Extensive advances have been made in understanding the relationship between the oral environment and the bacterial disease of caries.The initiation of the disease and the progress of the hidden lesion will be surreptitious, relatively slow, and difficult to define until there is surface cavitation. If hidden disease is recognized in the very beginning, it can be cured in initial stage. Dental radio graphs have an important role in caries detection. The DIAGNOdent and DIFOTI devices can be useful in the detection of incipient and hidden carious lesion.The goal of minimally invasive operative dentistry is to achieve maximum conservation of sound tooth structure to maintain a healthy dentition over a lifetime. Now, greater emphasis must be placed on assessing caries- risk, shifting patient to a low caries risk status, remineralizing non cavitated lesions by using remineralizing pastes, abandoning the surgical approach to caries management and repairing rather than replacing defective restorations.