Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Restorative > Crown And Bridge > Flashcards

Crown And Bridge Flashcards

0
Q

What are the advantages of a 3/4?

A

More conservative than full gold crown or PFM
Assess the accuracy of marginal fit easily
Allows pulp testing from buccal cusp
Allows natural Appearnce of tooth to she

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
1
Q

When is a 3/4 gold crown indicated?

A

On a tooth where the lingual cusp has been lost and would compromised the remaining core if thr buccal cusp has to be prepared for a PFM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the disadvantages of 3/4?

A

Sides of crown can splay if heavy loads applied and stengh thing features not incorporated
Greater marginal area can lead to Increaed microleakage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the uses of 3/4 gold crown?

A

Heavily restored tooth with intact buccal cusp
Conventional bridge retainer
Tooth wear
Part of treatment plan for denture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What assessment would you do on the tooth before placing 3/4?

A

PROVE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How can the resistance and retention form of the 3/4 crown be improved?

A

Incorporate slots and grooves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the disadvantage of the slots and grooves?

A

Increase the complexity of cavity since must all be parallel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the stage of 3/4 gold crown prep?

A
  1. Occlusal reduction and Bevel
  2. Axial reduction
  3. Proximal surface groove and slot
  4. Occlusal grove
    5 finish
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How do you do the occlusal reduction 3/4?

A

Functional cusp: 1.5mm

Non : 1mm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the purpose of the reverse bevel 3/4?

A

Aka Functional cusp bevel

Brings cusp back in line, offers resistance to oblique forces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Which two bevels are placed on the 3/4 crown?

A

Functional and no function

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What type of finish is at the gingival margin of a 3/4?

A

Chamfer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How much is the axial reduction ?

A

0.7-1.0mm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What taper should the 3/4 hVe?

A

3-4 degrees

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Where do you place the slot on the 3/4 prep?

A

In the filling

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Where do you place the groove in the 3/4 ?

A

Not commonly

Placed in teeth that are heavily restored and subjected to tooth wear and placed into natures tooth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What does the occlusal grove help with in 3/4?

A

Resistance and strengthened the casting to cannot splay
Aids retention and resist crown dislodgement

Should be placed as far buccal as possible in Area of fissure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

When would you do the contemporary design for 3/4?

A

When cementing with super bond and panavia bit need to sand blast or oxidised fit surface of gold

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What does super bond have?

A

4 META

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are the indication for veneers?

A 
Alter the shaoe and size of tooth
Close diastema
Align mal aligned teeth
Mask areas of Hypoplasia and hypo calcification 
Mask dis coloured teeth
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the advantages of veneer over crown?

A

Less destruction
No LA
Easier to record impressions
No need to provisional restoration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are the disadvantages if a veneer over a crown!

A

More challenging to place a veneer on only one tooth and get good shade match
Try in is difficult
Luting is multistage and takes time to finish well
Poor prep can lead to porcelain fracture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

How much should you reduce the labial surface by on a veneer?

A

0.5mm

23
Q

What is the purpose of labial reduction on a veneer?

A

To avoid over contoured prep

24
Q

How many planes should you prepare the labial surface for a veneer in?

A

3
Gingival plane
Mid labial plane
Incisal plane

25
Q

Where can you place the gingival margin of the veneer?

A

Subginginval
Equigingival
Supra

26
Q

Where should the proximal margins be placed for a veneer?

A

Just Labial to contact point but can consider extending round the contact when veneer is used to close a diastema

27
Q

When would you bring the promxila preparation of a veneer interpromximal?

A

When recession present

Closing a diastema

28
Q

What are the options for the incisal edge of a veneer?

A

Over lapped
Overlap
But joint

29
Q

What are the advantages of restoring an edentulous ridge?

A 
Appearnce
Occlusal stability
Masticatory effeciency
Speech
Psychological
30
Q

What are the disadvantages of restoring an edentulous ridge?

A 
Damage to toot and pulp
Risk of Sedondary caries
Failures
Cost 
Periodontal effect
31
Q

What general factors about the patent do you need to consider before placing a bridge?

A

Attitude:
Age: young teeth have large pulps
Confidence: some patient lack confidence with dentre
Occupation: contact sport players do not give bridge, public speakers and singers give bridge and wind instruments too
Medical: epilipetics: consider fixed
appearance: high lip line, loss of tooth and bone an denture maybe better
OH: perio must be stabilised, bridge maybe better for perio
Disturbuton of missing teeth: multiple missing teeth consider denture
Occlusion: diffucult for denture in class 2/1

32
Q

What local factors do you need to consider before placing a bridge?

A

Adjacent teeth: sound or heavily restored, vital, tilted or rotated, bone support and perio
Oppsing dentitions: presence of over eruption,mapping of tooth wear, occlusal stops and crowding
Edentate ridge: degrees of resorption, condition of ridge, correct space for lost teeth

33
Q

What do you need for treatment planning?

A 
History
Mounted study models
Periaplcals
Bite wings
Pocket depth
Vitality
Crown and root ratio
34
Q

What are the options for provisional restorations?

A

Lab made

Chair side

35
Q

How are the chair side provisional restorations made?

A

Using higher acrylic (trim)

Mould of mouth or from study models and then make vacum formed PVC stent

36
Q

What are the three requirements for provisional restorations?

A

BAM
Biological
Aesthetic
Mechanical

37
Q

What should you use to cement the provisional?

A

ZnO eugenol

38
Q

What can you consider getting made before the final bridge?

A

Metal try in

Can try this and assess

  • seating
  • margin quality
  • occlusal stop
  • interference in occlusion
39
Q

What are the clinical problems if the bridge fails to seat?

A

Preparation errors: undercuts on teeth or not paralle
Impression error: incorrect tray
Temp errors: allowed over eruption, some Luting cement stillln prep

40
Q

What are the lab errors related to filling to seat?

A

Cast and die: porous or damage
Wax pattern : distorted, no separator, no reservoir
Investment: needs to compensate for setting expansion, hygroscopic expansion and thermal expansion
Casting: insufficient temp of investment and porosity of sprue, alloy too high temp

Finishing and polishing: trim margins, distorted since thing nodules on fit surface

41
Q

What can cause a rough fit surface of a lab made commonest?

A

Breakdown of investment or weak

Cracking of investment

42
Q

What do you do if bridge fails to seat?

A

Check fit surface for imperfections

Check contacts for over contoured
Section metal frames work through Pontic
Re unite with duraly and recheck in mouth

43
Q

What can you consider doing once you happy with with final bridge and before cementation?

A

Can consider temp cementing it using ZOE with 50% modifier paste

This enables minor tooth movements
Patient can inspect the crown
Adjust any occlusal interferences

44
Q

Why are bridges sometimes difficult to seat?

A

Hinge hydrostatic pressure due to large surface area and paralle

45
Q

What should you check on the bridge?

A

Margins
Occlusion
Gingival health
Mechanical integrity

46
Q

How many bridges failed after 15 years?

A

33%

47
Q

How many bridges failed after 10 years?

A

<5% abutment extracted

48
Q

Wheh should a provisional bridge be made?

A

Before the impression of the bridge prep to enable checking that you have reduced the teeth enough

49
Q

Why may provisional bridges be placed long term?

A

Ppfollwing pre prosthetic surgery

Assess healing of endo or perio

50
Q

What are the biological requirements of a provisional restorations?

A

Biocompatible
Non exothermic
Stabilise tooth position eg prevention of over eruption or tilting

51
Q

What are the mechanical requirement of a provisional restoration?

A

Attain rubbery stage quick
Rapid hardening
Suffering strength to resist wear and fracture
Strong in thin sections

52
Q

What are the aesthetic requirements of a provisional restoration?

A

Tooth coured
Range of shades
Surface texture and staining possible.

53
Q

What are the resins available for provisional restorations?

A

Acrylic: powder and liquid. Powder PMMA beads + peri oxide. Liquid is MM monomer +activator

Higher meathcrykate trim: powder and liqueurs. Powder: PMM beads + peri oxide, liquid: isobutylmethacrylate + activator

Epimine eg Scutan: paste and liquid p. Paste: imine pre polymer + poly amide filler and liquid : soul phonic acid ester

Composte eg protemp: 2 pastes methacrylic acid ester + filler

54
Q

How does the lab made the provisional restoration ?

A

Minimal deoth th prep and the heat cured acrylic resin by lost wax technique an then relines at chair side using trim

Ad: custom shape of retainer and Pontic, good strength, can be used for long term

Dis: cost and must be made in advance if tooth prep

55
Q

How can you make provisional restorations chair side?

A

Using Higher acrylic and take a mould from the mouth using ROD of waxed study model then fill PVC stent with matersl

Ad: cheaper, made on same day as abutment prep, strong enough to last until final bridge,clinician can check if sufficiently reduces the prep
Dis: limited customising of Pontic and retainer

Restorative (45 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions