Early childhood caries among 3- to 5-year-old children in Hong Kong

Abstract

The aim of this study was to describe the prevalence of dental caries among 3- to 5-year-old children in Hong Kong and to investigate the factors associated with their dental caries status. Seven kindergartens in Hong Kong were selected using stratified random sampling. The 3- to 5-year-old kindergarten children were invited to join the study. The participants' parents were asked to complete a questionnaire regarding their children's demographic and socio-economic backgrounds, their dental habits and their own dental knowledge. Dental caries experience was measured using the decayed, missing and filled primary teeth (dmft) index. The visible plaque index was adopted for recording oral hygiene. The relationships between caries experience and children's demographic backgrounds, dental habits, oral hygiene and parental dental knowledge were studied using a zero-inflated negative binomial (ZINB) regression analysis. Among the 1,204 participating preschool children, the overall prevalence of dental caries (dmft > 0) was 46%. The mean dmft score was 2.1 ± 3.4. The prevalences of dental caries among the 3-, 4- and 5-year-old children were 38%, 43% and 55%, respectively. ZINB regression analysis revealed that the study children who were boys, came from families with lower incomes, had dental visit experiences, had higher plaque scores and had parents with lower levels of dental knowledge, had higher dmft scores (P < 0.05). Dental caries is prevalent among preschool children in Hong Kong. The caries experiences of the study children are associated with gender, family income, parental dental knowledge, dental visit experience and oral hygiene.