Your dentist painted something on your child's teeth that turned the cavities black. That's silver diamine fluoride — a highly effective caries arrest treatment. Here's why they used it and what to know.
What Is Silver Diamine Fluoride?
Silver diamine fluoride — SDF — is a liquid treatment painted directly onto cavities. It contains silver, which kills bacteria, and fluoride, which helps strengthen the remaining enamel. The combination is remarkably effective at stopping decay in its tracks.
It's been used in Japan and Australia for decades. It's now gaining popularity in the UK as a gentle, non-invasive way to manage early childhood caries.
Why Did My Child's Teeth Go Black?
When SDF comes into contact with decay, it reacts with the damaged tooth structure. The silver particles oxidise and turn dark — almost black. This is completely normal and expected.
The discoloration is a sign that the treatment is working. The bacteria have been killed and the decay is arrested. In baby teeth, this staining is often considered an acceptable trade-off for avoiding more invasive treatment.
If the cosmetic appearance is a concern, your dentist can discuss options like placing a filling over the treated area to cover the dark stain.
Is SDF Safe for Children?
Yes. SDF has been extensively studied and is considered very safe. The concentration used in dentistry is low, and only a tiny amount is applied to each tooth.
It has been approved for use in children as young as 12 months old in some countries. Side effects are rare and usually limited to temporary staining of the gums or lips, which fades within a few days.
SDF does contain fluoride, but the amount is so small that the risk of fluorosis is minimal — especially when compared to the risk of leaving decay untreated.
When Is SDF a Good Option?
SDF works best on active cavities in baby teeth. It's ideal for very young children who can't tolerate conventional treatment, for anxious patients, or for teeth that are close to falling out naturally.
It's not suitable for teeth with infections at the root tip, or for cavities that are very large and close to the nerve. Your dentist will assess whether SDF is the right choice for your child's specific situation.
The treatment takes just a few minutes per tooth. There's no injection, no drilling, and no discomfort. Your child simply opens their mouth while the dentist paints the liquid on.
Does It Last Forever?
SDF doesn't permanently fill a cavity. It arrests the decay and prevents it from progressing further. The cavity may still be visible, but it shouldn't get any bigger as long as the treatment holds.
Reapplication may be needed every 6 to 12 months, depending on the individual case. Your dentist will monitor the treated teeth at regular check-ups.
SDF is a practical, evidence-based option for managing childhood caries without drama. If your child's dentist has recommended it, it's with good reason.
To discuss whether SDF or other caries management options are right for your child, call 01323 723757 or book at www.meadsdental.com. Meads Village Dental Practice