BIOLOGICAL REACTIONS TO BIOMATERIALS

Question 1

acute inflammation from what primary cells?

Answer 1

neutrophils

Question 2

chronic inflammation begins how many days after initial insult?

primary cells?

could form?

Answer 2

3-5 days

macrophages

body giant cells

Question 3

factors that affect fibrous capsule?

Answer 3

chemical properties of implant

• inert material
• corroding material
• additives or monomers leached from polymers

physical parameters

• movement
• sharp corners and edges

Question 4

metal sensitivity?

Answer 4

immune reaction that involves both humoral and cell meditated responses
-B/T cells

type IV hypersensitivity is primary from

response may be severe enough to necessitate removal of the device

Question 5

what metals induce sensitivity?

Answer 5

nickel

cobalt/chromium

Question 6

manifestations of metal sensitivity?

Answer 6

contact dermatitis

osteolysis

Question 7

bone mass is decreased over an extended period of time as a result of the presence of a rigid device?

Answer 7

stress shielding

Question 8

stress shielding is based on this principle?

Answer 8

wolff’s law, amount of bone present depends on the need for it

Question 9

consequences of stress shielding?

Answer 9

weakened bone susceptible to fracture upon removable of rigid device

Question 10

types of corrosion?

Answer 10

galvanic corrosion
crevice corrosion
fretting corrosion

Question 11

name this corrosion?

occurs when two dissimilar metals are placed in contact within a common electrolytic solution

Answer 11

galvanic corrosion

Question 12

name this corrosion?

localized corrosion that occurs in confined spaces

Answer 12

crevice corrosion’s

Question 13

name this corrosion?

occurs as a result of repeated relative micro motion between two surfaces

Answer 13

fretting corrosion

Question 14

what are the types of wear?

Answer 14

adhesive wear

abrasive wear

Question 15

occurs when two materials that are articulating against one another bond together and then dislodge as materials continue to slide past each other

what is this wear?

Answer 15

adhesive wear

Question 16

occurs when a hard material tears through a softer material

source of hard materials:
articulating surface
wear particle lodged between two articulating surfaces

Answer 16

abrasive wear

Question 17

reaction to wear debris is based on?

Answer 17

size of particles

Question 18

larger particles are encapsulated with?

Answer 18

fibrous tissue

Question 19

smaller particles are phagocytized by?

Answer 19

macrophages or foreign body giant cells

Question 20

metallic wear debris undergoes _____ in the phagocyte?

Answer 20

dissolution in acid

Question 21

minimal tissue response?

Answer 21

stainless steel and titanium particles

Question 22

more reactive response?

Answer 22

cobalt chromium alloy particles

Question 23

phagocytes do or do not possess enzymes that can degrade polymers so cells die?

Answer 23

do not

Question 24

these particle types cause an increase in number of phagocytic cells, so…

result is?

Answer 24

PMMA, polyethylene and silicone

bone resorption