
Thumb & Finger Appliances
The thumb or finger sucking habit
Children's jaws, rich in blood supply and growing rapidly, are relatively soft and flexible — especially in kids under the age of eight. So it really isn't hard for the constant pressure of a thumb or finger to deform the soft bone around the upper and lower front teeth. Children who are particularly vigorous thumb suckers are even more likely to change the growth patterns of the teeth and jaws.
If the thumb sucking habit persists, it can result in the upper front teeth flaring out and the lower ones moving back and inward. It can also hold back the growth of the lower jaw, while causing the upper jaw to be thrust forward. This can result in misalignment of the teeth, an anterior open bite (where the front teeth fail to close together), collapse of the upper jaw causing crossbite, or other problems. That's why it is important to stop the behavior at an appropriate time, before damage occurs.
How does it work? The semicircular wires of a palatal crib keep the thumb or finger from touching the gums behind the front teeth. Simply preventing this contact seems to take all the enjoyment away from the thumb sucking habit — and without that pleasurable feedback, a child has no reason to continue the behavior. In fact, the device is often successful the first day it's worn.
Using a Habit Appliance
If your child could benefit from a habit appliance, the first step is to get a thorough examination, which may include taking X-rays, photographs and dental impressions. If it's recommended, a crib will then be custom-fabricated to fit your child's mouth, and placed at a subsequent appointment. Afterwards, your child will be periodically monitored until the appliance is removed — typically, a period of months.
Although wearing the crib isn't painful, your child may experience some soreness in the upper back teeth for a few hours after it's first installed. He or she may also have a little trouble falling asleep for a day or two afterward. Plenty of extra attention and TLC are usually all that's needed to make everything all right. While the appliance is being worn, it's best to avoid chewing gum and eating hard, sticky food that might cause it to come loose.
A Word About Tongue Thrusting
Like thumb sucking, tongue thrusting is a normal behavioral pattern in young children. It's actually part of the natural infantile swallowing pattern, which will normally change on its own — by the age of 4, in most children. If the pattern doesn't change, however, it can lead to problems similar to those caused by thumb sucking: namely, problems with tooth alignment and skeletal development. Fortunately, this problem can be successfully treated with a habit appliance that's very similar to a fixed palatal crib.