Factors predisposing to early childhood caries (ECC) in children of pre-school age in the City of Zagreb, Croatia

Abstract

The aim of this study was to investigate factors predisposing to early childhood caries (ECC) in pre-school children in the city of Zagreb, Croatia. The investigation was carried out on the sample of 145 children (77 boys and 68 girls) aged between 2 and 5 years, including clinical examination of dental status and survey on the habits among the parents. The overall prevalence of ECC was 30%: in girls it was 25%, and in boys 48%. The study on the risk factors was designed as a classic case-control study. The mean value of dmfs index among the cases amounted to 8.6, in comparison to 5.2 in the control group (p<0.05). Bottle-feeding did not represent a significant risk, but night consumption of sweet beverages after first 24 months and the lack of introduction of teeth-brushing habit after first 24 months did (p < 0.001 for both predictors). The study revealed the importance of early introduction of teeth-brushing and giving up the nightly consumption of sweet beverages in prevention of ECC.

Full text

Manuscript title:
Factors Predisposing to Early Childhood Caries (ECC) in Children of
Pre-School Age in the City of Zagreb, Croatia
Authors:
O. Lulić-Dukić, H. Jurić, W. Dukić and D. Glavina
Department of pedodontics, Faculty of Dentistry, University of Zagreb, Croatia
Running head:
Risk factors for ECC in children
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A B S T R A C T
The aim of this study was to investigate factors predisposing to early
childhood caries (ECC) in pre-school children in the city of Zagreb, Croatia. The
investigation was carried out on the sample of 145 children (77 boys and 68 girls) aged
between 2 and 5 years, including clinical examination of dental status and survey on the
habits among the parents. The overall prevalence of ECC was 30%: in girls it was
25%, and in boys 48%. The study on the risk factors was designed as a classic case-
control study. The mean value of dmfs index among the cases amounted to 8.6, in
comparison to 5.2 in the control group (p<0.05). Bottle-feeding did not represent a
significant risk, but night consumption of sweet beverages after first 24 months and the
lack of introduction of teeth-brushing habit after first 24 months did (p<0.001 for both
predictors). The study revealed the importance of early introduction of teeth-brushing
and giving up the nightly consumption of sweet beverages in prevention of ECC.
Introduction
Caries, the most common pathological feature in modern populations, has
been reported as early as during the first several years of child's life. Early caries
usually presents as a localized destruction of the firm, mineralized dental tissue which
involves deciduous teeth, most commonly maxillary incisors. It is a rampant form of
caries, with a very poor prognosis unless the therapy is started during the very early
stage of the pathological process (1). After the year of 1994, and the conference of the
Center for Disease Control (CDC), it has been recommended to designate such clinical
finding as the "early childhood caries" (ECC), since many epidemiological
investigations repeatedly showed that baby bottle, night-feeding and sweet beverages
are not the only etiological factor predisposing to early caries in children, which has
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earlier been widely accepted as a rule (2). Statistical data on the prevalence of ECC
indicate that in European countries it ranges between 7.3% and 12% among two-year-
old children, while among three-year-olds the share increases up to 28% (1,3).
The aim of this study was to investigate the prevalence of ECC among
children of one childrengarden in the City of Zagreb. The goal was to correlate the
clinical findings and the intensity of dental caries with nutritional habits of investigated
children, previous history of breast-feeding, level of oral hygiene and level of health
education of children and their parents.
Subjects and methods
The investigation was carried out on the sample of 145 children (77 boys
and 68 girls) aged between 2 and 5 years, all of them affiliated to kindergarden
"Srednjaci" in Zagreb, Croatia. Clinical examination included the evaluation of the
dental status. The results of the intensity of caries were expressed through the
Decayed, Missing and Filled Surface (dmfs) Index (4). The examination was carried
out using the classic dental probe and the mirror on the daily light. Two independent
investigators were well-trained specialists in pedodontics and were previously
calibrated. The diagnostic criterion for ECC was that at least two of four maxillary
incisors had labiopalatal caries lesions progressed beyond the white or brown spots to
cavitation. The data on potential risk factors for the disease were obtained through a
simple survey. The control group was the only one with no ECC cases present. Each
parent answered, in writing, to the open-end questions concerning the present bottle-
feeding, the age at which their child gave up bottle-feeding, the present drinking of
sweet beverages (milk with sugar, tea or juice) during the night, the age at which their
child gave up that habbit, and the age at which their child started brushing the teeth
regularly.
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The study on the risk factors was designed as a classic case-control
(retrospective) study. Before the statistical analysis subjects were divided in two
groups: 55 with ECC, and 90 healty control. Statistical analysis of the results included
χ2- test with Yates correction for 2x2 cross-tabulation analysis. In the situation of
small frequention (<5) in cells of table were used the Fischer’s exact test. Differences
between groups were established by analysis of variance (ANOVA). Differences was
confirmed when p < 0.05 (bolded numbers).
Results
Table 1 presents the results of the study. The prevalence of ECC in our
sample of pre-school children was 30% (the figure in girls was 25%, and in boys 48%).
It can be noted that several statistically very significant differences between the group
of ECC cases and the control group were noted. Primarily, the mean value of dmfs
index among the cases amounted to 8.6, in comparison to 5.2 in the control group
(p<0.05). Regarding the gender-related differences, it has been shown that boys are
more likely to be among the cases than controls, i.e. that the condition affects children
of male gender more frequently (p<0.05). This effect, however, might be an indirect
consequence of higher prevalence of other predisposing factors in boys, which is
discussed in the last section of this paper.
The analysis of bottle-feeding as a potential predisposing factor revealed
that it was, at present, significantly more frequent in control group rather that in the
group of affected children (p<0.05). However, due to relatively small number of
children who were presently bottle-fed, the similar analysis was undertaken among
those who gave up the habit. It has been shown that the share of children who gave up
bottle-feeding during first 24 months was almost identical in both group (45.8%).
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Therefore, it is reasonable to conclude that bottle-feeding does not represent a risk for
developing ECC.
The share of the children who are still consuming sweet beverages during
the night is very similar in both groups, but the numbers were again too small to
warrant firmer conclusions. The analysis of the time of giving up that habit showed
statistically very significant difference among the groups: 56.5% of children without
ECC stopped it during first 24 months, in comparison to only 19.5% of children with
ECC (p<0.001).
Another very significant difference between the two groups was noted
when analysing the age at which the habbit of teeth-brushing was introduced and
continued regularly. In the group of ECC cases, only 3.6% started brushing their teeth
regularly during first 24 months of their lives. In the control group, the corresponding
proportion was 45.6% (p<0.001).
Discussion
ECC remains a significant problem in both industrialized and less
developed countries. It is frequent among minorities and immigrants in western
countries (5-7). The wide spectrum of discussed predisposing factors ranges from
socio-economic status of the family in which the child is being brought up, education
of the parents, cultural values, ethnicity, nutritional and hygienic habbits, to the number
of parents raising up the child (single- or two-parent-family) (8-10).
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Similarly to other types of caries, ECC is caused by Streptococcus mutans
which digests food carbohydrates and generates strong acids which reduce pH-value
predisposing to destruction of firm dental tissues, especially upper incisors. The
possible pathogenetic mechanism in pre-school hildren might involve infections with
cariogenic bacteria (Streptococcus mutans and Lactobacillus), undeveloped immune
system, specific nutritional habits in early childhood and introduced behavior regarding
oral hygiene (6,11).
Some very thorough and in-depth studies that correlated nutritional habits
and the development of ECC in children up to 3 years of age showed the smaller
prevalence of the condition in children that started taking salty food at the age of 7
months. Similar observations were noted among children consuming milk with no
sugar. (11,12). Furthermore, prolonged breast-feeding seems to represent an additional
important predisposing factor, which is often neglected (13). Many of the mothers
having children with this type of caries report a history of breast-feeding longer than
two years, often even three years, allowing the feeding in duration of several hours,
especially at night, which accelerates the implantation of Streptococcus mutans and the
development of caries. The carbohydrate lactose (C12H22O11), main nutritious
component during breast-feeding years, represents the most prominent predisposing
factor for ECC in such cases.
When analyzing the problem of ECC in children, it is important to note that
the education of the parents can be very important. Pregnant women can begin with
dispositional prophylaxis, by taking care of well-balanced nutrition rich in minerals,
which are necessary for endogenous mineralization of the teeth. It is also helpful to
both parents to learn more about cariogenic agents, how to fight them, to find out the
scientific facts on the formation of the plaque, predisposing sites, its visualisation
through the use of relevators, the choice of methods for the right implementation of
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oral hygiene, the importance of periodontal status and the possible consequences of
inadequate oral hygiene (12, 14-17).
The results of our study have shown that the prevalence of ECC in the this
sample amounts to 30%, which is the figure similar to those found in other studies
(22). The values of dmfs index were relatively high in both ECC cases and the control
group, which indicates that there is still a need for substantial improvement of
nutritional habits and oral hygiene in all pre-school children in Zagreb. The analysis of
our data showed that the share of the examinees with completely intact teeth amounted
to 38% in girls, and 27% in boys. The corresponding percentages from the world
literature range from 16% (Cape Town) to 83% (Oslo), which classifies our results
among the lowest third of countries with reported data (19). Still, an improvement was
observed in comparison to Zagreb data from 1987, when the share of caries free
children was only 12.5% (20).
Our study did not confirm the impact of baby-bottle feeding on the
development of ECC. That is in line with the recent findings from developing
countries, where ECC is also a considerable problem in children up to 4 years of age,
and where baby-bottle is very rarely used (5).
Our study confirmed the role of two very significant predisposing factors
for development of ECC: prolonged consumption of sweet beverages and late
introduction of teeth-brushing habbit. It appears that male gender is only an indirect
predisposing factor, since the corection for the first two factors did not confirm the
statistical significance that was found initially. Many studies point out that boys are less
likely to begin brushing the teeth early, and more likely to consume sweet beverages
during the night for a very prolonged period of time (18, 21-24). We may conclude
that this study revealed and confirmed the importance of early introduction of teeth-
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brushing and giving up the nightly consumption of sweet beverages in prevention of
ECC.
R E F E R E N C E S
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KNUTSON, Public Health Rep., 53 (1938) 751-765. - 5. MILNES, A., J. Public
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P. WEINSTEIN, J. Am. Dent. Assoc., 61 (1994) 293. - 8. WEINSTEIN, P., J. Public
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DOMOTO, E. JEFFCOTT, B. LEROUX, J. Dent. Child., 63 (1996) 113. - 11.
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P.R., K L. MCCLINTOCK, N. GREEN, J. LA FLEUR, Pediatr. Dent., 20 (1998)
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VAN PALENSTEIN, W. H. HELDERMAN, Community Dent. Oral Epidemiol., 22
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Child., 66 (1999) 85. - 19. SOLANKI, G. C., N. MYBURGH, M. H. MOOLA,
Community Dent. Oral Epidemiol., 19 (1991) 178. - 20. MILIČIĆ, A., V. GAŽI-
ČOKLICA, R. BRČIĆ, C. MIŠOLIĆ, Acta Stomatol. Croat., 27 (1993) 175. - 21.
LULIĆ-DUKIĆ, O., S. KIŠIĆ, Acta Stomatol. Croat., 30 (1996) 299. - 22. O
´SULIVAN, D. M., N. TINANOFF, Pediatr. Dent., 15 (1993) 41. - 23. GODSON, J.
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Author's address:
O. Lulić-Dukić
Department of pedodontics, School of Dental Medicine, University of Zagreb,
Gundulićeva 5, 10000 Zagreb, Croatia
ČIMBENICI KOJI PREDISPONIRAJU RAZVOJU KARIJESA BOČICE U
DJECE PRETŠKOLSKE DOBI U ZAGREBU
Cilj ove studije bio je istražiti čimbenike koji predisponiraju razvoju tzv.
karijesa bočice u djece pretškolske dobi u Zagrebu. Studija je provedena na uzorku
145 djece (77 dječaka i 68 djevojčica) u dobi između 2 i 5 godina, uključujući klinički
pregled dentalnog statusa i anketu o navikama djece provedenu među roditeljima.
Ukupna prevalencija karijesa bočice iznosila je 30%: u djevojčica 25%, a u dječaka
48%. Istraživanje rizičnih čimbenika provedeno je klasičnom retrospektivnom
studijom. Prosječna vrijednost Kp indeksa među zahvaćenim slučajevima iznosila je
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8.6, u usporedbi s 5.2 u kontrolnoj skupini (p<0.05). Hranjenje na bočicu nije
predstavljalo značajan rizik, ali su to bili noćna konzumacija slatkih pića nakon
navršena 24 mjeseca života, te izostanak usvajanja navike četkanja zubi nakon
navršena 24 mjeseca života (p<0.001). Studija je ukazala na važnost ranog
započinjanja četkanja zubi te što ranijeg odvikavanja od noćnog konzumiranja slatkih
napitaka u prevenciji karijesa bočice.
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Table 1:
Case-control analysis of potential risk factors predisposing to ECC in the sample of
145 examinees aged 2-5 years from the city of Zagreb, Croatia.
ECC Cases
(n=55)
Controls
(n=90) χ2 of F df p
Dmfs index
Mean value 8.6 5.2 1 < 0.05
Gender
Male 36 (65.5%) 41 (45.6%)
Female 19 (34.5%) 49 (54.4%) 5.43 1 0.020
Bottle-feeding at present:
Yes 5 (9.1%) 21 (23.3%)
No 50 (90.9%) 69 (76.7%) 4.71 1 0.043
Gave up bottle-feeding
during the: (n=48) (n=59)
First 24 months 22 (45.8%) 27 (45.8%)
25 months or more 26 (54.2%) 32 (54.2%) 0.00 0.994
Night consumption of
sweet beverages
Yes 8 (14.5%) 7 (7.8%)
No 47 (85.5%) 83 (92.2%) 1.69 1 0.194
Gave up night
consumption of sweet
beverages during the: (n=41) (n=46)
First 24 months 8 (19.5%) 26 (56.5%)
25 months or more 33 (80.5%) 20 (43.4%) 12.47 1 < 0.001
Regular teeth-brushing
started during the:
First 24 months 2 (3.6%) 41 (45.6%)
25 months or more 53 (96.4%) 49 (54.4%) 28.76 1 < 0.001
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