Medication for Tooth Regrowth Could Soon Become a Reality

According to the United States Centers for Disease Control and Prevention, approximately one in six adults aged 65 or older is edentulous. And when permanent teeth fail, there is no tooth fairy to console us. In lieu of a quarter left under our pillows when we lose our adult teeth, we might be facing down an implant, bridge, or dentures.

Unlike some other species, humans do not grow an unending supply of teeth. Though there have been cases of individuals regenerating a third round of teeth, for the most part, when adult teeth are lost, the only way to replace them today is via appliances. All can come with certain drawbacks. If only there was a way for us to regrow our own teeth.

Thanks to ongoing studies, that day may not be far off.

SHARKS DO IT

Some species on the planet, sharks for instance, do enjoy tooth regeneration. The prospect of tooth regeneration has long intrigued the research community, with studies ranging from stem cell use and tissue engineering to gene manipulation.

But recent tooth regeneration research by scientists at Kyoto University and the University of Fukui in Japan that began by regrowing teeth in mice and ferrets may be the winning ticket. The researchers have developed a medication that would allow humans to mirror some animals such as sharks and some reptiles that are able to regenerate dentition continuously. In fact, human trials may begin as early as next year.¹

FINDING THE OFF SWITCH

The research team, led by Katsu Takahashi, head of the Dentistry and Oral Surgery Department at the Medical Research Institute Kitano Hospital, found that mice that lacked a certain gene had more teeth. They discovered that when a protein called USAG-1 (uterine sensitization associated gene-1), which limits tooth growth, was blocked, bone morphogenic protein (BPM) signaling was enhanced and the mice grew more teeth. The researchers then tried it on ferrets, which have dental patterns similar to humans. The results were similar.¹

Through systematic application of a USAG-1 neutralizing antibody, they were able to regenerate a third dentition in ferrets. This leads them to suggest that targeted molecular therapy may be the key to stimulating tooth regeneration. However, they stress that the clinical application of this modality will require further investigation in nonrodent models.¹

Pending continued successful outcomes, the scientists believe that targeted molecular therapy for tooth regeneration can be a viable therapeutic approach.

POSSIBLE CHALLENGES

Some have expressed concern about the ability to control the shape, location, and number of teeth that regrow, and how all of this will translate to use in humans.

The initial plan is to test the medicine on people lacking a full set of teeth due to congenital issues. Once it’s clear there are no adverse effects in humans, they’ll treat children ages 2 to 6 who have adontia.²

Takahashi believes that in most cases, humans’ ability to grow a third set of teeth has been lost over time. “We’re hoping to see a time when tooth-regrowth medicine is a third choice alongside dentures and implants,” he said.²

The researchers are hoping to offer the medicine for general use by 2030.

References

1. Murashima-Suginami A, Kiso H, Tokita Y, et al. Anti-USAG-1 therapy for tooth regeneration through enhanced BPM signaling. Sci Adv. 2021;7:eabf1798.
2. Nagira M. World’s 1^st ‘tooth regrowth’ medicine moves toward clinical trials in Japan.