Researchers successfully implant and innervate bioengineered teeth derived from postnatal cells.
Tooth loss is a major public health issue affecting more than 158 million people worldwide. The current standard of care is to replace missing teeth with synthetic dental implants, and fixed or removable prosthetics. While successful in some cases, thesed treatment options are inferior to natural teeth with many associated complications. Therefore, research has been focusing on the formation of bioengineered whole tooth replacement therapies which can provide both the function and sensory responsiveness of natural teeth. Now, two preclinical studies develop innervated, bioengineered tooth bud constructs whose features resemble natural tooth buds, which were implanted subcutaneously into rats without the use of immunosupressors. The teams state this is the first report to describe the use of postnatal dental cells to create bioengineered tooth buds which exhibit features of natural tooth development. The studies were published in Journal of Dental Research, they can be found here and here.
Previous studies show that stem cell-based tissue engineering is a promising approach to replace or repair lost or damaged tissues or even organs in humans. Two major types of stem cells currently used in tissue engineering research are embryonic stem cells and postnatal stem cells. However, ethical concerns remain in using embryonic stem cells and difficulties in isolation, expansion, and differentiation of postnatal stem cells limit their clinical application. The current studies implants bioengineered teeth without using an immunosuppressant, and supplies nerves to them.
The first study develops cellularized bioengineered tooth bud constructs from postnatal dental cells which form hallmark features of natural tooth buds such as the dental epithelial stem cell niche, enamel knot signaling centers, transient amplifying cells, and mineralized dental tissue formation. Results show that these constructs were encapsulated within a hydrogel material which were then successfully implanted subcutaneously into immunocompromised rats.
The second study utilises autologous mesenchymal cells coming from bone marrow to supply nerves to bioengineered teeth without using an immunosuppressor. The lab state that the innervation of teeth is essential for their function and protection, and does not occur spontaneously after injury.; this new method provides innervation while avoiding multiple side effects associated with immunosuppressors.
The team surmise they have successfully used postnatal dental cells to develop bioengineered tooth buds which exhibit features of natural tooth development, and used autologous mesenchymal cells to innervate the bioengineered teeth without treatment with an immunosuppressor, thus avoiding multiple side effects. For the future, the researchers propose future innervated, bioengineered tooth buds as a promising, clinically relevant tooth replacement therapy.