When a child’s permanent front teeth first emerge, parents often notice small, bumpy ridges along the biting edge of the incisors. This scalloped or wavy appearance is a normal part of dental development. These formations are temporary structures that help the tooth during its eruption process.
What Are Those Ridges Called and How Do They Form?
The small ridges found on the biting edge of newly erupted permanent incisors are known as mamelons. The word mamelon is derived from the French word for “nipple,” referring to the distinct, rounded bumps. These formations are a byproduct of how teeth are built, originating from the developmental stages before the tooth breaks through the gums.
Each front tooth crown develops from three or four distinct lobes of enamel, not as a single unit. The mamelons are the remnants of these individual developmental lobes before they fully fuse together. Typically, three mamelons are visible on each incisor, giving the tooth its characteristic wavy appearance. This structure may also help the tooth pierce through the overlying gum tissue more easily during eruption.
The Natural Lifespan of Tooth Ridges
Mamelons are designed to be temporary, eventually wearing down through the normal use of the teeth. The act of the upper and lower teeth coming into contact gradually smooths the enamel surface. These ridges wear away faster than the rest of the enamel because they protrude and take the initial impact of biting forces.
For most children, the mamelons disappear naturally within weeks or months of the permanent tooth erupting. This natural smoothing process is a sign that the teeth are being used actively and are developing a uniform biting edge. However, the ridges may persist longer if the child has a bite misalignment or an open bite where the front teeth do not make consistent contact. In these cases, the natural wear does not occur, and the ridges can remain visible into adolescence or even adulthood.
When Ridges Indicate a Different Issue
While mamelons are generally harmless, some ridge-like formations or surface irregularities may point to different dental conditions. One such condition is enamel hypoplasia, where the tooth enamel is deficient in quantity or thickness. This condition manifests not as the three uniform bumps of a mamelon, but often as pits, grooves, or missing enamel that can appear horizontally across the tooth surface.
Another concern is severe wear patterns, which can sometimes be mistaken for persistent mamelons, especially if they are uneven. Excessive wear can be a sign of bruxism, or teeth grinding. Parents should seek a dental evaluation if the ridges appear discolored, if the child reports pain or sensitivity, or if the mamelons persist significantly longer than expected, as this may indicate an underlying bite alignment issue.