final sg Flashcards
you want to make a CEREC crown for #31. which block would be best choice to mill the restoration from given its physical properties?
Sirona zirconia
A metal ceramic preparation on a mx incisor prepared with a path of insertion too lingual will have:
- monoplane facial reduction
- higher potential for pulp exposure
- thin incisal edge
what is NOT a provisional material?
lithium disilicate
typical thickness of opaque porcelain:
0.1-0.2 mm
you are staining a #8 PFM. hue is correct but chroma and value are high. What color (s) shoudl you use?
violet
for an all ceramic crown prep, the shoulder finish line should terminate
NOT 1 mm facial or lingual to or at proximal contact
After preparing a post space in distal root of 30 for size yellow post you notice that the post is not stable in BL or MD direction. the prep is 8 mm from readiographic apex and movemtn transcribes and arc of 3 mm, canal is straight what to do?>
increase post length by 2mm
a shade sample that matches under the operatory light, but not in natural daylight is an example of:
metamerism
what is not an acceptable finsish line for an all ceramic crown?
shoulder bevel
in the CEREC crown project, the mx antagonist image was occluded with the mn prep image using:
buccal scan
which of the following is the most common mode of post and core failure:
post loosening
the process of re-emission of radiant energy at a lower frequemcies htan it is absorbed is called:
fluorescence
sirona blocks come in the following translucencies:
opaque (O)
medium (M)
translucent (T)
which block is made of composite resin
paradigm MZ100
what cannot be directly milled with CEREC
PFM
when do you glaze a CEREC crown
- extrinsic colarant is desired
2. the restoration is milled from lithium disilicate
resin-bonded bridges shoudl be prepped in enamel to optimize bonding
auxiliary retention features such as grooves and rests are not required
T, F
the vita lumin shade guide has better coverage of the shade range of natural teeth than the vita 3D master shade guide
vita lumin is organize din 4 different lightness gorups (ABCD)
F, F
best tool to move a cusp to achieve tripodized oclusal contact on CEREC computer is
shape/anatomic/4 directional
human tooth shades are located primarily in which quadrant of the CIELAB color space?
+a, +b
which metal is most resistant to developing an oxidation layer for a given firing cycle
high noble
what i smost likely cause of as ignle poistive bubble on your die
poor syringe technique
in a doubel chored im pression technique a thinner cord is first inserted in the sulcus followed by a thicker cord on teh top: the top core is then removed and impression is made
T, T
the buccal path of insertion for a PFM crown for 8 as prepared in lab is
- tangential to facial HoC
2. halfway between the emrgence profile and the incisal 1/3
main benefit of using lentulo spiral is deliver of a void free fill of luting agent int o canal
it is importatn to run spriral in reverse
T, F
when shade selecting, squinting wil l help in seeing the VALUE of the teeth BECAUSE it restricts amoutn of ight enter eye and activated more rod cells which are photopic
T, reason F
post most resistant to fracture
custom cast post (AgPd)
which area of tooth typically has the lowest value
incisal 1/3
3 is endo treated and anticipated to have 2 remaining cusp walls after preparing. the foundation restoration of choice is…
pre-fabricated post and core
finest color of rupper wheen/point in dialite porcelain polishing system
gray
coarset rubber wheel/point in dialite porcelain polishing system
blue
medium rubber wheel in dialite porcelain polishing systerm
pink
when selecting lights for your offic, which of hte follwoing would you be interested in
CRI
color temperature
excessive incisal reduction of an all ceramic crown can result in
- inc risk post-prep sensitivity
- inc risk porcelain fracture
- decresased resistance form
size 0 cord is
purple/white
000 cord
black/white
00 cord
black/yellow
1 cord
blue/white
2 cord
green/white
3 cord
red/white
when placing grooves in d of 9 and mesial of 11 of a resin-bonded bridge preparation from 9-11, the grooves shoudl be
just lingual to widest mesiodistal portion
OmniCam requires NO powdering of natural teeth
T
bis acryl should first be expressed from mixing tip
onto bracket paper
biocopy feature of CEREC best employed for
a zirconia crown replacing a partial denture abutment
zirconia is a ____ ceramic
polycrystallin
alumina, lithium disilicate and leucite are __ ceramci
particle filled glass
CEREC blocks used to fabricate your lower first molar crown in the lab are fabricate dfomr which type of ceramic
feldspathic (porcelain)
phase of zirconia gives it its favorable physical properties for dentistry
tetragonal
which of folowwing can be used a dopant to stabilize zirconia
- Y2O
- CaO
- MgO
monolithic zirconia crowns will be ____ the final sintered crown
larger than
the prp for a monolithic zirconia crown most closely resembles the prep o f
Full gold crown
which type of provisional material cna be spot bonde dfor temporizaiton of veneer prps
bis acryl
what is NOT a bis acryl provisional material
duralay
best cement for luting porcelain veneers is
resin cement
bis acryl is easier to add to than duralay
bisacryl does not generate as much heat during polymerization
F, T
yello;brown precipitate occuring using astringident in presnec e of blod from what element
Fe
which of hte folowing msut be cemented with resin cmeent
- resin bonded bridge
2. porcelain veneer
CEREC system cna be used for both chair side and laboratory generated restorations
T
which steps may require impression cord be placed
- preparation
- provisionalization
- impression
best color for resting eyes during shade selection
gray
which shade guide has lowest coverage error
vita 3D master
when you look at shade of tooth, color you see is due to ____ color mixing
subtractive
IPS empress (leucite reinforced ceramic) is etched iwth HF for 20 sed e max (lithium disilicate) is ethec for 60 sec
F, F
IPS = 60 s
emax = 20 s
zirconia = sand blast only
monobond plus is a
silane coupling agent
parapost drills from smallest to largest
brown, yellow, blue, red
paraposts WITHOUT rounded head design
XP
