A two-year cluster-randomized trial in Shenzhen kindergartens, published online on September 30, 2026 in the Journal of Dentistry, found that preschoolers given a toothpaste labelled 1,000 ppm fluoride had smaller increases in decayed, missing and filled primary teeth than children who kept using their usual toothpaste. The benefit was concentrated in children who already had caries at the start. For Canadian practices, the result fits the caries-risk-based approach the Canadian Dental Association (CDA) already recommends.
Fluoride toothpaste for young children is a question parents often bring to the chair, and an easy one to answer vaguely. As of October 2026, a new randomized trial adds clinical data on a specific concentration (1,000 ppm) in a specific age group (3 to 4 years), and it is worth knowing what it did and did not show before your team repeats the headline.
What did the trial test?
The study, titled "Caries prevention with 1,000-ppm fluoride toothpaste in preschool children: a 24-month cluster-randomized controlled trial," was published in the Journal of Dentistry (article 107086). The authors are Zhang J, Xie Q, Chu CH, Zhang X, Yu W, Shen Y and Lo ECM, with affiliations that include the Eighth Affiliated Hospital of Sun Yat-sen University and the Faculty of Dentistry at the University of Hong Kong.
According to the abstract, the trial ran for 24 months in kindergartens in Shenzhen, China, and enrolled children aged 3 to 4. Randomization happened at the kindergarten level (a "cluster" design), not child by child:
- Test kindergartens: children received a sodium fluoride toothpaste labelled as containing 1,000 ppm F, for use at home.
- Control kindergartens: children did not receive the study toothpaste and continued using their usual toothpaste.
Examiners recorded caries using World Health Organization criteria, which the authors describe as essentially at the cavitation level. The primary outcomes were the two-year increase in dmft (decayed, missing and filled primary teeth) and dmfs (the same count at the surface level). A total of 514 children completed the trial.
What did the researchers find?
Across all children who finished, the test group had smaller dmft and dmfs increments over two years than the control group. The abstract reports a mean dmft increment of 2.6 versus 3.3, and a mean dmfs increment of 5.2 versus 6.4 (P<0.05).
The more striking split came by baseline status. Among children who already had caries when the trial began, the difference was larger: 3.1 versus 4.5 for dmft and 7.2 versus 10.0 for dmfs (P<0.001). Among children who were caries-free at baseline, the authors found no significant difference between groups. The abstract also reports that oral health behaviours were comparable between the two arms.
How should Canadian practices read these numbers?
Read them as support for risk-based fluoride advice, not as a new universal rule. Three details from the abstract matter when you translate the study to a Toronto or GTA patient base.
1. The control group was not "no fluoride"
Control children kept using their usual toothpaste, and the abstract does not state what fluoride concentration that was. The comparison is therefore "a labelled 1,000 ppm product supplied to families" versus "whatever families already used," not fluoride versus no fluoride. That is a practical, real-world comparison, but it limits how precisely the result can be pinned to concentration alone.
2. Caries status at baseline drove the effect
The authors' own conclusion is that daily use of 1,000 ppm fluoride toothpaste reduces caries increment in primary teeth "particularly in caries-active preschool children." For the caries-free group, the trial found no significant difference. That lines up with how your team already triages: children with active lesions or a history of decay are where intensified home-care advice is most likely to pay off.
3. The authors framed their recommendation narrowly
In the abstract's clinical-significance statement, the authors recommend 1,000 ppm fluoride toothpaste for preschoolers at high caries risk living in areas without fluoridated water, alongside behavioural measures such as brushing twice a day. That qualifier is worth checking against your own patients' home water supply rather than assuming either way.
Pro Tip: Add one line to your paediatric recall template that records whether the family's home water supply is fluoridated. It takes a moment to ask, and it makes your fluoride advice traceable when a parent asks why their child's recommendation differs from a sibling's or a neighbour's.
What does the Canadian Dental Association recommend?
The CDA's current Position on Fluoride, approved by its Board of Directors in February 2021, states that the CDA supports the appropriate use of fluoride and that more than 50 years of research shows fluoride is safe and effective in preventing caries. Several points in that statement map directly onto this trial:
- Risk assessment first. The CDA recommends that patients consult their dentist for an assessment of their caries risk and for professional advice on daily fluoride products, including toothpastes, rinses, lozenges, chewable tablets and drops.
- Early first visits. Children should see a dentist no later than 12 months of age or within six months of their first tooth erupting.
- Under age three. Until age three, the CDA recommends daily fluoride products if the child is determined to be at risk for caries.
- Professional products. The statement lists gels, 5% sodium fluoride varnish and 38% silver diamine fluoride as professional options to discuss, and says that unless recommended by the dentist or tied to a caries risk assessment, 5% sodium fluoride varnish should be received only once per six-month period.
- The CDA Seal. Patients are advised to look for the CDA Seal when buying daily oral care products.
Note that the CDA describes itself as an association with no regulatory role. In Ontario, dentists are obligated to maintain the standards of practice of the profession, including those published by the Royal College of Dental Surgeons of Ontario (RCDSO); the CDA position is national professional guidance, not a regulatory standard.
Pro Tip: When a parent asks "which toothpaste should we buy," answer in two parts: the child's risk level (from your assessment) and the CDA Seal on the package. That keeps the conversation anchored to the patient, not to a brand.
What should your practice do with this study?
Nothing dramatic, and that is the point. For practices in Toronto, Mississauga, Markham and the rest of the GTA, the trial reinforces a risk-based workflow that fits the CDA's guidance:
- Document caries risk at every paediatric recall. The trial's clearest benefit appeared in children with existing caries. Your risk notes are what let you identify those children consistently.
- Give concentration-specific home-care advice to higher-risk children. "Use a fluoride toothpaste" is less useful than naming what to look for on the label, based on your assessment and the product's directions.
- Pair product advice with behaviour. The authors recommended fluoride toothpaste together with behavioural measures such as twice-daily brushing. A product without the habit is half the plan.
- Keep the study in proportion. It is one trial in one city, reported here from its published abstract. It adds to the evidence base; it does not replace your clinical judgment or the CDA's risk-based framework.
EBIKO Dental will continue monitoring new research on paediatric caries prevention and how it connects to Canadian guidance. For clinical supplies for your practice, visit EBIKO Dental.
Sources
- Zhang J, Xie Q, Chu CH, et al. Caries prevention with 1,000-ppm fluoride toothpaste in preschool children: a 24-month cluster-randomized controlled trial. Journal of Dentistry, 2026, article 107086. doi:10.1016/j.jdent.2026.107086 (record: Europe PMC 42815560)
- Canadian Dental Association. CDA Position on Fluoride (approved February 2021).
Frequently Asked Questions
Q: Does 1,000 ppm fluoride toothpaste prevent cavities in preschool children?
In a 24-month cluster-randomized trial of 514 children aged 3 to 4 in Shenzhen kindergartens, published in the Journal of Dentistry in September 2026, children given a toothpaste labelled 1,000 ppm fluoride had a smaller increase in decayed, missing and filled teeth (2.6 vs 3.3 dmft) than children using their usual toothpaste. The difference was significant in children who already had caries, but not in children who were caries-free at the start.
Q: What does the Canadian Dental Association recommend about fluoride for young children?
The CDA's 2021 position recommends a dentist's caries risk assessment and professional advice on daily fluoride products, a first dental visit by 12 months of age or within six months of the first tooth, and daily fluoride products before age three if the child is at risk for caries. It also advises looking for the CDA Seal on daily oral care products.
Q: Should every child switch to a 1,000 ppm toothpaste after this study?
The study's authors recommended 1,000 ppm toothpaste specifically for preschoolers at high caries risk in areas without fluoridated water, alongside twice-daily brushing. In Canada, the CDA ties daily fluoride advice to an individual risk assessment, so the right product for a given child is a decision for that child's dentist.