Project Summary/Abstract: Adolescent dental decay and its complications diminish quality of life and can lead to lost school days, emergency room visits, and in extreme cases even death. Dental sealants are an effective intervention to reduce dental decay, but sealant prevalence among adolescents remains low and has disparities by sociodemographic characteristics. While 2nd molars are seldom erupted enough to receive sealant application prior to middle school, the majority of school-based sealant programs (SBSP) — an efficient public health initiative typically aimed at low-income schools — serve elementary schools only, and thus predominantly limit their reach to 1st molars. This lack of adoption of SBSPs for 2nd molars represents a critical gap in implementation of an effective oral health intervention for adolescents that is also well documented to reduce disparities. The objective of this research is to investigate the effect of 2nd molar sealants on dental caries, the reach of middle school sealant programs in the US, and the impact of increasing access to 2nd molar sealants through SBSPs on oral health and related disparities among adolescents. The first aim is to determine the prevalence of 2nd molar sealants and the resulting impact on dental caries in adolescents among various racial/ethnic and income groups. Multivariable regression models will be used to examine the probabilities of receiving 2nd molar sealants and of experiencing dental caries in the presence/absence of sealants. The second aim is to gather data on middle school sealant programs in the US by surveying state oral health program directors, SBSP coordinators, and providers. This data will be analyzed to understand availability and reach of SBSPs to adolescents including number of middle school programs, their size, program characteristics, funding mechanisms, costs and student participation rates. The third aim is to estimate the impact of increasing availability of SBSPs to adolescents using estimates and data from Aim 1, Aim 2, and the literature. A simulation model will be built to model various SBSP characteristics and to measure resulting impact in number of sealants, averted decay, and cost-savings of averted restoration by race/ethnicity and income level. This research will fill a critical gap in information on SBSPs and provide clearer understanding of the sealant and related dental caries experience for 2nd molars by race/ethnicity and income level. The findings will furnish comprehensive information about the status of middle school sealant programs in the country. It will produce reliable estimates of the potential impact of increasing the reach of SBSPs to more adolescents and its contribution to reducing disparities. This R21 will lead to a subsequent R01 project to support increased implementation of SBSPs for adolescents, identify ways to improve the efficiency of these programs and reduce oral health disparities.