Early Childhood Caries: Prevalence, Risk Factors, and Prevention

eTiOLOgY OF eCC
Dental caries results from the interaction of various etiological 
factors, which might be concurrently present to initiate and pro-
gress the disease. The factors are (1) cariogenic microorganisms, 
(2) fermentable carbohydrates (substrate), and (3) susceptible 
tooth surface/host. There are a multitude of risk factors associ-
ated with ECC. Epidemiological studies have also documented 
low socioeconomic status, minority status, low birth weight, 
and transfer of microbes from mother to child. One to twelve 

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Anil and Anand
Early Childhood Caries
Frontiers in Pediatrics | www.frontiersin.org
July 2017 | Volume 5 | Article 157
percent of children younger than 6 years in the developed world 
experience ECC (
30
, 
31
). Child oral health-care behavior, feeding 
and cleaning behavior are associated with ECC among children; 
night time bottle feeding and frequent consumption of cariogenic 
food; late commencement of child tooth brushing and irregular 
brushing habits (
32
–
34
).
Cariogenic Microorganisms
Streptococcus mutans (SM) and Streptococcus sobrinus are the 
most common microorganisms associated with ECC. Lactobacilli 
also participate in the development of caries lesions and play an 
important role in lesion progression, but not its initiation (
35
). 
SM metabolizes sugars to produce acids, which contribute to the 
demineralization of tooth structure (
36
). These bacteria can be 
transmitted from mother to child (
37
). Preschool children with 
high levels of SM in the oral cavity had higher caries prevalence 
and a greater risk for development of new lesions (
38
). Milgrom 
et al. (
9
) found that children having a high SM levels were five 
times more prone to have dental caries. The major source of 
acquiring the SM is from the mother during first 12–24 months. 
Poor maternal oral hygiene maintenance and frequent snacking 
and sugar exposure increase the chances of transmission of the 
infection to child (
39
). SM isolates from infants indicated that 
the source of the SM in children is mainly from their mothers 
via vertical transmission through saliva (
40
, 
41
). Horizontal 
transmission of microbes may occur between siblings and care 
givers (
42
, 
43
). Infants delivered by cesarean section acquire SM 
earlier than vaginally delivered infants since these deliveries are 
more aseptic and the atypical microbial environment increases 
the chances of SM colonization (
44
). The Actinomyces species 
and specifically Actinomyces gerencseriae were also associated 
with caries initiation (
45
), while Bifidobacterium species was 
associated with deep caries lesions (
46
). Few non-mutans strep-
tococci that have acidogenic and aciduric properties were also 
associated with caries (
47
, 
48
). Epidemiological data suggest that 
Candida albicans also plays an active role in the pathogenesis of 
dental caries (
49
, 
50
). SM is the main bacteria that have strong 
association to dental caries whereas the other oral bacteria in the 
dental plaque could be involved in the initiation and progression 
of caries.
Diet
Dietary practices also play a significant role in the develop-
ment of ECC especially if it contains high levels of fermentable 
carbohydrates; the child is at higher risk for dental caries (
51
). 
Inappropriate feeding practice can prolong the exposure of teeth 
to fermentable carbohydrates which in turn may aggravate the 
chances of ECC. Bottle feeding during bedtime or sleeping has 
been associated with the initiation and development of caries in 
children (
52
). SM converts fermentable carbohydrates into acids, 
which can demineralize enamel and dentin (
53
). Studies have 
shown that cow milk has minimal cariogenicity due to its mineral 
content and low lactose level (
54
–
56
). Iida et al. (
57
) showed that 
breast feeding and its duration were independently associated 
with an increased risk for ECC among 2- to 5-year-old children. 
A systematic review revealed that breast feeding for more than a 
year and at night might be associated with an increased prevalence 
of dental caries (
58
). Infant feeding practices such as frequent 
exposure to sugar, frequent snacking, taking sweetened drinks to 
bed, sharing foods with adults, as well as maternal caries status, 
oral hygiene and dietary habits predispose to early SM coloniza-
tion and establishment of high MS counts (
51
).