Number of teeth
- Hypodontia or partial anodontia refers to less than 6 teeth missed in both jaws. The most common teeth to be absent are third molars, upper second incisor and second premolars. Down’s syndrome may be related to Hypodontia.
- Oligodontia refers to more than 6 teeth missed in both jaws.
- Anodontia (total anodontia), which is the total loss of teeth, is extremely rare. It is has been reported in patients suffering from ectodermal dysplasia.
- Hyperdontia one or more teeth in addition to the normal dentition. If the extra tooth is small and rudimentary in shape is called supernumerary. While supplemental tooth is referred to an extra tooth near copy in shape and size of a normal tooth. A mesiodense is a supernumerary at or near the midline of maxilla. Hyperdontia can be associated with specific syndromes such as cleidocranial dysplasia and gardener’s syndrome.