Intro to Biomaterials

Question 1

Nonviable material used in a medical device, intended to interact with biological systems; defined by their application not chemical make-up

Answer 1

biomaterials

Question 2

Physical requirements of biomaterials

Answer 2

hard and flexible materials

Question 3

Chemical requirements of biomaterials

Answer 3

• must not react with any tissue in the body
• must be non-toxic to the body
• long-term replacement must not be biodegradable

Question 4

What do biomaterials have in common?

Answer 4

-must have intimate contact with patient’s tissue or body fluid providing a real physical interface

Question 5

biomaterial introduced in dentistry in 1937

Answer 5

PMMA - polymethyl methacrylate

Question 6

biomaterial first used to fabricate an arterial prosthetic in 1958

Answer 6

PETE, a.k.a. Dacron Fabrics - polyethylene terephthalate

Question 7

In 1960, Charnley uses _______ and _________ for total hip replacement

Answer 7

PMMA and stainless steel

Question 8

What year was Society of Biomaterials was formed?

Answer 8

1975

Question 9

High molecular weight molecule made up of a small repeat unit

Answer 9

polymer

Question 10

low molecular weight compound that can be connected together to give a polymer

Answer 10

monomer

Question 11

short polymer chain

Answer 11

oligomer

Question 12

polymer made p of 2 or more monomers

Answer 12

copolymer

Question 13

3 types of copolymer?

Answer 13

random, alternating and block

Question 14

What does it mean to have good compatiblity?

Answer 14

Good biocompatibility is achieved when the material exists within a living body without adversely or significantly affecting it or being affected by it.

• material should have adequate mechanical strength, chemical and physical properties
• biomaterials must be compatible with body tissues mechanically, chemically as well pharmacology

Question 15

Explain the 3 generations of biomaterial

Answer 15

• 1st gen: specified by physicians; accidental rather than by design
• 2nd gen: developed through collabs of physicians and engineers; engineered implants and build on 1st gen exp.
• 3rd gen: bioengineered implants using bioeng. materials

Question 16

Biomaterial of heart valve

Answer 16

• Fabricated from carbons, metals, elastomers, fabrics and natural valves (pig) and should NOT react w/ chem in body
• attached by polyester mesh
• tissue growth facilitated by polar oxygen-containing groups
• pretreated to reduce immunologic reactivity and enhance durability

Question 17

Which heart valve is used most widely?

Answer 17

bi-leaflet tilting disk heart valve

Question 18

Problem with substitute heart valves

Answer 18

degeneration of tissue, mechanical failure, postop infection and induction of blood clot

Question 19

small titanium fixture that serves as the replacement for the root portion of a missing natural tooth and are capable of osseointegration

Answer 19

dental implant

Question 20

What material are most dental implants made of?

Answer 20

pure Ti screw-shaped cylinders that act as roots for browns and bridges, or as supports for dentures

Question 21

phenomenon where a material is capable of bonding to bone

Answer 21

osseointegration

Question 22

What is the special requirement in the application of dental implants?

Answer 22

it should have the ability to form a tight seal against bacterial invasion where the implant traverses the gingival (gum)

Question 23

biomaterial of hip joint replacement

Answer 23

Fabricated from specific high-strength metal alloy (corrosion resistant), composites, ultrahigh molecular weight polyethylene and thermoset plastics

Question 24

biomaterial of intraocular lenses

Answer 24

made of polymer modified masterseal (PMM), silicone elastomer, and other materials used to replaced a natural lens when it becomes cloudy

Question 25

characteristics of vascular grafts

Answer 25

- must be flexible - designed w/ open porous structure - achieve and maintain homeostasis - porous - permeable - good structure retention - adequate burst strength - high fatigue resistance - low thrombogenecity - good handling properties - biostable

Question 26

vascular grafts permeability

Answer 26

- braids: 350-2500 ml cm2/min - loosely woven knits: 1200-2000 ml cm2/min - tightly woven knits: 2000-5000 ml cm2/min weaves: <800 ml cm2/min

Question 27

characteristics biomaterials science

Answer 27

- multidisciplinary - many diverse materials - dev't. of biomaterials devices - magnitude of the field - success and failure

Question 28

hard tissue replacement materials

Answer 28

metals, ceramics, used in orthopedic and dental materials

Question 29

soft tissue replacement materials

Answer 29

polymers, cardiovascular and general plastic surgery materials

Question 30

central issues for biomaterials

Answer 30

1) what represents a good design 2) who should be responsible when devices perform "with an inappropriate host response" 3) what are the cost/risk or cost/benefit ratios for the implant or therapy

Question 31

subjects integral to biomaterials science

Answer 31

- toxicology - biocompatibility - functional tissue structure and pathobiology - healing - dependence on specific anatomical site - mechanical and performance requirements - industrial involvemen - ethics - regulaion

Question 32

deals with substances that migrate out of biomaterials

Answer 32

toxicology

Question 33

critical considerations to workers in the functional tissue structure and pathobiology field

Answer 33

1. the key principles governing the structure of normal and abnormal cells, tissues and organs 2. the techn. by w/c the structure and function of normal and abnormal tissue are studied 3. the fundamental mechanisms of disease processes

Question 34

mechanical and performance requirements

Answer 34

mechanical performance, mechanical durability and physical properties (functional)