OBJECTIVETo evaluate the significance of variables such as saliva mutans streptococci, oral hygiene, dietary habits, oral hygiene habits and socio-economic status in assessing the level of caries risk for preschool children.

METHODSThe case-control study was used. Among 1018 children at the age of 4 and 5, 204 children with dmft > or = 6 were included in caries group and 237 children in caries free group. Saliva mutans streptococci, saliva flow rate and buffer capacity, and debris index were tested for all children. Their mothers finished the standardized questionnaire for information about dietary and oral hygiene habits of the children, breast and bottle feeding history and socio-economic status.

RESULTSLogistic regression analysis showed that the saliva mutans streptococci (OR = 3.019), debris index (OR = 2.263), frequency of consumption of snacks and sweets (OR = 1.729), frequency of intake of soft drinks (OR = 1.496) and use of sweetened food in nursing bottle (OR = 2.255) were significant factors.

CONCLUSIONSHigh level of saliva mutans streptococci, bad oral hygiene, frequent intake of sweet food, and sugar contents in nursing bottle were the important risk factors for dental caries on primary teeth.