Is thumb sucking bad? Side effects + how to curb it

Thumb sucking is common in babies. Sucking is a natural reflex and can be a source of comfort. Most babies and toddlers stop sucking their thumb on their own. But if left unchecked for too long, thumb sucking can cause issues with children’s developing teeth and jaws.

Parents’ Questions About Thumb Sucking Answered

Parents often ask what to do about it, so we reached out to functional pediatric dentist, Dr. Staci Whitman, to weigh in on the subject. Doctor Staci is the founder of NoPo Kids Dentistry where she takes a whole-body, holistic, and functional approach with her patients.

Here are the questions our readers asked along with Doctor Staci’s answers.

Is thumb sucking bad for my child’s permanent teeth?

The effects of thumb-sucking depend on how old the child is. The problem is more time-sensitive for older kids – ages 4 and up.

Three factors play a role in how much of a problem thumb-sucking is: intensity, duration, and frequency. Some children suck on their thumbs very vigorously, like Maggie Simpson, and you can hear the sucking noise clear across the room.

Or if you remove the thumb, it comes out of their mouth with a “pop.” If they do this all day long, every day, these kids are more likely to have problems than kids who just suck on a thumb or finger for a few minutes at bedtime.

When kids are heavy thumb suckers, it doesn’t just change the position of their baby teeth. It actually changes their facial and jaw development. Thumb sucking can lead to two types of malocclusions – open bite and overbite. This can lead to an overbite and a narrow, high palate. It sometimes can also lead to a speech development issue or lisp.

Complications from Thumb Sucking

Some of the issues caused by thumb sucking are:

• an overbite or upper front teeth being pushed out and sometimes up
• tipped back lower front teeth
• a protruding jaw out
• a gap between the child’s upper and lower teeth
• misaligned bite
• a narrow palate (roof of the mouth)
• speech issues, such as a lisp
• tongue not being in a normal position in the mouth

The changes that alter the position of the tongue can affect how your child breathes and eats. It also frequently causes mouth breathing. So, it’s a pretty big deal.

What is mouth breathing?

Mouth breathing is as simple as it sounds. It occurs when a person breathes through their mouth instead of the nose. Mouth breathing is a big oral health concern because it’s one of the leading causes of cavities.

It’s also far less healthy than breathing through the nose, because the nose cleanses and humidifies the air, and it has immune defenses that help to protect against airborne germs. In addition, nasal breathing releases nitric oxide, which allows the blood to transport more oxygen and relaxes blood vessel walls. 

Moreover, when we’re in deep sleep, our brain goes through rest and cleansing, and hormones are released as well. Kids who mouth breathe are chronically exhausted because they never get deep, refreshing sleep. When this goes on day after day, week after week, year after year, the effects can mimic ADHD.

Also, lots of kids who mouth breathe have growth and development issues because growth hormone isn’t being released as it should be.

So, we want to correct thumb sucking if a child is still doing it at four or five, in order to prevent structural changes to the teeth, face, and jaw, and to avoid problems like mouth breathing.

And to stop thumb sucking, we need to figure out why it’s happening. 

What causes a child to suck their thumb?

Sucking is a natural reflex in newborns that helps them to feed. This reflex develops into thumb sucking or sucking other fingers for some babies and toddlers. It’s why many infants rely on pacifiers. It’s a perfectly normal way of self-soothing. It also helps some children fall asleep.

When I see prolonged thumb sucking, the first thing I check for is a tongue tie. This happens when the frenulum – the band of tissue that anchors the tongue to the bottom of the mouth – is too short.

When the tongue is at rest, it’s supposed to be up at the roof of the mouth. When it’s in the proper position, the pressure of the tongue on the palate can cause the release of important hormones including dopamine and oxytocin, which are two “feel good” hormones.

If kids can’t get their tongues up there themselves because of a tongue tie, they’re really smart and they figure out, “I’m going to put my thumb or fingers in there, and that will help release these hormones.” They don’t really realize that’s what happening, of course, but it’s instinctual. That’s why many kids will suck their thumbs or fingers when they’re nervous and they want to calm down.

How can we stop a child from sucking their thumb?

Once we determine the cause of thumb sucking – whether it’s habit, an “addiction,” or a myofunctional or structural issue such as a tongue tie – we can address it. For instance:

• If thumb sucking stems from a tongue tie, a dentist can correct this problem with a simple procedure.
   
• Myo Munchees, which are functional appliances, can help to break your child’s thumb sucking habit while also promoting good tooth, jaw, and facial development.
  
• You can keep the thumb out of your child’s mouth by using long-sleeved t-shirts and tying knots at the ends of the sleeves. Hand puppets, mittens, and thumb-sucking gloves can also be effective.

• For a child who sucks their thumb for comfort, be sure to offer plenty of support, encouragement, positive reinforcement, and gentle reminders. Reward systems and sticker charts can be helpful and reinforcing for four- or five-year-old children.

In most cases, you’ll be able to break the thumb sucking habit within a few months. And the good news is that even older thumb suckers tend to stop when they reach kindergarten age, due to social pressure.

You can find our full holistic dentist Q&A here. Dr. Staci is also engaging and educational on her Instagram.