Developmental defects of enamel: a study of 12-year-olds in Hong Kong.

The prevalence of enamel defects in Hong Kong was determined using a randomly selected group of 12-year-olds (N = 1,069). The most common defects were enamel opacities, which occurred in 99.6% of the Chinese children, with 63.4% of them having more than 20 teeth affected. Almost 17% of the Chinese children had disfiguring enamel discoloration, but only one of the non-Chinese children had this defect. The high prevalence of enamel defects may be related to the high frequency of use of tetracycline, metabolic disturbances, and a greater-than-optimal intake of dietary fluoride.