Fissure sealants act as a barrier that protects tooth surfaces that are vulnerable to bacteria. Sealants are usually placed on the chewing surfaces of the back teeth – premolars and molars.
The first permanent molars come through behind the last baby tooth at around six years of age. When they erupt, their surface has not yet reached its final mineralisation. The lower mineral content makes them very vulnerable to the bacteria and acids in plaque. In childhood, hygiene habits are usually not yet well established, which adds to the risk. These teeth do not replace any baby teeth, and parents often notice them in their child's mouth only later. The area most at risk of decay is the groove on the chewing surface, where mineralisation is completed last. These teeth reach their final degree of mineralisation and strength up to two years after they come through. Sealants stop bacteria from getting into and staying on the tooth surface.
Sealants are preventive coatings placed in a minimal amount, without removing any of the tooth surface beforehand. They have low wear resistance, so they are not placed in areas of strong contact between the teeth. A check-up is needed every six months, because sealants wear away and are repaired if necessary.
Placing a sealant is a short procedure that starts with preparing the tooth. The surface is cleaned with a brush and rinsed to remove food remains. The tooth is coated with a material that bonds it to the sealant, and then the sealant itself is applied. To seal the surface completely, it is very important to keep the tooth isolated from saliva while the sealant is placed. This is often the most difficult part and can make the procedure take longer. If your child cooperates and does not get tired, sealants can be placed on several teeth in one visit.
As long as the sealant covers the tooth, the surface is protected from decay. If there are signs of early decay, a sealant should not be placed (it is contraindicated), because it will not stop decay that has already started. Chipped parts of the coating become retention areas – places that trap more plaque and create a risk of decay. That is why checking sealants every six months is essential, and any defect is corrected. If the tooth was not kept dry when the sealant was placed, the bond is weakened and the sealant may come off. That is why sealants are often made in a colour different from the teeth – so that their condition can be monitored.
Placing sealants on teeth that have finished mineralising is not essential, but it can be done to reduce food trapping and therefore the risk of decay. For this reason, sealants can also be placed in adult patients.
Preventive coatings reduce the risk of decay on the tooth surface they cover. Plaque, as the main cause of decay, must be removed by brushing twice a day and using dental floss or interdental brushes.
This article is for information only and does not replace an examination by a dentist.
