Silver diamine fluoride

Silver diamine fluoride, or SDF, is a liquid painted directly onto an area of active decay to stop, or arrest, its progression, without the drilling or anesthesia a conventional restoration usually requires. A systematic review of 16 clinical trials found it arrested roughly 81% of active carious lesions in primary teeth, and a large randomized trial following nearly 3,000 children found it noninferior to glass-ionomer sealants for preventing new caries over two years: genuinely strong evidence for a remarkably simple intervention.

The FDA has cleared SDF only for treating tooth sensitivity, the same category as fluoride varnish, which makes its use for arresting caries technically off-label: legal and well-supported by the evidence, but worth naming explicitly in informed consent rather than assuming every patient already understands that distinction.

It permanently darkens the arrested carious dentin (not sound enamel), which is a real esthetic tradeoff in visible areas: addressed with the SMART technique, covering the arrested lesion with glass ionomer to restore form and mask the stain. It is especially useful for young children, elderly patients with root caries, and anyone who cannot tolerate conventional restorative treatment.