Lecture 12

Question 1

EDTA has a concentration of:

Answer 1

17%

Question 2

T/F: with careful planning and execution it is possible to instrument all pulpal spaces:

Answer 2

False

Question 3

T/F: the primary method of irrigation with NaOCl to avoid incident is to never allow the syringe tip to bind in the canal

Answer 3

True

Question 4

Which of the following functions is NOT accomplished by NaOCl?

a) disorganizes biofilm
b) dilutes toxins in the canal system
c) removes the smear layer
d) dissolves tissue substrate within the canals
e) lubricates the canal system

Answer 4

c) removes the smear layer

Question 5

What is the minimum time for NaOCl to function in the prepared canal to be effective?

Answer 5

30 minutes

Question 6

We must remove and destroy both _____ & ____ to be successful

Answer 6

Bacteria & their substrate

Question 7

Instrumentations allows for access of a complex anatomy by ______%

Answer 7

60-70%

Question 8

What is NaOCl comprised of?

Answer 8

8.3% sodium hypochlorite (bleach)

Question 9

Our major weapons: cleaning and shaping with

Answer 9

NaOCl & intra-canal medicaments

Question 10

You MUST NOT have the tip of the syringe:

Answer 10

beyond apical constriction

Question 11

Where should you set the bend of the tip of the syringe?

Answer 11

2 mm short of WL

Question 12

When NaOCl breaks down, what do we have?

Answer 12

NaCl & H2O

Question 13

NaOCl becomes inactive after:

Answer 13

3-5 min in the canal

Question 14

NaOCl becomes inactive after 3-5 min in the canal so it must be:

Answer 14

replenished every 3-5 min

Question 15

It is important that you irrigate with NaOCl following:

Answer 15

each active instrumentation

Question 16

What is often used for surface disinfection? What is it comprised of?

Answer 16

Dakin’s solution; o.25% NaOCl

Question 17

Compared to Dakins solution 8.3% NaOCl (Clorox) is ____ times stronger and more _____ also more _____

Answer 17

33.2x stronger; toxic; effective

Question 18

A typical case requires about ______ cc of NaOCl as irrigant per visit

Answer 18

10-12 cc

Question 19

NaOCl must be in contact with the shaped canal a minimum of ____ after the canal is enlarged to _____ or larger

Answer 19

30 min; #30

Question 20

A canal smaller than #30 will seldom if ever allow:

Answer 20

any irrigant to reach the apical 1/3 of the canal

Question 21

What does recapitulation mean?

Answer 21

1. flood canal system with NaOCl
2. repeat every 3-5 min
3. move on with next active instrument

Question 22

Sodium hypochlorite:

1. is a strong _____
2. powerful _____
3. dissolves necrotic tissue at _____ concentrations
4. dissolves living tissue at _____ concentration

Answer 22

1. oxidizer
2. disinfectant
3. low concentration
4. high concentration

Question 23

What is the med of choice in endodontics?

Answer 23

Sodium hypochlorite (NaOCl)

Question 24

Vigorous injection will cause irrigant to:

Answer 24

express apically

Question 25

To avoid NaOCl incidents: 1. Do NOT: 2. Keep: 3. Dental dam:

Answer 25

1. let tip bind 2. tip moving & loose in the canal 3. must NOT leak

Question 26

What results with NaOCl incidents? (NaOCl forced out the end of the tooth into the P/A tissues)

Answer 26

1. immediate & extreme pain for several days 2. ecchymosis 3. swelling 4. temporary disfigurement 5. court appearance

Question 27

This device agitates irrigation solutions during endodontic treatment:

Answer 27

endo activator

Question 28

T/F: Evidence-based endodontics show that cavitation and acoustic streaming significantly improve debridement and the disruption of the smear layer and biofilm

Answer 28

True

Question 29

List the sizes of the following endo activator tips: A) Small B) Medium C) Large

Answer 29

A) 15/02 B) 25/04 C) 35/04

Question 30

T/F: Using an endo activator diminishes the time needed for irrigation

Answer 30

False

Question 31

Produced when we do any mechanical shaping in dentin; it lies on the surface of the dentinal tubules:

Answer 31

smear layer

Question 32

Occludes access to the dentinal tubules so MUST be removed to complete the cleaning procedure before obturation or when using various sealers and cements:

Answer 32

smear layer

Question 33

When must the smear layer be removed?

Answer 33

BEFORE obturation

Question 34

What is introduced into the canal system and allowed to work for 60 seconds?

Answer 34

17% EDTA