Acrylics 1

Question 1

Acrylic uses

Answer 1

Orthopedic applications

Fracture augmentation

Question 2

Orthopedic apps.

Answer 2

Cement spacers
Antibiotic therapy
High dose concentration

Question 3

Acrylic examples

Answer 3

PMMA

Question 4

PMMA bone cements

Answer 4

Free-radical
Exothermal reaction
Shrinkage
Varying viscosity

Question 5

Residual monomer issues

Answer 5

Due to incomplet Polymerization
acts as plasticizer negatively affecting mechanical performance
Leaching

Question 6

Dental acrylics

Answer 6

Composite, temp bridges and crowns, fillings

Question 7

Dental considerations

Answer 7

Significant shrinkage can occur
Photo or chem. cured
Rapid and efficient is crucial

Question 8

OHMWPE

Answer 8

Low friction load bearing
Low wear rates
High yield will min. deformation and creep resistance

Question 9

OHMWPE Considerations

Answer 9

Wear particles - can produce billions annually

X-linking improves wear resistance in load bearing apps.

Question 10

X-linking

Answer 10

Improves wear resistance

(-) formation of free radicals leads to oxidation

Question 11

Oxidation

Answer 11

Caused by free radicals and sterilization
(-) shelf life
(-) + elastic modulus
(-) - fatigue crack resistance

Question 12

UHMWPE Problem Fixes

Answer 12

Re-melting eliminates free-radical but (-) alters crystallinity
Annealing preserves crystallinity but (-) ineffectively reduces free radicals

Question 13

Vit-E

Answer 13

UHMWPE additive that will quench free radicals and improve properties
(-) inconsistant blending