Additional information related to content in Chapter 59 can be found on the companion Evolve Web site.
and Multimedia Procedures DVD
Acrylate (AK-ri-layt) A salt or ester of acrylic acid.
Dental sealant Coating that covers the occlusal pits and fissures of teeth.
Filled resin (REZ-in) Sealant material that contains filler particles.
Microabrasion (air abrasion) Technique used to open fissures before sealant placement.
Microleakage (mye-kroe-LEE-kuj) Microscopic leakage at the interface of the tooth structure and the sealant or restoration.
Polymerization (puh-LIM-ur-i-zay-shun) Process of changing a simple chemical into another substance that contains the same elements.
Sealant retention Sealant firmly adhering to the tooth surface.
Unfilled resin (REZ-in) Sealant material that does not contain filler particles.
Dental sealants represent one of the greatest advances in modern dentistry. Unfortunately, too many children, particularly low-income children, do not receive the protective benefits of dental sealants. The purpose of a dental sealant is to prevent dental caries in the pits and fissures. Dental sealants are clear protective coatings that are easily applied; they cover the tooth surface, preventing bacteria and food particles from settling into the pits and fissures (grooves) of the teeth (see Chapter 8).
Although fluoride has caused the overall rate of dental caries to drop, the greatest benefits from fluoride occur on the smooth surface of the enamel. The pits and fissures of the teeth do not benefit from the effects of fluoride as much as smooth enamel surfaces do. Scientific studies have proved that properly placed dental sealants are 100 percent effective in protecting development of cavities in sealed tooth surfaces.
How Sealants Work
The narrow width and uneven depth of pits and fissures make them ideal places for the accumulation of food and acid-producing bacteria. Saliva, which helps to remove food particles from other areas of the mouth, cannot clean deep pits and fissures. Pits and fissures are often deep, narrow channels in the enamel surface that can extend close to the dentinoenamel junction (Fig. 59-1). The enamel that lies at the base of the fissures is thinner than the enamel around the rest of the tooth. This means that deep narrow fissures can make it more likely that tooth decay will occur, and any decay that does form will penetrate through the thin enamel and progress more quickly into the pulp.
Pits and fissures on the teeth are so tiny that even a single toothbrush bristle is too large to enter for cleaning purposes (Fig. 59-2).
The sealant acts as a physical barrier that prevents decay (Fig. 59-3). Small food particles and plaque (bacteria) cannot penetrate through or around a sealant. As long as the sealant remains intact, the tooth is protected. However, if part of the sealant or bond is broken, the sealant protection is lost.
Sealants are not as widely used as they should be among low-income children (utilization of sealants is only about 30 percent); this is the high-risk group that could benefit the most from sealants.
In many states, application of dental sealants is a duty that may be delegated to the educationally qualified dental assistant (see Procedure 59-1 later in this chapter).