Is Fluoride Varnish Enough?

Discover the Benefits of Fluoride Varnish:
A Powerful Dental Treatment for Stronger Teeth & Enhanced Oral Health

By: Candy Velez – CRDH, BSDH

As a clinical dental hygienist with a decade of experience, I have rarely heard patients ask the question, “Is Fluoride Varnish enough to protect my teeth?”

Instead, patients often ask questions like:

  • “Do I really need a fluoride treatment?”
  • “Do I need to have a fluoride treatment at each hygiene visit?”
  • “Can I skip the fluoride treatment this time?”

In addition, patients often say, “I do not need a professional fluoride treatment because I already use fluoride at home.”

However, as dental professionals, it is crucial to shift our focus to a different question:

“Is fluoride varnish alone enough to protect a patient’s teeth against tooth decay?”

To answer this question, we must first understand what fluoride varnish is and understand fluoride’s role in protecting tooth enamel.

What is Fluoride Varnish?

Fluoride varnish is a dental treatment that involves applying a concentrated fluoride solution onto the surfaces of teeth.

Fluoride varnish creates a thin protective coating. Once placed on the patient’s teeth, the varnish adheres to the tooth enamel, delivering a high concentration of fluoride that strengthens the crystalline structure of tooth enamel.

Most Fluoride Varnishes Have Three Main Ingredients:

  1. Sodium Fluoride
  2. Ethanol
  3. Synthetic Resin or Shellac

How Does Fluoride Strengthen Tooth Enamel?

Fluoride strengthens tooth enamel through a process called remineralization.

When fluoride is applied to teeth, it interacts with the minerals in the tooth, specifically hydroxyapatite, which is the primary component of enamel.

When fluoride is absorbed by the tooth, it attracts calcium and phosphate ions from saliva. The fluoride, calcium, and phosphate ions combine to form a stronger mineral called fluorapatite. 

Fluorapatite is more resistant to acid attacks and less soluble than hydroxyapatite.

Did you catch that…fluoride attracts calcium and phosphate from saliva and other sources to create fluorapatite.

Therefore, patients will have more protection from tooth decay when the saliva is supersaturated with calcium and phosphate.

When prescribing fluoride varnish, are you assessing the quality and quantity of a patient’s saliva?

The Important Role of Saliva in Tooth Remineralization

Saliva can be referred to as the body’s true mouthguard.

The truth is, when the teeth are strengthened with fluoride and saliva is saturated with calcium, phosphate, and bicarbonate, the teeth will be protected, even if acids are introduced into the mouth.

As dental professionals, we have been taught that there is a critical pH value (approximately 5.5) when tooth demineralization occurs.

However, demineralization occurs when the solubility product quotient of saliva falls below the tooth’s mineral solvent threshold.

In chemistry, this is referred to as the (Qsp) of the aqueous solution falling below the (Ksp) of the mineral.

Therefore, there is not a specific pH number that is critical; rather, it is a certain ratio between the strength of teeth and the solution the teeth are submersed in (saliva).  

What Factors Compromise the Quality and Quantity of Saliva? 

Several factors can compromise the quality and quantity of saliva.

Here are some common factors that can affect saliva production and its composition:

  1. Dehydration: Insufficient water intake can lead to dehydration, decreasing saliva production and resulting in a dry mouth. For these patients, I recommend electrolyte supplements to help with better hydration.  
  2. Medications: Certain medications, such as antihistamines, decongestants, antidepressants, and some blood pressure medications, can cause a dry mouth. According to the American Academy of Oral Medicine: “Over 1,100 medications, either prescription or over the counter, have the potential to cause dry mouth.” As a patient’s medication list grows, so does the severity of dry mouth.
  3. Aging: Saliva production tends to decrease with age, leading to a drier mouth in older adults.
  4. Medical conditions: Certain medical conditions like Sjogren’s syndrome, diabetes, autoimmune disorders like Rheumatoid Arthritis, HIV/AIDS, and Parkinson’s disease can affect saliva production.
  5. Radiation therapy: Radiation treatment for head and neck cancer can damage the salivary glands, decreasing saliva production and causing dry mouth.
  6. Nerve damage: Injury or damage to the nerves that control salivary glands can impair saliva production.
  7. Smoking and alcohol consumption: Tobacco smoking and excessive alcohol consumption can negatively affect saliva production and composition.
  8. Stress and anxiety: Psychological factors like stress and anxiety can lead to a decrease in saliva production.
  9. Poor oral hygiene: Neglecting proper oral hygiene practices can lead to oral health issues, including reduced saliva production.
  10. Salivary gland disorders: Certain conditions, such as salivary gland stones, infections, or tumors, can affect saliva production.

Is Fluoride Varnish Enough? 

In my practice as a dental hygienist, the answer is, no.

Fluoride varnish is not enough to protect the many patients I treat. Most of my patients receive a professional fluoride varnish treatment on their teeth every three months, and they receive a take-home product with bioavailable calcium and phosphate.

Why? In my practice, I treat many elderly patients with complex medical histories who take prescription drugs. Those prescription drugs contribute to dry mouth, leading to compromised saliva. 

Many products can help elevate the calcium and phosphate levels in saliva; some can be purchased online, while others can be carried in the dental office.

The next time a patient asks you if a professional fluoride varnish treatment is necessary, ask yourself if a fluoride varnish treatment is enough for your patient’s specific oral conditions.

If that patient is of moderate to high caries risk and has compromised saliva, not only will they benefit from a professional fluoride varnish treatment, but they may also require a take-home product to help supersaturate their saliva with the minerals necessary to allow the fluoride varnish treatment to work at its best. 

🦷 Access Your Free Caries Risk Assessment Documents Here.


Photo by Karolina Grabowska

Candy Velez - CRDH, BSDH

Candy Velez - CRDH, BSDH

Candy Velez is an active professional member of the American Dental Hygienists' Association (ADHA) and serves as the Highlands County Representative for the Atlantic Coast Dental Hygienists' Association (ACDHA). In addition, she maintains membership with The American Academy for Oral Systemic Health (AAOSH). In addition to practicing clinically, Candy currently serves on the Florida Board of Dentistry's Council on Dental Hygiene, and she was the recipient of the Swann D. Knowles Award in 2020. The Swan D. Knowles Award honors one hygienist from the state of Florida for their grassroots efforts in service and dedication to the dental hygiene profession.