what do cavities look like, Cavities, also known as dental caries or tooth decay, can appear as small holes or pits on the surface of a tooth. They may also manifest as dark or discolored spots, ranging from light brown to black. When cavities progress, they can cause tooth sensitivity, pain, and visible damage to the enamel. Regular dental check-ups and good oral hygiene practices, like brushing and flossing, are essential to detect and prevent cavities.