24 Jan Thumb Sucking and Little Teeth: When It’s Normal — and When It’s Time to Act
Thumb and finger sucking are common self-soothing habits in babies and young children — but when they persist, they can start to affect teeth and jaw development. Paediatric dentist Dr Anna Buckeridge explains what’s happening in your child’s mouth, when parents should be concerned, and gentle, practical ways to help children break the habit.
What happens during thumb and/or finger sucking?
Babies have a sucking reflex to establish feeding after they are born. This changes in the first year of life, where thumb sucking becomes more of a self-soothing comforting tool – it is no longer purely about getting nutrition.
During thumb sucking, the tongue thrusts forward, the cheek muscles contract, putting inwards force on the upper jaw, and the ring of muscle underneath the lip tightens and flares around the thumb.
Effects of thumb and/or finger sucking on the face
Baby teeth start to erupt between 6 months and 2 years of age for most children. Then they will start to get front adult teeth around 6 to 8 years of age.
Thumb sucking can have the following effects on either baby or adult teeth, depending on the age of the child.
- Open bite at the front of the mouth: when the back teeth bite together, there is a gap between the top and bottom front teeth
- Flared upper front teeth: this protrusion can also affect the upper jaw as well. The upper tooth positioning makes them more prone to injury
- Tipped back lower front teeth: the teeth are inclined towards the tongue
- Crossbite at the back of the mouth: when the upper and lower teeth meet, the lower teeth are set wider than the upper teeth
- Intrusion: the front teeth appear like they have been pushed upwards into the gum, and only a portion of the top part of the tooth is visible
- Skin irritation: frequent exposure of the skin around the mouth to saliva can cause inflammation
Stopping thumb and/or finger sucking
Breaking any habit is challenging for anyone – child or otherwise! A lot of patience and an encouraging environment is required, because changing behaviour requires consistency and persistence. It is also good to consider why the behaviour is happening in the first place. Thumb sucking is usually just a comforting habit, but it is sometimes a response to a stressful situation or reflective of an underlying anxiety, so it can be useful to discuss thumb sucking habits with the child’s health practitioners or teachers before getting started.
While there can be dental changes in a pre-school aged child with baby teeth, they have limited verbal ability and will find it difficult to understand how current actions have future consequences. At this age, verbal reminders during the day and gently removing thumbs and fingers once asleep will reduce the amount of contact time with the teeth.
For older children, particularly those with adult teeth already, there are some practical tips that may be useful if they are open or keen to stopping thumb sucking. Using a reward chart as a motivator for consistent behaviour, placing band-aids on fingers or wearing gloves to sleep serve as a reminder to avoid thumb sucking.
Deterrent nail polish can work for some children, but if they are determined enough they will suck the nail polish off! If children purposely or inadvertently remove band-aids or gloves, there are tools that stay fixed on the fingers involved (e.g. a thumb guard) or on the teeth (e.g. an anti-habit device) but these are not usually used as a first line strategy. If the adult teeth have been more severely displaced, the child may require orthodontic treatment.
What about dummies/pacifiers?
Similarly to thumbs and fingers, dummies can also become props for children to calm themselves or go to sleep. Dummies vary in material but are usually made of silicone and latex, with a handle that is often made of plastic or wood. Dummies can have similar effects on the mouth to thumbs and fingers, and again the extent of the change is dependent on the contact time the dummy has with the teeth.
Some dummies have a more spherical shape, whereas others are marketed as being more “ergonomic” and have a more flattened paddle-like appearance. Changing to a different design from their usual favourite or puncturing or modifying their existing one may make dummies less appealing to the child – it’s possible they might decide to give it up altogether!
There are other sleep props such as comforters or fidget toys that have less effect on teeth, but children may become similarly reliant on these items to sleep. Having a consistent night routine e.g. reading a story together, having a bath, avoiding screens right before bed time and/or using white noise is more sustainable long term.
Take home messages about thumb and finger sucking
- Stay calm and consistent when making changes
- Reduce the amount of contact time that the thumb or finger has with the teeth during the day and at night
- Try to avoid using dummies as a sleep prop. If the child has already started using a dummy, consider using similar strategies to reduce contact time with the teeth.
Dr Anna Buckeridge is a specialist paediatric dentist who obtained her dental degree and completed her postgraduate training in paediatric dentistry at The University of Western Australia. She is also a member of the Royal Australasian College of Dental Surgeons.
