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Flashcards in Bonding Agents Deck (31)
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1
Q

What is the mechanism of Adhesion (resin-based)?

A

Replacement of minerals from hard tissue by resin monomers micromechanically interolocked

2
Q

Why is enamel more predictable to bond to?

A
  • More homogenous structure
  • High inorganic content
  • Higher surface energy
3
Q

Why is dentin less predictable to bond to?

A
  • high variability

- higher organic content

4
Q

What is the composition of enamel?

A
  • 86% Inorganic
  • 12% Water
  • 2% Organic
5
Q

What does etching do?

A
  • Creates microspores
  • 5-50 microns deep
  • Increases surface energy
  • Increases wettability
6
Q

What is the composition of Dentin?

A
  • 50% Inorganic
  • 25% Organic
  • 25% Water
7
Q

What is sclerotic dentin?

A
  • Normal Aging
  • Abrasion
  • Erosion
  • Hypermineralization
  • Less receptive to bonding
8
Q

What is reparative dentin?

A
  • Results from caries/dental procedures
  • Hypermineralization
  • Less receptive to bonding
9
Q

What percent does the dentin smear layer reduce dentin permeability?

A

86%

  • Produced by instrumentation
  • Composition: cut dentin debris, bacteria
10
Q

How thick is the dentinal smear layer?

A
  • 0.5 - 5.0 microns
  • Will not wash off
  • Weak bond to tooth
  • Very soluable
11
Q

What does a 4th generation bond system look like?

A
  • Conditioner (etchant)
  • Primer (hydrophilic)
  • Adhesive (hydrophobic)
  • Etch and Rinse

Example - Optibond FL, Scotchbond multi-purpose

12
Q

What does a 5th generation bond system look like?

A
  • Attempt to simplify…
  • Reduce number of bottles
  • Etch and Rinse…
  1. Conditioner (etch)
  2. Combined primer and adhesive
  • More susceptible to hydrolysis over time…

Example: Optibond solo

13
Q

What does a 6th generation bond system look like?

A
  • No phosphoric acid!
  • Combined conditioner and primer
  • Clearfil SE!
  • Separate adhesive
14
Q

What does a 7th generation bonding agent look like?

A
  • “All in one”
  • Combined conditioner, primer and adhesive
  • One step
  • No mixing
15
Q

What does conditioner (etch) do to the tooth?

A
  • Chemical alteration of the surface
  • ie: phosphoric, citric, maleic, nitric
  • Removes dentinal smear layer
  • Exposes collagen fibrils
  • Simultaneous enamel etch
  • Rinse
  • Keep moist
16
Q

What does a primer (wetting agent) do?

A
  • Hydrophilic monomers
  • Displaces water
  • Promotes infiltration into collagen
  • Lightly air dry
  • Transforms hydrophilic to hydrophobic
  • This is better for composite which is hydrophobic!
17
Q

What does adhesive resin do?

A
  • Chemically binds to primer

- Links primer to resin composite

18
Q

What is the hybrid layer?

A

The hydrophilic resin infiltrated surface layer of collagen fibers in demineralized dentin

19
Q

A separate enamel is etch is more predictable then self etches…T/F?

A

True

20
Q

Study that supported optibond FL use (3 Step)…

A
  • Van Meerbeek Study - 100% retention at 3 years for NCCLs

- Boghosian - 97% at 13 years

21
Q

What do studies show about etch and rinse (two step)?

A
  • Optibond Solo
  • Swift - 93% retention at 3 years for NCCL
  • More susceptible to hydrolysis at hybrid layer
22
Q

If you are using a self etch bond system are you going to use phosphoric acid?

A

No!

23
Q

Have controlled clinical studies found any difference in post op sensitivity between etch and rinse and self etch bonding systems?

A

No!

24
Q

Does research support better bond strength with Clearfil SE it if is refrigerated?

A

Yes!

More Shear Bond Strength….

25
Q

What do studies show about a self etch 2 step Clearfil SE to NCCLs?

A
  • Van Meerbeek - 100% retention at 2 years
  • Van Dijken - 98% at 8 years
  • Peumans - 86% at 13 years
26
Q

According to systematic reviews, what restoration type has the lowest failure rate regarding cervical restorations?

A
  1. Glass Ionomers
  2. 3-Step Etch and Rinse
  3. 2-Step Self Etch
  4. 2-Step Etch and Rinse
  5. 1-Step Self Etch

According to the Schwendicke Systematic Review

27
Q

What common denominator do two-step etch and rinse and one step self-etch bonding systems have in common? Is this good?

A

Acidic Monomers -

They are not good! Weaker bond…More susceptible to hydrolysis

28
Q

What are MMPs?

A

Matrix Metalloproteinases

29
Q

Where are MMPs found in teeth?

A

Naturally occurring in collagen in tooth structure

30
Q

What induces MMPs?

A

Caries

Phosphoric Acid

31
Q

What inhibits MMPs?

A

Chlorhexidine

One could…

Apply CHX after acid etching, acidic conditioner, rinse, dry, CHX, dry, primer, dry, adhesive, cure

According to a systematic review by Gostemeyer - Beneficial effect is NOT supported by evidence

Impact of disinfection remains unclear