Endodontic Disinfection Flashcards
instrumentation fails to:
contact a large portion of the hidden spaces which are filled with bacteria and substrate
what needs to be removed from canal for RCT to be successful
remove and destory bacteria and their sbustrate
what percentage of areas can be accessed with instrumentation
60-70%
since not all areas can be accessed with instruments what is used in adjunct with it
- 8.3% sodium hypochlorite (NaOCl)
what do we clean and shape with
NaOCl and intra canal medicaments
how long should the needle be
2mm from working length
should the needle be bent or straight
bent
tip of syringe cannot pass beyond:
apical constriction
do not allow tip to ____ in the canal
bind
what does NaOCl do
- kills micro-organisms on contacts
- destroys and dissolves substrate
- disorganizes biofilm
- dilutes toxins in canal system
- disinfects RC system and instruments
- lburicates canals
- floats out debris
when NaOCl breaks down what do we have
NaCl and water
when does NaOCl break down
in the bottle and in the tooth
how long does it take for NaOCl to become inactive in the canal and when does it need to be replenished
after 3-5 minutes so it must be replenished every 3-5 minutes
irrigate following:
each active instrument
what is used for surface disinfection and what is the concentration of NaOCl
- Dakin’s solution
- 0.25%
what concentration of NaOCl do we use and how does it compare to Dakins solution
- 8.3%
- it is stronger and more toxic and more effective
typical case requires ____ of NaOCL as irrigant per visit
10-12cc
NaOCl must be in contact with shaped canal a minimum of _______ after canal enlarged to a ___ or larger
- 30 minutes
- # 30
what does recapitulate mean
-flood canal system with NaOCl
- do this every 3-5 minutes
- then move on with next active instrument
when should you recapitulate
following each active instrument
how big is the syringe we get
12cc
describe sodium hypochlorite
- strong oxidizer
- powerful disinfectant
- dissolves necrotic tissue at low concentration
- dissolves living tissue at higher concentration
- med of choice in endo
describe sodium hypochlorite
- strong oxidizer
- powerful disinfectant
- dangerous and extremely toxic
what do you do if sodium hypoclorite is swallowed
- call poison center
- dental dam must not leak
what do you do if contact with eyes and sodium hypochlorite
flush with water for 15 minutes
- never forget eye protection and never pass anything over face
even with special tip:
- vigorous infection will cause irrgant to express apicaly
- be carefule
- do not let the tip bend
- keep moving and loose in canal
- tastes terrible in mouth and burns throat
- dental dam must not leak
what happens if irrigating needle is allowed to bind in canal
NaOCl can be forced out the end of the tooth into the PA tissues with disastrous results
what are the results of NaOCl leaking into PA tissues
- immediate and extreme pain for several days
- ecchymosis
-swelling - temporary disfigurement
can you undo NaOCl accidents
no you can only prevent them
why do you need to protect clothing
the tip od the syringe will leak as you remove it from the tooth
what does dr edwards suggest you do to protect clothes
place your gloved hand under the syringe as you remove it from the tooth
what does the sonic vibration of NaOCl endo activator do
- agitates irrigation solutions during endo treatment
- cavitation and acoustic streaming significantly improves debridement and the disruption of the smear layer and biofilm
when would the endo activator be helpful
in difficult and unusual canal systems
does endo activator diminish time for use of NaOCl
no
when is the smear layer produced
when we do any mechanical shaping in dentin
where is the smear layer
on the surface of dentinal tubules
is the smear layer removed by NaOCl
no
when should the smear layer be removed
before obturation or when using various sealers and cements to complete the cleaning procedure and to be able to access dentinal tubules
what is used to remove smear layer and for how long
17% EDTA and works for 60 seconds
what stops the action of EDTA
8.3% NaOCl
what does EDTA stand for
ethylene diamine tetra-acetic acid
what other irrigant is enouraged
2% chlorhexidine
why dont we think 2% chlorhexidine is necessary
no biofilm removal, precipitate formation
can we sterilize the RCS
no we can lower bacterial concentrations
when are intracanal medications placed
within the canal system between appointments
what is the goal of intracanal medications
increase local anti-microbial action and to further decrease the microbial challenge within the RC system
what is the intracanal medication of choice
Ca(OH)2
describe CaOH2
- ph between 11 and 12
- discourages most microbial growth
- long lasting- effectiv eover extended periods
- no reported allergic responses
- easy to apply and remove as a paste
- available in clinic as ultracal
all potential portals of entry/exit must be:
sealed creating a dense liquid tight (hermetic) seal “obturation” and final restoration to prevent leakage
what are we theoretically sealing in the canal
some micro organisms, toxins and substrate within the canal system
what are the main take home messages
- use NaOCl to dissolve organic tissue and to kill microorganisms
- use a needle that fits loosely 2mm from WL. irrigate with an in and out gentle movment
- replenish NaOCl every 3-5 minutes/after every active instrument
- EDTA removes inorganic portion of the smear layer
- CaOH: intracanal medication of choice- pH between 11 and 12
