The aim of fissure sealing is to protect the surface of the tooth by a protective layer, thus preventing the development and/or transmission of caries. The surface of the molars is rough, fissured. Food debris can stuck in these fissures and the quickly developing bacterias start decaying the tooth. Through fissure sealing we brush the surface of the tooth with this thin liquid material that flows into the fissures then hardens. For children it can be applied on both the milk and final molar teeth. All the final molar teeth should be protected for the children who are tainted to caries. If the surface of a children’s molar teeth is dark brown, black or other than the colour of the teeth, but still unhurt, this treatment might be considered as it is quickly done, absolutely painless, drilling-free, absolutely tooth-friendly and much cheaper than the filling. The process of fissure sealing: we dry the tooth by blowing air on it and then brush it with a coloured liquid. After a short time we wipe it, rinse it with water and dry it again. Then we apply the liquid fissure sealing material that flows even into the smallest fissures. After this – if the substance bounds to light – we illuminate it for 20 seconds. It hardens then we wait for 1-2 minutes while it fully bounds. The coloured fluid is acid that makes the surface of the tooth more rough, so the fissure sealant can grip onto it. The sealant protects the tooth surface effectively for 2-3 years from getting decayed and emits fluoride constantly that strenghtens the tooth. A slightly modified method can be applied on the intact molars of adults. One of the best advantage of fissure sealants is that they emit fluoride. Bacterias cannot develop in an environment with certain concentration of fluoride – thus not on the sealant or around it.