| Abstract: | Histomorphometric study was made on a seriesof sections of undecalcified epiphyseal femoral specimens from rats with experimental fluorosis. Theresults revealed osteosclerosis in Group A (5 ppm)being more severe than that in Group B (25 ppm)With the increase of fluoride dose, the parametersfell down instead of increased in parallel. There isseemingly a threshold over which osteosclerosis influorosis becomes less severe. In contrast to Bely'sconclusion the authors proposed that, fluoride toxi-city, besides decreasing the number of osteoblasts,may also activate the osteoblasts. The number ofosteoblasts may be increased with relative lowerdose of fluoride also. The net outcome is the increment in bone volume. When toxic dose offluoride is higher enough (higher than the proposedthreshold), however, the number of osteoblasts andits activity are inhibited. So are the osteocytes. Thisinterpretation may be the cytological basis forosteosclerosis in the experimental fluorosis. |
