Embedded in the dermal layer of the skin, epidermal burn of hand exposed bright colours of tattoo.
Tattoos are created by injecting ink into the skin of a person, involving placement of a pigment into the dermis of the skin. The pigment disperses through the epidermis and upper dermis through a homogenised damaged layer. The epidermis is separated from the dermis by an extracellular network of collagen fibers known as the basement membrane which serves as a support framework for the cells. The purpose of the basement membrane is to prevent tearing from excessive stretching by strengthening the interface. This article describes the case of an epidermal burn exposing the bright colours of a tattoo.
The process of tattooing causes damage to the epidermis, topmost layer of dermis and the epidermal-dermal junction. These layers are like a mush, or in other words, homogenized right after the process of tattooing. Initially, the ink disperses in the upper dermis as fine granules, however, after 7 to 13 days, it aggregates into more concentrated areas. The pigment is dispersed through a homogenized damaged layer down the upper dermis and epidermis; the presence of foreign materials, in both cases, activates the immune system and the phagocytes engulf the pigment particles.
The damaged epidermis flakes away as the healing proceeds – eliminating the surface pigment.
Granulation tissue forms in the deeper skin which is later converted to connective tissue by collagen growth. In addition, like any other injury, the initial response is to stop the bleeding followed by swelling of the tissue and migration of non-resident immune cells. Immune cells include macrophages and neutrophils, these phagocytic cells clean up the area by swallowing the debris and leave via the lymphatics. The upper dermis is mended with this process and within the successive generations, the pigment stays trapped ultimately concentrating in a layer below the epidermis and dermis boundary, as revealed after the epidermal burn. The presence of the pigment is stable, moreover, in the long term, the pigment tends to migrate deeper which accounts for the degrading of old tattoos1.
Unless an allergic reaction occurs or there are signs of an infection, this is the extent of the immune response.
Fibroblasts, regenerate and repair the tissue, the tissue formed initially is known as granulation tissue, fresh, soft and pinkish scar which later matures into an old scar with fibrous tissue. The ink is taken up by phagocytic cells including mast cells, macrophages, fibroblasts and keratinocytes. In a month’s time, the epidermal-dermal junction reforms and the basal cells contain ink.
Ink containing phagocytic cells in the dermis are concentrated along the junction of the epidermis and dermis surrounded by collagen, just below the granulation tissue. The ink is eliminated through the epidermis with ink present in fibroblasts, macrophages and keratinocytes2. The epidermis fully reforms after two to three months and prevents any further loss of ink through the epidermis. Most of the ink is located below the layer of fibrous tissue which is replaced by granulation tissue. The fibroblasts are effectively trapped in connective tissue. These fibroblasts are believed to give tattoos their lifespan.
- Wood-Black, F. (2017). Going skin deep: the culture and chemistry of tattoos. Dostupné z: https://inchemistry. acs. org/content/inchemistry/en/atomic news/tattooink. html.
- Grant, C. A., Twigg, P. C., Baker, R., & Tobin, D. J. (2015). Tattoo ink nanoparticles in skin tissue and fibroblasts. Beilstein journal of nanotechnology, 6(1), 1183-1191.