Fluoride Varnish

Fluoride application is a preventive treatment that leaves a high concentration of fluoride on the tooth surface for a short time. With children, the form we use most is fluoride varnish: a thin layer painted onto the teeth with a small brush, which sets on contact with saliva and stays on the surface for hours. The aim is to make enamel more resistant before decay starts, and to halt decay that has begun but has not yet formed a cavity.

What does fluoride do for teeth?

Enamel loses minerals to the acid produced after sugary food and drinks, and wins some of them back thanks to saliva. Fluoride tips this cycle towards gain: as minerals return, it helps a more acid-resistant structure form on the surface, and it somewhat slows the production of acid by the bacteria in plaque. Chalky white spots along the gum line are the first sign that this balance has tipped the wrong way; at this stage, regular fluoride and good brushing can often stop the decay. Once a cavity has formed, however, fluoride alone is not enough, and baby tooth treatment or a filling is needed.

How is the varnish applied?

1. Plaque is cleaned off the teeth with a brush or gauze.
2. The teeth are briefly dried with cotton.
3. The varnish is painted in a thin layer over all surfaces with a small brush.
4. It sets on contact with saliva; there is no rinsing.

The whole procedure takes a few minutes. There is no numbing, no drilling and no scraping; what your child feels is a slightly sticky coating on the teeth and, with some varnishes, a fruity taste. That is why this is the procedure through which many children first get used to the dental chair. Older children are sometimes given a gel in a mouth tray instead of varnish. Varnish is preferred at a young age because it works with a very small amount, so the quantity swallowed stays low.

With babies and very young children we often do the application with your child on your lap: they sit facing you, with their head resting on the dentist's knees. That way they can still see you, and the dentist has a clear view of the teeth. A short explanation at home beforehand, something like "We're going to paint on a polish that makes your teeth stronger", helps the first dental experience go calmly.

How often is it needed, and who needs it?

The frequency is set by your child's decay risk, not by the calendar.

Situation	Typical interval
A child with no decay who brushes regularly and has sugar only occasionally	Twice a year; sometimes less often is enough
A child who has had decay recently or has white spots	Every 3–4 months
A child wearing braces, with a dry mouth, or whose teeth are hard to brush	More often, at an interval set by the dentist

No single factor decides the risk: how often sugary food and drinks are had through the day, how regularly the teeth are brushed, any previous decay and active decay in the family are all weighed together. If the risk is high, fluoride on its own is not the answer; it is tackled together with eating habits and how often your child is seen for check-ups.

Fluoride is not just for children. It is also used to prevent white spots forming around the brackets in teenagers wearing braces, to protect exposed root surfaces in adults, and to reduce tooth sensitivity.

Is a professional dose of fluoride safe?

This is the question parents ask most, and it is a fair one. The concentration of fluoride in varnish is high, but the total amount used in one application is very small, and because it sticks to the teeth most of it is not swallowed. Fluorosis, which leaves white flecks on the teeth, is linked to taking in too much fluoride over months and years while the teeth are developing, for example by swallowing toothpaste every day, not to varnish applied a few times a year.

There are exceptions you should know about. For children who are allergic to colophony (pine resin), which some varnishes contain, or who have widespread sores in the mouth, a different product is chosen or the application is postponed; tell us about any allergies beforehand. Fluoride tablets or drops, on the other hand, should not be given without a dentist's assessment; before deciding on a supplement like this, your child's drinking water, the toothpaste they use and their decay risk need to be considered together.

What can your child eat afterwards, and when can they brush?

• Ideally, nothing to eat or drink for the first half hour.
• For the rest of the day, give soft, lukewarm food; hot drinks and hard or crunchy food take the varnish off early.
• Do not brush the teeth that evening. Normal brushing the next morning removes what is left of the varnish.
• The teeth may look yellowish or dull for a few hours; that is the varnish itself, and the colour of the teeth does not change.

How much fluoride toothpaste should your child use at home?

Professional application does not replace daily brushing at home; it complements it. The general guide is:

• From the first tooth to age 3: a smear of fluoride toothpaste the size of a grain of rice, spread thinly over the teeth.
• Ages 3–6: a pea-sized amount.
• From age 6: your child can move on to adult toothpaste, as your dentist advises.

After brushing, your child spits the toothpaste out but does not rinse with lots of water, so the fluoride stays on the surface. Until the age of seven or eight, an adult needs to finish off the brushing. Because the deep grooves on the chewing surfaces of the molars cannot be fully protected by brushing and fluoride, fissure sealants are the natural complement to fluoride. At our clinic in İzmir we often plan both for the same check-up appointment.