Preschool and Later Caries in Deciduous Teeth: Different Risk Indicators?

Objectives: To compare the risk indicators for deciduous caries in the preschool years with those for caries developed after beginning school.

Methods: Data were collected in the South Australian component of the Child Oral Health Study; a prospective longitudinal study of 5-17-year-old children in various states in Australia. Socio-demographic, behavioural, fluoride exposure and dietary data were collected by a parent-completed questionnaire. Clinical data were collected by school dental therapists at routine examinations with up to 3 years follow-up. Risk indicators for preschool caries examined associations with prevalence of caries present in 5-6-year-old children at baseline and compared with the risk indicators for the development of new caries in the follow-up period for the same sampled children. Multivariate statistical models predicted odds of caries experience using information about exposure to water fluoridation, fluoride toothpaste use, tooth-brushing, household income and sugar consumption.

Results: Response rate for South Australia was 69%, yielding 644 5-6-year-olds with at least one follow-up visit. Prevalence of caries in 5-6-year-old children was 49.4% and 39.4% subsequently developed caries; of those 70 were new cases. In multivariate analysis, risk indicators for baseline caries included lifetime exposure to water fluoridation (0% vs 50%: OR 2.02, 95% CI 1.20 -3.42), and number of intakes of sugar per day (OR 1.15, 95% CI 1.08-1.23) adjusting for tooth-brushing, toothpaste use, income and sex. Risk indicators for new caries in the follow-up period were the same without controlling for baseline caries. When caries at baseline was added to the model, baseline caries became significant (OR 1.10, 95% CI 1.06-1.15) and number of intakes of sugar (OR 1.14, 95% CI 1.07-1.22) remained.

Conclusions: The risk indicators for preschool caries and subsequent caries suggest that limiting sugar intake and promoting water fluoridation should be the priorities for health promotion among young children.