Owing to its globally high prevalence, dental caries is a 'pandemic' disease characterized by a high percentage of untreated carious cavities causing pain, discomfort and functional limitations. Untreated carious cavities, furthermore, has significant impact on the general health of children and on social and economic wellbeing of communities. The focus on caries has recently shifted to the development of methodologies for the detection of the early stages of caries lesions and the use of non-invasive treatment for these lesions. So, diagnosis of dental caries at early stage is very important The focus on caries has recently shifted to the development of methodologies for the detection of the early stages of caries lesions and the use of non-invasive treatment for these lesions. The non-invasive treatment of early carious lesions by remineralization has the potential to be a major advance in the clinical management of the disease.