During which stage of tooth development can anomalies of tooth number occur?

Tooth development occurs in several stages, each critical to the formation of dental structures, and anomalies in tooth number primarily arise during the initiation stage. This stage is crucial because it is when the dental lamina is formed and the initial decisions regarding the number and location of teeth occur.

During the initiation stage, defects can lead to conditions such as hypodontia (missing teeth) or hyperdontia (extra teeth). Since this stage determines the number of tooth buds that develop, any disruption—whether due to genetic factors, environmental influences, or developmental disturbances—can result in anomalies related to tooth number.

In contrast, the other stages (apposition, histodifferentiation, and maturation) involve further development of teeth that have already been initiated and are focused more on the structure and mineralization of the teeth rather than the number of teeth forming. Thus, anomalies of tooth number specifically originate in the initiation phase of tooth development.