[Effect of sodium fluoride on ectopic induction of bone tissue]

Fluoride is a very potent bone stimulating factor. The aim of the study was to assess the influence of sodium fluoride on bone formation and resorption in the process of experimental ectopic bone formation. Ectopic bone formation was induced 10 days after the start of treatment. Two groups of 15 rats each, study and control, were formed. The study group received 100 ppm sodium fluoride in water. Devitalised bone matrix grafts were implanted intramuscularly in two thorax regions. Eight weeks later the ossicles were removed and prepared without decalcification for histomorphometric analysis. Osteoid perimeter (O.Pm) and osteoblast number (N.Ob) were higher in the study as compared to the control group (42.24 +/- 4.14 vs. 12.18 +/- 2.89; p < 0.01 and 26.07 +/- 3.26 vs. 10.24 +/- 1.39; p < 0.01, respectively). Osteoclast number (N.Oc) was increased in the study group (4.31 +/- 0.40 vs. 2.53 +/- 0.31; p < 0.01). No significant differences in bone area (B.Ar/T.Ar) were found (19.36 +/- 2.26 vs. 18.67 +/- 3.71). It was concluded that sodium fluoride not only increases osteoblast activity but also stimulates bone resorption in bone matrix grafts.