A note on where we stand. Minvelle is a nano-hydroxyapatite chewing gum for between brushings: one piece a day, chewed for at least 20 minutes, with 5.7 mg of nano-hydroxyapatite per 1.9 g piece printed on the box. It is not a toothpaste and it does not replace one. Whatever paste you choose from this guide stays your brushing base, and the gum, if you want it, is an extra step.

At a glance

Seven actives, one table

Swipe sideways on mobile. Label figures from FDA DailyMed drug labels and brand pages, nano-hydroxyapatite and bioactive glass figures from our own brand reviews, all checked 25 to 26 September 2026. Evidence citations are in Part 5. OTC = over the counter, Rx = prescription.

Part 1

What can remineralization do, and what can it not?

Before comparing tubes, it helps to know what the word promises. The US National Institute of Dental and Craniofacial Research (NIDCR) describes it on its tooth decay page: "A white spot may appear where minerals have been lost. This is a sign of early decay. Tooth decay can be stopped or reversed at this point. Enamel can repair itself by using minerals from saliva and fluoride from toothpaste." The next sentence is the one most labels leave out: "If more minerals are lost than can be restored, the enamel weakens and eventually breaks down, forming a cavity."

Cariologists describe the same thing as a daily tug of war. In a widely cited review, Featherstone (2008, PMID 18782377) calls caries "a continuum resulting from many cycles of demineralization and remineralization." Acids from plaque bacteria dissolve mineral from the crystals inside enamel. Saliva, fluoride and calcium and phosphate sources push mineral back in. Demineralization, he writes, "can continue unless halted with the end-point being cavitation." Cavitation is the one-way step: the surface collapses into a hole.

So every product in this guide works on the early side of that line. A remineralizing toothpaste can help an early, non-cavitated lesion, the white spot, take up mineral again and stop progressing. It cannot rebuild a tooth that already has a hole, and it cannot regrow enamel that has worn away. When a label says "repairs enamel", the honest reading is "remineralizes early surface and subsurface lesions". Our sibling guide on what 'enamel repair' labels contain goes through that wording product by product.

What that means in practice

• A white spot is the window. If your dentist points to an early white-spot lesion, a remineralizing routine is exactly what the evidence supports. Our guide to white spots on teeth explains the different causes, because not every white mark is early decay.
• A hole is not. If there is a cavity, the dentist fills it. No toothpaste, cream, mouthwash or gum changes that.
• It takes weeks, not days. Remineralization is gradual. Our tooth remineralization timeline sets out what the studies measured and over what periods.
• Erosion is a different problem. Acid from food and drink wears the enamel surface away. That is not the same as a caries lesion, and most of the evidence in this guide is about caries. Our comparison of cavities and enamel erosion covers the difference.

One more point that shapes the whole guide: in the US, the only anticavity wording the FDA allows on an over-the-counter toothpaste label is "Aids in the prevention of dental cavities" (or decay, or caries), under 21 CFR 355.50. "Remineralizes", "repairs enamel" and "reverses decay" are not on that list. When you see those words on a tube, they are marketing language, not an FDA-reviewed claim. That does not make them false. It means you should look for the active and its concentration instead of the adjective on the front.

Part 2

Which one should you buy? Picks by need

Here is the short version, by situation. The reasoning and the evidence for each pick follow in Parts 3 to 5. In every case, your dentist knows your caries risk and your teeth, and a dentist's advice beats a buying guide.

Everyday adult with healthy teeth: standard fluoride

Pick a sodium fluoride or stannous fluoride toothpaste in the normal over-the-counter range. This is the choice with the most evidence behind it by a wide margin. The 2019 Cochrane review found "high- and moderate-certainty evidence that 1000 to 1250 ppm or 1450 to 1500 ppm fluoride toothpaste reduces caries increments when compared with non-fluoride toothpaste", and that 1,450 to 1,500 ppm "slightly reduces" caries compared with 1,000 to 1,250 ppm. A basic paste like Crest Cavity Protection does the job. If you also want an antigingivitis and antisensitivity claim on the same label, a stannous fluoride paste like Colgate Total SF carries all three from one active. Our comparison of stannous and sodium fluoride goes deeper on that choice.

High caries risk or root caries: ask for 5,000 ppm

If you get new cavities regularly, have exposed roots, have dry mouth or are older with active root lesions, the strongest evidence points to prescription 5,000 ppm sodium fluoride toothpaste such as PreviDent 5000 Plus or Clinpro 5000. A 2026 network meta-analysis (Chen and colleagues, PMID 41720286) concluded that prescription high-fluoride toothpaste "can be considered as the first-line non-invasive therapy for arresting active root caries." For people who cannot tolerate or do not want the prescription, the same review said over-the-counter pastes with fluoride plus arginine, or bioactive ingredients, "could potentially be an optimum option." This is a conversation to have with a dentist, who writes the prescription anyway.

You prefer fluoride-free: nano-hydroxyapatite with a stated percentage

If you have decided, ideally with your dentist, to brush without fluoride, nano-hydroxyapatite is the fluoride-free active with the most human trial data. Choose a brand that states its percentage on the pack or product page, like Lumineux (10%) or Fygg (3.1% final concentration). Be clear about what you are choosing: the evidence shows hydroxyapatite was not inferior to fluoride in the trials run so far, not that it beats fluoride. Our ranking of hydroxyapatite toothpastes compares 13 brands on what they disclose, and our fluoride-free toothpaste guide covers the wider fluoride-free shelf.

Children who still swallow toothpaste: ask about the fluoride amount

Young children swallow some toothpaste, and that is why fluoride dosing in children is handled carefully. The FDA's required warning on every fluoride toothpaste reads: "Keep out of reach of children under 6 years of age. If more than used for brushing is accidentally swallowed, get medical help or contact a Poison Control Center right away." The Cochrane review adds that "the choice of fluoride toothpaste concentration for young children should be balanced against the risk of fluorosis." Prescription 5,000 ppm pastes are not for young children: PreviDent's label says not to use it under age 6 unless a dentist or physician recommends it.

That does not mean fluoride is wrong for children. Fluoride toothpaste is what most dentists recommend for children too, in an age-appropriate amount. Some parents prefer a fluoride-free paste while a child is still swallowing, and there is one trial on that choice: a 1-year randomized trial in 207 children (Paszynska and colleagues, 2021, PMID 33514787) found caries progression in primary teeth in 72.7% of the hydroxyapatite group and 74.2% of the fluoride group, which met its test for non-inferiority. It is a single trial from one research group. The right fluoride amount for your child is a question for your dentist or pediatrician.

Acid erosion: start from fluoride, and talk to your dentist

Erosion, the smooth wearing-away of enamel by acidic food and drink, is where this guide has to be most modest. The trials and reviews we cite measured caries lesions, not erosion. We found no study in our evidence set that tested any of these seven families specifically against erosion, so we do not rank one of them as the erosion pick. A fluoride toothpaste as your base, fewer acid exposures and advice from your dentist is the sound starting point. BioMin says its glass forms fluorapatite, which "dissolves at a pH of <4.0, HAP at a pH of 5.0, so is much more acid resistant". That is the brand's own claim, and BioMin F is out of stock right now.

Part 3

The fluoride families: sodium, stannous, 5,000 ppm

Three of the seven families are fluoride. They share one mechanism. Fluoride at the tooth surface helps enamel take mineral back up, the process NIDCR describes in Part 1. They differ in the fluoride compound, the concentration and the extra claims the label is allowed to make.

1. Sodium fluoride, standard strength

Example: Crest Cavity Protection Regular (Procter & Gamble). The FDA Drug Facts label on DailyMed, checked 26 September 2026, reads: "Active ingredient: Sodium fluoride 0.243% (0.15% w/v fluoride ion)." Purpose: "Anticavity toothpaste." Use: "helps protect teeth and roots against cavities." The inactive ingredients are sorbitol, water, hydrated silica, sodium lauryl sulfate, trisodium phosphate, flavor, cellulose gum, sodium phosphate, carbomer, sodium saccharin, titanium dioxide and blue 1. DailyMed classifies it as an over-the-counter drug label.

This is the plain baseline. It sits inside the FDA's over-the-counter rule for sodium fluoride pastes, and it is the kind of product the Cochrane review has the deepest evidence for. There is nothing special on the front of the tube, and for most adults it does not need to be special. The label's root-protection claim is worth one caveat: for older adults with active root caries, a 2025 analysis found 1,450 ppm gave much more variable results than 5,000 ppm (Part 5). For healthy teeth, standard strength is the evidence-based default.

2. Stannous fluoride

Example: Colgate Total SF, Active Prevention Clean Mint (Colgate-Palmolive). The FDA label reads: "Active ingredient: Stannous Fluoride 0.454% (0.15% w/v fluoride ion)." Purposes: "Anticavity, Antigingivitis, Antisensitivity." Potassium nitrate appears on this label only as an inactive ingredient, so all three claims rest on stannous fluoride itself. DailyMed classifies it as over the counter.

Stannous fluoride is the only over-the-counter active in this guide that carries anticavity, antigingivitis and antisensitivity claims on the FDA label from one ingredient. The FDA rule allows it at 0.351% to 0.474%, and 0.454% sits inside that range. There is no higher stannous tier, over the counter or on prescription: the monograph has no stronger stannous fluoride level at all. A general point from the dental literature, not specific to this product: stannous fluoride has historically been linked with surface staining, and modern stabilized formulas aim to reduce that. If you have had staining with a stannous paste before, mention it to your hygienist.

3. High fluoride, 5,000 ppm (prescription)

Example A: PreviDent 5000 Plus (Colgate Oral Pharmaceuticals). The FDA label reads: "Active Ingredient: Sodium Fluoride 1.1% (w/w)." It describes itself as a "self-topical neutral fluoride dentifrice containing 1.1% (w/w) sodium fluoride for use as a dental caries preventive in adults and pediatric patients", and in the same text calls itself "this prescription dental cream". Contraindication: "Do not use in pediatric patients under age 6 years unless recommended by a dentist or physician." It comes in 51 g tubes, in spearmint and fruitastic flavours. DailyMed classifies it as a prescription drug label.

Example B: Clinpro 5000 Anti-Cavity Toothpaste (3M ESPE, now Solventum). The FDA label calls it "3M ESPE Clinpro 5000 1.1% Sodium Fluoride Anti-Cavity Toothpaste" and states: "Each gram contains 5 mg of fluoride ion in a neutral pH base." Five milligrams per gram is 5,000 ppm. The label indicates it "for use as part of a professional program for the prevention and control of dental caries." Also a prescription label.

One detail for careful label readers. Solventum markets Clinpro 5000 around "fTCP", functionalized tricalcium phosphate. The FDA label's ingredient list names "tri-calcium phosphate" as an inactive ingredient and does not use the words "functionalized" or "fTCP". That is the brand's marketing name for an ingredient the label lists more plainly, not a difference in what is in the tube. Between the two products, the fluoride chemistry is the same: 1.1% sodium fluoride. The practical difference is brand and how your dentist or pharmacy supplies it.

Why a prescription? Because 1.1% sodium fluoride is far outside the over-the-counter ranges the FDA allows (Part 6). That is a regulatory line, not a sign the product is exotic. It is simply a stronger dose meant for people whose dentist has judged their risk to be high.

Part 4

The non-fluoride families: HAp, glass, CPP-ACP, arginine

The other four families use calcium and phosphate chemistry or, in arginine's case, a different approach altogether. None of their actives is an FDA-recognized anticavity drug ingredient, so in the US they are sold as cosmetics unless fluoride is added. The nano-hydroxyapatite and bioactive glass figures below come from our own brand reviews, checked 25 and 26 September 2026.

4. Nano-hydroxyapatite

Hydroxyapatite is the calcium phosphate mineral enamel is mostly made of. Toothpastes use a lab-made version, often at nano particle sizes, as a source of that mineral. Three products show how differently brands disclose it.

• Lumineux 10% Nano Hydroxyapatite Performance Whitening Toothpaste. The 10% is in the product name. Fluoride-free. The ingredient panel lists it simply as "Hydroxyapatite", which is normal INCI practice. $19.99 for a 2-pack of 3.75 oz tubes. Lumineux's "60+ studies" archive contains no hydroxyapatite titles, so the 10% claim is not backed by a study on this product. Our Lumineux review has the details.
• Dr. Jen Super Paste with Fluoride. Its ingredient panel states "Nanohydroxyapatite (nHAp) 10%" plus 0.22% sodium fluoride, about 1,000 ppm, under an FDA over-the-counter registration (NDC 84181-357-05). It is the one product in this family that combines nano-HAp with fluoride. $26.00 a tube; a fluoride-free 10% version is $18.50. A separate wholesale-site product line for the brand says "Replaces 5000 ppm fluoride". The registered fluoride strength, 0.22% sodium fluoride, is standard over-the-counter strength, not the 1.1% prescription strength described in Part 3. See our Dr. Jen review.
• Fygg Mild Mint. Fluoride-free. Fygg's FAQ gives the final in-tube concentration as 3.1% ("We add 20% of this 15.5% resulting in 3.1% per toothpaste tube"), using rod-shaped, uncoated nanoXIM particles with a median of 27.6 by 15.4 nm. $14.00 a tube. In a lab study funded by Fygg's parent company (Amaechi and colleagues, 2025, PMID 40744295), the product is labelled "Fygg (20% nanoXIM)". That 20% refers to the raw material Fygg buys, not the 3.1% in the tube, so "Fygg is 20% hydroxyapatite" is a misreading. Our Fygg review explains both numbers.

In the US, nano-hydroxyapatite is not in the FDA's list of anticavity actives, so these pastes are cosmetics, and only the fluoride in Dr. Jen's version has drug status. In the EU, nano-hydroxyapatite is regulated by concentration and particle shape (Part 6). For the mechanism side by side with fluoride and CPP-ACP, see our explainer on how the three actives work, and our nano-hydroxyapatite vs fluoride comparison covers the head-to-head evidence in more depth.

5. Bioactive glass

Bioactive glass does not contain hydroxyapatite. It is a glass that dissolves in saliva and releases calcium and phosphate ions, which settle on the tooth as a hydroxyapatite-like mineral layer. Two products carry it.

BioMin F (BioMin Technologies, UK). The brand's ingredient list reads: "Glycerin, PEG 400, Silica, Fluoro Calcium Phospho Silicate, Sodium Lauryl Sulphate, Titanium Dioxide, Aroma, Carbomer, and Potassium Acesulfame. Fluoride concentration is 530ppm." That is about a third of a standard 1,450 ppm paste, a deliberate choice according to BioMin. The glass percentage is not published on the retail pages; BioMin's own hosted trial summaries describe the tested product as "5% fluorocalcium phosphosilicate". BioMin gives its RDA, a measure of abrasiveness, as 68. In the UK it is a Class IIb medical device, not an FDA drug. The brand says: "BioMin ® works differently to provide a slow release of ions that create a higher level of clinically proven protection."

The catch: BioMin was out of stock worldwide on 26 September 2026, across UK, US and Australian and New Zealand stockists. Its homepage says: "Back In Stock Soon! ... Due to regulatory updates, supply is temporarily disrupted." You cannot buy it today. Our BioMin review tracks the situation.

NovaMin in Sensodyne Repair and Protect, sold outside the US. NovaMin is calcium sodium phosphosilicate, another bioactive glass. The FDA's DailyMed database lists no US Sensodyne product built on it: the US Sensodyne range there uses potassium nitrate, sodium fluoride and stannous fluoride. We could not read Sensodyne's own UK or Australian product pages, which load their content by script, so we cannot quote Haleon's current claim or percentage. Published trials describe the NovaMin comparator as "5% calcium sodium phosphosilicate", for example Ashwini and colleagues (2018, PMID 30166822), a dentin hypersensitivity trial. Treat 5% as a trial description, not a Sensodyne label figure.

6. CPP-ACP: a tooth cream, not a toothpaste

CPP-ACP is casein phosphopeptide with amorphous calcium phosphate, a milk-derived protein complex that holds calcium and phosphate in a form the tooth can take up. The best-known products are GC's MI Paste and MI Paste Plus, and the first thing to know is that they are not toothpastes. GC America's own page titles read "MI Paste: Topical Tooth Cream" and "MI Paste Plus: Topical Tooth Cream". You brush with your normal paste, then apply the cream and leave it in place for a few minutes.

• MI Paste (no fluoride). GC's page: "MI Paste contains RECALDENT (CPP-ACP)... a special milk-derived protein that can help decrease dentin hypersensitivity." GC's current US page states no CPP-ACP percentage; the often-repeated 10% figure is not on that page. GC lists uses including "For pregnant women" and "For children under six". There is no FDA drug listing for plain MI Paste, because CPP-ACP is not an FDA anticavity active. Tubes are 40 g.
• MI Paste Plus (with fluoride). The FDA label reads: "Sodium Fluoride 0.2% (w/w)... Anticavity", about 900 ppm fluoride. It is sold over the counter: DailyMed classifies the label as an OTC drug label, and GC's product page mentions no prescription. GC's framing: "MI Paste Plus supplies calcium, phosphate and fluoride needed for patients with poor saliva flow." Its use list does not repeat "children under six" or "pregnant women". A related product, MI Paste ONE, adds 5% potassium nitrate to 0.24% sodium fluoride.

Allergy warning, from GC: "RECALDENT (CPP-ACP) is derived from milk casein. Do not use on patients with a milk protein or hydroxybenzoates allergy." Our CPP-ACP explainer covers the chemistry and how the cream is applied.

7. Arginine

Arginine is an amino acid. In toothpaste it is used mainly against sensitivity, by blocking the small tubules in exposed dentin, and some brands add a caries angle. elmex Sensitive Professional (CP GABA, Colgate-Palmolive) uses Colgate's "PRO-ARGIN" technology; elmex's site says it closes the tubules leading to the nerve. elmex Sensitive Professional Repair and Prevent adds zinc. elmex does not state an arginine percentage on the pages we could reach, and it sells through pharmacies in Europe, not in the US, UK, Australia or Canada. Our elmex review and our arginine explainer cover both.

In the US, arginine is not an FDA anticavity or antisensitivity active. A DailyMed search for "Pro-Relief", the historical US name of Colgate's arginine sensitivity paste, returned no results on 26 September 2026. As a remineralization pick, arginine has the weakest evidence of the seven families (Part 5).

Part 5

What the studies show, and what they do not

Every study below was resolved in PubMed. For each one we give the design and one thing it does not show, because that second line is usually what marketing leaves out. Funding and conflicts are as each paper declares them.

Fluoride: the Cochrane review

Walsh and colleagues (2019, PMID 30829399), Cochrane Database of Systematic Reviews. A systematic review and network meta-analysis of 96 studies from 1955 to 2014, comparing fluoride toothpastes of different strengths with each other and with non-fluoride paste, in children and adults. Findings: 1,000 to 1,250 ppm and 1,450 to 1,500 ppm reduce caries compared with non-fluoride paste; 1,450 to 1,500 ppm slightly beats 1,000 to 1,250 ppm; and "the caries increments are similar for 1700 to 2200 ppm and 2400 to 2800 ppm fluoride toothpaste when compared to 1450 to 1500 ppm." In adults, 1,000 or 1,100 ppm reduces caries against non-fluoride paste. All five authors declared no known conflicts.

What it does not show: that going above about 1,500 ppm helps the general population. It found higher strengths up to 2,800 ppm "similar", and none of the 96 studies tested 5,000 ppm. That is why 5,000 ppm is a targeted prescription tool, not a general upgrade.

Nano-hydroxyapatite: two reviews that disagree in tone

Wierichs and colleagues (2022, PMID 35103837), Clinical Oral Investigations. An independent systematic review of 5 in vivo and 5 in situ human studies. It found that "under demineralization conditions, NaF was able to hinder demineralization, whereas nHA did not", and concluded that the low number of studies, short follow-ups and high risk of bias "do not allow for conclusive evidence on the efficacy of nHA." The authors declared no competing interests.

Pawinska and colleagues (2024, PMID 39471896), Journal of Dentistry. An updated systematic review and meta-analysis including 5 clinical trials and 8 in situ trials. Conclusion: "More studies now show that hydroxyapatite is effective as an anti-caries active ingredient in the absence of fluoride." Declared conflicts: two of the six authors are senior scientists at Dr. Kurt Wolff GmbH & Co. KG, which makes hydroxyapatite toothpaste, and all authors received travel grants from that company.

What neither shows: that nano-hydroxyapatite is superior to fluoride in a head-to-head trial at low risk of bias. Read them together. The more optimistic review has a declared manufacturer tie; the independent one calls the evidence inconclusive.

Hydroxyapatite: the human trials

Paszynska and colleagues (2023, PMID 37533523), Frontiers in Public Health. An 18-month double-blind non-inferiority trial in 189 adults (171 per protocol), comparing a fluoride-free hydroxyapatite toothpaste with a 1,450 ppm fluoride paste. No increase in decayed, missing or filled surfaces was seen in 89.3% of the hydroxyapatite group and 87.4% of the fluoride group, and the authors concluded the hydroxyapatite paste "was not statistically inferior". Three authors are employees of Dr. Kurt Wolff GmbH & Co. KG. What it does not show: equivalence or superiority in a tight sense, because a non-inferiority design with a 20-percentage-point margin only shows "not worse than, within that margin". It did not test children, high-risk patients or root caries.

Paszynska and colleagues (2021, PMID 33514787), Scientific Reports. A 1-year double-blind trial in 207 children (177 per protocol) comparing a fluoride-free microcrystalline hydroxyapatite paste, used three times a day, with a fluoride paste. Caries progression was seen in 72.7% versus 74.2%, within the non-inferiority margin. This paper declares no competing interests, though several authors overlap with the group's other papers that do. What it does not show: replication by an independent group, and it used micro-sized, not nano-sized, hydroxyapatite.

Amaechi and colleagues (2019, PMID 31839988), BDJ Open. A double-blind crossover in situ study: 30 adults wore appliances holding primary-tooth enamel blocks for 14 days per arm. A 10% hydroxyapatite paste "achieved comparable efficacy with 500 ppm F- in remineralizing initial caries and preventing demineralization." No competing interests declared. What it does not show: a comparison with standard 1,450 ppm adult toothpaste, since the fluoride comparator was a low 500 ppm, or results in children's own mouths.

5,000 ppm and root caries

León and colleagues (2025, PMID 40754061), Journal of Dentistry. A follow-up analysis of trial data on 2,071 root caries lesions in older adults, comparing 1,450 ppm with 5,000 ppm fluoride toothpaste over two years. With 5,000 ppm, 64% of lesions were active at the start, inactive at one year and still inactive at two; 30% stayed inactive throughout. With 1,450 ppm, only 17.8% followed the active-to-inactive pattern and 20.4% stayed inactive. The authors declared no competing interests. What it does not show: anything about enamel caries in younger people; root surfaces are cementum and dentin, and this is a secondary analysis of an earlier trial.

Chen and colleagues (2026, PMID 41720286), Journal of Dentistry. A network meta-analysis of 13 in vitro, 3 in situ and 12 clinical studies on root caries. High-concentration sodium fluoride was the most effective at reducing lesion depth, improving hardness and preventing new caries, and the authors note 1,450 ppm "might be insufficient to arrest active root caries in high-risk patients." One co-author, Robert Hill, is also a co-founder of BioMin. What it does not show: a single definitive trial; it pools study types of mixed quality, which the paper itself lists as a limitation.

CPP-ACP and bioactive glass

Yengopal and Mickenautsch (2009, PMID 19701818), Acta Odontologica Scandinavica. A meta-analysis that pooled 5 short in situ trials of 7 to 21 days and found a remineralization effect for chewing gum with 18.8 mg CPP-ACP over gum without it. What it does not show: long-term caries outcomes, or results for a toothpaste or cream, since most pooled data were on gum.

Rahmath Meeral and colleagues (2024, PMID 38690375), The Saudi Dental Journal. A systematic review of 11 randomized trials of CPP-ACP against topical fluorides, 3 to 12 months long; only 2 were rated at low risk of bias. The authors found "conflicting evidence" and results "in favor of both fluorides and CPP-ACP with similar clinical efficiency", and called for better trials. What it does not show: that CPP-ACP beats fluoride.

Mishra and colleagues (2026, PMID 42294495), Japanese Dental Science Review. A systematic review of 16 randomized trials in white-spot lesions and early enamel caries, 3 on bioactive glass and 13 on CPP-ACP. Bioactive glass beat fluoride and CPP-ACP in two studies; five studies favoured CPP-ACP over fluoride; CPP-ACP with fluoride did slightly better than without. The authors concluded: "Current evidence remains insufficient to replace fluoride as the standard." What it does not show: much on bioactive glass, which had only 3 of the 16 trials.

Arginine

Ástvaldsdóttir and colleagues (2016, PMID 27403876), Caries Research. A systematic review for the Swedish Council on Health Technology Assessment of randomized trials testing arginine in fluoride products. It found some trials had used non-fluoride toothpaste as the control, a weak comparator, and concluded: "At present there is insufficient evidence in support of a caries-preventive effect for the inclusion of arginine in toothpastes. More rigorous studies, and studies which are less dependent on commercial interests, are required." What it does not show: that arginine does nothing. It shows the trials so far do not settle the question, which is the most sceptical finding for any family in this guide.

Part 6

The rules: why 5,000 ppm is Rx, and the EU nano-HAp limit

The FDA's over-the-counter ranges

In the US, anticavity toothpastes sold over the counter follow a rule called a monograph, 21 CFR Part 355, which we read in the current eCFR text on 26 September 2026. It lists three permitted actives and their ranges:

• Sodium fluoride: 0.188% to 0.254%, for pastes with 850 to 1,150 ppm theoretical total fluorine.
• Sodium monofluorophosphate: 0.654% to 0.884% (850 to 1,150 ppm), or 1.153% for pastes with 1,500 ppm.
• Stannous fluoride: 0.351% to 0.474%.

That is the whole list. The ceiling is 1,500 ppm. A 1.1% sodium fluoride paste, about 5,000 ppm fluoride, fits none of these ranges, so it cannot be sold under the over-the-counter rule, and PreviDent 5000 Plus and Clinpro 5000 are prescription drugs instead. The monograph also caps a toothpaste package at 276 mg of total fluorine and gives its reason in plain words: "Due to the toxicity associated with fluoride active ingredients." Hydroxyapatite, CPP-ACP, arginine and bioactive glass do not appear in the list at all.

The same rule fixes the claim. The only anticavity indication allowed is "Aids in the prevention of dental" cavities, decay or caries. So when a US tube says "remineralizes" or "repairs enamel", that phrase is not the FDA-reviewed claim, whatever the active.

The EU limit for nano-hydroxyapatite

In the EU, nano-hydroxyapatite is allowed in oral care under conditions. The law in force, Commission Regulation (EU) 2024/858, sets a maximum of 10% in toothpaste and 0.465% in mouthwash. It rests on a 2023 opinion of the EU's Scientific Committee on Consumer Safety (SCCS/1648/22), which considered nano-hydroxyapatite safe at those levels only for rod-shaped particles, at least 95.8% of them with an aspect ratio below 3, not coated or surface-modified. The opinion does not cover needle-shaped particles or sprayable products.

On 26 June 2025, the same committee adopted a newer opinion (SCCS/1677/25) that considered nano-hydroxyapatite safe at up to 29.5% in toothpaste and 10% in mouthwash, for particles meeting a slightly different shape specification. The law in force (Regulation 2024/858) sets 10% and 0.465%, and a 2025 SCCS opinion considered higher levels safe. An opinion is advice, not a change in the law. Our article on whether nano-hydroxyapatite is safe covers the safety evidence in more detail.

How to read a remineralizing toothpaste label in five steps

• Find the active ingredient line. In the US, a fluoride paste has a Drug Facts box with the active and its percentage. A fluoride-free paste has an ingredient list instead; look for hydroxyapatite, calcium sodium phosphosilicate, fluoro calcium phospho silicate, CPP-ACP or arginine.
• Find the concentration. Fluoride pastes state it by law. For hydroxyapatite, look for a percentage on the pack or product page, and check whether it is the final concentration in the tube or a raw-material figure, as with Fygg's 3.1% and 20%.
• Check the format. A cream like MI Paste Plus is used after brushing, not instead of it.
• Check for prescription wording. 1.1% sodium fluoride or 5,000 ppm means a prescription product in the US.
• Check the warnings. Age limits on fluoride pastes, and the milk protein warning on CPP-ACP.

Part 7

Where a remineralizing gum fits, and where it does not

A toothpaste works for the two minutes you brush, twice a day. The remineralization tug of war goes on all day, especially after meals, when plaque acids drop the pH. That gap is what a chewing gum can address: chewing stimulates saliva, and a gum can carry its own active. Most of the data pooled in the 2009 CPP-ACP meta-analysis above came from chewing gum.

Minvelle is that kind of product. Each 1.9 g piece contains 5.7 mg of nano-hydroxyapatite and 817 mg of xylitol, with no fluoride. You chew one piece a day, after a meal, for at least 20 minutes. It goes on top of brushing with a toothpaste from this guide, and if that toothpaste is a fluoride paste, keep it.

What a gum cannot do

• It does not replace brushing. A gum does not remove plaque the way a toothbrush and paste do.
• It does not replace fluoride toothpaste. If your dentist has recommended fluoride, or a 5,000 ppm prescription, keep using it.
• It does not repair a cavity. No gum and no toothpaste fills a hole in a tooth.
• It does not bleach teeth. There is no peroxide in it; at most it helps with surface stains between brushings.
• It has not been in a clinical trial. There is no clinical trial on the finished Minvelle gum. What we publish is the dose, the full ingredient list and a batch certificate from lab testing of the finished gum.

Minvelle prints the dose on the box: 5.7 mg nano-hydroxyapatite per piece. See the gum.

In fairness

What each family does well

• Sodium fluoride has the largest and oldest evidence base in the field, is cheap and is sold everywhere.
• Stannous fluoride carries three FDA-label claims, anticavity, antigingivitis and antisensitivity, from one active.
• 5,000 ppm fluoride has the clearest recent evidence for arresting active root caries in older adults.
• Nano-hydroxyapatite is the fluoride-free option with the most human trial data, including an 18-month adult trial and a 1-year children's trial.
• Bioactive glass showed more consistent results than CPP-ACP in the 2026 white-spot review, especially in fluoride-containing versions.
• CPP-ACP had no adverse effect reported against fluoride in the 2024 review, and GC lists its fluoride-free version for children under six and for pregnant women.
• Arginine is a well-established sensitivity technology, and the 2026 root caries analysis named fluoride with arginine as a possible option for people who decline prescription fluoride.

The verdict

The best remineralizing toothpaste, in one paragraph

For most adults, the best remineralizing toothpaste is a standard fluoride toothpaste at 1,000 to 1,500 ppm, sodium or stannous, because no other active has comparable evidence. For high caries risk and active root caries, 5,000 ppm prescription sodium fluoride has the strongest recent data, and a dentist prescribes it. For people who prefer to avoid fluoride, a nano-hydroxyapatite paste that states its percentage is the best-supported alternative, with trials showing non-inferiority rather than superiority and with manufacturer ties in the most positive papers. Bioactive glass has promising white-spot data, but its best-known paste is out of stock. CPP-ACP is a cream to use after brushing, not a toothpaste. Arginine is a sensitivity technology whose caries evidence an independent review called insufficient.

Facts checked on 26 September 2026 from the sources below. If a brand or a regulator changes a page we quote, tell us and we will update this guide.

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