endo access Flashcards
objectives of access
gain access to pulpal space and maintain tooth strength
To Gain Access
to the pulpal
space for:
- Visualization
- Instrumentation
- Obturation
how to maintain strength of tooth w access
- Preserve Incisal Edge
- Conserve Marginal Ridges
- Maintain correct Shape, Size & Position
max CI outline
Triangular with the base of the triangle toward the incisal edge
max LI outline
follow the same form as CI but are narrower and less flared incisally
max C outline
also have the same general form but are closer to an oval
where is pulp usually found in regards to ant max teeth
Usually in the center mass of the root form.
man CI and LI outline
are very narrow and have 2 canals 40% of the time so the access is very narrow M-D and extends further incisally
man c outline
similar to max c
danger with Man incisors
BEWARE: Mandibular Incisors are VERY NARROW M-D
We must be AWARE of this to avoid ruining the tooth by
tipping our access bur to the mesial or distal and drilling
out the side of the tooth
We must VISUALIZE the angulation of the unseen root in
both M-D and B-L directions
what must be understood of tooth we are accessing
Crucial to have a visual and spatial understanding of the tooth/pulp you are attempting to access
Don’t ever look for the canals with?
Don’t expect to always feel?
You will find the ______ first
Don’t ever look for the canals with the bur
Don’t expect to always feel a “drop” into the
pulp chamber
You will find the roof of the pulp chamber first
what mark should be made on the bur?
7mm, if chamber not found by this deep call faculty
unroofing of the chamber can be done with?
round bur or endo Z
IF you don’t know for certain where you are:
STOP & TAKE A RADIOGRAPH
*Have someone else take a look
*Don’t become DISORIENTATED
too much removal of tooth structure for access will?
weaken tooth and increase risk of fracture
angles, caries, marg ridges, mm on alll sides
Access: Maxillary Central Incisor
*Triangular access (base of
triangle at incisal)
“Incisal compromise”
Total straight-line access on all anteriors would involve access from the facial and create a weakening of the incisal edge and an esthetic issue.***
ideal max CI access restoration
would
not require a crown and
could be adequately
restored with a
composite restoration.
bur,shape, root
Access: Maxillary Lateral Incisor
use 2 round bur
*Triangular/Oval Access
*Thinner root than central (narrower access M-D narrower pulp horns)
*“Incisal Compromise” on all anterior teeth
bur, shape, canals narrower in which plane, root/canal
Access: Maxillary Canine
Use #2 or #4 round bur
*Oval access
*Canal narrower M-D than F-L
*One root (larger and longer than lateral)
*USUALLY SINGLE CANAL (most max. anteriors)
Access: Mandibular Incisors bur
2 round
man incisors access
*Root wider which way?
*Very narrow which way?
*One canal/ Two canals?
*When two canals-mostly Type?
*Cervical access will miss?
*Root wider F-L than M-D
*Very narrow M-D (easy to perforate to side
of root)
*One canal 60% Two canals 40%
*When two canals-mostly Type II (See
Weine)
*Cervical access will miss Lingual canal
how often does a man LI have two canals
44%
common canal configurations
*Type I: one canal from pulp chamber to apex
*Type II: 2 canals from pulp chamber, join prior to apex
*Type III: 2 canals from pulp chamber to apex
*Type IV: one canal from pulp chamber divides prior to apex (most difficult to treat)
outline
Maxillary first premolars canals, MD width, bur,
Maxillary first premolars have a B. & a L. canal in at least 85% of cases. M-D width of the access is no wider than a #4 round bur and the opening usually
extends from near the tip of the buccal cusp lingually as a narrow oval.
canal(s), where canal located
Maxillary second premolars outline
contain a second canal in at least 35% of cases and the access form is very similar to the first PM. If there is a single canal, it is centrally located and wide from B to L.
PM easy to perf? how to combat?
All premolars are very easy to perforate to the mesial or distal! Use #2 bur and align carefully with root
angulatio
Access on posteriors from the _______- surface always
***Access always gained through the occlusal approach on all posterior teeth.
#canals %, where canal orfices located, width of root/access?
Access: Maxillary 1st Premolar
Thin Oval Access (width of #4)
Thin M-D root
Two canals most prevalent
85% two canals
9% one canal
6% three canals
Canal orifices lie under respective cusp tips
most common error of the max pm
Not totally unroofed
Most Common Error
max PM1 access
bur? remove? finish with? no wider than?
Use a #2 round bur
remove pulpal roof
finish with ENDO-Z bur
FINAL WIDTH OF ACCESS IS NO WIDER THAN #4 ROUND BUR
max PM2 has two canals ___% of the time
23%
Access: Maxillary Second Premolar
width/shape?
Slightly less_______extension than 1st
Most often Type what canals?
root number?
If one canal found but not in center F-L this means?
beware of what type of canals?
Access: Thin oval (width of #4)
Slightly less F-L extension than 1st
Most often Type I 1 root 1 canal (75-85%); Type II, III & IV less frequently
2 roots (15 -25%)
3 roots very rarely
If one canal found but not in center F-L, there are probably 2 canals, Beware Type IV, very hard to shape, clean and fill
Mandibular PMs also have a very narrow _______width and access
extends from near the tip of the _______ cusp ________
Mandibular PMs also have a very narrow M-D width and access
extends from near the tip of the buccal cusp lingually.
2 canals at PMs often?
rare and difficult
how to find 2nd PM canalswith radiographs
fast breaks
Access:Mandibular First Premolar
Access shape
Usually how many root/canal?
Type III?
Three canals ?
Access: thin oval
Usually one root, 1 canal
(type I), 73.5 %
Type III, 19.5 %***
Three canals less than 1%
Vertucci study
law of color change
The color of the pulp chamber
is always darker than the surrounding walls.
law of centrality
law of concentricity
law of the CEJ
what tool should we use to find the canal entrance
endo explorer
M or PM access more difficult? why?
molars
Attention to detail is much more complicated and compacted into a smaller area
Many new opportunities to mess up are presented
worst error of access
perforation
shape? why?
first man molar access
common probability of 2 distal canals (30%), we feel the wisest plan is to use the TRAPEZOIDAL FORM with rounded angles as shown.
The wider base of the form is to the Mesial (taking care to preserve the mesial marginal ridge) and extending only as far distally as to provide clear
access to the distal canals or canal.
missed canal?
failed RCT
when can you tell if the 1st man molar has 3/4 canals
when you enter pulp
where would a singular D canal be on man M1
mid distal
symmetry rule
B/L canals will be equidistant from a line drawn MD
what can be seen at pulpal floor to lead to canal entry
dev black lines
mostly seen at which M?
c shaped and middle mesial canals at Man M’s
2-8 % VARIABLE
tooth contains 3 or more canals associated by an irregular network of thread-like canals and areas that are variable in size, shape and complexity and are extremely difficult to find and worse to instrument. These are largely seen in 2nd molars.
Second molars in general are considerably more difficult than 1st molars which explains why Advanced Endo does all 2nd molars.
third molar RCTs?
rarele done, little reason
maxillary M canals, challenge?
4 canals most of the time (95%)
MB2 is biggest challenge, hard to find and thin
max molars canal layout
bur used to define the
walls as they meet the floor of the prep.
Endo Z
law of sym does not apply to?
max molars
are max molar variation rare? what to do with them?
not rare, refer
Maxillary Molars are mechanically difficult why?
Maxillary Molars are mechanically
difficult as the MB2 canal may require
exceptional skill in locating and
shaping.
MB2 may require as much TIME as all
3 other canals in total !
max I mutiple canals?
rare
man incisors variations
Single root + 1 canal = 60%
Single root +2canals = 40%
max canines variations
multi canals rare
man canine variations
Single canal = 78%
2 canals = 22%
max PM1 variations
2 Canals = 85%
Single canal = 9%
3 Canals = 6%
max PM2 variations
Single canal = 50%
2 canals = 50%
Man PM1 variations
single canal = 74%
2 canals = 25%
3 canals = 1%
man PM2 variations
single Canal = 98%
2 canals = 2%
max M1 root and canals %
3 roots & 4 canals = 95%
3 roots & 3 canals = 5%
max M2 variations
3 roots 4 canals = 60%
3 roots & 3 canals = 40%
man M1 variations
how many roots?
hw many canals at each?
rare case?
Usually 2 roots
Mesial = 2 canals 98%, 1 canal = 2%
Distal = 1 canal 70%, 2 canals 30%
Rare = 3 roots + 4 canals
man M2 variations
2 roots + 3 canals = 81%
2 roots + 2 canals = 15%
1 root + 1 canal = 4%
