- I stopped recommending nano-hydroxyapatite after going back to the chemistry of remineralization.
- It's a great desensitizer. Giving your teeth calcium isn't its strength.
- No brand has published third-party stability testing for its nanoparticles.
- Some trials found it kept pace with fluoride, and several involved a manufacturer's scientists.
- I'd skip tubes that mix fluoride and nano-hydroxyapatite first.
- For kids, fluoride still has the strongest evidence.
- My concern is whether it works, and whether your tube matches what was tested.
I don't recommend any hydroxyapatite toothpaste right now. Hydroxyapatite is a very stable crystal, so it releases very little calcium, and no brand has published third-party stability testing for its nanoparticles. It does help with sensitivity. For cavity protection, I recommend fluoride.
My Verdict at a Glance
I match the toothpaste to your goal, and fluoride covers the goal most people have.
| Your goal | What I recommend | Where nano-hydroxyapatite fits |
|---|---|---|
| Prevent cavities | Fluoride toothpaste, and a prescription 5,000 ppm paste if you're cavity-prone | Not my pick |
| Sensitive teeth | A potassium nitrate or stannous fluoride paste, like Sensodyne Pronamel | It helps, and it's a great desensitizer |
| Fluoride-free, low cavity risk | Elementa tooth gel | Not my pick until stability data exists |
| Kids | Fluoride toothpaste in the right amount for their age | Not my pick for a high-risk group |
| Already using nano-HA | Keep your checkups, and switch to fluoride if new cavities appear | Skip any tube that adds fluoride |
Why I Changed My Mind
I was on the nano-hydroxyapatite train early, and I stopped recommending it. I learned more of the science. A lot of us were hoping that it worked.
There is some science to it where it feels like it makes sense. When you look at the mechanism, though, it doesn't do what it's marketed for. I feel like it's a lot of a marketing grab.
So I went back to the chemistry of remineralization and took a course to get a deep refresher. My conclusion is that the science isn't there to recommend it. There are no sides, there's science.
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I get reached out to all the time by nano-hydroxyapatite brands. I haven't partnered with them, because I didn't know whether they work.
The Calcium Problem
Nano-hydroxyapatite is marketed as a way to put calcium back into your teeth, and it releases very little. Hydroxyapatite is a very stable crystal, so it doesn't dissolve easily to release calcium for remineralization.
In one lab test, hydroxyapatite sat in water and released only about 7.6 ppm of dissolved calcium. US tap water averaged around 50 ppm in one survey. A saturated hydroxyapatite solution has less free calcium than almost any unfiltered tap water.
That doesn't make it useless. It's a great desensitizer. "It remineralizes by giving you calcium" just isn't its strength.
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The Stability Problem
Nanoparticles only work as designed if they stay nano-sized inside the tube. Particles this small tend to clump together over time, and clumped particles behave like bigger ones.
Once one of these companies does third-party stability testing, which should be required for nanoparticles, we can talk. To my knowledge, no major brand has published it.
Even the safety review that cleared nano-hydroxyapatite in Europe only applies to particles of a specific shape and size. You can't tell from a label whether your tube still matches that description.
Nano vs Micro Hydroxyapatite
Nano and micro hydroxyapatite are different ingredients, and many labels don't tell you which one you're getting. Nano particles are measured in billionths of a meter, while micro particles are roughly a thousand times larger.
Microparticles sit on the surface and can plug the tiny tubes in exposed dentin, which is why they help with sensitivity. Several of the best-known clinical trials tested micro-sized hydroxyapatite, not the nano version on most labels.
Some brands blend both and list one combined percentage. A tube that says "15% hydroxyapatite" may be mostly micro particles, so the number tells you less than it seems.
What the Research Shows
The research on hydroxyapatite toothpaste is promising in places and thin overall. It's also much younger than the research on fluoride.
- Cavities: in adults, a hydroxyapatite paste kept up with fluoride toothpaste over 18 months. A review of four trials in young people also found no clear difference.
- Who ran the studies: several trials and reviews include scientists employed by a company that sells hydroxyapatite toothpaste. Most were small or short.
- Fluoride's track record: fluoride toothpaste prevents about a quarter of new cavities, across decades of trials.
- Sensitivity: nano-hydroxyapatite eased sensitivity more than other treatments in short trials. This is where it does best.
In the US, the FDA's list of approved anticavity ingredients for toothpaste includes only forms of fluoride. Hydroxyapatite toothpastes sold in the US don't carry an approved cavity-prevention claim.
Why I Skip Fluoride and Nano-HA Combos
Tubes that combine fluoride and nano-hydroxyapatite are the first ones I'd skip. Having both in one formula makes it worse than either one alone.
If you want fluoride, use a fluoride toothpaste, and if you want to try hydroxyapatite, keep it separate.
Hydroxyapatite Toothpaste for Kids
Kids are one of the highest-risk groups for cavities, so this is the last place I'd experiment. Fluoride's evidence in children spans decades of trials.
I'm okay if people aren't using fluoride and their kids don't have cavities. If they have cavities, I'm like, why don't you use it?
Everything that we put in our kids' mouths should be third-party tested. People think I'm crazy, but I think that should be the standard. The best toothpaste for kids pairs the right fluoride amount with a flavor they'll accept.
Is Hydroxyapatite Safe?
Europe's consumer safety committee considers nano-hydroxyapatite safe in toothpaste up to 29.5%, for rod-shaped, uncoated particles of a specific size. Its 2025 safety opinion doesn't cover needle-shaped particles.
My concern isn't that it's dangerous. It's whether it does what the marketing says, and whether the particles in your tube are the ones that were tested.
What I Recommend Instead
- For cavity protection: a fluoride toothpaste. My everyday tube is Sensodyne Pronamel Gentle Whitening, and I ask cavity-prone patients about a prescription 5,000 ppm paste.
- For sensitivity: potassium nitrate or stannous fluoride. The best toothpaste for sensitive teeth depends on which one fits you, and stannous fluoride vs sodium fluoride is the main choice.
- For a fluoride-free option: Elementa tooth gel, with nano silver, calcium and xylitol, and no hydroxyapatite. I have a discount code with Elementa: JOYCE20 takes 20% off.
- For extra remineralization support: Elementa's rinse first, then your fluoride toothpaste. It helps the fluoride penetrate the biofilm.
- At your cleaning: fluoride varnish, right after the biofilm has been removed.
Elementa is the top product I use for myself. It's fluoride-free, so it could be a standalone product, but I pair it with fluoride. The best remineralizing toothpaste for you depends on your cavity risk.
If You're Set on Hydroxyapatite
Read the label before you buy, and let your checkups tell you if it's working.
- Nano or micro: does the label say which, and give the ratio?
- Fluoride added: if yes, put it back.
- Stability testing: has the brand published third-party data on particle size over shelf life?
- Heavy-metal testing: has it published third-party results?
- Your next checkup: if new cavities show up, switch to fluoride.
What If Scenarios
What If I've Used Nano-HA for Years With No Cavities?
If you're cavity-free without fluoride, I'm fine with that. Keep your regular checkups so your dentist can catch a change early.
What If I Got a Cavity While Using It?
Switch to a fluoride toothpaste and ask about fluoride varnish at your cleanings. A new cavity means your current routine isn't enough for your risk.
What If I Bought It for Sensitive Teeth?
That's the job it does best. If sensitivity is your only issue and you get no cavities, it's a reasonable choice, and potassium nitrate pastes are another option.
What If My Child's Dentist Suggested It?
Ask what your child's cavity risk is. For a child who gets cavities, fluoride in the right amount for their age has the strongest evidence.
What If I Have Dry Mouth?
Dry mouth raises your cavity risk, and this isn't the place to experiment. Fluoride works.
What to Do Next
If you're using nano-hydroxyapatite and getting cavities, switch to fluoride. If you're cavity-free and happy, keep your checkups so your dentist can confirm it's working.
Sources
- Paszynska E, Pawinska M, Enax J, Meyer F, Schulze zur Wiesche E, May TW, et al. Caries-preventing effect of a hydroxyapatite-toothpaste in adults: a 18-month double-blinded randomized clinical trial. Frontiers in Public Health, 2023;11:1199728: https://pubmed.ncbi.nlm.nih.gov/37533523/
- Chatzidimitriou K, Theodorou K, Seremidi K, Kloukos D, Gizani S, Papaioannou W. The role of hydroxyapatite-based, fluoride-free toothpastes on the prevention and the remineralization of initial caries lesions: a systematic review and meta-analysis. Journal of Dentistry, 2025;156:105691: https://pubmed.ncbi.nlm.nih.gov/40107597/
- Pawinska M, Paszynska E, Amaechi BT, Meyer F, Enax J, Limeback H. Clinical evidence of caries prevention by hydroxyapatite: an updated systematic review and meta-analysis. Journal of Dentistry, 2024;151:105429: https://pubmed.ncbi.nlm.nih.gov/39471896/
- Paszynska E, Pawinska M, Gawriolek M, et al. Impact of a toothpaste with microcrystalline hydroxyapatite on the occurrence of early childhood caries: a 1-year randomized clinical trial. Scientific Reports, 2021: https://pubmed.ncbi.nlm.nih.gov/33514787/
- Schlagenhauf U, Kunzelmann KH, Hannig C, et al. Impact of a non-fluoridated microcrystalline hydroxyapatite dentifrice on enamel caries progression in highly caries-susceptible orthodontic patients: a randomized, controlled 6-month trial. Journal of Investigative and Clinical Dentistry, 2019: https://pubmed.ncbi.nlm.nih.gov/30701704/
- de Melo Alencar C, de Paula BLF, Guanipa Ortiz MI, Baraúna Magno M, Martins Silva C, Cople Maia L. Clinical efficacy of nano-hydroxyapatite in dentin hypersensitivity: a systematic review and meta-analysis. Journal of Dentistry, 2019;82:11-21: https://pubmed.ncbi.nlm.nih.gov/30611773/
- Marinho VC, Higgins JP, Sheiham A, Logan S. Fluoride toothpastes for preventing dental caries in children and adolescents. Cochrane Database of Systematic Reviews, 2003: https://pubmed.ncbi.nlm.nih.gov/12535435/
- Scientific Committee on Consumer Safety. Scientific Opinion on Hydroxyapatite (nano), Submission IV, SCCS/1677/25, 26 June 2025: https://health.ec.europa.eu/publications/sccs-scientific-opinion-hydroxyapatite-nano-submission-iv_en
- US Code of Federal Regulations, 21 CFR 355.10, Anticaries active ingredients: https://www.ecfr.gov/current/title-21/chapter-I/subchapter-D/part-355/subpart-B/section-355.10
- Elementa Silver, Toothpaste Gel: https://elementasilver.com/products/tooth-gel
FAQ
Why Don't Dentists Recommend Hydroxyapatite?
Many dentists don't recommend hydroxyapatite because the evidence for cavity prevention is younger and thinner than fluoride's. It also releases very little calcium, and no brand has published third-party stability testing for its nanoparticles.
Does Hydroxyapatite Really Rebuild Enamel?
Hydroxyapatite doesn't rebuild enamel the way it's marketed. It's a very stable crystal that releases little calcium, though it can help with sensitivity by covering exposed dentin.
What Is the Downside of Using Hydroxyapatite Toothpaste?
The main downside is relying on it for cavity protection when fluoride has far stronger evidence. You also can't tell from the label whether the nanoparticles are still the size they were designed to be.
Which Toothpaste Contains the Most Hydroxyapatite?
A higher hydroxyapatite percentage doesn't mean a better toothpaste. The mix of nano and micro particles, and whether they stay stable, matters more than the number on the label.
Is Hydroxyapatite Better Than Fluoride?
Hydroxyapatite isn't better than fluoride for preventing cavities. A few trials found it kept pace, but fluoride has decades of evidence and is the only anticavity ingredient the FDA recognizes.
Is Nano-Hydroxyapatite Safe?
Nano-hydroxyapatite is considered safe in toothpaste by Europe's consumer safety committee, for particles of a specific shape and size. My concern is whether it works as marketed, not its safety.
Is Hydroxyapatite Toothpaste Good for Sensitive Teeth?
Hydroxyapatite toothpaste is good for sensitive teeth. Short trials found it eased sensitivity, and it's a great desensitizer.
Can Kids Use Hydroxyapatite Toothpaste?
Kids can use hydroxyapatite toothpaste, but it isn't my pick for them. Children are a high-risk group for cavities, and fluoride has the strongest evidence for protecting their teeth.
Dr. Joyce Kahng is a cosmetic dentist, veneer expert, and the founder of Orange + Magnolia Dental Studio in Costa Mesa, CA. With 16+ years in practice and a following of 1.5M+ across Instagram, TikTok, and YouTube, she's known for making dentistry actually make sense. She's been featured in Forbes, Vogue, Allure, Glamour and GQ, and is the creator of the VeneerLIFT™.
Our editorial process · written by Dr. Kahng, corrected in the open.
- 28 Oct 2026 Updated and rewritten by Dr. Kahng: why she stopped recommending hydroxyapatite toothpaste and what she recommends instead.
- 29 Apr 2026 Published. Clinical review by Dr. Joyce Kahng, DDS.
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