Iden N. Hill

The Evanston dental caries study. XV. The caries experience rates of two groups of Evanston children after exposure to fluoridated water.

THIS paper reports the findings of the 1953 and 1954 dental examinations made on the 6to 8and 12to 14-year-old continuous resident Evanston children. Comparisons are made of the data for the 1953 and 1954 groups to those of children of the same age examined in the study in 1946. The 1953 group was exposed to fluoridated water from 71 to 82 months and the 1954 group 83 to 94 months at the time of dental examinations.

The Evanston Dental Caries Study. XI. The caries experience rates of 12-, 13-, and 14-year-old children after exposure to fluoridated water for fifty-nine to seventy months.

THE dental caries experience rates of Evanston school children, aged 12, 13, and 14 years, indicated a reduction of 12.19 per cent after these children had been exposed to artificially fluoridated water for a period of twentythree to thirty-four months.1 This report on the dental caries experience rates is for children of the same age, presumably influenced by the same conditions, but with exposure time to fluoridated water increased from twenty-three to thirty-four months to fifty-nine to seventy months at the time of dental examination.

Significance of Permanent Teeth Extracted for Orthodontic Reasons

This report deals with the extraction of permanent teeth because of crowding or malposition or in connection with orthodontic treatment. The analysis of the data is considered from a biostatistical point of view and is based on the records of 16,138 examinations.