Biomaterials 101
Definitions
Biomaterial
- A natural or synthetic material that is suitable for introduction into living tissue.1 This definition does not address function.
- A synthetic material used to replace part of a living system or to function in intimate contact with living tissue.2
- A biomaterial is a substance that has been engineered to take a form which, alone or a part of a complex system is used to direct, by control of interactions with components of living systems, the course of any therapeutic or diagnostic procedure.3
Scaffold
- Temporary framework used to support people and material in the construction or repair of buildings.
- In regenerative medicine the more commonly used definition is: “An artificial structure capable of supporting 3-D tissue formation.”4
- To allow bone formation a scaffold should allow: attachment, proliferation, migration, and phenotypic expression of bone cells leading to formation of new bone in direct apposition to the Ca-P biomaterial.2,5
Scaffold purpose 6-9
- Allow cell attachment and migration
- Deliver and retain cells and biochemical factors
- Enable diffusion of vital cell nutrients and expressed products
- Exert certain mechanical and biological influences to modify the behavior of the cell phase differentiation
Depending on application a scaffold must be 6-9
- Biocompatible and biodegradable
- Mechanically stable over time
- Able to incorporate any chemical, or biological cues desired
- Adequate permeable to allow fluid flow and diffusion
- Unable to elicit an inflammatory reaction
The ideal scaffold should be:
- Should be implantable through a minimal surgical exposure
- Applicable for various indications
- Should be moldable to conform to and fill irregular defects
- Should posses roughly the same visco-elasticity as bone
- Should be as rigid and strong as intact bone for immediate load-bearing capability
- Should promote new bone formation and incorporation by host bone
- Should be available in large quantities and it should be cheap
- DOES NOT EXIST!