Sealants are a dental treatment consisting of applying a plastic material to one or more teeth, for the purpose of preventing dental carries ( cavities) or other forms of tooth decay.
Because the teeth in the back of the mouth (molars and premolars) have numerous pits and fissures on their biting surfaces, certain areas of these teeth are often difficult to clean even with vigorous tooth brushing. To remedy this, research into dental sealants began in the 1960's, and by the 1970's the first generation of sealants became available and were approved by the FDA.
Sealants painted over pits and fissures on the chewing surfaces of back teeth block food from being trapped and any carbohydrates like sugar being changed to acid by resident plaque bacteria and halts demineralization and the carries process.
Dr. James L. Johnson