If your child’s permanent teeth are taking longer to arrive than you expected, the most likely explanation is that their timeline simply runs behind average. Kids grow teeth on their own schedule, and a difference of six months to a year from the textbook chart is common and rarely a problem.
Sometimes there is a real reason. The baby tooth above it may be refusing to loosen, the permanent tooth may be stuck under the gum, there may not be enough room in the jaw, or the tooth may never have formed at all. Each has a different fix, and the only way to tell them apart is with an exam and an X-ray.
At Children’s Dental Center, this is one of the most common worries parents bring to us. Below we cover normal eruption timing, the reasons a permanent tooth might be delayed or missing, when it is worth having your child looked at and what treatment looks like.
When permanent teeth normally come in
Permanent teeth arrive over about six years, starting around age six and finishing in the early teens. Here is the general order. Treat these as guidelines rather than deadlines.
- Ages 6 to 7 – the first permanent molars come in behind the baby teeth, and the lower front baby teeth are usually the first to go
- Ages 7 to 8 – the upper front teeth
- Ages 7 to 9 – the lateral incisors, meaning the teeth on either side of the front teeth
- Ages 9 to 12 – the canines and first premolars
- Ages 10 to 12 – the second premolars
- Ages 11 to 13 – the second molars
- Ages 17 to 21 – the wisdom teeth, if they come in at all
Most kids lose their last baby tooth by twelve or thirteen. Girls often run a few months ahead of boys, and a child who got their first baby teeth late as an infant tends to lose them late too. Once a baby tooth falls out, the permanent tooth underneath usually shows up within a few weeks to a few months. A gap that stays empty past six months is worth having us look at.
Baby teeth that won’t fall out
An over-retained baby tooth is one that stays put long after it should have loosened. Normally the permanent tooth pushes up from below and dissolves the root of the baby tooth as it rises, so the baby tooth gets wobbly and falls out. When that process stalls, the baby tooth stays firmly anchored.
The version parents notice most is the permanent tooth coming in behind the baby tooth instead of underneath it, usually in the lower front. Kids call these shark teeth. The baby tooth often loosens on its own within a few weeks, and a little wiggling helps. If it does not, we can remove it easily so the permanent tooth moves forward into position.
The other version is a baby tooth that stays with no permanent tooth appearing at all. That one needs an X-ray, because it points to a tooth that is stuck, a tooth angled the wrong way or a permanent tooth that never developed.
An impacted permanent tooth
An impacted tooth has formed normally but cannot break through. It might be blocked by another tooth, angled the wrong direction or simply lacking a clear path up through the gum. Upper canines are the most frequently impacted teeth after wisdom teeth. Occasionally the blockage is an extra tooth, since some children develop one more than the usual count and it sits directly in the path. These are almost always found on an X-ray rather than by looking in the mouth.
Impaction is very treatable, and catching it early makes treatment shorter. Depending on the case, we may create space with orthodontics so the tooth can come in on its own, remove whatever is blocking it or work with an oral surgeon to expose the tooth and attach a small bracket that gently guides it into place over several months.
Not enough room in the jaw
A permanent tooth needs somewhere to go. When the arch is crowded, a tooth can stay parked under the gum because the neighboring teeth have already taken the space.
This happens often when a baby tooth is lost early to decay or injury. Baby teeth hold space for the permanent teeth behind them, and when one disappears years ahead of schedule the surrounding teeth drift in to fill the gap. A space maintainer prevents that, which is why we recommend a visit any time a baby tooth comes out sooner than expected. Once crowding is the problem, treatment usually means creating space through expansion, orthodontics or the strategic removal of a tooth.
Ankylosis, when a baby tooth fuses to the bone
Ankylosis is a less familiar cause with a simple explanation. A baby tooth is normally held in the jaw by a thin ligament that lets it loosen and come out when the time is right. With ankylosis, part of the root bonds directly to the jawbone instead, so the tooth has nothing to loosen from.
The telltale sign is a baby tooth that looks sunken. The teeth and jaw around it keep growing while the fused tooth stays put, so over time it sits lower than everything beside it. Parents often describe it as a tooth sinking into the gum.
Ankylosed baby teeth are usually removed so the permanent tooth beneath can come in, often with a space maintainer placed afterward. If there is no permanent tooth underneath, the plan shifts toward the longer term options further down this page.
Congenitally missing teeth
Sometimes the permanent tooth is not delayed or stuck. It never formed in the first place. Most people end up with a full set of thirty-two permanent teeth, and when one never develops it is generally attributed to hypodontia, or congenitally missing teeth.
Hypodontia is one of the most common dental developmental differences there is, with up to 20% of adults missing at least one tooth. In most cases only one or two teeth are involved. It most often affects:
- The wisdom teeth – these sit at the very back of the mouth, and missing ones are so common that taking them out of the equation drops that 20% figure to around 5%
- The second premolars – the teeth directly in front of the molars
- The upper lateral incisors – the two teeth on either side of the upper front teeth
- The lower central incisors – the two front teeth in the lower jaw
Congenitally missing baby teeth are far rarer, affecting less than 1% of children, and when a baby tooth is missing there is usually no permanent tooth developing underneath it either.
What causes congenitally missing teeth
Tooth formation is complicated, and a lot of genetic signals have to be read correctly for it to finish. Most cases of hypodontia trace back to the dental lamina, a band of tissue under the gums where a tooth first begins to form. Research points to mutations in any of three genes that play a large role in tooth development, and when a mutation leaves the dental lamina missing, the tooth usually does not form either.
Hypodontia runs in families, so mention it at your child’s appointment if a parent, grandparent or sibling is missing a tooth. It can also be associated with certain medical conditions and genetic disorders, including Down syndrome and cleft lip and palate.
When to actually worry
Most delayed teeth turn out to be nothing. Here are the situations worth a call rather than a wait.
- A baby tooth came out more than six months ago and nothing has appeared in the space
- A tooth erupted on one side but the matching tooth on the other side still has not, six months later. Asymmetry is the clearest signal that something is off
- Your child is seven or older and has not lost a single baby tooth
- Your child is thirteen or older and still has baby teeth
- A baby tooth appears to be sinking below the level of the teeth around it
- There is pain, swelling or a firm bulge in the gum where a tooth should be coming through
Even without any of these, an evaluation around age seven is a good idea. That is roughly when enough permanent teeth are in for us to see how the rest of the mouth is developing, and when a panoramic X-ray can show whether every permanent tooth is present and heading the right direction.
How we find out what’s going on
An exam answers most of this quickly. We look at how your child’s teeth are aligned, how much crowding there is and how the bite fits together. Because so many things can hold a tooth back, X-rays are usually the deciding piece. They show whether the permanent tooth exists, where it is sitting and what is in its way.
If a permanent tooth is genuinely missing, there are three broad directions to go.
- preserve the baby tooth
- replace the missing tooth
- orthodontically close the space
These are not interchangeable. One of our doctors will determine the best choice based on the condition of your child’s teeth, their bite and the amount of crowding. A child’s jaw keeps growing until they are nearly an adult, so timing matters as much as method.
Treatment options for a missing permanent tooth
Orthodontics
One approach opens up space where a tooth should have erupted, especially when a neighbor has drifted into the gap, which makes room for an implant later. The other closes the space entirely by guiding the surrounding teeth into position, sometimes with light reshaping so they mimic the tooth that would normally sit there.
Implants
Implants are the ideal long term solution. They are strong, durable and natural looking. The catch is timing, since an implant can only go in once your child has finished growing. It does not shift with the jaw the way a natural tooth does, so placing one too early leaves it out of position later. Age alone is not a reliable indicator here.
Removable bridge
Often the right choice for a teen still waiting to finish growing. Despite the name it is really part denture, because it comes out, and part bridge, because it spans the gap. It gives the bite stability along with solid cosmetic results, and it feels much like the retainers we use after braces. Most kids adjust within a few days.
Traditional bridge
A traditional bridge does the same job but stays fixed, adhered directly to the teeth on either side of the gap. There are cases where that is preferred, though it is harder to keep clean and may require reducing healthy structure on the neighboring teeth to fit.
Composite bridgework
A composite bridge sits between the fixed and removable options. We shape a replacement tooth from bonding material and adhere it to the adjacent teeth, with no healthy structure removed. If an implant becomes the better choice later, it comes off easily. It has the same cleaning challenges as a fixed bridge, so a consistent brushing and flossing routine matters.
Frequently Asked Questions
When should I worry that my child’s permanent teeth haven’t come in?
Give it about six months after a baby tooth falls out before treating an empty space as a concern. Also worth checking if a tooth came in on one side but not the other, if your child is seven and has lost no baby teeth or if they are thirteen and still have some. An X-ray will show whether the permanent tooth is on its way.
Is it normal for a 7 year old’s baby teeth not to have fallen out?
It can be. Most kids lose their first baby tooth between five and seven, and some are simply on the later end of normal. If your seven year old has no loose teeth and no permanent teeth showing anywhere, including the molars at the back, book an evaluation. Seven is the age we recommend a first orthodontic checkup anyway.
What if my 12 year old still has baby teeth?
A stray baby tooth or two at twelve is not unusual, since the last ones typically come out around twelve or thirteen. What matters is whether a permanent tooth is developing underneath. If the baby tooth is not loose at all, or if it looks lower than the teeth around it, have it checked.
What causes a child to be missing adult teeth?
The usual cause is hypodontia, meaning the tooth never developed. It traces back to genetics affecting the tissue where a tooth first forms, and it frequently runs in families. Up to 20% of adults are missing at least one permanent tooth, most often a wisdom tooth, second premolar, upper lateral incisor or lower central incisor.
What happens if there’s no permanent tooth under a baby tooth?
The baby tooth often stays in place for years, since nothing is pushing it out. Depending on its condition and your child’s bite, we may preserve that baby tooth for as long as it lasts, close the space with orthodontics or plan a replacement once your child has finished growing.
Can a permanent tooth get stuck?
Yes. That is called an impacted tooth, meaning it formed but cannot break through the gum. It might be blocked by a crowded neighbor, angled the wrong way or held back by an extra tooth. Upper canines are the most commonly impacted teeth after wisdom teeth. Treatment ranges from creating space orthodontically to surgically exposing the tooth and guiding it in.
Will an X-ray show whether the permanent teeth are there?
It will. A panoramic X-ray shows every developing tooth in both jaws, including the ones still under the gum. It tells us whether a tooth exists, how far along it is, what angle it is coming in at and whether anything is blocking it.
Set your mind at ease with Children’s Dental Center
A permanent tooth that has not shown up is worth looking into, and in most cases the answer is reassuring. When it is not, the earlier we know, the more options your child has.
For children and teens dealing with delayed, impacted or missing permanent teeth, Children’s Dental Center offers personalized, compassionate care for families in Collierville, Midtown, Arlington and Germantown. Our state-of-the-art offices are fully equipped to diagnose what is happening and build a smile that works well and looks great. One of our experienced doctors and the rest of our team provide treatment options customized for every patient we see, so contact us today to schedule your child’s appointment. We have what it takes to give your child the smile they deserve!