health authorities, supporting the con-
Table 3 presents odds ratios calculated by clusions reported by Petersen et al. (1994).
using b coefficient obtained during stepwise These results showed a low percentage of
logistic regression. Data indicated that children children with a high number of dental caries.
with at least one prior visit to the dentist were Of the 338 children, 18.3% had a very high dmf-t
12 times more likely to be in the higher dmf-t (n = 62), and 6.2% had a high dmf-t (n = 21).
group (dmf-t > = 4) than the other, holding all Three per cent of the affected children had
other variables constant. Geographic location dmf-t > 10. These results demonstrated the
showed a similar strong effect in the model (i. e., need for early identification of children at high
children attending peripheral nursery schools risk of caries, as suggested by other studies
were almost 4 times more likely to have a high- (Mandel, 1989; Wei et al., 1993; Freire et al.,
er dmf-t than were those attending central 1996). In addition, childrens prior experience
nursery schools). Table 3 also shows that if the with caries has often been shown to be the sin-
variables with p-values ranging from 0.05 to gle best predictor of future dental disease (S-
0.10 were kept in the final prognostic model, mundsson et al., 1997). Our results indicated
sex and number of times teeth were brushed the influence of prior dental restorative treat-
per day in the nursery school would have been ment on a higher dmf-t score, when all other
included. Data suggested that the overall prob- variables remained constant ( Table 3). It ap-
ability of boys having a higher dmf-t (above pears that the sort of dental care offered to
Cad. Sade Pblica, Rio de Janeiro, 16(3):717-722, jul-set, 2000
DENTAL CARIES IN THE PRIMARY DENTITION 721
Figure 2
Dmf-t index by race (p = 0.62), sex (p = 0.06), geographic location of the nursery school (p < 0.01), and a previous
childs visit to dentist (p < 0.001).
16 16
14 14
12 12
10 10
8 8
6 6
4 4
2 2
0 0
white black male female
16 16
14 14
12 12
10 10
8 8
6 6
4 4
2 2
0 0
peripheral region central region previous visit to dentist no previous visit to dentist
Table 3
Odds ratios with 95% lower and upper confidence bounds (L95, U95) of increased risk.
Predictors OR L95 U95 p-valor
Previous visit to dentist 12.50 5.58 26.31 p<0.001
Children attending peripheral nursery schools 3.52 1.97 6.30 p<0.001
Age 1.40 1.11 1.75 p<0.01
Sex 1.77 1.01 3.06 p = 0.06
Number of daily toothbrushing 1.15 1.02 1.35 p = 0.09
Cad. Sade Pblica, Rio de Janeiro, 16(3):717-722, jul-set, 2000
722 LEITE, I. C. G. & RIBEIRO, R. A.
these children is insufficient to promote their survey conducted in So Paulo (NEPESS, 1999).
oral health, as related by Freire et al. (1996). In 1998, the mean dmf-t was 2.94 (2.90-2.98)
Forty per cent of children were caries-free and 39% 5-year-old children were in the caries-
at age six years. This rate is still lower than the free group. However, this percentage was higher
first oral health goal of FDI/WHO (1982) for the in private (59%) as compared to public schools
year 2000 (i. e. 50% of children free of caries at (38%).
this age). However, this rate is better than that In light of these results from our survey, one
of Brazilian preschool children attending public can conclude that implementation of an oral
nursery schools in Goinia (Freire et al., 1996). health program for children attending public
It is also better than those observed among chil- nursery schools should be a high priority. Such
dren from other countries, where rates ranged a program should include not only preventive
from 9% to 34% (Holbrook, 1993; Petersen et al., measures but also curative treatment of the af-
1994; Romero-Ruiz et al., 1996; Vigild et al., fected primary teeth, in order to allow for per-
1996). Taking into account the geographic lo- manent teeth to erupt under more favorable
cation of public nursery schools, we note that conditions. The educational program should
26.9% of the caries-free children were attend- emphasize prenatal orientation for groups of
ing peripheral nursery schools, whereas 73.1% pregnant women as well as professional train-
were attending nursery schools in more central ing for preventive attention to babies (0-3
and relatively more affluent neighborhoods. years) in order to encourage healthy oral habits
This pattern appeared in the epidemiological during this period.
References
BNECKER, M. J. S.; GUEDES-PINTO, A. C. & WAL- em escolares de localidade urbana da regio Sudes-
TER, L. R. F., 1997. Prevalncia, distribuio e grau te do Brasil. Revista de Sade Pblica, 30:280-284.
de affeco de crie dentria em crianas de 0 a NEPESS (Ncleo de Estudos e Pesquisas de Sistemas
36 meses de idade. Revista da Associao Paulista de Sade), 1999. Levantamento Epidemiolgico
de Cirurgies-Dentistas, 51:535-540. em Sade Bucal Estado de So Paulo, 1998. So
DINI, E. L.; ROZATO-FOSCHINI, A. L.; CASARINI-DE- Paulo: Secretaria de Estado de Sade de So Paulo.
MENDONA, F. C.; DE-NARDO, G.; GARDIM- PETERSEN, P. E.; DANILA, I.; DALEAN, A.; GRIVU, O.;
ABBAD, M. T. & MARSON-SECCHEV-FRAIS, R. IONITA, G.; POP, M. & SAMOLIA, A., 1994. Oral
L., 1996. Changes in dental caries prevalence of health status among school children in Romania,
school children in Araraquara, SP, Brazil. Interna- 1992. Community Dentistry and Oral Epidemiolo-
tional Dental Journal, 46:82-85. gy, 22:90-99.
FDI (Fdration Dentaire Internationale)/WHO (World ROMERO-RUIZ, M. M.; SERRANO-GONZALEZ, A.;
Health Organization), 1982. Global goals for oral ALVAREZ-OSORIO, G. S.; M. R. & ZAFRA-MEZCUA,
health by the year 2000. International Dental Jour- J. A., 1996. Prevalence of dental caries in a 6-year
nal, 32:74-77. old population from San Fernando. Atencin Pri-
FREIRE, M. C. M.; MELO, R. B. & SILVA, S. A., 1996. maria, 18:431-435.
Dental caries prevalence in relation to socioeco- SMUNDSSON, S. R.; SLADE, G. D.; SPENCER, A. J.
nomic status of nursery school children in Goi- & DAVIES, M. J., 1997. The basis for clinicians
nia-GO, Brazil. Community Dentistry and Oral caries risk grouping in children. Pediatric Den-
Epidemiology, 24:357-361. tistry, 19:331-338.
HOLBROOK, W. P., 1993. Dental caries and cariogenic SESI (Servio Social da Indstria), 1995. Estudo Epi-
factors in pre-school urban Iceland children. demiolgico sobre Preveno da Crie Dental em
Caries Research, 27:431-437. Crianas de 3 a 14 Anos. Braslia: SESI.
HOLM, A. K., 1990. Diet and caries in high-risk groups SHEIHAM, A., 1984. Changing trends in dental caries.
in developed and developing countries. Caries International Journal of Epidemiology, 13:142-147.
Research, 24:44-52. VIGILD, M.; SKOUGAARD, M.; HADI, R. A.; AL-ZAABI,
MANDEL, I. D., 1989. Preface. In: Cariology (E. New- F. & AL-YASSEEN, I., 1996. Dental caries and den-
brun, ed.), 3rd Ed. Chicago: Quintessence. tal fluorosis in 4-, 6-, 12- and 15-year-old children
MASIGA, M. A. & HOLT, R. D., 1993. The prevalence of in kindergartens and public schools in Kuwait.
dental caries and gingivitis and their relationship Community Dental Health, 13:47-50.
to social class among nursery-school children in WEI, S. H. Y.; HOLM, A. K.; TONG, L. S. M. & YUE, S.
Nairobi, Kenya. International Journal of Pediatric W. H., 1993. Dental caries prevalence and related
Dentistry, 3:135-140. factors in 5-year-old children in Hong Kong. Pe-
MATTOS-GRANER, R. O.; RONTANI, R. M. P.; GAVIO, diatric Dentistry, 16:116-119.
M. B. D. G. & BOCATTO, H., 1996. Caries preva- WHO (World Health Organization), 1994. WHO Glob-
lence in 3-36-month-old Brazilian children. Com- al Data Bank GODB: World Day of Oral Health.
munity Dental Health, 13:96-98. Geneva: WHO.
MOREIRA, B. H. W.; PEREIRA, A. C. & OLIVEIRA, S. P.,
1996. Avaliao da prevalncia de crie dentria
Cad. Sade Pblica, Rio de Janeiro, 16(3):717-722, jul-set, 2000
