Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biomaterials > Exam 3: Resin Composites > Flashcards

Exam 3: Resin Composites Flashcards

1
Q

procedure of composite restorations

A
  1. caries removed and etched with acid
  2. adhesive is applied
  3. resin placed in increments or in bulk
  4. resin cured
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

main component of resin composites

A

dimethacrylate monomer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

dimethacrylate provides…

A

polymerization mechanism and thus setting mechanism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

a solid that contains two or more distinct constituent materials at the
microlevel

A

composite

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

4 essential components of composite materiasl

A
  • organic polymer matrix
  • inorganic filler particles
  • coupling agent
  • initiator/accelerator system
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

limitations of composite

A

-shrinkage on polymerization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

shrinkage on polymerization leads to…

A
  • stresses at bonded interfaces
  • lack of marginal adaptation
  • microleakage
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

function of inorganic filler in composite

A

reinforcement, radiopacity, control of shrinkage, enhance mechanical properties

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

coupling agents are typically…

A

silane compounds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

minor components in composite include…

A

pigments, polymerization stabilizers, UV absorbers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

bis-GMA is a monomer with…

A
  • 1 methacrylate at each end

- a rigid central part to provide mechanical properties

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

main drawback of bis-GMA

A

high viscosity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

why does shrinkage occur in polymerization?

A

molecules have to approach their neighbors to form

chemical bonds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

The ______ that are produced during setting of dimethacrylate resins produce
_______

A

cross-linking reactions, volumetric shrinkage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

approaches to low shrinkage resins

A
  • low shrink methacrylate monomers

- silorane chemistry

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

methacrylate monomers have _________

A

Increased distance between the methacrylate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

silorane chemistry utilizes

A

ring-opening polymerization

18
Q

inorganic fillers…
___ strength on compression
___ surface hardness/wear resistance
____shrinkage

A

increase, increase, decrease

19
Q

inorganic fillers…
contribute to _____
____ control of exothermic heat
may ____ confer radiopacity

A

esthetics/translucency, increase, increase

20
Q

The filler is _____ than the resin.

A

stronger and more rigid

21
Q

Silanes are relevant to the long-term _____ of the composite

A

hydrophobicity

22
Q

inorganic filler variables

A

filler composition, filler content, filler particle size

23
Q

filler composition made by grinding process, rough surface and hard to obtain/maintain smooth surface, very hard

A

crystalline silica or quartz mineral

24
Q

filler composition that has very poor handling if used alone, modified w pre-polymerized resin, excellent polishability

A

fused silica

25
Q

filler composition made by grinding to desired particle size, limited on how fine grind can be

A

glasses (Barium or Strontium glass)

26
Q

filler composition that is approximately spherical particles, good polishability

A

sol-gel filler (zirconia-silica)

27
Q

size of macrofillers; type

A

100-10um; crystalline silica/quartz mineral

28
Q

size of small/fine fillers; type

A

10-0.1 um; melted glass

29
Q

size of microfillers; type

A

0.1-0.01um; agglomerated

30
Q

size of nanofillers; type

A

0.1-0.005um; zirconia/silica

31
Q

classification of composites based on flow properties (by incr. viscosities)

A

sealants, flowable, anterior, universal, packable

32
Q

sealants are based upon _______ and contain ______.

A

dimethacrylates resins, none or small amounts of inorganic

fillers

33
Q

flowable composites have ______ and are mostly used for _______, sometimes as ____

A

shear thinning property, anterior/cervical restorations, sealants

34
Q

anteriors are mostly _______, used in Class ___ restorations for its ____ properties

A

microfilled composites, Class III and IV, esthetics

35
Q

universal/multipurpose are _______ composites, have good ______ and very good

A

hybrids and nano; polishability; mechanical properties

36
Q

universal/multipurpose composites can be used in ______

A

anterior or posterior restorations

37
Q

Packable composites are almost completely out of the market because…

A

they did not match the

desired initial handling properties

38
Q

challenges of bulkfill composites…

A

polymerization shrinkage, viscosity, depth of cure

39
Q

attempts to approach viscosity in bulkfill

A
  • heating composite

- incorporating agents to modify viscosity

40
Q

attempts to approach depth of cure in bulkfill

A

-germanium-based initiator that has a different absorbance spectrum

41
Q

attempts to approach polymerization shrinkage

A

-introduce monomers that minimize stresses acting as modulators

42
Q

Resin composites that can be used for restorations using a single increment

A

bulk-fill composites

Biomaterials (18 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions