Wouldn’t it be amazing if there were a technology that could cure infected or damaged bones? A technology that could safely restore people to their original health after breaking their bones? Although this treatment may seem impossible, it exists.
There have been many experiments conducted exploring the restorative powers of bioactive glass. Bioactive glass is a compound that causes osteogenesis, or the regrowth of bone. It is completely safe, and due to its chemical makeup, it is able to incorporate itself into the human body.
So how exactly does bioactive glass work? According to Antonio Tilocca from the Department of Chemistry at the University College of London, the molecular compounds that make up the glass begin to dissociate from each other. Next, calcium and phosphate ions from the bioactive glass start to form a layer around the surrounding bone. This layer matches the layer that is created when bones grow normally. The body thinks that the covering is the layer created by a bone, and thus responds by initiating the process of bone regrowth.
The history of bioactive glass began much earlier than you might think. Bioactive glass research started as early as the 1960s, explains Kaur, a scientist from Thapar University in India. Between the late 1970s and early 1980s, bioactive glass research skyrocketed when a group of scientists in Japan, under the leadership of Professor Yamamuro, completed 3,000 vertebral surgeries, 20,000 hip bone surgeries, and 12,000 spinal surgeries, all of which incorporated bioactive glass. In 1985, a bioactive glass implant for bones inside the ear was created, which proved successful in curing hearing loss, and thus became highly advertised. Today, however, the vast majority of the bioactive glass that is used is in dental care.
Although successful research has been conducted with bioactive glass for over half of a century, few people outside of the biomedical community know about this solution. Before reading this article, you probably had not heard of bioactive glasses. Did you think that bioactive glasses must be some sort of optical aid?
This is a problem, because with more awareness, bioactive glass use would increase beyond simply providing dental support; it would help patients recover from more serious injuries, such as a broken femur or an infected vertebra, applications which have been researched but rarely implemented. Awareness will also result in an increase in research. This is important for causing further development in bioactive glasses, making their use more effective and cheaper.
Examining specific case studies demonstrates the benefits of bioactive glass. For patients who need the lower vertebrae of their back fused together, bioactive glass provides a perfect solution. Scientist Ido and fellow surgeons undertook this procedure. By surgically placing bioactive glass in the area where bone fusion is needed, the bones and the bioactive glass will grow together, making the lower back stronger. Another benefit of using bioactive glass in vertebrae fusion is that less autologous bone graft is needed. Autologous bone graft is when bone from one part of a person’s body is removed and used somewhere else. In this situation, bone graft is taken from the hip bone and placed in the vertebrae.
More recent research demonstrates how modifying bioactive glass can make it even more durable and effective.
In most bioactive glass research, simple elements are used to make up the glass, including oxygen, hydrogen, silicon, calcium, and phosphorous. However, some scientists are taking a step further. Research conducted by scientist Valentina Aina using bioactive glass with gold nanoparticles (AuNPs) has shown new benefits. Gold provides increased strength and durability, which is great for the regrowth of bone. The addition of gold had another interesting benefit: it had the ability to repair DNA in connective tissue cells. This is important because it shows how bioactive glass can be utilized to provide more benefits than simply mending bones.
There are still more uses for bioactive glasses. Rather than stimulating bone regrowth, Xia and Chang from the Chinese Academy of Science found that the glasses can be used to deliver medication to bones. This aspect of bioactive glass is vital, because with our current methods of injecting or ingesting medicine, bones do not directly receive it. To solve this issue, scientists have been able to model mesoporous bioactive glass, which means that the glass has microscopic pores that can be filled with the desired drug.
The future of bioactive glass is full of innovation and advancement. Even with their fascinating benefits today, there are many possible uses of these functional compounds that are waiting to be discovered. This writing only explores the tip of the iceberg. With more research and development, the number of solutions to bone related issues will be greatly increased. Imagine breaking your collar bone, but not being the least bit concerned because you know it can be healed in a couple of days. Or perhaps your mother has been diagnosed with osteoporosis, but with the help of newly developed mesoporous bioactive glass, she is soon given a clean bill of health. These scenarios will occur, but not without increased awareness and support. Further development will allow bioactive glass to help thousands of people, not only repairing bones, but also bringing loved ones back to their families and friends.
by: A. Knudsen
References
Aina, Valentina et al. (2013). Gold-containing bioactive glasses: A solid-state synthesis to produce alternative biomaterials for bone implantations. Journal of the Royal Society Interface, 10(82): Retrieved from https://dx.doi.org.libproxy.lib.unc.edu/10.1098%2Frsif.2012.1040.
Hench LL and Jones JR (2015). Bioactive glasses: Frontiers and challenges. Front. Bioeng. Biotechnol. 3: Retrieved from http://journal.frontiersin.org/article/10.3389/fbioe.2015.00194/full.
Ido, K, et al. (2000). Radiographic evaluation of bioactive glass-ceramic grafts in postero-lateral lumbar fusion. Spinal Cord, 38(5), 315-318: Retrieved from https://www.nature.com/sc/journal/v38/n5/pdf/3100992a.pdf.
Kaur, G, et al. (2016). An introduction and history of bioactive glasses. In: Marchi J. (eds) Biocompatible Glasses, 53, 19-47: Retrieved from https://link.springer.com/content/pdf/10.1007%2F978-3-319-44249-5_2.pdf.
Tilocca, Antonio, et al. (2007). The structure of bioactive silicate glasses: New insight from molecular dynamics simulations. Chemistry of Matter, 19(1), 95-103: Retrieved from http://pubs.acs.org/doi/full/10.1021/cm061631g#citing.
Xia, Wei and Jiang Chang. (2006). Well-ordered mesoporous bioactive glasses (MBG): A promising bioactive drug delivery system. Journal of Controlled Release, 110(3), 522-530: Retrieved from http://www.sciencedirect.com/science/article/pii/S0168365905006127.