Biocompatibility Evolves: Phenomenology to Toxicology to Regeneration

The word biocompatibility, is inconsistent with the observations of healing for so-called biocompatible biomaterials. The vast majority of the millions of medical implants in humans today, presumably biocompatible, are walled off by a dense, avascular, crosslinked collagen capsule, hardly suggestive of life or compatibility. In contrast, one is now seeing examples of implant biomaterials that lead to a vascularized reconstruction of localized tissue, a biological reaction different from traditional biocompatible materials that generate a foreign body capsule. Both the encapsulated biomaterials and the reconstructive biomaterials qualify as biocompatible by present day measurements of biocompatibility. Yet, this new generation of materials would seem to heal compatibly with the living organism, where older biomaterials are isolated from the living organism by the dense capsule. This review/perspective article will explore this biocompatibility etymological conundrum by reviewing the history of the concepts around biocompatibility, today's standard methods for assessing biocompatibility, a contemporary view of the foreign body reaction and finally, a compendium of new biomaterials that heal without the foreign body capsule. A new definition of biocompatibility is offered here to address advances in biomaterials design leading to biomaterials that heal into the body in a facile manner.

Automated summary

The term biocompatibility does not always align with the healing observations of biomaterials. Traditional biocompatible materials result in the formation of a foreign body capsule, while newer biomaterials can lead to vascularized tissue reconstruction.