Brainscape's Knowledge GenomeTM

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


See full index

BDS4 Restorative > Restoration of Endodontically treated tooth > Flashcards

Restoration of Endodontically treated tooth Flashcards

1
Q

What should be considered when assessing endodontically treated tooth clinically?

A

Coronal seal - restoration type
-> Leakage/Caries?

Amount of remaining tooth structure- ferrule

Is the tooth restorable?

Can you isolate it with rubber dam?

Swelling

Sinus

TTP- indicates if inflammation in PDL

Buccal sulcus - tender to palpation

Mobility

Increased pocketing – periodontal disease and root fractures

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

What is the sign of vertical root fracture?

A

Long/narrow pocket not reflected in other areas of mouth

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

What are we looking for on radiographic assessment of endodontically treated tooth?

A

Root filling - length, quality of obturation (voids)

Unfilled/missed root canals

Shape of canal

Patency - fracture instruments, posts, sclerosis

Bone support – mild, moderate, severe

Crown to root ratio (1:1.5)

Pathology - periapical radiolucency (healing?), resorption, perforations

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

How doe external root resorption appear in endodontically treated teeth?

A

Lack of conical apex

Moth eaten appearance

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

What are some of the issues when doing reRCT?

A

Lack of remaining tooth structure- ext/int

Lack of/no ferrule

Wide post holes

Endodontic complications - fractured instruments, perforations, short/long root fillings

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

How much do certain cavities weaken tooth by?

A

MOD cavity- weakens tooth by 66 %
MO cavity- weaken by 33%

If you cut an access cavity- it takes away large proportion of structural integrity

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

What is coronal microleakage?

A

Ingress of oral micro-organisms into the root canal system
-> one of main causes of RCT failure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What can be done to prevent coronal microleakage?

A

Root filled teeth unrestored for 3 months or longer should generally be re-root canal treated

Trim GP to the AC and place RMGI over pulp floor and root canal openings

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

Why is cusp coverage required for endodontically treated teeth in posterior region?

A
  • Prevent coronal microleakage
  • Prevent catastrophic fracture (tooth splits though furcation or breaks underneath alveolar crest)

** RCT must be adequate- disinfected with NaOCl and obturated accurately

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

What are some of the myths regarding the properties of endodontically treated teeth?

A

More brittle

Prone to fracture

Not as hard

Dehydration affects hardness

-> evidence against all of these claims

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

What are the treatment options for endodontically treated anterior tooth with intact marginal ridges?

A

Composite restoration- if small B/L access cavity

Veneer (not protective)

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

What are the treatment options for endodontically treated anterior tooth with intact marginal ridges but discoloured crown?

A

Bleaching

Veneer

Crown

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

What are the treatment options for endodontically treated anterior tooth with destroyed marginal ridges?

A

Core build up with crown

Post crown

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

What is required for direct posts?

A

Ferrule

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

What is the post option if there is no ferrule?

A

Cast post and cores (not fibre)
-> avoid if possible and build up core with composite

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

What is the purpose of a post core?

A

Gains intraradicular support for a definitive restoration
-> Core provides retention for crown
-> Post retains the core (placed in root canal)

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

What are the issues with post core crowns?

A

Posts do not strengthen or reinforce teeth

Preparation of the root canal for a post, weakens the tooth

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

Why may a diaphragm be added to a post?

A

To provide bulk in root that has fractured

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

In what teeth should posts be avoided?

A

Mandibular incisors- too narrow/tapering roots

Premolar- in maxillary 4s, 75% have 2 canals
-> tapering roots
-> small pulp chambers
-> proximal invaginations

Curved canals- perforation risk

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

If a post must be put in a molar tooth, where is it best placed?

A

 Put in longest, straightest canal
 Lower molar- distal root
 Upper- palatal root

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

What are the guidelines for post placement?

A

4-5mm root filling apically- maintains apical seal

Post width
-> No more than 1/3 of root width at narrowest point and 1 mm of remaining circumferential coronal dentine

Sufficient alveolar bone support, at least half of post length into the root

Minimum 1:1 post length/crown length ratio

Ferrule
-> At least 1.5mm height and width of remaining coronal dentine

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

What is a ferrule?

A

Encirclement of 1- 2 mm of vertical axial tooth structure within walls of a crown

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the function of a ferrule?

A

Braces crown at neck of tooth- helps prevent fracture, rotational movement and leakage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What can be done if no ferrule is present?

A

Orthodontic extrusion or CLS can be considered (if no other options and meticulous OH)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are the options for a tooth with ferrule that is hollowed out significantly?

A
  • Fibre post
  • Composite
  • Cast post (is this conservative?)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

How is a post cemented?

A

Using GI or resin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Where should a crown prep finish ideally?

A

Ideally crown prep finishes on tooth tissue (not always possible)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What are the ADV/DIS of DT light posts?

A

ADV
- Are meant to change colour when contact moisture- easier visualisation
- Flexes the same as dentine

DIS
- need enough tooth structure and ferrule
- Difficult to take out as they are bonded in with composite
- Moisture and technique sensitive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What are the features of the ideal post?

A

Parallel sided
- Avoids ‘wedging’
- More retentive than tapered

Non-threaded (Passive)
-> Smooth surface incorporates less stress to remaining tooth than threaded (Active)

Cement Retained
-> Less retentive than threaded posts but cement acts as buffer between masticatory forces and post/tooth

30
Q

What are the different types of prefabricated post?

A

Tapered Smooth
Tapered Serrated
Tapered Threaded
Parallel Smooth
Parallel Serrated
Parallel Threaded

31
Q

What are the ADV/DIS of prefabricated posts?

A

ADV
Only 1 visit required
No impressions and laboratory visit required
Chairside core build-up- immediate preparation of core
Large selection of designs and materials

DIS
Post and core are different materials

32
Q

What is the main issue with tapered post?

A

Wedges on tooth and flexes on biting

33
Q

What are the different types of metal post?

A

cast gold, stainless steel, brass, titanium

34
Q

What are the ADV/DIS of metal post?

A

ADV:
Radiopaque

DIS:
Poor aesthetics
Root fracture
Corrosion
Nickel sensitivity

35
Q

What are the different types of ceramic post?

A

Alumina

Zirconia

36
Q

What are the ADV/DIS of ceramic posts?

A

ADV
High flexural strength
High fracture toughness
Favourable aesthetics

DIS
Difficult retrievability
Root fracture is common

37
Q

What are the different types of fibre post?

A

glass, quartz, carbon

38
Q

What are the ADV/DIS of fibre posts?

A

ADV
Flexible- similar properties to dentine
Aesthetic
Retrievable
Bond to dentine with DBA’s

DIS
Radiolucent on radiographs

39
Q

What are the ADV/DIS/recommended uses/precautions for tapered pre-fab posts?

A

ADV:
Conservative
High stiffness
High Strength

DIS:
Less retentive

RU:
Small circular canals

Precautions:
Avoid excessively flared canals

40
Q

What are the ADV/DIS/recommended uses/precautions for parallel prefab posts?

A

ADV:
High strength
Good retention

DIS:
Expensive
Corrosion if SS
Less conservative

RU:
Smaller circular canals

Precautions:
Exercise care during prep

41
Q

What are the ADV/DIS/recommended uses/precautions for threaded posts?

A

ADV:
High retention

DIS:
Stresses created can cause fracture

RU:
When max retention is essential

P:
Avoid fracture during seating

42
Q

What are the ADV/DIS/recommended uses/precautions for Custom cast post and core?

A

ADV:
Higher strength than prefab

DIS:
Less stiff
Multiple appointments
Technically complex

RU:
Elliptical or flared canals

P:
Remove nodules before insertion

43
Q

What is a core build up?

A

Internal part of tooth is built-up with restorative material to replace the lost tooth tissue
-> core is prepared- provides retention and resistance for definitive restorations

44
Q

What are the ADV/DIS of composite cores?

A

ADV:
* Tooth coloured- better aesthetics
* Bonds to tooth
* Immediate prep
* On demand set

DIS
* Technique sensitive- moisture control required

45
Q

What posts is a composite core used with?

A

FIBRE

46
Q

What are the drawbacks of Amalgam cores?

A
  • Retention required
  • Poor aesthetics
  • Must wait a day until you prepare it
  • Avoid pinned amalgams
47
Q

What is the issue with GIC core?

A

Absorbs water and core expands in size

48
Q

What is the aim of a core build up?

A

Make it look like ideal crown prep of unrestored tooth
-> 6 degree taper
-> 2mm occlusal clearance

49
Q

What is a nayaar core?

A

Traditionally uses amalgam
 Utilises pulp space and some of the root canal system for more retention
 Difficult to retreat
 Composite can be used- difficult as no colour contrast

50
Q

What is the main advantage or restoring eddo-treated tooth with onlay?

A

more conservative, removes less tooth structure

51
Q

How is cusp fracture avoided when placing onlay?

A

Want it to go over cusps
-> ensure cusp has been reduced by 2mm as it will fracture if not

52
Q

What are the materials for onlays?

A

Bell glass- pressed composite
Zirconia
Gold

53
Q

What is an endo crown?

A

Indirect version of Nayyar core
 Increases surface area for bonding and part in pulp space will give mechanical retention
 Difficult to keep dry
 Mostly zirconia

54
Q

What is paracore?

A

Core material which is similar to bulk fill flowable composite

55
Q

What are the features of Smart Dentine Replacement?

A
  • Self-settling properties
  • Shade is not great
  • Etch tooth, bond and inject
  • Stronger than traditional flowable
56
Q

What are some principles to keep in mind when restoring/retreating endodontically treated teeth?

A

 Do not rush obturation- will take longer to fix it
 Spend time on disinfection too (especially if you are putting post in it)
 If you are concerned about quality of current RCT, then re-do
 Posts are last resort- structural integrity is really poor

57
Q

What are the steps in restorative cycle?

A

Small filling
Large filling
RCT
Crown
Post crown
ReRCT / re post crown
Extraction

-> Aim to stop advancing

58
Q

What can be used to ascertain whether GP plug is still present when placing a post?

A
  • Loupes
  • Microscope
  • Radiographs- to check seal
59
Q

What can be used to remove posts?

A

Ultrasonic
Trephan- Masseran
Eggler device
Moskito Forceps (screw retained)
Sliding hammer
Anthogyr (Safe relax)

60
Q

What are the features of ultrasonic tips for post removal?

A

Can be made of SS with diamond/Titanium
-> Remove very small bits of dentine

61
Q

What are the features of the masseran trephan?

A

Cores around post
 Can be destructive
 Can be combined with ultrasonic

62
Q

What are the problems with post removal?

A

You can’t remove it
Root fracture (immediate or delayed)
Render tooth unrestorable
Post space too wide
You break post

63
Q

What are the issues that can occur when carrying out treatment involving posts?

A

Perforation

Core fracture

Root fracture or crack

Post fracture

64
Q

What can be done to mitigate perforation?

A

Use Reciproc motor (electric motor) with post drill- 1000rpm at torque 4 gives more control

65
Q

What are the treatment options for post perforation?

A

Repair
-> Internal
-> External- periradicular surgery, restore with MTA

Extraction

66
Q

What are the reasons for post failure?

A

60% due to Restorative reasons (secondary caries, unrestorable tooth etc)

32% due to Periodontal problems

8% due to Endodontic reasons

67
Q

What can be used as a provisional for a post crown?

A

Provisional post core crown ( Temp bond)

Immediate denture

Dressing- Not aesthetic but might prevent leakage

Essex retainer

68
Q

What are the components of the para post system?

A

Provisional post

Burn out post (not important)

Para post drill

Impression post

69
Q

What is written in the lab prescription for parapost?

A

Please construct cast post and core.

Para post (colour)

Core 6 degree taper

Please leave 2mm space in occlusion for Crown

Enclosed registration / opposing impression

Shade

70
Q

What are the steps in the try-in of a parapost?

A

Check post space for temp bond

Irrigate chlorhexidine 0.2%

Dry paper points

Ensure fits around prep

Do you have enough occlusal clearance

71
Q

What are the steps in the fit of a post?

A

Be careful not to fill post space with cement
-> You may prevent it seating

Use firm apical pressure

Get rid of excess

Can ask lab for provisional acrylic crown

Make sure no excess around when taking crown impression / fitting MCC

Practice fit sequence

BDS4 Restorative (12 decks)

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