Preventing tooth decay in children and teenagers

Photo of a mother and child brushing their teeth

Tooth decay, also known as dental cavities or caries, is the most common dental problem amongst children. It can cause painful holes (cavities) in your teeth. Cavities usually need to be drilled and then filled to keep the tooth decay from getting worse. But doing certain things can help to prevent the need for treatment in the first place.

The most effective way to prevent tooth decay is by regularly brushing your teeth and strengthening them with . Pediatricians and dentists recommend already giving babies tablets with vitamin D starting at the age of one week. Once the first milk tooth comes in, toothpaste can be used instead.

It is also just as important to stick to a healthy diet and not have sugary foods or drinks too often. Last but not least, dental check-ups can help to detect and treat tooth decay early on.

What foods and drinks make a difference?

Tooth decay is mainly caused by bacteria in the plaque that coats your teeth, and by too much sugar in your diet. So limiting your consumption of sugary foods, drinks, candies and other sweets is one way to prevent tooth decay. Eating sweet things sometimes is perfectly fine, though, as long as you still take good care of your teeth.

The trouble starts when teeth are frequently exposed to sugary foods and drinks. Babies and toddlers may develop tooth decay faster if their bottle often contains sugary drinks or fruit juice. Unsweetened fruit teas or water are good alternatives. It's also important to use the bottle only for drinking and not as a pacifier or dummy.

Using salt with when cooking and seasoning your food also helps to strengthen your teeth. Experts recommend that young children also eat fluoridated salt as soon as they start having regular meals with the rest of the family.

What should you know about brushing teeth?

Brushing your teeth gets rid of plaque and keeps your teeth looking and feeling clean. Fluoride toothpaste is especially good at helping to prevent tooth decay: Your teeth absorb the in the toothpaste, making them stronger.

Research has shown that brushing with toothpaste every day can help prevent tooth decay in children and teenagers. Children need adults to show them how to brush properly, and very young children need hands-on help. Even if a preschool child is able to brush their teeth, an adult may need to help by touching up afterwards. If you're not sure how to go about it, you can get some practical advice from your dentist. Children generally start to brush their teeth properly on their own after they start school, around the time they can write well. It is important to brush the teeth thoroughly but also carefully, to avoid damaging the gums.

Fluoride tablets or fluoride toothpaste?

Pediatricians and dentists recommend already starting to give children tablets at the age of one week. These tablets also contain vitamin D to prevent rickets. Parents can start brushing once the first baby tooth comes in.

Before the child turns one year old, parents should only do one of these two things: either give the baby tablets or use toothpaste. If you give your child tablets, then don't use toothpaste to brush their teeth.

These are the recommendations on the use of toothpaste and tablets, depending on the age of the child:

Child's age Fluoride toothpaste or tablets Amount / Frequency
From the age of one week until the first tooth comes in Fluoride tablets with vitamin D
From the time the first tooth comes in until the child's first birthday
Fluoride tablets with vitamin D
Fluoride toothpaste with 1,000 ppm (0.1%)
  • The size of a grain of rice
  • Twice daily
From the age of one to two years Fluoride toothpaste with 1,000 ppm (0.1%)
  • The size of a grain of rice
  • Twice daily
From the age of two to six years Fluoride toothpaste with 1,000 ppm (0.1%)
  • The size of a pea
  • Two times a day at home and once at daycare

The reason why different doses (size of a grain or rice or of a pea) are recommended is because of the possible side effects: Too much can cause white spots or stripes to form on the teeth as they develop. But it doesn’t usually have any other negative effects. In rare cases, too much can affect the development of the tooth enamel, increasing the risk of tooth decay. Whitish spots can also be an early sign of tooth decay.

It is especially important to get the dose right in young children under the age of two years, because they often swallow their toothpaste. So it's advisable to not use additional tablets if they use toothpaste and if salt with added is also used at home.

Older children and teenagers can brush their teeth like adults.

Dental floss, interdental brushes and mouthwash

In order to prevent the gums from becoming inflamed (gingivitis), it may be a good idea to remove plaque that forms between your teeth by using dental floss, interdental brushes, dental care sticks (also called interdental sticks or dental floss sticks, sometimes made of bamboo) or toothpicks.

These things haven’t been proven to prevent tooth decay, though. It is important to be careful when removing plaque, because it’s easy to hurt your gums with floss, interdental brushes, or toothpicks.

Mouthwash is another commonly used dental hygiene product. Some types of mouthwash contain . Regularly rinsing with mouthwashes can effectively prevent tooth decay too.

Mouthwash, interdental brushes, dental sticks and toothpicks are only options for older children and teenagers, though. Younger children can’t use them properly, and may swallow mouthwash.

How effective are fluoride varnishes and gels?

To prevent tooth decay, can be applied directly to the teeth in the form of a varnish or gel. Fluoride gel is also available from pharmacies without a prescription and can be put on once a week. Most gels are applied once a week – it's best to check the package insert to see exactly how they are used and for which ages they are suitable. They should be left on the teeth for a few minutes and then spat out. Fluoride varnishes contain a higher concentration of . They are a applied by a dentist or dental assistant and harden immediately when they make contact with saliva. This is a particular advantage in toddlers because they don't have to spit out the varnish after a certain amount of time. Varnishes and gels can't replace regular tooth brushing or a tooth-friendly diet, though.

Research suggests that varnish can prevent tooth decay in baby teeth better than regular dental care (without any special use of ). Permanent teeth can also benefit from the use of varnishes or gels.

In Germany, statutory health insurers cover the costs of varnishing

  • four times a year between the ages of 6 months and six years, and
  • twice a year between the ages of 6 years and 18 years (or four times a year if there's a greater risk of tooth decay).

Up to the age of twelve years, children can take part in group prevention programs at day care and in schools. This involves a dentist coming in to check their teeth and mouth, see how their bite is developing and offer varnish to harden the dental enamel. Permission from the parents is needed before any is applied. This treatment is offered free of charge. But it may not be necessary if the child is already having regular varnish treatments at the dentist.

What is a dental sealant and when is it an option?

Children's back teeth (molars) are particularly prone to tooth decay. Bacteria can settle in the fissures, grooves and pits of these teeth. In children who have teeth that are prone to decay, the dentist can put a plastic sealant on the molars in order to stop from growing there. Applying the sealant doesn’t hurt or take very long, and it can lower the risk of tooth decay. Sealants usually last for several years. The dentist will check whether they are still intact during check-ups. In Germany, statutory health insurers cover the costs of this treatment on the permanent back teeth (molars) of children between the ages of 6 and 17 years.

How often should you go to the dentist for a check-up?

In Germany, children who are covered by statutory health insurance are eligible for dental check-ups from an early age. A total of six dental tests are offered between the ages of 6 months and 6 years. After that, it's still a good idea for the child to go in for a check-up every six months.

If any of the standard childhood check-ups (in U5, U6 or U7) show anything abnormal on the child's teeth or in their mouth, their dentist can take a closer look.

Some experts believe that regular dental check-ups can help to detect tooth problems earlier, leading to faster treatment. These check-ups also aim to help children and teenagers to take better care of their teeth and gums. But so far, studies have not shown that having a check-up every six months is better for your overall dental health.

Ahovuo-Saloranta A, Forss H, Walsh T et al. Pit and fissure sealants for preventing dental decay in permanent teeth. Cochrane Database Syst Rev 2017; (7): CD001830.

Arora A, Kumbargere Nagraj S, Khattri S et al. School dental screening programmes for oral health. Cochrane Database Syst Rev 2022; (7): CD012595.

Bundeszentrum für Ernährung (BZfE). Kariesprävention im Säuglings- und frühen Kindesalter. (Handlungsempfehlungen des bundesweiten Netzwerks Gesund ins Leben). 2023.

Chou R, Pappas M, Dana T et al. Screening and Interventions to Prevent Dental Caries in Children Younger Than Age Five Years: A Systematic Review for the U.S. Preventive Services Task Force. (AHRQ Evidence Syntheses; No. 210). 2021.

Davidson KW, Barry MJ, Mangione CM et al. Screening and Interventions to Prevent Dental Caries in Children Younger Than 5 Years: US Preventive Services Task Force Recommendation Statement. JAMA 2021; 326(21): 2172-2178.

Deutsche Gesellschaft für Präventivzahnmedizin (DGPZM). Empfehlungen für Kinderzahnpasten mit Fluorid. 2021.

Deutsche Gesellschaft für Zahn-, Mund- und Kieferheilkunde (DGZMK). Fluoridierungsmaßnahmen zur Kariesprophylaxe (S2k-Leitlinie, in Überarbeitung). AWMF-Registernr.: 083-001. 2013.

Deutsche Gesellschaft für Zahnerhaltung (DGZ), Deutsche Gesellschaft für Zahn-, Mund- und Kieferheilkunde (DGZMK). Kariesprophylaxe bei bleibenden Zähnen - grundlegende Empfehlungen (S2k-Leitlinie, in Überarbeitung). AWMF-Registernr.: 083-021. 2016.

Fee PA, Riley P, Worthington HV et al. Recall intervals for oral health in primary care patients. Cochrane Database Syst Rev 2020; (10): CD004346.

Gemeinsamer Bundesausschuss (G-BA). Beschluss des G-BA über die Richtlinien des Bundesausschusses der Zahnärzte und Krankenkassen über die Früherkennungsuntersuchungen auf Zahn-, Mund- und Kieferkrankheiten (zahnärztliche Früherkennung gemäß § 26 Absatz 1 Satz 2 des Fünften Buches Sozialgesetzbuch – SGB V): Neufassung. 2019.

Gemeinsamer Bundesausschuss (G-BA). Richtlinien des Bundesausschusses der Zahnärzte und Krankenkassen über Maßnahmen zur Verhütung von Zahnerkrankungen (Individualprophylaxe). 2003.

Institute for Quality and Efficiency in Health Care (IQWiG, Germany). Application of fluoride varnish on milk teeth to prevent the development and progression of initial caries or new carious lesions: Rapid Report; Commission N17-03. 2018.

Kashbour W, Gupta P, Worthington HV et al. Pit and fissure sealants versus fluoride varnishes for preventing dental decay in the permanent teeth of children and adolescents. Cochrane Database Syst Rev 2020; (11): CD003067.

Marinho VC, Chong LY, Worthington HV et al. Fluoride mouthrinses for preventing dental caries in children and adolescents. Cochrane Database Syst Rev 2016; (7): CD002284.

Marinho VC, Higgin JP, Logan S et al. Topical fluoride (toothpastes, mouthrinses, gels or varnishes) for preventing dental caries in children and adolescents. Cochrane Database Syst Rev 2003; (4): CD002782.

Marinho VC, Worthington HV, Walsh T et al. Fluoride varnishes for preventing dental caries in children and adolescents. Cochrane Database Syst Rev 2013; (7): CD002279.

Mickenautsch S, Yengopal V. Caries-Preventive Effect of High-Viscosity Glass Ionomer and Resin-Based Fissure Sealants on Permanent Teeth: A Systematic Review of Clinical Trials. PLoS One 2016; 11(1): e0146512.

Neusser S, Krauth C, Hussein R et al. Molarenversiegelung als Kariesprophylaxe bei Kindern und Jugendlichen mit hohem Kariesrisiko. (Schriftenreihe Health Technology Assessment (HTA); No. 132). 2014.

Robert Koch-Institut (RKI), Bundeszentrale für gesundheitliche Aufklärung (BZgA). Mundhygiene und Kariesprophylaxe. In: Erkennen – Bewerten – Handeln: Zur Gesundheit von Kindern und Jugendlichen in Deutschland. Berlin: RKI; 2008. S. 83-91.

Walsh T, Worthington HV, Glenny AM et al. Fluoride toothpastes of different concentrations for preventing dental caries. Cochrane Database Syst Rev 2019; (3): CD007868.

Wong MC, Glenny AM, Tsang BW et al. Topical fluoride as a cause of dental fluorosis in children. Cochrane Database Syst Rev 2010; (1): CD007693.

Worthington HV, MacDonald L, Poklepovic PT et al. Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling periodontal diseases and dental caries. Cochrane Database Syst Rev 2019; (4): CD012018.

Wright JT, Tampi MP, Graham L et al. Sealants for Preventing and Arresting Pit-and-fissure Occlusal Caries in Primary and Permanent Molars. Pediatr Dent 2016; 38(4): 282-308.

IQWiG health information is written with the aim of helping people understand the advantages and disadvantages of the main treatment options and health care services.

Because IQWiG is a German institute, some of the information provided here is specific to the German health care system. The suitability of any of the described options in an individual case can be determined by talking to a doctor. can provide support for talks with doctors and other medical professionals, but cannot replace them. We do not offer individual consultations.

Our information is based on the results of good-quality studies. It is written by a team of health care professionals, scientists and editors, and reviewed by external experts. You can find a detailed description of how our health information is produced and updated in our methods.

Comment on this page

What would you like to share with us?

We welcome any feedback and ideas - either via our form or by We will review, but not publish, your ratings and comments. Your information will of course be treated confidentially. Fields marked with an asterisk (*) are required fields.

Please note that we do not provide individual advice on matters of health. You can read about where to find help and support in Germany in our information “How can I find self-help groups and information centers?

Über diese Seite

Updated on September 5, 2023

Next planned update: 2026


Institute for Quality and Efficiency in Health Care (IQWiG, Germany)

How we keep you informed

Follow us on Twitter or subscribe to our newsletter or newsfeed. You can find all of our films online on YouTube.