Bonding Principles Flashcards
What are the three different materials that make up the adhesive joint
- Adhesive (middle)
- Tooth Structure
- Composite
The tooth structure is (hydrophilic/hydrophobic) while the composite is (Hydrophilic/hydrophobic)
hydrophilic…hydrophobic
What is the middle layer in the adhesive joint
the adhesive
How many surfaces (or adherents are in the adhesive joint
2
Who was the first dentist to use adhesive dentistry and acid etched enamel
Michael Buonocore
What did Dr. Ray Bowen discover
the 1st Bis-GMA matrix for composite resin
What is the substrate of tooth-to-resin adhesion
enamel and dentin
Enamel is what percent mineral by weight? Organic?
95%…4%
Is enamel completely hydrophobic like resin
no- but if fairly hydrophobic
(T/F) Hydroxyappatite forms prisms which makes up enamel
t
Dentin is what percent mineral by weight? Organic?
70%…20%
Which is more hydrophilic, enamel or dentin
dentin
(T/F) Dentin is a fairly static substrate with age
F- its always changing and thus is dynamic
Dentin has a __ structure
tubular
Dentinal tubules contain…
- Odontoblasts (1/3rd into the tubule)
- Fluids
- Nerves
Peritubular dentin is (more/less) mineralized than interlobular dentin
more
Intertubular dentin is rich in __ and is ideal for what?
collagen fibers… hybridization
(peritubular/intertubular) dentin makes up the bulk of dentin
intertubular
Current adhesives provide bonding to (hydrophilic/hydrophobic) substrates
both
The old classification system of adhesives was based on…
-Time of appearance in the market
What is the current adhesives classification system
- How many clinical application steps there are
- Underlying adhesive strategy (i.e etch and rise v.s self etch) etc
In a self etch system the acidic nature of the __ is integrated
monomer
Another word for etch is…
conditioner
Etch is an acid that performs two roles, what are they
- clean and prepare the surface
- Remove smear later and mineral from the surface
The primer is (hdrophyilic/hydrophobic)
both it is amphipathic
The primer is made up of
monomers and solvent carriers
What does the primer infiltrate
The exposed collagen network
The role of the primer is to displace the __ and link to __
moisture…hydrophobic adhesive
The adhesive is made of
hydrophobic resin monomers
The role of the adhesive is to…
provide links to the composite resin
For etch and rinse systems there are two different types which vary in
the number of steps performed by the dentist
The 2 step etch and rinse system involves
Etch (conditioner) + Primer/adhesive
The 3 step etch and rinse system involves
Etch + Primer + Adhesive
Other that the etch and rinse system, what is the other adhesion system
Self etch
Describe the 2 step self etch system
self etching primer + adhesive resin
Describe the 1 step self etch system
Etch/primer/adhesive all in one
What is a negative about the 1 step self etch system
bad shelf life
What is the hybrid layer
where the collagen fibers and adhesive monomers come together
(T/F) Etching of enamel and dentin must be performed to achieve adhesion with resin
t
What are three different substances used for etching
acids, lasers, and air abrassion
Who developed the acid etch technique?
Buonocore
Acid etch time depends on
the pH (conc. of acid)
(T/F) Etching removes the smear layer and closes the dentin tubules
F- it opens the dentin tubules
There are 4 different types of acids used for etching there are 2 organic and two inorganic what are they?
Organic
- Citric acid
- Malic acid
Inorganic
- Nitric acid
- Phosphoric acid
The effect of the acid etch depends on what factors
- Type of acid
- Acid conc. and pH
- Etching time
- Form of etchant (i.e gel, aqueous, etc)
- Rinse time
- Method of activation of the etchant (i.e rubbing)
- Chemical composition and condition of enamel
- Whether enamel is instrumented before etching
Etching primarily removes (inorganic/organic) material
inorganic
(T/F) acid etch results in an increase in surface area for enamel but not dentin
f- increases SA in both enamel and dentin
(superficial/deep dentin) has larger tubules
deep
(Superficial/deep) dentin has a greater amount of intertubular dentin verses peritubular dentin
superficial
(Superficial/deep) dentin has a greater amount of peritubular dentin verses peritubular dentin
deep
Primers are needed in (dentin/enamel)
dentin
(Superficial/deep) dentin has higher bonding strength
superficial
Primers contain bifunctional __ such as __ that are dissolved in __
monomers…HEMA…solvents (acetone, ethanol, etc)
What is the purpose of the solvent in the primer
they are highly volatile and displace water from the dentin
Adhesives have a (low/high) viscosity
low
Adhesives serve as __ retention
micromechanical
Adhesives are (hydrophobic/hydrophylic)
phobic
What is the role of adhesive resin
stabilizes the hybrid layer
What does the adhesive resin form
resin tags
What are two hydrophobic and highly viscous adhesive resins
Bis-GMA and UDMA
What are two hydrophylic and less viscous adhesive resins
TEG-DMA and HEMA
The hybrid layer is composed of…
resin, collagen, and partially demineralized dentin
Steps to apply etchant
- Apply to a clean, dry tooth
- Apply 1 mm beyond the margin
- Apply to enamel first then dentin (15 seconds on enamel)
- Rinse
Primer application
- Cover all etched surface
- Apply many coats
- Evaporate solvent by air thining
Adhesive application
- Paint even coat
- Air thin
- Light polymerize for 20 sec
