Tissue Scaffolds

Question 1

Explain the tissue scaffold principle

Answer 1

Tissue scaffolds provide a structure to either hold cells in place or for cells to grow and proliferate.

Natural tissues contain cells and an extra-cellular matrix (ECM). Composition of ECM varies with tissue.

Main tissue engineering principle is Biomimetic design - Creating a porous structure that mimics the ECM

Question 2

What are the requirements of an ideal scaffold

Answer 2

Biocompatibility - Interact positively with the host environment

Biodegradability - Degrade into non-toxic materials with a controlled degradation rate that matches the regeneration rate of native tissue

Adequate Porosity, micro and macrostructure - high porosity, adequate pore size

Adequate Mechanical strength - if degradation is too fast, the load is transferred to the tissue before sufficient growth, if too slow, regenerating tissue is shielded from stresses

Adequate surface properties
Formability

Question 3

What is the most common 3D-printed scaffold material? List properties as well

Answer 3

Thermoplastic polymers
Solid at room temp and viscous liquids when heated
They can be easily and economically shaped
They can be subjected to heating and cooling cycles without significant degradation

Thermosets can’t tolerate repeated heating and cooling cycles

Question 4

How are tissue scaffolds made?

Answer 4

3D printing