Final answer:
The destruction of tooth enamel by microorganisms is referred to as caries, or dental cavities, which result from acids released by bacteria like Streptococcus mutans feeding on sugars.
Step-by-step explanation:
The term given to the destruction of the outer portion of the tooth (enamel) by microorganisms is caries, also known as tooth decay or cavities. Dental caries develop when bacteria in the mouth, particularly the cariogenic species Streptococcus mutans, feed on sugars and release acids. These acids lead to the degradation of the calcium crystals in the enamel, causing soft tissue inflammation and dental decay.
When caries are not treated promptly, they can penetrate deeper into the tooth, affecting the dentin and potentially leading to an infected pulp or abscess. Treatment for dental caries includes removing the decayed areas and filling them, or performing a root canal procedure if the infection has reached the pulp.