16 - Enamel and Dentin Adhesion (Bonding Part 1) INCOMPLETE

Question 1

___: Etching both the enamel and dentin for increased adhesion

Answer 1

Total Etch

Question 2

___: Etching only the enamel (avoiding the etching of the dentin-usually
done in order to maintain the smear layer)

Answer 2

Selective Etch

Question 3

___: No etchant is used. The bonding agent has primers that etch the
enamel or dentin or both.

Answer 3

Self Etch

Question 4

___: Bipolar monomers that have a hydrophyllic molecule on one end of the chain,
and a hydrophobic acrylic group on the other end (hence bipolar)

Answer 4

Primer

Question 5

___: Usually either ethanol or acetone which serve to carry the suspended primers
deep into the wet dentin substrate and tubules

Answer 5

Solvent

Question 6

___: The bis-GMA or other resin based agents that bond to the
substrate

Answer 6

Bonding Agent (adhesive)

Question 7

: Layer of freshly cut dentin/debris lining the floor and walls of a
prep

Answer 7

Smear Layer

Question 8

___: The zone in which resin of the adhesive system micromechanically
interlocks with enamel and or dentinal collagen

Answer 8

Hybrid Layer

Question 9

___: This is pure bis-GMA resin that has been prevented from
polymerizing by the oxygen in the ambient air, and it will combine with the
unpolymerized bis-GMA resin of the subsequent resin addition, thereby serving to
unite the two increments.

Answer 9

Air Inhibited Layer

Question 10

what is adhesion

Answer 10

Adhesion is defined as the force that binds two
dissimilar materials together when in intimate
contact.

Question 11

what is adhesion in dentistry

Answer 11

In dentistry, it refers to the process of
attaching/bonding a restorative material to tooth
structure

Question 12

successful adhesion depends on what

Answer 12

1. Preparing the surface by removing
   plaque and debris
2. Acid etching with phosphoric acid to
   increase porosity and wettability
3. Applied bonding agents flowing into the
   porosities and creating resin tags( macro
   and micro tags) for micromechanical
   retention
4. Applied resin bonding chemically to
   underlying bonding agents (primary
   bond)

Question 13

intimate contact between ___ and ____ is crucial

Answer 13

adhesive and substrate

Question 14

what does the intimate contact between adhesive and substrate dependon

Answer 14

1. wettability of substrate surface
2. viscosity of adhesive
3. surface orughness

Question 15

Sufficient wetting of the
adhesive will occur only if
its surface tension is ___the surface free
energy of the adherend
(substrate).

Answer 15

LESS
THAN

Question 16

what has high surface energy: enamel or dentin

Answer 16

enamel

Question 17

what has low surface energyy: enamel or dentin

Answer 17

dentin

Question 18

what depicts how well the adhesive wets the surface

Answer 18

The contact angle, the angle between
the surface and a tangent line drawn to
the edge of the adhesive droplet
through the droplet itself, depicts how
well the adhesive wets the surface. The
lower the contact angle, the better an
adhesive will wet the surface and
enhance adhesion.

Question 19

Answer 19

Question 20

___ increases ability to be wet by a resin bonding agent, resulting in stronger bond

Answer 20

acid etching of enamel

Question 21

a ___ contact angle indicates good wetting as liquid spreads over surface

Answer 21

LOW

Question 22

a ___ contact angle indicates poor wetting as liquid beads on the surface like water on waxed car

Answer 22

HIGH

Question 23

what are mechanisms of bonding of resin-based materials to tooth structures

Answer 23

1. mechanical
2. absorpotion
3. diffusion
4. combination of previous three mechh

Question 24

what is the penetration of resin and formation of resin tags within tooth surface

Answer 24

mechanical

Question 25

what is a chemical bonding to inorganic component (HAP) or organic components (mainly type I collagen) of tooth structure

Answer 25

adsorption

Question 26

what is the precipitation of substances on tooth surfaces to which resin monomers can bond mechanicallly or chemically

Answer 26

diffusion

Question 27

how do the failures of adhesive joints occu

Answer 27

I. Cohesive failure in the substrate II. Cohesive failure within the adhesive III. Adhesive failure, or failure at the interface of substrate and adhesive.

Question 28

what is the dental adhesive system components

Answer 28

1. etchant 2. primer 3. bonding/adhseive resin

Question 29

what are the diferent classifications of adhesive systems

Answer 29

1. etch-and-rinse/total etch (3 and 2 step) 3. self etching (2 and 1 step) 3. universal (2/1 step) (also called multimode)

Question 30

enamel % minerals, organic content, and water

Answer 30

96% minerals 4% organic content and water

Question 31

what is a homogenous structures, predictable bonding, and excellent long term bonding durability

Answer 31

enamel

Question 32

Treatment of enamel with an ___ before placement of a restorative material.

Answer 32

acid

Question 33

who introduced enamel etching

Answer 33

Buonocore in 1950s

Question 34

what does etched enamel appear

Answer 34

frosty white when dried

Question 35

etching produces a rough surface into pits causing what

Answer 35

resin flows and forms rresin tags for micromechanical retention

Question 36

T/F: Etching follows completion of cavity prep and will follow base/liner placement, if indicated

Answer 36

TRUE

Question 37

what is first: enamel etching or primer/adhesive placement

Answer 37

enamel etching

Question 38

functions of acid etching

Answer 38

1. Leaves clean enamel surface which permits better wetting of surface, facilitates better adaptation of restorative material 2. Contact angle between adhesive and enamel is reduced=better wetting 3. Etch increases enamel surface energy 4. When a low viscosity adhesive is applied, it is drawn into the surface irregularities 5. acid attacks/decalcifies enamel leaving numerous microscopic irregularities (peaks and valey) 6. improve marginal seal of restoration 6. decreate effect of polymerizatino shrinkage of resin material by holding resin close to cavosurface and minimizing pull away effect as resin polymerizes and shrinks

Question 39

what chemical is etching material

Answer 39

35-37% phosphoric acid

Question 40

etching enamel/dentin contact time

Answer 40

10-15 seconds

Question 41

how is etching material supplied

Answer 41

supplied as gel by adding colloidal silica to acid

Question 42

acid etch applied for how long

Answer 42

15-30 seconds. rinse for about 20 seconds then dry

Question 43

how should enamel appear after acid etching

Answer 43

frosty white

Question 44

what should you do if contamination occurs (e.g., saliva blood etc)

Answer 44

re-etch

Question 45

what part of rod etches the best

Answer 45

rod ends etch better than sides

Question 46

what are rod core and interprismatic substance have been etched or preferentially decalcified over the rod sheath

Answer 46

because the rod sheath is more organic in composition

Question 47

acid attacks inorganic structures in enamel creating what

Answer 47

"peaks and valleys"

Question 48

is more or less organic material left behind in enamel etchign

Answer 48

more oreganic material left behind

Question 49

how do enamel rods eenhance retention

Answer 49

mechanical locks and greater surface content area (2000x)

Question 50

what enamel does not etch as readily as other

Answer 50

Enamel of primary teeth Teeth with high fluoride levels Enamel of older patients People who use whitening agents Uncut enamel Enamel adjacent to glass ionomer restorations

Question 51

why do enamel adjacent to glass ionomer restorations not etch readily

Answer 51

because they release fluoride

Question 52

what etching location is not as retentive and not as many peaks and valleys

Answer 52

sides of rods

Question 53

where do you sometimes place a bevel on preps to prevent this type of etching pattern form class 3, 4, 5

Answer 53

sides of rods

Question 54

ends of rods have surface irregularities of ___ microns deeps sides of rods have surface irregularitites of ___ microns dep

Answer 54

10-30; 5 so ends give better retention

Question 55

what type of etching pattern results when prism core and interprismatic substance are dissolved and prism sheath is left standing

Answer 55

TYPE I

Question 56

what is the best etch pattern

Answer 56

TypeI

Question 57

what results when the prism sheath is preferentially decalcified and rod core and interprismatic substance are left standing

Answer 57

type II

Question 58

what results when aprismatic enamel is etched, often a combo

Answer 58

type III

Question 59

what type of teeth are type III Etch done

Answer 59

primary teeth or gingival 1/3 of permanent teeth

Question 60

does type III produce as good retention as type I or II?

Answer 60

NO!

Question 61

can you have type I, II, or III all on the same tooth next to each other?

Answer 61

YES!

Question 62

CONTINUE SLIDE 29-32

Question 63

what are the two types of enamel bonding afgent

Answer 63

1. unfilled bisGMA resin 2. dentinal bonding agents (prime and bond NT)

Question 64

what is: Same chemically as filled resin, but no filler particles Mechanical retention

Answer 64

unfilled bisGMA resin

Question 65

what is: Developed for adhesion to dentin Chemical and mechanical adhesion to enamel also Attachment to enamel is stronger than unfilled bisGMA

Answer 65

dentinal bonding agents (prima nd bont NT)

Question 66

what is the current total etch technique

Answer 66

bonding agent appleid to both enamel and dentin

Question 67

bonding agents used for enamel bonding made from resins combined with what? why?

Answer 67

combined with dilutents to lower viscosity

Question 68

dentin % minerals, organic content, water

Answer 68

45% mineral 33% organic content 22% waterw

Question 69

what is a heterogenous structure with fair long term bonding durability

Answer 69

dentin

Question 70

what makes dentin a challenge when it comes to adhesive bonding

Answer 70

1. Dentine is a living tissue (50% HA, 30% collagen, 20% fluid) 2. Tubular nature of dentine (dentinal fluid) 3. Branching patterns in tubules, may enhance retention 4. Smear layer presence 5. Possible side effects on the pulp

Question 71

The ___ is created whenever tooth surface is cut with hand or rotary instruments

Answer 71

smear layer

Question 72

what is defined as any debris, usually calcific produced by reduction or instrumentation of enamel, dentine or cementum.

Answer 72

smear layer

Question 73

can bacteria trapper in smear layer can survive and multiply beneath restoration

Answer 73

YES

Question 74

if bacteria is retained in smear layer, what can happen?

Answer 74

1. lowers dentin permeability 2. decreases bond strength 3. lowers the effect of pulpal pressure on bond strength.

Question 75

how does over etching affect dentin

Answer 75

leads to weaker bond and sensitivity

Question 76

over drying of dentin leads to what

Answer 76

collapse of collagen and occlusion of tubules

Question 77

Answer 77

wet/moist dentin

Question 78

Answer 78

dry dentin

Question 79

Answer 79

over wet -> wet -> overdry

Question 80

when acid conditioning dentin, what should you avoid

Answer 80

avoid excessive long time contact of etching

Question 81

long time contact of etchant on dentin does what

Answer 81

depletes calcium, adversely affect the ionic bond achievable

Question 82

if you deplete the calcium to the point where the collagen rich zone of dentin becomes too thick, what happens?

Answer 82

becomes difficult for adhesive to penetrate

Question 83

SLIDE 42

Question 84

dentin bonding agent solvenst

Answer 84

acetone or aclohol or water

Question 85

SLIDE 43

Question 86

SLIDE 44

Question 87

SLIDE 45

Question 88

SLIDE 46

Question 89

bond strength of enamel

Answer 89

25-40 MPa

Question 90

bond strength of dentin

Answer 90

20-25 MPa

Question 91

pulpal protection resins

Answer 91

1. CaOH - stimulates (irritates) to enable pulpal repair (ultrablend here at school) 2. glass Ionomer products (Fuji)

Question 92

always place a base/liner when dentin thickness is what

Answer 92

1 mm or less

Question 93

microleakage following etching an opening tubules is a problem. therefore what must you do

Answer 93

seal dentinal tubules

Question 94

do you need a THICK layer of liner for pulp

Answer 94

no! thin!

Question 95

do you need thermal protection of pulp for composites

Answer 95

no

Question 96

do you need a barrier for ehcmical irritation or stimulate a healthy pulpal response for the pulp

Answer 96

yes

Question 97

T/F: DO use a cavity varnish or eugenol containins compounds (interferes with bond)

Answer 97

DO NOT!!

Question 98

pulpal protection is placed on what part of dentin

Answer 98

deepest part of dentin

Question 99

where do you NEVER place a base?

Answer 99

on enamel or retention areas

Question 100

glass ionomer product advantages

Answer 100

1. fluoride ion release into surrounding tooth structure 2. Chemical bond to tooth structure 3. Increased strength 4. Radio-opaque 5. Biocompatible (DO NOT place within 1mm of pulp) 6. Can potentially improve marginal integrity and reduce microleakage

Question 101

do not acid condition the enamel before what

Answer 101

before the base has reached its initial set (2 min 20 seconds)

Question 102

should you avoid etchant contact with the glass ionomer base

Answer 102

yes

Question 103

what attaches to tooth structure for greater stability

Answer 103

glass ionomer bases