The effects of fluoride ions (F/sup -/) on the mechanical properties of bovine bone tissue with different ultrastructures

Bovine cortical bone samples were tested in tension after being treated for three days in a 2.0M NaP solution. Randomly selected bone samples were obtained from 18 month old steer, 24 month old cow and 96 month old cow. The elastic modulus (E) and ultimate tensile stress (UTS) were obtained for a control group (0.145M saline) and a fluoride group for each age of bovine. The fluoride ion (F/sup -/) content of the bone was also measured to approximate the amount of absorption of the test conditions (0.952%). The results showed that fluoride ions induced a more pronounced effect on younger bone causing a greater overall decrease in E and UTS. The decrease in mechanical properties occurs because fluoride is thought to influence the interphasic bonding between the carbonated hydroxyapatite mineral and organic phases present in bone along with the bone mineral structure.