Choosing Toothpaste: Fluoride, Abrasivity and Claims

/ The Brand Name on the Tube Does Not Tell You What Is Inside

The best toothpaste for you is the one carrying the right active ingredient for your actual problem, and the single most useful thing to know before you buy anything is that the brand name will not tell you which active that is. The same product name can be two chemically different toothpastes depending on which country you are standing in.

Sensodyne Repair & Protect is the clearest example. In the United States the label lists stannous fluoride 0.454 per cent as the active ingredient and NovaMin appears nowhere on it. In the United Kingdom the same box is built on calcium sodium phosphosilicate (NovaMin) at 5 per cent with sodium fluoride alongside it. Those are two different ways of sealing a dentine tubule, sold under one name.

It is not an isolated case. Colgate Sensitive Pro-Relief is an arginine toothpaste in the UK at 8 per cent; the US Pro-Relief label is a stannous fluoride product with no arginine on it at all. Parodontax is a stannous fluoride paste in the US, while the UK version is sold under the name Corsodyl and is built on sodium bicarbonate with sodium fluoride.

The rule is not that every brand changes across borders, and it is worth saying so plainly: Sensodyne Rapid Relief is stannous fluoride 0.454 per cent in both markets. The rule is that the name is not evidence. The ingredient panel is, and everything below is organised around what has actually been measured for each of those ingredients.

/ How Much Fluoride, and Why American Tubes Say Less Than British Ones

Fluoride is the one ingredient with evidence heavy enough to be non-negotiable, and the number on a US tube is genuinely lower than the number on a UK one in most categories. A Cochrane review of 96 randomised studies found high- and moderate-certainty evidence that toothpaste at 1,000 to 1,250 ppm and at 1,450 to 1,500 ppm reduced caries increment against non-fluoride paste (standardised mean difference -0.28 and -0.36), with only a slight further gain from moving up between those two bands (PubMed 30829399).

The gap is regulatory rather than commercial. The US over-the-counter monograph caps sodium fluoride and stannous fluoride toothpaste at 850 to 1,150 ppm total fluorine, which is why almost every American stannous or sodium fluoride paste calculates out at roughly 1,100 ppm. UK guidance runs higher: the national oral health toolkit tells clinicians to advise brushing with 1,350 to 1,500 ppm fluoride toothpaste, and the UK products checked here sit at 1,400 to 1,450 ppm.

"American toothpaste has less fluoride" is still too broad a statement to make. The same US monograph permits a higher-potency monofluorophosphate entry at 1,500 ppm, and Colgate Optic White Pro Series uses it. The difference is real within the stannous and sodium fluoride categories, not across the whole market.

One label trap is worth learning, because it produces confidently wrong numbers. US tubes print a phrase like "0.15% w/v fluoride ion". That is not 1,500 ppm. It is a weight-per-volume expression, and the weight-per-weight figure quoted in the literature works out near 1,100 ppm for the same paste.

/ Best Toothpaste for Sensitive Teeth: What the Trials Rank, and Which Tube Carries It

Sensitivity is the category where the evidence separates the ingredients most sharply, and one widely sold active does not work. A meta-analysis of 31 randomised controlled trials compared each desensitising agent against placebo and put arginine furthest ahead (standardised mean difference -3.25), followed by potassium combined with stannous fluoride (-2.50), calcium sodium phosphosilicate (-2.36), stannous fluoride alone (-1.37) and potassium-containing pastes (-1.28) (PubMed 25483802).

Translating that ranking onto a shelf, with the labels checked rather than assumed:

• Arginine 8 per cent is in Colgate Sensitive Pro-Relief and its successor Colgate Sensitive Instant Relief in the UK. The US product sold under the Pro-Relief name is not an arginine paste.
• Calcium sodium phosphosilicate (NovaMin) 5 per cent is in the UK version of Sensodyne Repair & Protect, not the US one.
• Potassium nitrate 5 per cent is in Sensodyne Pronamel and in Crest Pro-Health Sensitivity Relief.
• Stannous fluoride 0.454 per cent is in Sensodyne Rapid Relief in both markets, and in Crest Pro-Health Advanced Protection.

The finding worth knowing is the negative one. Strontium-containing toothpaste, sold for sensitivity for decades, showed no statistically significant effect in the pooled analysis of four studies (SMD 0.05). Heterogeneity across these trials was very high, so read the ranking as a direction rather than a precise league table, and give any of them several weeks: desensitising pastes build their effect slowly, and switching after five days is the commonest way to conclude wrongly that one failed.

/ Best Toothpaste for Plaque and Gum Health

Where the complaint is bleeding gums and plaque rather than decay, the ingredient to look for is stannous fluoride rather than the more common sodium fluoride, because it acts on the bacteria at the gum margin as well as delivering fluoride to the tooth. On US labels that is Parodontax Complete Protection, Crest Pro-Health Gum Detoxify and Colgate Total, all at stannous fluoride 0.454 per cent.

Colgate Total is worth a sentence of its own, because it is not the product it used to be. Its 2018 US label was sodium fluoride with triclosan at 0.30 per cent; the current label is stannous fluoride and triclosan is gone. Advice written before that change, and there is a great deal of it still online, describes a formulation that no longer exists.

The evidence for stannous needs reading with its authorship in view. The largest synthesis, 14 randomised trials with 1,287 participants, found that bioavailable stannous fluoride toothpaste outperformed sodium fluoride and monofluorophosphate controls for dentine hypersensitivity and gave an 83 per cent benefit over control pastes on erosive wear measured by profilometry (PubMed 33383100). That review was written by researchers at the manufacturer and drawn from the manufacturer's own study archive, which the paper states openly. It points the same way as the independent evidence above, which is why it is cited, but it is not the same grade of evidence as a Cochrane review.

A practical caution: stannous fluoride can leave surface staining on some people, more so where plaque control is poor. It polishes off, but it surprises anyone who was not warned. And no toothpaste resolves established gum disease; where the gums bleed consistently the paste supports treatment of gum disease within our periodontology service rather than replacing it.

/ Best Whitening Toothpaste, and What It Cannot Do

Whitening toothpaste removes surface stain; it does not change the colour of the tooth itself, and the difference between the two products on the shelf is whether the tube contains a bleaching agent at all. A systematic review of randomised trials comparing whitening with conventional dentifrices did find significant differences in measured tooth colour, but the authors framed the result as potential in tooth whitening rather than as a substitute for bleaching (PubMed 30510576).

Crest 3D White Radiant Mint lists sodium fluoride as its active ingredient and contains no peroxide; hydrated silica does the work, which means the mechanism is polishing away stain. Colgate Optic White Pro Series does contain hydrogen peroxide at 5 per cent w/v, listed among the inactive ingredients alongside monofluorophosphate. If you have been comparing the two and wondering why they behave differently, that is why.

Activated charcoal deserves naming because it is marketed hardest and has been tested. A systematic review of eleven in vitro studies concluded that charcoal-based toothpastes whiten less than the alternatives and can be considered less safe because of their higher abrasive potential (PubMed 36183933). The reviewers rated the risk of bias in the underlying studies as medium to high and the work was done on extracted teeth, so take the abrasion signal seriously and any precise figure lightly. There is no detoxifying mechanism involved; charcoal adsorbs substances in a beaker, and a tooth is not a beaker.

If the shade of the tooth itself is what bothers you, that only moves with in-clinic teeth whitening, part of our aesthetic dentistry work. Toothpaste can hold a result; it cannot create one.

/ Abrasivity: The Number Almost Nobody Publishes

Abrasivity is measured as RDA, relative dentine abrasivity, and the American Dental Association sets the ceiling for daily use at 250 RDA, measured by the method in ISO 11609. Below that a paste is considered safe for long-term use on enamel.

The problem is that you usually cannot find the number. Manufacturers do not publish per-product RDA values; among all the brands checked here, the only published figure was for Sensodyne Sensitivity, Gum & Enamel at RDA 20.01. The RDA tables that circulate online, ranking dozens of brands, are not a usable substitute: the same undated, unattributed table appears on clinic sites and blogs by the dozen with no traceable origin, and the widely quoted low-medium-high bands are defined by neither the ADA nor ISO.

What does exist is peer-reviewed measurement of named products, and the spread is wide. Published work has put Signal White System at 143, Colgate Total Original at 100, Colgate Optic White Dazzle at 111 and one whitening paste as low as 12, all on the same RDA scale.

The pattern behind those numbers is the one to take away: the quickest way to make teeth look cleaner within a week is to scrub harder rather than to change anything chemically, which is exactly the mechanism behind the charcoal finding above. Enamel does not grow back, and abrasion shows up years later as thinning at the necks of the teeth and rising sensitivity rather than as anything you notice while brushing.

/ What "Dentist Recommended" and the ADA Seal Actually Mean

An approval seal tells you a product does what it claims, not that it beats the tube next to it. The ADA describes its Seal as meaning that the association "has reviewed scientific evidence to determine that the product meets rigorous standards for safety and effectiveness", accompanied by a statement identifying the specific benefits evaluated. Several products on the same shelf can hold the same seal for different claims.

That the seal is not a ranking is written into the rules around it: the ADA states that comparative advertising claims for competing products and services will not be accepted. So a seal is a reasonable basis for excluding an unregulated product and a poor basis for choosing between two regulated ones.

"Dentist recommended" is weaker still. It is a marketing phrase rather than a regulated one, and it usually rests on a survey rather than a trial. When a dentist genuinely recommends a toothpaste, they are recommending an active ingredient for a specific problem in a specific mouth; the phrase on the packaging has that specificity stripped out.

Read the seal as a floor and the ingredient panel as the actual decision. The things that separate two sealed products are the fluoride concentration, the desensitising active if there is one, and the abrasivity, and two of those three are printed on the box.

/ SLS-Free Toothpaste: When the Foaming Agent Is the Problem

For people who get recurrent mouth ulcers, the foaming agent is one of the few times that changing brand has measured support behind it. A systematic review of four double-blind crossover trials with 124 participants found that toothpaste free of sodium lauryl sulfate reduced the number of ulcers, how long they lasted, how often they returned and how much they hurt (PubMed 30839136).

Finding one is harder than it looks, because SLS-free is a property of the product and not of the brand. Sensodyne Pronamel is SLS-free while several other Sensodyne variants are not; Tom's of Maine has SLS-free products and also has variants that list sodium lauryl sulfate. Every Crest, Colgate and Parodontax product whose label was checked for this article contains it.

Products whose labels confirm no SLS include Sensodyne Pronamel, CloSYS Anticavity, Biotene, several hello and Tom's of Maine variants, Verve Ultra and Squigle Enamel Saver. Most replace it with cocamidopropyl betaine or a glutamate surfactant, which is why they foam less; that is the trade, and it is a cosmetic one.

The scale of the choice is wider than most people assume. A 2024 survey of 160 toothpastes across five major supermarket chains in Istanbul found SLS in 67 per cent of them, which means roughly a third of the shelf is already free of it if you read the panel.

/ When the Toothpaste Is Not the Problem

Most of what toothpaste gets blamed for belongs to something else, and switching tubes delays finding it. Plaque that returns within a day is usually a technique and interval problem rather than a formulation one; staining that keeps returning is usually diet; and pain that keeps returning is a clinical finding waiting to be examined.

Sensitivity that arrives suddenly, sits in one tooth, or wakes you at night does not belong to this article at all. That pattern behaves nothing like generalised cold sensitivity and needs looking at, because a cracked tooth or an exposed root is a different problem with a different fix.

The short version of everything above: use a fluoride toothpaste, read the back of the tube rather than the front, pick the active that matches your actual complaint rather than the brand you recognise, and remember that the same name can mean a different formulation in a different country. Then spend the attention you were giving the packaging on how long and how gently you brush instead.