Description

Pits and fissure sealants are dental protective coatings applied to the deep grooves and depressions (pits and fissures) on the chewing surfaces of molars and premolars to prevent tooth decay. They form a physical barrier that blocks accumulation of bacteria and food debris in these hard-to-clean areas, reducing the risk of dental caries. Composition and Materials: The two main types of pit and fissure sealants are resin-based and glass ionomer sealants. Resin-based sealants are primarily composed of resin monomers like bisphenol A-glycidyl methacrylate (Bis-GMA) or urethane dimethacrylate (UDMA), inorganic filler particles such as silica or glass, photoinitiators, pigments, and polymerization initiators and accelerators. These sealants are preferred due to their superior retention and durability. Glass ionomer sealants bond chemically to enamel and dentin, release fluoride over time, and are less sensitive to moisture during placement, making them useful when ideal isolation is difficult. Resin-based sealants require an acid-etching procedure for micro-mechanical bonding to the enamel, typically using 37% orthophosphoric acid gel. Sealants can be autopolymerizing (chemically cured) or photopolymerizing (light-cured), with light-curing being commonly used for better control over setting time. Function: Sealants fill and seal the narrow, deep fissures and pits on teeth surfaces, especially those with narrow or constricted morphologies that are susceptible to caries. By sealing these depressions, they prevent bacterial colonization and protect the enamel from acids produced by plaque bacteria. Glass ionomer sealants additionally provide fluoride release for ongoing caries prevention. Clinical Considerations: Resin-based sealants offer better longevity and retention but require a dry field for placement. Glass ionomer sealants are advantageous in moist environments but may have lower retention rates. The choice of sealant depends on patient-specific factors, clinical conditions, and moisture control availability. In summary, pits and fissure sealants are preventive dental materials mainly made of resin or glass ionomer compounds designed to protect susceptible tooth surfaces by sealing out cariogenic factors, thereby preventing dental caries in these vulnerable areas