Explain about Bioactive materials

Bioactive materials: Certain glasses, ceramics, and glass-ceramics that contain oxides of silicon, sodium, calcium and phosphorus (SiO₂ , Na₂O, CaO, and P₂O₅ ) form a chemical bond with bone, resulting in a strong mechanical implant bone bond. These materials do bond to bone through a time-dependent, kinetic modification of the surface triggered by their implantation within living bone. An ion-exchange reaction between the bioactive implant and surrounding body fluids results in the formation of a biologically active calcium phosphate layer on the implant. This layer is chemically and crystallographically equivalent to the mineral phase in bone which is responsible for the strong interfacial bonding.