A pit and fissure sealant is a thin white coating that is put on the chewing surface of back teeth. Our molars and premolars have lots of pits and fissure where food tends to get stuck and is not easily removed from there. A sealant flows into these grooves and creates a smooth surface where the food slides off it and is easier to clean. This is a preventive measure taken for children and adolescents to prevent decay of teeth. However regular brushing and flossing should be continued as directed by the dentist even after this procedure is carried out.