skin tissue engineering

Question 1

1. What are the disadvantages of skin autografting?

Answer 1

• the donor site is a new wound
• this can cause bleeding, infection, nerve damage
• scarring and pigmentation changes occur
• dermis is not replaced
• donor site is a potential site for infection
• donor site is not unlimited
• extensive burns makes it impossible

Question 2

2. What are the three categories of skin substitutes?

Answer 2

• epidermal substitutes
• dermal substitutes
• dermo-epidermal substitutes

Question 3

3. What are the three layers of the skin?

Answer 3

epidermis, dermis, hypodermis

Question 4

4. Name 3 functions of the human skin

Answer 4

1. Protect underlying tissues from injury: mechanical, heat, cold, biological.
2. Prevent excess water loss.
3. Act as a temperature regulator.
4. Serve as a reservoir for food and water: adipose tissue
5. Assist in the process of excretion: H20, Salt, Urea, Lactic Acid.
6. Serve as a sense organ for cutaneous senses: pain, heat, cold, pressure, touch.
7. Prevent entrance of foreign bodies: microorganisms.

Question 5

5. What are the three burn classifications? How do they all differ?

Answer 5

1st degree- involves top layer of epidermis only

2nd degree- skin blister, involves all of epidermis and dome of dermis, may involve all of the dermis

3rd degree- may extend into deeper tissues

Question 6

6. Explain how Integra heals skin injuries

Answer 6

it is composed of two layers, the bottom layer of collagen fibers that create the basis of a scaffold for dermal cells and the top layer of a protective silicone film that can be removed one the dermal layer has been established

when it is applied to the wound site the skin regenerates and grows naturally

Question 7

7. Name three general design properties of tissue engineered skin.

Answer 7

cost should not prelude the use of the device

it should protect the wound by providing a barrier to the outside

it should control water evaporation and protein and electrolyte loss

it should decrease pain

the risk of infection must be taken into account

it should provide an environment for accelerated wound healing

Question 8

** What is alpigraf ?

Answer 8

its a company that make bi-layer skin substituents. this product has living cells and structural proteins that aid in tissue repair. often geared toward foot ulcers.