Resin-Based Composites

resin-based composite composition

1. Resin Matrix (organic phase)

2. Filler particles (inorganic phase)

3. Coupling agent

4. Initiators

5. Inhibitors

6. Pigments

what is the organic phase of the resin based composite

resin matrix

what is the inorganic phase of the resin based composite

fillers

1. Resin Matrix (organic phase) is made up of

polymerizable dimethacrylate monomers

2. Filler particle (inorganic phase) is made up of

glass, quartz, silica, or ceramic particles

3. Coupling agent

silane

chemically bonds filler to resin

4. Initiator/accelerator

chemical or light activated, starts polymerization

5. Inhibitor

prevent premature polymerization and increase the shelf-life

what are the 3 common resin monomers

Bis-GMA
TEGDMA
UDMA

filler is ____-____% by volume

30-70%

fillers provide ____ and _____

strength and resistance

what provides radiopacity in the resin

filler

by Ba, Sr, Zn, Zr oxides

filler particles provide

strength and wear resistance

reduced polymerization shrinkage

reduced water sorption

radiopacity

control of viscosity

coupling agent (silane) improves

mechanical strength

wear resistance

what are the 3 type of initiators

chemical cure (mix 2 things together and they automatically cure)

light cure (blue or puple light)

mixed of both

inhibitors increase ___ ___ and ____ ____

working time

shelf life

high filler content ____ stiffness and strength

increases

high filler content ______ polymerization shrinkage

decreases

high filler content ______ water sorption

decreases

handing properties are influenced by

resin viscosity and filler loading and size

flowable has ____ viscosity

low

packable has ___ viscosity

high

radiopacity is achieved by adding heavy ____ ____ to fillers

metal oxides

why must resin-based composites present radiopacity

to be able to differentiate restorations from actual tooth structure

also allows us to detect if there are recurrent caries, overhang, or defects

Type 1 classification RBC

occlusal restoration

Type 2 classification RBC

non-occlusal restorations and luting agents

Class 1 RBC

self-cured

Class 2 RBC

light cured (intra or extraoral)

Class 3 RBC

dual-cured (self and light)

this filler (40-50nm, smallest) has excelent polish and esthetics, lower strength, and is used in low-stress esthetic areas

microfil

this filler (intermediate sized) balances strength and esthetics and is suitable for anterior or posterior restorations

mini/midifil (microhybrid)

this filler (smallest and largest) has high polishability and strength and has excellent wear resistance, is used in the posterior teeth

nanofil

this filler is a combination of conventional fillers, and nonoparticles and combines strength of microhybrids and esthetics of microfils

nanohybrid

smaller fillers have _____ light transmission

better

where is packable used

posterior teeth

downsides to packable

hard to adapt to

where is flowable used

non load-bearing areas

pros of flowable

easy to adapt to the preparation

where are conventional (universal) composites used?

can be used in load-bearing areas

higher-resistance, low wear

what is a downside to conventional composites

polymerization shrinkage that can lead to stress on the tooth

where is bulk fil used

posterior teeth

what are the 2 types of bulk fil

conventional (higher resistance, low wear)

low-viscosity (not recommended for high stress areas)