Stannous fluoride and sodium fluoride toothpastes protect against decay about equally; the difference is that stannous fluoride also carries a tin ion that reduces gum inflammation, helps block the tubules behind sensitivity and resists acid erosion, at the cost of a stronger taste and, with older formulas, some surface staining. A systematic review of stabilised stannous fluoride toothpastes reported a similar or slightly higher anti-decay effect than other fluoride pastes, better results in a pooled analysis of eight-week sensitivity trials, and greater protection against erosion in seven of eight studies. For most people with healthy gums and no sensitivity, either salt does the job.
Written by Dr James Tran, BDent (University of Sydney), MICOI, GradDip (Oral Implants), general dentist at Lumi Dental in Melrose Park.
The short version
- The anti-decay agent in every fluoride toothpaste is the fluoride ion. Sodium fluoride, sodium monofluorophosphate and stannous fluoride are three ways of delivering it.
- In Australia, toothpastes for adults and children over six carry 1,000 to 1,450 ppm fluoride whichever salt is used.
- Stannous fluoride adds a tin ion. Reviews report less gingivitis and less sensitivity than with sodium fluoride controls, with wide variation between trials.
- Early stannous pastes could stain and tasted metallic; stabilised modern formulas have largely fixed this.
- If your gums bleed or your teeth zing with cold, try a stannous paste first. Otherwise use the fluoride paste you will use twice a day.
- Fluoride-free alternatives are a different question; see our comparison of hydroxyapatite and fluoride toothpaste.
Three fluoride salts, one fluoride ion
Turn over any Australian toothpaste and the active ingredient is one of three compounds. Sodium fluoride dissolves in saliva and releases fluoride straight away. Sodium monofluorophosphate holds its fluoride in a bound form that is released in the mouth. Stannous fluoride releases both a fluoride ion and a stannous, or tin, ion. The Oral Health Foundation lists these three as the types of fluoride used in toothpaste, and the Australian Dental Association's teeth.org.au site gives the usual strength for children over six and adults as 1,000 to 1,450 ppm, with 500 ppm for children aged 18 months to six years. The fluoride does the same work in all three, hardening the enamel repaired after each acid attack, which is why the ppm figure matters more than the salt for decay prevention.
What the tin ion adds: gums, sensitivity and erosion
Gums and plaque
Stannous ions are antibacterial. The evidence is consistent in direction and less so in size. A systematic review and meta-analysis of randomised trials comparing stannous fluoride pastes with other fluoride pastes found better gingival index scores with stannous, though the pooled difference was modest and a second gum index did not reach significance. A review of stabilised stannous fluoride also reported significant reductions in calculus build-up and bad breath. Our article on bleeding gums when brushing explains what the hygiene team looks for before recommending a paste.
Sensitivity
Cold sensitivity usually means exposed dentine, where tiny tubules run towards the nerve. Stannous deposits are thought to settle on the dentine and partially block those tubules, unlike the potassium nitrate in many sodium fluoride sensitivity pastes, which calms the nerve instead. The review by Konradsson and colleagues included 11 sensitivity studies, rated most at low or medium risk of bias, and found a mean difference in favour of stannous fluoride across six eight-week trials. In my experience the relief builds over two to four weeks of twice-daily use, and fades if you stop.
Erosion
Acid from soft drinks, citrus, wine or reflux softens enamel without any bacteria involved. The same review reported greater anti-erosive potential for stannous fluoride in seven of the eight erosion studies it found, while rating their risk of bias as high. The tin is thought to form an acid-resistant layer on the enamel surface, a useful extra alongside the diet changes in our guide to enamel erosion.
The trade-offs: stain, taste and price
Stannous fluoride is not new. The first toothpaste with a clinically proven anti-decay effect contained it, and the review of stabilised formulas notes that the early version had a known limitation: extrinsic staining, a brown film on the tooth surface. Manufacturers later stabilised the stannous so it stays active without staining as readily, and the same review found no difference in stain between stabilised stannous pastes and controls, though it rated those studies as high risk of bias. Any surface stain that does appear sits on the enamel rather than in it and comes off at a professional clean.
Taste is the other objection. Some patients I see describe stannous pastes as metallic or drying, and that is reason enough to choose sodium fluoride, because the paste you dislike is the paste you skip. Stannous products also tend to cost more. One point of fairness: many trials in these reviews were manufacturer-funded, so the size of the benefit deserves caution.
Sodium fluoride and stannous fluoride side by side
| Feature | Sodium fluoride (or monofluorophosphate) | Stannous fluoride |
|---|---|---|
| Decay prevention | Well established at 1,000 to 1,450 ppm | Similar or slightly higher in the reviewed studies |
| Gingivitis and plaque | Fluoride alone has little effect on gums | Modest, consistent reduction in gingivitis; plaque results mixed |
| Sensitivity | Relies on an added agent such as potassium nitrate | Tin deposits help block dentine tubules; favoured in pooled trials |
| Erosion protection | Some, from fluoride | Greater in most studies reviewed |
| Calculus and bad breath | No specific effect | Reductions reported for stabilised formulas |
| Staining | Not an issue | Possible with older formulas; largely resolved in stabilised versions |
| Taste | Neutral | Some find it metallic or drying |
| Price | Usually lower | Usually higher |
The single rule: if your gums bleed or your teeth zing, start with stannous; if neither, use the fluoride paste you like
If you have bleeding gums, recurrent sensitivity to cold or signs of acid wear, a stabilised stannous fluoride paste is a reasonable first change, used twice a day for at least a month before you judge it. If you have none of those, a sodium fluoride or monofluorophosphate paste at 1,000 to 1,450 ppm protects against decay just as well, and the version you enjoy using is the right one. The one situation where I would not rely on either is a high decay risk, which belongs to the prescription-strength pastes described below.
How to get the most out of any fluoride toothpaste
Technique matters more than the salt. teeth.org.au recommends brushing twice a day for two minutes with a soft-bristled brush, a pea-sized amount of paste for children over three and adults, and a smear for children aged 18 months to three; our guide to children's fluoride toothpaste covers the amounts by age. Replace the brush every three months, and avoid food or drink after the night-time brush so the fluoride stays on the teeth overnight. I usually suggest spitting out the excess rather than rinsing with water, which washes most of the fluoride away.
High-fluoride prescription pastes are a separate category
A stannous paste is not a "stronger" toothpaste; its fluoride content matches a standard paste. The stronger category is high-fluoride toothpaste, which the Oral Health Foundation lists at 2,800 ppm from age ten and 5,000 ppm from age 16 for people at very high risk of decay, with gum recession, dry mouth, or after head and neck radiotherapy. teeth.org.au notes that an Australian dentist may recommend a higher-fluoride paste where there is severe decay or high risk. These pastes are for the person they were recommended to, not the family bathroom.
How we approach this at Lumi Dental
Toothpaste advice at Lumi Dental follows the examination. The dentist checks for decay, recession, cracks and acid wear, since sensitivity has several causes and a paste treats only one of them. The hygiene team of oral health therapists then matches the recommendation to what they see: a stabilised stannous paste for inflamed gums or erosion, a potassium nitrate or stannous paste for sensitivity, a high-fluoride paste where decay risk is high, and fluoride varnish at the clean where it is likely to help. The team names product types rather than brands. A general check-up at Lumi Dental is the place to start if you are unsure.
Questions patients ask
Is stannous fluoride better than sodium fluoride?
For decay prevention they are about equal. Stannous fluoride has extra benefits for gingivitis, sensitivity and erosion in the trials reviewed, so it is better for people with those problems and no better for people without them.
Does stannous fluoride toothpaste stain your teeth?
Older formulas could leave a brown surface stain. Modern stabilised stannous pastes rarely do, and any stain that appears is on the surface and is polished off at a clean.
Can I use stannous fluoride toothpaste every day?
Yes. The trials reviewed used it twice daily for months, and the fluoride content is the same as a standard paste. Our article on whether fluoride is safe covers the wider question.
Which toothpaste is best for sensitive teeth and gums together?
A stabilised stannous fluoride paste covers both in one tube. Give it a month of twice-daily use, and if the sensitivity persists, have the tooth examined.
Why does stannous fluoride toothpaste taste metallic?
The tin ion has a slightly astringent taste that most people stop noticing within a week or two. If it bothers you, a sodium fluoride paste is a fine alternative, and you can ask the team for alternatives.
Not sure which toothpaste suits you? Book a check at Lumi Dental in Melrose Park
If your gums bleed or your teeth react to cold, a check lets the team at Lumi Dental look first and recommend second. Patients come to Melrose Central from Melrose Park, Ryde, Parramatta, Ermington and Rydalmere, with on-site parking. See our current offers or read about general dentistry at Lumi Dental.
Sources
- Konradsson K and colleagues. Stabilized stannous fluoride dentifrice in relation to dental caries, dental erosion and dentin hypersensitivity: a systematic review. American Journal of Dentistry (PubMed)
- Clark-Perry D, Levin L. Comparison of new formulas of stannous fluoride toothpastes with other commercially available fluoridated toothpastes: a systematic review and meta-analysis. International Dental Journal (PubMed)
- Johannsen A and colleagues. Effects of stabilized stannous fluoride dentifrice on dental calculus, dental plaque, gingivitis, halitosis and stain: a systematic review. Heliyon (PMC)
- Australian Dental Association (teeth.org.au): Tips for choosing toothpaste
About the author
Dr James Tran is a general dentist at Lumi Dental in Melrose Park. He holds a BDent from the University of Sydney and a Graduate Diploma in Oral Implants, and is a Member of the International Congress of Oral Implantologists (MICOI).
This article is general information only and is not a substitute for an examination and individual advice from a registered dental practitioner. Suitability for any treatment varies from person to person.
