The pits and grooves of your teeth are prime areas for opportunistic bacteria and resulting decay. Regular brushing sometimes misses these intricate structures on the biting surfaces of your teeth. A sealant is a liquid substance that hardens after application on these surfaces and has been shown to play an important role in the prevention of tooth decay. These sealants prevent the intrusion of bacteria and other debris from entering the pits and grooves of your teeth. The likelihood of developing decay begins early in life, so children are obvious candidates. But adults can benefit from sealants as well.