In Sci-fi visions of distant futures, some imagine sprawling intergalactic civilizations. Scaffolds built around stars harvest their energy. Fusion reactors, cyborgs, superintelligent implants. But the future of artificial bones, though perhaps more mundane, could be a life-saving science. Millions of patients each year require bone grafts. Physical trauma, degenerative diseases, and infections can all require interventions to replace damaged bone structures. This article aims to explore the medical literature on artificial bones and the potential future of their science.
The State of the Art
The gold standard of modern bone grafting is autografting. This is the process of extracting a patient’s own bone from one location and grafting it into another. This process ensures perfect histocompatibility, meaning there is no chance of the bone being rejected by the body for having different alleles, or genetic markers by which the body recognizes friend from foe. In addition, there’s no risk of transferring diseases when the donor bone comes from the patient. A patient's own bone also operates perfectly in terms of osteoinductivity and osteoconductivity. That is to say, our own bones operate to stimulate the growth of new bone from stem cells, and they act as a scaffold to which new bone can easily attach properly. That said, in many cases, patients may find themselves incapable of receiving autographs. This can be because the damage is too extensive to be repaired through an autograft or other conditions, such as osteoporosis, which makes a bone brittle and reduces its ability to heal, causing an autograft to be a less effective option.
In the cases where an autograft would be ineffective, oftentimes metallic or plastic bone replicas are used. In the field of biomaterials, polymers, ceramics, and metals have all been used as bone implants with various drawbacks. Polymers can be custom 3D printed to match a patient's exact needs, offering a tailored solution to their exact needs. That said, these same polymers lack the strength of ceramics and metals. Ceramic solutions can be more osteoconductive and biodegradable, potentially making them more compatible with the preexisting skeleton, but ceramics are brittle and cannot be used in places which are expected to bear heavy loads. Finally, metals can be tough and resistant to fracturing, which can make them ideal for replacements that see repeated heavy loads, but do not promote bone regrowth. This can lead to “stress shielding,” a process where a metal implant bears all the load of an activity instead of the natural bone it's connected to. This can lead the bone to degrade and loosen the connection to the implant.
Growing Replacements
An ideal alternative to biomaterial implants in research is custom-growing artificial bones from the patient's own stem cells. This method could theoretically provide all the benefits of an autograft, but reduce the time spent healing while being feasible in a much wider variety of circumstances. Epibone is one company working on this problem. Epibone takes a CT scan of the site of the defect and then uses the patient’s own stem cells in a bioreactor, which acts as an incubator replicating conditions within the body to stimulate external growth. The result of this is that Epibone can create artificial bone and cartilage to be implanted within the human body.
Beyond growing artificial bone to end the need for bone transplants, medical science in growing artificial bones could result in producing artificial blood. At the University of Basel, in November of 2025, scientists successfully recreated a miniaturized human bone marrow. This involved not just regrowing the bone structure, or scaffolding, but the inner culture of bone cells, nerves, blood vessels, as well as other cell types. This artificial bone structure was capable of producing blood for a number of weeks. Researchers hope that this development will help scientists better study blood cancers and how other defects in the production of blood occur. Furthermore, they hope their artificial bone marrows can be used to reduce the need for animal experimentation in the same domain.
Artificial Bones and Their Potential Future
Where some dream of a future where humanity colonizes Mars, I dream of a future that harnesses the true potential of artificial bones. According to the Red Cross, every two seconds, someone needs a blood or platelet transfusion. Artificial bones could provide a future where bones grow,n and blood is produced in surplus.
Just as valuable as the blood itself would be an artificial bone to produce immune system cells, such as white blood cells and T-cells. White blood cells are fully produced in the bone marrow, and the precursors of T-cells are also produced in the bone marrow before maturing in the thymus, a specialized gland in the immune system. The potential of artificial bone to enable an externally produced blood, complete with additional immune cell cultures, could have radical implications for reducing medical mortalities.
In the treatment of infections and cancers, powerful antibiotics and chemotherapy can often be employed. These treatments have the dangerous downside of harming the patient’s immune system as well. In antibiotics, this occurs because they are bactericidal or bacteriostatic, meaning they kill bacteria or stop bacteria from multiplying. Unfortunately, this also impacts healthy bacteria that form our microbiomes, which can support our immune systems. In the case of chemotherapy, treatments often target rapidly dividing cells, which can make them myelosuppressive, meaning they obstruct the bone marrow’s ability to produce white blood cells.
Imagine a future where every hospital on earth has a room of artificial bones. Not just producing a clean surplus of blood for transfusions, but externally producing a slurry of blood complete with a supplemental immune system. Immunocompromised individuals might be able to supplement for their condition. Patients undergoing chemotherapy not only maintain a healthy immune system throughout their treatments, but could even have a stronger immune system grown for them artificially to help the patient fight off their cancer.
Conclusion
The production of artificial bone is a valuable field of science that has already made significant strides. It is already possible, to some extent, to grow artificial bone structures to replace the need for biomaterials, which, though highly effective, can have tradeoffs. Meanwhile, future developments in growing bones complete with marrow may be a precursor to growing artificial blood or even supplemental immune cells.
