How do thumb sucking and dummy use affect children’s teeth?

One of the most common questions and concerns among parents of young children is how to break an oral habit that involves thumb-sucking or using a dummy. Sucking is a natural reflex, and infants develop these habits in the womb. Hence, they immediately know how to suck on the breast or bottle once born. Sucking is normal, soothing, and intuitive for our little ones and provides a sense of security and relaxation. However, prolonged exposure to sucking has the potential to affect how your child’s mouth grows and develops, as well as how their teeth align with each other.

Recognising and understanding the timing and effects around these non-nutritive oral habits is essential for us to reinforce when to intervene and when to let it be. 

How do thumb sucking and dummy use affect children’s teeth?

When is it time to intervene?

Do you notice your child requesting a dummy or sucking on their fingers, thumb, or even another object such as a blanket at certain times of the day or during particular situations? If so, this is common and normal! Because sucking is therapeutic, you may notice your child desiring their dummy or finger at naps or at bedtime, or even during times of stress or insecurity, such as being in a new environment or with unfamiliar faces. According to research,  most children break these habits between ages 2-4 without any intervention or damage to the development of their mouths or teeth. Past the age of four is a good time for parents to start investigating the habit more. The Australian Dental Association is a great source for dental information:

How to break oral habits?

Dummy use tends to be an easier habit to break when compared to sucking on a finger(s) because you can simply take it away. Some dental providers will argue that taking it away too soon may result in your child replacing the dummy with a finger to mimic the habit, creating more challenges. You cannot take a finger away, so be mindful of the approach and timing of eliminating the dummy.

  • Reduce exposure time
  • Talk about it
  • Create motivation
  • Positive reinforcement

  •  If your child uses a dummy all day long or for long periods, consider reducing the amount of time your child can have their dummy and give only when you feel it is necessary (such as sleeping). You may also consider having a conversation around the dummy if your child is old enough to understand new concepts. Maybe there is a younger sibling in the home, and you claim they need it more than your oldest. Creating a motive may also help your child move past desiring a dummy. A form of internal motivation to quit something is more likely to be successful than just taking it away. Lastly, promote positive reinforcement. When you notice your child not requiring a dummy, provide an abundance of praise. Children love to hear when they do something well versus being told they cannot have something. The Grin Kids Brushing Challenge sticker chart is also a fun way to provide extra motivation and praise for breaking an oral habit. Add an additional sticker to the day if you notice your little one taking a big step in kicking the habit to the curb! 

    The thumb/finger-sucking habit is a bit more tricky to break because it goes everywhere with your little one. Similarly to dummy use, notice when your child is sucking on their finger/thumb the most and understand what drives them towards the habit. Thumb/finger-sucking may be a consistent habit or very dependent on the child’s situation where it provides comfort and a form of security. 

  • Create distraction 
  • Investigate the motive and what triggers the habit
  • Explain the importance in breaking the habit
  • Praise, praise, praise

  • By creating distraction around the habit, your child may quickly learn of other ways to fill that void of needing to suck on their finger/thumb. Offer a hug, favourite stuffed animal, or gentle words. If your child is feeling anxious and notice this triggering the habit, look for ways to correct the problem or talk about their feelings to understand why they are feeling the way they do. You may also want to set small goals with your child that include them in the process. This can create internal motivation and success.  Again, this is dependent on the age and where your child is in their development. Past the age of four is when the habit may become more problematic to the development of their mouth and teeth.  If the bulleted methods above are not working, you may consider covering the finger of choice with a bandage or sock to help remind your child not to suck. 

    What are the oral complications associated with oral habits?

    Much of the oral complications associated with dummy use and thumb/finger-sucking is dependent on the frequency and force of sucking. For example, a child who rests their dummy or finger in their mouth without truly sucking will be less affected by the oral effects than a child who sucks more aggressively. This is because the sucking habit changes the way their palate is affected or how the teeth align.


  • Changes in the roof of the mouth (narrow and higher arched palate)
  • Affects how teeth come together (tooth alignment and how your child bites together)
  • Germs with potential risks for illnesses 
  • How do thumb sucking and dummy use affect children’s teeth?

    Registered dental hygienist, Sarah Liebkemann (instagram: @sll.stories), designed this graphic to show what an anterior open bite looks like and how prolonged exposure to sucking on a dummy or finger may affect how teeth align. In this photo, the front teeth do not touch when biting down. This is because the palate has become arched and more narrow. 

    Breaking these oral habits before your child begins to lose their baby teeth allows for more time for correction before the permanent teeth begin to erupt. The longer the habit and the more vigorous sucking may lead to more challenging ways of correcting tooth alignment and changes the bite. If the habit continues past the age of four and into when permanent teeth begin erupting, your dentist may recommend an oral appliance to help stop the habit and begin adjusting their bite or roof of the mouth. 

    Your dental provider can also serve as a helpful resource in providing ways to help break your child’s oral habit. Some kids may even respond better if someone outside of the home is encouraging them to stop and may offer a special reward if they break the habit independently. Be sure to have this conversation with your child’s dentist at their next checkup if you are concerned or have other questions. 

    About the Author

    Kristen Cockrell, RDH 

    All graphic images created by Sarah Liebkemann, RDH @sll.stories

    Photo by Kyle Nieber and Martin Dubé on Unsplash