Can you stop a toddler’s cavity without a dental drill?
Yes. In a trial of 830 young children, silver diamine fluoride painted onto active cavities stopped 54.0% of them from getting worse, compared with 22.5% of cavities treated with a placebo liquid. No drilling, no injections, and no sedation were needed.
Severe early childhood caries means widespread, active tooth decay in a child under age 6. It is one of the most common chronic diseases of childhood, and the standard fix has often meant a trip to the operating room. Small children usually cannot sit still for a drill, so dentists sedate them or put them under general anesthesia to fill or pull the teeth. That is expensive, hard to schedule, and carries real risk for a one-year-old.
Silver diamine fluoride takes a different approach. It is a liquid that a dentist brushes onto the soft, decayed part of the tooth in seconds. The silver kills the bacteria feeding on the tooth, and the fluoride hardens what is left. The goal is not to rebuild the tooth. The goal is to freeze the decay in place so it stops eating deeper toward the nerve.
What the data show
Researchers randomly assigned 830 US children under age 6 with severe early childhood caries to receive either 38% silver diamine fluoride or a placebo liquid painted onto their active cavities. Neither the families nor the examiners knew which one a child got. The liquid went on at the first visit, and a second coat was applied at the six-month mark.
Six months after that single first application, 54.0% of cavities treated with silver diamine fluoride had stopped progressing, compared with 22.5% of cavities that got the placebo. That is a 31.5 percentage point advantage, or about 315 more stopped cavities for every 1,000 treated. Put another way, a treated cavity was roughly 2.4 times as likely to stop as an untreated one.
The trial was designed to a very strict standard of proof, and the result cleared it. The true benefit is very likely somewhere between 21.5 and 41.6 percentage points (99.9% CI), meaning there is less than about a 1 in 1,000 chance a difference this large came from luck alone. Roughly speaking, about 3 cavities need to be painted for 1 extra cavity to stop that would have kept growing on its own.
Dr. Kumar’s Take
I like this study because it solves a problem that is really about access, not just chemistry. Plenty of families cannot get a small child into an operating room for dental work, and plenty of children cannot tolerate a drill. A treatment that takes seconds, costs little, and can be done in a regular chair changes who gets treated at all.
The tradeoff is honest and visible. Silver diamine fluoride turns the decayed spot permanently black. That is the silver reacting with the tooth, and it does not wash off or fade. On a back molar nobody notices. On a front tooth, a parent will notice every day for years. I would want that conversation to happen before the brush touches the tooth, not after.
I also want to be clear about what this does and does not do. It arrests decay. It does not restore the shape of a broken tooth, and it does not undo damage that has already reached the nerve. A little more than half of treated cavities stopped, which means a real share kept moving and will still need a dentist.
Safety, limits, and what happens next
Side effects were no more common with silver diamine fluoride than with the placebo liquid, which matters because the children enrolled here started at 12 months old, the age group where sedation risk is highest and where dentists have the fewest good options. The authors are careful to note that evidence in children under 3 is still thin, and only 34 of the 830 children were one-year-olds, so the reassurance at the youngest ages rests on a small group.
The main limits are worth holding onto. The headline result is measured at six months, so this tells us about stopping decay in the near term rather than about how those teeth look in five years. Roughly 46% of treated cavities were not arrested, so this is a strong first move and not a guarantee. And because the liquid needs reapplying every six months, the benefit depends on the family coming back.
Practical takeaways
- If your young child has active cavities, ask the dentist directly whether silver diamine fluoride is an option before agreeing to sedation or general anesthesia for fillings.
- Expect the treated spot to turn permanently black, and ask the dentist to show you where the staining will be visible when your child smiles.
- Plan on returning every six months for reapplication, since the trial reapplied the liquid at that interval rather than treating once and stopping.
- Keep brushing with fluoride toothpaste and cutting back on sipped sugary drinks, because arresting one cavity does nothing to prevent the next one.
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FAQs
Does silver diamine fluoride hurt when it is applied?
The application itself involves a small brush and a few seconds of contact with the tooth, with no drilling and no injection, which is why the trial could use it in children as young as one. The liquid has a metallic taste that some children dislike, and dentists usually isolate the tooth and coat the gums with a barrier to keep the liquid off soft tissue. Because nothing is being cut, there is no need for numbing. For a child who panics at the sight of dental equipment, that difference matters more than the chemistry does.
Why does the tooth turn black, and can the stain be removed?
The silver in the liquid reacts with the decayed tooth structure and leaves a dark, permanent mark on the part that was already damaged. Healthy enamel is not stained, so the black area is essentially a map of where the decay was. The stain does not polish or bleach away, though a dentist can sometimes cover a front tooth later with a tooth-colored filling or crown once the child is old enough to tolerate the work. Many families accept the staining on back teeth and think harder about front teeth.
Does this replace fillings and dental surgery for good?
No. In this trial, a little over half of treated cavities stopped progressing at six months, so a meaningful share still needed further care. Silver diamine fluoride is best understood as a way to buy time and halt damage in a child who cannot safely or practically undergo restorative work right now. Teeth that are already broken down, abscessed, or causing pain still need conventional treatment, and a dentist should be the one making that call.
Is it safe to use in a one-year-old?
The trial enrolled children starting at 12 months and found no more side effects with the treatment than with the placebo, which is notable because that is the age at which sedation and general anesthesia carry the most concern. Toddlers this young are also the hardest to treat with traditional dentistry, since they cannot cooperate with a drill for any length of time. Only 34 of the 830 children were one-year-olds, though, and the authors point out that evidence in children under 3 remains limited, so this is encouraging rather than settled.
Bottom Line
In the largest and most rigorous test of this treatment so far, painting 38% silver diamine fluoride onto active cavities stopped 54.0% of them from getting worse in young children with severe early childhood caries, compared with 22.5% for placebo. It required no drill, no needle, and no sedation, and side effects were no more common than with placebo in children enrolled from 12 months of age. The permanent black staining is a real cost, but for families facing the alternative of dental surgery under general anesthesia, a few seconds with a small brush is a serious option worth asking about.
