Remineralization is increasingly accepted as a viable non-invasive approach for restoring carious teeth, at least during the earlier stages of the caries process. According to the principles of minimal intervention dentistry, optimal non-invasive strategies are preferred for treatment of early enamel lesions. This study was designed to investigate the remineralising efficacy of casein phosphopeptide amorphous calcium phosphate on early enamel lesions using energy dispersive x-ray analysis for quantitative assessment and scanning electron microscope for morphological changes. It can be inferred from the study that casein phosphopeptide amorphous calcium phosphate paste significantly remineralises the early enamel lesions substantially .This could be attributed to the diffusion of calcium and phosphate minerals into the surface with the aid of saliva as the transport medium. This book gives an overview of how we can measure the amount of mineral loss or gain quantitatively along with the morphological changes.