When does permanent dentition usually show tetracycline staining?

Tetracycline staining of permanent dentition is typically associated with exposure to tetracycline antibiotics during critical periods of dental development, particularly when the teeth are forming. This exposure can lead to intrinsic staining, which appears as a characteristic yellow to brown discoloration.

The correct choice indicates that this staining usually occurs between 0 and 5 years old because it is during this time that the primary teeth are being formed, and any exposure to tetracycline can lead to staining of the developing permanent teeth. The timing is crucial, as teeth begin to mineralize early in life, and tetracycline can bind to calcium in the developing enamel and dentin.

Other options suggest different age ranges that are not typically associated with permanent dentition development. For example, exposure during fetal development may affect primary teeth, but the staining of permanent teeth particularly is more prominent if the drug exposure occurs while the permanent dentition is developing, which usually aligns with early childhood. The timeframe during puberty is also not relevant for the development of permanent teeth, which would have completed their formation and mineralization by that stage.