Researchers working on drug to regrow teeth

Japanese researchers may have found the solution to the nightmare of toothless smiles, by testing a drug that could allow incisors and other molars to grow back.

No more dentures on the bedside table or hefty bills for dental implants? Japanese dentists believe in it and are testing a new drug which, they hope, will become an alternative to dentures and implants.

Unlike reptiles and fish whose fangs are replaced regularly, humans, like most other mammals, only grow two sets of teeth, milk teeth and the aptly named “permanent” teeth.

But hidden beneath our gums are the dormant buds of a third generation, according to Katsu Takahashi, head of the oral surgery department at the Kitano Hospital Medical Research Institute in Osaka.

In October, Takahashi and his team launched human clinical trials of an experimental drug with the potential to jumpstart the growth of these hidden teeth.

This “entirely new” technology is designed to neutralize a protein called USAG-1, which inhibits the growth of the third set of teeth, the researcher explains to AFP.

Current prosthetic treatments used for teeth lost due to decay, disease or injury are often considered expensive and invasive.

“Regrowing natural teeth definitely has benefits,” says Takahashi.

In a study published last year, the team said, with supporting photos, that its “antibody treatment in mice is effective in tooth regeneration and may represent an advance in the treatment of dental abnormalities in humans. ‘man”.

For now, dentists are prioritizing “urgent” cases of patients with six or more teeth missing at birth.

The hereditary condition is thought to affect about 0.1% of people, who can have severe difficulty chewing and, in Japan, often spend most of their adolescence wearing a face mask to hide the large holes in their mouth, Mr. Takahashi.

“This drug could be a game-changer for them,” he hopes.

The drug would therefore be intended primarily for children, and the researchers want to make it available from 2030.

Angray Kang, professor of dentistry at Queen Mary University of London, knows of only one other team pursuing a similar goal. “But I would say that the Takahashi group is leading the way,” this immunotechnology expert told AFP.

Takahashi’s work is “exciting and worth pursuing,” in part because an antibody drug that targets a protein almost identical to USAG-1 is already used to treat osteoporosis.

“The race to regenerate human teeth is not a sprint, but a series of ultra-marathons. And this is just the beginning,” he says.

According to Chengfei Zhang, a clinical professor of endodontics at a Hong Kong university, Takahashi’s method is “innovative and has potential.”

“The assertion that humans have latent tooth buds capable of producing a third set of teeth is both revolutionary and controversial,” he told AFP.

This bud can be explained by the fact that the residues of the human dental blade sometimes lead to a surplus of teeth according to him.

The results of past animal experiments raise “questions about the ability of regenerated teeth to functionally and aesthetically replace missing teeth,” he continues.

In response, Takahashi argues that if a new tooth grows incorrectly, it can be replaced through orthodontics or transplantation.

Currently, participants in these clinical trials are adults, who are missing only one tooth and tooth regeneration is not the primary objective of this trial.

According to Takahashi, there is a small chance of this happening to the test subjects but the researcher “would be over the moon if it happened.”

The drug’s arrival on the market would be particularly welcome in Japan, which has the second oldest population in the world.

Health Ministry data shows that more than 90% of Japanese aged 75 or older have at least one missing tooth.

“We strongly hope that our technology can directly extend their healthy life expectancy,” hopes Mr. Takahashi.