Tetracycline was introduced in the middle of the twentieth century and was used widely for the relief of nausea associated with morning sickness. In 1963, the Food and Drug Administration (FDA) issued a warning against the use of tetracycline as an antibiot- ic for young children and pregnant women due to irreversible dental staining. Tetracycline affects the teeth during the formation period, ranging from the embryo in the second trimester of pregnancy to the eighth year of the child’s tetracycline molecule affects the dentin by carrying the hydroxyapatite crystal that causes a yellowish-gray color (Figure 7-1).The severity of the tetracy- cline stains may .
