What is a key benefit of sealants in preventive dentistry?

Sealants are a vital component in preventive dentistry primarily because they help prevent caries, specifically on the occlusal surfaces of teeth, which are the chewing surfaces of molars and premolars. These surfaces are prone to decay due to their complex anatomy, which includes pits and fissures where food particles and plaque can accumulate. By applying a sealant, a thin protective coating is created that seals these vulnerable areas, reducing the risk of bacteria and plaque build-up. This significantly lowers the likelihood of the development of cavities in these areas.

While enhancing the cosmetic appearance of teeth can be a benefit in some contexts, it is not the primary function of sealants. They do not fix cavities, as that would typically require restorative procedures like fillings, and they do not strengthen tooth enamel, which involves different preventive measures or treatment options. The primary function of sealants is specifically to provide a barrier against decay, making option B the most accurate choice regarding their key benefit in preventive dentistry.