What Effects Will Thumb-Sucking Have on Teeth?

My 20-month-old daughter sucks her thumb, but my mother-in-law told me this will permanently damage her teeth? Is this true?


During the first two years, thumb-sucking shouldn't cause any concern. Sucking is a baby's inborn reflex -- without it she would not seek food. However, if after the age of three your child still continues, it can affect the position of her teeth and the shape of her jaw. The pressure of thumb-sucking may force the teeth out of position and narrow the dental arches. Orthodontic care will eventually be needed to make the mouth look normal and work efficiently again.

If your child continues to suck her thumb after age two, we recommend positive behavior modification and putting a cotton sock over her hand, taping the end of her thumb, or using flavored nail polish . . . rather than punishment. Remember that thumb-sucking is a natural instinct.