Self-test - Orthopaedic Biomaterials in Research and Practice - page 418

Question 7 refers to Figure 17.3

7. From Figure 17.3, select the letter or letters that best answer the
queries:

Strongest material is? ____

Stiffest material is? ____

Most ductile material is? ____

Material most likely to be a ceramic? ____

Material most likely to be a polymer? ____

(10)

8. A 2.1-mm-diameter Steinmann pin, when compared with a
1.4-mm-diameter pin, both made of the same material, is (select
the best answer[s])

A. 50% stiffer in bending ______

B. 50% stronger in tension ______

C. 125% stronger in tension ______

D. 250% stiffer in bending ______

E. 400% stiffer in bending ______

(15)

9. Rank the following materials from 1 (lowest) to 5 (highest) for
indicated properties:

Elastic modulus Ductility Strength

UHMWPE ______ ______ ______

Cortical bone ______ ______ ______

Cancellous bone ______ ______ ______

Co-base alloy ______ ______ ______

Ti-base alloy ______ ______ ______

(15)

10. The following are known to affect the efficacy of electric stimula-
tion of bone fracture repair ( true or false ):

Electrode positioning ____

Current density ____

Fracture gap size ____

Electric field ____

Implant porosity ____

(5)