pretty lecture lady Flashcards
most used restorative material (direct or indirect restorations)
composite resins
3 resin matrix
bis-GMA
UDMA
TEGDMA
high molecular weight???
bis-gma
increase the mechanical and physical property
filler particles (reinforcement of resin matrix
in composites, monomers to be coverted into:
this process is triggered by:
polymers
free radicals
classification of composites:
- filler particle size and size distribution (hybrid and nano*)
- handling characteristics
- type of polymerization
classification by handling characteristic :
1
2
3
- regular (many applications; versatile, layering tech., more esthetic
- flowable (better flowability and adaptation, polymerization shrinkage, under regular comp. class II)
- bulk fill
developed to enable restoration in single increment built up to 4-5mm
bulk fill composite
characteristics of bulk fill composites
- increased depth of cure (polymerization)
- reduce polymerization shrinkage stress
- improved adaptation to the surface of the cavity
- simplified placement tech.
~~~~how do bulk fill composites achieve these characteristics?
- modulating the polymerization reaction= relieving shrinkage stress
- depth of cure (polymerization)
- flowability and adaptation to the surfaces of the cavity
bulk filler composites filler particles:
-lower amount of filler particles
-pre-polymerized filler particles
-low elastic modulus= help absorb stresses
-added larger filler size particles
what kind of monomers do bulk filler composites used
- UDMA
-modified UDMA (adding aromatic groups)
-fragmentation dimethacrylate monomers
bulk fill composites use what type of monomers??
(typical polymerization of methacrylate)
-fragmentation monomers(stress relieving monomers)
bulk fill composites also utilized alternative photoinit
bulk fill composites can be categorized into two categories/types
- flowable bulk fill
- full body bulk fill
this category of bulk fill composite has lower elastic modulus and reduced wear resistance
-base for regular composites as the occlusal increment
-dent replacement only
-better adaptation on the surfaces of the cavity
flowable bulk fill
this category of bulk fill composite has
with bulk fill flow, leave how much space to add regular composite towards occlusal?
~2mm
this type of bulk fill has rheological modifiers that react to the sonic energy applied during placement (sonic vibration=becomes flowable composite)
sonic activated bulk flow
what does the sonic application do
reduce viscosity =
this bulk flow system
essential steps for esthetic appearance (match with the surrounding tooth structure) and functionality
finishing and polishing
polished and finishing decreases the coefficient of friction which
reduced the rate of wear
advantages of bulk fill composite
-simple
-less chair time
-better flowability
-***reduced polymerization and shrinkage
disadvantages of bulk fill
-more translucent that regular
-indicated for posterior restorations
-cannot mimic natural layering of tooth
acid-base, self-adhesive materials, combining fluro-aluminosilicate glass powder and polyacrylic
basic composition of powder (glass)