Tooth Calendar Blog
Six-Year Molars: How to Brush the First Permanent Molars That Arrive Quietly
Around age 6, the first permanent molars quietly come in behind the baby teeth. Why they get mistaken for baby teeth, how to brush them, and sealant timing.
At a glance
- Around age six, new molars come in behind the last baby teeth
- Half-in molar? Angle the brush in from the side
- Once it's fully in, it's sealant time. Tell your dentist
As your child nears age seven, you may find yourself watching the front teeth, waiting for one to fall out. But often, before that happens, a new molar quietly comes up at the very back of the mouth without any tooth falling out. This is the first permanent molar, the one your child will use for life, often called the 6-year molar.
A lifelong molar that sneaks in at the back
Around age 6, the first permanent molars come up through the gum behind the last baby molars. There's one on each side, top and bottom, so four in all. Other permanent teeth come in where a baby tooth fell out, but these molars come in from empty gum, with no baby tooth lost. That's why parents and kids often don't notice a new tooth has arrived.
A common myth is thinking this molar is "a baby tooth that will fall out later." It looks about the same size, and you don't know when it came in, so it's easy to think so. But this is a permanent tooth that won't grow back. When these molars come in, your child's mouth enters the stage where baby teeth and permanent teeth are there together.
These molars carry most of the chewing load and become the anchor for where the other permanent teeth settle. Since they don't grow back and are used for life, protecting them from the start matters.
There are reasons a brand-new molar is prone to cavities. The chewing surface has deep grooves, and while it's halfway in, it sits lower than the baby teeth in front, so the brush skips right over it. Gum still covers part of it, so food easily gets stuck in that gap. When these molars come in can vary by more than half a year from child to child.
Check and brush all the way to the back like this
- In good light, have your child open wide and look at the gum behind the last baby molar.
- A white edge breaking through the gum is a new molar. Check both sides, top and bottom.
- After brushing the front teeth as usual, slide the brush in from the side, at the corner of the mouth, and brush the back molar on its own.
- Place the bristles on the chewing surface and gumline of the new molar and use short back-and-forth strokes. Opening too wide stretches the cheek and actually makes it harder to see, so having your child open just a little makes it easier to get the brush in.
- Use a pea-sized amount of fluoride toothpaste, and finish the bedtime brushing yourself.
- Once it's fully in, it's time for a sealant, so let your dentist know.
Kids this age want to brush on their own, but the back molars are the hardest spot for their hands to reach. Letting your child brush first and then going over just the back molars yourself cuts down on battles. Showing your child the new molar in a mirror and saying, "This is your new molar at the back. You'll use it for life, so let's brush it extra well," helps them take an interest too.
New molars don't come in all at once. They come up slowly, little by little. Peeking at the back about once a month to see how far they've come up helps you not miss the right time for sealants.
Frequently asked questions
How can I tell a baby tooth from a permanent one?
If it came in behind the last baby molar without any tooth falling out, it's a 6-year molar. If you're not sure, have the dentist check at the next visit.
Does it hurt when these molars come in?
As they break through the gum, your child may feel itchy or uncomfortable. If the gum is swollen and sore, trapped food may have caused inflammation, so clean it gently, and see the dentist if it doesn't settle.
When are sealants done?
Once the chewing surface has fully come up above the gum, it's time for a sealant. The whole chewing surface needs to be showing so it can be kept dry during the procedure. All four may not come in at once, so talk about the ones that are fully in first. If your child has a high cavity risk, the dentist may use a different, temporary protection (such as a glass ionomer sealant) even before the molar is fully in, so talk with the dentist once you see a new molar.
Only one side has come in so far. Is that okay?
It's common for the two sides to come in a little differently. But if only one side has come in after age 7, have it checked at a visit.
When to see a dentist
- There's still no sign of the back molars after age 7
- Only one side has come in after age 7
- Swollen, sore gums around a new molar don't settle
- The grooves of a new molar look brown or black
- A new molar is fully in, but you haven't talked about a sealant yet
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Sources
- ADA · Eruption Charts (2024)
- AAPD · Use of Pit-and-Fissure Sealants (2016)
The information in this article is for general educational purposes and does not replace professional dental care. Talk to a dentist about your child's condition.