Supernumerary teeth, also known as hyperdontia, is a condition characterized by the development of more teeth than the usual number. A typical adult mouth contains 32 permanent teeth, and these extra teeth can occur in both children’s primary teeth and adult’s permanent dentition. They may erupt into the mouth or remain impacted within the jawbone. Their appearance is more frequent in permanent teeth, with a prevalence of 1.5-3.5%.
Causes of Supernumerary Teeth
The precise origins of supernumerary teeth are not entirely understood, but evidence points to a combination of genetic and environmental influences, as the condition can run in families. One theory proposes that hyperactivity of the dental lamina, the tissue that initiates tooth formation, leads to the development of extra tooth buds. This overactivity results in teeth beyond the standard count.
While many cases of hyperdontia are an isolated anomaly, the condition is also associated with several genetic syndromes. People with conditions like cleft lip and palate, Gardner’s syndrome, or cleidocranial dysplasia have a higher likelihood of developing them. The presence of these extra teeth can be an early indicator that prompts investigation for an underlying systemic condition.
Common Types and Locations
Supernumerary teeth are classified by their shape (morphology) and position within the dental arch. Their shape can vary significantly, from resembling a normal tooth to being rudimentary. A supplemental tooth mimics the anatomy of an adjacent normal tooth. In contrast, some are conical or peg-shaped, while others, called tuberculate, are more barrel-shaped and rarely erupt. An odontoma is a disorganized mass of dental tissue that looks more like a tumor than a tooth.
The location of these teeth is also a key identifier. The most common type is the mesiodens, a small, conical tooth that develops between the two upper central incisors. Paramolars are extra teeth found next to the molars, either on the cheek or tongue side. Another type, the distomolar, is located behind the last molars, including the wisdom teeth.
Potential Dental Complications
The presence of supernumerary teeth can lead to a variety of dental problems, though some may cause no issues. A frequent complication is the failure of permanent teeth to erupt properly, as the extra tooth can physically block their path. This can lead to impaction, where a normal tooth becomes trapped in the jawbone.
Overcrowding is another issue, as the extra teeth take up space and can cause displacement or rotation of adjacent teeth, leading to misalignment (malocclusion). The irregular positioning of teeth can also make effective brushing and flossing difficult, increasing the risk of cavities and gum inflammation. In some instances, a fluid-filled sac called a dentigerous cyst can form around an unerupted supernumerary tooth.
Management and Treatment Options
The management of supernumerary teeth depends on their type, location, and the problems they are causing. If the extra tooth is asymptomatic and not interfering with other teeth, a dentist may recommend observation. This involves monitoring the tooth with regular clinical exams and radiographs to ensure no complications arise.
When a supernumerary tooth causes problems like pain, crowding, or prevents the eruption of other teeth, extraction is the most common treatment. If the extra tooth has caused misalignment, orthodontic treatment like braces may be necessary after the extraction to correct the bite. Early detection through routine dental check-ups is beneficial for preventing more complex issues.