Japanese researcher's 'tooth regrowth' treatment to begin human trials
Researcher Katsu Takahashi's paper in 2021 about a tooth regeneration medication grabbed global attention. Back then, Takahashi's research was done on ferrets but is now expected to be trialed in humans as early as next year, the Japanese national daily, The Mainichi reported.
It is generally assumed that the human race can grow sets of teeth in their lifetime. After the "milk teeth" fall, humans develop what is referred to as permanent teeth that must be cared for since their only replacements are artificial dentures or implants.
Research, however, has shown that human jaws have buds for a third set of teeth but, for some reason, do not grow to maturity. In contrast, animals like sharks and certain reptiles can continuously regrow their teeth, and dentists like Takahashi have been keen to explore if the same can be achieved in humans too.
Not just a cure for cavities
Takahashi's zeal to grow a new set of teeth on demand might sound like a scientific excess when more straightforward approaches like brushing twice a day, flossing, and mouthwash exist in abundance to protect permanent teeth.
But his approach goes well beyond the common dental problems that ail us. Anodontia, for instance, is a disorder where individuals cannot grow a complete set of teeth. This isn't a case of a child eating too many sweets but a genetic condition that they might be born with and affects their ability to chew, swallow, and even speak, thereby impacting their development.
Takahashi studied dentistry but was also interested in the underlying genetics of these conditions, so studied molecular biology at Kyoto University and in the US.
Block a protein, grow more teeth
Researchers have begun making links between dental conditions and various genes. One research group found that mice grew fewer teeth when specific genes were deleted. On his return from the US, Takahashi's team at Kyoto University found that mice lacking a gene had more teeth.

The gene codes for a protein called USAG-1 which is responsible for limiting the growth of teeth. Blocking the protein could allow the researchers to grow more teeth.
Takahashi's team then developed an antibody that could target the USAG-1 protein. The antibody was trialed in mice in 2018 and showed new teeth coming through.
The team then replicated its research in ferrets with dental patterns similar to humans. These findings were then published in 2021, which received global acclaim as a "tooth regeneration treatment."
Now the research team is working to get the antibody into human clinical trials, which are scheduled to begin in July 2024. The antibody will be administered to children between the ages of two and six affected by anodontia.
If the trials go as per plan, it will open up a whole new world of dental treatments which rely on synthetic dentures and implants.
In the not-so-distant future, one can grow a new set of teeth when the "permanent" one is lost.