Researchers in Japan testing drug to regrow teeth

Dormant buds of a third generation of teeth are hidden under the gums, says researcher

TOKYO - People with missing teeth may be able to grow new ones, said Japanese dentists testing a drug they hope will offer an alternative to dentures and implants.

Unlike reptiles and fish, which usually replace their fangs on a regular basis, it is widely accepted that humans and most other mammals grow only two sets of teeth.

But hidden underneath people's gums are the dormant buds of a third generation, according to Dr Katsu Takahashi, head of oral surgery at the Medical Research Institute Kitano Hospital in Osaka.

His team launched clinical trials at Kyoto University Hospital in October, administering an experimental medicine to adult test subjects that they noted has the potential to jump-start the growth of these concealed teeth.

It is a technology completely new to the world, said Dr Takahashi.

Prosthetic treatments used for teeth lost to decay, disease or injury are often seen as costly and invasive.

So, "restoring natural teeth definitely has its advantages", said Dr Takahashi, the project's lead researcher.

Tests on mice and ferrets suggest that blocking a protein called USAG-1 can awaken the third set.

The researchers have published lab photographs of regrown animal teeth.