Sealants are generally used to help prevent tooth decay on the biting surfaces of back teeth (molars). The natural grooves of these teeth can trap food that can resist casual brushing and rinsing. If left in place, the trapped food allows bacteria to multiply, eventually causing tooth decay and requiring costly attention.
Sealants are painted directly onto the tooth where they seal the natural grooves to help prevent tooth decay. While sealants are durable, they are not permanent. They can last up to 5 years of normal wear before needing replacement.
Sealants offer a cost-effective, preventative step to reduce the chances of tooth decay on the chewing surfaces of molars. However, they do not replace the need for regular brushing and flossing. If there is decay on the tooth chewing surface, then the decay would be removed and a composite filling would be placed.