Question

This is a biomaterial question can you please show how you get to the answer ?

3. Titanium alloy pedicle screws (Ti6A14V, ASTM F136) were evaluated for potential use in spinal fusions. The screws were either grit-blasted with hydroxyapatite/B-tricalcium phosphate particles to produce microscale roughness on the alloy surface (Ra 3.0 m) or roll-formed to produce smooth surfaces (Ra 0.1 μm). Pedicle screw fixation was evaluated by measuring the removal torque and angle stiffness. (a). Is there an advantage to grit-blasting with hydroxyapatite/B-tricalcium phosphate particles versus silica sand particles? Explain (b). The torsion torque versus torsion angle curve below is representative of which type of pedicle screw (ie., rough or smooth)? Explain. 3500 Z 2500 1500 5 10 15 20 25 30 Torsion Angle (degree) (c). Assuming a moment arm of 2.75 mm, using the torque versus angle curve shown determine the force (N) required to remove the pedicle screw and the angle stiffness (N-mm/degree).

Answer 1

in a metabolic transplant to the implent is controlled largely controlled by the nature and texture of plant of surface.compared to smooth smooth surface implant texture more surface area for integrating with bone.texture surface allow growth of tissues.