Dental Health: Do Dental Sealants Prevent Tooth Decay?
What are Dental Sealants?
Dental sealants, also called fissure sealants, are thin plastic coatings that are applied into the grooves of the molar teeth to seal them from bacteria. It may also be applied to premolar
teeth if the grooves in these teeth are deep or if the individual has a high risk category for developing tooth decay. Fissure sealants are usually indicated in children's molar teeth as soon as possible
after they erupt into the mouth. This is because the pit and fissures of these teeth are most susceptible to tooth decay upon eruption into the mouth. Over time, after a length of exposure in the mouth, it is believed that the pit and fissures decrease in susceptibility to tooth decay and no longer warrant the use of fissure sealants.
Resin and glass ionomer are the two dental materials used for placing fissure sealants. Being white or colourless, fissure sealants are not usually visible after they have been placed into the mouth. Glass ionomer sealants are intended only as a temporary measure as they are not as long lasting as resin sealants. They are usually applied to teeth that are difficult to isolate from saliva as they are more forgiving than resin if there is some saliva contamination during application. Resin dental sealants must be placed in a completely dry environment and they can last as long as five to ten years.
How are Fissure Sealants Applied?
The biting surfaces of the teeth are first cleaned by a gel to allow
the resin to bond with the teeth. The
sealant is then applied in liquid form to seal the grooves on the biting
surfaces of these teeth and set hard with an ultraviolet light. Glass iononer sealants are applied as a paste and are self-setting.
Can Dental Sealants Prevent Tooth Decay?
Pit and fissure
caries account for about 90% of tooth decay in children. They originate in the grooves
of the molar and premolar teeth. By sealing the grooves of the molars and premolars with fissure sealants, this type of tooth decay can usually be prevented. The teeth should be sealed with fissure sealants as soon as they erupt into the mouth as this when they are most susceptible to caries attack.
The teeth are protected from pit and fissure caries because fissure sealants block the entry of bacteria and food particles into the grooves. Fissure sealants are the only way to protect the grooves from decay because fluoride cannot penetrate the grooves. Toothbrush bristles are also too large to fit into the grooves to clean them properly.
In order for fissures sealants to be effective, they must be placed properly. Fissure sealants are also only effective against tooth decay that originate in the pit and fissures. They have no effect on tooth decay that occur on the smooth surfaces of the teeth.
Although the indication for dental sealants is most often the grooves of children’s molar teeth, they can also be applied to the molars of adult teeth in adults who are considered high risk for developing pit and fissure caries. It is believed that the teeth are most susceptible to pit and fissure caries upon eruption into the mouth. This susceptibility generally decreases the longer the tooth has been in the mouth.
Fissure sealants protect teeth against pit and fissure caries because they prevent bacteria from entering the grooves of newly erupted molars and premolars from tooth decay. Without the sealant barrier, bacteria reside within the grooves where they are relatively protected from other measures aimed at clearing the bacteria. Fluoride does not penetrate the grooves and tooth brushing is not effective because the bristles are often larger than the grooves in the teeth. It is also difficult to detect early
pit and fissure caries until considerable damage has been done. Additionally, fissure sealants are easy to place, non-invasive and very cost effective.
Tooth decay that begins in the pit and fissures of the molar often progress unchecked and undetected. This is because dentine is more susceptible to decay than enamel. When tooth decay begins in the grooves of the teeth, the dentine is rapidly undermined while the enamel may remain largely intact until a considerable portion of the dentine has been undermined. Without the supporting dentine beneath it, the enamel collapses to form a cavity. There may be possible nerve involvement and the treatment for fixing the tooth becomes more costly and involved.
Prevention is better than cure.F issure sealants provide an excellent preventative measure for protecting the teeth against tooth decay arising in the pits and fissures of molar and premolar teeth. The procedure is easy, fast, minimally invasive and very cost effective. Fissure sealants are recommended as one of the first lines of defenses for preventing tooth decay.