Thumb and finger sucking

Dental professionals caring for children's oral health

A common habit

Up to a third of children suck their thumb or fingers in the first year of life; it can comfort them when tired and can help them get to sleep. It can start before birth, and can be a deeply ingrained habit. However, by the age of 8 years, only 4% of children are still sucking, so most children stop by themselves, Many children stop when they first go to school as peer pressure and the discomfort of loosening baby teeth discourage the habit.

What problems does it cause?

Thumb and finger sucking has little effect on some children, but it causes problems for others. The severity of any problem caused depends on the child’s growth pattern, the duration of the habit each day and the force or angle of the thumb or finger in the mouth. Possible effects of the habit are:

• Upper front teeth pushed up and forward,
• Lower front teeth pushed down and back,
• Inability to bite on front teeth due to gap between uppers and lowers,
• Lips held apart due to prominent upper teeth,
• Narrowing and distortion of the palate,
• Abnormal swallow, tongue position, or speech,
• Calluses or cracked skin on the sucked digit,
• Psychological effect of poor appearance.

Many of these effects can self correct or improve once the habit stops if early enough or the effect has not been severe.

Parental help to stop

In many cases, a child only needs to be positively reminded not to put the thumb in the mouth – not to be punished for it. If a child is positive, then parents can try some simple procedures to help the child to stop the habit.

An adhesive bandage around the thumb can serve as a reminder when placed before the time when sucking occurs which is usually when tired. Some motivated children will put it on themselves. However, the reminder must be put on consistently to work. For children who suck in bed, wearing an oversized pajama top with sewn up sleeve ends can deter the habit.

Some children respond well to a calendar to track and reinforce their success in stopping the habit (see example).

A child cannot be forced to stop the habit if they do not want to. To break the habit, the child needs to have the mental and emotional maturity to understand the problem and accept responsibility for solving it. This stage of mental development does not usually happen until about 7 years of age.

Dental counselling to stop

If the child needs counselling and/or intervention to stop the habit, it is advisable to wait until the child is in school and is sufficiently mature to cooperate. Unrushed counselling tailored to suit the child can then help most children to break their habit.

Without knowing what harm the habit is causing, a child has little reason to stop. Therefore, the dental professional first explains to the child the problems, what causes them, and why they will get worse if the habit does not stop. The next step is to obtain the child’s agreement that he or she does not want these problems. If the child cannot agree to that, it is best to stop there and try again when the child is more mature.

Once a child has agreed not to want the problems, it is usually not difficult to agree also to stop the habit. The  dental professional then shows techniques that help and motivate the child to stop. For many children this is sufficient to break the habit immediately or within a few days.

Follow up appointments with the  dental professional then serve to reinforce the counselling, to monitor the child’s bite and any associated problems, and usually to congratulate the child on his or her success. Often the bite shows spontaneous improvement, providing positive reinforcement for both child and parents.

Orthodontic appliance intervention

Some children who find it difficult to break the habit need the help of an orthodontic appliance that blocks the comfortable positioning of the digit in the mouth and – very importantly – reminds the child to stop. A fixed appliance is preferable to a removable one because there is no risk of forgetting to put it in.  

As success still depends on the child’s agreement to stop the habit, the  dental professional explains that it is “to remind your thumb that you don’t want it in your mouth anymore”. It is also the reason for not using an appliance with sharp spikes to force an unwilling child.

After the habit is broken, the appliance remains in place for about three months as a reminder if the thumb slips back in. It is also an incentive for the child to stop the habit completely as soon as possible, so the appliance can come out.

In most children, teeth and supporting bone structures begin to move toward their natural position and shape as soon as the habit stops. The dental professional monitors these changes and adjusts the appliance regularly so that it does not impinge on the palate as it changes.