materials composed of inorganic metal oxide compounds, including porcelain and similar ceramic materials that require baking at high temperature to fuse small particles together to form the restoration, or a pre-formed ceramic block from which the restora
ceramics
a tooth colored ceramic material composed of crystals of feldspar, alumina, and silica that are fused together at high temperatures to form a hard, uniform, glass like material
porcelain
restoration that has a metal core over which porcelain is fused at high temperature
porcelain-metal restoration
fusion of ceramic particles at their borders by heating them to the point that they just start to melt
sintering
ceramic restoration with no metal core
all-ceramic restoration
process whereby ceramic powder is mixed with a water based liquid to form a mass or slip. The slip is pressed into a form and baked at high temperature
slip-casting
pressing ceramic material into a mold at high temperature and pressure
heat-pressing
computer-assisted design/compter-assisted machining applies technology that uses computers to design and cut restorations from blocks of dental materials
CAD/CAM
thin layer of ceramic or composite resin material that is bonded to the fronts of teeth to improve their appearance
Veneer
the basic color of an object (e.g. red, yellow, green, blue)
hue
the intensity of the color
chroma
the brightness of a color or its lightness or darkness
value
porcelain restorations have
a. great stain resistance
b. low wear resistance
c. no disadvantages
d. easy reparability
a. great stain resistance
porcelain bonds to metal by which one of the following mechanisms?
a. micromechanical retention such as resin to etched enamel
b. penetrates the surface of the metal
c. fuses to oxides on the surface of the metal
d. shrinks when it is fired and locks itse
c. fuses to oxides on the surface of the metal
the main advantage of all-ceramic crowns over porcelain-bonded-to-metal crown is
a. their superior esthetics
b. their strength
c. their ease of cementation
d. the ease of taking shades
a. their superior esthetics
the main drawback of feldspathic porcelain for all-porcelain crowns is
a. their tendency to fracture
b. their opacity
c. the difficulty involved in making them
d. that shrinkage when fired makes them difficult to fit to the prepared tooth
a. their tendency to fracture
an in-office CAD/CAM system for ceramic restorations provides all of the following advantages EXCEPT one. which one?
a. the restoration does not have to be fabricated in an outside laboratory.
b. a provisional crown is not neede.
c. the procedure can be c
d. local anesthesia is not needed
the basic color of the tooth is called the
a. bashe shade
b. true value
c. chroma
d. hue
d. hue
all of the following should be avoided when taking the shade of a tooth EXCEPT one. which one?
a. lipstick on the patient.
b. brightly colored clothing
c. dirty teeth (covered with plaque)
d. neutral wall color in the room
d. neutral wall color in the room
all of the following materials should be avoided around ceramic restorations EXCEPT one. which one?
a. acidulated topical fluoride products
b. alginate impression material
c. coarse prophy paste
d. acid etchant
b. alginate impression material
the impression for a CAD/CAM crown is
a. done with alginate
b. done with polyvinylsiloxane impression material
c. done with polyether impression material
d. done by capturing an image of the prepared tooth with an optical scanner
d. done by capturing an image of the prepared tooth with an optical scanner
when preparing a porcelain-fused-to-metal crown, the technician applies feldpathic porcelain in layers to the metal coping. the inital layer is
a. translucent porcelain to mimic enamel
b. body porcelain to mimic dentin
c. opaque porcelain to hide the oxid
c. opaque porcelain to hide the oxidized metal
occasionally, special porcelain stains are used on the surface of the porcelain. these stains contain metal oxides and are used to
a. create a shiny, smooth surface
b. mimic white spots or fine crack lines to resemble adjacent teeth
c. hide flaws created
b. mimic white spots or fine crack lines to resemble adjacent teeth
which one of the following statements about porcelain veneers is false?
a. porcelain veneers are more durable than composite veneers.
b. porcelain veneer must be handled carefully when one is trying them in, bc they are very fragile until bonded to the to
d. porcelain veneers are usually cemented with zinc phosphate or glass ionomer cement
when assisting the dentist with taking the shade of a tooth, the dental assistant should
a. dry the teeth thoroughly
b. shine the operatory light directly on the teeth
c. cover brightly colored clothing with a pastel, neutral-colored bib
d. stare at the t
c. cover brightly colored clothing with a pastel, neutral-colored bib
when one is taking photographs of the teeth to send to the dental laboratory to help convey the correct shade, what is the proper location for the shade tab in the photograph?
a. outside of the mouth
b. inside the mouth and in front of the teeth
c. in the
c. in the same plane as the tooth being matched
a mixture of two or more metals
alloy
reaction that occurs when silver-based alloy is mixed with mercury
amalgamation
irregularly shaped particles formed by shaving fine particles from an alloy ingot
lathe-cut alloy
alloy particles produced as small spheres
spherical alloy
mixture of lathe-cut and spherical alloys
admixed alloy
a chemical reaction between tin in the silver-based alloy and mercury that causes corrosion in the amalgam
Gamma-2 Phase
oxidation affecting a thin layer of a metal at its surface. Not as destructive as corrosion
tarnish
oxidation from interaction of two dissimilar metals in the presence of a solution containing electrolytes (such as saliva). it results in breakdown of the amalgam
corrosion
gradual change in the shape of a restoration caused by compression from occlusion or adjacent teeth
creep
mechanical device used to mix the silver-based alloy particles with mercury to produce amalgam
triturator (amalgamator)
in the amalgam restoration, which of the following elements has the most effect on corrosion reduction?
a. silver (Ag)
b. mercury (Hg)
c. copper (Cu)
d. iron (Fe)
c. copper (Cu)
in the amalgam restoration, the two main components are
a. silver and copper
b. copper and tin
c. silver and mercury
d. mercury and zinc
c. silver and mercury
why should all remnants of amalgam be removed from the placement instruments before they are autoclaved?
a. the steam causes the amalgam to fuse to the stainless steel.
b. amalgam corrosion products produced by the steam are toxic.
c. the heat causes merc
c. the heat causes mercury vapor to be released from the amalgam
the strength of the amalgam restoration can be affected by
a. over- trituration
b. under-trituration
c. corrosion
d. all of the above
d. all of the above
a properly mixed amalgam should appear
a. dry and crumbly
b. soupy and shiny
c. as a homogeneous mass with a slight shine
d. liquid-like and should pour easily out of the capsule
c. as a homogeneous mass with a slight shine
scrap amalgam should be
a. autoclaved before it is sent to the recycler
b. thrown into the incinerator
c. stored under water in a sealed container
d. put into the general nonmedical waste
c. stored under water in a sealed container
with high-copper alloys, which metal reacts with copper to reduce gamma-2 phase corrosion?
a. tin
b. zinc
c. silver
d. lead
a. tin
the fact that mercury makes up almost half of the amalgam has caused concerns about
a. its safety for patient use
b. risks to the office staff
c. environmental effects of improper disposal of amalgam waste
d. all of the above
d. all of the above
amalgam has been popular for the restoration of carious teeth because
a. it is economical
b. it has excellent physical properties
c. it is easy to manipulate
d. all of the above
d. all of the above
bonding an amalgam during placement of a restoration
a. keeps it from corroding
b. prevents tarnish
c. seals the margins and reduces microleakage
d. increases postoperative sensitivity
c. seals the margins and reduces microleakage
how does tarnish differ from corrosion?
a. tarnish occurs only on the surface
b. tarnish is more harmful to the restoration than is corrosion
c. tarnish contributes to the destructive effects seen in the gamma-s phase.
d. tarnish cannot be removed by poli
a. tarnish occurs only on the surface
alloy containing at least 60% noble metals, 40% of which must be gold
high-noble alloy
alloy composed of non-noble metals. corrodes more readily
base-metal alloy
alloy composed of metals that do not corrode readily
noble alloy
classifcation of metal based on its high cost
precious metal
special casting alloys manufactured for their compatibility with porcelain that has been bonded to them at high temperature
porcelain bonding alloys
a think covering like a thimble that serves as a substructure for a porcelain-bonded-to-metal crown
coping
a process of heating porcelain at high temperature until it fuses
firing
a process whereby particles are heated to the point that they fuse together at their borders but do not clump into one solid mass
sintering
amt of stress at which a substance deforms
yield strength
firing porcelain at high temperature to achieve a smooth, shiny surface
glazing
an alloy used to join two metals together or to repair cast metal restorations
solder
an alloy that has been mechanically changed into another form to improve its properties
wrought metal alloy
to modify physical properties of a metal by heating it
anneal
an alloy of nickel and titanium often used for othodontic wires
Nitinol
a measure of the thickness of a wire/ the lower the gauge, the thicker the wire
gauge
a metal or nonmental dowel placed within the root canal to retain a core buildup
post
post that engages the root canal surface like a screw
active post
post that sits in the prepared canal space but does not actively engage the root surface
passive post
a post cast to fit precisely in the root canal space; usually has the core attached
custom post
factory-made post supplied in several sizes
pre-formed post
a gold alloy that is 50% gold has how many karats?
a. 24
b. 18
c. 14
d. 12
d. 12
the ADA recognized which 3 major categories of alloys?
a. high noble, noble, and low noble
b. high noble, noble, and base metal
c. precious, semiprecious, and nonprecious
d. class I, II and III
b. high noble, noble, and base metal
high noble metal classification must contain what percent by weight of gold?
a. 40%
b. 60%
c. 75%
d/ 90%
a. 40%
noble metal elements include all of the folowwing EXCEPT
a. silver
b. gold
c. palladium
d. platinum
a. silver
porcelain bonding alloys form oxides on their surfaces that chemically bong with the porcelain at high temperatures. which of the following metals may be added to the alloys to help form these oxides?
a. indium or tin
b. silver or copper
c. cobalt or chro
a. indium or tin
metal that is formed by casting into an ingot or bar and then is altered in its form by extruding or pressing it is known as
a. stainless steel
b. wrough metal
c. milled metal
d. transformed metal
b. wrought metal
high-noble alloys usually have which metals added to increase their strength?
a. silver or copper
b. nickel or beryllium
c. iron or aluminum
d. chromium or cobalt
a. silver or copper
which type of orthodontic wire is more difficult to adapt as an arch wire because of its springiness and tendency to maintain its original shape?
a. stainless steel
b. cobalt-chrome nickel
c. gold
d. nickel-titanium
d. nickel-titanium
allergy to nick
a. occurs in less than 3% of the population
b. is seen only in the oral cavity
c. occurs 10 times more often in women than in men
d. is associated more often with partial denture frameworks than with crowns
c. occurs 10 times more often in women than in men
solder has all of the following uses EXCEPT
a. adding a contact to a crown
b. joining a pontic to a bridge retainer
c. repairing a hole in the occlusal surface of a crown discovered at the periodic oral examination
d. joining a wire loop to a band to make
c. repairing a hole in the occlusal surface of a crown discovered at the periodic examination
the purpose of a flux used during soldering is to
a. lower the melting point of the solder
b. make the solder harden quickly
c. prevent the solder from flowing to areas where the solder is not needed
d. remove oxides from the surfaces of the metals to be
d. remove oxides from the surfaces of the metals to be soldered so the solder can flow and wet the surfaces better
pre-formed metal posts are available in all of the following materials EXCEPT
A. gold
b. stainless steel
c. titanium
d. titanium alloy
a. gold
the purpose of a post is to
a. strengthen the root
b. put a permanent seal over the root canal filling material
c. strengthen the core material
d. retain the core material
d. retain the core material
which one of the following statements about cast posts is false?
a. they are formed from a wax or acrylic resin pattern
b. they can be cast using high-noble, noble, or base-metal alloys
c. they usually have the core attached as part of the casting.
d. the
d. they are used in practice far more often than pre-formed posts
implant placed on top of the bone and under the periosteum
subperiosteal implant
implant that penetrates entirely through the bone
transosteal implant
implant placed into the bone
endosseous (endosteal) implant
metal cylinder placed into bone to support a crown or prosthesis
implant fixture
metal component that connects the implant crown to the implant fixture
implant abutment
component placed in the top of the implant fixture to prevent tissue from growing into the top of the fixture during healing
cover screw
replaces the cover screw when the top of the implant fixture is uncovered and it allows soft tissue to adapt to it
healing abutment
used in the implant impression to align the implant analog in the same way as the fixture was in the mouth
impression abutment
a replica of the implant fixture that is used in the laboratory fabrication of the implant crown
implant analog
the metal most commonly used in implants is
a. gold
b. silver
c. stainless steel
d. titanium
d. titanium
the type of implant that is instered into a hole drilled into the bone is
a. subperioteal
b. endosseous
c. transosteal
d. exosteal
b. endosseous
with a 2 stage implant, after the fixture is placed, which one of the following occurs?
a. implant crown is placed
b. the fixture is covered with bone.
c. a cover screw is placed and the fixture is voered by the soft tissue flap.
e. the healing abutment i
c. a cover screw is placed and the fixture is covered by the soft tissue
potential adverse outcomes when an implant fixture is surgically placed include
a. infection around the implant
b. perforation of one of the cortical plates of bone
c. improper angulation of the implant
d. damage to a nerve or a large blood vessel
e. all
e. all of the above
immediate placement implants are done
a. after the bone fills in the extraction socket
b. at the time of the extraction of the tooth that will be replaced.
c. only when a bone graft
d. to plug the hole made when the maxillary sinus is accidentally perfora
b. at the time of the extraction of the tooth that will be replaced
Implants can be used to support which of the following prostheses?
a. single crowns
b. fixed bridges
c. partial or complete dentures
d. all of the above
d. all of the above
Implant crowns are fixed to the implant fixture by which method?
a. welded on
b. cemented only
c. held in place with a screw only
d. cemented or held by a screw
d. cemented or held by a screw
The instruments used to clean implants where titanium is exposed include
a. carbon steel curettes
b. air polishers
c. ultrasonic tips
d. plastic curettes and scalers
d. plastic curettes and scalers
Which one of the following statements regarding the gingiva around an implant is false?
a. the gingiva has connective tissue fibers that connect or integrate with the surface of the implant.
b. When healthy, the gingiva produces a biological seal against
a. the gingiva has connective tissue fibers that connect or integrate with the surface of the implant.
The consequences of not maintaining good oral hygiene around an implant include all of the following EXCEPT one. which one?
a. inflammation and swelling of the gingiva
b. loss of the biological seal
c. bacterial invasion and potential loosening of the imp
d. increased bone growth due to chronic irritation
a procedure used to reduce excess restorative material to develop appropriate occlusion and contour; this is usually done with rotary cutting instruments.
Finishing
a procedure that produces a shiny, smooth surface by eliminating fine scratches, minor surface imperfections, and surface stains using mild abrasives frequently found in the form of pastes or compounds.
Polishing
a material composed of particles of sufficient hardness and sharpness to cut or scratch a softer material when drawn across its surface
abrasive
the particle size of the abrasive, typically classified as coarse, medium, fine, and superfine
grit
a procedure that is primarily meant to remove soft deposits from the surface of restorations and tooth structures.
cleansing
a procedure for removal of excessive restorative material from margins of restorations
margination
feather-like excesses of material present on occlusal and proximal surfaces
flash
excessive material present at the cervical cavosurface margin
overhang
the goal of finishing and polishing of restorations include
a. the removal of excess material
b. the smoothing of roughened surfaces
c. the production of better esthetics
d. all of the above
d. all of the above
cleansing of teeth is primarily meant to
a. remove excess material
b. smooth roughened surfaces
c. remove soft deposits
d. recontour surfaces
c..remove soft deposits
the depth and space between cuts made by an abrasive are determined by
a. the properties of the abrasive
b. the properties of the material being abraded
c. the contour of the restoration
d. both a and b
d. both a and b
which of the following represents the correct hardness ranking, from hardest to softest?
a. gold, amalgam, composite, enamel
b. enamel, amalgam, gold, composite
c. composite, enamel, gold, amalgam
d. amalgam, enamel, composite, gold
d. amalgam, enamel, composite, gold
all of the following will increase the rate of abrasion EXCEPT
a. increased pressure
b. decreased speed
c. use of larger abrasive particle
d. use of more abrasive particle than the substrate
b. decreased speed
Moh's scale ranks
a. materials by their relative abrasion resistance
b. hardness of a material
c. abrasiveness of a material
d. both a and b
c. both a and b
To control the numbers of abrasive particles that contact the surface,
a. the operator should increase the speed
b. the operator should decrease the pressure
c. the operator should use a lubricant
d. the operator should not use rotary instruments
c. the operator should use a lubricant
loose abrasives
a. are safe-sided
b. are used on cups and brushes
c. come in various shapes
d. use sterilizable mandrels
b. are used on cups and brushes
when performing an amalgam polishing procedure, which of the following can produce the most harmful biologic effect?
a. odor
b. heat
c. products of tarnish
d. airborne debris
d. airborne debris
the substance used to prevent a dentifrice from drying is called
a. humectant
b. binder
c. detergent
d. alkaline peroxide
a humectant