Biomaterials 101



  • 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


  • 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