The link between tooth decay in milk teeth and the alignment of permanent teeth

Many parents view tooth decay in children as a minor issue, on the basis that ‘baby teeth will fall out anyway’. In reality, the health of baby teeth is essential for the proper development of permanent teeth, and parents must take care of their children’s baby teeth to prevent tooth decay.

Cavities in milk teeth can cause pain, infections, difficulty chewing and even speech problems. Furthermore, leaving them untreated can directly affect the correct alignment of permanent teeth and may lead to the need for complex orthodontic treatment in the future.

In this article, we explain the importance of baby teeth for your child’s long-term health, the consequences of tooth decay in baby teeth, and what steps should be taken to prevent tooth decay in children. 

There is a very close link between the health of milk teeth and the permanent dentition: the early loss of a milk tooth or the development of infections can directly influence how the permanent tooth erupts and aligns.

It is important to emphasise that milk teeth are not merely ‘temporary teeth’, and their role is crucial for:  

• Chewing – teeth allow the child to chew properly and enjoy a varied diet
• Speech – they support proper language development; early tooth loss can lead to pronunciation difficulties, particularly with certain consonants such as (S, T, D)
• Appearance and mental well-being – a child with decayed or missing teeth may become shy and avoid smiling.

However, the most important role of milk teeth is to act as a ‘guide’ for the permanent teeth. They maintain the space needed for eruption and guide correct alignment. If a milk tooth is lost too early, the neighbouring teeth tend to drift into the empty space, thereby reducing or even eliminating the space that should have been maintained for the permanent tooth. This phenomenon can lead to dental crowding, malocclusion and even bite problems. Bite problems lead to imbalances in the temporomandibular joint, the joint that allows the jaw to move. If dental crowding or misalignment occurs, the temporomandibular joint will suffer, and the child may experience pain or difficulty closing or opening their mouth. 

Baby teeth are more vulnerable than permanent teeth: the enamel is thinner and more porous, and the dentine is less resistant. For this reason, tooth decay in children progresses much more rapidly. 

The main risk factors include frequent consumption of sweet foods and sugary drinks, poor oral hygiene, the habit of falling asleep with a bottle of milk or juice, and the transmission of cavity-causing bacteria from parents.

Failure to treat baby teeth leads to a cascade of events, all of which are harmful and have long-term implications. An untreated cavity does not ‘wait’ for the tooth to fall out; it can quickly, within just 1–2 months, lead to:

• pain and infections (dental abscesses)
• premature tooth loss
• damage to the bud of the permanent tooth located beneath the root of the baby tooth
• chewing and nutritional problems  
• the development of dental fears and anxiety in the child. 

When a milk tooth is extracted prematurely due to advanced tooth decay, the space left behind may be taken up by neighbouring teeth. Without this ‘natural guide’, the permanent tooth that is due to erupt no longer has its normal place and will appear crooked or crowded.

This migration of the temporary teeth creates spatial imbalances, and the child may subsequently require braces. Sometimes, the loss of a single milk molar can affect the entire dental arch.

Infections caused by deep caries can reach the buds of the permanent teeth, and the consequences can range from the eruption of a permanent tooth with enamel defects—which can decay very easily—to delayed or blocked eruption. 

To protect your child’s smile, it is essential to establish an oral care routine from an early age. Once their first teeth appear, it is a good idea to start brushing twice a day, in the morning and in the evening. Use a soft toothbrush suitable for your child’s age and a very small amount of fluoride toothpaste (about the size of a grain of rice).  

For older children, the amount can be increased to the size of a pea. Until the age of 6–7, a child’s motor coordination is not sufficiently developed to brush effectively, so it is crucial that parents get actively involved and help them to ensure that all teeth are cleaned properly.

A balanced diet and reducing sugar intake are also vital for preventing dental problems.

Tips for a healthy diet:

• avoiding frequent sweet snacks
• replace fizzy drinks with water  
• encourage the consumption of crunchy fruit and vegetables.

Regular visits to the dentist and preventive treatments, such as fluoride treatments and sealants, play an equally important role in preventing dental problems. Regular check-ups, carried out at intervals of no more than 6 months, as well as the first visit to a paediatric dentist no later than 6 months after the first tooth erupts, serve to detect any potential tooth decay whilst it is still very small and can be treated or stopped from progressing. 

1. Lam PPY, Chu CH, Lo ECM. Association of Early Childhood Caries and Caries Increment in Permanent Dentition: A Meta-analysis. Front Public Health. 2022.
2. Songur F, Simsek Derelioglu S, Yilmaz Ş, Ceyhan D. Caries experience in primary teeth and permanent first molars. Eur J Paediatr Dent. 2019.
3. Wikipedia – Early Childhood Caries
4. Parents.com – The surprising truth about cavities