Background: The authors conducted a two-year longitudinal study to show the predictive abilities of a caries activity test (Cariostat, Dentsply-Sankin, Tokyo), and to include the predicted screening indexes that were based on previous caries activity test results and lifestyle factors that influence caries activity.
Methods: The subjects were 1,206 children born in 2000. These children participated in health examinations at 18 months, 2 years and 3 1/2 years of age at Kurashiki-City Public Health Center in Kurashiki-City, Japan. Two of the authors performed caries activity tests at 18-month and 2-year examinations. Questionnaires regarding the patient's lifestyle were mailed to each participant's parents or guardians. The authors analyzed these questionnaires to evaluate lifestyle factors that made participants susceptible to caries.
Results: A caries activity test score at 18 months of age not only reflected caries incidence but also predicted caries incidence and screening results in 2- and 3 1/2-year-old children. A caries activity test score at 2 years of age both reflected and predicted children's caries incidence and screening results at 3 1/2 years of age. Breast-feeding and use of the bottle to intake liquids other than water produced significant caries susceptibility in 18-month-old children. Additionally, increased frequency and total time of sucrose intake put 2-year-old children at high risk of developing caries and failure of parental brushing produced a high risk in 3 1/2-year-old children.
Conclusions: A caries activity test could predict 3 1/2-year-old children's caries risk based on 18-month and 2-year-old test results. Early weaning, less sucrose intake and toothbrushing by parents were effective in reducing a child's caries risk.
Clinical implications: The caries activity test is more useful than oral examination because it can indicate the need for caries-preventive treatment before a carious lesion actually is manifest.