A sealant is a thin, plastic coating applied to the chewing surface of molars, premolars and any teeth with deep grooves. Very often dental decay begins in these deep grooves. Teeth with deep grooves are hard to clean and are very susceptible to decay.
A sealant protects the tooth by sealing deep grooves, creating a smooth, easy to clean surface. Sealants can protect teeth from decay for many years, but need to be checked for wear and chipping at regular dental visits.