Why Is a Tooth Growing Behind Another Tooth? Shark Teeth in Kids Explained

Key Takeaways

• Shark teeth occur when a permanent tooth erupts behind or in front of a baby tooth that hasn’t fallen out yet, creating a double row of teeth
• This is usually temporary and harmless; the baby tooth typically falls out within weeks or months once the permanent tooth’s root is established
• See a dentist if the permanent tooth is very far out of alignment, if both baby and permanent teeth aren’t moving, or if the problem persists beyond a few months

Understanding Shark Teeth in Children

You open your child’s mouth and do a double take. There’s a tooth growing behind the baby tooth, or in front of it, creating what looks like a second row. Your first instinct is to panic. Is something wrong? Will your child need braces? This phenomenon has an apt nickname: shark teeth. And while it looks alarming, it’s usually nothing to worry about.

Shark teeth occur when a permanent tooth erupts from the gum while the baby tooth above or below it is still firmly in place. Instead of the baby tooth falling out first and creating space, the permanent tooth comes in alongside it. The result is a double row of teeth that makes your child look like a tiny shark. It’s startling but usually temporary.

The good news is that in most cases, shark teeth resolve themselves. The baby tooth eventually falls out, and the permanent tooth gradually shifts into its proper place. No intervention is needed. However, knowing when to see a dentist and when to simply wait helps you feel confident about what’s happening.

Why Teeth Grow in Double Rows

Baby Teeth Not Falling Out on Schedule

Normally, when a permanent tooth is ready to erupt, the root of the baby tooth above or below it dissolves (resorbs). This weakens the baby tooth and allows it to become loose and eventually fall out. The permanent tooth then moves into the space left behind.

Sometimes this process gets out of sync. The permanent tooth is ready to erupt before the baby tooth’s root has fully resorbed. The baby tooth is still firmly anchored. So the permanent tooth comes in alongside it instead of replacing it. This is especially common with front teeth where space is tight.

Anatomy and Space Constraints

Permanent teeth are larger than baby teeth. When a permanent front tooth erupts, it needs a certain amount of space. If the baby tooth is still in the way and the permanent tooth can’t push through the gum where it should, the permanent tooth sometimes erupts to the inside or outside of the normal tooth position, creating the double-row appearance.

The jaw might also be slightly too narrow for permanent teeth to fit side by side with their baby predecessors. As the jaw continues growing, there’s eventually enough space for the tooth to shift into position once the baby tooth falls out.

Genetics and Jaw Development

Some families seem more prone to shark teeth. This is likely genetic. If you had shark teeth as a kid, your child probably will too. Jaw size and the timing of tooth eruption are inherited traits. Children with crowded permanent teeth or with jaws that grow more slowly might be more likely to develop shark teeth.

Is Shark Teeth a Problem?

Usually Temporary and Self-Resolving

In most cases, shark teeth aren’t a problem. The baby tooth falls out within weeks or a few months, and the permanent tooth gradually shifts forward into proper position. The jaw continues growing, and permanent teeth settle into alignment naturally as more baby teeth are shed.

Parents often worry that shark teeth means their child will need extensive orthodontic work. Usually, this isn’t the case. The temporary double row resolves on its own. Later, when all permanent teeth have erupted and the jaw has finished growing, the dentist or orthodontist can assess whether braces are needed. Many children with shark teeth have perfectly aligned permanent teeth without any intervention.

When Shark Teeth Indicate Crowding

Sometimes shark teeth are a sign of moderate to severe crowding. If multiple permanent teeth erupt out of position, or if the permanent tooth is very far from where it should be, it might indicate the jaw is too small for all the permanent teeth. This could mean future orthodontic treatment will be needed.

However, seeing one or two teeth come in out of position isn’t necessarily a sign of severe crowding. Many children with mild shark teeth end up with perfectly fine tooth alignment once all permanent teeth erupt. A dentist can assess your child’s specific situation and advise whether early intervention is likely to be needed.

When to See a Dentist About Shark Teeth

Mild Cases Can Be Monitored at Home

If your child has one or two teeth erupting out of position and the baby tooth is becoming loose, you can often simply wait. The baby tooth should fall out within weeks. Once it does, the permanent tooth will likely shift forward into a more normal position over the coming months.

During this waiting period, encourage your child to wiggle the loose tooth gently. This helps the process along. Avoid forcing the tooth out. It will come out when it’s ready. Keep the area clean and monitor that no infection develops around the loose tooth.

When Professional Help Is Needed

See a dentist if the baby tooth shows no signs of loosening after several months, if the permanent tooth is very far out of alignment, or if multiple permanent teeth are erupting out of position. Your dentist can assess whether extraction of the baby tooth would help or whether other intervention is needed.

Also see a dentist if you notice signs of infection around the baby tooth, such as swelling, redness, or discharge. While uncommon, infection can develop around a loose tooth.

What to Expect at the Appointment

Your dentist will examine the baby and permanent teeth, assess how loose the baby tooth is, and determine the permanent tooth’s alignment. In most cases, the dentist will recommend waiting and monitoring. Occasionally, if the baby tooth is very stubborn and preventing the permanent tooth from moving into position, the dentist might extract it to allow the permanent tooth to shift.

Your dentist can also reassure you about alignment. Many parents worry their child will need braces based on temporary shark teeth, but the dentist can usually tell whether the crowding is mild or more significant.

Managing Shark Teeth at Home

Cleaning and Hygiene

Shark teeth can make cleaning more difficult because there are more surfaces and the teeth are crowded together. Help your child brush thoroughly, ensuring the toothbrush reaches between the overlapping teeth. Flossing might be tricky, but try to get floss between at least the front teeth if possible.

The good news is that this challenging cleaning phase is temporary. Once the baby tooth falls out and the permanent tooth shifts, cleaning becomes easier again.

Nutrition and Diet Adjustments

The crowded teeth might make chewing slightly uncomfortable for your child. Offer soft foods if chewing causes discomfort. Avoid hard, sticky candies that could damage the loose baby tooth or get stuck between teeth. This phase doesn’t require major dietary changes, just mindfulness about foods that might cause problems.

Avoiding Forced Extraction

Never try to forcefully extract a baby tooth that hasn’t become loose on its own. You can cause damage to the tooth socket, increase bleeding, or traumatise your child. Let the natural process happen. If the tooth is still firmly in place after several months, that’s when professional extraction might be appropriate.

The Role of Jaw Growth and Development

Jaw Growth Continues Through Childhood

Children’s jaws don’t stop growing at a certain age. Growth happens gradually throughout childhood and into the teenage years. As the jaw grows, it widens and lengthens, creating more space for permanent teeth. This jaw growth often naturally resolves crowding issues that seemed significant when the child was younger.

This is why waiting and monitoring is often the right approach with shark teeth. The jaw is still growing, and space might open up naturally as growth continues.

Permanent Tooth Eruption and Self-Correction

As more permanent teeth erupt and baby teeth are shed, permanent teeth gradually shift and settle into more ideal positions. This process of shifting and settling happens naturally over months and years. A tooth that erupted far out of position might naturally move closer to proper alignment as surrounding teeth settle.

Shark Teeth and Future Orthodontic Needs

Most Children Don’t Need Early Intervention

Seeing shark teeth doesn’t mean your child will definitely need braces. Many children with temporary shark teeth end up with perfectly aligned permanent teeth without any orthodontic treatment. The temporary crowding resolves naturally as the jaw grows and baby teeth are shed.

Orthodontists usually wait until a child is 7 to 10 years old before doing a comprehensive assessment for potential braces. At that point, most permanent teeth have erupted, and the orthodontist can see the overall picture. This is the appropriate time to discuss whether braces will be needed.

When Early Orthodontics Might Be Recommended

In rare cases, early orthodontic intervention is recommended. This might happen if a child has severe crowding, an extreme bite problem, or if a permanent tooth is severely out of position and blocking other teeth from erupting. Your dentist can advise whether early orthodontic evaluation is warranted for your child’s specific situation.

Why Is a Tooth Growing Behind Another Tooth? FAQs

Why is there a tooth growing behind another tooth?

A tooth grows behind another tooth when the permanent tooth erupts before the baby tooth falls out. Normally, the baby tooth’s root dissolves and the tooth becomes loose, allowing it to fall out and make space for the permanent tooth. Sometimes this process gets out of sync, and the permanent tooth comes in before there’s space for it. The permanent tooth often erupts to the side or back.

Will shark teeth cause problems?

Most shark teeth are temporary and cause no lasting problems. The baby tooth falls out within weeks or months, and the permanent tooth gradually shifts into a more normal position. Cleaning is slightly more difficult during the overlapping phase, but this passes. Most children with shark teeth end up with normal tooth alignment without any treatment.

Why is my teeth not growing back?

If a baby tooth falls out but the permanent tooth behind it doesn’t erupt for a while, this is usually normal. Sometimes there’s a delay of several months between when a baby tooth falls out and when the permanent tooth erupts. As long as the permanent tooth eventually comes in, there’s nothing to worry about. If several months pass with no sign of the permanent tooth, mention it to your dentist.

Why isn’t my tooth coming out?

If a baby tooth seems to be in the way of a permanent tooth but isn’t loosening, the baby tooth’s root might not be resorbing as quickly as the permanent tooth is erupting. This can create the shark teeth situation. In most cases, the baby tooth eventually falls out on its own. If it remains very firmly in place for several months, your dentist can extract it to allow the permanent tooth to move into position.

Do shark teeth require treatment?

Most shark teeth don’t require treatment. Waiting and monitoring is the standard approach. If the baby tooth isn’t loosening after several months, if the permanent tooth is very far out of position, or if the crowding seems severe, your dentist might recommend extraction of the baby tooth or referral to an orthodontist. But the majority of shark teeth cases resolve naturally without intervention.

Sources

American Academy of Pediatric Dentistry (AAPD). “Eruption of Primary and Permanent Teeth.” Information on normal tooth eruption patterns and what happens when eruption is delayed or out of sequence.

American Dental Association (ADA). “Teeth Development and Eruption.” Guidance on baby and permanent tooth eruption, including shark teeth and when to seek dental care.

Mayo Clinic. “Children’s Dental Health.” Information on common dental issues in children, including shark teeth and when intervention is needed.

Journal of the American Dental Association. “Ectopic Eruption and Crowding in Permanent Teeth.” Research on why permanent teeth erupt out of normal position and the outcomes of waiting versus early intervention.