Restoration of the Endodontically Treated Tooth 1

Question 1

How do we assess RCT of a tooth? (2)

Answer 1

1. Clinical assessment

2. Radiographic

Question 2

What does a clinical assessment for an RCT include? (3)

Answer 2

1. Coronal seal
   - Restorations
   - Crowns
   - Leakage
   - Caries
2. Amount of remaining tooth structure
   - Is there enough to make a ferrule (dentine collar) to make a crown on
3. Is the tooth restorable?
   - Can we isolate with rubber dam

Question 3

List some clinical signs of endodontic infection (6)

Answer 3

1. Swelling
2. Sinus
3. TTP
4. Buccal sulcus
   - Tender to palpation
5. Mobility
6. Increased pocketing
   - Perio diseae + root fractures

Question 4

What does a radiographic assessment of an RCT include? (7)

Answer 4

1. Root filling
   - Length
   - Quality of obturation e.g. voids
2. Unfilled/missed root canals
3. Shape of canal
4. Patency
   - Fracture instruments
   - Posts
   - Sclerosis
5. Bone support
   - Mild
   - Moderate
   - Severe
6. Crown to root ratio
7. Pathology
   - Periapical radiolucency
   - Healing
   - Resorption
   - Perforations

Question 5

What is coronal microleakage

Answer 5

Ingress of oral micro-organisms into the RC system

- Most important cause of RC failure

Question 6

What are some problems post RCT/re-RCT?

Answer 6

1. Lack or no ferrule
2. Wide post holes
3. Endodontic complications
   - Fractured instruments
   - Perforations
   - Short/long root fillings

Question 7

Restorations choices for RCTs

Answer 7

1. DIRECT RESTORATIONS
   - Composite
   - Class III and IV
2. INDIRECT RESTORATIONS
   - Crown/post crown
   - Veneer

Question 8

If a patient does not have intact marginal ridges, what restorative tx do we tend to go for?

Answer 8

Crowns/post crowns

Question 9

Restoration option for:

Anterior teeth with intact marginal ridges

Answer 9

Direct restoration

- Composite

Question 10

Restoration option for:

Anterior teeth with intact marginal ridges +/- discoloured crown (3)

Answer 10

Direct restoration
- Composite

• Bleaching
• Veneer

Question 11

Restoration option for:

Anterior teeth with marginal ridges destroyed

Answer 11

Core build up with crown

Question 12

Function of a post/core

Answer 12

Gain intraradicular support for a definitive restorations

Question 13

What does a core provide?

Answer 13

Retention for crown

Question 14

Where is a post placed?

Answer 14

Placed in the root canal

Question 15

What is the core?

Answer 15

What the prosthesis is cemented to

eg. crown or bridge abutment

Question 16

When do incisors/canines need posts?

Answer 16

When there’s extensive loss of coronal tooth tissue

As the pulp chamber and single root canal are not adeqaute to retain a core

Question 17

Why do we avoid posts in mandibular incisors?

Answer 17

Due to thin/tapering/narrow mesiodistal roots

Question 18

Why do we avoid posts in curved canals?

Answer 18

To avoid perforations

Question 19

What is a ferrule

Answer 19

Dentine collar

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

Question 20

Function of a ferrule

Answer 20

Prevents tooth fracture

If crown margin is not placed onto solid tooth, root fracture significantly increased

Question 21

Advantages of prefabricated posts (3)

Answer 21

1. Only 1 visit required vs 2 for custom posts
2. No impressions + no fit visit required
3. Chairside core build-up

Question 22

What instruments do we use to remove a post?

Answer 22

1. Ultrasonics
2. Masseran Kit
3. Eggler
4. Moskito Forceps

Question 23

Most common reason for post crown failure

Answer 23

Restorative reasons

- Caries around crown margins