Fluoride FAQ

The use of water fluoridation in the prevention of tooth decay is one of Ten Great Public Health Interventions of the 20th Century. In this page, I will explain the importance of fluoride for your teeth, and how it is available in various products.

Fluoride Treatment

As part of your preventative regime every 6 months when you come for your dentist appointment, you will sometimes be given a FLUORIDE TREATMENT in the form of a gel or mouth rinse. Normally, you will need to keep this in your mouth for about a minute, and then spit out. Don’t eat or drink after this treatment for about an hour to help keep the fluoride on the surface of the teeth as long as possible.

However, don’t just depend on your dentist’s fluoride treatment. Brushing your teeth regularly, twice a day, with a fluoride toothpaste is also helpful to prevent decay. Here’s a tip to maximise the use of your toothpaste: After brushing your teeth, spit out the excess toothpaste, but don’t rinse out completely. This leaves a bit of toothpaste in your mouth to continue its work for a bit longer. The fluoride only works when it is in contact with the tooth surface. If it is washed or rinsed away, it loses its effect.

How it works

So, the BIG question is WHY FLUORIDE? The relationship between Fluoride and Teeth was first researched by 2 clever dentists called Dr. Frederick McKay and Dr. GV Black in Colorado Springs, Colorado as far back as 1901. Their research started when Dr McKay noticed that the natives in the area had brown staining (mottling) on their teeth. They finally found that it was significantly correlated to the increased naturally occurring fluoride in the drinking water in the area.

Their research also showed that these people who had ‘mottled teeth’ had a very high resistance to dental decay. This started more research to identify the ideal amount of Fluoride in the water to avoid the mottling BUT also increase the resistance of teeth to decay.

Today, we know that teeth can be more resistant to decay if fluoride is used on:

  1. The developing teeth – The ‘developing’ teeth can utilise Fluoride from the body, i.e. by using INGESTED fluoride while the teeth are still forming. The formation of teeth start at around the 6th week of foetal development up till the age of about 8 years old. However, as mentioned above, too much fluoride increases the risk of forming MOTTLED TEETH (fluorosis).
  2. The existing teeth – The enamel of the (ALREADY FORMED) existing teeth is more resistant if there is is coated with a fluoride-crystal surface. This fluoride-crystal surface is formed when the tooth is exposed to fluoride in the mouth. This is the most widely used method of strengthening your already erupted teeth.

To expand on the second point, fluoride only works when erupted teeth when it is ON the tooth surface. Once it is swallowed or rinsed out, it’s usefulness decreases.

The longer the fluoride mouth rinse or toothpaste is on the teeth, the more effective it will be at preventing decay.

Below are the most common types of products in the market which contain fluoride:

  • Fluoride Toothpaste
  • Fluoride mouthrinses
  • Fluoride Gels/varnishes
  • Water fluoridation
  • Fluoride tablets
  • Fluoride in Salt?!

*It is also important to note that teeth that are ALREADY formed DO NOT become mottled if exposed further to fluoride…it just becomes stronger! AND the body cannot utilised ingested Fluoride if the tooth is already formed.