Relationships of human plasma fluoride and bone fluoride to age

There is evidence that fluoride levels in plasma correlate with the fluoride content in bones. The authors determined whether or not fluoride in plasma and bones might correlate with age. In 41 in-patients at the University Hospital, Iowa City, 36 of whom had been residing in fluoridated communities plasma fluoride was determined in the fasting stage by the fluoride ion selective electrode. The teeth of these children were compared with those of a neighboring city where the natural fluoride content in drinking water was 0.1 ppm. For the second sampling 42 months following the beginning of the program only 10 and 11 year old children - who had been 6 and 7 years old at the beginning of the experiment - were selected. Twenty-five boys and girls in each group were compared with a similar group of children as controls. After 28 months (approximately 33 rinsing with sodium fluoride solution) the DMF index in the fluoride-treated children was 18.4% less than in the controls. In the second group among 10 and 11 year old children after 42 months with 55 rinsings the difference was 35.0%. The author acknowledged that factors other than applications of sodium fluoride may have contributed tomore » the prevention of caries in the fluoride-treated groups.« less