Tooth implants, although a great improvement over false teeth, are far from perfect. Expensive and time-consuming to manufacture, they lack long-term durability. Pezhman Mohammadi, a research scientist from the Center for Young Synbio Scientists at VTT Technical Research Center of Finland is doing his post-doctoral research on bio-composites and their use as implants. Not only are these materials superior to those currently used for dental implants, they also are less expensive and more environmentally-friendly.
Over time, dentistry has made great advances as new technologies and materials become available, from gold to porcelain to mercury to modern composites. With new materials have come new applications, such as tooth implants. As teeth fail, dentists are able to screw a replacement tooth (an implant) into place. In the long run, this saves many teeth, because the remaining healthy teeth are not extracted to make way for a full set of dentures.
However, there is room for improvement in both the manufacturing processes and the implants themselves.
Currently, implants are prohibitively expensive for many people. The manufacturing cost of implants are high for a variety of reasons. Starting materials are expensive as are the fabrication methods. The process is time-consuming and requires intense heat or high downstream energy consumption, which also drives up the cost, in addition to creating a large carbon footprint. Implants are now typically made of porcelain in a two-component system, which can result in failure due to a mismatch of properties. These materials are also not durable over time under the extreme conditions that can occur in mouths, such as a low or high temperature, a high alkaline, a high acidic, or a high salt environment. And finally, current implants can be prone to plug formation and infection due to biocompatibility issues.
At VTT, Pezhman Mohammadi is working with a team of scientists to solve these problems by developing new types of high performance biological materials. These multiphase nanocomposites are both lightweight and impact resistant, making them perfect for dental applications. The molecular design, assembly routes, and overall architecture of these novel materials are inspired by high-performance structural biomaterials found in nature. Proteins, in particular, have a unique capacity to form interactions and molecular organizations with almost any type of material. This flexibility enables the creation of unique materials tailored for their nanoarchitectures, mechanical performance and adhesive properties.
Although these newly developed multiphase biocomposite materials are “constructed” out of both organic and inorganic materials, the most crucial component is a unique set of proteins which Mohammadi and his team have engineered and recombinantly produced in microorganisms through biotechnology. These proteins are entirely new, with no analogue in nature, and their mechanical properties are unprecedented. Both strong and tough, they are engineered in such a way that deposition and initiation of mineral growth can be controlled to produce any intricate architecture or shape desired. Additionally, they are produced at ambient temperature (22c) and use water as a solvent. These unique properties could enable cheaper, more durable implants that are less prone to complications. And the conditions required to produce them have a much smaller carbon foot-print than current implants require.
In addition to influencing dentistry, the bio-composites this research has yielded are anticipated to have a substantial impact on Finland’s bioeconomy via a potential spin-off company.