Resin-Based Sealants

Resin-based sealants (RBSs) are cured with visible light. When using light cured materials, it is very important that the curing light is of high quality and is tested frequently for the value of the light emitted. The majority of RBSs are not fluoride releasing, resin is hydrophobic, and their application is more technique sensitive (moisture concerns). If the tooth surface cannot be kept free of moisture contamination from saliva, blood, or water, RBSs should not be used. Contamination of resin will lead to more rapid marginal leakage and sealant failure. Over time, acid can contribute to marginal breakdown and microleakage under the sealant, which can contribute to decalcification and cavitation underneath. Retention loss of RBSs is associated with the risk of developing caries.⁶ Some RBSs claim to release fluoride, but the fluoride release is minimal at the initial placement, and does not continue over time because fluoride ions are incapable of moving through chemically inert resin. In the mid-1990s safety concerns were expressed regarding leaching of bisphenol-A (BPA) from the sealants and a possible estrogenic effect. However, studies have concluded that the short term risk of estrogenic effects from treatments using BPA resins is insignificant and that BPA released orally may not be absorbed at all or may only be present in nondetectable amounts in the systemic circulation.^7,8

Dental material manufacturers offer a variety of resin-based sealant materials designed to meet the preferences of individual operators. These products include sealant materials that are unfilled, filled, opaque, clear, colored, and products that change color when cured. Convenient unit-dosed material is also available. There appears to be no difference in the retention rate. The filled materials are often easier to see and monitor, but the clear materials allow the operator to continue to see the fissures. Sometimes operators prefer the colored sealants to make monitoring retention easier. Patients and parents should be consulted prior to the placement of colored sealants. The dental personnel should be aware of the filler content in the sealant being utilized. The higher the percentage of filler, the more important it is to check and adjust the occlusion when the sealant is high in occlusion.⁹ It is very important that the curing light penetrates the sealant being placed to ensure maximum polymerization.