Bonding

Question 1

What is the definition of adhesion?

Answer 1

a substance that is capable of strongly and permanently holding two surfaces together

Question 2

what is mechanical adhesion?

Answer 2

when you have a rough surface lots of peaks and spikes, retention, one material fills in those irregularities creating a lock, NO glue, connected byt he geometry

Question 3

What is retentive interlocking?

Answer 3

when you have one material with bumpy or jagged edges and the other material fills in all of those

Question 4

what is chemical or true adhesion?

Answer 4

use chemistry on one material to form a chemical link with another material (example having a COO group in a material that reacts with the Ca in tooth structure)

Question 5

Can chemical and mechanical adhesion co exist in dentistry?

Answer 5

yes

Question 6

What are some key steps for good bonding?

Answer 6

-clean adhesion
-good wetting
-intimate adaption
-bonding
-complete curing

Question 7

what are the three steps for most types of bonding?

Answer 7

conditioning (or etching)
primer
adhesive

Question 8

why do we do etching/conditioning during bonding?

Answer 8

removal of the smear layer

Question 9

what is typically used to etch?

Answer 9

37% phosphoric acid

Question 10

what is the purpose of calcium chelators in etching?

Answer 10

EDTA
removed or modifies the smear layer without demineralizing the surface of the dentin

Question 11

what are examples of funcitona monomers and what are they used for?

Answer 11

10-MDP, 4META, phenyl P
used for self-etch

Question 12

what is the consequence of acid-etch?

Answer 12

converts smooth surface to rough
creates micropores
increases surface energy and wettability

Question 13

acid ethcing prepares tooth surfaces for _______ locking

Answer 13

micromechanical

Question 14

what does a primer used for?

Answer 14

To increase the diffusion of resin into moist/demineralized dentin after etched

Question 15

what are some common primers?

Answer 15

HEMA and 4-META

Question 16

what are the bi-functional agent of primers?

Answer 16

• Hydrophilic end with affinity for exposed collagen fibrils
• Hydrophobic end with affinity for resin/adhesive

Question 17

what is adhesive resin?

Answer 17

Solvent-free (hydrophobic) low-viscosity resin that is applied over the primer

Question 18

what does adhesive resin interact with?

Answer 18

Interacts and copolymerize with the restorative material (link between primer and “composite”)

Question 19

what are some examples of unfiled or lightly filled

Answer 19

Bis-GMA, UDMA, TEGDMA

Question 20

what is the main difference between etch and rinse/total etch and self etch?

Answer 20

Main difference is that the Etch-and-Rinse technique always uses
acid-etch step

Question 21

etch and rinse strategy uses:

Answer 21

ACID ETCH
2 OR 3 step process
* Etching + Primer + Bonding
* Etching + Primer/Bonding

Question 22

what is the self etch strategy? what does it not use and what does it use instead?

Answer 22

no acid etch
instead using functional monomer(carboxyl or phosphate) for PARTIAL demineralization

Question 22

what is the primary adhesion mechanism for etch and rinse strategy?

Answer 22

mechanical locking

Question 23

how many steps are involved with the self edge strategy?

Answer 23

2 or 1

Question 24

what does the functional monomer interact with in the tooth structure?

Answer 24

hydroxyapatite

Question 25

what does the two step self edge include?

Answer 25

2 steps: Acid/Primer + Adhesive (gold standard)

Question 26

what is the primary adhestion mechanism for self etch?

Answer 26

mechanical locking /
chemical bond

Question 26

what does the one step self edge include?

Answer 26

Acid/Primer/Adhesive

Question 27

how is self etch categorized?

Answer 27

by etching strength (1 is strong, over 2.5 ultramild)

Question 28

what are some challenges of adhesion?

Answer 28

• Retention: Keep the bond for the duration of service
  -No leak (no fluids in between the bonded interface)
  -Bacteria, fluids can penetrate the interface
  -No Retention (Sensitivity, failure, staining, 2nd caries, inflammation)
  -degradation, technique, handing

Question 28

what is universal or multi mode adhesive?

Answer 28

• Most simple-to-use adhesive. Versatile.
• Available as:
• ER mode (acid etching + universal bottle)
• SE mode (universal bottle) - all included

Question 29

what % of restorations fail?

Answer 29

<60% of composite restorations failure within 10 years

Question 30

why is bonding to dentin harder?

Answer 30

the presence of water in dentin lowers the surface energy

Question 31

what is the challenge with moist vs dry dentin?

Answer 31

• Water keeps collagen expanded and retains
  spaces for resin infiltration
• Dry collagen collapses and obstructs the resin
  from reaching the dentin
  (Presence of moist/wet dentin
  is needed to achieve
  successful dentin bonding)

Question 32

what is another challenge to bonding to dentin?

Answer 32

The higher the tubule density, the lower the bond strength values of
the dentin adhesives

Question 33

what are some examples of stabilizing bonded interface?

Answer 33

-consepsis (2% chlorhexidine, disinfectant and MMP inhibitor)
-Gluma (5% Glutaraldheyde, key cross linking agent)

Question 34

what are the major functions of Stabilizing Bonded Interface?

Answer 34

• Antimicrobial Activity & Inhibition of
  Metalloproteinases;
• Gluma – Crosslink and stabilize collagen