Fluoridation of teeth

Synonym in a broader sense

Fluoride therapy


In dentistry, teeth fluoridation is carried out as a prophylactic measure. Numerous scientific studies have shown that fluoride helps prevent tooth decay.
In dentistry, only low doses of fluorides are used, which are completely harmless to health. The fluoride content in toothpaste is limited to 1500ppm (parts per million). In the case of children's toothpaste, it is reduced to 250 to 500ppm, since children swallow a large part of the toothpaste and, in connection with fluoride tablets, could ingest an excessive dose of fluoride systemically.

How does fluoride work?

Daily acid attacks on tooth enamel occur through food. The enamel is demineralized through demineralization, i.e. Calcium is released from the enamel.
On the other hand, calcium is also re-incorporated from the saliva, this process is called remineralization. As long as demineralization and remineralization balance each other out, no tooth decay will form. Only when remineralization can no longer replace the loss of calcium does caries occur.

Fluorides support the remineralization of saliva and thus help to prevent the spread of tooth decay. The start of decalcification as a result of acid attack does not take place on the surface of the tooth enamel, but directly below it.
As long as the surface has not yet been destroyed, remineralization can prevent a carious defect from breaking out. However, if the surface has already been destroyed, the process can no longer be stopped by remineralization. This promotion of remineralization is a particularly important effect of fluorides.

The second effect of fluorides is the hardening of the tooth enamel by incorporating fluorine ions into the enamel. This increases the fluorine content in the apatite of the enamel, which improves the crystal structure and reduces solubility. Both result in a higher resistance to acid attacks. The tooth enamel hardened in this way cannot easily be attacked by acid. Fluorides have a preventive and repairing effect.

Read more on the topic:

  • Rebuild tooth enamel
  • How does tooth decay occur?

What are the side effects?

When fluoride is used at a therapeutic dose, there are no side effects. However, the situation is different if you use it in too high a dose, which can result in fluoride poisoning. The effects on the teeth are particularly noticeable in children. The permanent teeth can get discolored, which is called fluorosis.

Usually, when there is an excessive intake in childhood, brown stains can later be seen on the teeth. In addition, a tooth damaged by fluoride is no longer as resistant as an undamaged tooth. Too much fluoridation occurs, for example, if the drinking water is fluoridated, a toothpaste containing fluoride is used and fluoride tablets are also administered. You should therefore get this substance, if possible through food or jellies, in order to be able to do without tablets.
If there is an overdose of fluoride externally, whitish stains may appear on the teeth.

In adults, there are no side effects on the teeth, but symptoms of poisoning such as intestinal irritation, vomiting or diarrhea can occur. If these symptoms occur, you should definitely consult a doctor. If you have consumed too much fluoride, a glass of milk can help. The calcium it contains binds the excess fluoride. Please ask the treating pediatrician or dentist about the exact supply quantities.

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Fluorosis of the teeth is a more or less pronounced discoloration of the permanent teeth, less of the milk teeth. The color spectrum ranges from slightly yellowish to brownish. Corrosion can also be present. It is not about damage in the sense of caries, but about irreversible aesthetic changes that can only be remedied by a prosthetic restoration.

The cause is too high a daily dose of more than 2 mg fluoride during the growth phase of the teeth as long as they have not yet erupted. The crucial period is the phase of tooth development in which the tooth germs are still supplied with blood. If teeth are already in the oral cavity, even very high doses of fluoride cannot lead to such changes.

What are fluorides?

Fluorides are fluorine salts made from a compound of fluorine with inorganic or organic elements such as:

  • sodium
  • Calcium
  • Tin or
  • Amine

arise. The salt formation results in completely different properties in contrast to pure fluorine gas. Only these harmless fluorine compounds are used for prophylactic applications in dentistry. The harmlessness of salts made from two very toxic individual substances can best be demonstrated using table salt. It consists of the very poisonous chlorine and the also very poisonous sodium. Together, sodium chloride is formed, i.e. table salt that we consume every day and which is even vital.

Forms of fluoridation

Systemic fluoridation

With systemic fluoridation, the fluoride is supplied to the body by absorption through the gastrointestinal tract. This happens either through food or artificially through taking tablets, fluoridated table salt or also through mineral water.
The fluoride is absorbed into the bloodstream and thus also reaches the salivary glands and the oral cavity. The fluoridation with tablets must be coordinated with children according to age. It should be noted that when children brush their teeth, they either swallow large amounts of toothpaste at will because of its good taste or involuntarily.

Local fluoridation

In contrast to the systemic application, in which the fluoride only reaches the oral cavity in a highly diluted concentration, the local application applies the fluoride directly to the teeth.
The local application is carried out with toothpaste, gel, rinsing solutions or varnishes applied by the dentist. Toothpaste should definitely contain fluoride. Most pastes contain the inorganic sodium fluoride or sodium monofluorophosphate, they are tasteless and get on well with the other ingredients of the toothpaste. In America in particular, toothpaste containing stannous fluoride is also available. Amine fluoride is used as an organic compound in toothpastes.

Another indication for fluorides is the local treatment of sensitive tooth necks.
Usually the neck of the tooth is protected by the enamel and gums. Especially due to periodontal disease, but also due to incorrect tooth brushing, the gums retract and thus expose the tooth neck.

Thermal and chemical stimuli can now be transmitted through the fine dentinal tubules to the pulp and cause pain.
The home application of fluoride gel on the painful tooth neck or the application of fluorine varnish by the dentist seals the open dentinal tubules and thus makes the pain disappear.

Learn more about: Tooth gel

Drinking water fluoridation

The simplest and cheapest way to supply fluoride is to enrich it with fluoride in drinking water. It has already been carried out in America (USA) but also in Europe. The city of Basel in Switzerland and Karl-Marx-Stadt in the former GDR introduced fluoridation of drinking water.
The success was demonstrated in a significant decrease in tooth decay.

In the Federal Republic of Germany, however, there will be no fluoridation of drinking water, as this is viewed as compulsory medication and it would therefore be necessary to provide two separate water pipes for each household so that one can choose between fluoride-free and fluoride-enriched water.

Read more on the topic: Causes of tooth decay

Fluoridation of milk teeth

The fluoridation of milk teeth is a controversial topic. Youth dental care is constantly improving and there is no doubt that fluorides play an essential role in this. However, the scientists are not yet sure which makes more sense:

  • Systemic use: i.e. the intake of fluoride with certain foods or tablets during the maturation phase of the teeth or
  • Local fluoridation: lifelong use of toothpaste containing fluoride or table salt.

However, combining the fluoride with other preventive measures has the best effect:

Constant pacifier and bottle sucking should be avoided, the drinks should be as sugar-free as possible.

A healthy diet also plays an important role. Sufficiently long breaks should be observed between meals.

Oral hygiene of the parents also plays an important role - on the one hand the parents are good role models for the child, on the other hand it has been scientifically proven that children whose mothers developed tooth decay have an increased risk of developing tooth decay themselves.

It should not be forgotten that bacteria are responsible for the development of tooth decay. Therefore, parents should not put their baby's pacifier in their mouth!

What fluoridating agents are there?

There are many different agents and products on the market for fluoridating teeth. First of all, a toothpaste containing fluoride should be used for daily brushing. In almost every commercially available toothpaste, unless otherwise indicated, there is a prescribed amount of fluoride with 1000 to 1500 ppm (= parts per million).
There are also more fluoridated toothpastes or gels that should be used once a week, e.g. elmex gelée (available in the pharmacy). In addition to toothpastes, there are fluoride-containing mouthwashes for daily use. It is also advisable to use fluoridated table salt for cooking. There are also fluoride tablets that can be used for fluoridation.

Read more on the topic: toothpaste

What is a fluoridation splint?

A fluoridation splint is an individual splint made of plastic that serves as a kind of carrier for fluoride-containing gel. It is manufactured in the laboratory to precisely fit the upper or lower jaw and should be worn once a week for about 5 - 10 minutes. Swallowing the gel should be avoided. During production, impressions of the jaws are first made by the dentist and sent to a laboratory. There plaster models of the jaws are created and a custom-fit splint is created on it using a plastic.

It serves an additional fluoridation of the teeth and thus a reduction of the risk of caries. Compared to brushing the fluoride gel onto the teeth, the splint enables a more even distribution over the entire dental arch. Furthermore, the exposure time of the fluoride gel is increased. Since the fluoride gels used contain a dose of approx. 12500 ppm fluoride, use in smaller children is contraindicated. Frequent swallowing of the gel can lead to an overdose of fluoride.

Fluoridation in special cases

Fluoridation of teeth in childhood

The German Academy for Child and Adolescent Medicine recommends that the baby should be given combined fluoride and vitamin D tablets for the first few months.
After the first milk tooth erupts, systemic fluoridation is continued: the body is given 0.25 mg / day of fluoride in the form of tablets or drops until the age of 36 months.

It is combined with vitamin D up to the age of 12 months. After the 36th month of life, systemic fluoridation can be dispensed with if it is ensured that the teeth are brushed (at least) twice a day without the toothpaste being essentially swallowed. In addition, table salt containing fluoride can be used.
If the conditions are not met, it is advisable to continue fluoridation after consulting the dentist.

In contrast to these recommendations, the DGZMK (the German Society for Dentistry, Oral and Maxillofacial Medicine) considers the use of a fluoride-containing toothpaste to be more sensible from the eruption of the first milk tooth. The statement is based on the study results that show that local fluoride supply is more effective and also includes the following points:

  • Fluoridation is not required in the first 6 months of life.

  • When the first milk teeth appear, care should be carried out once a day with a pea-sized amount of fluoride toothpaste. Care should be taken that no large amounts are swallowed.

  • From the 24th month the teeth are brushed twice a day. On the one hand, this should develop good cleaning habits and, on the other hand, strengthen the prevention of tooth decay.

  • The parents should supervise the young children while they are brushing their teeth, if necessary brushing the teeth again.

  • From school age, teeth are brushed with a toothpaste with a fluorine content of 1-1.5 mg.
  • Fluoridated table salt should also be used.
  • The fluoride tablets can be given to children if a fluoride paste or a fluoride-containing salt cannot be used.

Of course, parents often have their own thoughts on how to properly care for their child's teeth. Especially since the children often swallow the dental care products, which are actually cosmetics and are not subject to food controls. The paediatricians recommend avoiding additional table salt in children's food. Therefore local fluoridation cannot take place in this way.

Because of this wide range of information, it is recommended that the first visit to the dentist be at one year of age. Then the dentist can carry out the so-called fluoride anamnesis and ask what measures the parents are taking. People are asked about nutrition because parents often do not know which foods contain fluoride (e.g. black tea). Then the dentist, together with the parents, can decide which measures to take.

Many parents underestimate the important role of deciduous teeth and think, “It's only the deciduous teeth, the permanent ones will follow anyway” - that's a wrong way of thinking!

The milk teeth have an important placeholder function. If a tooth is lost prematurely due to tooth decay, the remaining teeth can migrate into the gap, narrowing the space for the remaining permanent tooth. This can result in a crooked permanent set of teeth and mean costly orthodontic treatment. In addition, inflamed baby tooth roots can endanger the health of the permanent teeth.

The intact milk teeth are a prerequisite for proper nutrition, language learning and emotional development. It should also be remembered that the first permanent tooth erupts at the age of 6. The so-called 6-year-old molar is very often filled or caries at a young age because teeth brushing and fluoridation were neglected.

Sometimes it is too late for prophylaxis - many parents wonder if there is still something left to do. The milk teeth are supplied with plastic or metallic fillings, just like the "adult teeth".

Fluoridation of teeth during pregnancy

Fluoridation of the teeth is also very important during pregnancy.
Especially for women who have to vomit frequently during pregnancy, fluorides are an essential part of dental care. Since many expectant mothers find it difficult to brush their teeth due to the gag irritation, a fluoride-containing mouthwash is recommended. This can be used to rinse several times a day to harden the tooth enamel.

This is a good alternative, especially after vomiting. Correctly brushing your teeth shortly afterwards would damage the tooth enamel, as the tooth surface is softened by the stomach acid and then wears out more quickly when you brush. There is no need to worry about harm to the adolescent. Fluorides are harmless to the child when taken in normal amounts.

Fluoridation of teeth after whitening

Bleaching is a method to whiten teeth again. Strong chemicals are used that attack the tooth enamel. The hardness of the tooth enamel decreases with this treatment, but can increase again due to fluoridation. Applying a fluoride gel is also very helpful during treatment. Hypersensitivity reactions can be reduced and the treatment can be made more pleasant.

Furthermore, the tooth surface roughened by the bleaching becomes smoother again as a result of this measure. Fluoride helps remineralize tooth enamel. This means that minerals are stored back in the teeth and the tooth becomes more resistant. Second, some studies suggest that using fluoridation after bleaching slows down the recurrence of discoloration. In addition, some manufacturers recommend using fluoride gel for two minutes a day after bleaching for about a week to regenerate the damaged tooth enamel.

Read more on the topic: Whitening

Cost of fluoridation

The teeth should be fluoridated weekly.
There are jellies of different brands that are used for this. The best known is Elmex jelly. A small tube of 25g costs about 5 €. Under certain circumstances, you can have a bulk pack issued on a prescription so that only the prescription fee is due in the pharmacy. If you have your teeth fluoridated at the dentist, this is usually done as part of a professional tooth cleaning. The costs vary from doctor to doctor and start at around € 60.


Fluorides are an essential part of caries prophylaxis. They can be used in different dosage forms. They harden the tooth enamel and promote remineralization. In dentistry, they are used in harmless concentrations.
Fluorosis only occurs in the event of an overdose during the development of the teeth, it is harmless to health, but aesthetically disturbing.