Major study confirms simple liquid can stop cavities without drilling

How the treatment works

Dentists apply silver diamine fluoride, or SDF, directly to a cavity with a small sponge-tipped applicator. The process takes seconds per tooth and does not require drilling, injections or sedation.

Silver helps fight bacteria linked to decay, while fluoride strengthens tooth minerals and helps resist further damage. The treatment arrests decay, meaning it stops worsening, but does not replace tooth structure lost to the cavity.

Why another option matters

Thousands of young children in the United States go to emergency departments each year for untreated cavities. Emergency physicians generally cannot perform the dental procedures needed to address the cause, and some children eventually need surgery under general anesthesia. Conventional treatment can also be difficult for children who cannot stay still or feel fear and anxiety.

Tradeoffs and broader use

SDF permanently darkens the decayed part of a treated tooth, which can be especially noticeable on front teeth. The discoloration is mainly cosmetic, but it may affect whether families choose the treatment.

Dentists have used SDF to manage cavities in numerous countries for decades. In the United States, the FDA approved it as a medical device for tooth sensitivity in 2014; dentists also use it off-label to stop cavities. The trial adds large-scale evidence from U.S. participants on its safety and effectiveness for decay.

University of Michigan dentistry professor and lead investigator Margherita Fontana said the treatment is effective and safe, including for children as young as 1. She also identified older adults, people with disabilities, people with severe dental anxiety, and those who have difficulty accessing conventional care as potential beneficiaries.