direct-placement esthetic materials
tooth-colored materials that can be placed directly into the cavity preparation without being constructed outside of the mouth first
composite resin
tooth-colored materials composed of an organic resin matrix, inorganic filler particles, a coupling agent, and coloring pigments
organic resin matrix
thick liquids made up of two or more types of organic molecules (polymers) that form a matrix around filler particles
inorganic filler particles
fine particles of quartz, silica, or glass that give strength and wear resistance to the material
Silane coupling agent
a chemical that helps to bind the filler particles to the organic matrix
pigments
coloring agents that give composites their color
monomers
high molecular weight molecules with double carbon bonds that link to form polymers
self-cured composites
composites that polymerize by a chemical reaction when two filled resin pastes are mixed together
light-cured composites
single-paste composites that polymerize when a photosensitive chemical is activated by light in the blue wave range
dual-cured composites
composites that contain components of light-activated and chemically activated materials. When the two parts are mixed together, it polymerizes by a chemical reaction that can be accelerated by blue light activation
Macrofilled composites
an early generation of composites that contained filler particles ranging from 10 to 100 microns
Microfilled composites
composites that contain very small filler particles averaging 0.04 microns in diameter
hybrid composites
composites that contain both fine fill and microfill particles to obtain the strength of a macrofill and the polishability of a microfill
microhybrids
hybrid composites that contain fillers that are smaller fine-particle and microsized fillers
nanohybrids
microhybrids to which nanosized fillers have been added
universal composites
composites that have physical and mechanical properties such as strength and polishability that allow them to be used in both the anterior and posterior parts of the mouth
nanocomposites
composites that contain all nanosized fillers to enhance physical properties
flowable composites
light-cured, low-viscosity composite resins
bulk-fill components
composites with greater depth of cure that permit placement in large increments up to 4 mm thick instead of the standard 2 mm; their use speeds up the filling process
elastic modules
A measure of the stiffness of a material; the higher the elastic modules the stiffer the material
incremental placement
a technique for composites that places and cures small increments individually to reduce the overall polymerization shrinkage and shrinkage stress in the restoration
indirect-placement esthetic materials
tooth-colored materials that are used to construct restorations outside of the mouth in the dental laboratory or at chairside on replicas of the prepared teeth. They are later cemented to the teeth
glass ionomer cement (GICs)
self-cured, tooth-colored, fluoride-releasing restorative materials that bond to tooth structure without an additional bonding agent
hybrid (or resin-modified) glass ionomer
a glass ionomer to which resin has been added to improve its physical properties
nano-ionomers
glass ionomers that contain nanosized filler particles to enhance their physical properties
compomer
composite resin that has polyacid, fluoride-releasing groups added
the major components of composite dental materials include all of the following except one. Which one is the exception?
A. bonding agent
B. resin matrix
C. coupling agent
D. fillers
A. bonding agent
Composite resins are often classified according to their
A. strength
B. polishability
C. resin content
D. filler particle size
D. filler particle size
The shortcomings of flowable composites as compared with hybrid composites include all the following EXCEPT one. Which one is the EXCEPTION?
a. They are weaker
b. They wear faster
c. They shrink more when polymerized
d. They are more difficult to polish
d. They are more difficult to polish
The purpose of a silane coupling agent for composite resins is
a. to improve the bond between the filler and the resin matrix
b. to help the composite retain its color
c. to reduce the oxygen-inhibited layer
d. to help the various layers stick together
a. to improve the bond between the filler and the resin matrix
the curing light requires repair
a. it is causes a slower set of dark-color composite
b. if it has not been tested
c. if a 2mm thick piece if composite does not cure through the bottom at the recommended exposure time
d. if the light appears blue
c. if a 2mm thick piece if composite does not cure through the bottom at the recommended exposure time
the polymerization shrinkage of a composite
a. is cause for alarm
b. is greater than 10% of the volume
c. can be minimized by placing and curing a series of small increments
d. has no effect on the final restoration
c. can be minimized by placing and curing a series of small increments
fillers are composed of all of the following except one. which one is the exception?
a. quartz
b. alumia
c. silica
d. glass
b. alumia
which one of the following statements about a coupling agent is false?
a. it minimizes the loss of filler particles
b. it reduces wear
c. it prevents filler from sticking to the resin
d. it is made of silane
c. it prevents filler from sticking to the resin
fillers are composed of all of the following except one. which one is the exception?
a. quartz
b. alumia
c. silica
d. glass
...
all of the following will increase the wear of a composite restoration except one. Which one is this exception?
a. use of large filler particles
b. incompletely curing the composite
c. use of small amount of filler particles
d. saliva contamination of the
d. saliva contamination of the etched enamel
which one of the following types of composites is the weakest and should not be used in stress-bearing tooth surfaces?
a. hybrid
b. microfill
c. nanofill
d. nanohybrid
b. microfill
Heavily filling the resin matrix with nanosized fillers particles will reduce which one of the following?
a. curing time
b. strength of the material
c. the esthetics
d. polymerization shrinkage
d. polymerization shrinkage
which of the following composites attains a high shine when polished that lasts the longest?
a. hybrid
b. microhybrid
c. nanohybrid
d. nanocomposite
d. nanocomposite
which one of the following types of composites generally will shrink the most when polymerized?
a. bulk-fill composite
b. microhybrid
c. flowable composite
d. nanocomposite
c. flowable composite
common effects of polymerization shrinkage of composites may include all of the following except one. Which one is this exception?
a. microleakage
b. death of the pulp
c. microcracking of enamel causing white lines around the margins
d. postoperative sens
b. death of the pulp
Methods used to minimize polymerization shrinkage include all of the following except one. Which one is the exception?
a. cure the composite rapidly with a high intensity light
b. use prepolymerized filler clusters
c. use composite with a high filler cont
a. cure the composite rapidly with a high intensity light
all of the following circumstances may require a longer curing time for a composite except?
a. use of an opaque shade
b. use of increments of composite greater than 2mm
c. placement of the curing light tip 6 to 8 mm from the composite
d. composite placed
d. composite placed in a class III preparation on #8 mesial
What allows a new increment of composite to stick to the previously cured increment?
a. mechanical retention
b. chemical resin-to-resin bond
c. addition of a bonding agent to the cured increment
d. the silane coupling agent
b. chemical resin-to-resin bond
the function of the wedge placed interproximally with a class II preparation includes all of the following except?
a. stop bleeding
b. create slight separation of the teeth
c. seal the matrix band against the tooth at the gingival margin
d. protect the gi
a. stop bleeding
one of the advantages of glass ionomer compared to composite is
a. the ability to finish it immediately
b. that it has higher strength than composite because of the glass fillers
c. that it uses the same bonding agents as composites
d. that it has been sh
d. that it has been shown to release fluoride
which one of the following statements about glass ionomer cement (GIC) is false?
a. GIC chemically bonds to the mineral of the tooth
b. GIC releases fluoride
c. GIC functions well for class II restorations
d. GIC reduces microleakage at margins of a resto
c. GIC functions well for class II restorations
Hybrid (resin-modified) glass ionomers have all of the following advantages over conventional glass ionomers except one. Which one is this exception?
a. stronger
b. less sensitive to moisture when set
c. can be finished at the same appointment
d. contain
d. contain quartz fillers like some composites
Nano-ionomers have all of the following properties except one. Which one is this exception?
a. improved esthetics
b. increased wear resistance
c. improved polish
d. greater strength than nanocomposites
d. greater strength than nanocomposites
compomer restorative materials
a. release as much fluoride as glass ionomer materials
b. are only self-cure resins
c. are closer to composite resins in their makeup than to glass ionomer
d. are like glass ionomers in that they do not require a separate bo
c. are closer to composite resins in their makeup than to glass ionomer