Effects of Dietary Fluoride and Age of Fluoride Concentration in Hard Tissue in Rats

• Published in: JOURNAL OF DENTAL HEALTH Vol. 36; no. 1; pp. 36 - 46
• Main Authors: NAKAMINAMI, Kazumi, NIWA, Motoo
• Format: Journal Article
• Language: English
• Published: Japanese Society for Oral Health 1986
• Subjects: Aging; Fluoride; Rat hard tissues
• ISSN: 0023-2831; 2189-7379
• DOI: 10.5834/jdh.36.36

The relationship between aging and fluoride administration was studied in Donryu rats. In a preliminary study, rats were continuously fed with an 18% casein food until spontaneous death, and the aging process was divided into the following 3 stages: 4, 15 and 60 weeks of age. In the actual study, rats were fed with the 18% casein food and fluoride was added to the food for a period of 4 weeks starting at 4, 15, or 60 weeks of age. Animals were killed after completion of the 4-week fluoride administration. The incisors, molars and femur were excised in order to determine fluoride levels in these hard tissues. 1. The inhibition of body weight gain was greater in older rats and in those which received greater doses of fluoride. In particular, body weight loss was noted in those which received fluoride starting at 15 or 60 weeks of age. 2. Food consumption decreased as fluoride concentration in food increased in older animals. 3. As fluoride doses increased, fluoride levels increased in dentin of incisors and molars and in femurs. 4. Fluoride levels in hard tissues tended to decrease with aging but only slightly in the dentin of incisors. 5. The effect of aging was significant in molar dentin in which fluoride levels decreased significantly in 15-week or 60-week old rats as compared to 4-week old rats.