Physical properties of fluorosis bone.

The bones of two patients, one with a moderate and one with a severe chronic industrial fluorosis (stage I-II and stage III), and the bones of three control persons were examined. The following parameters were determined: the fracture load, the fracture load/unit area (resistance to pressure) of the body of the first lumbar vertebra, the bending strength of the neck of the femur and of the lower third of the femur, the fracture load/unit area and the modulus of elasticity of femoral slices 2 cm thick and of precisely defined cylinders from the femoral cortex. The microhardness according to Vickers on the cross section of the femur was also determined. The results obtained are discussed with regard to fluoride therapy of osteoporosis.