Scanning Electron Microscopy of Periosteal Bone Formation in Fluoride Treated Rats
Anorganic preparations of the femoral diaphyses of young rats given 150 ppm fluoride in the drinking water for 10 weeks are examined by scanning electron microscopy and compared to similar preparations from untreated rats. In femoral bone of untreated animals, periosteal apposition areas show incompletely mineralized collagen fibers. Ordered mineral deposits are uniform in size, closely packed, and globiform in shape. Osteocyte lacunae are shallow, regular in outline, and lined by smooth-surfaced walls. In fluoride-treated animals apposition areas appear frayed, consisting of bunches of poorly defined needles; mineralized segments vary in size with wide spaces in between. The uneven surface texture reflects an irregular orientation of the collagen fiber bundles, There is an increase in osteocyte lacunae which are buried at various depths on the periosteal surface. The lacunar walls are irregular with mineralized segments running in all directions. Our observations indicate that the ingestion of fluoride for 10 weeks in the rat results in an increase in periosteal matrix and bone formation presumably as a result of increased osteoblastic activity. In addition, there is an inhibition of the process of mineralization at the periosteum due to a delay in the initiation of mineralization in osteoid and young bone. Further, the irregular orientation of collagen fibers and numerous incompletely buried osteocyte lacunae are features of immature, woven bone.
Ream, L. J.,
Pendergrass, P. B.,
& Scott, J. N.
(1981). Scanning Electron Microscopy of Periosteal Bone Formation in Fluoride Treated Rats. The Ohio Journal of Science, 81 (Annual Meeting), 115.