What proportion of caries into dentine at age 5 is present at age 3?

Objective: To explore the proportion of decay at age 5 in Wales presenting by and after age 3 years from geographical and deprivation perspectives. Basic research design: Retrospective analysis of data from independent cross-sectional studies of 3-year-olds in early 2013 and 5-year-olds in school year 2014/5. This includes novel graphical presentation of caries at age 3 and estimated 3-5 caries increment at age 5. Setting and participants: NHS oral health surveillance programme in Wales examining children in nurseries at age 3 and in schools two years later. Main outcome measures: %d₃mft⟩0 at ages 3 and 5 years, plus estimated 3-5 caries increments for these two indices. Data are analysed using index of deprivation and Health Board population density (as a proxy for rurality). Results: In most Health Boards and all deprivation quintiles there is a larger proportion of caries into dentine presenting between ages 3-5 than by age 3. In rural Health Boards the proportion of caries present by age 3 is much smaller. In one Health Board more caries presents by age 3 than after. In rural Health Boards the current prevention activity has potential to push reported caries prevalence at age 5 below 10%. In urban Health Boards action by age 5 will be required to push caries prevalence significantly below 20%. Conclusions: Findings from this analysis suggest need for earlier prevention activity in some Health Boards in Wales.