Endodontic Principles Flashcards

1
Q

A patient presents with pain from the upper right quadratnt. Tooth 17 has a cavity, and the patient tells you a white filling fell out recently. The tooth has a normal periradicular appearence, and pain only occurs when the patient eats sweets.

Give a provisional diagnosis, and describe you management of the case.

Pain history: Lasting less than 10 minutes and is difficult to localise.

A

Reversable pulpitis

Dress the exposed dentine with a restoration.
Follow up in 1-2 weeks to see if pain has resolved.
If resolved, monitor for three months then annually.

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

Two periapical radiographs show lower anteriors 42, 41, 31, 32 that have all been treated endodontically with posts and cores. There are radiolucencies in all of the teeth affected. The patient is referred to you for periradicular surgery.

Name three alternative treatment options to periradicular surgery.

A

Orthograde re-treatment
Extraction
Monitor the teeth if asymptomatic

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

Two periapical radiographs show lower anteriors 42, 41, 31, 32 that have all been treated endodontically with posts and cores. There are radiolucencies in all of the teeth affected. The patient is referred to you for periradicular surgery.

List six things you would discuss with the patient to achieve valid consent.

A
  1. Give all the other options available.
  2. The risks and benefits of the treatment options.
  3. The likely long term prognosis of the teeth in both cases.
  4. What may happen if no treatment is carried out.
  5. The costs that are involved for treatment.
  6. Your professional opinion on what should be done.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Two periapical radiographs show lower anteriors 42, 41, 31, 32 that have all been treated endodontically with posts and cores. There are radiolucencies in all of the teeth affected. The patient is referred to you for periradicular surgery.

What are the risks and benefits of periradicular surgery?

A

Risks:
- Infection
- Swelling and discomfort
- Nerve damage
- Root fracture

Benefits:
- Preservation of the tooth
- Elimination of infection
- Improved overall prognosis

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

Two periapical radiographs show lower anteriors 42, 41, 31, 32 that have all been treated endodontically with posts and cores. There are radiolucencies in all of the teeth affected. The patient is referred to you for periradicular surgery.

Which factors dictate the long term success of peri-radicular surgery, and what is the average prognosis for the treatment?

A

Success of the surgery
Patient compliance (OH etc.)
Tooth condition
Patient factors (MH, overal health, etc.)

Average success for releaving symptoms is 85% to 95%.
Around 80% of teeth last longer than 4 years.

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

Two periapical radiographs show lower anteriors 42, 41, 31, 32 that have all been treated endodontically with posts and cores. There are radiolucencies in all of the teeth affected. The patient is referred to you for periradicular surgery.

What are the indications for peri-radicular surgery?

A

When orthograde root canal treatment cannot be completed due to persistent exudation into the root canal

If symptomatic or progressing periradicular disease associated with a well root-filled tooth.

When a biopsy of periradicular tissue is required.

When visualisation of the periradicular tissues and tooth root is required if perforation or root fracture is suspected.

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

Two periapical radiographs show lower anteriors 42, 41, 31, 32 that have all been treated endodontically with posts and cores. There are radiolucencies in all of the teeth affected. The patient is referred to you for periradicular surgery.

What are the contraindications for peri-radicular surgery?

A

The primary disease has not been stabilised
The coronal seal is poor
The tooth is unrestorable
Suspected diagnosis of a combined periodontal–endodontic lesion
The prognosis of the tooth is limited
There is a root fracture

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

Susan is a 29 year old patient who is a regular attendee at your practice, she has previously undergone periodontal treatment, she attends as an emergency complaining of pain in her upper front tooth. On examination you notice a swelling pertaining to the 11, TTP and there is associated lymphadenopathy.

Give 2 differential diagnoses for what this condition could be.

A

Periodontal/periapical abscess
Periapical granuloma

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

Susan is a 29 year old patient who is a regular attendee at your practice, she has previously undergone periodontal treatment, she attends as an emergency complaining of pain in her upper front tooth. On examination you notice a swelling pertaining to the 11, TTP and there is associated lymphadenopathy.

Give two special tests you could perform to confirm a diagnosis.

A

Sensibility test with EPT/EC. If non vital would indicate periapical abscess, if vital then a periodontal abscess.

Periapical radiograph of the 11, would identify if there was a periapical radiolucency, indicating abscess location.

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

Susan is a 29 year old patient who is a regular attendee at your practice, she has previously undergone periodontal treatment, she attends as an emergency complaining of pain in her upper front tooth. On examination you notice a swelling pertaining to the 11, TTP and there is associated lymphadenopathy.

Give two ways you could establish drainage of the swelling.

A

Soft tissue incision and irrigation with CHX/Saline.
Extripation of pulp and encourge draining through canal.
Extraction of the tooth also possible if indicated.

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

Susan is a 29 year old patient who is a regular attendee at your practice, she has previously undergone periodontal treatment, she attends as an emergency complaining of pain in her upper front tooth. On examination you notice a swelling pertaining to the 11, TTP and there is associated lymphadenopathy.

Outline your inital management of the patient if the 11 was not endodontically involved.

A

Incision and drainage of abscess

Gentle subgingival debridement, short of base to prevent trauma and infection spreading

HSMW

OHI

Pain relief

Anti-biotics - PenV: 250mg, 2 tablets, four times daily

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

A 49 year old woman has been seeing you for a root treatment of 16. The root canal system has been fully prepped, incuding the mesiopalatal canal. She is attending a third appointment with the aim of obturating the canal.

What three criteria must be met before obturation is carried out?

A

Tooth must be asymptomatic
Canal must be fully dried
There must be full biomechanical cleaning on all canals.

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

A 49 year old woman has been seeing you for a root treatment of 16. The root canal system has been fully prepped, incuding the mesiopalatal canal. She is attending a third appointment with the aim of obturating the canal.

The canal is obturated using gutta percha cones via cold lateral compaction. Name three constituents of the cones other than the GP.

A

Zinc Oxide 65%
Radiopacifiers 10%
Plasticisers 5%

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

A 49 year old woman has been seeing you for a root treatment of 16. The root canal system has been fully prepped, incuding the mesiopalatal canal. She is attending a third appointment with the aim of obturating the canal.

Describe the function of root sealer when placing GP cones.

A

To seal surface between dentinal walls and cone.
To fill voids and irregularities/lateral canals.
To lubricate during obturation for better cone fit.

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

A 49 year old woman has been seeing you for a root treatment of 16. The root canal system has been fully prepped, incuding the mesiopalatal canal. She is attending a third appointment with the aim of obturating the canal.

Give three types of sealer commonly used for obturation.

A

Calcium hydroxide (dycal)
Epoxy resin sealer (AH26 plus)
Bioceramic sealer (Calciul silicate/phosphate)
ZOE
RMGI

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

A 49 year old woman has been seeing you for a root treatment of 16. The root canal system has been fully prepped, incuding the mesiopalatal canal. She is attending a third appointment with the aim of obturating the canal.

Describe how you can assess an obturation on a radiograph.

A

Correct legnth
Correct taper
Density is consistent, and no voids
All canals filled with sealer and GP
No sealer/GP above orifice.

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

A 49 year old woman has been seeing you for a root treatment of 16. The root canal system has been fully prepped, incuding the mesiopalatal canal. She is attending a third appointment with the aim of obturating the canal.

What is the purpose of obturation?

A

To seal the remaining bacteria in
To provide apical/coronal seal (mircoleakage)
To prevent reinfection

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

A 49 year old woman has been seeing you for a root treatment of 16. The root canal system has been fully prepped, incuding the mesiopalatal canal. She is attending a third appointment with the aim of obturating the canal.

Give four methods for obturation.

A

Cold lateral compaction
Warm verical compaction
Continuous wave compaction
Carrier based obturation (thermafil)

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

Describe and explain the faults and mishapes that can occur when preparing a canal with a stainless steel file.

A

Ledges - occurs when working short of the length and are difficult to bypass

Canal blockage - caused by dentine debris getting packed into the apical portion of the root and attempted to remove this can result in false canal being cut and possible perforation

Apical zipping/transportation of the foramen -occurs as a result of the tendency of the instrument to straighten inside a curved canal and ultimately results in a teardrop shape canal.

Perforations/broken file - too much pressure put when using the instruments or binding of k-files.

20
Q

Describe the endodontic process including calculating working length until the obturation stage.

A
  1. Pre-op radiograph to identify canals and get estimated working legnth - assess tooth for long term prognosis and restorability.
  2. Remove all caries and defective restorations from the crown
  3. Coronal access to the root canal system using rubber dam and LA
  4. Root canal system instrumentation and preparation and irrigation with
    Sodium hypochlorite using either rotary or hand instruments.
  5. Irrigation should be performed throughout, alternating between EDTA and hypochlorite.
  6. Corrected working legnth established with endo file radiograph, or apex locator.
  7. Canal shaped to provide a continuous taper down to apex, with the prep stopping 1-2mm before the apex.
  8. Canal should be dried, and prep checked before obturation.
21
Q

Susan is a 29 year old patient who is a regular attendee at your practice, she has previously undergone periodontal treatment, she attends as an emergency complaining of pain in her upper front tooth. On examination you notice a swelling pertaining to the 11, TTP and there is associated lymphadenopathy.

Upon further investigation, a 10mm probing depth can be found on the palatal side of the tooth. What is your diagnosis and how would you manage this?

A

Periodontal abscess
Infection of existing pocket due to trauma/build up of bacteria.

Drainage via incision or via pocket with instrumentation to dilate
Gentle sub gingival debridement
Hot saline mouthwash use or 0.2% CHX mouthwash
Antibiotic use if there is systemic involvement
Follow up with HPT

22
Q

A patient attends with pain coming from his 15. Upon investigation you find it is root treated, and has a 9mm pocket distal to the tooth, and a vertical bone defect.

Give three differential diagnosis for tooth 15.

A

Perio-endo lesion
Endo-perio lesion
True combined lesion

23
Q

A patient attends with pain coming from his 15. Upon investigation you find it is root treated, and has a 9mm pocket distal to the tooth, and a vertical bone defect.

List two special investigations you could carry out.

A

6 point pocket chart of the area
Periapical radiographs

24
Q

A patient attends with pain coming from his 15. Upon investigation you find it is root treated, and has a 9mm pocket distal to the tooth, and a vertical bone defect.
What inital treatment would you carry out?

A

Re-root treatment, then monitor to see if symptoms resolve.

25
Q

A patient attends with pain coming from his 15. Upon investigation you find it is root treated, and has a 9mm pocket distal to the tooth, and a vertical bone defect.

You attempt to re-root treat the tooth, but this fails and the tooth is extracted. What options are there to replace the missing tooth?

A

RPD
Bridge
Implant

26
Q

A patient attends with pain coming from his 15. Upon investigation you find it is root treated, and has a 9mm pocket distal to the tooth, and a vertical bone defect.

You attempt to re-root treat the tooth, but this fails and the tooth is extracted. The patient asks for an implant to replace the tooth, what factors would impact whether an implant is suitible?

A

Local factors:
- Bone quality and quantitiy
- OH
- Space between the implant and adjactent teeth

General factors:
- Smoking status
- Periodontal status
- Medical history (osteoporosis, bisphosphonate use, immune health)

27
Q

A patient attends with pain coming from his 15. Upon investigation you find it is root treated, and has a 9mm pocket distal to the tooth, and a vertical bone defect.

You attempt to re-root treat the tooth, but this fails and the tooth is extracted. The patient asks for an implant to replace the tooth, what interventions can be done to increase bone levels in the area?

A

Guided tissue regeneration
Bone grafting
Biological mediators
Sinus lift

28
Q

What percentage of maxillary first 1st molars have a MB2 canal?

A

93% have four canals, 7% have three canals.

29
Q

What are the three deisgn objectives for preping a root canal for obturation?

A

Create a continuously taping funnel shape
Maintain apical foramen in its origional position
Keep apical opening as small as possible, do not enlarge apex

30
Q

What are the advantages of using a crown down technique?

A

Removes bulk of infected tissue, allowing for irrigent resevoir

Keeps reference point for working legnth the same

Makes straight line access easier

Limits spread of infected material at apical foramen

31
Q

What is the avergae life span of a well perfomred endodontic treatment?

A

10-15 years, though some last longer.

32
Q

What are the three laws of pulpal floor anatomy?

A

Law of colour – always darkened

Law of symmetry 1 – orifices lie equidistant from MD line through chamber

Law of symmetry 2 – orifices lie perpendicular on MD line

Note: Symmetry laws do not apply to maxillary molars.

33
Q

What are the three rules for locating orifices in the pulpal floor?

A

They are always:
- At the junction of the floor and walls
- At an angle between floor and wall
- At the terminus of developmental fusion lines

34
Q

List four reasons for irrigation during endodontic root canal preparation.

A

Disinfection of canals
Dissolve and flush out organic debris
Lubricate canal for instruments
Remove endodontic smear layer

35
Q

Why is 3% sodium hypochlorite a good irrigant?

A

It is a potent anti-microbial
It disolves pulp remains and collagen
It disolves both vital and non-vital tissue
Helps disrupt the smear layer

36
Q

Name another common irrigant used other than hypochlorite and EDTA.

A

Chlorhexidine digluconate

37
Q

How is the endodontic smear layer removed?

A

EDTA is a chelating agent, capable of removing the smear layer when combined with hypochlorite.

17% EDTA and 3% hypochlorite is used for a 1 minute contact time.

This opens the dentinal tubules and allows sealer/irrigent penetration.

38
Q

Give two intra-canal medicimants and state their use.

A

Anti-microbial paste - reduces inflamation and facilitate follow up treatment.

Non-setting calcium hydroxide - antimicrobial activity, reduces inflamation, and removes tissue debris.

39
Q

Give three reasons for instrumentation of root canals.

A

To remove infected soft/hard tissues
To give irrigants access to apical space
Create space for delivery of medicimants/obturation
Reatin integrity of radicular structures

40
Q

Outline the use of protaper files for canal preparation.

A

Size 10/15 K files taken to working legnth.
S1 file for coronal third of crown.
S2 file for middle third of crown.
Size 10/15 K files for corrected working legnth.
F1 file for apical third prep.

41
Q

What advantage do protaper files have over K-files?

A

Shape memory
Super elasticity
Decrease lateral pressure to avoid ledges
Decreased number of instruments needed
Increased cutting efficiency
Easier to use

42
Q

Name two rotary endodontic systems.

A

Reciproc
ProTaper Gold

43
Q

What are the four motions you can use with endodontic files?

A

Filing
Reaming
Watch winding
Balanced force

44
Q

Name four reasons why an endodontic file may break?

A

Flexural stress (from cyclic fatigue)
Torsional stress (binding to canal wall)
Complicated/surved canal or non-straight line access.

45
Q

What are five complications of using stainless steel files in a 20 degree curved canal?

A

Ledges
Blockages
Zipping
Perforations
Fractured instruments