Research on the osteogenic properties of 3D-printed porous titanium alloy scaffolds loaded with Gelma/PAAM-ZOL composite hydrogels

Although titanium alloy is the most widely used endoplant material in orthopedics, the material is bioinert and good bone integration is difficult to achieve. Zoledronic acid (ZOL) has been shown to locally inhibit osteoclast formation and prevent osteoporosis, but excessive concentrations of ZOL exert an inhibitory effect on osteoblasts; therefore, stable and controlled local release of ZOL may reshape bone balance and promote bone regeneration. To promote the adhesion of osteoblasts to many polar groups, researchers have applied gelatine methacryloyl (Gelma) combined with polyacrylamide hydrogel (PAAM), which significantly increased the hydrogen bonding force between the samples and improved the stability of the coating and drug release. A series of experiments demonstrated that the Gelma/PAAM-ZOL bioactive coating on the surface of the titanium alloy was successfully prepared. The coating can induce osteoclast apoptosis, promote osteoblast proliferation and differentiation, achieve dual regulation of bone regeneration, successfully disrupt the balance of bone remodelling and promote bone tissue regeneration. Additionally, the coating improves the metal biological inertness on the surface of titanium alloys and improves the bone integration of the scaffold, offering a new strategy for bone tissue engineering to promote bone technology.