Abstract

The aim of this study was to investigate the effects of different fluoride concentrations in drinking water on mechanical strength of femoral bone in young growing rats. Forty 6-week-old female Wistar rats were randomised into four groups. One group served as a control group receiving distilled water, and the other three groups received water containing NaF at levels of 8, 30, and 60 mg F/L. After six weeks, all rats were sacrificed and the femoral bones from each rat were assayed for bending strength of the femoral shaft and failure load of the femoral neck. The femoral neck of rats drinking water containing 8 mg F/L showed the highest failure load, decreasing significantly in rats drinking 30 and 60 mg F/L. Bending strength of the femoral shaft decreased significantly after fluoride therapy. We conclude that high fluoride intake decreases bone quality of the femoral shaft and neck in young growing rats. On the other hand, sodium fluoride administered in lower concentration increases the strength of the femoral neck.