Adhesion Flashcards
What does acid-etch do
Removes smear layer
What happens to the collagen after placing bond
collagen network becomes more active
GIC has been used to ……. ……. process
control caries
Biodentine is a massive outflow of …..
calcium hydroxide
Pulpal actions of calcium hydroxide
increases mineralization
Polymers is a large molecule repeated of structural units connected by covalent chemical bonds, they are used in dentistry for….
- composites
- acrylic dentures
- alginate
- silicone impression (putty)
2 main methods for synthesising polymers
- Addition
- Condensation
We conduct ……… when we use a ……. to ……… dental composite
polymerisation
light
cure
Addition of polymerisation is the joining of ….. …….. to form a …….. larger molecule
two molecules
third
3 steps of Addition polymerisation
- Initiation
- Propagation
- Termination
Incremental curing is composite is required due to….
- the limited cure depth
- reduce shrinkage stress
- “the depth of cure”
Combination of …… and …… is used to improve the degree of polymerisation
heat
light
Condensation polymerisation is the reaction between …. …….. and then a small ……… is ………..
two molecules
molecule
eliminated
Why are composites so widely used?
List 4
- withstand the environment in the oral cavtiy
- easily shaped to anatomy of tooth
- match tooth colour
- bond directly to tooth tissue
3 Contraindications of composite
- poor isolation
- larger posterior restorations
- bruxism
2 Major constituents for composite
- high molecular weight monomers
- fillers
What reduces viscosity in resin monomer
diluent monomers (minor component)
Inhibitors are a minor component in resin monomers which are added to prevent ……… ………. during storage, handling and placement
premature polymerisation
What particles are seen to improve the properties of composite
smaller particles
The higher the filler content the …….. the polymerisation ………..
lower
shrinkage
Filler particles are important in composite because they……
list 4
- reduce polymerisation shrinkage
- improves surface hardness
- improves mechanical properties (elasticity, strength)
- improves aesthetics
Silane coupling agents …….. the adhesion between the …… and the ……… matrix
enhances
filler
polymer
Polymerisation shrinkage plays a significant role in restoration failure which can lead to …. 4 things
- gap formation
- secondary caries formation
- marginal leakage
- post-operative sensitivity
The maximum thickness of a layer of composite that can be cured is the measure of ………. … ……….
“depth of cure”
On curing a limited thickness of composite undergoes ………… so composites have a limited …… ……… …….
polymerisation
depth of cure
3 types of composites
- Nanocomposites
- Flowable composites
- Bulk filled composites
4 Properties of Nanocomposites
- nano sized particles (very small)
- low polymerisation shrinkage
- good aesthetics
- high flexural strength
Nanocomposites have a very smooth surface which makes them have a high polish retention which makes them good for (5)
- long lasting aesthetics
- reduced plaque adhesion
- reduced risk of secondary caries
- reduced risk of gingival inflammation on class V
- high oral comfort
Flowable composites gives rises to ….. …….. ……..
high contraction stresses
Flowable composites have a reduced amount of …… ……. making them a lot more …….. but with a higher shrinkage rate
filler content
flexible
Flowable composites are now recommended to only us as 3 things
liners
fissure sealants
small restorations
What does pre-warming composite do
Enhances flow of composite as viscosity decreases , better for placement
What are bulk-filled composites
- composites that do not require incremental curing
- can cured up to depths of 4-5mm
