Caries-risk factors among 3-year-old Hong Kong children: a cross-sectional study

Abstract

Objectives: Early childhood caries (ECC) is a major public health problem among preschool children in Hong Kong. Aim of this study was to find out the major risk factors of ECC among 3-year-old children. Methods: All 3-year-old children from 29 selected kindergartens in Hong Kong where the water is optimally fluoridated at 0.5 ppm were invited to join in this study. A parental consent form and a questionnaire regarding the children’s oral health habits and social-economic background were distributed to their parents through the kindergarten. Parents who agreed to let their children participate in the study completed the questionnaire. Children with parental consent were examined by a trained dentist in their kindergarten using disposable mouth mirrors and an intra-oral LED light. Caries status was recorded using the dmfs (decayed, missing, or filled surface) index according to diagnostic criteria recommended by the WHO. Chi-square test and logistic regression analysis was performed to identify risk factors of ECC. Results: All 29 invited kindergartens participated in this survey. Parental questionnaire were distributed to 6,331 kindergarten children. A total of 5,351 children agreed to join this study, and 5,167 children (82%) were clinically examined. Among them, 1,130 children (22%) had dental caries experience (dmfs>0). Logistic regression analysis found age of stopping bottle-feeding, age of starting tooth-brushing, snack intake frequency, dental visit experience, place of birth, monthly family income, main caretaker, and mother’s education level were factors associated with ECC of the children. Conclusions: ECC of Hong Kong young preschool children is associated with some oral health-related habits, and their demographic and family backgrounds.