| Antibacterial effects | Immunomodulatory effects | Advantages | Limitations | Ref |
---|---|---|---|---|---|
Ag | · Disrupt membranes by binding to sulfhydryl groups · Damage DNA and protein by oxidative stress · Bind directly to nucleic acid molecules and hinder cell growth and reproduction | · Induce M1 polarization of macrophages and exacerbate the inflammatory response · Promote M2 polarization of macrophages, ROS scavenging, and new bone formation (in very low doses) · Induce death of host cells | · Direct and broad-range antibacterial effects · High stability · Mature techniques available for incorporation in implants | · Toxicity for eukaryotic cells | |
Ga | · Replace iron in bacterial metabolism · Aggregate at the site of inflammation | · Inhibit bone resorption by inhibiting osteoclast activity · Promote osteogenic gene expression in MG63 cells · Reduce the inflammatory response of the wound | · Unique antibacterial mechanism · Inhibit bone resorption · Aggregate spontaneously to the site of infection | · Unstable antibacterial effect influenced by iron concentration · Fewer molecular mechanism studies currently · High cost | |
Zn | · Damage DNA and protein by oxidative stress · Disrupt the cell walls/membranes | · Enhance phagocytosis and chemotaxis of macrophages · Mediate PGRPs exert antibacterial activity · Promote immune cell maturation · Anti-inflammatory effects by deregulating NF-κB pathway activity | · Pro-osteogenic effects described · Significant immune regulation function · Essential trace elements | · Weak direct antibacterial effects | |
Cu | · Disrupt membranes by binding to sulfhydryl groups Generate ROS through Fenton reactions · Disrupt helix structure of DNA | · Facilitate M1 macrophage switch and bacteria phagocytosis to resist infection · Induce a proper immune environment for bone regeneration · Induce angiogenesis | · Direct and broad-range antibacterial effects · Fenton reaction catalyst · High stability · Essential trace elements · Significant angiogenic and osteogenic abilities | · Toxicity at supraphysiologic concentration | |
Mg | · Inhibit bacterial adhesion and biofilm formation due to Elevated pH by Mg degradation · Inhibit biofilm-forming genes and protein expression in the outer membrane of bacteria | · Stimulate M2 macrophage switch and inhibit osteoclastogenesis and osteolysis · Downregulate pro-inflammatory cytokines and induce osseointegration · Protect neutrophils from endogenous oxidative stress | · Essential element for bone tissue · Excellent anti-inflammatory and pro-osteogenic activity | · Poor corrosion resistance · Poor inherent antibacterial properties |