L1- Policies, Access, and Working Length Flashcards
1
Q
what are the objectives of endo
A
- correctly diagnose diseases as LEO
- perform quality NS endodontic therapy
- restore and document healed outcome
2
Q
what is the extreme service to the patient in endo (goal)
A
- relieve acute pain
- retain otherwise lost natural tooth
3
Q
most failures on WREBS and ADEC are due to:
A
poor access
4
Q
what is the access procedure for the outline
A
- create outline form just through enamel with number 2 round or 330 bur high speed
- the bur is somewhat perpendicular to lingual surface of tooth
- stay shallow, just through enamel - less than 1mm
5
Q
what is the access procedure for penetration
A
- penetrate pulp chamber roof with bur angled approaching parallel to long axis of root in center of outline form
- you should reach the pulp in most cases by 7mm
- confirm pulp canal entry with endodontic explorerDG16: PUSH
6
Q
describe the access procedure- un-roofing
A
- un-roof pulp chamber with brushing out-strokes. do not gouge axial walls
- remove obstructions and smooth the walls
- irrigate well (NaOCl): vision, remove debris, begin disinfection
7
Q
what is the access procedure- refining
A
- refine access prep with safe ended diamond bur or endo-Z bur to help provide straight line access to mid root - mostly in molar access
- the non-cutting tip is simply a pilot
8
Q
the endo - Z bur is a ____ cutting instrument only
A
side
9
Q
after access, your next big task is:
A
working length
10
Q
what is the correct WL
A
1mm short of the canal exit
11
Q
when do you measure the canal exit
A
before you mount the tooth
12
Q
how do you find the canal exit in the mouth
A
- chart
- apex locator
- radiograph with a #15 file in canal
13
Q
what is the average root length for central incisors
A
- max: 22.5
- mand: 20.7
14
Q
what is the average root length for lateral incisors
A
- max: 22.0
-mand: 21.1
15
Q
what is the average root length for canines
A
- max: 26.5
- mand:25.6
16
Q
what is the average root length for first premolar
A
- max: 20.6
- mand: 21.6
17
Q
what is the average root length for second premolar
A
- max: 21.5
- mand: 22.3
18
Q
what is the average length for the first molar
A
- max: 20.8
- mand: 21.0
19
Q
what is the average root length for the second molar
A
- max: 20.0
- mand: 19.8
20
Q
what is the usual number of roots and canals for max incisors
A
1 and 1
21
Q
what is the usual number of roots and canals for max canines
A
1 and 1
22
Q
what is the usual number of roots and canals for max first premolars
A
2 and 2
23
Q
what is the usual number of roots and canals for max second premolars
A
1 or 2 and 1 or 2
24
Q
what is the usual number of roots and canals for max molars
A
3 and 3 or 4
25
what is the usual number of roots and canals for mand incisors
1 and 1 or 2
26
what is the usual number of roots and canals for mand canines
1 and 1
27
what is the usual number of roots and canals for mand premolars
1 and 1 or 2
28
what is the usual number of roots and canals for mand molars
2 and 3 or 4
29
why is the goal for the WL to be 1mm short of the canal exit
this places the WL in close proximity to the natural apical constrictin
30
what is the result if the WL is too short
the canal is not well cleaned
31
what is the result if the working length is too long
- BLOW OUT
- guaranteed incomplete compaction at the apex and an explosion of sealer in the PA tissues
32
where is the reliable reference point usually loated
- tip of incisal edge for anterior
- tip of cusp for which the canal is named
33
what is the next step after dx
access
34
access to the pulp chamber facilitates:
- locating the canals
- negotiating the canals
- gaining patency
- establishing working length
- maintaining apical constriction
- a good outcome
35
what problems can poor access cause
- you will not have a predictable result
- you will miss canals
- you will not be able to clean properly
- you will not be able to shape completely
- you will not be able to fill adequately
36
what is access
drilling a hole through coronal structure to gain entrance into the pulp chamber
37
what is the objective of access
- to create effective shape that is:
- smooth
- constantly tapering
- respecting the shape of the natural canal
- constricting near the terminus of the root
38
what is the Coke bottle effect
the canal is bigger than the cervical access at some more apical point in the canal
39
what are the requirements of access
- visibility of pulp chamber and all canal orifices from a single vantage point
- straight line access to mid root for instrument placement
- complete removal of pulpal roof and pulp horns
- avoidance of unnecessary weakening of tooth
40
what is "Draw"
visbility of pulp chamber and all canal orifices from a single vantage point
41
straight line access to mid root is required for:
instruments and obturating materials without regard to the long axis of the tooth
42
what is the dentin triangle
cross hatched area of secondary dentin that should be removed to create better access to mesial root
43
what do you use to remove the dentin triangle
a .25/.12 rotary file
44
what are the steps of access
- outline form - 2D surface shape
- coronal access- extending into pulp
- radicular access- adjustments to allow easy straight line entry to mid-root of each canal
45
what bur should you use for outline form in molars? PM?
- molars: #4
- premolars: #2
46
what else influences access besides ideal
canal anatomy and tooth damage can determine shape, size, and location of initial entry
47
what is coronal access for
to allow unobstructed visualization of the pulpal floor and ALL canal orifices from a single vantage point
48
what do you do in coronal access
- reach pulp at 7mm and mark bur
- extend bur within the outline form to remove pulpal roof
- do NOT touch pulpal floor with access bur
49
walls of the coronal access should:
DIVERGE to the occlusal
50
why should the walls of the coronal access should diverge to the occlusal
- better light
- better visualization
- your temporary restoration which is placed between visits will not be easily dislodged to leak and contaminate
51
what is the purpose of radicular access
to allow straight line access to midroot for shaping instruments and obturation materials to observe canal path- not the long axis of the tooth
52
what do you do in radicular access
- flare into canals to remove obstructions and make instrument placement simple and foolproof without looking
- facilitates crown- down procedure
53
hand files generally require____ strokes/file before going to the next larger size file
100
54
what is the access shape for the maxillary central incisor
triangular access from lingual about 3mm on each side
55
what is the shape of access for the maxillary lateral incisor
triangular/oval access
56
what is the shape of maxillary canine access
triangular/oval
57
what is the shape of the access for mandibular incisors
oval
58
what is the shape of the access for mandibular canines
oval
59
how does inadequate access compromise shaping
- induces unnecessary bending of file
- creates apical transportation of canal
60
what is the shape of access in maxillary first premolar
thin oval - width of #4 bur
61
what is the shape for access of maxillary second premolar
thin oval- width of #4
62
what is the shape for access of the mandibular first premolar
thin oval
63
what is the shape of access of the mandibular second premolar
thin oval
64
what is the shape of access of maxillary 1st molar
triangle- apex to palatal
65
what is the shape for access of the mandibular first molar
trapezoid
66
what is the shape for access of the mandibular 2nd molar
trapezoi/triangle
67
