The Effect Of Fluoride On Osteogenesis Invitro

Abstract

In order to study the effects of fluoride on bone formation, a model system in which de novo osteodifferentiation and bone formation occurs was utilized; the chick periosteal osteogenesis (CPO) model. Various biochemical methods including measurement of alkaline phosphatase activity (bone cell phenotype marker), H-3-thymidine incorporation (cellular proliferation), protein content (culture size), calcium and phosphorus uptake (mineralization) were used to analyze the effects of fluoride on osteogenesis. In addition, the use of electron microscopy, electron diffraction and x-ray analysis facilitated localization and measurement of early mineral deposits. The data indicated that fluoride treatment induced an increase in alkaline phosphatase activity of bone cells as well as increased cellular proliferation. Mineral accumulation as assessed biochemically was apparently decreased or slowed. Ultrastructural studies using both conventional fixation and cryo-fixation methods suggested that the bone-mineral produced in the presence of fluoride was less soluble whereas crystal size remained constant. These studies indicate that fluoride may stimulate osteogenic cell activity directly but could retard mineralization. However, the mineral produced is less susceptible to dissolution and possibly resorption.