What to Know About Silver Diamine Fluoride (SDF) for Dental Care

Medically Reviewed by Robert Brennan on September 06, 2023
Written by WebMD Editorial Contributors
3 min read

Silver diamine fluoride (SDF) is a clear liquid that can be used to help prevent cavities from growing, particularly in children.

By combining fluoride’s ability to remineralize teeth with silver’s antibacterial properties, SDF can strengthen your teeth and prevent cavities from growing and spreading to other teeth. Read on to learn more about SDF, its benefits and risks, and more.

SDF is a liquid that dentists use to help prevent cavities from growing and spreading. 

This dental treatment can be used on people who don't want to or can’t get traditional restorative treatment, such as children and people with special needs. Typically, it’s used on children aged two to eight. ‌

SDF is a popular method of treating children’s cavities because:

  • It is inexpensive.
  • It doesn’t require the dentist to actually remove cavities.
  • It can be reapplied after two to four weeks at the back of the mouth
  • It's easy to apply

The fluoride in SDF boosts tooth strength by remineralizing the enamel, or top layer of your teeth. Meanwhile, the silver in SDF kills the bacteria responsible for wearing your teeth down.

In addition to treating children’s cavities, SDF can also treat tooth sensitivity in adults. It does so by strengthening your dentin, which is the sensitive part of the tooth that is under the enamel. 

SDF is applied to your teeth in the following way:

  1. Cotton is placed near the teeth to keep them dry.
  2. A vacuum is used to remove moisture.
  3. A microbrush is used to apply SDF to the cavity on the tooth. The area is then rubbed for one minute.
  4. The tooth is then air-dried.
  5. Light curing is used to make sure SDF sinks deeper into the tooth.

Your dentist doesn’t have to fill your cavities or modify your tooth surface before using SDF since SDF is strong enough to stop and prevent most cavities by itself.

There are many benefits to using SDF.

Effective and efficient.  SDF is a common choice amongst dentists because of its effectiveness. A study has shown that it can stop around 80% of cavities and can be applied in less than a minute.

Compared to other treatments, SDF’s ability to stop cavities is 89% higher over a 12-month period.‌

Safe. Many studies and trials have shown that there are no serious side effects other than staining. ‌

Quick and painless. Unlike traditional treatments such as filling a cavity, SDF is quick and painless. As such, it may be a great choice for children, particularly very young children with situational anxiety. ‌

It may also be a good choice for some people with special needs such as intellectual and developmental disabilities.

Ability to prevent cavities. Not only does SDF prevent your cavities from spreading or getting larger, but it can also prevent future cavities from developing.

Inexpensive. SDF is relatively inexpensive, although there’s a wide range of prices. On average, one application of SDF costs around $75, averaging from $20 to $25 per tooth. Depending on what state you’re from, SDF might also be covered under Medicaid.

SDF is safe to use. In fact, it has less fluoride than one application of fluoride varnish, which is also often used to prevent cavities.‌

In general, SDF only has the following side effects:

  • Gum irritation, although this usually goes away within a couple of days
  • Metallic taste in your mouth
  • Low prevalence of gum and tooth pain
  • Irreversible dark stains in the areas where it’s applied, particularly on cavities. Gums and other parts of the mouth can get stained as well, although these stains will eventually go away, unlike the stains on your teeth. SDF can also temporarily stain skin and clothes that come in contact with the solution.‌

A study has suggested that nano silver fluoride (NSF) may be a preferable alternative to SDF, since it works like SDF without staining. However, more research may have to be done in this area, since NSF is a relatively new treatment compared with SDF.

You should avoid using SDF if you have:

  • Silver allergy
  • Lesions or tooth decay that’s opened up the soft tissue inside your tooth (pulp), since using SDF can make the infection spread to surrounding areas.‌

Make sure to talk to your dentist about your medical history and what you expect from SDF before you decide to use it. If you’re not comfortable with the idea of you or your child developing irreversible dark stains in the areas where SDF is applied, it may not be for you.