Mesiodens (Extra Tooth Between the Front Teeth)

Types of Mesiodens

Mesiodens is classified by its shape and by whether it has erupted into the mouth.

By shape, there are three main forms:

• Conical — Small and peg-shaped, and the most common type. It usually has a fully formed root and may erupt into the mouth, though it frequently remains buried. A conical mesiodens most often causes displacement or rotation of the adjacent incisors rather than blocking their eruption entirely.
• Tuberculate — Barrel-shaped with multiple cusps and incomplete or abnormal root formation. It is more likely to remain buried, tends to sit closer to the roof of the mouth, and is more commonly associated with blocking the permanent incisors from erupting.
• Supplemental — Resembles a normal tooth in both size and shape. It is more often seen in the primary dentition and may go unnoticed if it blends in with the surrounding teeth.

By position, a mesiodens may sit upright, or it may be inverted — meaning the crown points upward toward the nasal cavity rather than downward toward the mouth. Inverted mesiodens are less likely to erupt on their own and can migrate deeper into the jaw over time if left untreated.

What Causes a Mesiodens?

The exact cause is not fully understood. The most widely supported explanation is hyperactivity of the dental lamina — the band of tissue from which teeth develop — leading to the formation of an extra tooth bud during development.

Genetic factors are also implicated. Mesiodens has been documented to run in families, and specific gene variants have been associated with its development in recent research. The pattern of inheritance does not follow a simple Mendelian model, and environmental factors are thought to interact with genetic susceptibility.

In the majority of cases, mesiodens occurs as an isolated finding with no underlying condition. In a smaller number of cases, it can be associated with syndromes such as cleft lip and palate, cleidocranial dysostosis, or Gardner's syndrome.

What Are the Symptoms and Signs?

Many people with a mesiodens have no symptoms at all. The condition is most commonly identified on a routine dental X-ray.

When signs are present, they may include:

• A permanent front tooth that is noticeably late erupting, or has not come through when the tooth on the other side already has
• A visible gap between the two upper front teeth that does not close as expected
• A front tooth that has erupted at an unusual angle or position
• A small tooth or unusual shape visible between or behind the front teeth
• Swelling or a firm lump in the gum above the front teeth, which may indicate cyst formation

In adults who were not diagnosed in childhood, a mesiodens is sometimes found when investigating unexplained crowding, a persistent midline gap, or discomfort in the upper front region.

Why Should a Mesiodens Not Be Left Untreated?

An untreated mesiodens — even one that is causing no immediate discomfort — carries a risk of progressive complications:

• Blocked or delayed eruption — The mesiodens physically obstructs the permanent incisors, preventing them from coming through in the correct position or at all
• Tooth displacement and rotation — The incisors are pushed off their normal eruption path, leading to misalignment that becomes harder to correct the longer it is left
• Root resorption — The roots of the adjacent permanent teeth can be gradually damaged by pressure from the mesiodens
• Diastema — A gap between the upper front teeth caused by the mesiodens forcing them apart
• Dentigerous cyst formation — A fluid-filled sac can develop around the crown of an unerupted mesiodens. Studies report cyst formation in approximately 4% to 11% of mesiodens cases. If left to enlarge, the cyst can cause significant bone loss and damage to adjacent tooth roots.
• Ectopic eruption — In rare cases, a mesiodens can follow an abnormal eruption path and emerge in the palate or, in very rare instances, into the nasal cavity

How Is a Mesiodens Diagnosed?

Clinical examination alone is not sufficient to diagnose a mesiodens. Radiographic imaging is essential.

Periapical and panoramic X-rays are typically the first step. A panoramic X-ray provides an overview of the entire dentition and is a reliable screening tool, though clarity in the midline region can be limited. A periapical or anterior occlusal X-ray gives a more focused view of the incisor region.

CBCT (cone-beam computed tomography) provides a three-dimensional image of the tooth's exact position, orientation, depth, and relationship to adjacent structures. It is recommended when surgical removal is being planned, particularly for deeply buried or inverted mesiodens where precise localization is critical to avoid damage to adjacent tooth roots during surgery.

This is one reason routine dental check-ups with periodic X-rays matter — a buried mesiodens will not announce itself. Early detection, before complications develop, gives the best outcome.

How Is a Mesiodens Treated in Children?

Surgical Removal

Extraction is the treatment of choice in most cases. At Drs. Nicolas & Asp Centers, children with mesiodens are assessed by our Specialist Pediatric Dentists. The surgical approach depends on where the mesiodens is sitting:

• Palatal approach — The most common approach. Used when the mesiodens is buried toward the roof of the mouth, accessed from the inside of the upper gum.
• Labial approach — Used when the mesiodens sits closer to the lip-facing surface of the jaw, accessed from the front of the gum.

For deeply buried or inverted cases, CBCT imaging is used to map the exact surgical route before the procedure begins. Sedation or general anesthesia may be used depending on the child's age, the complexity of the case, and clinical assessment.

Timing

Early removal is supported by evidence. Removing the mesiodens before significant root formation of the adjacent incisors is associated with fewer complications and a reduced need for orthodontic treatment. If the mesiodens is inverted, early removal is especially important — inverted teeth can migrate deeper into the jaw over time.

After Removal — Monitoring and Follow-Up

A clinical and radiographic review at six months confirms whether the previously blocked incisor is erupting on its own. Many blocked teeth erupt spontaneously after removal when there is adequate space and the procedure was done early.

If the incisor has not come through within six to twelve months, surgical exposure of the impacted tooth may be needed, followed by orthodontic guidance into position. Visit Exposure of Unerupted Teeth in Children for more information.

Orthodontic treatment may also be needed after removal to correct any displacement that has occurred.

How Is a Mesiodens Treated in Adults?

Adults are most commonly diagnosed with mesiodens either incidentally — on a routine dental X-ray — or when investigating unexplained crowding, a persistent gap between the front teeth, or discomfort in the upper anterior region.

Surgical Removal

Extraction remains the standard treatment. The surgical approach follows the same principles as in children — palatal or labial access depending on the position of the tooth, with CBCT imaging used for precise localization in complex cases. In adults, the procedure is typically performed under local anesthesia.

Why Timing Still Matters

Even in adults, early treatment following diagnosis is advisable. The longer a mesiodens remains in the jaw, the greater the risk of cyst enlargement, bone loss, and root resorption of adjacent teeth. A large dentigerous cyst, if left untreated, can cause damage that complicates or limits future restorative and prosthodontic options.

After Removal

Following extraction, the need for further treatment depends on what complications — if any — have developed. Options may include:

• Orthodontic treatment — to correct displacement or close a diastema that has formed
• Surgical exposure — if a permanent incisor has been blocked and requires guided eruption, though this is less predictable in adults than in children
• Restorative treatment — if adjacent teeth have been damaged and require restoration

Treatment planning in adults is individualized, taking into account the patient's age, the extent of any complications, and their clinical and aesthetic goals.