When thumb sucking or pacifier use continues past age three, it can push the front teeth forward, create an open bite and narrow the upper jaw. The age of stopping matters most.
Thumb sucking and pacifier use start to affect tooth position and jaw growth when they continue past age three. The usual results are upper front teeth pushed forward, an open bite where the front teeth no longer meet, and a narrowed upper arch. Stopping around age three gives the best chance of spontaneous correction.
Why sucking has such an effect
Tooth position is set by a balance of forces: lips and cheeks pushing in, the tongue pushing out. A thumb or pacifier disturbs that balance. Duration matters more than strength. Brief sucking a few times a day rarely leaves a trace, while hours of sucking through the night applies a constant gentle force that slowly moves teeth and shapes growing bone.
What can change
- Upper front teeth tipping forward, making lip closure harder
- An open bite where front teeth do not touch
- A narrow upper arch from cheek muscle pressure during sucking
- Crossbite in the back segments
- Speech changes, especially with s and z sounds
Thumb or pacifier?
Both work through the same mechanism. A pacifier is usually easier to give up because it is an object you can control; a thumb is always available and often appears at bedtime or in moments of stress. What matters orthodontically is how many hours a day the habit lasts and at what age it ends.
When it should stop
Sucking is normal in infancy. The aim is for it to fade by two and end around three. A habit still present after four deserves an orthodontic assessment, and one continuing past seven, when the permanent incisors erupt, is much less likely to self correct, making orthodontic treatment more likely.
What helps children stop
- Positive reinforcement such as charts and stickers rather than shaming
- Noticing the triggers and offering an alternative in those moments
- Changing the bedtime routine so hands stay occupied
- Stopping in stages, daytime first and night time later
- Habit breaking appliances when the dentist considers them necessary
An open bite often closes on its own once the habit ends early, but a narrowed upper jaw usually needs an expansion appliance while growth is still available. An early assessment keeps future treatment smaller in scope. Paediatric dental and orthodontic assessments are available at our Muratpaşa clinic at any hour, seven days a week.
