Sucking is a natural reflex for children. As infants get older it serves many purposes. Sucking on their thumbs, fingers, pacifiers or other objects may make babies feel secure and happy and help them learn about their world. Young children may also suck to soothe themselves. Since thumb sucking is relaxing, it may help them fall asleep.

After the permanent teeth come in, sucking may cause problems with the proper growth of the mouth and alignment of the teeth. It can also cause changes in the roof of the mouth. The intensity of the sucking is a factor that determines whether or not dental problems may result. If children rest their thumbs passively in their mouths, they are less likely to have difficulty than those who vigorously suck their thumbs. Some aggressive thumbsuckers may cause problems with their baby (primary) teeth. If you notice changes in your child’s primary teeth, consult your dentist.

Children should have ceased sucking by the time the permanent front teeth are ready to erupt. Usually children stop between the ages of two and four years.

Pacifiers can affect the teeth essentially the same ways as sucking fingers and thumbs. However, it is often an easier habit to break.
Tips:

• Praise children for not sucking, instead of scolding them when they are.
• Children often suck their thumbs when feeling insecure or needing comfort. Focus on correcting the cause of the anxiety and provide comfort to your child.
• For an older child, involve him or her in choosing the method of stopping.
• Your dentist can offer encouragement to a child and explain what could happen to their teeth if they do not stop sucking.
• If the above tips don’t work, remind the child of their habit by bandaging the thumb or putting a sock on the hand at night. Your dentist or pediatrician may prescribe a bitter medication to coat the thumb or the use of a mouth appliance.

Source: ADA, American Dental Association.  http://www.ada.org/2977.aspx