So you’ve spotted something a bit odd in your kid’s mouth. There’s a tooth growing behind a baby tooth, and it looks like your child has two rows of teeth. Before you start panicking, take a breath. This is actually more common than most Melbourne parents realise, and in most cases, it sorts itself out with very little fuss.
That said, it’s always worth knowing what you’re looking at, why it happens, and when it’s time to pick up the phone and book a dental check-up.
What Are Shark Teeth? (And Why Does My Child Have Them?)
You might have heard the term “shark teeth” floating around in parent circles, and yes, the nickname makes total sense once you’ve seen it. Sometimes called “shark teeth,” this is when adult teeth begin growing behind baby teeth before the baby teeth have fallen out, resulting in two rows of teeth that look a bit like a shark’s mouth.
Officially, dentists refer to this as ectopic eruption, but “shark teeth” is the term that tends to stick.
The good news? About 10% of kids experience shark teeth, and it’s usually nothing to worry about. It’s particularly common with the bottom front teeth, though it can also affect the upper front teeth and, less often, the back molars.
Here’s a quick breakdown of where shark teeth most often appear:
|
Location |
How Common? |
| Lower incisors (bottom front teeth) | Most common |
| Upper front teeth | Less common |
| Back molars | Occasional |
Why Permanent Teeth Sometimes Erupt Behind Baby Teeth?
Understanding why this happens can help ease the worry. There are a few reasons your child’s permanent teeth might be coming in behind their baby teeth rather than pushing them out cleanly.
-
The Baby Tooth’s Root Isn’t Dissolving Properly
Normally, when a permanent tooth starts pushing upward, it puts pressure on the root of the baby tooth above it. That pressure causes the baby tooth root to dissolve gradually, the tooth becomes a wiggly tooth, and eventually it falls out, making room for the new one to take its proper place.
When the permanent tooth doesn’t follow this typical pattern, the baby tooth’s root may not dissolve as expected, and instead of the baby tooth becoming loose and falling out, the permanent tooth erupts behind it.
-
Not Enough Room in the Jaw
If a child’s jaw doesn’t have enough space to comfortably fit all their permanent teeth, crowding can lead to unusual eruption patterns, including teeth coming in behind baby teeth.
-
The Tooth Is Growing at an Angle
Sometimes it’s simply a matter of direction. Kids develop shark teeth when their permanent teeth emerge at an angle, growing behind a baby tooth instead of pushing it out.
-
Genetics
If a parent or close relative experienced similar issues during childhood, it’s more likely their child might also develop a double row of teeth, since genetic factors can influence the timing of tooth eruption and overall spacing in the mouth.
Common causes at a glance:
- The root of the baby tooth is not dissolving as it should
- Crowding or limited jaw space
- The permanent tooth is growing at an angle
- Genetics and family history
- Delayed loss of baby teeth
When Do Baby Teeth Usually Fall Out?
Most children start losing their baby teeth around age 6, with the lower incisors typically going first. Children typically start losing their baby teeth at about age 5, and their front incisors or lower front teeth begin developing at age 6, making this the most likely time for shark teeth to appear.
Here’s a general timeline for when children start losing their primary teeth:
|
Tooth Type |
Typical Age of Loss |
| Lower central incisors | Around age 6 |
| Upper central incisors | Age 6 to 7 |
| Lateral incisors | Age 7 to 8 |
| Canines | Age 9 to 12 |
| Molars | Age 9 to 11 |
Keep in mind, every child is different. Some teeth come earlier, some later. A variation of a year or two is usually perfectly normal.
When Parents Should Seek Professional Advice?
Here’s where it gets important. Most of the time, shark teeth resolve on their own. The tongue naturally pushes the permanent tooth forward into position, and the baby tooth eventually loosens and falls out. But there are situations where you really do need to see a dentist.
Book a dental appointment if:
- The baby tooth is not loose at all, even slightly, after the permanent tooth has been visible for several weeks
- Your child is experiencing pain or discomfort around the area
- The permanent teeth coming through look significantly misaligned
- The baby tooth isn’t loosening despite the new tooth being well established
- You notice shark teeth in the molars, which are less likely to resolve without help
- Your child is older than 8 and still has this happening without any sign of the baby tooth moving
If the baby teeth don’t loosen after the permanent teeth begin to erupt, or if your child experiences significant discomfort, it’s time to visit the dentist, who can evaluate whether tooth extraction or orthodontic treatment is needed to ensure the teeth align correctly.
In some cases, the dentist may recommend extraction of the baby tooth to give the permanent tooth the room it needs to move into the right position. Dental x-rays may be used to assess the root of the baby tooth and determine the best course of action.
In rare cases, if the permanent teeth have already shifted noticeably out of alignment, a referral to an orthodontist may also be discussed.
What About the Statistics?
Regular dental check-ups really do matter. According to the Australian Dental Association’s 2024 Children and Young People Oral Health Tracker, 34% of Australian children aged 5 to 6 have experienced decay in their primary or baby teeth, and 27% of those aged 5 to 10 have untreated tooth decay in their baby teeth.
These numbers are a strong reminder that getting your child to the dentist regularly, especially during those key baby teeth years, makes a real difference to how their adult teeth develop.
The ADA also reports that 11 in every 1,000 Australian children aged 5 to 9 were admitted to hospital for preventable dental issues in 2021 to 2022, up from 9.5 per 1,000 in 2018.
The takeaway here is clear: preventive dental care and routine check-ups can help catch these issues early, before they turn into something bigger.
Children’s Dental Assessments at G Dental, Greensborough
At G Dental, our children’s dentistry team understands that a visit to the dentist can feel like a big deal, especially for little ones. We work with Melbourne families across Greensborough and the surrounding suburbs to make dental check-ups a positive experience from the very start.
If you’ve noticed your child has a tooth growing behind a baby tooth, or you’re simply due for a routine check-up, our team is here to help. We offer:
- Comprehensive children’s dental check-ups to monitor tooth eruption patterns
- Dental x-rays when needed, to assess roots and jaw development
- Gentle extractions if a stubborn baby tooth needs a little help on its way out
- Preventive care advice tailored to your child’s age and dental stage
- Friendly, reassuring care for anxious little patients
Whether you’re in Greensborough, Watsonia, Bundoora, or anywhere across Melbourne’s north-east, we’d love to bring your child in for a check-up and put your mind at ease.
Book your child’s dental appointment with our Greensborough team today.
Learn more about our Children’s Dentistry
Frequently Asked Questions
What exactly are shark teeth in kids?
Shark teeth is the nickname for when a child’s permanent teeth come through behind their baby teeth, creating two rows of teeth. It affects around 10% of children and is usually harmless.
Should I wiggle my child’s baby tooth to help it fall out?
Gentle wiggling is fine if the tooth is already even slightly loose. Avoid forcing it if it won’t move, and see a dentist if the tooth isn’t loosening after a few weeks.
Will shark teeth fix themselves without treatment?
Often, yes. The tongue naturally pushes the permanent tooth forward, and the baby tooth falls out on its own. But if the baby tooth isn’t loosening, a dentist may need to extract it.
When should I take my child to a dentist for shark teeth?
Book a dental check-up in Greensborough if the baby tooth shows no sign of loosening, if your child has discomfort, or if the shark teeth appear in the molar area, as these are less likely to self-resolve.
Can shark teeth cause long-term dental problems?
In most cases, no. If addressed early, the permanent teeth usually move into the correct position on their own or with minimal help. Regular dental care ensures any issues are caught and managed early.
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