Fluorosis
White or brownish spots on the teeth that won’t go away despite good oral hygiene – for many patients, the diagnosis of “fluorosis” comes as a surprise. Fluoride has been considered an essential protection against cavities for decades, yet excessive fluoride intake during childhood can produce the opposite of what was intended: permanent changes in the tooth enamel. This article explains how fluorosis develops, how to recognise it, and what treatment options are available.
What is fluorosis?
Fluorosis is a developmental disorder of the tooth enamel caused by excessive fluoride intake during tooth formation in childhood. It is neither a disease in the classical sense nor a sign of poor oral hygiene.
What is fluorosis – and how does it develop?
Fluorosis develops when children absorb too much fluoride during the phase of tooth development – from birth to around the age of eight. During this sensitive phase, fluoride affects the function of ameloblasts, the cells responsible for forming tooth enamel. An overdose disrupts this process, causing the enamel to become porous, unevenly mineralised, or discoloured. The result is whitish, yellowish, or in severe cases brownish spots on the teeth.
Important to understand: The changes occur silently during tooth formation beneath the gums. They only become visible when the affected teeth erupt.
Fluorosis vs. chalky teeth (MIH) – what's the difference?
Fluorosis and chalky teeth (molar-incisor hypomineralisation, or MIH) are frequently confused, as both lead to white or yellowish-brown discolouration of the tooth enamel. The key difference lies in the cause and appearance:
- Fluorosis usually affects multiple teeth symmetrically and presents as diffuse, whitish lines or spots. It is painless and alters the tooth structure visually, not functionally.
- Chalky teeth (MIH) typically affect the first permanent molars and/or the incisors, often asymmetrically. The enamel is soft, brittle, and the affected teeth can be very sensitive or painful. MIH has different causes – presumably systemic factors such as illnesses or medications during early childhood.
An accurate diagnosis by a dentist is important, as the treatment approaches differ.
Fluorosis or cavities – how to tell the spots apart
Cavities can also cause white or brown spots, which may lead to confusion. If you notice yellow teeth despite brushing, various causes may be responsible – including both fluorosis and cavities.
- Fluorosis spots are usually smooth, symmetrically distributed, and often located on the chewing surfaces or the upper area of the tooth crown. They are already present when the tooth erupts.
- Cavity spots develop over time, usually in areas that are difficult to clean (interdental spaces, fissures). They may become increasingly dark and are often accompanied by a soft, porous tooth structure.
In case of doubt, a dental examination should always be carried out.
Recognising fluorosis spots: symptoms and appearance
The appearance of fluorosis varies considerably – depending on the severity of the overexposure and the time at which it occurred. Some people notice only fine, barely visible white lines, while others show clearly visible discolouration or even structural changes to the enamel. A careful assessment of the symptoms helps determine the severity and select the appropriate treatment.
White spots, brown spots – the different severity levels
The severity levels of fluorosis are commonly classified using the Dean’s Index:
- Questionable / Very mild: Fine white lines or small white spots that are barely noticeable. Affecting less than 25% of the tooth surface.
- Mild: White, opaque spots on more than 25% of the tooth surface. Tooth structure intact.
- Moderate: Distinct white to yellowish-brown discolouration across most of the tooth surface.
- Severe: Brown spots, pit-like indentations in the enamel (pitting), structural damage to the enamel. This form is rare and only occurs with very high fluoride exposure.
Fluorosis in primary teeth and permanent teeth
Fluorosis can affect both primary teeth and permanent teeth – depending on which developmental phase the overexposure occurred in. Since primary teeth are already mineralised during pregnancy and in the first months of life, excessive fluoride intake by the mother or baby during this time can theoretically also affect the primary teeth. However, permanent teeth are more commonly affected, as their development continues into school age.
Fluorosis in children, toddlers, and babies
Fluorosis in children usually results from a combination of different fluoride sources: fluoride-containing children’s toothpaste, fluoride tablets, fluoridated table salt, and in some regions also drinking water. The risk is particularly high when toddlers swallow toothpaste, as they have not yet reliably mastered spitting out. For this reason, professional associations recommend using only a rice-grain-sized amount of children’s toothpaste for toddlers.
Fluorosis in adults – can it still occur?
No – classical dental fluorosis cannot newly develop in adults, as tooth development is complete. What becomes visible in adults are fluorosis changes that developed during childhood and only became apparent with the eruption of the permanent teeth. Skeletal fluorosis – a fluoride overexposure affecting the bones – is a separate issue and is generally only relevant in regions with extremely high natural fluoride levels in drinking water.
Causes of fluorosis
Fluorosis occurs when the body absorbs more fluoride during tooth development than the enamel can process. The sources are varied—ranging from toothpaste and dietary supplements to drinking water. What matters is not a single source, but the total amount of fluoride a child consumes each day.
Too much fluoride in childhood – but how much is too much?
Fluoride in low doses is an effective protection against cavities – this is well supported by scientific evidence. At the same time, as with many substances, the right dosage is what matters. Chronically excessive fluoride intake during the tooth development phase leads to fluorosis. The recommended daily dose varies depending on age, body weight, and existing fluoride sources in the diet.
The tricky part: Fluoride comes from many sources simultaneously – toothpaste, fluoride tablets, fluoridated table salt, drinking water, and certain foods. If these sources are not coordinated, cumulative overexposure can occur without being consciously noticed.
Fluorosis from toothpaste, fluoride tablets, or drinking water
The most common causes of fluorosis in Switzerland and Germany are:
- Fluoride-containing children's toothpaste: If too much toothpaste is used or regularly swallowed, fluoride intake increases significantly.
- Fluoride tablets: If these are given in addition to fluoridated table salt and fluoride-containing toothpaste, overexposure easily occurs.
- Fluoridated table salt: Widely used in Switzerland – those who use it should be cautious with other fluoride sources.
- Drinking water: In most Swiss regions, the natural fluoride content of drinking water is low. In other countries (e.g. parts of India or Africa), however, it can be very high.
Which toothpaste is suitable – and which is not?
The question of the right toothpaste – with or without fluoride – is now the subject of a broader societal discussion. On one hand, the caries-preventive effect of fluoride is well established in dentistry and supported by numerous studies. On the other hand, more and more patients are consciously choosing fluoride-free alternatives – for personal, ecological, or health-related reasons.
This decision ultimately lies with each patient. What is clear, however, is that those who forgo fluoride must ensure caries protection by other means. Without effective protection, the risk of cavities increases – especially in children.
Possible alternatives for caries protection without fluoride:
- Hydroxyapatite toothpaste: A mineral active ingredient that is structurally very similar to natural tooth enamel. Some studies show a comparable remineralising effect to fluoride – the evidence is promising but not yet as extensive as for fluoride.
- Oil pulling: Daily Oil pulling with coconut or sesame oil is a traditional method from Ayurvedic medicine. It can help reduce bacteria in the oral cavity and support the gums. However, as a sole means of caries protection, it is not sufficiently supported by evidence.
- Mouthwashes with oxygen-containing molecules: Oxygen-based mouthwashes (e.g. with activated oxygen or chlorine dioxide) can effectively reduce anaerobic bacteria – those that thrive without oxygen and promote cavities and periodontitis.
- Essential oils: Mouthwashes or toothpastes containing essential oils such as tea tree oil, peppermint, or clove oil have proven antibacterial properties and can positively influence the oral flora.
- Dietary adjustment: A low-sugar, alkaline-rich diet is one of the most effective measures for caries prevention – regardless of whether fluoride is used or not.
- Regular dental hygiene: Regardless of the choice of toothpaste, professional dental hygiene remains one of the most important pillars of dental health.
Which combination is right for you or your child should be decided individually and in consultation with your dentist.
Removing fluorosis spots: treatment options
Depending on the severity of the fluorosis, various treatment options are available – from minimally invasive to restorative solutions. The most suitable method depends on the extent of discolouration, the condition of the tooth enamel, and the patient’s individual needs. After a thorough examination, your dentist can recommend the appropriate therapy.
Icon treatment for fluorosis
The Icon treatment (infiltration) is a minimally invasive method that achieves particularly good results for mild to moderate fluorosis spots. A low-viscosity resin is infiltrated into the porous tooth enamel, filling the microstructure and normalising the light refraction of the tooth – the white spots are thereby significantly reduced visually or disappear entirely.
The major advantage: no tooth substance is removed. The treatment is painless, usually takes only one session, and is also suitable for children. Icon is particularly effective for white fluorosis spots – for brown or structurally damaged spots, the results are more limited.
Bleaching for fluorosis – useful or not?
Bleaching for fluorosis is a widely discussed topic. In some cases – particularly with mild fluorosis and a yellowish base discolouration – professional bleaching can help lighten the overall colour of the tooth and make the spots less noticeable.
At the same time, there are cases where bleaching initially makes the white spots more prominent, as the surrounding enamel becomes lighter while the fluorosis spots react differently. Whether bleaching is appropriate for fluorosis must therefore always be decided individually and after a thorough diagnosis. A combination of bleaching followed by Icon treatment is often recommended.
Composite veneers and ceramics for pronounced fluorosis
For moderate to severe fluorosis with structural damage to the enamel or pronounced brown discolouration, restorative solutions are often the most effective option:
- Ceramic veneers: For permanently beautiful results in severe fluorosis. Colour-stable, biocompatible, and long-lasting – however irreversible, as a small amount of tooth enamel must be removed.
- Composite veneers: Directly applied composite material covers the discolouration and restores the aesthetics of the tooth. Minimally invasive, reversible, and possible in a single session.
Med. dent. Ayleen Haase
Would you like to know whether your tooth discolouration is fluorosis? Book an appointment for a no-obligation consultation.
Frequently asked questions about fluorosis
Fluorosis raises many questions – from how it develops to how to recognise it and how to treat it. We have compiled the most common answers here for you.
No, fluorosis does not go away on its own – since the change in the tooth enamel is structural in nature, it persists without treatment. However, with the right treatment methods such as Icon treatment, bleaching, or veneers, the spots can be significantly reduced visually or completely covered.
Home remedies such as baking soda, lemon juice, or activated charcoal can slightly reduce superficial discolouration but have no effect on the structural changes in the tooth enamel caused by fluorosis. Moreover, aggressive home remedies can further damage the enamel. Their use is therefore not recommended.
For children who already have fluorosis, further fluoride intake should be carefully reviewed and reduced if necessary. Whether a fluoride-free toothpaste – such as one based on hydroxyapatite – is appropriate should be discussed individually with the dentist. The key is to ensure adequate caries protection through other means.
Dental fluorosis in mild to moderate form is primarily a cosmetic issue and does not pose a health risk. In severe fluorosis, structural damage to the tooth enamel can occur, making the tooth more susceptible to abrasion and cavities. Early diagnosis and treatment is therefore recommended.
The first step is a dental examination to assess the severity of the fluorosis and recommend the appropriate treatment. Depending on the findings, minimally invasive methods such as Icon treatment, bleaching, or – for more pronounced cases – veneers may be considered. At the same time, it is worth reviewing current fluoride sources in daily life to avoid further overexposure.
Further information
Here, you can find additional information on the topic to gain a deeper insight.