A dental sealant is a special plastic coating that is applied to the tooth to protect it from decay. When teeth are treated with sealants, they are less likely to get cavities. Sealants can be applied quickly and painlessly. These are the reasons why so many dentists recommend sealants for patients.

What causes tooth decay?

Teeth are covered with a sticky film of bacteria called plaque (rhymes with "back"). The bacteria change sugar into harmful acids that attack the hard layer on teeth called enamel. Over time, these attacks may break down the enamel and cause tooth decay, or cavities.

Tooth decay often occurs on the chewing surfaces of the back teeth. These surfaces have pits and grooves that trap plaque and bits of food. The pits and grooves are hard to keep clean, because toothbrush bristles cannot reach into them. That is how decay starts in the pits and grooves and a cavity forms.

Molar magnified
Even a toothbrush bristle is too big
to reach inside a groove in the tooth

How do sealants work?

A dental sealant is a plastic material (resin) applied to the chewing surfaces of the back teeth. The resin flows into the pits and grooves in the teeth. The sealant forms a barrier, protecting enamel by sealing out food and plaque.

How are sealants applied?

It takes only a few minutes to seal each tooth. The chewing surfaces are cleaned to make it easier for the sealant stick to the tooth. Then the sealant is applied to the chewing surface, where it sticks or bonds to the tooth and hardens. A special light may be used to help the sealant harden.

Tooth surface before a sealant
is applied.
Tooth surface protected by a sealant.

How long do sealants last?

Sealants may last several years before they need to be replaced. Over time, sealants can become loose or worn. Then they will not protect the teeth as well. During regular dental visits, your dentist will check the sealants and reapply them if needed.

How else can I protect teeth from decay?

ADA SealSealants protect only the chewing surfaces of teeth. Decay can still form between the teeth. To prevent decay, take good care of the teeth at home. It is also important to have regular exams and cleanings at the dentist's office.

To help keep your mouth healthy, be sure to floss or use another between-the-teeth cleaner once a day and brush twice a day. Ask your dentist about using fluoride mouthrinse to prevent cavities. Look for products that display the ADA Seal of Acceptance, which tells you that the product meets ADA standards for safety and effectiveness.

Who should get sealants?

Though sealants are most often placed in children and teenagers, adults can sometimes benefit from sealants too.

A sealant can be placed on a tooth that does not have a cavity in its pits and grooves. Sometimes a sealant can also be placed on a tooth that has decay at an early stage, before a cavity has formed.

Prevention is always better than treatment. Sealants are very useful in stopping tooth decay on the back teeth and can save patients money over time. Your dentist can make sealants part of your plan for a healthy mouth.

Sealant photos courtesy of Dr. Adam A. Francois

American Dental Association
Patient education content ©2014 American Dental Association. All rights reserved. “ADA” and the “ADA” Logo are registered trademarks of the American Dental Association. Sealant photos courtesy of Dr. Adam A. Francois.