Ceramics and composites - Orthopaedic Biomaterials in Research and Practice - page 220

The elastic moduli of most casting materials are not well known.
However, modulus is not an important parameter since cast stiffness is
increased by the surgeon or cast technician adding extra layers of mate-
rial and the final cast is “decoupled” from the patient's limb by a highly
compliant layer of padding.
additional problems
PROBLEM 8.3
Compared with metals, nonresorbable ceramics are (select the best
answer[s])
A. More ductile
B. Tougher
C. Stiffer
D. More brittle
E. Less chemically reactive
ANSWER:
C , D , and E.
PROBLEM 8.4
Bioactive ceramics are (select the best answer[s])
A. Resorbable
B. Ductile
C. Osteoinductive
D. Osteoconductive
E. Able to form bonds to tissue
ANSWER:
E . This is one of the properties of some bioactive materials. They are not
ductile; their other properties depend on composition and structure.
PROBLEM 8.5
Polymer matrix composites (true or false)
1. Are always anisotropic
2. Are less stiff than pure alumina ceramics
3. Are fatigue resistant
4. May be made from any polymer-fiber combination
5. May be made with a wide range of stiffnesses