Coronal Leakage

Question 1

Maximum tooth fragility is endo tooth with…

Answer 1

MOD

Question 2

1mm ferrule impact on fracture resistance?

Answer 2

doubles compared to no ferrule

Question 3

Coronal restoration main goal

Answer 3

prevent microleakage

Question 4

Where does microleakage occur

Answer 4

gaps between tooth structure and restorative materials

Question 5

Timespan of microleakage of endo treated tooth without restoration?

Answer 5

3-90d

Question 6

Microleakage minimized by rubber dam?

Answer 6

yes

Question 7

Good Endo with good restoration =
Good Endo with bad restoration =
Bad Endo with good restoration =
Bad Endo with bad restoration =

Answer 7

Good Endo with good restoration = 91%
Good Endo with bad restoration = 44%
Bad Endo with good restoration = 67%
Bad Endo with bad restoration = 18%

Question 8

Coronal vs Radicular microleakage?

Answer 8

coronal - restorative material and tooth

radicular - post/filling and root

Question 9

6 steps of endo protocol

Answer 9

1. Pros consult to determine if can restore
2. Recept PA and BW radiographs
3. Endo tests
4. Pulpal diag
5. periapical diag
6. endo recommendation (UG OR PG)

Question 10

Impact of coronal restoration on prognosis for endo teeth for anterior? post?

Answer 10

anterior - greatly improves

Post - not

Question 11

Restorative materials for

Answer 11

Cavit and IRM

3mm

Question 12

Restorative materials for > 3wk?

Answer 12

composite resin or RMGI

Question 13

What do posts do?

Reinforce teeth? When not necessary?

Answer 13

Retain final restoration

Do not reinforce, not necessary when sufficient structure present

Question 14

Use of rubber dam vs no use success %

Answer 14

dam - 93.3%

no dam - 73.6%

Question 15

Post placement:
dentin removal?
minimum GP apically
length vs root
length vs crown
width vs root
relationship vs crest of bone?

Answer 15

minimize removal of dentin
5mm GP
1/2 length of root in bone
1 and 1/3 length of crown, longer than crown - should be as long as possible without disturbing apical 5mm GP
1/3 width root in bone, 1mm dentin minimum
extend post-apical of crest of bone

Question 16

Impact on elastic modulus on root fracture?

Answer 16

want it to be similar - will dissipate

if post is higher modulus - will focus at apex –> fracture

Question 17

Risk of root perforation increases when doing what when placing posts?

Answer 17

severe alteration of natural shape of canal

Question 18

Post diameter vs…
retention
fracture
perforation

Answer 18

no effect
increases
increases

Question 19

When is core indicated (2)?

Answer 19

1. replacement of missing coronal structure

2. resistance

Question 20

Disadvantages of composite and amalgam?

Answer 20

composite - leaking due to shrinkage

amalgam - no adhesion to tooth structure

Question 21

Crown indicated when?

Answer 21

better esthetics, or when structural integrity of natural tooth compromised

Question 22

Minimum ferrule?

Answer 22

1-2mm

Question 23

Purpose of ferrule?

Answer 23

Resists fracture, horizontal movement, increases retention

Question 24

What to do if need RTC on an existing crown with caries?

Answer 24

remove crown and caries first