ABSTRACT
The nail plate is the permanent product of the nail matrix. Its normal appearance and growth depend on the integrity of the perionychium and the bony phalanx (Figure 2.1).1 The nail is a semihard horny plate, relatively smooth, covering the dorsal aspect of the tip of the digit curved in both the longitudinal and transverse axes. In the ventral aspect of the nail, longitudinal ridges are present that correspond to the complementary ridges of the nail bed. The nail is inserted proximally in an invagination that is practically parallel to the upper surface of the skin and laterally to the lateral nail grooves. This pocket-like invagination has a roof, the proximal nail fold and a oor, the matrix from which the nail is derived. Newborn nails mostly reach the end of ngertips but seldom reach the end of toes. The shapes of the nails vary from one child to another. The ngernails and toenails do not necessarily resemble each other.2
