Under the Thumb

Why do we suck our thumbs?

It is normal for young children to suck on thumbs, fingers and pacifiers as it provides a sense of security, helps them to relax and induces sleep.

Thumb sucking is a very common childhood habit with three quarters of infants sucking their thumb in their first year. Indeed, sucking the thumb is considered normal behaviour for babies and can even start in the womb. Ultrasound scans have observed babies in the womb sucking their thumbs from 28 weeks gestation.

Majority of experts agree that a thumb sucker younger than 5 shouldn’t be pressured to stop. Most children will simply grow out of the habit. However, if it continues once your child starts school, it can have a negative effect on developing teeth and bite. If your child is still sucking his thumb or finger when his adult teeth start to erupt, it really is time to take action to break the habit.

Why is thumb sucking bad for kids?

Persistent thumb sucking can lead to speech problems such as lisping and imprecise pronunciation (especially of Ts and Ds). Once the habit has been stopped natural improvement of the teeth can occur within 6 months. If the habit breaks before the adult dentition becomes established (age 7/8) your child is unlikely to have caused any long term damage to their teeth. Thumb sucking has the following effects on the mouth and teeth:

  • Upper front teeth stick out
  • Narrowing of the upper arch which leads to the development of a crossbite
  • Lower front teeth move inward
  • Anterior open bite where the upper and lower front teeth do not meet

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Does thumb sucking impact my child’s health?

Children with protruding teeth are at a greater risk of suffering from injury and trauma, especially during sports, as their teeth stick out past the lips.

Breaking the habit early may prevent more serious bite problems from developing and could make treatment at a later age shorter and less complicated.

The good news – statistics show that 91% of children stop thumb sucking on their own by the age of 5.

61% of UK’s 10 year old digit suckers have very serious malocclusions (bite problems) compared to those who have never sucked their thumb. In addition to the dental effects, more than 80% of these children suffer speech changes (usually lisps and imprecise pronunciation). And yet if a child breaks his/her habit before the age of 6 or 7 spontaneous improvement of the teeth occurs.