These are thin plastic coatings that are applied to the chewing surfaces of back teeth to prevent tooth decay. The pits and grooves that naturally take place on the chewing surfaces of teeth can often get affected by plaque, because these are highly vulnerable to cavities amongst children and teens. Topical fluorides do not provide much benefit in this case. But, Sealants and fluoride together are quite effective in preventing tooth decay. Usually, sealants last for 5 -10 years if properly taken care. During your each dental check-up, the dentist will examine whether the sealants are unharmed. To enhance the life of sealants we advise you to avoid crunchy and hard foods.