Can Scientists Regrow Human Teeth? What the Research Really Shows

Short answer

• No. No dentist can regrow a lost adult tooth for you today, and no drug is approved anywhere for regrowing human teeth. The research behind the headlines is real and worth understanding, but it is still at an early stage. What has actually happened is narrower than most headlines suggest. In animal studies published in 2021, an antibody that blocks a protein called USAG-1 produced a whole extra tooth in mice, and the same approach worked in ferrets. In Japan, a first human study of a drug based on that antibody, called TRG035, has been completed as a safety study in healthy adult men. It was designed to test tolerability, not to prove that teeth grow in people. The developer, Toregem BioPharma, has reported that safety was confirmed, but detailed results have not been published, and no results are posted in the trial registry. Human regrowth, meaning a complete new tooth forming in the right place and working in the bite, has not been shown. A Phase IIa trial in 24 children born missing several permanent teeth is being prepared. In August 2026 the company announced that the regulator in Japan had completed its investigation of the trial notification, and that ethics review still had to happen before children could be enrolled and dosed. A date around 2030 is a developer target for possible availability in Japan if trials succeed. It is not an approval, not a promise, and not a date for other countries. If you are missing a tooth now, do not wait for this research. Talk to your dentist about the proven options that exist today, including implants, bridges and dentures, and about what happens if a gap is left untreated.

Why Adult Teeth Do Not Grow Back on Their Own

Most people grow two sets of teeth in a lifetime. The first set, often called baby teeth or primary teeth, comes through in early childhood. The second set, the permanent teeth, replaces them. After that, the body does not normally start the process again. If a permanent tooth is lost to decay, gum disease, injury or extraction, the space stays empty unless a dentist replaces it.

That limit is not a simple failure of healing. Tooth formation is a tightly timed developmental program. Cells receive signals in a particular order, tissues fold and shape themselves, enamel forms on the outside, dentin forms underneath it, and living pulp forms at the center. Once that program has run and the adult jaw has matured, the signals that started it are largely switched off. A broken bone can knit because bone keeps a repair system active through life. A whole tooth has no equivalent repair system. Very early enamel damage can sometimes be slowed with fluoride and saliva, but a lost tooth is not rebuilt in the way a cut closes.

People ask whether teeth grow back after the age of 18, after removal, after a cavity, or a third time. For a permanent tooth in an ordinary adult, the answer is no, not on its own. A baby tooth that falls out is replaced because its permanent successor was already developing underneath it. That is not regrowth of the same tooth. It is the planned arrival of the next set. A wisdom tooth that appears late is not a regrown tooth either. It is a permanent tooth erupting later than the others.

Some animals do keep replacing teeth through life. Sharks are the famous example. Humans do not share that system. The research question is therefore whether scientists can safely reactivate a dormant developmental pathway, or build a new tooth from cells, in a way that works in a human mouth.

The Japan Research in Plain Language

The protein that acts as a brake

The work that has drawn the most attention comes from a team led by Dr Katsu Takahashi, working with Kyoto University, the University of Fukui and the Medical Research Institute Kitano Hospital in Japan, and later through Toregem BioPharma, a Kyoto University spinout founded to develop the treatment.

The team studied a protein called USAG-1, short for uterine sensitization associated gene-1, made by the gene SOSTDC1. In simple terms, USAG-1 acts as a brake on tooth formation. It dampens two signaling systems that help decide how many teeth form, called BMP and Wnt signaling. In mice that lacked USAG-1, researchers observed extra teeth forming, including rudimentary teeth that would normally have disappeared surviving and erupting instead. That raised a clear question. If the brake could be eased in a controlled way, would a dormant tooth bud be able to develop?

A tooth bud is an early cluster of cells that has the potential to become a tooth. Humans are understood to carry a rudimentary third tooth bud, part of what researchers call a third dentition, that is normally suppressed very early in development and usually regresses. The Japanese approach does not try to assemble a tooth from unrelated parts. It tries to release the brake so that a bud that is already present can proceed. The drug developed for this purpose, TRG035, also written TRG-035, is a humanized monoclonal antibody designed to block USAG-1. In the human studies so far it has been given as a single intravenous dose, not as a pill and not as an injection into the gum.

What the animal studies actually showed

Animal work came first, and its details matter. In the key study, published in Science Advances on February 12, 2021, Murashima-Suginami and colleagues tested several monoclonal antibodies against USAG-1 in mice. Because USAG-1 interacts with both BMP and Wnt, several antibodies caused poor birth and survival rates in mice, a warning that interfering with both systems affects development well beyond teeth. One antibody disrupted only the interaction between USAG-1 and BMP, leaving the Wnt interaction intact. With that antibody, a single administration was enough to generate a whole tooth in mice, including in mouse models of congenital tooth agenesis, where teeth fail to develop at all. The team then confirmed the same benefit in ferrets.

Reports of that work describe teeth with enamel on the outside, dentin inside and pulp at the center, sitting alongside the other teeth. That suggests a whole tooth structure, not just a lump of mineral. Ferrets matter because, like humans, they have two sets of teeth, with dental patterns closer to ours than a mouse has.

It is still animal evidence. Animal jaws, tooth size, eruption timing and bite forces differ from human jaws, and a result in a mouse or a ferret does not prove the same result in a person. The animal work also answers a congenital question first, whether a tooth that never developed can be rescued, which is not the same as replacing a molar lost to decay in an adult.

What the first human study tested, and what it did not

Human testing began with safety, not with proof of regrowth. The first human study of TRG035 began at Kyoto University Hospital in late 2024. It is registered in the Japan Registry of Clinical Trials as jRCT2051240154, a Phase I single-administration study described as double-blind, randomized, placebo-controlled and dose-escalating. Participants were assigned by chance to one of five increasing dose levels or to a placebo, and neither participants nor researchers knew who received what, so safety could be judged without bias.

The target sample was 30 healthy adult men, each missing at least one molar. The registry lists tolerability as the primary outcome, with how the drug moves through the body and the frequency of antibodies against TRG035 itself as secondary measures. It was not designed to prove that teeth regrow in people, or to replace a specific missing tooth on demand.

The registry lists recruitment as complete, with no results posted. Toregem BioPharma has reported that Phase I was completed and safety was confirmed. That is a company report, not a published result. Detailed peer reviewed results are not publicly available, and effectiveness in humans is unproven until such results are published and independently examined.

Who the next study is for

The planned next step is a Phase IIa trial in children with severe congenital partial anodontia, meaning children born missing several permanent teeth, with a target of 24 children. On August 17, 2026, Toregem BioPharma announced that the Pharmaceuticals and Medical Devices Agency in Japan had completed its investigation of the clinical trial notification for that trial, and that review by the institutional review board at the trial site still had to happen before subjects could be enrolled and dosing could begin. Earlier reporting described the intended group as young children, roughly ages 2 to 7. Treat the exact ages as part of a plan still being finalized, not as a study already treating children.

That focus makes sense. Children born missing teeth have the clearest unmet need, because a tooth that never developed cannot be waited out, and the biology fits the drug, which aims to rescue a developmental process that stalled in a jaw still growing. A growing jaw differs from a mature adult jaw, so success in children, if it comes, would not automatically prove success in adults. Adult tooth loss from decay, gum disease or injury is a later, separate question that has not been tested in people.

Japan’s Ministry of Health, Labour and Welfare designated TRG035 as an orphan drug for severe congenital hypodontia in September 2025, according to the company. Orphan designation supports development for a rare condition. It is not an approval.

The Evidence at a Glance

What Regrowing a Tooth Could Mean, and What It Could Not

Even if this research succeeds, be precise about what kind of success it would be. A drug that triggers a new tooth would replace a missing tooth. It would not repair a cavity in an existing tooth, reverse gum disease, rebuild bone lost to long-standing infection, or undo years of wear. If you want to understand what actually treats a cavity today, see our guide to how cavities are treated and what your options are. A newly grown tooth would still be vulnerable to decay and gum disease, just like any natural tooth, so brushing, flossing, fluoride and regular dental checks would still matter.

Position matters as much as growth. A tooth that grows in the wrong place, at the wrong angle, or at the wrong size could disturb the bite, crowd neighboring teeth, or cause pain. Researchers must show that a triggered tooth erupts in a useful position, reaches a functional height, and works with the opposing teeth. A tooth that forms but never erupts is not a clinical success.

The number of teeth also matters. Growing one extra tooth in an animal is different from replacing several teeth in different parts of the mouth. Early clinical work is focused on congenital absence, a small number of missing teeth in children. Extending that to an adult who lost a molar to decay raises separate questions about jaw bone, gum health, space and bite, none of them answered in humans.

No food, vitamin, mouth rinse, chewing exercise or home method has been shown to make a permanent tooth grow back, or grow back faster. If a product promises to regrow a tooth at home, that promise is not supported by the human evidence described here. The credible research is happening in laboratories and regulated clinical trials, not in a bottle sold for home use.

Other Research Paths, and Why They Are Not the Same Thing

Tooth regrowth is an umbrella phrase covering several very different ideas. Lumping them together makes timelines confusing, because some are much closer to practical use than others, and some are not tooth regrowth at all.

The antibody path

This is the Japan approach described above, waking up a dormant bud inside the body by blocking USAG-1. It is the path furthest along in human testing, having completed a first safety study and preparing a first study in affected children. Furthest along still means early, and no effectiveness in people has been shown.

Lab-Grown Teeth and Tooth Organoids

A second path tries to build a tooth outside the body, or grow an early tooth structure that could one day be placed in the jaw. Work at King’s College London, with Imperial College London, is a clear example, often reported in language that sounds closer to patients than it is.

In a study published in ACS Macro Letters in 2024, Zhang and colleagues used defined hydrogels, jelly-like materials engineered to mimic the environment around developing cells, to grow tooth organoids in the laboratory. The cells were dental epithelial and mesenchymal cells taken from mouse embryos. In the right hydrogel, those cells could communicate and organize into early tooth like structures over days in a dish. That is laboratory, in vitro work with mouse cells. It is not a human tooth grown in a lab, it has not been placed in a human jaw, and it is not a treatment. Its value is showing more precisely what environment tooth cells need to start forming a tooth. The researchers describe two distant possibilities, growing a whole tooth in the lab for later implantation, or placing early-stage tooth cells into the jaw to continue developing there. Both remain research ideas.

Stem cell scaffolding and cell seeding

Related work places cells with the potential to become tooth tissues on a biodegradable scaffold shaped like a tooth, or studies cells from a developing or extracted tooth as a source for seeding a new tooth. This work is largely in animal models and laboratory studies, and it faces the challenge of getting the shape, the root, the nerve supply and the connection to the jaw bone right, reliably, in a living mouth.

Enamel repair

A fourth area is enamel repair. Synthetic peptides and other materials are being studied for helping to remineralize early enamel damage. This is not growing a whole tooth. It is strengthening the outer layer of an existing tooth. Some approaches may reach patients sooner than any whole tooth drug, but they do not replace a missing tooth or reverse a deep cavity.

Keeping these paths separate avoids a common misunderstanding. A headline about enamel repair does not mean a missing molar can be regrown, and a headline about a tooth in a mouse does not mean a dentist can offer the same treatment next month.

Why Humans Stop at Two Sets

Humans do not have a single gene that simply forbids a third set. Tooth number and timing are controlled by a network of signals that also affect other tissues, and USAG-1 is only one part of that network. That is one reason a drug that blocks USAG-1 must be tested so carefully. The 2021 animal study made the point directly, because antibodies that interfered with both BMP and Wnt caused poor birth and survival rates in mice, while the antibody that spared Wnt did not show that problem in the same way. A treatment for people must act in a targeted way without unwanted effects elsewhere, including on bone, where the same signals are active.

A rudimentary third bud also does not mean the body is ready to grow a third set on request. The bud is suppressed early, and the space, blood supply and bite environment in an adult jaw differ from those in a developing child. The research is interesting precisely because it tests whether that early suppression can be reversed in a controlled way, not because a third set is sitting ready to erupt. Adult use, if it ever happens, will need its own evidence.

How Close Are We, Honestly?

We are at the completed safety study stage for one approach, and at the laboratory or animal stage for the others. That is progress, and it is more than speculation, but a first human study is not the same as a proven treatment.

For the antibody approach, researchers must still publish full safety results, then show in a controlled trial that teeth actually form in people, in the intended positions, with a functional bite and without harm. They must show the effect is repeatable, the dose is right, and there are no important late effects. Regulators must review that evidence, and manufacturing, cost and long term follow up must be worked out. Each step takes time. A reported aim of around 2030 for Japan, if trials succeed, is an optimistic developer target for one country and one patient group first, not a global availability date.

For the other paths, the distance is greater. Stem cell, organoid and cell seeding approaches must first show reliable whole tooth formation in animals, then safety in people, then effectiveness in people. Enamel repair is closer in some forms, but it answers a different question.

What has not happened also matters. No regulatory agency has approved a tooth regrowth drug for routine dental use, no dentist can prescribe one as a standard treatment, and no clinical guideline recommends waiting for regrowth instead of treating a missing tooth now. If a clinic advertises tooth regrowth treatment for patients today, ask for the regulatory approval and the published human evidence behind it.

What to Do If You Are Missing a Tooth Now

Waiting for research is not a treatment plan. A missing tooth can affect chewing, speech, the position of neighboring teeth and the bone in the jaw. Neighboring teeth can drift into the gap, the opposing tooth can over erupt, and bone in the empty socket can shrink over time, making later replacement more complex. Talk to your dentist about current options, and ask them to assess the gap, the gum, the bone and the bite.

Dental implants are the most widely used long term replacement for a single missing tooth in suitable patients. An implant is a titanium post placed in the jaw bone, topped with a crown that looks and functions like a tooth. Implants require enough bone, healthy gums and good general health for healing, and they are not suitable for everyone. Bridges use neighboring teeth to support a replacement tooth, and dentures replace several teeth or a full arch with a removable appliance. Each option has trade-offs in cost, maintenance, longevity and effect on neighboring teeth. They are proven treatments in their own right, not placeholders.

Not every dental problem is a missing tooth, and regrowth research does not help with those either. A damaged tooth that is still present is repaired, not regrown, which is why it helps to understand how chipped teeth are fixed with the methods dentists use today. Cosmetic treatments work on teeth that are already there too. Options such as prepless veneers change the appearance of an existing tooth without drilling it down. They do not create a new tooth, and they are not an alternative for a gap.

If cost or timing is a concern, raise it directly with your dentist, and ask what delaying might mean. Do not delay urgent care because of a future promise. Pain, swelling, infection or a broken tooth needs prompt assessment.

For children born missing teeth, parents should seek advice from a pediatric dentist and, where appropriate, a specialist in congenital dental conditions. Early planning can protect space, speech, chewing and confidence, and keep future options open. An experimental trial is not a substitute for that planning, and participation, if ever offered, should be discussed with the treating team with full information about risks, unknowns and alternatives.

How to Read the Next Headline

Tooth regrowth stories will keep appearing, and many will overstate the evidence. A few checks help to separate a real advance from hype.

First, ask whether the result is in animals, in cells in a dish, or in people. Animal and laboratory results are valuable, but they are not human proof. Second, ask whether a human trial was designed to test safety or to test whether teeth actually grow. A safety study that finishes is good news, but it does not prove effectiveness. Third, ask whether full results have been published in a peer reviewed journal, or whether the claim rests on a press release or a company announcement, which is not a substitute for published data other scientists can examine. Fourth, ask what the researchers themselves say about timeline and scope. A team that says it hopes to help children born missing teeth first is making a narrower, more credible claim than a headline promising new teeth for everyone. Fifth, watch for language that promises a cure, a fixed date, or a home method. Credible research language is cautious, because the unknowns are still large.

Also notice what a headline leaves out. Does it mention position, bite and long term follow up, that a new tooth would still need care, or that a treatment, if approved, would initially be for a specific group? If so, it is probably simplifying less.

Frequently Asked Questions

Can adult teeth grow back?

No, not on their own. Once a permanent tooth is lost, the body does not grow a replacement. Baby teeth are replaced by permanent teeth already developing underneath them, which is different.

Can humans grow a third set of teeth?

Humans carry a rudimentary third tooth bud that is normally suppressed during development. Researchers are testing whether blocking USAG-1 can reactivate such a bud, but no human regrowth has been demonstrated in published results.

Is there a pill or drug that regrows teeth now?

No drug is approved for routine clinical use to regrow teeth in people. TRG035 is given by intravenous infusion in research, not as a pill, and it has only completed a first safety study in Japan. It is not available as a standard dental treatment.

How long does it take to grow a tooth?

In normal development, a permanent tooth takes years to form and erupt. There is no established human timeline for a regrown tooth, because human effectiveness has not been shown.

Will tooth regrowth replace implants?

Not in any foreseeable plan, and not on current evidence. Even if regrowth succeeds for specific groups, starting with children born missing teeth, implants, bridges and dentures will remain important for many patients and patterns of tooth loss. Talk to your dentist about current options rather than waiting.

Can I make my teeth grow back naturally?

No home method, food, supplement, rinse or chewing routine has been shown to regrow a lost permanent tooth. Good oral care protects the teeth you still have, but it does not create a new tooth.

What should I do if I lose a tooth?

See a dentist promptly. Ask about the cause, the state of the gum and bone, and the replacement options that fit your health, bite and budget. Do not wait for an unproven future treatment while a gap causes teeth to shift or bone to shrink.

Sources & references

• Murashima-Suginami, A. et al. Anti USAG-1 therapy for tooth regeneration through enhanced BMP signaling. Science Advances, 2021, 7(7), eabf1798. https://doi.org/10.1126/sciadv.abf1798
• Kyoto University. New drug to regenerate lost teeth. Research news, March 31, 2021, summarizing the Science Advances study, the single administration whole tooth result in mice, and the confirmation in ferrets. https://www.kyoto-u.ac.jp/en/research-news/2021-03-31?wpmobileexternal=true
• Ravi, V. et al. Advances in tooth agenesis and tooth regeneration. Regenerative Therapy, 2023, 22, 160 to 168. DOI 10.1016/j.reth.2023.01.004. Review of USAG-1, the rudimentary third dentition, and congenital tooth agenesis.
• Toregem BioPharma Co., Ltd. Announcement for Completion of the PMDA Investigation of CTN for TRG035 Phase IIa Trial. August 17, 2026. Phase IIa in pediatric patients with severe congenital partial anodontia, target 24 subjects, institutional review board review still required before enrollment and dosing, and orphan designation noted. https://toregem.co.jp/en/english2025/wp-content/uploads/2026/08/Toregem_Compleatuion-of-the-PMDA-Investigation-of-CTN-TRG035-P2-.pdf
• Dentistry.co.uk. Tooth regrowth drug trial planned for 24 children in Japan. August 18, 2026. Reporting that Toregem said Phase I confirmed the drug's safety although detailed results have not been made publicly available, and that the planned Phase IIa would move testing from healthy adults into patients. https://dentistry.co.uk/2026/08/18/tooth-regrowth-drug-trial-planned-for-24-children-in-japan/
• Zhang, X. et al. Generating Tooth Organoids Using Defined Bioorthogonally Cross-Linked Hydrogels. ACS Macro Letters, 2024, 13, 1620 to 1626. DOI 10.1021/acsmacrolett.4c00520. King's College London and Imperial College London work growing tooth organoids in vitro from mouse embryonic dental cells. https://spiral.imperial.ac.uk/server/api/core/bitstreams/bea21199-469e-46eb-bcc0-ef73a2c8a38b/content
• Japan Registry of Clinical Trials, record jRCT2051240154. Phase I Single-Administration Study of TRG035 in Healthy Adults, a double-blind, randomized, placebo-controlled, dose escalation study at Kyoto University Hospital, sponsor Toregem BioPharma, target 30 participants, tolerability as the primary outcome, recruitment listed as complete, no results posted in the registry record as reviewed for this article.