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What You Should Know About Thumb-Sucking, Pacifiers, and Other Non-Nutritive Oral Habits

kid thumb sucking

Babies have the innate need to suck. It’s a reflex they are born with. Non-nutritive sucking (NNS) refers to a sucking behavior that does not provide any nutritional benefit. So nursing and bottle-feeding are nutritive, while thumb-sucking, finger-sucking, and pacifiers are non-nutritive. Surprisingly, NNS can actually be beneficial for babies.

Benefits for Babies

NNS is the first step in helping babies learn to self-regulate emotions and feelings and to self-soothe. Babies actually begin finger-sucking in utero as early as 20 to 29 weeks gestation. Many soon-to-be moms are surprised to see ultrasound images of their baby with a finger or even a toe near the mouth. The newest ultrasound technology can even identify the sucking motion in the baby’s mouth while thumb-sucking.

Another benefit of NNS is to help children be more focused and attentive, providing comfort and security as well. Sucking tends to occur most often when the child is feeling bored or upset and when tired. Nearly 100 percent of children will suck their thumbs.

An Addiction-Like Experience

Thumb-sucking or pacifier use in and of itself isn’t a problem for children, and most discontinue the habit on their own between the ages of 2 and 4. It becomes a problem if it continues beyond age 4 or so — at which point it has become a habit, and a hard one to break.

There are physiological changes that occur when kids suck their thumbs (or pacifiers). There is a calming chemical called beta endorphin that is produced. The endorphins attach to the opiate receptors in the child’s brain, and a pleasurable association is created. The pleasurable feeling creates an addiction-like experience, and that’s what makes it so difficult for children to stop.

Problems with Teeth, Tongue, and Palate

Parents can easily see the changes in their child’s dentition resulting from prolonged sucking. The changes can be dental and skeletal. There is often an anterior open bite, and the teeth are pushed out. The roof of the mouth, or palate, becomes high and arched. Very often there is a thumb-shaped depression in the hard palate.

What parents can’t see is the change in the tongue’s resting posture that thumb-sucking encourages. The normal rest position of the tongue from around age 4 and on is within the upper dental arch but away from the teeth. In the vast majority (over 99 percent) of kids who suck beyond age 5, the tongue assumes a low forward rest position, and the tongue thrusts forward during swallowing and speech in some cases.

With the open bite comes difficulty biting certain foods, like bagels and pizza. Children may develop aversions to certain textures and consistencies as well.

Children’s self-esteem can also suffer because of prolonged oral habits. They may be apprehensive about attending sleepover parties or other events, fearing the ridicule should the fingers slip into their mouth in front of peers. They may be teased because their teeth are so protruded or because eating food with an open bite can be messy.

What Parents Can Do

So what can parents do? Nagging and reminding your child to get the fingers out of the mouth obviously doesn’t work, since there are so many kids who still suck. Noticing when your child isn’t sucking and providing some praise can be helpful, if just for a moment. Punitive dental appliances aren’t effective long-term and can cause the child pain and distress.

Keeping the child’s hands busy with manipulatives and other hands-on activities can help short-term, as can limiting TV time, since that tends to be a common environment for thumb-sucking. Long car rides can be tricky; a bag of small toys and objects to explore could offer an alternative to sucking.

Where to Get Help

When you feel you have exhausted your bag of parental tricks, the next best step is to look for a certified orofacial mycologist (COM) to help. COMs are speech pathologists or dental hygienists who have taken advanced course work and training. They should be using a non-punishing approach, and above all work only with kids who are ready to stop and want to stop. Parents may want their child to stop, but the motivation really has to come from within your child.

Kids as young as 4 can be guided through a program to stop thumb-sucking when they are ready. Stopping early also increases the likelihood of normal dental and facial development. To find a COM near you, go to the website of the International Association of Orofacial Myology and you can find a directory of specialists ready to support you.


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