Primary (deciduous) Dentition (20 teeth)
= 5 teeth in each quadrant: NO premolars + only 2 molars
Permanent Dentition (32 teeth)
= 8 teeth in each quadrant
Development:
- from occlusal surface toward root apex within maxilla and mandible; resorption of root of primary tooth during migration toward oral cavity; eruption continues until tooth occludes with tooth from opposite jaw
Hypodontia = <32 teeth
Hyperdontia = >32 teeth
- Frequency: molar (44%), premolar (33%), incisor (23%)
- May be associated with: Gardner syndrome, cleidocranial dysplasia
- mesiodens: in maxillary midline adjacent to incisors
- distodens: posterior to 3rd molar, often impacted causing dental inflammation / infection
Cx of supernumerary teeth:
- crowding / abnormal eruption / noneruption / damage of normal teeth
DDx: odontoma, hamartoma of odontogenic origin
