Children lose all 20 of their baby teeth, usually starting around age six and finishing somewhere between ages 11 and 13. The lower front teeth almost always go first, and the back molars are the last to shed. The process follows a broadly predictable pattern, but the timing can shift by a year or more depending on a child’s sex, body weight, genetics, and nutrition, so there is a wide window of “normal” that catches many parents off guard.
Which Teeth Fall Out and in What Order
A child’s 20 primary teeth arrive in a rough sequence during infancy and toddlerhood, and they leave in a similarly organized way. The general pattern moves from front to back, with the lower jaw slightly ahead of the upper jaw at most stages. Here is the typical order and the age ranges most children experience:
- Lower central incisors: the two bottom-front teeth, usually the first to go, around ages 6 to 7.
- Upper central incisors: the two top-front teeth, typically around ages 6 to 7, close behind.
- Upper lateral incisors: the teeth flanking the top-front pair, around ages 7 to 8.
- Lower lateral incisors: the teeth flanking the bottom-front pair, around ages 7 to 8.
- Upper first molars: around ages 9 to 11.
- Lower first molars: around ages 9 to 11.
- Upper and lower canines: the pointed “eye teeth,” around ages 9 to 12.
- Lower second molars: around ages 10 to 12.
- Upper second molars: the very last to go, around ages 10 to 12.
There is some variability in the middle of this sequence. The canines and premolars of the permanent set can jostle for position, and research on eruption sequences shows that the exact order of the premolars and canines can swap from child to child without signaling any problem.1PubMed. Polymorphisms in eruption sequence of permanent teeth in American children The front teeth and the first permanent molars, though, are reliably first in line. Boys and girls sometimes show slightly different sequencing in the upper jaw, with the first permanent molar tending to beat the central incisor in girls but not always in boys.2PubMed Central. Changes in the Sequence of Eruption of Permanent Teeth; Correlation between Chronological and Dental Age and Effects of Body Mass Index of 5-15-year-old Schoolchildren
Why Baby Teeth Fall Out at All
The process looks simple from the outside: a tooth gets wiggly, it dangles, and eventually it drops. Underneath the gum, though, there is an active biological demolition project. Specialized cells gradually dissolve the roots of the baby tooth in a process called root resorption. These cells are closely related to the cells that break down and remodel bone throughout the body, and they are triggered into action by chemical signals from the developing permanent tooth sitting below.3Journal of Oral Science. Physiologic root resorption in primary teeth: molecular and histological events The permanent tooth’s surrounding tissue essentially tells the baby tooth’s root to dissolve and make way.
As the root shortens, the baby tooth loses its anchor in the jawbone. The crown, which is the visible part, remains intact, so the tooth looks normal even as its foundation is being eaten away. Eventually, so little root is left that only the gum tissue holds the tooth in place, and everyday forces like chewing or tongue pressure are enough to pop it free.
There is another change happening at the same time that most people never notice. The nerve fibers running through the baby tooth’s inner pulp start to break down progressively as the root resorbs. This nerve degeneration follows a pattern similar to what happens when a nerve is severed elsewhere in the body, and it is likely why loose baby teeth rarely cause much pain during those final wiggly weeks.4PubMed. Axonal Degeneration in Dental Pulp Precedes Human Primary Teeth Exfoliation By the time the tooth is ready to come out, the pulp is largely desensitized.
Why Some Kids Lose Teeth Earlier or Later Than Others
The age ranges listed above are averages. A child who loses a first tooth at five or who still has all baby teeth at seven can be perfectly normal. Several factors push the schedule earlier or later.
Sex plays a small but consistent role. During infancy, boys tend to get their first baby teeth slightly earlier than girls, with the difference averaging about a week.5PubMed Central. Maternal and early life factors of tooth emergence patterns and number of teeth at one and two years of age That pattern flips later in childhood. After about age five or six, girls begin to pull ahead in dental development and tend to shed baby teeth and erupt permanent teeth earlier than boys.6PubMed. Sexual differences in dental development and prediction of emergence The gap is not huge, but it is consistent enough that a girl who loses teeth a bit earlier than her male classmates is following a well-established pattern.
Body weight has a more pronounced effect. Children with higher body mass index tend to erupt permanent teeth earlier. One large study found that obese children had, on average, about one and a half more erupted teeth than non-obese children of the same age and sex.7PubMed Central. The Association Between childhood Obesity and Tooth Eruption Separate research found that overweight and obese children showed a dental age acceleration of roughly a year and a half compared to their chronological age.8PubMed. Childhood obesity and dental development On the other end, underweight children show a distinct delay in eruption ages.9The Saudi Dental Journal. Association of Body Mass Index and Chronology of Tooth Eruption in Children visiting a Dental Hospital in UAE: A Cross-sectional Study The mechanism likely involves hormones and growth factors that are more abundant in children with higher body fat, accelerating the maturation signals that drive root resorption and permanent tooth eruption.
Genetics, nutrition, and even prematurity at birth can further nudge the timeline, which is why pediatric dentists rarely worry about a tooth that is a year “late” unless there are other signs of a problem. If a child reaches age eight without losing any teeth, an X-ray can confirm whether permanent teeth are forming normally below the surface.
When the New Tooth Grows Behind the Old One
Sometimes a permanent tooth does not push straight up under the baby tooth. Instead, it erupts behind it, usually on the tongue side, creating a double row that parents often call “shark teeth.” This looks alarming but is one of the most common minor dental surprises in childhood. One clinical study of children at a dental hospital found that about 7 percent of young patients presented with this two-row appearance, most commonly around age six or seven, and roughly three-quarters of the cases occurred in the lower jaw.10Academia.edu / IOSR Journal of Dental and Medical Sciences. “Shark Teeth” Like Appearance among Paediatric Dental Patients
In most cases, the baby tooth falls out on its own within a few weeks once the permanent tooth creates enough pressure to finish off the root resorption. If the baby tooth refuses to budge after the permanent tooth is well in, a dentist can extract it with minimal fuss. The tongue then tends to push the permanent tooth forward into its proper spot over time. Orthodontic intervention is rarely needed for this specific issue unless the spacing is very tight.
When Baby Teeth Refuse to Leave
The opposite problem, a baby tooth that will not shed on schedule, is less common but more likely to need professional attention. One cause is ankylosis, a condition where the root of the baby tooth fuses directly to the surrounding bone. Histological studies have found ankylosis in nearly all clinically “submerged” baby molars, those that appear to sink below the biting surface of their neighbors as the child grows.11Archives of Oral Biology. Submerged human deciduous molars and ankylosis What happens is that the fused tooth stays locked at its original height while the teeth on either side continue to erupt upward, making the ankylosed tooth look like it is sinking.
Ankylosed baby molars can cause problems beyond just sticking around too long. Neighboring teeth may tilt toward the gap in the bite line, and the opposing tooth may over-erupt into the space, both of which can set the stage for crowding when permanent teeth try to come in.12PubMed Central. Submerged and Impacted Primary Molars Treatment depends on severity. Mildly submerged teeth are sometimes monitored with regular X-rays. Severely submerged ones often need to be extracted surgically so the permanent successor can erupt normally.13PubMed Central. Management of a severely submerged primary molar: a case report
Another reason a baby tooth might hang on is the absence of a permanent replacement underneath. When the permanent tooth that is supposed to trigger root resorption simply never developed, the baby tooth has no biological signal to dissolve its root. These retained baby teeth can sometimes last well into adulthood, though they tend to be more fragile over the long haul and may eventually need a dental implant or bridge as a replacement.
How Losing a Baby Tooth Too Early Can Cause Problems
Baby teeth are not just placeholders waiting to be discarded. They serve active roles in chewing, speech development, and jaw growth, and they physically hold open the space that the permanent tooth will eventually need.14Expanded Science: Innovation and Research – 2° Edição. PREMATURE LOSS OF PRIMARY TEETH DUE TO DENTOALVEOLAR TRAUMA AND THE IMPORTANCE OF SPACE MAINTAINERS AS PREVENTIVE TREATMENT When a baby tooth is lost well before its time, whether from decay, trauma, or extraction, the neighboring teeth can drift into the empty space. That drift narrows the gap, potentially leaving the permanent tooth with nowhere to go. It may then come in crooked, get stuck in the bone, or crowd its neighbors.
Dentists manage this risk with space maintainers, small metal or acrylic appliances cemented to an adjacent tooth that hold the gap open until the permanent tooth is ready. They are especially common after early loss of a baby molar, since those spaces are large and the permanent premolars that fill them may not arrive for several more years. A space maintainer is a low-tech fix, but skipping it after premature loss of a molar often means orthodontic work later.
Trauma to Baby Teeth and What It Means for Adult Teeth
Young children fall. A lot. And the upper front baby teeth bear the brunt of it because they are the most exposed. When a baby tooth takes a hard hit, the concern goes beyond the tooth itself. The developing permanent tooth sits just a few millimeters away inside the bone, and a strong enough impact can disturb its formation. A retrospective study tracking traumatized baby teeth found that about a third of them resulted in some form of developmental change in the permanent successor.15PubMed Central. Impact of Traumatic Injuries to Primary Teeth on the Development of Permanent Dentition: Findings From a Retrospective Cohort The majority of those changes were mild, with enamel discoloration being the most common. Intrusion injuries, where the baby tooth gets shoved up into the gum, carried the highest risk of affecting the permanent tooth.
A case report following a child for four years after a baby tooth injury showed that the permanent incisor came in with a visible enamel opacity, a white or yellowish patch on the surface.16PubMed Central. Dental trauma in primary dentition, its effect on permanent successors and on Oral Health-Related Quality of Life: a 4-year follow-up case report These cosmetic marks are usually permanent but do not weaken the tooth structurally. More severe trauma can occasionally cause the permanent tooth to form with an abnormal shape, a pitted surface, or a dilacerated root (a root that bends sharply). Because the window of vulnerability is highest when the permanent tooth crown is still mineralizing, injuries to baby teeth in children under about age three tend to carry the greatest risk of visible sequelae.
Baby Teeth Are Built Differently
If you have ever noticed that baby teeth look brighter and whiter than adult teeth, you are not imagining it. Baby teeth have thinner enamel with a higher organic content, which makes them appear more opaque and white compared to the slightly translucent, yellowish cast of permanent enamel.17ScienceDirect. Mapping the structure, composition and mechanical properties of human teeth That thinner enamel is also softer and more prone to fracture, which is one reason cavities in baby teeth can progress faster than in adult teeth. The pulp chamber, the nerve-filled center of the tooth, is proportionally larger in baby teeth as well, so a cavity does not have to penetrate as far before it reaches the nerve and causes pain or infection.
These structural differences are why pediatric dentists emphasize treating cavities in baby teeth promptly, even though the teeth are “going to fall out anyway.” A deep cavity in a baby molar that still has years of service ahead of it can abscess, damage the permanent tooth bud beneath it, and trigger exactly the kind of premature loss that leads to spacing problems.
What Kids Actually Feel When They Lose a Tooth
Losing a first tooth is a milestone that carries real emotional weight for children. Research examining parents’ reports of their children’s emotional reactions found that responses varied widely and were influenced by cultural context. Children whose parents came from non-Western cultural backgrounds tended to report more positive emotions around losing their first tooth compared to children in Western countries.18PubMed Central. Children’s Emotions Upon the Shedding of the First Primary Tooth From Parents’ Perspective The researchers suggested that cultural rituals and the significance parents attach to the event shape how children experience it. In cultures where tooth loss is celebrated with specific customs, children may feel excitement and pride. Where the event is treated more matter-of-factly, anxiety or ambivalence can dominate.
For anxious children, the sensation of a loose tooth can be distressing, even though the biological desensitization of the nerve described earlier means there is often less pain involved than the child fears. Framing the experience positively, whether through a tooth fairy tradition, a rooftop-throwing custom, or simply enthusiastic acknowledgment, can make a meaningful difference. Pediatric dentists sometimes note that children who have had negative dental experiences, like an early extraction due to decay, approach natural tooth loss with more apprehension.
Stem Cells in Baby Teeth
An area of genuine scientific interest that has also spawned a niche commercial industry involves the stem cells found inside baby teeth. The soft pulp tissue at the center of a tooth contains multipotent stem cells, cells that can develop into several different tissue types. The discovery of viable stem cells in dental pulp nearly two decades ago led to the emergence of “tooth banks,” services that collect a child’s naturally shed baby teeth, extract the stem cells, and store them in cryogenic facilities for potential future medical use.19PubMed Central. Banking on teeth – Stem cells and the dental office
The appeal is straightforward: every child loses teeth, the collection is painless and non-invasive, and the cells are a genetic match for the child who might someday need them.20PubMed. Banking stem cells from human exfoliated deciduous teeth (SHED): saving for the future The reality, though, is that clinical applications for dental stem cells remain largely experimental. Research has explored their potential in bone regeneration, nerve repair, and treatment of certain autoimmune conditions, but no mainstream therapy currently relies on banked baby-tooth stem cells. Parents considering tooth banking should weigh the cost of storage against the uncertainty of whether a proven therapy will emerge within their child’s lifetime. The science is real, the cells are genuinely useful in research, but the clinical payoff is still speculative.
If you do want to preserve a tooth’s stem cells, timing and handling matter. The tooth needs to be collected soon after it falls out, kept moist, and shipped to the banking facility quickly, because the cells inside the pulp begin to degrade once the blood supply is cut off. A tooth that has been sitting on a nightstand for a week under a pillow is unlikely to yield viable cells. Most tooth-banking services provide a collection kit with a transport medium designed to keep cells alive during shipping.