What causes cavities in kids?
Cavities in kids develop mainly because of frequent sugar intake, poor oral hygiene, too little fluoride and the thinner enamel of baby teeth, and they can largely be prevented.
The causes combine biology, habits and environment. One of the main factors is frequent consumption of sugary foods such as candy, sweetened drinks and snacks, which feed the bacteria in the mouth.
Another major factor is oral hygiene. Many children do not brush thoroughly, or parents do not supervise brushing closely enough. Sometimes too little fluoride toothpaste is used, or a toothpaste without fluoride. The ADA recommends a smear of fluoride toothpaste the size of a grain of rice from the first tooth until age 3, then a pea-size amount from age 3 to 6, with an adult supervising and the child spitting out rather than swallowing. Baby teeth also have thinner enamel than permanent teeth, which makes them more vulnerable to bacteria, and some children develop a hole in a tooth at a very young age.
Heredity can also play a part: some children are born with more vulnerable enamel, or with saliva that offers less natural protection. Another risk factor is the transfer of cavity-causing bacteria from parents to children through shared utensils or kisses on the mouth. Early detection and prevention are the keys to stopping decay from spreading in the baby teeth.
How cavities form in kids' teeth
Cavities form in several stages, starting when certain mouth bacteria, mainly Streptococcus mutans, break down carbohydrates and produce acids. These acids lower the pH in the mouth and start to dissolve minerals (mainly calcium and phosphate) from the enamel, leaving porous areas that can gradually become a rotten tooth.
A white spot on the enamel
The first visible sign is a white spot on the enamel surface, showing that minerals are being lost. At this stage the process can still be reversed: fluoride toothpaste and fluoride products help the enamel take minerals back in.
Decay reaches the dentin
Without treatment, the acids go deeper and reach the dentin. Dentin is softer than enamel and contains tiny tubules leading toward the nerve, so damage here can cause sensitivity and pain.
Decay reaches the pulp
If tooth decay keeps progressing, bacteria can reach the pulp, which holds the nerves and blood vessels of the tooth. Infection of the pulp causes inflammation and severe pain and can lead to an abscess. In children this can happen faster, because the enamel and dentin of baby teeth are thinner.
Between acid attacks, saliva naturally puts minerals back into the enamel. But when teeth are exposed to acid too often, for example through frequent candy or sweet drinks sipped throughout the day, saliva cannot keep up and the cavity progresses.
How are cavities in kids treated?
Treatment depends on how advanced the decay is, the child's age and how well he or she can cooperate. The aim is to treat existing cavities and to prevent new ones at the same time.
Early lesions that have not yet formed a cavity can be treated without drilling, with professional fluoride varnish or gel. Treatment options include:
- Early lesions: professional fluoride treatments
- Advanced decay: tooth-colored composite fillings or stainless steel crowns
- Decay reaching the pulp: pulp treatment adapted to baby teeth
Once decay has formed a cavity, the tooth needs to be restored. In back baby teeth, a composite filling or a preformed stainless steel crown is used, depending on the size of the lesion; stainless steel crowns are a durable option when decay is extensive. In front teeth, tooth-colored options such as composite fillings or pediatric zirconia crowns may be used.
When decay has reached the pulp, the baby tooth needs a form of root canal treatment adapted to children: a pulpotomy (removal of part of the pulp) or a pulpectomy (removal of all of it), depending on the clinical situation. Keeping baby teeth until they fall out naturally helps hold space for the permanent teeth. If a tooth is too damaged to be saved, it is removed and a space maintainer may be considered.
Alongside treatment, parents and children receive guidance on brushing, a diet lower in sugar and the correct use of fluoride products. For children with frequent tooth decay, sealants on the back teeth and more frequent visits may be recommended.
Examination, treatment plan and price quote
detailed and personalized
During the consultation, Dr Haim Aseriel examines your teeth, explains all the options and gives you a transparent price quote, with no obligation. The clinic is at 12 HaTnufa Street, Jerusalem.
Baby bottle tooth decay: why a child should not fall asleep with a bottle
Baby bottle tooth decay is an aggressive form of cavities in the baby teeth of infants and toddlers, caused mainly by long contact with liquids that contain sugar.
It is linked to giving a bottle of sweetened drinks, fruit juice, milk or formula at bedtime or throughout the day to soothe the child. During sleep, saliva flow drops sharply and the liquid stays in contact with the teeth.
The typical pattern affects the upper front baby teeth most, while the lower front teeth are usually protected by the tongue and saliva. Damage can be fast: the first sign is a thin chalky line along the gumline, which can turn brown or black.
Beyond pain and infection, damaged front teeth can affect speech, chewing and the child's self-confidence, and early tooth loss can disturb how the permanent teeth come in. Advanced cases sometimes need extensive treatment under general anesthesia, which the clinic does not perform; this is why treating decay early matters, especially in young children.
Prevention is simple: do not put a child to bed with a bottle of anything other than water. Clean the baby's gums with a damp gauze pad even before the first teeth come in, start gentle brushing as soon as the first tooth appears, and book the first dental visit when the first tooth erupts, no later than the first birthday. According to the American Academy of Pediatric Dentistry (AAPD), children at risk of cavities may also benefit from professionally applied fluoride varnish.
Signs of cavities in kids' teeth
Early detection of cavities in kids is essential to prevent irreversible damage. The first and most common sign is a white or brown spot on the tooth surface. Parents often miss these signs at first, especially on the back teeth or on surfaces that are hard to see.
At a later stage, the child may complain of sensitivity to hot, cold or sweet foods. As decay advances further, spontaneous pain, swelling or even an abscess can appear: at that point, the child should be seen by a dentist promptly. Diagnosis combines a careful visual examination, a digital intraoral scan with the clinic's Shining 3D Aoralscan 3 (no impression paste) and, when needed, dental X-rays to assess how deep the lesion goes.
Signs to watch for:
- a white spot near the gum line
- a brown spot or a hole in the tooth
- sensitivity to sweets or cold
- pain when chewing
- swelling of the gum or cheek
Cavities in baby teeth are not less serious than cavities in permanent teeth: they actually progress faster, because the enamel is thinner.
Restoring, preventing and following up
For early lesions, professional fluoride treatments and protective sealants strengthen the tooth and help remineralize affected areas. Early diagnosis allows a careful, conservative approach that removes as little tooth structure as possible.
Restoring the tooth
When decayed tissue has to be removed, the tooth is rebuilt with a tooth-colored composite suited to children's teeth, as part of a dental restoration that preserves as much healthy tooth as possible. For extensive damage to baby teeth, a preformed crown may be recommended.
Prevention and follow-up plan
Parents and children receive guidance on brushing, flossing adapted to the child's age and diet. Check-ups usually take place every six months, or at an interval based on the child's risk of cavities (AAPD).
For children with dental anxiety, most can be treated under local anesthesia, with explanations beforehand and a pace adapted to the child. The clinic does not perform treatment under general anesthesia; when these measures are not enough, light oral sedation may be considered, on prescription and at the dentist's discretion.
Israeli health basket: children and teenagers up to age 18 are entitled to dental care under the national health basket, through their health fund (kupat cholim). Preventive care is free; fillings, root canal treatment and extractions involve a co-payment, at the health fund's clinics or clinics that have an agreement with it. Check your eligibility with your health fund.
How to prevent cavities in kids
Most cavities in kids can be prevented with a few daily habits and regular visits.
- Brush twice a day with fluoride toothpaste: a rice-grain smear until age 3, a pea-size amount from 3 to 6, with an adult supervising (ADA).
- Limit sugar between meals: candy, juice and sweet drinks sipped throughout the day are the main culprits.
- No bottle in bed: only water if the child needs a bottle to fall asleep.
- Avoid sharing spoons: and do not "clean" a pacifier in your own mouth.
- Start dental visits early: by the first birthday, then usually every six months or as recommended.
- Ask about sealants: they protect the grooves of the back teeth.
Consultations at the clinic, at 12 HaTnufa Street in south Jerusalem, can be held in English; read more about children's dental care at the clinic.
Cavities in kids: frequently asked questions
Cavities in kids are caused by mouth bacteria that turn sugars into acids, which gradually dissolve the enamel of the teeth. The main risk factors are frequent sugary snacks and drinks, brushing that is irregular or unsupervised, too little fluoride, and the thinner enamel of baby teeth. Bacteria can also pass from parent to child through shared spoons or kisses on the mouth.
Baby bottle tooth decay is an aggressive form of cavities in the baby teeth of infants and toddlers, caused mainly by long contact with sugary liquids, especially when a child falls asleep with a bottle. Saliva flow drops during sleep, so the liquid stays on the teeth. A child should not be put to bed with a bottle of anything other than water.
The first sign of cavities in kids' teeth is usually a white or brown spot on the tooth surface, which shows that the enamel is losing minerals. Later, the child may be sensitive to hot, cold or sweet foods. If decay keeps progressing, spontaneous pain, swelling or an abscess can appear, and the child should be seen by a dentist promptly.
No. Cavities in baby teeth are not less serious than cavities in permanent teeth. They can actually progress faster, because the enamel and dentin of baby teeth are thinner. Untreated decay in a baby tooth can cause pain, infection and early tooth loss, which can affect how the permanent teeth come in.
To prevent cavities in kids, brush twice a day with fluoride toothpaste from the first tooth (a rice-grain smear until age 3, a pea-size amount from 3 to 6), limit sugary snacks and drinks between meals, never put a child to bed with a sugary bottle, and start dental visits by the first birthday. Sealants on the back teeth add protection.
Yes. Children and teenagers up to age 18 are entitled to dental care under the national health basket (sal habriut), through their health fund (kupat cholim). Preventive care, such as a periodic check-up, oral hygiene instruction, scaling and sealants, is free. Conservative treatment, such as fillings, pulp treatment (including root canal) and extractions, involves a co-payment. Care is given at clinics of the health fund or at clinics that have an agreement with it, and private treatment outside the health fund is not reimbursed. Check the details of your eligibility with your health fund.
Sources
- American Academy of Pediatric Dentistry, Policy on Early Childhood Caries (ECC): Consequences and Preventive Strategies, 2025 – View source
- American Academy of Pediatric Dentistry, Periodicity of Examination, Preventive Dental Services, 2022 – View source
- ADA Council on Scientific Affairs, Journal of the American Dental Association, 2014 – View source
- American Academy of Pediatric Dentistry, Behavior Guidance for the Pediatric Dental Patient – View source
- Kol Zchut, Dental care for children and teenagers in the health basket (Hebrew), 2026 – View source
