 Background: Occlusal caries is the main reason for restorative therapy in the young permanent dentition, but restorations have limited survival time and may also weaken the tooth. An intact fissure sealing is an effective preventive treatment of occlusal caries lesions and may be used therapeutically to arrest the caries progression. However, the major challenge with fissure sealants is the frequent need for re-treatments, mostly due to inadequate retention. 