The drug, called TRG-035, works by blocking a special protein named USAG-1. This protein usually stops new teeth from growing. By blocking it, the scientists have found a way to activate hidden tooth buds, helping teeth grow again.
In earlier tests on animals like mice and ferrets, the drug showed great results. It helped them grow completely new teeth that looked and worked just like their natural ones. Now, scientists have moved on to testing the drug on humans.
The first trial is happening at Kyoto University Hospital in Japan. It began in October 2024 and includes 30 adults aged 30 to 64, each missing at least one tooth. The main goal of this trial is to check if the drug is safe for people to use.
If this first step is successful, the next trial will test the drug on children who were born without permanent teeth. The hope is to make this treatment available to everyone by the year 2030.
Dr. Katsu Takahashi, who leads the research and works at the Medical Research Institute Kitano Hospital in Osaka, has been studying this for years. He said, “The idea of growing new teeth is every dentist’s dream. I’ve been working on this since I was a graduate student. I was confident I’d be able to make it happen.”
The scientists discovered that the USAG-1 protein stops tooth growth by interacting with other signals in the body. When they blocked this interaction, they were able to trigger a process known as BMP signaling, which leads to the growth of new teeth.
After testing the drug on mice, they moved on to ferrets. The ferrets grew a new front tooth that looked just like their natural teeth. These successful results gave the team the confidence to begin human trials.
This treatment could be especially helpful for people who suffer from a condition called tooth agenesis, which means they are born without some of their teeth. This condition affects about 1% of the population and can make it hard to eat or speak properly. Many children with this condition have to get dentures or implants at a young age, which can be uncomfortable and difficult to manage.
The researchers believe that TRG-035 could help children as young as 2 to 6 years old who do not have adult teeth. Instead of giving them implants, doctors may be able to help them grow their own natural teeth.
“TRG-035” is given through an injection and is designed to block the USAG-1 protein. When this protein is blocked, tooth buds in the mouth can start growing again. These are buds that usually stay inactive after our baby and adult teeth come in.
Most people grow two sets of teeth in their lifetime—baby teeth and adult teeth. But animals like sharks and crocodiles can grow thousands of teeth throughout their lives. For a long time, scientists thought humans didn’t have the ability to grow more teeth after the adult set.
But recent studies have shown that we may have a third set of tooth buds that just stay quiet due to the USAG-1 protein. By blocking that protein, this new drug might help those hidden buds start growing.
Dr. Chengfei Zhang says the idea is revolutionary but must be carefully tested. Professor Angray Kang from Queen Mary University in London called it “exciting and worth pursuing,” but warned that it’s “not a short sprint, but back-to-back ultra-marathons.”
There are also important rules and safety steps the team must follow. Before TRG-035 can be sold or used widely, it will need to pass many checks to make sure it’s safe for long-term use. Making it affordable and available to people all over the world is also something researchers are thinking about.
If everything goes well, the team hopes to make this medicine available to the public by 2030. It could be a new option alongside dentures and implants—offering a natural and painless way to regrow teeth.
“In any case, we’re hoping to see a time when tooth-regrowth medicine is a third choice alongside dentures and implants,” Dr. Takahashi added.
