Everyone knows that you have one set of baby teeth and one set of permanent teeth. Or do you? Certain conditions can cause dental anomalies – babies born with teeth already in place, babies who cut teeth within days or weeks of being born, and babies who have fewer teeth than expected, or don’t develop teeth at all!
Supernumerary Teeth (Hyperdontia)
Hyperdontia is a condition where the body produces more teeth than normal. This condition can cause the formation of extra deciduous teeth (baby teeth – .8%) or more likely, extra permanent teeth (2.1%). Supernumerary teeth are more common in males than females, and they can appear anywhere in the mouth and may or may not actually erupt. That doesn’t mean they don’t cause trouble, though!
Supernumerary teeth can cause crowding of the other teeth, but only rarely do they prevent other teeth from erupting. Commonly, they cause neighboring teeth to twist to accommodate the lack of space. Occasionally, supernumerary teeth have been known to resorb the roots of neighboring teeth. When this occurs, the supernumerary teeth must be removed as soon as possible to avoid the need for significant dental assisting help for the surrounding teeth.
No one understands what causes supernumerary teeth to form, but defects in the development of tooth buds that may cause the tooth bud to split are suspected. Supernumerary teeth feature in several different genetic conditions that impact craniofacial development.
Missing Teeth (Hypodontia)
Where hyperdontia causes the formation of too many teeth, hypodontia causes the formation of too few teeth. In most cases of hypodontia, as many as six teeth are missing from the upper jaw, also known as the maxilla. In cases where more than six teeth are missing (having never been formed) the condition is referred to as oligodontia, and in rare cases, no teeth form at all. This condition is called adontia.
Hypodontia affects primary teeth in less than 1% of the population, and the condition occurs about equally in males and females. When hypodontia affects permanent teeth, females are affected about four times as often as males are. The most common absent teeth are wisdom teeth. More than a third of adults don’t form these extra molars.
There are no specific known causes of hypodontia, but some experts have speculated that some genetic conditions, the age of the mother, and low birth weights may play a role in hypodontia. Scientists have also noticed a correlation between hypodontia in women and a certain type of ovarian cancer. Women who have hypodontia are more than eight times more likely to develop epithelial ovarian cancer than women whose teeth form normally. While there is no likelihood that hypodontia causes ovarian cancer, it could be an indicator that ovarian cancer is a more likely outcome for a person with hypodontia.
Neonatal and Natal Teeth
In an oddity that would likely frighten most new parents, a small number of babies are born each year with teeth that have already erupted (natal teeth), or that erupt within days or weeks of being born (neonatal teeth). Normally, primary teeth erupt in infants between the ages of 6 and 14 months.
Natal and neonatal teeth aren’t all that rare, with experts estimating that about 1 in every 3,000 infants have teeth at birth or produce teeth shortly after being born. Most commonly, the bottom incisors erupt prior to birth. Less commonly, teeth erupt shortly after birth. In most cases, the teeth are part of an otherwise normal set of primary teeth, however it is not uncommon for natal teeth to have a weak or non-existent root structure and other malformations. In about 10% of cases, natal teeth are supernumerary and are followed by another set of primary teeth!
Sarah Cowl is a freelancer by heart, but she loves to read and hang out with her friends on her freetime. As a journalism graduate her passion is writing. This article was written by a guest author. Would you like to write for us?