A new study, "Prevalence and Severity of Dental Fluorosis in the United States, 1999-2004," has estimated that dental fluorosis now affects 41 percent of adolescents aged 12-15 in the U.S. Fluorosis is mottling of dental enamel. It is characterized by a white chalky appearance to the enamel, whichgradually undergoes black and brown discoloration, as well as cracking and pitting of the teeth. Fluorosis is caused by a child receiving too muchfluoride during tooth development. Dentists will tell their patients that fluorosis is just a cosmetic problem. It is not. Fluorosis is the external manifestation of toxic fluoride poisoning. The bones are also being affected. This is called skeletal fluorosis, and it often results in a misdiagnosis of osteoporosis. Fluoride does not prevent tooth decay. It is a dangerous toxin that must be avoided. Do not drink fluoridated water, and do not use toothpaste that contains fluoride.