Capturing geographical inequalities in children's experience of dental health support using synthetic estimation technique and understanding their relationship with geographical inequalities in child dental health in England.

This study aimed to estimate the proportion of families with five-to-fifteen-year-olds experiencing inadequate dental health support as a consequence of their parents' socioeconomic conditions and deprivation in their neighbourhood across small geographies in England using synthetic estimation technique and explore its association with area-level proportion of children experiencing dental caries. Secondary analyses were performed using Children's Dental Health Survey (CDHS) 2013, National Dental Epidemiological Programme (NDEP) 2018-2019, and Census 2011. Multilevel logistic regression using CDHS (five-to-fifteen-year-olds; n = 2177) derived odds of a child experiencing inadequate dental health support (child's poor dental attendance, parents not accompanying a child to dental visits, not using sugar-free/dental chewing gum) based on parents' family status, employment, and neighbourhood deprivation. These odds and census-informed population counts were used to derive the indicator of 'estimated percentage of families with children experiencing inadequate dental health support in a census-based geography of ∼7500 people (n = 6791)'. Unadjusted linear regression was undertaken to examine the relationship between the indicator and NDEP-based percentage of five-year-olds experiencing dental caries in larger geographies (n = 397). Results indicated that inadequate child dental health support [CDHS mean = 8% (SD:0.27%)] was significantly associated with higher neighbourhood deprivation and an interaction effect from being both a lone and an unemployed parent. Increased area-level percentage of families with children experiencing inadequate dental health support (range:3.7%-15.2%) was associated with 1.59 (95%CI:1.14-2.04) rise in area-level percentage of five-year-olds experiencing dental caries. This study underscores the need for targeted support for lone and unemployed parents and families living in the most deprived areas to promote children's dental health.