What is the primary purpose of a dental sealant?

The primary purpose of a dental sealant is to prevent decay in the grooves of teeth. Dental sealants are thin, protective coatings that are applied to the chewing surfaces of the back teeth (molars and premolars), where food particles and plaque can accumulate and lead to cavities. These grooves are often difficult to clean effectively with a toothbrush alone, making them susceptible to decay. By sealing these surfaces, the sealants create a barrier that helps to protect the enamel from acids and bacteria, significantly reducing the risk of cavities.

The definitions of other options clarify their distinct purposes: whitening teeth is typically achieved through bleaching and does not provide any protective benefits against decay; replacing a lost tooth usually involves prosthetic solutions such as implants, bridges, or dentures, which do not directly relate to decay prevention; and aligning teeth involves orthodontic treatments, which address the positioning of teeth rather than their enamel protection against cavities.