Thumb Sucking and Pacifiers: What They Do to Your Child's Teeth

The quick version

• MyHealth Alberta says thumb sucking is normal in babies and young children, and most children who suck their thumbs stop on their own between ages 3 and 6 (as of October 2026).

• Three Canadian sources differ on when to stop (as of October 2026): the Canadian Paediatric Society says 3 to 4 years for a pacifier, MyHealth Alberta says 4 and older for fingers, thumbs or pacifiers, and the Canadian Dental Association says by age five for thumb or soother sucking.

• The American Academy of Pediatric Dentistry (US) says long-term sucking has been associated with bite changes, a link rather than proof of cause.

• Never punish or shame a child over the habit, say the Canadian Paediatric Society and MyHealth Alberta, which also suggests staying neutral and calm when you talk about it. If you think there is a problem, the Canadian Dental Association says to see a dentist right away.

As of October 2026, MyHealth Alberta says thumb sucking is normal in babies and young children and usually isn't a problem at preschool age or younger, but that long-term thumb sucking after age 4 or 5 may cause dental problems, such as uneven teeth or teeth pushed outward.

If you've watched your toddler drift off with a thumb in their mouth, you've probably wondered what it means for their teeth. Below, we set out what Canadian and US health organisations say about ages, bite changes and kind ways to help, and where they disagree. TLC Family Dental Centre, led by Dr. Kyle Lesko, welcomes children of every age from Leduc and the greater Edmonton area. This is general information, not a diagnosis.

Does thumb sucking damage a child's teeth?

It can, depending on how long and how strongly a child sucks. As of October 2026, MyHealth Alberta says long-term thumb sucking after age 4 or 5 may cause dental problems. The American Dental Association (US) says intensity is a factor, and children who rest a thumb passively are less likely to have difficulty than those who suck vigorously.

The American Academy of Pediatrics (US) says most children stop their sucking habits before they get very far in school, and that too much pressure to stop may cause more harm than good.

At what age do thumb sucking and pacifier habits become a problem?

There's no single age that every source agrees on. As of October 2026, the Canadian Paediatric Society says to plan to give up a pacifier by 3 to 4 years, MyHealth Alberta says to help children 4 and older stop sucking, and the Canadian Dental Association says to aim to stop thumb or soother sucking by age five.

Dates in parentheses are each page's own date, and undated means the page shows none. As of October 2026, the Canadian Paediatric Society (for a pacifier), MyHealth Alberta (for fingers, thumbs or pacifiers) and the Canadian Dental Association (for thumb or soother sucking) give different stop ages, and none of them says why the ages differ.

What can a long-lasting habit do to the bite and the shape of the mouth?

A long-lasting habit has been linked with changes in how the upper and lower teeth meet. The American Academy of Pediatric Dentistry (US) says long-term pacifier use and thumb or finger sucking have been associated with anterior open bite and posterior crossbite, but that the link is associational rather than cause and effect.

In plain words, that describes a pattern rather than proof that the habit causes the change. MyHealth Alberta says long-term pacifier use may cause adult teeth to come in crooked or out of alignment, and that long-term thumb sucking can affect the roof of the mouth.

What do open bite and crossbite mean?

The bite is how the upper and lower teeth line up, says MyHealth Alberta. Two terms you may hear:

• Anterior open bite: the front teeth do not touch when the back teeth are closed together (American Association of Orthodontists, US).

• Posterior crossbite: the upper back teeth come in and meet inside or outside the lower back teeth (American Association of Orthodontists, US).

MyHealth Alberta says a dentist usually checks children for a poor bite, called malocclusion, during regular dental visits. If you're wondering about braces, see our guide to signs your child may need braces.

Is a pacifier or a thumb easier to stop?

A pacifier is often easier to stop, but the American Dental Association (US) says pacifiers can affect the teeth in essentially the same ways as sucking fingers and thumbs. The Canadian Paediatric Society says that when it's time, you can throw a pacifier away, but you can't throw away a thumb.

The sources differ on which is preferable. The Canadian Dental Association says a soother is preferable to thumb sucking when soothing is still needed, because parents can more easily guide and limit it. MyHealth Alberta says research doesn't show that one is preferable, but that thumb sucking may be more difficult to stop.

How can you help your child stop?

Start with calm, praise and patience, not pressure. The Canadian Paediatric Society says never to use punishment or humiliation to make a child give up a pacifier, and MyHealth Alberta says to stay neutral and calm about thumb sucking, not to punish or shame your child, and not to let others make fun of them.

• Praise and reward progress. The Canadian Paediatric Society suggests a reward chart, and praise when your child gives up the pacifier.

• Offer comfort. The Canadian Paediatric Society suggests special cuddles if your child is upset or angry, and asking them to leave the pacifier under the pillow for the "soother fairy".

• Keep little hands busy. MyHealth Alberta suggests puzzles, games and crafts, and limiting screen time, because many children suck their thumbs while watching without thinking about it.

• Plan for nights. The Canadian Paediatric Society says to use a pacifier only for sleep time and comfort, and MyHealth Alberta says it may take up to 3 months before a child can fall asleep without thumb sucking.

What about thumb guards and bitter nail coatings?

Ask your dentist or doctor first. MyHealth Alberta says that if a child continues thumb sucking, you may want to speak to a pediatrician or dentist about devices (such as a thumb guard) that can be tried. It also says to ask your doctor about a non-toxic, bitter-tasting nail coating. A 2015 Cochrane review concluded that orthodontic appliances or psychological interventions seem to help children stop finger or thumb sucking, but that the evidence is low quality.

When should you book a dental visit?

Book early, and don't wait if something worries you. The Canadian Dental Association recommends a dentist assess infants within 6 months of the first tooth coming in or by one year of age, and says to take your child to the dentist right away if you think there is a problem, no matter their age (as of October 2026).

As of October 2026, MyHealth Alberta says a child who sucks a thumb may need treatment if they:

• continue to suck a thumb often or with great intensity around age 4 or older

• ask for help to stop

• develop dental or speech problems as a result of sucking their thumb

• feel embarrassed or are teased or shamed by others

To see what a first visit involves, read about your child's first dental visit.

Frequently Asked Questions

Will my child's teeth go back to normal if they stop?

Sources word it differently. The American Academy of Pediatrics (US) says there's a good chance the bite will correct itself if the habit stops before the adult front teeth come in. The American Academy of Pediatric Dentistry (US) says some evidence indicates changes persist after the habit ends. A dentist can check your child's bite.

Is it okay if my child only sucks a thumb to fall asleep?

As of October 2026, MyHealth Alberta says thumb sucking usually isn't a problem at preschool age or younger, though thumb sucking at night is the hardest habit to break. It also says a child may need treatment if they continue often or with great intensity around age 4 or older.

How do I keep a pacifier safe for my child's teeth?

The Canadian Dental Association says never to dip soothers in sugar, honey or corn syrup, because this can lead to early childhood cavities. As of October 2026, the Canadian Paediatric Society says to wash a pacifier with hot, soapy water after each use, check it for cracks or tears, and replace it every 2 months.

Does it matter when the adult teeth start coming in?

The Canadian Dental Association says to aim to stop thumb or soother sucking by age five, before adult teeth begin to emerge, and that ongoing sucking after that stage may affect how the teeth and jaws grow (as of October 2026). See when kids lose baby teeth for the usual timeline.

Talk it through with Dr. Kyle Lesko in Leduc

If you have questions about your child's sucking habit, or you would like to book a visit for your child, book online or call us at 780.980.5115. You'll find TLC Family Dental Centre at 5209 Discovery Way #4 in Leduc, and we welcome patients from Leduc and the greater Edmonton area. Dr. Kyle Lesko recommends a first visit around a child's first birthday, or within six months of the first tooth coming through, and you can read more about children's dentistry in Leduc or what to expect as one of our new patients.

Sources

Checked in October 2026. Coverage rules and recommendations change, so confirm current details with the organisations below.

• Thumb-Sucking, MyHealth Alberta

• Pacifier, MyHealth Alberta

• Basic Dental Care From Birth to 16 Years, MyHealth Alberta

• Thumb-Sucking in Children: Care Instructions, MyHealth Alberta

• Thumb-Sucking: Helping Your Child Stop, MyHealth Alberta

• Thumb-Sucking Versus Pacifier Use, MyHealth Alberta

• Malocclusion and Orthodontics, MyHealth Alberta

• Pacifiers (soothers), Canadian Paediatric Society

• Pacifiers & Thumb Sucking, Canadian Dental Association

• Your Child's First Visit, Canadian Dental Association

• Thumbsucking, American Dental Association (US)

• Baby Pacifiers & Thumb Sucking: What Parents Need to Know, American Academy of Pediatrics (US)

• Management of the Developing Dentition and Occlusion in Pediatric Dentistry, American Academy of Pediatric Dentistry (US)

• Glossary of Orthodontic Terms, American Association of Orthodontists (US)

• Interventions for stopping dummy or finger or thumb sucking habits in children, Cochrane