You probably know the parent moment. The dentist spots a cavity, and your child is barely old enough to sit still in the chair.
For many families, the drill, the needles and the sedation are what keep a small cavity from being treated at all.
A large US trial just published in JAMA Pediatrics shows a different route.
Researchers found that a liquid painted onto decayed baby teeth stopped the decay in more than half of them within six months.
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The liquid is called silver diamine fluoride, or SDF for short. A dentist dabs it on with a small sponge-tipped applicator. The whole application takes only seconds per tooth. No drill. No shot. No sedation.
How the silver and fluoride work together
The silver fights the bacteria that cause cavities. The fluoride hardens what is left of the tooth so new damage is slower to form. Together they halt a cavity in place.
That is the key point for parents. SDF does not rebuild the tooth. It stops the hole from growing.
What the trial actually measured
The study ran as a phase III placebo-controlled trial in Michigan, New York and Iowa. It enrolled 830 children under the age of 6, many through Head Start programs.
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Half received 38 percent SDF on their active cavities. The other half received a placebo liquid. Both groups were checked again at six months.
In the SDF group, 54 percent of the treated cavities had stopped progressing. In the placebo group, the share was 22.5 percent. The treatment roughly doubled the number of cavities that went quiet.
Serious side effects were rare. Treatment-related side effects appeared in both groups at nearly identical rates, around 22 percent each.
The research was led by Margherita Fontana, professor at the University of Michigan School of Dentistry, with co-leads at New York University, the University of Iowa and Indiana University. She has described the approach as safe and effective even for children as young as one.
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The one tradeoff parents should know about
The silver in SDF permanently darkens the decayed part of the tooth. On a back molar it is often hidden. On a front tooth it can be very visible, and it does not wash off or wear away.
Dentists usually explain this to families before the first application.
For many parents, a dark spot that will fall out with the baby tooth is a far smaller problem than a drill. For others, it is a dealbreaker.
Where SDF stands in the United States right now
The US Food and Drug Administration cleared SDF in 2014 as a treatment for tooth sensitivity. Using it to stop cavities is currently off-label, according to the American Dental Association.
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The research team said the new trial provides the clinical data needed to apply for FDA approval of cavity treatment as an officially recognized use. The trial was funded with more than $12 million from the National Institute of Dental and Craniofacial Research.
Parents interested in SDF for their child can ask their pediatric dentist whether the office uses it. The product is already sold in the US under the brand name Advantage Arrest.
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This article is made and published by Ida-Marie Palm Varbæk, who may have used AI in the preparation.