Preventive Care, Clinical Education

Foam or Varnish: How These Fluoride Methods Stack Up

By Katie Melko, RDH, MSDH on May, 13 2022
Foam or Varnish: How These Fluoride Methods Stack Up
Katie Melko, RDH, MSDH

Katie works as a public health hygienist and educator and as adjunct faculty at Lincoln College of New England. She is involved in ADHA and currently serves as Immediate Past President in Connecticut.

Fluoride is a hot topic and can be quite controversial. Dental professionals often struggle just to get parents and patients to accept a fluoride treatment, never mind then having to decide which type of fluoride is best for that patient.

Let’s talk about fluoride foams and gels versus fluoride varnish and see what makes the most sense for certain clientele. If you’re at one of the many practices that still primarily uses foams and gels, then this article is definitely for you!

So what exactly is fluoride?
According to Mouth, the definition is pretty straightforward:

Fluoride, a naturally-occurring mineral, helps prevent cavities in children and adults by making the outer surface of your teeth (enamel) more resistant to the acid attacks that cause tooth decay.

Fluoride comes in many forms for patients to use over the counter, as well as many forms for professionals to use in the op, including toothpaste, mouthwash, pills, foams, gels and varnish.

Still, I don’t know how many times I’ve heard the following: it’s a toxin, it’s a harsh chemical, it’s unnatural or it causes cancer and brain issues.

When it comes to foams and varnish, how do these two fluoride methods stack up?

The varnish low-down
Varnish is a topical application that’s painted onto the tooth surface with a brush. It takes very little time to apply – about 30 seconds to apply a coating to each tooth surface.. Many varnish formulas adhere to saliva, so teeth don’t need to be dried prior to application. American Dental Association Council on Scientific Affairs states that fluoride-containing varnishes typically contain 5% NaF, which is equivalent to 2.26% or 22,600 ppm fluoride ion. Some varnishes require patients to wait a few hours before eating hard foods and drinking hot beverages after application, but it depends on the brand.

Once varnish is applied, the tooth absorbs the fluoride it needs during the uptake period, which can last several hours (in some cases up to 24 hours). Fluoride varnish isn’t harmful if swallowed because any unused fluoride is secreted through urine.

The American Academy of Pediatrics’ endorses the use of fluoride varnish, telling parents directly:

Fluoride varnish is a dental treatment that can help prevent tooth decay, slow it down, or stop it from getting worse.

Fluoride varnish is safe and used by dentists and doctors all over the world to help prevent tooth decay in children. Only a small amount is used, and hardly any fluoride is swallowed.
Fluoride foams and gels
Foam and gel fluoride applications are put in a foam tray and then the patient will have the fluoride sit on their teeth for 4 minutes. “Commonly used fluoride gels include acidulated phosphate fluoride (APF), which contain 1.23 percent or 12,300 parts per million (ppm) fluoride ion, and 2 percent sodium fluoride (NaF), which contain 0.90 percent or 9,050 ppm fluoride ion.” (NCBI) The patients again are instructed to not eat or drink for at least 30 minutes.

The fluoride uptake has stopped at this point, and fluoride is only being absorbed into the tooth while the tray is on. This product is harmful if swallowed and can cause vomiting and upset stomach. It can only be applied by a trained professional, it comes in many flavors and in gel or foam consistency.

What to choose

Fluoride is a crucial treatment needed for children and adults to help reduce decay and maintain a healthy mouth. We all know that our mouths are connected to our bodies, this treatment has been proven to reduce bacteria. “Beyond the benefit of enhanced remineralization with varnish, it is also ten times as effective at lessening the amount of cariogenic bacteria, S. mutans. Fluoride foam, on the other hand, is less effective at fighting S. mutans than a simple chlorhexidine mouthwash," according to Today’s RDH.

Many offices still use foam or gel simply because the upfront cost compared to varnish is less. But something to consider is the time a clinician saves with the fast applications of varnish. And since gels and foams are packaged in a large bottle it’s easy to use more than you need and have unnecessary waste negating any savings.

Allergies can be a concern when it comes to choosing varnish. Thankfully manufacturers have listened and many varnishes are using synthetic or non-allergenic ingredients in their product. However, it’s always important to check your patient’s medical history and your product information.

“Another potential benefit is the higher concentration of fluoride that varnishes contain when compared to foams,” according to Today’s RDH. All while providing longer protection to the teeth well after their visit. Varnish is less messy and better for gag reflux patients, it is also great for sealing dental tubules for patients with recession, therefore reducing their sensitivity and helping to protect the teeth from root caries.

There is overwhelming evidence that the benefits fluoride offers outweigh foam/gel fluoride treatments. Time management, patient satisfaction, healthier options for patients and ease of use for hygienists are all great reasons to use varnish in your office.


Submit a Comment

Stay up to date