Lecture 12 Flashcards
EDTA has a concentration of:
17%
T/F: with careful planning and execution it is possible to instrument all pulpal spaces:
False
T/F: the primary method of irrigation with NaOCl to avoid incident is to never allow the syringe tip to bind in the canal
True
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
c) removes the smear layer
What is the minimum time for NaOCl to function in the prepared canal to be effective?
30 minutes
We must remove and destroy both _____ & ____ to be successful
Bacteria & their substrate
Instrumentations allows for access of a complex anatomy by ______%
60-70%
What is NaOCl comprised of?
8.3% sodium hypochlorite (bleach)
Our major weapons: cleaning and shaping with
NaOCl & intra-canal medicaments
You MUST NOT have the tip of the syringe:
beyond apical constriction
Where should you set the bend of the tip of the syringe?
2 mm short of WL
When NaOCl breaks down, what do we have?
NaCl & H2O
NaOCl becomes inactive after:
3-5 min in the canal
NaOCl becomes inactive after 3-5 min in the canal so it must be:
replenished every 3-5 min
It is important that you irrigate with NaOCl following:
each active instrumentation
What is often used for surface disinfection? What is it comprised of?
Dakin’s solution; o.25% NaOCl
Compared to Dakins solution 8.3% NaOCl (Clorox) is ____ times stronger and more _____ also more _____
33.2x stronger; toxic; effective
A typical case requires about ______ cc of NaOCl as irrigant per visit
10-12 cc
NaOCl must be in contact with the shaped canal a minimum of ____ after the canal is enlarged to _____ or larger
30 min; #30
A canal smaller than #30 will seldom if ever allow:
any irrigant to reach the apical 1/3 of the canal
What does recapitulation mean?
- flood canal system with NaOCl
- repeat every 3-5 min
- move on with next active instrument
Sodium hypochlorite:
- is a strong _____
- powerful _____
- dissolves necrotic tissue at _____ concentrations
- dissolves living tissue at _____ concentration
- oxidizer
- disinfectant
- low concentration
- high concentration
What is the med of choice in endodontics?
Sodium hypochlorite (NaOCl)
Vigorous injection will cause irrigant to:
express apically
To avoid NaOCl incidents:
- Do NOT:
- Keep:
- Dental dam:
- let tip bind
- tip moving & loose in the canal
- must NOT leak
What results with NaOCl incidents? (NaOCl forced out the end of the tooth into the P/A tissues)
- immediate & extreme pain for several days
- ecchymosis
- swelling
- temporary disfigurement
- court appearance
This device agitates irrigation solutions during endodontic treatment:
endo activator
T/F: Evidence-based endodontics show that cavitation and acoustic streaming significantly improve debridement and the disruption of the smear layer and biofilm
True
List the sizes of the following endo activator tips:
A) Small
B) Medium
C) Large
A) 15/02
B) 25/04
C) 35/04
T/F: Using an endo activator diminishes the time needed for irrigation
False
Produced when we do any mechanical shaping in dentin; it lies on the surface of the dentinal tubules:
smear layer
Occludes access to the dentinal tubules so MUST be removed to complete the cleaning procedure before obturation or when using various sealers and cements:
smear layer
When must the smear layer be removed?
BEFORE obturation
What is introduced into the canal system and allowed to work for 60 seconds?
17% EDTA
