Intro to Biomaterials

Question 1

3 main classes of materials

Answer 1

metals, ceramics, and polymers

Question 2

____ and ____ are considered polymer-ceramic

Answer 2

composite resin; glass-ionomer

Question 3

____ are considered metal-ceramic

Answer 3

metal-ceramic crowns

Question 4

material used to construct artificial organs, rehabilitation devices, or prostheses and replace natural body tissues, without causing any harm or negative reactions

Answer 4

biomaterials

Question 5

synthetic biomaterials

Answer 5

composites

silicone impression materials

Question 6

natural biomaterials

Answer 6

alginates

hydrocolloids

Question 7

tissue-engineered biomaterials

Answer 7

stem cells
replacement tissues (growing a tooth from a bud)

Question 8

metals are considered ___, ____, and ____

Answer 8

hard, ductile (tough), strong

Question 9

ceramics are considered ___, ____ and ____

Answer 9

hard, brittle, strong

Question 10

polymers are considered ____, ____, and ____

Answer 10

soft, ductile (tough), weak

Question 11

____ and ____ have high processing temperatures

Answer 11

metals; ceramics

Question 12

____ tend to have lower processing temperatures

Answer 12

polymers

Question 13

polymers tend to be used as ____ processing materials

Answer 13

direct

Question 14

metallic elements have ____ in their outer shell

Answer 14

1,2,3 electrons

Question 15

____ are key to metallic bonds and are ____ bound to nucleus

Answer 15

electrons; loosely

Question 16

electrons have free ____; ___ and ____ conductivity and ductility-bend without breaking

Answer 16

mobility; thermal and electrical

Question 17

mixture of 2 or more metals

Answer 17

metal alloys

Question 18

metal alloys include ___ and ____

Answer 18

cast metals for crowns; amalgams

Question 19

pure metal is ____; atoms can slide

Answer 19

ductile

Question 20

solid solution alloy is ____ but less _____

Answer 20

stronger; ductile

Question 21

____ must be made to resist deformation; modified to impede dislocations

Answer 21

strengthening noble metals

Question 22

noble metals include

Answer 22

Au, Ag, Pd, Pt

Question 23

___ and ___ bonds are associated with ceramics

Answer 23

ionic; covalent

Question 24

ionic and covalent bonds are ____ than metallic bonds

Answer 24

stronger

Question 25

covalent bonds are ____ than ionic bonds

Answer 25

stronger

Question 26

ionic bonds have an ____ and ____

Answer 26

electron donor; electron acceptor

Question 27

covalent bonds have ____ shared electrons

Answer 27

equally

Question 28

ceramics are a mixture of ___ and ____ elements

Answer 28

metallic; non-metallic

Question 29

3 metallic oxides most common ceramics in dentistry

Answer 29

SiO2, Al2O3, K2O

Question 30

____ is the building block

Answer 30

SiO4 tetrahedron

Question 31

most dental ceramics are ____ or _____

Answer 31

semicrystalline; polycrystalline

Question 32

SiO4 tetrahedron is the building block of ____

Answer 32

dental porcelain

Question 33

porcelain is primarily a ____ with some ____ residuals

Answer 33

glass; crystalline

Question 34

porcelain is processed by ____ or ____ at high temperatures

Answer 34

sintering; melting

Question 35

characteristic polymer bonds are ____ bonds with high _____; long molecules composed principally of ____ elements

Answer 35

covalent; molecular weight; nonmetallic elements (C, O, N, and H)

Question 36

polymers are ____ long chains like cooked spaghetti that derive strength and properties from the ____

Answer 36

entangled; entanglement

Question 37

polymerization process

Answer 37

1. light activation of initiator molecule (I) to generate a free radical (R) 2. initiation of a monomer to generate a free radical 3. propagation of free radical with four monomers 4. termination of free radical

Question 38

polymerization can be initiated by ____, ____, and ____

Answer 38

light; heat; chemical mixing

Question 39

a _____ utilizes light to generate a free-radical

Answer 39

visible light initiator

Question 40

free radicals will initiate _____

Answer 40

methacrylate polymerization

Question 41

_____ (yellow) absorbs visible light and interacts with ____ to generate free radicals

Answer 41

CQ ; DMAEMA

Question 42

four stages of chain reaction polymerization

Answer 42

activation- free radical initiation initiation- free radical combination with monomer unit, double bond opening propagation- chain growth, volume decrease, shrinkage termination

Question 43

monomer functional groups

Answer 43

monomethacrylates- linear chains | dimethacrylates- branched and cross-linked

Question 44

polymerization allows for ____ processing for ____ placement

Answer 44

in vivo; direct

Question 45

metals are indirect placement with high processing temps, except ____

Answer 45

amalgam

Question 46

ceramics are indirect placement with high processing temps except _____

Answer 46

cements

Question 47

polymers are direct placement with low processing temps except _____

Answer 47

indirect composites

Question 48

uses of polymers in dentistry

Answer 48

provisionals (temporary crowns) adhesives restoratives registration materials (impression materials)

Question 49

provisionals are ____

Answer 49

linear

Question 50

adhesives are ____

Answer 50

cross-linked

Question 51

restoratives are ____

Answer 51

cross-linked

Question 52

physical mixtures of metals, ceramics, and/or polymers

Answer 52

composites

Question 53

By knowing the phases present in the structure of any material and interfacial interactions, it is possible to predict the overall properties fairly well

Answer 53

rule of mixtures

Question 54

dental composite dispersed phase

Answer 54

glass fillers

Question 55

dental composite matrix phase

Answer 55

monomer resin

Question 56

fillers are chemically bonded to ____ phase to improve properties

Answer 56

resin

Question 57

what happens when you increase filler volume

Answer 57

increase strength, increase modulus, increase viscosity, decrease shrinkage

Question 58

what happens when you increase filler size

Answer 58

increase surface roughness

Question 59

filler types

Answer 59

``` silicate glass (larger) colloidal silica (smaller) ```

Question 60

filler amount

Answer 60

75-80 wt%

Question 61

mass property measured in weight/unit volume

Answer 61

density

Question 62

relative density or density of material/density of water

Answer 62

specific gravity

Question 63

most things ____ when heated and ____ when cooled (thermal expansion)

Answer 63

expand; contract

Question 64

thermal expansion measured in ____

Answer 64

LCTE (linear coefficient of thermal expansion)

Question 65

thermal expansion trend

Answer 65

ceramics < metals < polymers | tooth < amalgam < composite

Question 66

teeth are ____ due to high mineral content

Answer 66

insulators

Question 67

metals have high ____ so they need a ____ like base

Answer 67

thermal conductivity; thermal insulator

Question 68

composites have ____ thermal conductivity so they do not need an insulator base

Answer 68

low

Question 69

metal restorations conduct ____ while composites and ceramics are electrical ____

Answer 69

electricity; insulators

Question 70

optical properties include:

Answer 70

color, translucency, gloss, and surface texture

Question 71

3 dimensions of color

Answer 71

hue, value, and chroma

Question 72

2 objects that appear the same color under one light source and different under another light source; have different spectral characteristics

Answer 72

metamerism

Question 73

color is defined in a _____

Answer 73

3D coordinate system