Objectives: This in vitro study was carried out to evaluate the remineralization efficiency of nanohydroxyapatite (Nano-HAp), nano-bioactive glass (Nano-BAG), and sodium fluoride (NaF) on initial enamel caries of primary molar teeth. Material and Methods:The extracted primary molar teeth's enamel was used to create a total of 108 enamel samples.A particularly prepared demineralized solution was us...