CATEGORY: DISEASE PREVENTION
A toddler with deep cavities usually faces the drill, and often sedation or even a trip to an operating room to tolerate it. A large randomized trial now shows a gentler option holds up: a liquid called silver diamine fluoride, brushed painlessly onto the cavity, stopped half of treated cavities from getting worse at eight months, 50.2% against 17.4% with a placebo liquid.1 That’s roughly one extra arrested cavity for every three treated. The children were one to six years old. Nothing was drilled.
Painted on in seconds, checked for eight months
The trial enrolled 830 young children with severe early childhood tooth decay, averaging around 11 affected baby teeth each, across medical, dental and community settings including preschools and Head Start programs. Silver diamine fluoride is a clear solution of silver, which kills the bacteria eating the tooth, and fluoride, which hardens the damaged surface. Applying it takes about as long as painting a fingernail. Each child got either the real liquid or a lookalike placebo at the start and again at six months, and neither the families nor the dentists scoring the teeth knew which. Random selection decided. Examiners then tracked every treated cavity at three, six and eight months to see whether the decay had gone hard and inactive, which dentists call arrest, or kept advancing. Arrest isn’t a cosmetic judgment. An examiner probes the spot, and decay that has hardened no longer gives way.
The gap opened fast and held
By three months, 57.5% of cavities treated with the real liquid had stopped progressing, against 18.8% with placebo. The gap barely moved after that. At eight months the figures were 50.2% and 17.4%, a difference of about 33 percentage points that the trial pegs with reasonable precision, between roughly 22 and 43 points. Seventy percent of the children completed every scheduled visit, and about one in ten of the rest were lost to pandemic-era interruptions rather than anything about the treatment. Side effects looked the same in both groups: 47.3% of treated children had some adverse event against 43.3% on placebo, events judged treatment-related ran 22.9% against 22.2%, and exactly 7.5% of each group discontinued because of one. Mostly these were minor. Rates of dental pain didn’t differ either, which matters for a treatment whose selling point is that it doesn’t hurt. The National Institutes of Health, which funded the trial, describes the approach as a way to keep decay from worsening while a child grows old enough for definitive care, not a replacement for fillings where they’re truly needed.
The trade-off is a black spot
Silver diamine fluoride permanently stains the decayed part of the tooth dark. On a visible front tooth, some families will mind. These were baby teeth, which fall out on their own, and the stain marks only the damaged area, not healthy enamel. Against the alternative, drilling on a frightened two-year-old or scheduling general anesthesia, many parents may see a black spot differently. Cavities remain one of the most common chronic diseases of early childhood, and untreated decay can mean pain, infection and missed preschool. A painless liquid that halts half of them changes what a first dental visit can accomplish.
Key Takeaways
- In a randomized, placebo-controlled trial of 830 children aged one to six, silver diamine fluoride stopped 50.2% of treated cavities from progressing at eight months versus 17.4% with placebo.
- The liquid is brushed on without drilling or numbing, and side effects matched the placebo group.
- It permanently stains the decayed part of the tooth dark, the main drawback families weigh.
- Researchers frame it as a way to halt decay in young children, not a substitute for fillings when those are needed.
References
- Fontana M, Moursi A, Gonzalez-Cabezas C, et al. Efficacy of silver diamine fluoride on young children with severe early childhood caries: a randomized clinical trial. JAMA Pediatrics. 2026; doi 10.1001/jamapediatrics.2026.2567. link