Prevalence of early childhood caries and associated factors among children 3–5 years in selected government-aided primary schools in Kampala, Uganda: a cross-sectional study

Early Childhood Caries (ECC), defined as the presence of one or more decayed, missing, or filled primary teeth in children under six years, is a major global public health concern with a prevalence of 43–48%. Its occurrence is influenced by poor dietary and oral hygiene practices, socioeconomic status, inappropriate nutrition, limited access to dental care, and low parental awareness. There is need for updated data on ECC in urbanizing areas like Kampala where there are shifts in food systems including increased availability of processed sugary foods which heighten the ECC risk. This study therefore aimed to determine the prevalence of ECC and associated factors among children aged 3–5 years of attending selected government-aided schools in Kawempe division, Kampala district. This cross-sectional study, conducted between March and April 2025, involved 417 children aged 3–5 years from five selected government-aided schools in Kawempe division. The schools were chosen through cluster sampling and pupils through consecutive sampling. Data on ECC, sociodemographic, oral hygiene, and dietary factors were collected using a modified World Health Organization (WHO) oral health assessment form and a structured questionnaire. Analysis in STATA version 18 employed survey analysis methods to estimate prevalence and modified Poisson regression with clustered-robust standard errors to identify ECC predictors. Of the 417 participants enrolled, 226 (54.2%) were male. The median age was 5 (Interquartile range (IQR):4–5) years. The prevalence of ECC was 48.7% (95% Confidence Interval (CI): 38.4–59.1). The factors associated with ECC were age of initiating brushing (adjusted prevalence ratio (aPR): 1.69, 95%CI: 1.44–1.98, P < 0.001), sugar intake (aPR: 1.07, 95%CI: 1.01–1.13, P = 0.023) and absence of assisted brushing (aPR: 1.46, 95%CI: 1.21 − 1.77, P < 0.001). Age was adjusted for as a potential confounder form literature. The prevalence of ECC was high in this study, affecting nearly 50% of the participants. The age of initiating tooth-brushing, assisted tooth-brushing and intake of sugary foods were significantly associated with ECC in this study. These findings can serve to inform national oral health policies to strengthen oral health education and caries prevention efforts.