The Effect of Thumb Sucking on Teeth and How to Get Your Child to Stop

Thumb sucking is a normal reflex action among young children. It can start for babies even while in utero and may continue through toddlerhood.

Thumb sucking can actually be beneficial for them as it’s a way to self soothe when they’re young and don’t know any other ways to calm themselves.

The act of thumb sucking doesn’t just help children feel relaxed, secure, and happy. According to a study, thumb sucking can also make them less susceptible to allergies in later childhood.

At What Age Might Thumb Sucking Cause a Dental Problem?

For all its purported benefits, there are some detrimental effects of thumb sucking, namely, its adverse effects on a child’s oral and dental development. This is a major concern for parents who want nothing but the best dental care for kids.

While parents have nothing to worry about for infants and toddlers who are thumb suckers, it’s only appropriate for them to be alarmed if their kids continue to do it past the age of 4 at the latest.

After age 4 is when thumb sucking can really start to alter the formation of the teeth and cause oral motor, speech, and chewing problems.

My personal experience

My daughter sucked her thumb until about 3.5 years old to which point we did everything we could to get her to stop. She is now 5 and actually has beautiful teeth, but they weren’t always that perfect.

Personally, my dentist also told me that children’s mouths and teeth are still moving, shifting, and growing until around 5 years old. If they stop sucking their thumb before this age, any thumb sucking effects should be able to change back.

Here is a photo of my daughter’s teeth when she was about 2.5 years old and sucking her thumb vs. her teeth at 5 years old without sucking her thumb for 1.5 years.

The top 2 are at 2.5 and the bottom two photos are at 5 years old. Perfect teeth after being a thumb sucker for 3 years!

Of course some teeth positioning may just be genetics, but I was always so worried that her teeth would be ruined from thumb sucking and they weren’t!

Effects of Thumb Sucking on Children’s Teeth

Let’s take a look at some of the effects of thumb sucking on a child’s teeth and—if you have a thumb sucking child—tips on how to get them to stop.

1. Malocclusion

There are two different ways that children suck their thumb. Some thumb sucking kids will just rest their thumbs inside their mouth and don’t actively suck on them.

However, most thumb sucking children do it with plenty of vigor and motion. This is the way that makes them most prone to dental and oral issues like malocclusion.

A malocclusion refers to misaligned teeth, which the repetitive pressure of frequent and vigorous thumb sucking may cause. It can be classified as:

• Class I— The most common type of malocclusion, where the upper teeth overlap the lower teeth slightly, but with a typically normal bite.
• Class II—The upper teeth severely overlap the lower teeth and become directed outward; an overbite.
• Class III—The lower teeth unnaturally overlap the upper teeth; an underbite.

By the very description of the types of malocclusion, we can already see the impact that the condition can have, not only on the appearance of a child’s teeth, but also on his or her overall looks.

A child’s teeth, jaw, and mouth and facial muscles—all part of the orofacial complex—develop as they get older. If he or she has a malocclusion, the condition will likely affect the child’s entire facial structure, the appearance of which will depend on the severity of the misalignment.  

While an orthodontist can fix malocclusion using braces, it would be infinitely better if your child won’t need them in the first place because you were able to stop his or her thumb sucking habit early on.

2. Biting, Chewing, and Speech Problems

Thumb sucking doesn’t just impact your child’s physical appearance through dental problems.

Since thumb sucking also affects the development of the teeth, jaw, and palate, your child might also encounter some issues with the physical aspects of using their mouth. This includes biting and chewing food and speaking.

Children with malocclusions because of their thumb sucking habit may also develop speech impediments, as their tongue will tend to push forward through their misaligned teeth. In some cases, their malocclusions and lack of tongue control lead to a lisp or other speech issues.

With speech issues, your children will likely find it hard to communicate effectively, which can make them feel frustrated, angry, and isolated.

3. Exposure to Bacteria and Germs

Toddlers typically play with their toys and touch just about everything that catches their fancy.

Another effect of chronic thumb sucking is that these kids are directly transmitting whatever germs or bacteria they get from touching stuff into their mouths. With their constant exposure to germs, thumb sucking children are often at higher risk for infections.

How To Get Your Child To Stop Thumb Sucking

Many children usually give up thumb sucking by the age of 4 at the latest, although it’s not unheard of for them to resume the habit when they’re bored, hungry, or stressed out.

They may or may not simply stop on their own as they mature and realize that it’s not a “big kid” thing to do or this may be a good time for you to give them assistance in breaking the habit.

If you have a child older than 4 who continues to be a chronic thumb sucker, you might want to try the following approaches to get them to stop thumb sucking quickly. You’ll want to stop this bad habit before his or her permanent teeth come in, at which point the thumb sucking will become a major concern:

• Talk to your child about it—Talking to school-age children about their thumb sucking habit could work, especially if other kids in school are making fun of them because of it. You can tell them that if they don’t like being teased and they want it to stop, they should stop sucking their thumbs.

Some kids may even stop it automatically once the peer pressure sets in, even in preschool. Of course, it’s not ok to let them accept being teased, but they should understand that thumb sucking is for little kids and it’s no longer something that they need to do.

• Offer other activities as a distraction or substitution —Kids who suck their thumbs typically do so because of stress, boredom, or hunger. Identify the exact trigger that makes them put their thumb in their mouth. When such a moment comes, have their hands do something else or offer something that could substitute for sucking their thumb.

This could be giving them a new toy, crayons and paper for doodling, or anything that will keep their hands occupied. It can also help to give them something that may be just as soothing to them like a stuffed animal or blanket if they tend to suck their thumb at night.

• Praise your child once the thumb sucking stops—Once you notice that your child doesn’t suck his or her thumb anymore, even when known triggers set in, always have a kiss, a hug, and encouraging words at the ready. After all, few things work as well on kids as positive reinforcement.

You can even try to use a sticker and reward chart where they earn a sticker for each occasion that they don’t suck their thumb and get a prize when they’ve accumulated all of their stickers.

• Refrain from scolding your child if the habit resurfaces—As mentioned above, your child may be sucking his or her thumb because they may be nervous or anxious. If you catch your child resorting to thumb sucking again, don’t resort to scolding as you can only make his or her anxiety worse. Be as gentle and calm as possible when you remind your child about the importance of giving up the chronic thumb sucking.

• Use products designed to stop thumb sucking—Commercially-available plastic thumbs or finger covers may be a rather expensive way of getting your kid to quit thumb sucking, but they’re a sensible option if all else fails. Have your child wear it for about two weeks and see if he or she manages to kick the habit. This stop-thumb-sucking nail polish also works great as it gives them an awful taste in their mouths if they start to suck their thumb.

It’s true that children with a thumb sucking habit will eventually stop doing it when they grow older. However, parents will still need to make an effort to get them to stop as early as possible.

This will be the only way to help them avoid developing dental and oral problems that come with chronic thumb sucking later on in life. Braces and orthodontics are a very expensive way to fix a thumb sucking habit!

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