At what age does tetracycline staining in permanent dentition typically occur?

Tetracycline staining in permanent dentition typically occurs during the critical period of tooth development when permanent teeth are forming, which is primarily in children aged 0-5 years. During this time, the developing dental tissues are most susceptible to the effects of tetracycline antibiotics. When these antibiotics are ingested during this vulnerable formation period, they can bind to the calcium ions in the teeth, leading to discoloration that presents as yellow, gray, or brown stains.

As for the other age ranges, while 5-10 years may involve some permanent teeth that have already erupted, it is less likely for tetracycline staining to occur after the critical developmental period has passed. Teeth that develop later in childhood are already less susceptible to the staining effects of tetracycline. Thus, 0-5 years is indeed the key age range when tetracycline use can lead to staining in the developing permanent dentition.