COMPOSITE

COMPOSITION
● Resin ー chemical name = methyl acrylate (Denture base resin → PMMA)
● Filler ー glass fillers
● Coupling agent ー silane / organosilane*
● Packable and flowable composite difference
○ Viscosityーresistance to flow
● TEGMA is added to increase flow, ie becomes flowable composite
○ Eg: pit and fissure sealants.

FEATURES
● Micromechanical bonding
● Resin tags - penetrate into tooth structure -7 to 25 mm (tag length)
● Ratio of bonded : unbonded Molecules /components→ C factor
● Class I,II,III,IV → hybrid composite
● Class V ー microfilled composite
¤ High polishability
¤ ∴ maximum cleaning efficiency
¤ Or else rough surface → stains, calculus, perio problems etc.

TYPES OF COMPOSITES

MACROFILLED COMPOSITE
a. Average particle size ー 10 μm
b. 1st generation restoration composites.
c. Paste - paste , chemical cure
d. Limited shade matching capabilities
e. Poor physical and mechanical properties
f. Poor esthetics.

MICROFILLED COMPOSITE
g. Average particle size ー 0.04μm
h. Light cured
i. Suboptimal #toughness ー not strong for occlusal bearing area
j. Excellent esthetics and polishability
k. Lower elastic modulus ー better in class V
l. Use primarily in anterior restoration.

HYBRID (MINIFILL) COMPOSITE
m. Average particle size ー 1 μm
n. Light-cured
o. Good properties.
p. Good esthetics but not as polishable as microfilled.
q. Universal use ー anterior and posterior restoration.

MICROHYBRID COMPOSITES
r. Average particle size ー 0.4 to 0.8 μm
s. Light cured
t. Retain good properties of hybrid (strength) with improved handling.
u. Polishability almost equal to microfills
v. Universal use ー anterior and posterior.

NANOFILLED / NANOHYBRID COMPOSITES
w. Filler - 20 nm nanomers 0.6 to 1.5 μm nanoclusters
x. Light cured
y. Excellent handling
z. High polishability
aa. Low shrinkage
bb. Universal use ー anterior and posterior.

FLOWABLE COMPOSITES
cc. High matrix/filler ratio content
dd. Higher polymerization shrinkage

PACKABLE COMPOSITES
ee. Increased viscosity
ff. No documented benefits