Abstract
The objective of this study was to investigate the relationship amongst early childhood caries (ECC), economic development, and dental public health programmes in Hong Kong. We searched exhaustively qualitative and quantitative data on the oral health policy, dental service, public health strategies of caries control and epidemiologic surveys on ECC. We then performed meta-regression to explore the impact of the Human Development Index (HDI), gross domestic product (GDP) growth, water fluoridation, oral health promotion, dental school establishment, free education, and dental workforce on ECC prevalence in 5-year-olds. We found that the first government oral health survey was conducted in 1960, when Hong Kong experienced significant growth, as the HDI indicated. The survey revealed that 97% of 6- to 8-year-old children experienced ECC. Water fluoridation was implemented in 1961 at 0.7 ppm (0.9 ppm in winter) to prevent caries. The government offered free 9-year education in 1978. In 1981, the government established a dental school to improve a low dentist-to-population ratio of 1:9000. The ECC prevalence amongst 5- to 6- year-old children was reduced from 84% in 1968 to 63% in 1986. The Department of Health created an oral health education division in 1989. The ECC prevalence for 5-year-old children was further reduced to 44% in 1997. The ECC prevalence amongst 5-year-old children was stabilised at 51% both in 2001 and 2011. However in 2021, the prevalence of untreated ECC increased to 57% during the outbreak of COVID-19. Meta-regression analysis showed that ECC prevalence was not linked to GDP growth but decreased with improvements in HDI, the provision of 9-year free education, the establishment of a dental school, fluoridation of water supply, and implementation of territory-wide oral health promotion. In conclusion, better education, living conditions, and dental public health programmes have improved children's oral health in Hong Kong.