Restorative Endodontic Interface Flashcards
what are the types of posts for crowns
direct posts
cast posts and cores
what is the indication for a direct post
need a lot of dentine left
what are the indications for cast post and cores
no ferrule - not sufficient dentine left
what should you always ask yourself if you are treating an anterior tooth
could you build up a core
does the tooth need a post now
what is included in the assessment of RCT
if you’re going to put a post in the tooth it requires a good quality RCT
was it dont using dam and hypochlorite
has it been leaking
how long ago was it done
what should you do if the original RCT was done without dam and hypochlorite
redo it
what are the favourable aspects for post design
parallel sided - avoids weding non-threading
cement retained
why should posts be parallel
avoids weding
why should posts be non-threaded
avoids incorporating stress
why should posts be cement retained
buffer between masticatory forces post and tooth
what should you asses when designing the restoration
how long will it be
have you got a ferrule
how wide
is canal straight
how much space for the core
how much GP should be left at the apex after the post
3-5mm
what is a ferrule preparation
can place crown margins on solid tooth tissues rather than restorative material
and have 1-2mm sound dentine extending supragingival 360 degrees around where you are going to place the post
what is a ferrule effect
when you put a crown on the post that has 1-2mm of dentine all around it and have bracing where the drown meets the ferrule prep
what does ferrule effect give
resistance to masticatory force and microleakage
what is important to consider when designing a core
taper and length
6 degree taper
2mm of clearance incisal for MCC
what are options for provisional restorations for post crowns
provisional post core crown temp bond
immediate denture
dressing
essex retainer
what is a potential pitfall of provisional post core crown
if patient is chewing can dislodge the temp and lead to microleakage
what can you use to soften gutta percha
super endo alpha or eucaliptus oil
what size gates gliddens should be used
minimum size 3
how much GP should be left for apical plug
3-5mm
what is a para post XP
endo post system for indirect casting technique
different drills
what is the narrowest post base tip
0.9mm in diameter -same as diameter of gates glidden 3
why do you need to use gates glidden 3 before using post system
because the tip diameter is the same as the narrowest post system bur tip
what is the diameter of the tip of a gates glidden 3
0.9mm
what would you use for a provisional post
provisional post
pro-temp and putty matrix
what is a burnout post
used for a tehcnique where you wax up post core in patients mouth and send to labe
what is the impression post
post placed into tooth whilst you take definitive restoration for indirect cast post
what should you do if you put the gates glidden in and you feel resistance
take it out and change angulation so you do not damage inside of the canal
what do the para post drills do
widen diameter of the post space
what do you need to do if the provisional para post is too long
get wire cutters to cut at the apical end - leave the pin bit in tact so it helps retain the para core
where should you trim the provisional para post to
2-3mm of the incisal edge of the adjacent tooth
how do you take a definitive impression for a post
use a putty wash - make sure the post is completely covered and then use impression material over the top
what is an anti-rotation notch/ groove used for
prevent rotational displacement
what is included in the lab prescription for a cast post and core
construct cast post and care
para post colour
core 6 degree taper
please leave 2mm space in occlusion for crown
what should you check when the post and core comes back from lab
check no residual temp bond
irrigate chlorhexidine 0.2%
dry paper points
ensure fits around prep
ensure enough occlusal clearance
why should you not fill the post space completely with cement
prevent it seating
what do you need to ensure after seating a provisional post core when taking an impression
no excess cement around the margins and no bleeding
what is a post crown considered
last resort
what are some methods of post removal
ultrasonic tips
trephan
eggler device
moskito forceps
sliding hammer
anthrogyr
what is an anthogyr
you tie wires round pontics and it gets it out
what is a fractured post removal
when it is below the dentine collar - consider referral to specialist
what are problems associated with post crown removal
cant remove it
root fracture
render tooth unrestorable
post space too wide
break the post
what is the fibre post system currently used
DT light post
what are some core materials for posterior teeth
composite - best
amalgam - out of fashion
glass ionomer - not really used as it absorbs water and core expands in size
what are paracore or biodentine used for
materials used for core retention in posterior teeth
how long do you need to wait after placing an amalgam core
24 hours
why do we try avoid posts in posterior teeth
narrower roots
disadvantages outweigh advantages
root canals usually curved
what is a nayar core
an amalgam based core - rarely used
what should you consider if treating a tooth that has a RCT
cut a cuspal protection restoration on the tooth
why do we put cuspal protection restoration on posterior teeth
prevent catastrophic failure
maintain coronal seal
prevents microbial ingress
