The purpose of this study was to determine the fluoride uptake in enamel of young permanent teeth between Glass Ionomer Cement and Compomer filling. The subject for this study was 21 premolar, and each tooth divided into 2 parts. The first part filled with Glass Ionomer Cement (Fuji IX ART,GC), and the second part filled with Compomer (Dyract, Denstsply), so the samples were 21 Energy Dispersive X-Ray Spectrophotometry analysis of Glass Ionomer Cement and 21 Energy Dispersive XRay Spectrophotometry analysis of Compomer. Using t-test the fluoride uptake in the enamel of young permanent teeth with Glass Ionomer Cement and Compomer filling was significantly increased(t=3,705 p=0.001). The increasing of fluoride uptake in
the enamel of young permanent teeth with Glass Ionomer Cement filling is more high than Compomer. This study also showed fluoride uptake from Glass Ionomer Cement and Compomer which exhibited in enamel of young permanent teeth was significantly different (t=3,705 p=0.001). Fluoride uptake of Glass Ionomer Cement filling in enamel of immature teeth was much more compare to Compomer.