Help! My Child Has "Shark Teeth" (Two Rows of Teeth Explained)

Why this happens, when to worry, and why age 8–10 is the perfect time to check.

It is a common scenario in Christchurch households: You are helping your child brush their teeth before bed, you look inside their mouth, and suddenly you spot it.

Behind their baby teeth, a second row of jagged adult teeth is poking through.

It looks like a shark’s mouth. It looks crowded. And for many parents, it looks like an emergency.

First, take a deep breath. This condition—known officially as Ectopic Eruption (or casually as "Shark Teeth")—is incredibly common in children aged 6 to 10. While it looks alarming, it is rarely a dental emergency. However, it is a clear signal from your child’s body that their developing jaw might need a little help.

At Duxton Dental in Riccarton, we see "Shark Teeth" almost every week. Here is everything you need to know about why it happens, how we manage it, and how to win $1,000 off treatment by booking a check this March.

What are "Shark Teeth"?

"Shark Teeth" is the term used when permanent adult teeth sprout from the gums behind the baby teeth, creating a double row.

Normally, an adult tooth pushes up directly underneath the baby tooth. This pressure dissolves the root of the baby tooth, making it loose until it falls out, leaving a nice clear path for the adult tooth to take its place.

However, sometimes the adult tooth gets a little off track. If it develops at a slight angle, or if there simply isn't enough space in the jaw, it will take the path of least resistance—popping up behind the baby tooth. Because the baby tooth’s root hasn’t been dissolved, it stays firm, and the adult tooth is forced to grow in the second row.

Is this a sign of a bigger problem?

While Shark Teeth aren't painful, they are often a symptom of crowding.

Think of your child’s jaw like a parking lot. If there are 12 cars (teeth) trying to park but only 10 spaces, the cars have to double-park.

If your child has Shark Teeth, it is a strong indicator that their jaw may be too narrow to accommodate all their adult teeth naturally. This doesn't just look messy; it can affect:

• Hygiene: Food gets trapped easily between the two rows, increasing decay risk.
• Bite: It can force the jaw into an uncomfortable position.
• Confidence: Kids notice when their smile looks different from their friends'.

This is exactly why we talk about the "Magic Window" (Ages 8–10).



The "Magic Window": Why Age 8–10 is Critical

Many parents believe they should wait until all baby teeth have fallen out (usually around age 12 or 13) before seeing a dentist about orthodontics.

This is a myth. In fact, waiting until age 13 can make treatment more difficult.

By age 13, the jaw has mostly finished growing. If the jaw is too narrow (causing Shark Teeth), the cement has essentially "set." Fixing it then might require extracting healthy adult teeth to make room.

However, between ages 8 and 10, your child is in a rapid growth phase. Their jaw is still developing. By intervening now ("Interceptive Care"), we can often:

1. Widen the jaw gently to create more parking space.
2. Guide adult teeth into the correct spots as they erupt.
3. Prevent the need for extractions or complex surgery later in life.

If you see Shark Teeth, your child is waving a flag that says: "Hey, I might need some space here!"

How we treat Shark Teeth at Duxton Dental

So, you’ve found the double row. What happens next?

When you bring your child to our Riccarton clinic, we don't just reach for the pliers. We take a holistic look at why it is happening.

1. The "Wiggle" Strategy

If the baby tooth is already loose and the adult tooth hasn't come up too far, we might simply recommend you encourage your child to wiggle it! Sometimes, nature just needs a nudge.

2. Gentle Extraction

If the baby tooth is stubborn (rock solid) and the adult tooth is getting taller, we may recommend a gentle extraction of the baby tooth. This gives the adult tooth the space it needs to drift forward into the correct position.

3. Orthodontic Expansion

If we extract the baby tooth but the "parking lot" is still too small, the problem will just happen again with the next tooth. This is where we might look at a simple expander or plate to widen the arch.