denticle

A denticle is a small tooth-like projection or serration on a surface. The term, derived from the Latin dens for tooth, is used across biology and paleontology to describe tiny, tooth-shaped structures that are usually smaller and simpler than a true tooth.

In cartilaginous fishes such as sharks and rays, denticles refer to dermal denticles—tiny, tooth-like scales that cover the skin. Each denticle typically has an enamel-like cap over a dentine base, and its shape varies among species. Dermal denticles contribute to reduced hydrodynamic drag and increased skin durability, and their patterns can aid in species or individual identification in some contexts.

In paleontology and comparative anatomy, denticles often describe serrations along the edge of a tooth. These edge denticles are common on theropod dinosaur teeth and on teeth of some extinct sharks. The size, density, and morphology of denticles are frequently used in taxonomic descriptions and functional interpretations, including wear patterns and feeding mechanics.

More broadly, denticle can refer to any small tooth-like projection on bone, mucosa, or other tissues when described in comparative anatomy. The term is thus applied in diverse fields to denote tiny, tooth-resembling ridges, nodules, or serrations that inform structure and function.