Thumb Sucking: Will it Affect My Child's Teeth?

Will thumb sucking affect my child’s teeth?  

Thumb sucking is comforting for young babies. But as children grow the habit can cause problems that may need to be corrected later in life.  

How thumb sucking impacts your child’s teeth 

Most children will stop sucking their thumb between the ages of two and four. Thumb sucking beyond this age can cause problems with how your child’s mouth develops. Kids mouths are very malleable and constant pressure from on the roof of the mouth can cause: 

• A crossbite - where the upper and lower teeth are misaligned 
• The central lower incisors to lean too far outward 
• The lower lateral incisors to lean too far inward 
• The roof of the mouth to become heavily arched or form a v shape 
• The upper front teeth to form an overbite   

Thumb sucking can cause bite problems, make it harder for your child to clean between their teeth and often results in kids needing braces or orthodontics in their teens. 

What age does thumb sucking become a problem? 

Thumb sucking is less of a concern for baby teeth, but it can make a difference once a child’s permanent teeth erupt. Thumb sucking can negatively impact a child's teeth from five or six years old.  

According to Orthodontics New Zealand it only takes light pressure to move teeth, if your child is sucking their thumb for long enough. It only takes around six hours for thumb pressure to start moving teeth.  

How common is it for children to suck their thumb? 

Thumb sucking is a fairly common behaviour. Around one in three babies suck their thumbs but most children naturally give up the habit between the ages of two and four. Surprisingly, around one in 20 children will continue to suck their thumb by the age of eight. At this age, it will affect how their teeth and mouth develop.  

How can I prevent changes to my child’s teeth? 

Protecting your child’s teeth starts with regular dental visits. Once your child is six months old, or has their first tooth, it’s time for them to start seeing a children’s dentist. Here, you can talk through any concerns, like their thumb sucking habit, as your child grows.  

As well as this, there are some things you can do to discourage your child from thumb sucking like: 

An oral device 

In some cases, a thumb crib can be fitted on older children who struggle to stop sucking their thumb. It consists of a metal grid positioned behind the upper teeth. The metal device serves as a physical reminder and blocks access to the back of the teeth and roof of the mouth – where your child wants to put their thumb.   

At-home devices 

Before a thumb crib is fitted, some parents try out at-home devices. Placing a plaster on their child’s thumb or using a bitter-tasting nail application (usually used to stop nail biting) can act as a reminder for your child to break the habit.  

Removing the thumb as they sleep 

If your child sucks their thumb while they are asleep you can also try gently removing it from their mouth.  

What happens if my child develops misaligned teeth 

If your child sucks their thumb, they might need orthodontics to fix their bite issues. The best age for braces is between ten and fourteen. At this age their adult teeth have grown in, but their teeth are very responsive to change. The catch is your child will need to stop this habit before they can have treatment.  

If your child or teen is still sucking their thumb, it will stop the braces from working effectively. Even after their braces are removed, continued thumb sucking can cause the teeth to shift again. 

If your child has ongoing problems with thumb sucking, you should raise these with your dentist. 

At Gentle Dental, we can help you and your child develop healthy habits for the life of their teeth. Book an appointment to see one of our friendly dentists today.