Is It Possible to Regrow Human Teeth?

By Mehmood Asghar, Ph.D.

Tooth loss is a global problem that affects people of all ages and nationalities. According to the World Health Organization, the global prevalence of edentulism in individuals aged 20 or over is 7%. Furthermore, over 23% of the global population older than 60 years has lost all their teeth.

Replacement Teeth Aren't Natural Teeth

Currently, the options available for replacing missing teeth are removable dentures, teeth bridges, and implants. Unfortunately, none of these tooth replacement options are as good as natural teeth. This is precisely why scientists have been trying for many decades to find a way to regrow human teeth with varying levels of success. Recently, there's been a breakthrough, as a Japanese pharmaceutical company seems to have discovered a way to regrow lost human teeth.

The Breakthrough

The Japanese pharmaceutical company Toregem Biopharma, along with Kyoto University, has developed a new drug based on the research of Dr. Katsu Takahashi, who is an oral and maxillofacial surgeon at Kyoto University, Japan. The concept is relatively simple. Toregem Biopharma has developed an antibody drug that utilizes undeveloped tooth buds in adults to regrow an entire human tooth.

But how does the antibody work? It simply follows nature. Babies are born with tooth buds that ultimately develop into teeth. However, in some cases, adults retain undeveloped tooth buds, which can be used to grow natural teeth. This is exactly what this drug does.

Diving Into the Details

This drug exerts its effect by interacting with the uterine sensitization associated gene-1 (USAG-1) (Ravi et al., 2023). This gene is expressed in odontogenic epithelial cells and is an antagonist of bone morphogenic proteins and the Wnt-signaling pathway glycoproteins. Interestingly, studies have shown that mice deficient in the USAG-1 gene tend to have supernumerary teeth (Murashima-Suginami et al., 2007; Murashima-Suginami et al., 2008). Based on the same principle, ferrets grew new teeth when they were given this drug in a 2018 study.

The researchers who have developed this antibody drug plan to conduct clinical trials in 2025. Children with anodontia aged between 2 and 5 who are born with some missing teeth will be inducted into this study. One dose of the drug will be injected into these children to promote teeth formation. The company also plans to use this drug on adults to grow lost teeth.

Drug Discovery

For Honoka Kiso, D.D.S., Ph. D., the President of Toregem, the motivation behind the discovery of a drug for tooth regrowth was a bone disease that led to tooth loss during her teenage years. "I wanted to study the cause of my illness and how to regenerate lost teeth. Toregem Biopharma first hopes to treat patients with congenital tooth loss who do not grow permanent tooth buds due to genetic causes. Our final goal is to offer advanced and scientifically driven clinical solutions for the growth of teeth derived from their own tissues," Kiso said.

The Future of Tooth Regeneration

"Missing teeth in a child can affect the development of their jawbone," said Katsu Takahashi, co-founder of Toregem Biopharma and head of dentistry and oral surgery at Kitano Hospital in Osaka. More importantly, they can affect one’s smile, facial appearance, and self-confidence.

With the development of this new drug, the possibility of regrowing lost or congenitally missing teeth seems very near to realization. Further research in this area is expected to help find more avenues and possibilities in dental tissue regeneration, thereby eliminating the need for prostheses for missing teeth replacement.

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Author: Dr. Mehmood Asghar is a dentist by profession and an Assistant Professor of Dental Biomaterials at the National University of Medical Sciences, Pakistan. Dr. Asghar received his undergraduate and postgraduate dental qualifications from the National University of Science and Technology (NUST). He is also currently pursuing a Ph.D. in Restorative Dentistry from Malaysia. Apart from his hectic clinical and research activities, Dr. Asghar likes to write evidence-based, informative articles for dental professionals and patients. Dr. Asghar has published several articles in international, peer-reviewed journals.

References

Murashima-Suginami, A., Takahashi, K., Kawabata, T., Sakata, T., Tsukamoto, H., Sugai, M., Yanagita, M., Shimizu, A., Sakurai, T. & Slavkin, H. C. 2007. Rudiment incisors survive and erupt as supernumerary teeth as a result of USAG-1 abrogation. Biochemical and biophysical research communications, 359, 549-555.

Murashima-Suginami, A., Takahashi, K., Sakata, T., Tsukamoto, H., Sugai, M., Yanagita, M., Shimizu, A., Sakurai, T., Slavkin, H. C. & Bessho, K. 2008. Enhanced BMP signaling results in supernumerary tooth formation in USAG-1 deficient mice. Biochemical and biophysical research communications, 369, 1012-1016.

Ravi, V., Murashima-Suginami, A., Kiso, H., Tokita, Y., Huang, C. L., Bessho, K., Takagi, J., Sugai, M., Tabata, Y. & Takahashi, K. 2023. Advances in tooth agenesis and tooth regeneration. Regenerative Therapy, 22, 160-168.