Supernumerary teeth. Causes. Approach in the dental office
The supernumerary teeth – a disorder also known as hyperdontia, is a common number abnormality, especially in the permanent dentition. It can affect any tooth, but is most commonly found in the upper jaw, frontal region.
The prevalence of this anomaly is 1-4%, most of the time only one tooth is supernumerary.
Physiological dentition
Normally in the oral cavity we have 20 temporary teeth and after their replacement, 32 permanent teeth. In the case of the temporary ones, the eruption becomes definitive around the age of 12. For permanent ones, by the age of 21 we should have a complete eruption.
A person who develops a higher number of teeth suffers from hyperdontia.
The causes of an overgrown tooth are related to genetic factors or defects in the embryogenesis of the teeth buds.
Forms of hypodontia
Supernumerary teeth can occur in several forms:
Extra tooth: has the same structure and morphology as the neighboring tooth, fitting harmoniously into the dental arch.
Tuberculated tooth: has a small, dwarf shape, being in disharmony with the neighboring teeth.
Tapered tooth: has the shape of an undersized, conical canine. It may have the appearance of a polished tooth.
Complex odontome: disorganized, amorphous mass of tooth substance that does not follow the sequence of layers.
The most common form is that of a tooth still between the two upper central incisors, called mesiodens. This anomaly frequently raises aesthetic issues.
Implications for oral health
A supernumerary tooth may erupt through the dental arch or remain embedded in the bone.
If teeth have erupted on the arch, we face the following situations:
Aesthetics: supernumerary teeth can spoil the harmony of the dental arches by their mere existence or can alter the position of their neighbors. Thus, we can encounter rotations, malposition, ectopias.
Chewing: food intake and the chewing act will be deficient.
Hygienisation: food may be retained in the spaces created by the supernumerary teeth, forming an environment conducive to the development of bacterial plaque.
Orthodontics: dental alignment will suffer; atypical movements will be generated which will induce stress and wear on the temporomandibular joint.
Gingival trauma: lack of contact points between neighboring teeth will allow hard aliments to impact the gums, causing inflammation.
Supernumerary teeth that have not erupted can be detected clinically, by the fact that they are blossoming beneath the surface they are on, or radiologically. They are commonly found in the palate, nasal fossae, maxillary sinus or jawbone and can cause embarrassment, pain or even infection.
Therapeutic approach
In therapeutic management, we have two options:
Keeping the teeth on the arch
Extraction of supernumerary teeth
Whichever solution is chosen, the ultimate goal is to overcome the disturbances induced by hyperdontia.
If the supernumerary tooth is retained, it is harmonized with the arch through dental, orthodontic or prosthetic interventions.
Extraction of the supernumerary teeth is indicated if it is a hindrance to the functionality of the dental arches.
The dentist, during the consultation, will examine and identify any existing anomalies. The clinical examination must be complemented by a radiological examination in order to make a correct diagnosis and indicate the appropriate therapy to the patient.
