A sealant is a white “plastic” coating that fills in the grooves and pits on the chewing surfaces of the back teeth to help protect from cavities in the spots most likely to cause cavities for children. The deep grooves and pits can normally collect food and bacteria from plaque that is difficult to clear away with brushing alone, putting those teeth at risk for decay. Sealants “seal out” the debris from the areas to prevent decay.
Sealants are typically placed on permanent (adult) molars and premolars. Research shows placement of sealants does greatly reduce the risk of cavities for children, even if they do not last forever. Sealants can last for many years though if cared for properly and do provide better protection when they are still intact. Sealants can last longer with good oral hygiene, avoiding eating very tacky foods and candies which can pull them off, and avoiding chewing on hard candies or ice which can crack them.