August 21, 2026, 11:01 am | Read time: 6 minutes
Another cavity! Tooth decay is one of the most common health issues in childhood, and the usual treatment is often anything but pleasant for the little ones. Yet, cavities can generally be well prevented. But what if damage has already occurred? A new study shows that silver diamine fluoride could help stop even severe forms of cavities in young children—all without drilling. FITBOOK looks at the results of the current study.
Why Cavities Were of Interest for the Study
Common cavities usually result from a combination of bacteria in the mouth, frequent sugar consumption, and inadequate oral hygiene. Additionally, genetic predisposition can significantly influence personal risk. There is also a particularly severe form: “severe early childhood caries” (S-ECC) or severe early childhood cavities. It can cause pain and infections and, in the worst case, lead to tooth loss. Sometimes, it requires extensive dental treatments under general anesthesia.
A study led by researchers from the University of Michigan examined whether existing deep cavity lesions in baby teeth could be stopped using a relatively gentle treatment method.1 The focus was on those affected by the described severe early childhood cavities—and 38 percent silver diamine fluoride (SDF), simply known as silver diamine fluoride.
Silver Diamine Fluoride Against Cavities in Children
Silver diamine fluoride is not a new invention. The active ingredient has been used for decades to halt cavities, in the form of a liquid applied to the affected tooth surface. Silver diamine fluoride can promote the remineralization of tooth substance and inhibit the activity of microorganisms. However, a visible side effect is a characteristic dark discoloration of the treated cavities.
The effectiveness of SDF has been investigated in various studies. For example, a study with Chinese preschool children showed that 38 percent SDF can help stop existing cavities in the dentin.2
The current U.S. study specifically examined the effectiveness of SDF in young children with severe early childhood cavities. It provides further data for the use of the method. So far, cavity treatment with silver diamine fluoride has not been approved by the U.S. Food and Drug Administration (FDA).
Details of the Study
The study was a randomized, blinded, and placebo-controlled Phase III trial. This means that participants were randomly assigned to two treatment groups. Neither they nor the researchers knew who received which treatment.
Initially, 830 generally healthy children participated in the study, though not all completed it; more on that later. One group (consisting of 414 children) received the silver diamine fluoride under investigation, while the other (416 children) received a seemingly identical treatment with a placebo. The tinctures were applied at the start and after six months, without removing the cavities beforehand. The lesions were cleaned, dried, and treated for about 10 seconds. The study ran from October 2018 to April 2023, with an observation period of about eight months per child. In total, researchers examined around 2,000 cavity lesions, 976 in the SDF group and 1,011 in the comparison group.
Examinations took place at the start and after three, six, and eight months. The researchers focused less on the color of the lesions and more on whether the diseased tooth tissue had hardened. This is a sign that the tooth substance is reabsorbing minerals and stopping its dissolution. They used a standardized system to assess cavities. Additionally, they determined whether patients experienced pain and/or other adverse events. The statistical analysis considered that a child could have multiple treated lesions.
Silver Diamine Fluoride Stops Cavities More Often Than Placebo
The results clearly favor 38 percent SDF, as they showed a noticeable difference between the two groups. After six months—the predetermined primary endpoint of the study—54.0 percent of the cavity lesions in the SDF group had stopped progressing. In the placebo group, it was 22.5 percent. After just three months, the arrest rate in the SDF group was higher. There, 57.5 percent of the lesions had stopped, compared to 18.8 percent in the placebo group.
After six months, a second application was made, but this apparently did not lead to further improvement in arrest rates. The next examination, eight months after the study began, showed that 50.2 percent of the lesions in the SDF group had stopped, compared to 17.4 percent in the placebo group.
Did the treatment affect the extent of pain? In this regard, the researchers have no significant advantages of silver diamine fluoride on cavities to report. There was no statistically significant difference between the groups at any of the examined time points. A similar picture emerged with side effects: At least one adverse event was observed in 47.3 percent of children under SDF and 43.3 percent of children in the placebo group. Most complaints were mild to moderate.
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Significance of the Results
For evaluating the result, it is crucial to define “cavity arrest”: The disease is not necessarily eliminated. In the study, a lesion was considered arrested if the affected tooth tissue had hardened. After six months, this was the case for 54.0 percent of the SDF lesions. Many lesions remained active. The authors emphasize that SDF should not be seen as the sole measure for children at high risk of cavities.
Cavities Partially Stopped Even Without SDF
It should also be noted that the study does not show an absolute treatment effect but initially only allows a comparison with a placebo. Even in the placebo group, 22.5 percent of the lesions had stopped after six months. Some cavities can spontaneously stabilize without SDF.
Why SDF Can Still Be Interesting for Young Children
In any case, the study provides important clinical data for a treatment that can be applied without drilling and without prior removal of cavities. Especially for very young children with severe cavities, such a non-invasive approach can be relevant.
For further research, other application intervals, the treatment of non-collapsed cavities, and possible preventive effects are relevant. The authors already see the results as an important basis for further examination of an FDA approval of SDF for cavity treatment in children with S-ECC.
Limitations
A factor that significantly limits the reliability of the results is the high percentage of participants (around 30 percent) who did not complete the study. The timing of data collection, which coincided with the COVID-19 pandemic, was the reason. The authors therefore used an intention-to-treat analysis and statistical methods to handle missing data.
Overall, the study duration of eight months per child was too short to assess long-term effects. The sample was diverse but did not represent all children in the U.S. The study also focused on already collapsed cavity lesions in children with particularly high cavity risk. The significance of the potential of a silver diamine fluoride treatment for children with ordinary cavities is overall limited.