A permanent tooth growing in a second row
Your child is six or seven, and a row of new teeth suddenly appears behind the lower front baby teeth. It looks wrong, and parents usually write to us the same evening. Let me reassure you straight away: this is very common — dentists half-jokingly call it “shark teeth” — and in most cases it resolves itself within a few weeks.
Why it happens
Normally a permanent tooth pushes upwards against the root of the baby tooth above it. Under that pressure the root gradually resorbs, the baby tooth loses its support and falls out, and the permanent tooth rises into exactly its place.
A second row forms when the permanent tooth travels not directly under the baby one but slightly behind it. It then passes the root without resorbing it: the baby tooth stays firmly seated and the new one emerges on the inner side.
Why the tooth travels off-course usually has no precise answer. Most often it is simply that child's anatomy. Another share of cases is explained by a shortage of room: permanent incisors are noticeably wider than baby ones, and in a narrow jaw the tooth looks for somewhere to come through.
It happens most often with the lower central incisors at six or seven, which account for the majority of cases. Less often with upper incisors, and more rarely still with canines at nine to eleven.
When it resolves on its own and when it does not
Usually it resolves. The tongue presses constantly on the new tooth from inside, while the baby tooth gradually loses support anyway. Within two to four weeks the baby tooth falls out, and over a few months the permanent one moves into place by itself. This works particularly reliably with lower incisors.
Worth waiting if: the baby tooth is even slightly loose; less than a month has passed; it concerns the lower central incisors; the child has no pain and can eat normally.
Not worth waiting if: the baby tooth is completely solid and does not move at all; more than six to eight weeks have passed with no change; the permanent tooth is already half-erupted while the baby one is still in place; the gum around it is inflamed or sore; chewing is uncomfortable; it involves the upper teeth, where resorption goes less readily.
The rule of thumb for parents is simple: loose means wait, solid means come in.
What the dentist does
First an examination and an X-ray. The image is not for drama: it shows how far the baby tooth's root has resorbed, at what angle the permanent tooth is travelling and whether there is room in the arch. Without it the decision is guesswork.
If the baby root has already resorbed — we simply keep waiting, sometimes with a review in a month.
If the root is intact and the tooth is not going anywhere — the baby tooth is removed. It is short: anaesthetic gel, then an injection the child usually does not feel, and the tooth is out in a minute. After that the permanent tooth almost always moves forward on its own over a few months.
If there is not enough room in the arch — that is a matter for the orthodontist. Sometimes a plate is needed, sometimes observation until the rest of the teeth change is enough.
We are in no hurry to extract. Removing a baby tooth unnecessarily has its own cost: some of the space can be lost, leaving the permanent tooth more crowded. So the decision follows the X-ray, not the appearance.
An examination with a consultation is UAH 690; a treatment plan — UAH 1,000. Imaging, if needed, is charged separately.
Does this mean braces later
By itself, no. A second row at six is not a verdict and does not permanently “ruin” the bite. Most children with this situation develop normally afterwards.
But it is a reason to assess the room in the jaw. If the tooth travelled past the root because of crowding, that crowding is not going anywhere — it will show up later when the canines erupt. By then it becomes dental crowding, and dealing with it takes longer.
So at six or seven we recommend a one-off orthodontic check. At that age the jaws are still growing and some problems are solved without braces — by expansion, a plate, or holding space. Five years later the same problems cost more and take longer.
And the reverse: if the orthodontist says there is plenty of room and the cause was purely the direction of eruption, you simply stop worrying — which is also a result.
What you can do at home
Let your child wiggle the baby tooth with their tongue. It is the most useful thing available, and it is free. Tongue pressure genuinely speeds the process up.
Offer firm food. Apple, carrot, cucumber — chewing helps the baby tooth loosen. But only if it is already loose and painless.
Brush that area more carefully. Two rows of teeth create a space a brush reaches poorly, and plaque builds up there fast. The gum between the rows inflames easily.
Do not pull or extract at home. A baby tooth with an unresorbed root sits firmly, and trying to pull it out at home ends either in nothing or in a fractured root left in the gum.
Do not panic in front of your child. Children this age are sensitive to a parent's reaction, and “oh, what's that!” frightens more than the situation itself.
Frequently asked questions
Why is the permanent tooth growing behind the baby one?
It erupts slightly behind rather than directly beneath, so it does not press on the baby tooth's root. The root does not resorb, the baby tooth holds on, and the new one comes through on the inner side.
Does it resolve on its own?
In most cases yes, particularly with lower incisors. The tongue presses on the new tooth, the baby tooth falls out within two to four weeks, and the permanent one settles into place over a few months.
How long should we wait before seeing a dentist?
If the baby tooth is even slightly loose, wait. If it is completely solid, or more than six to eight weeks have passed with no change, come in.
Does the baby tooth have to be removed?
Not always. The decision follows the X-ray: if the root has resorbed, we keep waiting; if it is intact and the tooth is going nowhere, it is removed. Unnecessary extraction has its own cost — some space can be lost.
Does removing such a tooth hurt?
Usually not. The gum is numbed with gel first, then an injection the child most often does not feel. The procedure itself takes about a minute.
Does this mean braces in future?
Not by itself. But it is a reason to assess whether there is enough room in the jaw: if the tooth travelled off-course because of crowding, that will show up later when the canines erupt.
Will the permanent tooth straighten after the baby one is removed?
Almost always, over a few months: the tongue and lips gradually bring it into line. If room is short, an orthodontist may be needed.
Can we help the tooth fall out at home?
Yes, safely: let your child wiggle it with their tongue and offer firm food if it is already loose. Pulling is best avoided — the root can fracture and stay in the gum.
Which teeth does this affect most often?
The lower central incisors at six or seven. Less often the upper incisors, and more rarely the canines at nine to eleven — where the situation is more complex and waiting is not advisable.
Restorative dentistry and paediatric appointments at Houston clinic. Prevention, helping children adapt to treatment, treatment of baby teeth.
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The dentist will look at the X-ray and say whether waiting is enough or the baby tooth should come out. A consultation is UAH 690; with a treatment plan — UAH 1,000.
Or book by phone 067 478 88 78
Book an examination for your child
The dentist will look at the X-ray and say whether waiting is enough or the baby tooth should come out. A consultation is UAH 690; with a treatment plan — UAH 1,000.
Book now