How many teeth have you had filled in the past two years If you follow the advice of Dr. Faustick, you may be able to reduce tire number of your visits to a dentist. Dr. Faustick conducted a two-year survey to find out how to prevent or reduce dental decay. 946 students took part in an experiment. 523 students cleaned their teeth within ten minutes of eating: when possibly they used a toothbrush, when this was impossible they washed their mouth thoroughly with water. The remaining 423 students merely cleaned their teeth when they went to bed and when they got up in the morning. All the students had their teeth X-rayed at the end of the first and second years. At the end of the first year, the night and morning group had. three times as many decayed teeth as the former group. Dr. Faustick has cleaned his teeth after each meal for thirteen years and has not had a single decayed tooth. He pointed out that sugar is a major agent in dental decay. Particularly the sugar in sweets, cake
A. 13.
B. None.
C. 1.
D. A few.
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