Endodontics Flashcards

1
Q

What are the methods of periodic-endo communications?

A

Perforations
Root apex
Lateral canals
Fractures
Dentinal tubules

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

What are the ideal properties of an obturation material?

A

Biocompatible
Dimensionally stable
Unaffected by oral fluid
Insoluble
Radiopaque

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

What is the composition of gutta percha?

A

20% GP
60% Zinc Oxide
10% Radiopacifiers
5% Plasticisers

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

What is the function of a sealer?

A

Seals space between dentine wall and core
Fills voids and irregularities
Lubricates obturation

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

What are the ideal properties of a sealer?

A

Good adhesion
Easily mixed
Bacteriostatic
Insoluble
Radiopaque
No shrinkage
Slow set

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

How does zinc oxide eugenol perform as a sealer?

A

Antimicrobial
Free eugenol can be toxic

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

How does glass ionomer perfom as a sealer?

A

Bonds dentine
Difficult to remove
Minmal antimicrobial

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

How does resin perform as a sealer?

A

Good sealer
Good slow
Slow set 8 hours

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

How does calcium silicate perform as a sealer?

A

High pH (12.8)
Biocompatible
Good seal

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

What are the 9 endo laws?

A

Centrality
Concentricity
ACJ
Symmetry 1
Symmetry 2
Colour
Orifice Location 1
Orifice Location 2
Orifice Location 3

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

What is the law of centrality?

A

Floor of pulp is central to the tooth at the ACJ

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

What is the law of concentricity?

A

Walls of pulp chamber are concentric to the external surfaces at the ACJ

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

What is the law of the ACJ?

A

The ACJ is the most consistent, repeatable landmark for locating the pulp chamber

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

What is the Symmetry Law 1?

A

Orifices of canal are equidistant from line drawn in mesio-distal direction through the pulp chamber floor

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

What is the exception to the symmetry 1 law?

A

Upper 6’s

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

What is the symmetry law 2?

A

Orifices of canal lie on perpendicular to a line drawn in a mesio-distal direction across the centre of the pulp chamber

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

What is the exception to symmetry law 2?

A

Upper 6’s

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

What is the colour law?

A

Colour of pulp chamber floor is darker than the walls

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

What is the orifice location 1 law?

A

Orifices are located at junction of walls and floor

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

What is the orifice location 2 law?

A

Orifices are located at angles in the floor wall junction

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

What is the orifice location 3 law?

A

Orifices are located at terminus of root development fusion lines

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

How can endodontic equipment be classified?

A

Manually operated
Low speed
Engine driven NiTi rotary
Engine driven adapts to canal
Engine driven reciproc
Ultrasonic

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

How can endodontic equipment be classified?

A

Manually operated
Low speed
Engine driven NiTi rotary
Engine driven adapts to canal
Engine driven reciproc
Ultrasonic

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

What is Nitinol?

A

Equiatomic alloy of nickel and titanium

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

What are the special features of nitinol?

A

Exotic material: does not conform to typical rules of mettalurgy
Superelasticity: application of stress does not result in usual proportional strength

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is the crystal structure of NiTI?

A

Temperature dependent structures of martensite and austenite:
Martensite= soft and ductile
Austenite= strong and hard

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

What is shape memory?

A

Material deformed at one temp then returns to original shape

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

What are the components of rotary instruments?

A

Taper
Flute ; groove to collect dentine and soft tissue
Cutting edge
Land; surface between flutes
Relief; reduction in land
Helix angle; angle formed by cutting axis and long axis of files

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

What is the purpose of irritants?

A

Remove debris
Lubricate
Dissolve organic and inorganic material
Penetrate to canal periphery
Kill bacteria/yeast
Disrupt biofilm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What does sodium hypochlorite ionise in water to form?

A

Na+ and OCl-

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is the effect of pH on sodium hypochlorite?

A

Acid/neutral: HOCl predominates
>9; OCl- predominates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What are the ideal features of obturation materials?

A

Easily manipulated
Seals canal laterally and apically
Unaffected by moisture/fluid
Sterile
Dimensionally stable
Non-irritant
Radiopaque
Easily removed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What are the ideal properties of sealers?

A

Tackiness
Easily mixed
Bacteriostatic
Insoluble in tissue fluids
Radiopacity
No shrink on set
Slow set

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What is gutta percha?

A

Transiosomer of poly-isoprene

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What are the design objectives

A

Continuously tapering funnel
Maintain apical foramen position
Apical opening as small as possible

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What are the clinical objectives?

A

Remove infected hard and soft tissue
Prevent re infection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What is endodontic success improved by?

A

Hypochlorite irrigation
Dental dam

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Why is dental dam used in endodontic?

A

Protects airway
Improves access
Improves efficacy and vision
Prevents contamination
Protects soft tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What are the pulpal diagnoses?

A

Normal
Reversible Pulpitis
Symptomatic Irreversible Pulpitis
Asymptomatic Irreversible Pulpitis
Pulp Necrosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

How does a normal pulp present?

A

Asymptomatic
Normal thermal response
Vital

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

How does symptomatic irreversible Pulpitis present?

A

Lingering pain to stimulus
Pain with postural change (night)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

How does reversible Pulpitis present?

A

Inflamed
Pain to stimulus
Resolves with treatment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

How does asymptomatic irreversible Pulpitis present?

A

No symptoms
Normal response to thermal tests

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

How does pulp necrosis present?

A

Negative pulp test
TTP
Radiographic osseous breakdown
May be asymptomatic

45
Q

What are the apical diagnoses ?

A

Normal
Symptomatic apical periodontitis
Asymptomatic apical periodontitis
Acute apical abscess
Chronic apical abscess
Condensing osteitis

46
Q

How does a normal apical diagnosis present?

A

Not TTP
Uniform PDL space

47
Q

How does symptomatic apical periodontitis present?

A

TTP
Pain on biting
Periapical radiolucency

48
Q

How does asymptomatic apical periodontitis present?

A

Asymptomatic
Periapical raidolucency

49
Q

How does an acute apical abscess present?

A

Rapid
Swelling
TTP
Spontaneous pain
Systemic problems

50
Q

How does a chronic apical abscess present?

A

Gradual
Asymptomatic
Periapicla radiolucency
Sinus (with or without pus)

51
Q

How does condensing osteitis present?

A

Localised bony reaction to low grade inflammatory stimulus
Diffuse Periapical radiopacity

52
Q

What are the aims of mechanical preparation?

A

Creates space to allow irritants and medicaments to more effectively eliminate micro-organisms
Remove infected hard and soft tissue

53
Q

What are the stages of mechanical preparation?

A

Tooth preparation
Access cavity
Confirm straight line access
Initial negotiation, coronal flaring
Working length determination
Apical preparation

54
Q

What are examples of irritants?

A

3% NaOCl
17% EDTA
0.2% CHX

55
Q

What are the lengths of times for the final irrigation?

A

10 minutes NaOCl
1 minute EDTA
10 minutes NaOCl

56
Q

What are the ideal properties of irritants?

A

Disinfect canal (remove micro-organisms)
Dissolve organic and inorganic material
Remove smear layer
Cheap
Non-toxic to Periapical tissues

57
Q

What are the pros of sodium hypochlorite?

A

Dissolves organic material
Disrupts smear layer
Effective antimicrobial

58
Q

What are the cons of sodium hypochlorite?

A

Doesn’t remove smear layer
Dissolves fabrics
Risk of hypochlorite accident

59
Q

How are sodium hypochlorite accidents managed?

A

Copious irrigation
Analgesia
Review

60
Q

What can be done to prevent a hypochlorite accident?

A

Bib/eyewash
Slow flow rate (1ml/15s)
Depress with index finger
Don’t lock needle in canal
Use a side vented Leur-lock 27G needle
Avoid excessive pressure

61
Q

What is the smear layer?

A

Superficial (1-5um) layer of organic pulpal and inorganic dentinal material formed during prep
Prevents disinfection and sealer penetration

62
Q

What can be used to remove the smear layer?

A

17% EDTA
10% citric acid
MTAD

63
Q

What is an example of an intra-canal medicament?

A

Non-setting calcium hydroxide

64
Q

What are the features of calcium hydroxide?

A

Antibacterial
Reduces inflammation
Kills mirco-organisms
Removes tissue debris

65
Q

What are the purposes of chemomechanical prep?

A

Irrigate to remove microbes
Remove smear layer
Prepare shape for obturation to WL
Flush out debris
Allows delivery of irritants

66
Q

What is estimated working length?

A

Estimated length at which instrumentation should be limited
1mm short of radiographic apex

67
Q

What is estimated working length?

A

Estimated length at which instrumentation should be limited
1mm short of radiographic apex

68
Q

What is corrected working length?

A

Actual length at which instrumentation should be limited

69
Q

What is the master apical file?

A

Largest file taken to working length
Represents final prepared size of apical canal

70
Q

What are the ideal properties of irritants?

A

Low cost
Reduction of friction
Temperature control
Good penetration within the root canal system
Killing of platonic microbes
Non-toxic to Periapical tissue
Doesn’t react with dental materials or weaken dentine
Washing action
Improve cutting of dentine by instrumentation
Dissolution of organic and inorganic
Killing of biofilm
Non allergenic

71
Q

What is the optimum concentration of sodium hypochlorite?

A

0.5-6%

72
Q

What percentage of sodium hypochlorite is used in GDH?

A

3%

73
Q

How thick is the smear layer?

A

1-5um

74
Q

What is the protocol for removing the smear layer?

A

3% NaOCl - 10 mins
17% EDTA- 1 min
3% NaOCL- final rinse

75
Q

What is the cause of external infection related inflammatory root resorption?

A

Root resorption caused by PDL damage
Root canal toxin reaching external root surface causing resorption
Tooth is non-vital

76
Q

What is vertucci type 1?

A

Single canal

77
Q

What is vertucci type 2?

A

2-1
Two canals that join into one

78
Q

What is vertucci type 3?

A

One canal that divides into two then merges into one
1-2-1

79
Q

What is vertucci type 4?

A

Two separate canals
2

80
Q

What is vertucci type 5?

A

One canal that separates into two
1-2

81
Q

What is vertucci type 6?

A

Two canals that join then separate into two
2-1-2

82
Q

What is vertucci type 7?

A

One canal leaves the pulp chamber, divides, rejoins and divides at the apex
1-2-1-2

83
Q

What is vertucci type 8?

A

Three separate distinct canals
3

84
Q

What are the benefits of nickel titanium files?

A

Superelasticity

85
Q

What are the benefits of coronal flaring?

A

Reduces hydrostatic pressure
Reservoir for irrigants

86
Q

What are the pulpal diagnoses?

A

Healthy Pulp
Reversible Pulpitis
Symptomatic Irreversible Pulpitis
Asymptomatic Irreversible Pulpitis
Necrotic Pulp
Previously treated

87
Q

What is the management of reversible pulpitis?

A

Pulp therapy

88
Q

What is the management of irreversible pulpitis?

A

Pulpotomy
Pulpectomy
Extraction

89
Q

What is the management of necrotic pulp in a mature tooth?

A

RCT
Extract

90
Q

What is the management of necrotic pulp in an immature tooth?

A

Pulpotomy
Pulpectomy
Extract

91
Q

What are the periapical diagnosis’?

A

Normal
Asymptomatic Periapical Periodontitis
Symptomatic Periapical Periodontitis
Acute Apical Abscess
Chronic Apical Abscess
Condensing Osteitis

92
Q

How does asymptomatic periapical periodontitis present?

A

No pain
Radiolucency

93
Q

How does symptomatic periapical periodontitis present?

A

Pain on biting
Percussion
Palpation

94
Q

How does acute apical abscess present?

A

Rapid onset
Spontaneous pain
Swelling

95
Q

How does chronic apical abscess present?

A

Slow onset
Little/no discomfort

96
Q

How does condensing osteitis?

A

Bony reaction to low grade inflammatory stimulus

97
Q

How does reversible present?

A

Pain to cold (short lasting)
Hydrodynamic expression (microleakage)
No change in pulp blood flow

98
Q

How does irreversible present?

A

Spontaneous pain
Sleep disturbance
Negative to cold
Pain to heat (c fibres)
Increased pulpal blood flow

99
Q

How do non-vital teeth present?

A

Discoloured
Sinus
Gross caries
Large restoration
Radiographic (periapical radiolucency)

100
Q

What is the aim of sensibility tests?

A

To test neuron/nerve function
Very subjective

101
Q

What are examples of sensibility tests?

A

EPT
Thermal tests
Test drilling

102
Q

What are the features of calcium hydroxide?

A

Bacteriocidal/Bacteriostatic
Highly alkaline pH 12.5; stimulates dentine formation
Stimulates pulpal cells to recalcify demineralised dentine
Neutralised acidic restorative material

103
Q

What are the features of mineral trioxide aggregate?

A

High pH
Creates bacterial tight seal
Can act as a base for restorative material

104
Q

What are the components of mineral trioxide aggregate?

A

Portland Cement (75%)
Bismouth Oxide (20%
Gypsum (5%)

105
Q

What are the two types of MTA?

A

White
Grey (includes iron)

106
Q

What are the disadvanatages of calcium hydroxide?

A

Weak cement
Very soluble if not protected

107
Q

What are the disadvantages of mineral trioxide aggregate?

A

Prolonged set time
Discolouration

108
Q
A