This paper aims at illustrating the different diagnostic methods and compare the reliability of the Digital Imaging Fiber Optic Transillumination (DIAGNOcamTM, KaVo Kerr, Brea, California, US) with the use of intraoral radiographs. Since the discovery of radiography, various methods have been introduced in order to provide early diagnosis of caries. In this review, specific keywords have been chosen on different search engines and medical databases. Scientific pa-pers published from 1990 to 2022 were included. Nine articles comparing two different methods for early detection of carious lesions were selected. An analysis of the existing literature seems to support the hypothesis that making diagnosis by using the Digital Imaging Fiber Optic Transillumination systems represents a safe and effective support for early diagnosis of interproximal carious lesions within enamel. However, it is still to be considered a complementary method to traditional bitewing and periapical radiographs.