What is the role of enamel in teeth?

Enamel plays a crucial role in dental health by providing a protective surface on the crown of the tooth. This outer layer is the hardest substance in the human body and serves as a barrier against physical damage and chemical erosion from acids produced by bacteria or dietary sources. The protective nature of enamel helps prevent cavities and other forms of tooth decay by shielding the underlying dentin and pulp from harmful influences.

The other options relate to functions that are not performed by enamel. Saliva production is primarily regulated by salivary glands, not enamel. Nutrient absorption occurs in the gastrointestinal tract rather than within the teeth. While the cushioning effect during biting is important, it is primarily the role of the underlying tissues, such as the periodontal ligament and the pulp, instead of enamel. Thus, enamel's primary function is indeed to provide a durable and protective exterior for teeth.