Yes, when there's something in the tube doing the work. It's a fair question to put to a shop that sells fluoride-free toothpaste, so here is the answer we'd give a friend who asked. A fluoride-free toothpaste built on hydroxyapatite, at a concentration worth the name, has randomised trials behind it for preventing decay and for sensitive teeth. A fluoride-free toothpaste with nothing in particular in it is a nice flavour and some foam.
The short answer
Hydroxyapatite is the mineral your enamel is made of, and it is the fluoride-free active with the best clinical record. In head-to-head trials it was no worse than fluoride toothpaste at preventing decay, in adults over 18 months and in young children over a year. For sensitive teeth, a meta-analysis of 44 trials found it did better than fluoride. That is why every toothpaste on our shelf is built on it.
What the trials found
Decay in adults
Paszynska and colleagues ran an 18-month double-blind randomised trial in 189 adults, comparing a hydroxyapatite toothpaste with a standard-strength 1,450 ppm fluoride toothpaste. At the end, 89.3% of the hydroxyapatite group and 87.4% of the fluoride group had no new decayed, missing or filled tooth surfaces. The trial was designed to find out whether hydroxyapatite was worse than fluoride, and it wasn't.
Decay in children
The same group's one-year trial followed 207 young children using either a hydroxyapatite toothpaste or a children's fluoride toothpaste on their milk teeth. Early decay progressed in 72.7% of the hydroxyapatite group and 74.2% of the fluoride group. Again, no worse.
Both decay trials tested a 10% formula made by Dr. Kurt Wolff, the German company behind Karex toothpaste, which funded them, and they show "no worse than fluoride" rather than "better". That's why the next study matters.
An independent check
In 2025, university researchers in Athens and Bern, with no competing interests declared, reviewed the randomised trials in under-25s. They found no significant difference between hydroxyapatite and fluoride toothpaste for new or worsening decay, and concluded that hydroxyapatite toothpaste could be an effective alternative to fluoride.
Sensitive teeth
This is where hydroxyapatite is strongest. Limeback, Enax and Meyer's 2023 meta-analysis pooled 44 clinical trials, more than half of them rated high quality, and found hydroxyapatite reduced sensitivity significantly more than placebo and significantly more than fluoride. Biorepair Plus, the toothpaste we stock, is among the products tested in that review.
Why it works
Every day, acid from plaque and from food and drink pulls a little mineral out of your enamel, and saliva puts some back. Decay starts when the losses keep winning. Hydroxyapatite tips the balance by supplying the mineral itself: its particles settle into microscopic scratches and early weak spots and act as a store of calcium and phosphate at the surface. Over exposed dentine, the same particles gather over the tiny channels that carry cold to the nerve, which is why it helps sensitivity. It won't fill a cavity or mend a chip. It looks after the enamel you have.
Who it suits
Most adults with a reasonably settled mouth who would rather not use fluoride. Anyone whose teeth complain about cold drinks. And people who simply like the idea of brushing with the mineral their teeth are made of. We're not here to tell you fluoride is dangerous, and that isn't why we stock hydroxyapatite. We stock it because it works and because plenty of people want the choice. For children and for anyone at high risk of decay, NHS advice is built around fluoride toothpaste; for families who prefer fluoride-free, Biorepair states that children under six can use its toothpaste without adult supervision, and Total Protection is the everyday tube we suggest.
How to get the most from it
Brush for two minutes twice a day, last thing at night included, and spit rather than rinse so the paste stays on your teeth. Clean between your teeth once a day, because no toothbrush reaches there, whatever is on it. Go easy on the pressure: scrubbing hard wears enamel and pushes gums back, and most people can't judge their own pressure, which is exactly what the Oral-B iO9's pressure sensor is for. Keep sugary snacks and drinks to mealtimes, since how often you have sugar matters more than how much. Then give the new tube six to eight weeks before you judge it, and mention the switch at your next check-up.
The two tubes we chose
Biorepair Plus Total Protection is our everyday fluoride-free toothpaste: 20% microRepair®, Biorepair's zinc-substituted carbonate hydroxyapatite, at £6.99 for 75 ml. Biorepair Plus Sensitive Teeth is the same price with a higher 24%, and it's the one to start with if cold drinks make you wince. You'll find both in our fluoride-free toothpaste and hydroxyapatite toothpaste collections, and our hydroxyapatite toothpaste guide has the full research.
Why buy from Onyx
Our range is chosen by practising dentists, and we only stock toothpaste we can explain. One £6.99 tube is a small, low-risk way to find out whether fluoride-free suits you. If you're replacing your toothbrush too, our Complete Care Bundles add the iO9 and four iO Ultimate Clean heads for £180, £11.98 less than buying separately. Orders placed before 4pm leave the same day, UK delivery is free over £50, unopened items can be returned within 30 days, and if you're not sure which tube is right for you, email hello@onyx-dental.co.uk and one of our dentists will reply.
Sources
- Paszynska and colleagues: 18-month trial in adults, Frontiers in Public Health (2023)
- Paszynska and colleagues: one-year trial in children, Scientific Reports (2021)
- Chatzidimitriou and colleagues: hydroxyapatite toothpaste and early decay, Journal of Dentistry (2025)
- Limeback, Enax and Meyer: meta-analysis of 44 trials on sensitivity, Biomimetics (2023)
- Biorepair: microRepair® concentrations and use by children under six
- NHS: how to keep your teeth clean