Hyperdontia: Definition, Causes, and Treatment

What is Hyperdontia?

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.

Make sure to tell your general dentist if hyperdontia causes:

• Pain or discomfort
• Difficulty chewing
• Difficulty brushing or flossing
• Swelling in the mouth

Signs of Hyperdontia 

The main sign of hyperdontia is the development of additional teeth directly behind or close to your permanent teeth. 

Supernumerary teeth can grow alone or in multiples. They can also appear in different areas of the mouth, such as:

• In front or behind adult teeth
• In one or both sides of the mouth
• In the upper or lower jaw

What Does Hyperdontia Look Like?

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.

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 and appears as several small, tooth-like growths near each other.
• Complex odontoma —  Rather than a single tooth, an area of tooth-like tissue grows in a disordered group.
• Conical or peg-shaped —the tooth is wide at the bottom and narrows toward the top, giving the appearance of a cone or peg.

How is Hyperdontia Diagnosed?

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 imaging called a cone beam computerized tomography (CBCT) scan. This will give them a more detailed look at your mouth, jaw, and teeth.

Treatment for Hyperdontia

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:

• Have an underlying genetic condition leading the extra teeth to develop
• Cannot chew properly
• Feel pain or discomfort
• Have difficulties brushing or flossing your teeth
• Feel uncomfortable or self-conscious 
• Can’t get other types of dental treatment like braces
• Get cysts or damage to the roots of nearby teeth
• Cannot grow teeth properly
• Suddenly get them (spontaneous eruption)

If the additional teeth only cause mild discomfort, your dentist may suggest taking nonsteroidal anti-inflammatory drugs (NSAIDs). These drugs include ibuprofen to reduce the pain of overcrowding.

If the surrounding teeth are crooked or affected, extra dental and orthodontic treatment can fix these issues.

What to Expect After Tooth Removal

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. 

Due to swelling and bruising, you won’t be able to open your mouth completely. This is most prevalent on 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. They will also recommend you abstain from work or school.

Outlook for Tooth Removal

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. 

Removing extra teeth can reduce the risk of dental complications in the future. Furthermore, once the additional tooth is removed, any discomfort usually stops.

Risks of Untreated Hyperdontia

Hyperdontia is not usually painful. However, the additional teeth may increase pressure on your jaw and gums, leading to swelling and soreness.

Most supernumerary teeth cause risks and complications. These risks include:

• Diastema, a gap between teeth
• Overcrowding
• Crooked teeth
• Gum disease
• Pain
• Inflammation or infections, like gingivitis or periodontitis
• Delayed eruption of permanent teeth
• Impaction of permanent incisors
• Abnormal root formation in nearby teeth
• Cystic lesions or tumors around the teeth
• Baby teeth not erupting in time

It’s essential to remove supernumerary teeth if they affect your dental hygiene or other teeth.

What are the Chances of Having Hyperdontia?

In permanent teeth, the prevalence of hyperdontia varies from 0.1% to 3.8%. In baby teeth, the prevalence is 0.3% to 0.6%.¹

Two additional teeth only occur in 12% to 23% of hyperdontia cases. The chances of having more than two extra teeth are fewer than 1% of all cases.

As many as 98% of supernumerary teeth are in the upper jaw. When hyperdontia develops in adult teeth, it’s twice as prevalent among males than females.

What Causes Hyperdontia?

The cause of hyperdontia remains unclear. However, it is believed that hyperdontia is associated with various hereditary conditions. These conditions include:⁵

• Gardner’s Syndrome —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, painful muscles and joints, and scoliosis.
• Fabry disease — inability to sweat, painful hands and feet, a blue or red skin rash, and abdominal pain.
• Cleft palate and lip — congenital birth defects result in an opening in the roof of the mouth or upper lip.
• Cleidocranial dysplasia —abnormal growth of the skull and collarbone. 
• Ellis van Creveld syndrome — a rare disorder that causes short limb dwarfism and additional fingers and toes.
• Nance-Horan syndrome — causes dental abnormalities and congenital cataracts that result in poor vision.
• Rubinstein-Taybi syndrome — causes distinctive facial features, short stature, and intellectual disability, as well as problems with the teeth, eyes, heart, and kidneys.
• Trichorhinophalangeal syndrome — Bone and joint malformations, distinctive facial features, and abnormalities of the skin, hair, and teeth.

Other potential causes of hyperdontia include environmental factors and overactivity of the dental lamina during tooth growth. 

Where Do Extra Teeth Usually Develop?

There are also specific locations of the mouth where supernumerary teeth tend to develop:

• Paramolar — develops in the back of your mouth, close to one of your molars.
• Distomolar — grows in line with your other molars instead of around them.
• Mesiodens — develops behind or around your incisors. This is the most prevalent type of extra tooth in people with hyperdontia.

Summary

Hyperdontia is a dental condition that causes more teeth to grow in the mouth. While the cause of hyperdontia isn’t fully understood, it could be caused by genetic or environmental factors.

Extra teeth can appear in different areas of the mouth. They can appear alone or in multiples and take on different shapes.

Hyperdontia is relatively harmless but can cause complications, discomfort, and gum disease. Dentists may need to remove the extra teeth. However, in other cases, it isn’t necessary.