What dental feature is defined by three round protuberances on the incisal edge of newly erupted anterior teeth?

The feature described as three round protuberances on the incisal edge of newly erupted anterior teeth is known as mamelons. These are small, rounded bumps that can be observed on the incisal surfaces of incisors, particularly when they first emerge into the oral cavity. Mamelons typically appear shortly after tooth eruption as a result of the development of the tooth and represent the lobes of the tooth that have not completely fused during formation.

As the teeth undergo wear through normal function, these mamelons often smooth out and become less visible over time. This characteristic can be an important indicator of a tooth’s eruption stage and is particularly noted in primary dentition as well as the early phases of permanent teeth.

In contrast, other terms such as cingulum, fossa, and cusp refer to different dental structures. The cingulum is a convexity on the lingual surface of anterior teeth, a fossa is a depression or concavity in the surface of a tooth, and a cusp typically refers to the pointed or rounded projections on the occlusal surface of posterior teeth. Each of these features serves different roles in dental anatomy and function, distinguishing them from mamelons.