Whv. Helderman et al., CARIOGENICITY DEPENDS MORE ON DIET THAN THE PREVAILING MUTANS STREPTOCOCCAL SPECIES, Journal of dental research, 75(1), 1996, pp. 535-545
This review aims to compare the occurrence and distribution of mutans
streptococci in Africa, Europe, and North America and in addition will
try to offer explanations for existing relationships among salivary m
utans streptococci counts, dietary patterns, and dental caries. The li
terature reveals that salivary mutans streptococci counts in child pop
ulations of the three continents are comparable. The distribution of m
utans streptococci species, with a predominance of S. mutans followed
by S. sobrinus, and the virtual absence of other mutans streptococci s
pecies are also comparable. Although it is widely believed that diet h
as an important effect on mutans streptococci counts, this review prov
ides evidence that this does not hold true when variations in dietary
patterns are moderate, as they normally are in real-life situations. S
ince the diets of the child populations in the three continents vary m
oderately, a strong dietary-induced effect on salivary mutans streptoc
occi counts cannot be expected. The observed analogous salivary mutans
streptococci counts in these child populations are thus 'not surprisi
ng' but are in accordance with the conceptual expectation. The differe
nces in caries experience in children of the three continents cannot b
e explained by the prevailing mutans streptococci species but instead
should be attributed to differences in the cariogenicity of the variou
s diets. The fact that the cariogenicity of the diet determines the de
velopment of dental caries while hardly affecting the mutans streptoco
cci counts explains the limited value of the latter as an indicator of
dental caries. The reviewed literature shows that mutans streptococci
are ubiquitous in children aged 7 years and older in Africa, Europe,
and North America. Mutans streptococci should therefore be considered
as belonging to the indigenous microflora of the human mouth.