Are Short Teeth Common?
Similar to virtually all aspects of the human body, teeth come in various shapes and sizes. While some patients with macrodontia have teeth which are larger than normal, others may have microdontia or teeth which are smaller than normal. People may simply describe this phenomenon as the patient having short teeth. It is relatively common for patients to have microdontia of one or two teeth, however, microdontia of all the teeth is quite rare. The condition can exist without other symptoms, but is commonly connected with certain genetic conditions or syndromes. There are three main types of microdontia which are summarized below.
True generalized microdontia is the rarest form of the condition and results in all of the teeth being smaller than normal. This is commonly found in patients with another condition such as pituitary dwarfism.
Relative generalized is also not very common and may appear that the patient has smaller teeth, however the patient actually has a larger or protruding jaw. The term “relative” is used because the large jaw gives the perception that the teeth are smaller, even though they are normal.
Localized microdontia occurs when one or two teeth are smaller than normal or smaller than the adjacent teeth. This type of microdontia contains the following subtypes:
- microdontia of the root
- microdontia of the crown
- microdontia of the entire tooth
Localized microdontia is the most common form and typically impacts teeth located in the upper jaw. It is common for the maxillary lateral incisor to be impacted. The maxillary lateral incisors are the teeth which are next to the front teeth in the top jaw. The maxillary lateral incisor’s shape may be normal or shaped like a peg, however, the actual tooth is smaller in size.
In some cases, the patient will have one lateral incisor which is smaller and a lateral incisor on the other side which never developed or erupted. The patient may have a primary or baby lateral or the tooth may be missing completely. It is also common for the third molar or wisdom tooth to be affected by the condition and appear much smaller compared to the other molars.
Causes
Most patients have an isolated case of microdontia, however, it is possible for a genetic syndrome to be the underlying cause. Microdontia is often the result of both inherited and environmental factors. Conditions which are commonly associated with microdontia include the following:
- Pituitary dwarfism can cause true generalized microdontia, meaning all the teeth are smaller than average.
- Chemotherapy or radiation which is administered during infancy or early childhood can impact how the teeth develop and result in microdontia.
- Babies who are born with cleft lip or palate often have microdontia.
- Congenital deafness with labyrinthine aplasia, microtia, and microdontia (LAMM) syndrome affects the development of the ears and teeth. People with this condition often have small, underdeveloped ear structures and extremely small teeth with wide gaps.
- Patients with Down syndrome often encounter dental abnormalities such as small, peg-shaped teeth.
- Other conditions which are less common include: Ectodermal dysplasias, Fanconi anemia, Gorlin-Chaudhry-Moss syndrome, Williams syndrome, Turner syndrome, Rieger syndrome, Hallermann-Streiff syndrome, Rothmund-Thomson syndrome, and Oral-Facial-Digital syndrome
Microdontia can occur on its own or in combination with hypodontia, a condition which results in fewer than normal teeth.