Just like everything else about the human body, teeth can come in all different sizes.
You may have bigger-than-average teeth, a condition known as macrodontia, or you might have smaller-than-average teeth.
Microdontia of one or two teeth is common, but microdontia of all teeth is rare. It can occur without other symptoms, but it’s sometimes linked to genetic conditions.
There are several types of microdontia:
True generalized is the rarest kind of microdontia. It typically affects people who have a condition like pituitary dwarfism and results in a set of uniformly smaller teeth.
Someone with relatively large jaws or a protruding jaw might receive a diagnosis of relative generalized microdontia.
The key here is “relative,” since the size of the large jaw makes the teeth look smaller even though they’re not.
Localized microdontia describes a single tooth that’s smaller than usual or smaller compared to neighboring teeth. There are several subtypes of this type of microdontia, too:
- microdontia of the tooth’s root
- microdontia of the crown
- microdontia of the whole tooth
The localized version is the most common version of microdontia. Typically, it affects teeth located on the maxilla, or the upper jawbone.
The maxillary lateral incisor is the tooth most likely to be affected.
Your maxillary lateral incisors are the teeth right next to your top two front teeth. The shape of the maxillary lateral incisor may be normal, or it could be shaped like a peg, but the tooth itself is smaller than expected.
It’s also possible to have one smaller lateral incisor on one side and a missing permanent adult lateral incisor on the other side that never developed.
You may be left with a primary baby lateral in its place or no tooth at all.
The third molar or wisdom tooth is another type of tooth that’s sometimes affected, and it may appear much smaller than the other molars.
Most people only have an isolated case of microdontia. But in other rare cases, a genetic syndrome is the underlying cause.
Microdontia usually results from both inherited and environmental factors. The conditions associated with microdontia include:
- Pituitary dwarfism. One of numerous types of dwarfism, pituitary dwarfism can cause what experts call true generalized microdontia, since all the teeth seem to be uniformly smaller than average.
- Chemotherapy or radiation. Chemotherapy or radiation during infancy or early childhood before the age of 6 can affect the development of the teeth, resulting in microdontia.
- Cleft lip and palate. Babies may be born with cleft lip or palate if their lip or mouth don’t form properly during pregnancy. A baby can have a cleft lip, cleft palate, or both. Dental abnormalities are more common in the area of the cleft, and microdontia may be seen on the cleft side.
- Congenital deafness with labyrinthine aplasia, microtia, and microdontia (LAMM) syndrome. Congenital deafness with LAMM affects the development of the teeth and ears. People born with this condition might have very small, underdeveloped outer and inner ear structures, as well as very small, widely spaced teeth.
- Down Syndrome.
Research suggeststhat dental abnormalities are common among children with Down syndrome. Peg-shaped teeth are commonly seen with Down syndrome.
- Ectodermal dysplasias. Ectodermal dysplasias are a group of genetic conditions that affect the formation of skin, hair, and nails and can also result in smaller teeth. Teeth are commonly conical-shaped, and many may be missing.
- Fanconi anemia. People with Fanconi anemia have bone marrow that doesn’t produce enough blood cells, resulting in fatigue. They may also have physical abnormalities like short stature, eye and ear abnormalities, misshapen thumbs, and malformations of the genitalia.
- Gorlin-Chaudhry-Moss syndrome. Gorlin-Chaudhry-Moss syndrome is a very rare condition that’s characterized by premature closure of the bones in the skull. This causes abnormalities of the head and face, including a flat appearance to the middle part of the face and small eyes. People with this syndrome often experience hypodontia, or missing teeth, too.
- Williams syndrome. Williams syndrome is a rare genetic condition that can affect the development of facial features. It can result in features such as widely spaced teeth and a wide mouth. The condition can also cause other physical abnormalities such as heart and blood vessel issues, as well as learning disorders.
- Turner syndrome. Turner syndrome, also known as Ullrich-Turner syndrome, is a chromosomal disorder that affects females. Common characteristics include short stature, a webbed neck, heart defects, and early ovarian failure. It can also cause a shortening in the width of a tooth.
- Rieger syndrome. Rieger syndrome is a rare genetic condition that causes eye abnormalities, underdeveloped or missing teeth, and other craniofacial malformations.
- Hallermann-Streiff syndrome. Hallermann-Streiff syndrome, also called oculomandibulofacial syndrome, causes skull and facial malformations. A person with this syndrome might have a short, broad head with an underdeveloped lower jaw, among other characteristics.
- Rothmund-Thomson syndrome. Rothmund-Thomson syndrome shows up as redness on a baby’s face and then spreads. It can cause slow growth, thinning skin, and sparse hair and eyelashes. It can also possibly result in skeletal abnormalities and abnormalities of the teeth and nails.
- Oral-Facial-Digital syndrome. The subtype of this genetic disorder known as type 3, or Sugarman, syndrome can cause malformations to the mouth, including the teeth.
Microdontia may occur in other syndromes as well and is usually seen with hypodontia, which is fewer teeth than normal.
Teeth that are abnormally small or small teeth with wide gaps between them might not fit together correctly.
You or your child might be at higher risk for more wear and tear on your other teeth, or food may be easily get trapped between teeth.
If you’re experiencing any pain in your jaw or teeth, or noticing damage to your teeth, make an appointment with a dentist who can assess your teeth and determine if any treatment is needed. If you don’t already have a dentist, the Healthline FindCare tool can help you find one in your area.
Most of the time, localized microdontia doesn’t need to be fixed.
If your concern is aesthetic — that is, you want to mask the appearance of your microdontia and flash an even smile, a dentist can offer you some possible options:
Dental veneers are thin coverings usually made of porcelain or a resin-composite material. The dentist cements the veneer onto the front of your tooth to give it a more even, unblemished appearance.
Crowns are a step beyond veneers. Instead of a thin shell, a crown is more of a cap for your tooth and covers your entire tooth — front and back.
Sometimes, dentists have to shave down the tooth to prepare it for the crown, but depending on the size of your tooth, that might not be necessary.
This process is sometimes called dental bonding, or composite bonding.
The dentist roughens the surface of the affected tooth and then applies a composite-resin material to the surface of the tooth. The material hardens with the use of a light.
Once hardened, it resembles a regular, normal-sized tooth.
These restorations may also protect your teeth from the wear and tear that unevenly fitting teeth sometimes cause.
Many of the causes of generalized microdontia have a genetic element to them. In fact,
If anyone in your family has a history of the genetic disorders mentioned above, or anyone has smaller than usual teeth, you may want to tell your child’s physician.
However, if you have one or two teeth that appear smaller than normal, the teeth may have just developed that way with no underlying syndrome.
If you don’t have a family history but believe that some of your child’s facial features seem atypical or malformed, you might ask your child’s doctor to assess them.
The doctor may recommend a blood test and genetic testing to determine if your child might have a condition that causes other health concerns that may need diagnosis and treatment.
A small tooth might not cause any problems or pain for you at all. If you’re concerned about the esthetics of the teeth or how they fit together, you might want to see a dentist.
A dentist can discuss possible solutions like veneers or crowns that can fix or treat the issue.
In some cases, microdontia can also be a sign of a larger health issue that may need addressing. If you notice other unusual signs or symptoms, discuss the issue with a doctor or your child’s pediatrician.