Sealants are made of a similar material to tooth-colored fillings. They are placed in the deep grooves and pits of the back teeth to seal off areas, so food is not trapped. Sealants essentially take a groove that is V-shaped and makes it more U-shaped. This allows the saliva to flow the food debris out of the groove, instead of it sticking there until the teeth are brushed well.
No anesthetic “numbing” is needed to place sealants, as they do not hurt to apply. To prepare the teeth, the top grooved area is thoroughly cleaned. Then cotton may be placed on either side of the tooth. The tooth must be dry for the sealant to bond to the enamel. Then the sealant is flowed into the grooves and a blue light is shined on the tooth for 30 seconds. The light hardens the sealant and bonds it to the enamel. The bite will then be checked. If there are any places where the sealant is a little too thick, the dentist will smooth the spot down until it is comfortable.
Sealants typically last 5 to 10 years with proper care, but can last much longer.
No, sealants are not harmful, since they are not absorbed or eaten – just a layer added to the tooth.