Finding an unexpected tooth in the back of your mouth is a recognized dental phenomenon known medically as hyperdontia. This condition is characterized by having an excessive number of teeth beyond the standard count of 32 in the permanent dentition. The extra teeth are referred to as supernumerary teeth. These additional teeth require professional identification and management to determine if the structure is a true supernumerary tooth or a late-erupting third molar, commonly called a wisdom tooth.
Identifying the Extra Tooth (Classification and Terminology)
The classification of a supernumerary tooth depends on its location relative to your normal molars. An extra tooth situated directly behind the third molar is specifically termed a distomolar or distodens. These teeth essentially represent a fourth molar in the arch.
A different classification is the paramolar, which is a supernumerary tooth positioned adjacent to one of the molars. Paramolars typically emerge toward the cheek side (buccally) or the tongue side (lingually). These extra molars often appear smaller and more rudimentary in shape compared to a normal, functional molar. Distinguishing these from a normal third molar is important because a wisdom tooth is part of the standard dental formula.
Why Supernumerary Teeth Develop (Etiology)
The cause for the formation of supernumerary teeth is not fully understood, but the most accepted explanation involves the hyperactivity theory of the dental lamina. The dental lamina is epithelial tissue that forms the foundation for all tooth development. This theory suggests that localized, excessive activity or prolonged survival of these cells results in the formation of an extra tooth bud.
Other contributing factors include genetic predisposition, as supernumerary teeth often occur more frequently within the same family. While most cases are isolated, the presence of multiple extra teeth is sometimes associated with broader genetic disorders, such as Cleidocranial Dysostosis. The development of these extra structures is believed to be multifactorial, stemming from a combination of both genetic and environmental influences.
Health Complications Associated with Extra Teeth
The presence of an extra tooth can lead to several physical issues within the mouth. One of the most common problems is impaction, where the tooth fails to fully erupt due to obstruction from surrounding bone or adjacent teeth. The extra structure can cause misalignment or crowding of the normal teeth, and pressure can cause the roots of neighboring teeth to slowly resorb. A more serious complication involves the formation of a dentigerous cyst, a fluid-filled sac that develops around the crown of an impacted tooth, which can expand and cause significant bone destruction.
Professional Diagnosis and Treatment
Diagnosis
A dental professional must confirm the presence and exact location of the extra tooth to determine the course of action. Diagnosis typically begins with a thorough clinical examination, followed by specialized imaging. Panoramic X-rays are often used as an initial screening tool, providing a broad, two-dimensional view of the entire jaw structure.
Treatment Planning
For complex cases, especially those involving impaction near nerves or the sinus, a Cone Beam Computed Tomography (CBCT) scan may be used. This advanced imaging provides a three-dimensional view, allowing for precise localization of the extra tooth and assessment of its relationship to surrounding anatomical structures. Treatment is determined by the tooth’s position, its morphology, and whether it is causing complications.
Extraction and Monitoring
The most frequent treatment is surgical extraction, especially if the tooth is impacted, causing pain, or leading to cyst formation. The procedure often involves lifting the gum tissue and removing a small amount of bone to access the impacted tooth. For asymptomatic, non-erupted supernumerary teeth that are not causing any immediate problems, a dentist may recommend a watchful monitoring approach with regular radiographic check-ups. Surgical removal carries risks, including temporary or permanent nerve damage or potential damage to the roots of adjacent normal teeth.