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Flashcards in 7. ACC II Deck (69)
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1
Q

Indications for cubic zirconia

A
  • Anterior and PM crowns

- Anterior and PM bridges with one pontic

2
Q

Minimal thickness for cubic zirconia

A

1.2 mm

3
Q

Differences between regular zirconia and more translucent zirconia

A

More translucent zirconia

  • Requires more reduction
  • Gentler handling during chairside adjustments (esp posterior restorations)
  • Use with caution in molar region
4
Q

Esthetics for translucent zirconia (are/aren’t) consistent

A

aren’t- longevity of the stain??

5
Q

Describe inlays and onlays

A

Inlay
-Intracoronal restpration made outside the tooth

Onlay
-Restoration with one or more cusps and adjoining occlusal surfaces or the entire occlusal surface and is retained with mechanical or adhesive means

6
Q

Indications for inlays/onlays

A
  • High esthetic demand
  • Good OH and low caries rate
  • Durable alternative to posterior resin and amalgam restorations
  • Esthetic alternative to gold inlays and onlays
  • When optimal contours can’t be achieved with direct restorations
7
Q

Advantages of inlays/onlays

A
  • More wear resistant (direct rest.)
  • Conservative prep (FCC)
  • Less marginal leakage (resin)
  • Enhanced contours (resin)
8
Q

Why might inlays/onlays have less polymerization shrinkage compared to resin

A

Leakage is related to polymerization shrinkage and high CTE

-Thin layer of resin is used to lute inlay/onlay –> less shrinkage

9
Q

Rank the following in order of most to least tooth reduction (with thier percentages)

  • Onlay
  • MO inlay
  • ACC
  • MOD Inlay
  • PFM crown
A

PFM (76%)>ACC(72%)>Onlay(39%)>MOD inlay(27%)>MO inlay(20%)

10
Q

Contraindications for inlays and onlays

A
  • Patients with high caries risk

- Patients with parafunctional habits

11
Q

Onlay retention comes from

A

Bonding rement cement/adhesion

12
Q

T/F E.max and Empress are indicated in bruxers

A

f- Zr is

13
Q

Can you use Zr for inlay/onlay? Why/ why not

A

No because the bond is not as durable with resin cement because Zr has no glass phase

14
Q

Disadvantages of inlays/onlays

A
  • Accurate occlusion can be hard
  • Areas of occlusal adjustment need careful finishing and polishing (time consuming- rough porcelain is abrasive against the opposing arch
  • Wear of composite resin luting agent –> marginal gaps
  • Finishing of margins can be hard in interproximal regions due to access –> perio disease
15
Q

Occlusal adjustments for inlays and onlays are made (before/after) cementation

A

after

16
Q

Marginal gaps

A

100 nm

17
Q

What determines the general outline of the prep for an inlay/onlay

A

caries

18
Q

Interproximal margin of inlay/onlay is done with what bur

A

shoulder

19
Q

Min. dimension for occlusal reduction for onlay prep should be

A

1.5 mm

20
Q

Min dimension for the width of the gingival floor for onlay and inlay

A

1-1.5 mm

21
Q

Min width of inlay isthmus prep

A

1 mm

22
Q

Min isthmus depth for inlay

A

1 mm

23
Q

Onlay prep with axial reduction is commonly done for what reason

A

overcome poor blending of restoration to facial surface

24
Q

Ideal prep for onlay is _ occlusal reduction with the cavosurface margin between what thirds of the tooth

A

1.5-2mm…. incisal and middle thirds

25
Q

Margins should be _degrees at the butt joint of an inlay and why

A

90… bevels are contraindicated

26
Q

Margins for pnlay are done with what bur and why

A

deep chamfer because you want a obtuse angle (>90 degrees at the but joint) to remove unsupported enamel prisms

27
Q

Before prepping the tooth for inlay/onlay what should you do and why

A

-Mark the occlusal contacts with articulating paper

Done to ensure no margins are on occlusal contacts and help restore normal occlusion

28
Q

Margins on inlays and onlays should be (supra/sub-) gingival

A

supra

29
Q

Need POI- therefore need to eliminate undercuts- what materials can block them out

A

RMGI or resin

30
Q

Proximal clearance should be at least _ mm to allow for what

A

0.6 mm to allow clearance of impression material

31
Q

What is used to make the temporary restoration for an inlay/onlay

A

-Telio CB Inlay (formerly called fermit)

32
Q

Is telio CB inlay light cured

A

yes

33
Q

Telio CB inlay is also used to

A

cover implant screw abutments

34
Q

What should be given to the patient after placing a temp with telio CB inlay

A

superfloss (locks in interproximals for retention)

35
Q

The axial walls in an MOD cavity prepared for a cast gold onlay should angles (diverge/converge) from the (gingival/proximal) walls to the (pulpal/axial) walls

A

converge…. gingival… pulpal

36
Q

For all inlays and onlays the internal walls taper from (external to internal or internal to external) and all external walls (converge/diverge)

A

internal to external… converge (this prevents undercutes)

37
Q

Advantages of porcelain laminate veneers

A
  • Conservative

- No anesthesia needed

38
Q

Indications for porcelain laminate veneers

A
  • Discolored, pitted, fractured anteriors

- **multiple discolored but otherwise sound teeth

39
Q

Concern with porcelain laminate veneers

A
  • Inadequate reduction –> over-bulked (perio health)
  • Must be bonded to enamel
  • Optimal isolation needed
  • Knowledge and experience in shade alteration
40
Q

What are the three (4) veneer preps and which are the most and least conservative

A

-(nor prep veneer) more conservative> Traditional > Extended > Full

41
Q

Describe the differences in veneer prep designs

A

Traditional

  • Proximal contact is preserved
  • Most conservative

Extended
-Additional overlap (more insical reduction

Full

  • Proximal contacts are removed
  • Long overlap (most incisal reduction)
42
Q

The preferred design for porcelain laminate veneers (does/doesn’t) maintain part of the insical edge in enamel ….what happens if this is not possible

A

does … if not possible a modified prep with a lingual extension is needed

43
Q

Give the ideal reductions for a conventional prep for the gingival, middle and insical thirds of the tooth

A
Gingival= 0.3 mm 
Middle= 0.5 mm 
Insical= 0.7 mm
44
Q

Overbulking of veneers can lead affect (fricative/sibilant) sounds

A

fricative

45
Q

Minimum thickness of a lithium disilicate press veneer is at the gingival margin aspect (thinnest part of veneer)

A

0.3mm

46
Q

Describe the thickness of enamel for anterior teeth in the gingival, middle, and insical thirds

A
Gingival= 0.3mm 
Middle= 0.5 mm 
Insical= 1mm
47
Q

There are two types of depth cutting burs than can be used for veneers- which is recommended

A

0.3 mm (verses the 0.5 mm)

48
Q

If you want to increase the insical edge with the veneer what must you include in your prep

A

Insical reduction and lingual finishline

49
Q

What must you do in order to achieve equal reduction

A

stick to existing plane of tooth

50
Q

How many planes are on the facial surface of incisors

A

3

51
Q

Veneer margins must be on

A

enamel

52
Q

what if the tooth you want to veneer has a class III filling

A

Extend the prep to include the restoration

**veneers are contraindicated in teeth with extensive restorations

53
Q

What materials can you use for veneer provisionals

A
  • Integrity

- Flowable

54
Q

How do you cement the provisionals with veneers

A

spot etch technique (no retention form in prep)

55
Q

Zirconia (is/isn’t) a glass ceramic

A

isn’t

56
Q

What materials are used to make veneers

A
  • Feldspathic porcelain (not commonly used anymore)
  • Empress (leucite)
  • E.max
57
Q

What are glass ceramics

A

made of a glassy (silica) and a crystalline phase

58
Q

What veneers and crowns are the most esthetic

A

empress

59
Q

Which is preferred and why empress or E.max

A

e.max due to increased strength and more conservative prep

60
Q

Which has higher flexural strength (CAD/Pressed) E.max

A

pressed

61
Q

Cubic zirconia is (weaker/stronger) than E.max

A

stronger

62
Q

With is indicated for 3 unit bridge not extending past the PM region (pressed/CAD) LD

A

both

63
Q

Connector size for 3 unit Emax bridge

A

16mm2

64
Q

Connector size for tetragonal zirconia bridge

A

9-12 mm2

65
Q

Connector size for cubic zirconia bridge

A

16mm2

66
Q

T/F Cubic zirconia bridge can be any size and any location

A

F- true for tetragonal but cubic is limited to 3 unit not extending into molar region

67
Q

What restorative materials require adhesive bonding and which can be bonded either adhesively or conventionally

A

Need adhesive

  • Feldspathic
  • Leucite

Either

  • Emax (CAD and Pressed)
  • Tetragonal and cubic zirconia
68
Q

What restorative materials require selection of natural die (or stump) shade

A

Yes

  • Leucite
  • E.max (both kinds)

No
-Tetragonal Zirconia

Not sure
-Cubic zirconia

69
Q

Which restorative materials require try in paste

A

Yes

  • Leucite
  • E.max (both kinds)

No
-Tetragonal Zirconia

Not sure
-Cubic zirconia