Hyperdontia is a dental condition that causes too many teeth to grow in the mouth. These additional teeth are sometimes called supernumerary teeth. One or more supernumerary teeth may grow in one or more locations in the mouth.
Supernumerary teeth can develop anywhere in the mouth's curved areas where the teeth attach to the jaw. This location is known as the dental arches.
The 20 teeth that grow during childhood are known as primary or deciduous teeth. The 32 adult teeth that replace primary teeth are permanent. Overcrowding of the teeth resulting from hyperdontia can make your permanent teeth appear crooked.
In permanent teeth, the prevalence of hyperdontia varies from 0.1 to 3.8 percent. In baby teeth, the prevalence is 0.3 to 0.6 percent.
If an additional tooth is visible, your dentist may describe it as erupted. If it is hidden under the gum line, they may describe it as impacted. Most supernumerary teeth are single and impacted.
Two additional teeth only occur in 12 to 23 percent of hyperdontia cases. In fewer than one percent of all cases, there are more than two extra teeth. As many as 98 percent of supernumerary teeth are in the upper jaw.
When hyperdontia develops in adult teeth, it is twice as prevalent among males compared with females.
Hyperdontia is not usually painful. However, the additional teeth may place pressure on your jaw and gums, leading to swelling and soreness.
There are various shapes that supernumerary teeth can take, including:
Supplemental — a supplemental tooth is shaped similarly to the tooth it grows near.
Tuberculate — the tooth features a tube or barrel-like shape.
Compound odontoma — instead of a single tooth growing, an area of tooth-like tissue develops.
Conical or peg-shaped —the tooth is wide at the bottom and narrows out toward the top, making it appear sharp.
There are also specific locations of the mouth that supernumerary teeth tend to develop:
Paramolar — an extra tooth develops in the back of your mouth, close to one of your molars.
Distomolar — an additional tooth grows in line with your other molars, instead of around them.
Mesiodens — an extra tooth develops behind or around your incisors, which are the four flat teeth at the front of your mouth for biting. This is the most prevalent type of extra tooth in people with hyperdontia.
The cause of hyperdontia remains unclear. However, it is believed that hyperdontia associates with various hereditary conditions.
These conditions include:
Gardner’s Syndrome — this is a rare genetic condition that leads to skin cysts, skull growths, and colon growths.
Ehlers-Danlos Syndrome — an inherited disease that results in loose joints that easily dislocate, easily bruised skin, sore muscles and joints, and scoliosis.
Fabry disease — this syndrome leads to an inability to sweat, painful hands and feet, a blue or red skin rash, and abdominal pain.
Cleft palate and lip — these congenital disabilities result in an opening in the roof of the mouth or upper lip, difficulties eating or speaking, and ear infections.
Cleidocranial dysplasia — this condition causes abnormal growth of the skull and collarbone.
Other potential causes of hyperdontia include environmental factors and overactivity of the dental lamina during tooth growth. The dental lamina is an area of cells that initiate tooth germ formation, which forms teeth.
The main symptom of hyperdontia is the development of additional teeth directly behind or close to your permanent teeth.
The teeth may grow alone or in multiples in one or both sides of the mouth in the upper or lower jaws. Or, supernumerary teeth may grow in both the upper or lower jaws.
Hyperdontia is easy to diagnose if the supernumerary teeth have already grown. If they haven’t completely grown in, they will still show on a dental X-ray. Your dentist may also use a three-dimensional image called a cone beam computerized tomography (CBCT) scan for a more detailed look at your mouth, jaw, and teeth.
Some cases of hyperdontia don’t require treatment. However, other cases require the removal of the extra teeth.
Your dentist will likely suggest removing the additional teeth if you:
Make sure to tell your dentist about any feelings of pain, discomfort, weakness, or swelling in your mouth if you have hyperdontia.
If the additional teeth only cause you mild discomfort, your dentist may suggest taking nonsteroidal anti-inflammatory drugs (NSAIDs). These drugs include ibuprofen to reduce the pain of overcrowding.
If you have any teeth removed, you should expect some bleeding for a day or two. This bleeding is easily managed with a dental compress. If necessary, your dentist will also prescribe a painkiller. You should expect some limited ability to completely open your mouth due to swelling and bruising, too, especially the day following the procedure.
Within a week or two, the swelling should be gone entirely. Any stitches would have fallen out on their own. Your dentist will advise on the most appropriate foods and beverages to eat and drink, along with any recommendations to abstain from work or school.
Early diagnosis of hyperdontia leads to a better outlook for people with the condition. A dentist may be able to diagnose hyperdontia in children as young as two years. Once the additional tooth is removed, any discomfort usually stops.
If the surrounding teeth are crooked or affected, extra dental and orthodontic work can fix these issues.
Most supernumerary teeth cause risks and complications. These risks include:
If the supernumerary teeth are beginning to affect your dental hygiene or other teeth, it is essential to remove them as soon as possible. The removal of additional teeth can help prevent any long-lasting effects, like gum disease or crooked teeth.
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