Hyperdontia

Hyperdontia, also known as supernumerary teeth, is a dental condition characterized by the presence of more teeth than the normal number for an individual’s dentition. It can affect primary or permanent teeth, though it is more common in the permanent dentition. The most frequent supernumerary tooth is a mesiodens, located between the maxillary central incisors. Other forms include distomolars (behind the third molars) and paramolars (near existing molars). Supernumeraries can be conical, tuberculate, or supplemental in shape.

The etiology of hyperdontia is multifactorial and not fully understood. Genetic factors play a role, with familial patterns observed in some cases. It can also occur as part of certain syndromes, such as cleidocranial dysplasia and Gardner syndrome. Environmental factors may contribute but are less clearly defined. The condition shows variable expression and penetrance.

Clinically, many cases are asymptomatic and discovered on routine radiographs. Supernumeraries can cause crowding, diastema, delayed eruption, or displacement of adjacent teeth, and in some instances may form odontogenic cysts or contribute to impaction. Diagnosis relies on dental imaging, including panoramic radiographs; when precise localization is needed, cone-beam computed tomography may be used.

Management depends on the tooth’s position, potential to erupt, and impact on adjacent teeth. Asymptomatic supernumeraries that do not interfere with eruption or alignment may be monitored. Surgical extraction is common when they cause crowding, delay eruption, or threaten eruption of adjacent teeth. The timing of removal is individualized and often coordinated with orthodontic treatment.

Epidemiologically, hyperdontia affects approximately 1–3% of the population in permanent dentition, with mesiodens being the most frequent type. It is somewhat more common in males and more often involves the maxilla.