the dermis

Examples of the dermis in the following topics:

• Blood Supply to the Epidermis

  • The blood vessels in the dermis provide nourishment and removes waste from its own cells and from the Stratum basale of the epidermis.
  • The epidermis does not contains blood vessels; cells in the deepest layers are nourished by diffusion from blood capillaries present in the upper layers of the dermis which provide nourishment and waste removal from the cells of the dermis, as well as for the cells of the epidermis.
  • The dermis is the layer of skin beneath the epidermis that consists of connective tissue and cushions the body from stress and strain.
  • The dermis is tightly connected to the epidermis by a basement membrane.
  • Control of blood supply to the dermis forms part of the bodies thermoregulatory capacity.

• Structure of the Skin: Dermis

  • The dermis consists of a papillary and a reticular layer that serve to protect and cushion the body from stress and strain.
  • Lying underneath the epidermis—the most superficial layer of our skin—is the dermis (sometimes called the corium).
  • The dermis is a tough layer of skin.
  • The dermis is composed of two layers.
  • Beneath the dermis is the deepest layer of our skin.

• Epidermal Wound Healing

  • Epidermal only wounds are typically less severe than those affecting the dermis and so stages of the wound healing response may be missed.
  • As the epidermis is itself not vascularised, instead receiving blood from the dermis, a clotting and vasonstrictive response is often not necessary.
  • Immune cells may still be recruited to the wound site, as with the removal of the epidermal barrier the wound is susceptible to infection.
  • As the dermis is intact local fibroblasts are able to contribute to the formation of a new basement membrane, upon which the epidermis sits.
  • As the dermis and underlying tissue have not been damaged very little remodelling is required.

• Tattoos

  • A tattoo is a form of body modification, made by inserting indelible ink into the dermis layer of the skin to change the pigment.
  • A tattoo is a form of body modification, made by inserting indelible ink into the dermis layer of the skin to change the pigment.
  • The first written reference to the word, "tattoo" (or Samoan "Tatau") appears in the journal of Joseph Banks, the naturalist aboard Captain Cook's ship, the HMS Endeavour: "I shall now mention the way they mark themselves indelibly, each of them is so marked by their humor or disposition".
  • A healthy patient will get the best results.
  • A tattoo is a form of body modification, made by inserting indelible ink into the dermis layer of the skin to change the pigment.

• Effects of Aging on the Integumentary System

  • Intrinsic and extrinsic aging describe cutaneous aging of the integumentary system primarily involving the dermis.
  • Intrinsic aging and extrinsic aging are terms used to describe cutaneous aging of the skin and other parts of the integumentary system.
  • While having some effects on the epidermis, such aging seems to primarily involve the dermis .
  • Such an aging process may include qualitative and quantitative changes such as diminished or defective synthesis of collagen and elastin in the dermis.
  • In younger skin, sun damage will heal faster since the cells in the epidermis have a faster turnover rate, while in the older population the skin becomes thinner and the epidermis turnover rate for cell repair is lower which may result in the dermis layer being damaged.

• What is Skin?

  • The cutaneous membrane is the technical term for our skin.
  • In order from most superficial to deepest they are the epidermis, dermis, and subcutaneous tissue.
  • This layer is found only on the palms of the hands, fingertips, and the soles of the feet. 
  • The deepest layer of the skin is called the subcutaneous layer, the subcutis, or the hypodermis. 
  • Like the dermis, the layer contains blood vessels and nerves for much the same reasons. 

• Skin and Mucosae (Surface Barriers)

  • The epidermis also helps the skin regulate body temperature through sweat pores that connect to underlying sweat glands in the dermis.
  • The basement membrane: a thin sheet of fibers called the basement membrane, that seperates the dermis and epidermis.
  • It controls the traffic of cells and molecules between the dermis and epidermis but also controls the release of cytokines and growth factors during wound healing for the skin.
  • The dermis: the layer of skin beneath the epidermis that consists of connective tissue and cushions the body from stress and strain.
  • The blood vessels in the dermis provide nourishment and waste removal from their own cells as well as for the epidermis.

• Deep Wound Healing

  • A deep wound involves the inner/deeper layers of the skin (dermis).
  • A deep wounds which damage the dermis, or even the underlying muscle and fat are more difficult to heal than shallow epidermal only wounds.
  • However, with removal of the dermis and associated skin appendages re-epithelialization can only occur from the wound edge, with no contribution from the dermal compartment.
  • As such, proper re-constitution of the epidermis is often only seen at the edge of the wound, with fibrous scar tissue formed from the extracellular matrix deposited (ECM) during the proliferative phase covering the rest of the wound site.
  • With the formation of a scar the original physiological properties of the tissue are lost.

• Lines of Cleavage and Surgery

  • Cleavage lines are topological lines drawn on a map of the human body and correspond to the orientation of collagen fibers in the dermis.
  • They correspond to the natural orientation of collagen fibers in the dermis.
  • The lines were first described in 1861 by Austrian anatomist Karl Langer, though he cited the surgeon Baron Dupuytren as being the first to recognize the phenomenon.
  • He noticed that the resultant punctures in the skin had ellipsoidal shapes.
  • They follow the main fibres of the connective tissue of skin.

• Burns

  • Most burns affect only the first two layers of the skin, the epidermis and dermis.
  • In the latter system, burns are classified as first, second, third, or fourth degree burns based on the depth of injury to the dermis.
  • Second degree burns extend into the superficial papillary dermis .
  • Third degree burns extend through the entire dermis .
  • The majority of these fatalities occur either at the scene or on the way to hospital.