Endodontics 4 - Session 1

Question 1

Describe the aetiology of endodontic disease (3)

Answer 1

1. Bacterial invasion
2. Development of a bacterial ecosystem
3. Biofilm formation

Question 2

What are the design objectives when carrying out a RCT?

Answer 2

1. Create a continuously tapering funnel shape
2. Maintain apical foramen in original position
3. Keep apical opening as small as possible

Question 3

Describe the 5 steps involved in carrying out a full RCT

Answer 3

1. Coronal access to the root canal system
2. Root canal instrumentation and preparation
3. Obturation of the root canal system
   - sealing of RCS to prevent multiplication of bacteria
4. Coronal seal
   - prevents ingress of bacteria from the oral cavity back into the RCS
5. Final restoration

Question 4

What type of radiograph needs to be taken and what must be in view to diagnose whether or not a RCT is necessary?

Answer 4

1. Periapical radiograph
2. Must be undistorted
   - all of the root must be in view
   - 2-3mm of surrounding peri-radicular tissue must be in view

Question 5

List 6 things to look for in a radiograph that could affect your prognosis around a RCT

Answer 5

1. Peri-radicular pathology + how far does it extend
2. The anatomy of the root canal system
3. Canal calcifications
4. Angulation of root in relation to adjacent teeth
5. Number, length and morphology of roots
6. Proximity of vital structures

Question 6

What must be done before carrying out any RCT on a tooth?

Answer 6

All caries and defective restorations must be removed

Question 7

Where is the ideal access location for an RCT on a maxillary anterior tooth?

Answer 7

Middle 3rd of the crown, triangular cavity with apex towards the pulp

Question 8

What are the objectives of access cavity preparation?

Answer 8

1. Remove entire roof allowing complete removal of pulpal tissue
2. Allow visualisation of root canal entrance
3. Produce smooth walled preparation with no overhangs
4. Allow unimpeded straight-line access of instruments