Children grow up to 20 baby teeth, while adults are expected to have 32 permanent teeth. But, there are people born with more than 32 teeth.
A condition called hyperdontia affects more than 200,000 Americans per year. It is a condition wherein an individual have supernumerary teeth or more teeth than regular that can appear in any area of the dental arch and can affect any dental organ. In a survey of 2,000 school children, supernumerary teeth were found to have 0.8 percent prevalence on primary dentitions and 2.1 percent on permanent dentitions.
According to the Canadian Dental Association (CDA), the cause of supernumerary teeth remains to be incompletely understood. But, one theory suggests that supernumerary teeth may be a result of the dichotomy of the tooth bud. Another theory proposes the hyperactivity theory which states that supernumerary teeth are formed because of local, independent, conditioned hyperactivity of the dental lamina. Heredity may also be a factor in the occurrence of these teeth.
Supernumerary teeth may be detected through a chance finding on a radiograph or as the cause of an impacted central incisor. The spontaneous eruption can also lead to its discovery.
Supernumerary teeth can be classified into different categories, depending on the shape and position of the teeth. When classified by shape, they have four categories namely the supplemental, tuberculate, conical, and odontoma.
- The supplemental supernumerary has a normal shape and is the duplication of teeth in the normal series. This type is usually found at the end of the tooth series.
- Tuberculate is barrel-shaped and possess more than one cusp or tubercle. Often paired, tuberculate supernumeraries are commonly located on the palatal aspect of the central incisors. According to CDA, this type rarely erupts and are often associated with the delayed eruption of incisors.
- Conical is peg-shaped and commonly found in the permanent dentition. This type of supernumerary may occasionally be found high and inverted into the palate.
- On the one hand, the fourth category of a supernumerary tooth, odontoma, refers to any tumor of odontogenic origin. However, this category is not universally accepted. Odontoma is further sub-divided into two categories – complex composite odontoma and compound composite odontoma.
Hyperdontia is more common with permanent teeth than baby teeth, affecting more individuals from ages 14 to over 60 than those below 13 years old. It is considered chronic, persisting for a long time or lifelong.
It is usually self-diagnosable, does have symptoms, and is treatable by a medical professional. However, those with hyperdontia may experience crowding, failure of eruption, displacement, pathology, alveolar bone grafting, implant site preparation, and asymptomatic.
The treatment for hyperdontia is dependent on the type and position of the supernumerary tooth and how it affects the adjacent teeth. It is best to consult your dentist for the right treatment plan.
The supernumerary tooth may require removal especially when:
- Delayed eruption of central incisor
- Evident altered eruption or displacement of central incisors
- Associated pathology
- Proximity with an active orthodontic alignment of an incisor
- Compromise the secondary alveolar bone grafting in cleft lip and palate patients
- Tooth is on the designated bone for implant placement
- Spontaneous eruption of supernumerary has occurred