Anatomy Of The Fingernail
Posted in: General info by weddingcometrue | February 28th 2010 | no comments
The nail has a few important functions: it acts as a shield for the fingertip, augments the sensitivity of the fingertip, it can also be used to pick up small objects and even as a defensive weapon. Although the fingernail has mainly a functional purpose, it is also viewed as an important asset in a person’s image.
The anatomy of the fingernail:
Fingernails grow continuously but their growing rate can become lower with age and bad circulation. Fingernails growing rate is 3 mm per month which is faster than the toenails’ 1 mm per month. While a fingernail can be replaced in about 6 months, it takes 12 to 18 months to completely replace a toenail.
The anatomy of the fingernail is concerned with six distinctive parts: the root, nail bed, nail plate, cuticle (eponychium), paronychium and hyponychium. A particular function is assigned to each of these parts and the disruption of any of them can lead to abnormalities in the fingernail.
The nail’s root is also called the germinal matrix. This section of the nail is hidden under the skin and stretches several millimeters into the finger. The root of the fingernail is responsible for producing most of the mass of the nail and the nail bed. This part of the nail does not have any melanin producing cells, also called melanocytes . The white, moon shaped structure at the base of the visible fingernail, called the lunula, represents the edge of the germinal matrix.
The portion that stretches from the lunula to the hyponychium is the sterile matrix or nail bed. Blood vessels, nerves and melanocytes can be found in the nail bed. The fingernail is produced by the root along the nail bed, which also makes it thicker as it is added under the surface of the nail. The nail bed has to be smooth so that the growing nail can flow down smoothly along its surface. Otherwise the fingernail can split or develop channels, which can have an unpleasant look.
The actual visible fingernail is called the nail plate and it is made of translucent keratin, a tough protein. The blood vessels under the nail give it a pink appearance. Channels underneath the nail plate function as anchors to the nail bed.
The portion that blends the skin of the finger with the nail plate is called a cuticle or eponychium. The role of the cuticle is to provide a waterproof barrier.
The tissue of skin that surrounds the border of the fingernail is the paronychium or the paronychial edge. The paronychium can become infected because of ingrown nails. The infection of the paronychium is called paronychia.
The hyponychium is found under the free edge between the nail plate and the fingertip and it carries out a waterproof role.