Hemdan M.E ^*, El-kalla I.H ^**, Abdellatif A.M ^***, Whba A.H^****. * Bachelor of Dentistry 2009, Mansoura University, Egypt ** and ***: Professors of Pediatric Dentistry, Mansoura University, Egypt ****: Lecturer of Pediatric Dentistry, Mansoura University, Egypt Abstract: Objectives: This study aims to assess the ability of fluorescent camera to detect occlusal caries and caries under clear or opaque fissure sealant; either present before sealant application or recurrent after placement of fissure sealant. Methods: thirty molars with simple occlusal caries were divided into two groups one was sealed with clear sealant and the other with opaque one. Each tooth was imaged by Soprolife Fluorescent camera pre and post sealant application. The P value was calculated for the difference of the lesion (Mesio-distal width ratio) in pre and post images. Thirty sound premolars were equally divided and imaged after sealing of them prior to and after immersion in demineralizing gel. The P value was calculated for the sealant loss after demineralization. Results: a) Molar groups: The clear sealant molar group showed a non-significant P value (0.16) after comparison between pre and post clear sealant application fluorescent images, however the opaque sealant molar showed complete lesion masking in post opaque sealant fluorescent images. b) Premolar groups: The opaque sealant premolar group showed a non-significant P value (0.08) after  comparison between pre and post immersion of sealed-premolars in demineralizing gel, however the clear premolar one showed a significant P value (0.008*). Conclusion:Soprolife is an efficient tool in detection and monitoring of an occlusal lesion under the clear sealant only. On the other side the opaque sealant has high acid resistance than the clear one.