Obturation

Question 1

describe a successful obturation

Answer 1

• absence of pretreatemnt peri-apical lesion
• root canal filling with no voids
• obturation to within 2mm of apex
• adequate coronal seal

Question 2

why is obturation necessary

Answer 2

reduce coronal leakage and bacterial contamination

Question 2

what type of seal are we wanting for endo

Answer 2

fluid tight or bacterial tight seal

Question 3

when is one visit rct preferred

Answer 3

1. vital pulp tissue
   - bacterial contamination is minimal
   -prevent contamination via leakage between visits
2. necrotic pulp tissue - with or without asymptomatic periapical pathology - asymptomatic peri apical periodontitis, condensing osteitis

Question 4

what are the guidelines for single visit rct

Answer 4

• no signficant symptoms
• no significant clinical signs
• canal must be clean and dry

Question 5

how long is sufficient for CAOH to be in the canal for sufficient disinfection

Answer 5

1 week

Question 6

where does the AC lie from the radiographic apex

Answer 6

0.5-1mm from radiographic apex

Question 7

name the obturation techniques

Answer 7

• cold lateral compaction
• warm vertical compaction
• continous wave condensation
• single cone obturation

Question 8

name the obturation technique we use

Answer 8

cold lateral compaction

Question 9

what size of spreader should we use for obturation

Answer 9

size B

Question 10

technqiue for cold lateral comapction (tell me the stages)

Answer 10

1. LA
2. rubber dam
3. swab tooth with alcohol
4. irrigate with citric acid to remove CAOH then sodium hypochlorite
5. take a cone fit radiograph (GP should be 1mm from radiographic apex)
6. insert finger spreader 1-2mm short of WL
7. dry canals with paper points
8. mix sealer and have spreader ready
9. coat MAC into sealer and insert into canal
10. insert finger spreader 1-2 short of WL - leave for 15 secs
11. remove spreader and insert accessory cones
12. repeat this process until no further accessory cones can be fitted
13. cut off excess GP with heated instrument (using an endodontic plugger)

Question 11

what can be placed in the entrance to root canals to minimise coronal leakage

Answer 11

resin modified GI (vitrebond)
smart dentine replacement (SDR)

Question 12

what is smart dentine replacement (SDR)

Answer 12

a flowable bulk filler that can be placed up to 4mm, self levels and minimise shrinkage stress

• etch and bond access cavity prior to placing SDR