Dental Literature Watch · RCT · Prevention
1000 ppm fluoride toothpaste in 3-4-year-olds: a 24-month cluster RCT confirms it works, mostly in children who already have caries
TL;DR
- Daily 1000 ppm sodium fluoride toothpaste reduced the two-year caries increment in primary teeth of 3-4-year-olds compared with their usual toothpaste.
- Whole group: dmft increment 2.6 versus 3.3, dmfs 5.2 versus 6.4 (P < 0.05), scored at the cavitation level with WHO criteria.
- The effect sat in children who already had caries at baseline: dmft 3.1 versus 4.5, dmfs 7.2 versus 10.0 (P < 0.001).
- In caries-free children at baseline, no significant difference was found.
- Oral-health behaviours were comparable between groups, so the difference is not explained by brushing more often.
- Setting: kindergartens in Shenzhen, China, a non-fluoridated water area; 514 children completed.
The study
| Element | Detail |
|---|---|
| Design | Cluster-randomised controlled trial by kindergarten, 24 months |
| Population | Children aged 3-4 years; 514 completed |
| Intervention | Sodium fluoride toothpaste labelled 1000 ppm F supplied for home use |
| Control | No study toothpaste; children continued their usual toothpaste (fluoride content not stated in the abstract) |
| Outcomes | 24-month increments in dmft and dmfs, WHO criteria, essentially cavitation level |
| Result: all children | dmft 2.6 vs 3.3; dmfs 5.2 vs 6.4 (P < 0.05) |
| Result: caries at baseline | dmft 3.1 vs 4.5; dmfs 7.2 vs 10.0 (P < 0.001) |
| Result: caries-free at baseline | No significant difference |
💎 Insight — what this means chairside
Caries-active toddler: 1000 ppm, twice daily, now
The biggest absolute gain was 1.4 teeth and 2.8 surfaces over two years in children who already had decay.
That is the child whose parents are most likely to be using a low-fluoride "training" paste.
The biggest absolute gain was 1.4 teeth and 2.8 surfaces over two years in children who already had decay.
That is the child whose parents are most likely to be using a low-fluoride "training" paste.
Ask what paste is in the bathroom
The control arm kept its usual toothpaste, and the result still separated.
The conversation is not "fluoride or not", it is "which concentration, and is it actually being used".
The control arm kept its usual toothpaste, and the result still separated.
The conversation is not "fluoride or not", it is "which concentration, and is it actually being used".
Pair it with the behaviour
The authors tie the recommendation to twice-daily brushing and behavioural support.
A tube in the cupboard does nothing; the trial supplied the paste and still got only a partial reduction.
The authors tie the recommendation to twice-daily brushing and behavioural support.
A tube in the cupboard does nothing; the trial supplied the paste and still got only a partial reduction.
⚠️ The catch
Why this sits at 2 of 5
It confirms existing guidance on fluoride toothpaste from the first tooth rather than changing it.
The useful content is the subgroup split and the effect sizes, not a new recommendation.
It confirms existing guidance on fluoride toothpaste from the first tooth rather than changing it.
The useful content is the subgroup split and the effect sizes, not a new recommendation.
The control is undefined in the abstract
"Usual toothpaste" in a Chinese preschool population may be low-fluoride, fluoride-free, or a mix.
The comparison is therefore 1000 ppm versus whatever families bought, not 1000 ppm versus a defined lower concentration.
"Usual toothpaste" in a Chinese preschool population may be low-fluoride, fluoride-free, or a mix.
The comparison is therefore 1000 ppm versus whatever families bought, not 1000 ppm versus a defined lower concentration.
No fluorosis or safety data in the abstract
A two-year trial of 1000 ppm paste in 3-4-year-olds should report amount dispensed and any fluorosis signal; the abstract does not.
Smear or pea-sized amounts remain the practical safeguard.
A two-year trial of 1000 ppm paste in 3-4-year-olds should report amount dispensed and any fluorosis signal; the abstract does not.
Smear or pea-sized amounts remain the practical safeguard.
Non-fluoridated water, single city, cluster design
The authors restrict their recommendation to high-risk pre-schoolers in non-fluoridated areas.
Cluster randomisation by kindergarten also means fewer effective units than 514 children suggests.
The authors restrict their recommendation to high-risk pre-schoolers in non-fluoridated areas.
Cluster randomisation by kindergarten also means fewer effective units than 514 children suggests.
⚡ Bottom line
- 3-4-year-old with existing caries, non-fluoridated water → 1000 ppm fluoride toothpaste twice daily in a smear or pea-sized amount, plus behavioural support.
- Caries-free 3-4-year-old → this trial found no significant benefit over usual paste at two years; standard age-appropriate fluoride guidance still applies.
- Parents using a low-fluoride "training" paste on a child with decay → switch the concentration; that is the group where the effect was largest.
- Fluoridated community → the authors did not extend their recommendation here.
🧪 Questions
Tap an answer — instant grade, deciding line, and the trap.
A 3-year-old in a non-fluoridated area has two cavitated primary molar lesions. The parents brush her teeth twice daily with a fluoride-free training paste. Which recommendation does this trial best support?
In children with caries at baseline, 1000 ppm paste reduced the two-year increment from 4.5 to 3.1 dmft and from 10.0 to 7.2 dmfs, and the authors recommend it for high-risk pre-schoolers in non-fluoridated areas. Fluoride-free until six is the policy this trial argues against for a caries-active child. 5000 ppm is a prescription strength for older children and adults, not a tested arm here. Varnish alone addresses professional fluoride, not the daily home exposure the trial tested. Trap: varnish, which is what the clinic controls and is not what moved the number in this trial.
In which group did 1000 ppm fluoride toothpaste produce a statistically significant reduction in caries increment?
The reduction was significant in children with caries at baseline (P < 0.001) and not significant in those who were caries-free. Caries-free only is the reverse of the finding. Both equally and whole-group only both miss the subgroup split, which is the trial's most useful result. Trap: both groups, since fluoride toothpaste is usually presented as universal prevention.