Why does my child have two rows of teeth? What to Do About Hyperdontia

Having two rows of teeth as a child can be very common. But when should you take him or her in to see the dentist?

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two rows of teeth

My son's adult teeth are coming in, but the baby teeth aren't falling out! He now has two rows of teeth on the bottom. What can be done about this? Is this an emergency or can I wait until his next dental check-up, which is several months away?


This is very common. Normally, an adult tooth erupts directly underneath the root of the baby tooth, causing the baby tooth to become wiggly and fall out.

But if the adult tooth erupts somewhere else — usually behind the baby tooth — both the adult tooth and baby tooth can be present at the same time, usually with one behind the other.

This effect is also referred to as “shark teeth,” since sharks have two rows of teeth.

This usually looks concerning, but it’s very common and rarely becomes a problem.

If the baby tooth is moving or loose and the adult teeth are coming in, I would wait and see if the baby teeth come out.

If the baby teeth are not loose and both baby and adult teeth are at the same height, then I’d recommend scheduling an appointment with your family dentist or a pediatric oral surgeon to discuss whether the teeth need to be removed. However, the dentist will likely want to observe the teeth at first and wait to see what happens.

I wouldn’t worry, but do check the height of the teeth to see if they’re wiggly or not to determine whether or not you should schedule an appointment sooner rather than later.

Hope that helps!

Mark Burhenne DDS

Read Next: What is Baby Bottle Tooth Decay?

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  1. Sekou Safiatou says:


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  2. Deanna Jones says:

    I remember growing up with an extra tooth that grew behind one of my front teeth. The dentist that my mom took me to had it pulled out. My son also has the same problem with his teeth, so I was wondering if this tooth growth pattern is caused by genetics. It’s interesting that it’s common for an adult tooth to miss the root of the baby tooth and grow somewhere else. I didn’t realize that I can wait for the baby tooth to fall out if this happens. I’ll remember to take my child to see a dentist if the adult tooth eventually grows to be as long as the baby tooth without getting loose. Thanks for the tips!

  3. Steven Harrison says:

    Thanks for the reassurance. The multiple rows of teeth look terribly problematic. It’s nice to know it’s nothing to worry about. I had never heard about it, but apparently it’s common.

    • My 4-year-old has this going on. It actually startled me at first. It didn’t look normal. I am glad to know this is fairly common though. However, I am still going to schedule an appointment with her dentist.

  4. Olivia Sherwin says:

    This is some great information, and I appreciate your point that a child having their adult teeth come in behind their baby teeth is common. My son has this happening in his mouth, and I was worried that it was an emergency. I’ll definitely keep an eye on it to see if his baby teeth get loose at all, and I’ll be sure to talk to his dentist if they don’t. Thanks for the great post!

  5. Lillian Schaeffer says:

    Thanks for sharing this great post about why children sometimes have two rows of teeth. My son has had this for a while, and I’ve been concerned because his baby teeth haven’t been loosening. I’ll definitely look into visiting my dentist to see if they need to be removed or if they will fall out on their own eventually.

  6. Judy Wilson says:

    It’s interesting how common it is for kids to have one adult tooth erupt underneath a baby tooth. I thought that it was unusual when I saw this happen to a couple of my teeth when I was a kid. You mentioned that this would usually cause the baby tooth to eventually fall out, so I was wondering why I needed my baby tooth to be pulled out until I read your statement about how this would be necessary if the adult tooth erupts somewhere else. Now that I think about it, I remember that I had my adult tooth erupt behind my baby teeth without them ever feeling loose, so now I can see why they had to be pulled out. Thanks for the information!

  7. My child is 6 years old.and both of her front teeth are loose one of them is really up and when she wiggles one they both move ,and her adult tooth is coming out behind the one going up,what should we do.?please help im afraid of taking to dentist and messing with a nerve.

  8. I’ve got shark teeth and it’s long and irritates my tongue since it’s on the top I have been to the dentist and none of my teeth are loose what should I do?

  9. Hi ,
    As above the same problem my son facing, he is having shark teeth age is 15, I went to Dr. he said have to wait for some time til 16 age if it will not come out have to pull out,
    Kindly advice .. thanks.

  10. I clearly remember having two sittings at the dentist where a mask came over my face and knocked me out and I had mad dreams, all to remove 11 of my shark teeth. I then had to live with a brace as my adult teeth were criss crossed and overlapping and very high up on my upper gums. My teeth had the appearance of long vampire teeth, being the highest on the gum and protruding.
    The dentist was very dedicated and eventually after what seemed like forever as a child, my teeth were teased and pulled down into a more even row and although not perfectly straight by any means, were passable, if difficult to clean properly because of some of the angles of the teeth.
    I believe its a much less traumatic experience than in the 70’s to have teeth extracted and there are more regulations than back then. I wouldn’t be afraid of going to a dentist just try to get a good NHS one that has good reviews. Technology has moved on from in my day, and NHS treatment can probably manipulate teeth into the perfect smile these days, without too many problems.

  11. My granddaughter’s dental xrays show that her adult teeth are not coming thru since her baby teeth are not coming out. We were told that the baby teeth would have to be pulled. My grandson had the same thing which I didn’t know about. She wil be 13 years old soon. Do we need to get them pulled? Thank you.

  12. Hi,
    This is shahriar, my 7 year old son has double teeth in 2 front teeth of lower jaw, those two front teeth are adult teeth ( newly grown after losing his baby teeth ), and 2 more new teeth are just approaching to grow behind those teeth. i m bit worried, do u please help me n inform me whether this phenomena is most common or not ?? waiting for your reply eagerly.

    Thank you.

  13. Donna Allan says:

    My 6 year old son has this now. His baby teeth when he was teething took ages to cut through, it was almost like they wanted to spend more time in the gum before they erupted. One of his baby teeth (top right fang) was missing until about 6 months ago – it stayed inside the gum for years and we thought it wasn’t there but the dentist assured us it was.
    Now his two front bottom teeth are being very stubborn and don’t want to fall out. His big teeth are behind the two baby ones. The baby ones are a bit wobbly but aren’t for budging.
    I’m sure they’ll come out in there own time.

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