Dentin is a hard, dense tissue that forms the bulk of a tooth, lying beneath the outer enamel and surrounding the inner pulp. It is primarily composed of mineralized matrix, which gives it strength, and is less hard than enamel but more resilient. Dentin contains tiny tubules that connect to the pulp, allowing for sensation and nutrient exchange. This tissue plays a crucial role in tooth health and function. When enamel is damaged or worn away, dentin becomes exposed, leading to increased sensitivity and a higher risk of decay. Proper dental care, including regular visits to a dentist, is essential to maintain the integrity of dentin and overall tooth health.