The top surfaces of your teeth (the biting surface), are not smooth and flat. They are cris-crossed with tiny hills and valleys, called fissures. These are places where plaque can build up safe from your toothbrush and dental floss. Some of the pits and fissures are so narrow that even a single bristle from your toothbrush is unable to get deep enough to clean them out.
One method of preventing cavities from developing in the fissures is to seal them off with a special varnish called a fissure sealant.
The dentist will clean the tooth first, then apply a solution to ‘etch’ the surface and make it easier for the fissure sealant to stick. Keeping the area dry and away from your saliva during the application is very important. If the tooth gets wet, the sealant might not stick properly. Once everything is ready, your dentist applies the sealant over the fissures on the tooth surface. A special kind of light cures the sealant and makes it ready for use.