Scientists have identified a drug that may stimulate a dormant third set of teeth to grow in humans — a discovery that could one day change how we replace missing teeth. The research is still in clinical trials, but early results are genuinely exciting for the future of dentistry.
- Most people have a vestigial “third dentition” — a dormant set of tooth buds that normally never activate.
- Japanese researchers are testing a drug (anti-USAG-1 antibody) that may “wake up” these buds, potentially allowing adults to grow new natural teeth.
- Human clinical trials began in 2024; results so far show the drug appears safe, but growing a full functional tooth in adults is still years away from reality.
- Right now, the best ways to replace missing teeth remain dental implants, dental bridges, and dentures — all of which we offer at Vaksman Dental Group.
- The discovery is also a fascinating reminder of why protecting the teeth you have now matters more than ever.
A headline in Popular Mechanics recently stopped a lot of people mid-scroll: “Humans Have a Third Set of Teeth. New Medicine May Help Them Grow.” It sounds almost too good to be true — like something from a sci-fi novel. But the science behind it is real, peer-reviewed, and genuinely worth understanding. Let’s dig in.
Wait — Do Humans Really Have a Third Set of Teeth?
Sort of, yes — and this is one of the coolest things about human biology. You already know about your two sets: your baby (primary) teeth, which you lose as a child, and your permanent (adult) teeth, which are meant to last a lifetime. But researchers have known for years that most humans carry a set of dormant tooth buds — essentially the genetic “blueprint” for a third dentition that never gets activated under normal circumstances.
These buds are a bit of an evolutionary leftover. Our ancient ancestors had multiple sets of teeth (think sharks, which cycle through teeth continuously). Over millions of years of evolution, humans gradually lost that regenerative ability — but the underlying genetic machinery isn’t entirely gone. It’s just switched off.
A small percentage of people do spontaneously grow extra permanent teeth — a condition called hyperdontia — which hints that this latent potential is real. Most of the time, though, those third-dentition buds stay quietly dormant.
What’s the New Drug, and How Does It Work?
Researchers at Kyoto University and Fukui University in Japan have been studying a protein called USAG-1 (Uterine Sensitization-Associated Gene-1), which acts as a molecular “off switch” for tooth growth. USAG-1 suppresses the signals that would otherwise tell a third tooth bud to develop.
Their breakthrough: an antibody drug that blocks USAG-1. In animal studies (mice and ferrets), blocking this protein allowed new teeth to grow. The results were compelling enough that Japanese researchers moved into human Phase 1 clinical trials in 2024, primarily targeting people with anodontia — a rare condition where people are born missing some or all of their permanent teeth.
According to reporting from Popular Mechanics and coverage in the journal Science Advances, the early Phase 1 trial data suggests the drug appears safe in humans. But — and this is an important “but” — we’re still a long way from a dentist being able to prescribe a pill that grows you a new molar.
What Does “Clinical Trials” Actually Mean for a Timeline?
Clinical trials move in phases for good reason: safety first, then effectiveness, then large-scale testing. Here’s a realistic honest breakdown:
| Trial Phase | What It Tests | Where the Tooth-Growing Drug Is Now |
|---|---|---|
| Phase 1 | Is it safe in humans? | ✅ Underway (began 2024) |
| Phase 2 | Does it actually work in humans? | 🔜 Not yet started |
| Phase 3 | Large-scale effectiveness & safety | 🔜 Years away |
| Regulatory Approval | Government clearance for use | 🔜 Best-case mid-2030s or later |
The honest answer: if everything goes perfectly, a tooth-growing drug might be available to the public sometime in the 2030s — and even then, likely first for people with severe congenital tooth loss, not as a routine alternative to implants. The researchers themselves have been careful to temper expectations.
Why Is This Discovery Such a Big Deal, Even If It’s Years Away?
Because it represents a fundamentally new category of dental treatment. Almost everything we do to replace missing teeth today is mechanical — we put in a titanium post (dental implants), we make a bridge out of porcelain, we craft a denture from acrylic. These are excellent, time-tested solutions that genuinely change people’s lives. But none of them are biological — none of them are your actual tooth, with its living root and natural shock absorption.
If this drug works as hoped, it could mean that instead of replacing a missing tooth with an artificial one, we could coax your own body into growing a real one. That’s a paradigm shift — the dental equivalent of regrowing a limb.
It also opens doors for children born with hypodontia (missing teeth from birth), adults who lose teeth to injury or disease, and eventually perhaps even people who simply want to replace a worn-out molar.
What Should You Actually Do About Missing Teeth Right Now?
Here’s the practical takeaway: even the most optimistic researchers aren’t telling people to wait on a tooth-growing pill. Missing teeth cause real, progressive problems — bone loss in the jaw, shifting of neighboring teeth, changes in bite and facial structure — and these begin surprisingly quickly after a tooth is lost.
The American Dental Association’s MouthHealthy resource consistently recommends replacing missing teeth promptly. Today’s options are genuinely excellent:
- Dental implants — the gold standard; a titanium root topped with a lifelike crown that can last decades with good care.
- Dental bridges — a fixed option that spans the gap, anchored to neighboring teeth.
- Dentures and partial dentures — removable, affordable, and more comfortable than ever with modern materials.
- All-on-4 implants — for people missing most or all of their teeth, a full arch of teeth supported by just four implants.
At Vaksman Dental Group, our dental team works with patients across South San Francisco, San Bruno, Daly City, and the broader Peninsula to find the right solution for their individual situation — budget, bone health, lifestyle, and all. You don’t have to figure it out alone.
The Bigger Lesson: Your Current Teeth Are Worth Protecting
Here’s the part of this story that doesn’t get as many headlines but might be the most important: the best tooth is always the one you already have. No implant, bridge, or future tooth-growing drug will ever be quite as good as a healthy natural tooth you kept. Consistent preventive dental care — cleanings, exams, catching small problems before they become big ones — is still the most powerful dental technology available, right now, today.
In our South San Francisco office, we see firsthand how a small cavity caught early versus caught late can mean the difference between a simple filling and a root canal or extraction. That gap is enormous. Every tooth you keep is one you’ll never need to replace — with a crown, an implant, or someday, maybe, a pill.
Frequently Asked Questions
Can humans actually grow a third set of teeth naturally?
In rare cases, people with a condition called hyperdontia do spontaneously grow extra permanent teeth. But for most people, the dormant third-dentition tooth buds never activate on their own. The new Japanese research is working to change that through a drug that blocks the protein suppressing those buds — though it is still in early clinical trials.
When will the tooth-growing drug be available to the public?
It’s genuinely hard to predict, but most experts suggest a best-case scenario of the mid-2030s — and even then, regulatory approval would likely be first for people with congenital tooth loss conditions. It’s an exciting development, but not an imminent one. If you have missing teeth now, modern options like dental implants, bridges, and dentures are excellent choices that shouldn’t be put off.
Does this research mean I should skip getting an implant and just wait?
We’d recommend against waiting. Missing teeth can cause bone loss, shifting teeth, bite problems, and other complications that develop over months and years. The tooth-growing research is promising, but it’s at least a decade away from being a realistic option for most people. Our dental team is happy to walk you through today’s best options at a consultation.
What can I do right now to protect the teeth I have?
The fundamentals are still the best tools we have: brush twice a day with a fluoride toothpaste, floss daily, and see your dentist for regular cleanings and exams. These habits — consistently practiced — dramatically reduce your risk of tooth loss. At Vaksman Dental Group, we also offer preventive treatments like dental sealants and personalized hygiene plans to help protect your smile for the long haul.
Ready to protect the smile you have — or explore options for teeth you’ve lost? Our team at Vaksman Dental Group in South San Francisco is here to help.
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Written by the Vaksman Dental Group team and medically reviewed by Dr. Irena Vaksman, DDS — South San Francisco.