Endodontic Access Flashcards
Why do you need to gain access to the pulpal space?
- Visualization
- Instrumentation
- Obturation
How do you maintain the strength of a tooth during an access?
- Preserve Incisal Edge
- Conserve Marginal Ridges
- Maintain correct Shape, Size & Position
Crucial to have a _____________ understanding of the tooth/pulp you are attempting to access
visual and spatial
What is red?
What is orange?
What is yellow?
What is green?
What is blue?
What is purple?
What is pink?
T/F: you should look for a canal with the bur
FALSE!
- use the endo explorer
If you don’t find the pulp chamber at __ mm STOP
7
Maxillary central incisors are ___________ with the base of the triangle toward the incisal edge
triangular
What is the difference between maxillary laterals compared to the central?
narrower and less flared incisally
Maxillary canines have the same general form as the incisors but are closer to an _______ shape
oval
What does the law of centrality state?
Penetration points are where you generally expect to find the pulp and are usually in the center mass of the root form
Where are the penetration points for the maxillary anteriors?
Mandibular central & lateral incisors are very narrow and have 2 canals ___% of the time
40%
Mandibular central & lateral incisors have an access that is…
very narrow M-D and extends further incisally
Mandibular canines are ______ shape and similar to maxillary canine access
oval
Mandibular Incisors are VERY NARROW _____
M-D
What do you need to be aware of with mandibular incisors?
- 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
What type of access is used on a maxillary central incisor?
triangular access (base of triangle at incisal)
On a maxillary central incisor with access there should be about ___ mm of unprepped tooth on all sides
3
Total straight-line access on anteriors would involve access from the facial and create a…
weakening of the incisal edge and an esthetic issue
Make a mark on your entry bur at ___ mm with a permanent marker
7
What would the ideal access of a maxilalry central incisor include?
- would not require a crown
- could be adequately restored with a composite restoration
What are the types of burs used for access?
Safety-tip tapered diamond bur
What should you do if you don’t know for certain where you are in the tooth?
*STOP & TAKE A RADIOGRAPH
*Have someone else take a look
*Don’t become DISORIENTATED
What bur do you use to access a maxillary lateral incisor?
2 round
What kind of access do you do on a maxillary lateral incisor?
triangular/oval access
What is important to know about “incisal compromise”?
Total straight-line access on anteriors would involve access from the facial and create a weakening of the incisal edge and an esthetic issue.
What bur do you use to access a maxillary canine?
2 or #4 round bur
What kind of access do you do on a maxillary canine?
oval access
The canal of a maxillary canine is narrower in what direction?
narrower M-D
How many canals do most maxillary anteriors have?
single canal
What does the law of color state?
the floor of the chamber is darker than the walls of the chamber
What bur do you use to access a mandibular central incisor?
2 round bur
What type of access is used on a mandibular central incisor?
oval access
What percent of the time is there one canal in a mandibular central incisor?
60%
- two canals 40%
Cervical access of a mandibular central incisor will miss the _________ canal
lingual
The root of a mandibular central incisor is wider in what direction?
F-L
What are the common canal configurations for premolar access?
Type I
Type II
Type III
Type IV
What is a type I premolar access?
one canal from pulp chamber to apex
What is a type II premolar access?
2 canals from pulp chamber, join prior to apex
What is a type III premolar access?
2 canals from pulp chamber to apex
What is type IV premolar access?
one canal from pulp chamber divides prior to apex (most difficult to treat)
Maxillary first premolars have a B. & a L. canal in at least ___% of cases.
85%
For a maxillary first premolar the M-D width of the access is no wider than a ___________ and the opening usually extends from near the tip of the buccal cusp lingually as a narrow oval
4 round bur
Maxillary second premolars contain a second canal in at least ___% of cases
35%
What do you need to worry about for maxillary premolars?
All premolars are very easy to perforate to the mesial or distal! Use #2 bur and align carefully with root angulation.
Access always gained through the ____________ approach on all posterior teeth
occlusal
What kind of access and what bur for a maxillary 1st premolar?
Thin Oval Access (Bur #2)
What is the most prevalent canal type for a maxillary 1st premolar?
Two canals most prevalent
85% two canals
9% one canal
6% three canals
In premolars canal orifices lie under respective…
cusp tips
What is the most common error when accessing a maxillary 1st premolar?
not totally unroofed
Final width of access for a maxillary 1st premolar is not wider than a…
4 round bur
What are the steps to access a maxillary 1st premolar?
- use a #2 round bur
- remove pulpal roof
- finish with ENDO-Z bur
What kind of access and what bur for a maxillary 2nd premolar?
Thin oval (width of #2)
What type of canal configuration is the maxillary 2nd premolar?
- Most often Type I = 1 root 1 canal (75-85%)
- Type II, III & IV less frequently
What percent of the time does the maxillary 2nd premolar have two canals?
35%
What is the difference between the maxillary 2nd premolar compared to the first?
Slightly less F-L extension
If one canal found but not in center F-L, there are probably…
2 canals
What is the access for a mandibular first premolar?
thin oval
Mandibular 1st premolar is usually one root, 1 canal (type I) ____% of the time
73.5%
Mandibular 1st premolar is type IV ____% of the time
19.5%
Mandibular 1st premolar has three canals less than ____% of the time
1%
What is the law of concentricity?
walls of the pulp chamber are always concentric to the external surface
What is the law of the CEJ?
CEJ is the most consistent landmark for locating the position of the pulp chamber
What it the law of centrality?
pulp chamber in the center of the tooth
What is the biggest challenege with accessing maxillary molars?
MB2 canal
- as often as 95%
Maxillary Molars are __________ difficult because the MB2 canal may require exceptional skill in locating and shaping.
mechanically
_____ may require as much TIME as all 3 other canals in total !
MB2
As many as ___% of Maxillary Molars have 4 canals
95%
Four canals makes _______________________ far more difficult in that the MB2 canal is minute, dangerous and very time-consuming to find and to negotiate and to shape
Maxillary 1st Molars
If you are NOT consistently finding and successfully treating this MB2 canal, you are doing the patient a disservice and should…
STRONGLY CONSIDER REFERRAL before the Malpractice Actions begin
Endo-Z bur is used to…
define the walls as they meet the floor of the prep
With mandibular molars you often cannot tell if there are 3 or 4 canals in the tooth until you…
enter the pulp
If it is a singular distal canal generally in the ______ of the form as illustrated and it may be wide B-L.
center
About ____% of mandibular molars have 2 distal canals so it is worth looking for them every time.
30%
What is the shape of the access for mandibular molars with 3 canals?
Triangular Shape
What is the shape of the access for mandibular molars with 4 canals?
Rhomboid shape
Mandibular molars have C-shaped canals _____% of the time
2-8%
The “C-Shaped Canal” tooth contains __________ canals associated by an irregular network of threadlike canals and areas that are variable in size, shape and complexity and are extremely difficult to find and worse to instrument.
3 or more
Second molars in general are considerably more difficult than 1st molars which explains why…
Advanced Endo does all 2nd molars
_____ molars are very rarely done in endo
Third
_______ RCT is monumentally more difficult than anteriors and PM
MOLAR
__________ is arguably the WORST error you can make at access
Perforation