Endodontic Materials Flashcards
why are metal files used
remove soft and hard tissues
remove microorganisms
create space for disinfectants
create shape for obturation
what is stress concentration point on a file
abrupt changes in geometric shape of a file that leads to higher stress at that point
what is work hardening
strengthening of a metal by plastic deformation
crystal structure dislocation
what is nitinol
alloy of nickel and titanium
what does irrigation do
facilitate removal of debris
lubrication
dissolution of matter
penetrate to canal periphery
kill bacteria/yeasts/viruses
biofilm disruption
biological compatibility
what is responsible for antibacterial activity
hypochlorous acid made from sodium hypochlorite
what factors are important for sodium hypochlorite function
concentration
volume
contact
mechanical agitation
exchange
what is the smear layer made of
organic pulpal material and inorganic dentinal debris
what is the effect of the smear layer
bacterial contamination, substrate and interferes with disinfection
prevents sealer penetration
how do you remove the smear layer
17% EDTA
10% citric acid
what is the volume of sodium hypochlorite used per canal and for how long
30ml at least 10 minutes after canal preparation
what is the concentration of sodium hypochlorite used
3%
what does EDTA do
remove smear layer
what is the volume of EDTA used for canal
3ml
what is the concentration of EDTA used
17%
