Common Materials used in conventional RCT

Question 1

What can be used to improve the seal in rubber dam?

Answer 1

Oraseal (foams) or liquid dam(painted on)

Question 2

What is the purpose of barbed broaches in rvt?

Answer 2

removal i..e cotton wool or nerve

Question 3

What slow speed bur is used in RCT?

2) what sizes do they come in?

Answer 3

spiral paste filler (for antimicrobial dressing material) gate-glidden drills
sizes 1-6

Question 4

what type of mirror is used in RCT?

Answer 4

front silvered mittor

Question 5

what lubricants and chelating agetns are used in RCT?

Answer 5

a) EDTA/ peroxide pastes e.g. Glyde, RC Prep, Filecare

b) Medicated soap, e.g. Hibiscrub

Question 6

what would the ideal irrigant achieve? (6)

Answer 6

1) flushes debris from canal
2) kills microorganisms
3) dissolves organic matter
4) lubricates instrumetns
5) non-toxid/irrigant
6) inexpensive

Question 7

What is the conc of NaOCl when used as irrigant in RCT?

2) this is the closest to ideal irrigant why?
3) what is the one issue with it?

Answer 7

1) 0.5-5%
2) flushes debris, antimicrobial, tissue solvent, lubricant, inexpensive
3) BUT irritant if dam leaks or if forced through root apex

Question 8

What are the different irrigants used in RCT?

Answer 8

1) NaOCl, chlorhexidine gluconate, chlorhexidine gluconate, sterile saline, water or LA,

Question 9

What are the issues with the use of sterile saline water, water or LA as an irrigant?

Answer 9

flushes debris, lubricant, non-irritant BUT no antimicrobial or solvent action

Question 10

What is the conc of hlorhexidine gluconatewhen used as irrigant in RCT?

2) why is it good?
3) what are the draw backs?

Answer 10

1) 0.2-2%
2) flushes debris antimicrobial, tissue solvent, lubricant, non-irritant
3) not cheap, no solvent action

Question 11

describe the cross section of the ISO K hand files then the ISO Hedstroem files?

Answer 11

K) triangle

H) tear drop

Question 12

How are irrigants delivered in RCT?

Answer 12

syringeand 27 and 30G endo irrigating needle, measured to prevent over extension (put a WL bend in it) , high-volume , low pressure

Question 13

what are the purposes of antimicrobial dressing materials?

Answer 13

clean and disinfect canal between appointment , kill microrganisms that leak in around the temporary dressing, possible prevent pain after canal prep

Question 14

what are the different of antimicrobial dressing materials?

3

Answer 14

1) non-setting calcium hydroxide paste
2) chlorhexidine gel
3) Odonto paste

Question 15

what is in odontopaste?

2) what affects do they have?

Answer 15

steroid / antibiotic (triamcinolone/clindamycin) paste
2) antimicrobial/ anti-inflammatory
clindamycin binds to the 50sR, stopping transpeptidation reaction, is a broad spectrum antibiotic
triamcinolone is a synthetic glucocorticoid, triamcinolone binds to and activates the glucocorticoid receptor, which leads to translocation of the ligand-receptor complex to the nucleus and induces expression of glucocorticoid-responsive genes such as lipocortins. Lipocortins inhibit phospholipase A2, thereby blocking the release of arachidonic acid from membrane phospholipids and preventing the synthesis of prostaglandins and leukotrienes, both mediators of inflammation.

Question 16

what do all the antimicrobial dressing materials have in common?

Answer 16

broad spectrum antimicrobial affects

Question 17

what are the 2 actions of non-setting CaOH cement?(how long can you leave it in tooth)
2) pH?

Answer 17

1) broad-spectrum antimicrobial for up to 3 months
and dissolves organic debris
2) 11/12

Question 18

how are antimicrobial dressing materials applied to canals?

Answer 18

file rotated anticlockwise
OR
spiral paste filler- careful hand or slow-speed

Question 19

what are the 2 functions of paper points?

Answer 19

drying canals and checking for bleeding

Question 20

What sealer cements (areas gutta percha can’t enter) are used?

Answer 20

zinc oxide-eugenol sealers
Resin (AH plus, 2seal)
Calcium silicates

Question 21

as a sealer cement, describe the properties of zinc oxide-eugenol sealers?

Answer 21

antimicrobial, variable setting time, widely used, can stain teeth yellow, can interfere with composite resins

Question 22

as a sealer cement, describe the properties of resin sealers?

Answer 22

slow setting (8hrs), antimicrobial, widely used, best scientific documentation

Question 23

as a sealer cement, describe the properties of calcium silicate sealers?

Answer 23

slow setting, non-staining, biocompatible, gaining documentation

Question 24

what does IRM stand for?

2) what is it composed of?

Answer 24

intermediate restorative material

2) ZOE cement reinforced with polymehyl methacrylate

Question 25

Temporary filling materials used in RCT:

1) What can be used in load bearing areas?
2) which are good in non-load bearing areas?
3) which are easy to remove due to colour?
4) what can be used in areas where aesthetics are a concern?
5) which is the most expensive option?
6) Which one comes pre-mixed? and sets in contact with saliva?

Answer 25

1) IRM (can last 1yr) and GIC
2) all (so ans to q1 and sedanol and Cavit)
3) IRM, Sedanol and Cavit
4) GIC
5) GIC
6) Cavit

Question 26

What minium thickness of temp filling material used in RCT?

2) What else is a requirement of the filling?
3) how are canal entrances protected?

Answer 26

1) 3mm
2) well adapted to cavity walls
3) cotton wool , sponge or PTFE tape

Question 27

How can fracture of RCT tooth be prevented before access cavity is cut?

Answer 27

take out of occlusion and apply endo bands,

cutting out of occlusion also provides point to measure from for hand instruments

Question 28

What are the 2 types of dead pulp?

2) What is the difference?

Answer 28

1) liquefactive pulp necrosis (due to entrance of bacteria possible caused by tooth wear, caries or iatrogenic damadge (20% of CR teeth develop AP) and sterile , ischaemic pulp necrosis (due to loss of perfusion , possible caused by trauma)