For what main purpose are pit and fissure sealants applied?

Pit and fissure sealants are primarily applied to prevent cavities in the depressions and grooves on the tooth surface. These areas are particularly susceptible to plaque accumulation and decay due to their complex structure, which makes it difficult for regular brushing to clean them effectively. By sealing these pits and fissures with a protective coating, sealants form a barrier that inhibits bacteria and food particles from settling in these vulnerable areas, thereby reducing the risk of caries formation.

In contrast, the other options do not accurately reflect the therapeutic purpose of sealants. While whitening teeth or improving aesthetic appearance can be achieved through other dental treatments, they are not the primary function of sealants. Additionally, sealants do not repair existing damage to enamel; instead, they serve a preventive role, focusing on protecting healthy tooth surfaces from future decay.