root canal obturation

Question 1

why obturate>

Answer 1

1) need to reduce coronal leakage and bacterial contamination
2) seal apex from periapical fluids
3) entomb remaining irritants in the canal

Question 2

why are RCT successful

Answer 2

1) residual bacterial threshold -> below it will not have disease

Question 3

hermetic seal vs water tight seal

Answer 3

1) water tight is what we are going for

Question 4

ideal obturation

Answer 4

1) densely packed, no voids, within 2 mm of apex, quality coronal restoration

Question 5

when can you obturate

Answer 5

1) no swelling
2) when you can get the canal dry
3) no significant difference in success between one visit and two visits
- systematic review / meta-analysis

Question 6

idea obturation material

Answer 6

1) nonirritating, impervious to moisture
2) inhibit bacterial growth
3) sterilize it
4) take it out easily
5) etc etc

Question 7

composition of gutta percha

Answer 7

1) 65% zinc oxide
2) 20% gutta percha
3) 10% opacifiers
4) 5% waxes and resins

Question 8

physical properties of gutta percha

Answer 8

1) trans isomer of natural rubber
2) gutta percha exists normally in the beta (semi crystalline state) at room temperature
3) transforms to alpha phase upon heating (tacky flows)
4) compactable, not compressible

Question 9

types of GP points

Answer 9

1) non standardized

Question 10

is latex allergy a concern with GP

Answer 10

1) GP did not cross react with latex, and some points with gutta balata will
- so check the ingredients

Question 11

sealer is necessary

Answer 11

1) canals obturated with sealer alone dissolve over time
2) 100% leakage of silver point without sealer
- need sealer

Question 12

properties of ideal sealer

Answer 12

1) most are cytotoxic when mixed
- reduced upon setting

Question 13

type of sealers

Answer 13

1) resin
2) zinc oxide eugenol
3) seal apex with CaOH
4) bioceramic sealer

Question 14

lateral vs vertical compaction of GP

Answer 14

1) warm vertical compaction is more technique sensitive

Question 15

what are bioceramics

Answer 15

1) highly biocompatible
2) similar characteristics to tissue
3) calcium silicate/phosphate
- for root canal sealing
4) stimulate healing
5) set in presence of moisture
6) not difference between single cone obturation and other technicques at 12 mo

Question 16

irrigation protoal

Answer 16

1) sodium hypochlorite
2) ultrasonic irrigation
3) EDTa
4) sodium hypochlorite

Question 17

dry the canal

Answer 17

1) paper points must be measured
2) dry the canal before obturation

Question 18

try the cone

Answer 18

1) take the cone, and see if there is tugback

Question 19

single cone obturation

Answer 19

1) use a bioceramic sealer
2) careful of extrusion
3) bioceramic sealers are soluble

Question 20

disinfecting GP

Answer 20

1) one minute soak in sodium hypochlorite
2) dry with sterile gauze

Question 21

how to place the sealer

Answer 21

1) no significant difference in method of placing sealer into the canal, but need to coat the canal walls
2) put sealer on the cone
- make sure master cone is coated all the way around the aprical third
- coat all bald spots
3) if necessary, use finger spreader to fill coronal voids
- use red spreader with about 5 pounds of force
- spin it about 15-20 times
- you should be able to see the hole

Question 22

medium fine accessory point

Answer 22

1) coat it with sealer
2) use the mirror
3) put the cone in the hole made by the spreader and it should seat to place
4) if the cone bends, get another one
5) stope when finger spreader goes about 1 mm into it

Question 23

sear off coronal GP

Answer 23

1) 200C
2) condense the GP until it cools

Question 24

silver points

Answer 24

1) no one really uses anymore
2( they are round

Question 25

thermafil

Answer 25

1) GP on a stick
2) leaks due to stripping of old GP
2) complete encasement never seen

Question 26

sagenti N2 paste

Answer 26

10 below standard of care
2) no length control