Biomaterials Test 1

Front 1

clinical significance of biomaterials

Back 1

1. MP (material properties) determine required manipulation(wrong manipulation--premature failure.

2. MP affect performance(wrong materials--premature failure.

3. ease of procedure, convenience of use, cost effectiveness, and efficiency of resources enhance dental practice.

4.In restorative dentistry, MP affect dental design, design of restoration or prothesis depends on material properties.

5.improve bottom line by becoming informed consumer.

6. must pass written board exam to get license

Front 2

regulation of biomaterials

Back 2

1. selection of safe and effective materials is responsibility of clinician.

2.organizations govern material quality(ASTM, ASM, etc).

3. organizations govern dental materials(FDA,ADA, ISO).

Front 3

classification of materials

Back 3

metals, ceramics, polymers

composites, semiconductors

Front 4

metals

Back 4

larges number of non-localized electrons, many properties are directly attributed to these electrons, extremely good conduction of electricity and heat, not transparent to visible light, polished metal surface has lustrous appearance, metals are strong yet deformable

Front 5

ceramics

Back 5

most frequently oxides, nitrides, and carbides, can be composed of clay minerals, cement, or glass, typically good insulators to the passage of heat and electricity, more resistant to high temp and harsh environment than metals and polymers, hard but brittle

Front 6

polymers

Back 6

plastic and rubber materials, organic compounds chemically based on carbon, hydrogen, and other nonmetallic elements, large molecular structure, low densities and may be extremely flexible

Front 7

composites

Back 7

consist of more than one type of material, designed to display a combination of the best characteristics of each of the component materials, many recent material developments have involved composite materials, common example in dentistry are composite resin restorative materials.

fiber glass is common model type from composites, glass fibers in a polymer matrix--strength comes from glass component and flexibility comes from polymer

Front 8

primary bonding

Back 8

covalent bonds, ionic bonds, metallic bonds

Front 9

covalent bonds

Back 9

atoms share their electrons so that each electron shell has inert gas structure

common features: low enthalpies of fusion and vaporization, good insulators, solids can be soft or brittle, if brittle, often transparent and cleave rather than deform

Front 10

ionic bonds

Back 10

one atom losses its valance electrons and another atom acquires the electrons

solid materials with ionic bonds generally are: hard, good insulators, transparent, brittle and tend to cleave rather than deform bc bonds are strong, materials have high melting points

Front 11

metallic bonds

Back 11

an aggregate of atoms gives up the electrons which can move quite freely. positive ions surrounded by cloud of electrons.

common features: good electrical and thermal conductors, opaque, relatively ductile and malleable

Front 12

ductile

Back 12

solids ability to deform under tensile strength--often characterized by the ability of the metal to be stretched

Front 13

malleable

Back 13

ability to deform under compressive strength--ability to form thin sheet by hammering or rolling

Front 14

secondary bonding

Back 14

when a molecule with a covalent bond has an electrical imbalance bc the electrons spend more time in a particular region results in an electric dipole.

van der waals bond and hydrogen bond

Front 15

van der waals bond

Back 15

weak bond between molecules due to electric dipoles

Front 16

hydrogen bond

Back 16

special dipole-dipole interaction between a neg charge hydrogen atom and an electronegative atom such as oxygen

Front 17

biomaterials

Back 17

synthetic materials used in the body

Front 18

dental biomaterials

Back 18

synthetic materials used in the mouth

Front 19

biological materials

Back 19

materials (tissues) that occur in the body (i.e. enamel, dentin, and bone).

Front 20

biomaterial applications-clinical specialty areas

Back 20

restorative dentistry, prosthodontics, laboratory, pediatrics, endodontics, orthodontics, oral surgery, periodontics

Front 21

SI Derived Units

Back 21

1.frequency-hertz

2. force-newton

3. pressure, stress-pascal

4. energy,work, quantity of heat-joule

5. celsius temp-degree celsius

Front 22

1.0 Ib=4.448 N

1.0 MPa=145 psi

1.0 MPa=.102 kg/mm^2

1.0 Ib=.4536 kg

T(k)=273+T(C)

Liter=measure of volume equal to 1000 cm^3

Back 22

A

Front 23

Angstrom

Back 23

unit of length to 10^-10 or 0.1 nm. sometimes used to express wavelengths of visible light, UV light, gamma rays, and x-rays

Front 24

SI Units continued

Back 24

length-meter

mass-kg

time-sec

electric current-A

thermodynamic temp-K

Amount of substance-mol

luminous intensity-Cd