Perceiving the connection between the bone healing process and biodegradation of biodegradable metal implants through precise bioadaptability principle

The implants made of metallic biomaterials help healing the bone fracture but also affect the bone repair process. As proposed in Matter 4 (2021) 2548–2650 by Wang et al., a precisely adaptable biomaterial ought to recapitulate the targeted tissue with spatiotemporal precision and hierarchical accuracy, ranging from atoms and molecules (genes, proteins, etc.) to cells (including organelles) and to tissues and organs. In comparison to traditional bio-inert metallic bone implants such as Co-based alloys and Ti alloys, biodegradable metal (Mg and Zn alloys) bone implants had been developed and might arise many unexpected variables in the bone repair, due to their bioactive nature. In this paper, the bone repair without and with the presence of metallic implants is compared. Thereafter, the perspectives concerning the interactions between the bone tissues and biodegradable metal implants are put forward, and how to better mimic in vivo biodegradation by in vitro experiments is proposed for further research and development of biodegradable metals.