Lecture 2: Cleaning & Shaping

Question 1

Determine what type of canal is seen below:

Answer 1

Type I

Question 2

Determine what type of canal is seen below:

Answer 2

Type II

Question 3

Determine what type of canal is seen below:

Answer 3

Type III

Question 4

Determine what type of canal is seen below:

Answer 4

Type IV

Question 5

What are the five principles to shaping?

Answer 5

1. a CONSTANTLY TAPERING FUNNEL from crown to WL
2. CURVES OF CANAL RESPECTED without transportation
3. Retention of the APICAL CONSTRICTION
4. ENLARGEMENT OF THE CANAL SYSTEM to create clean white fillings
5. ADEQUATE DEEP SPACE for proper obturation

Question 6

List the nine steps following proper access:

Answer 6

1. scouting (#10 hand file)
2. patency (#10 hand file)
3. working length (#15 hand file) TIGHT file
4. glide path (#15 hand file) LOOSE file

—ONLY HAND FILES TO THIS POINT—-

5. shaping of coronal 1/3 of canal (wave one gold)
6. shaping of middle 1/3 of canal (wave one gold)
7. perfecting straight-line-acess to mid-root (.25/.12)
8. shaping of apical 1/3 of canal (wave one gold)
9. final shaping objective (vortex blue)

Question 7

When using hand files after the shaping of the apical 1/3 of canal, this process is called:

Answer 7

SSB (serial step back)

Question 8

What file is used for scouting?

Answer 8

10

Question 9

What file is used to find patency?

Answer 9

10

Question 10

What motion is used during scouting?

Answer 10

watch winding

Question 11

The gentle, right & left rocking motion, which causes the instrument to cut while a light and inward pressure (straight arrow) keeps the file engaged and progressing towards the apex:

Answer 11

watch winding

Question 12

The canal is _____ when a #10 file goes slightly beyond the apex and 0.5mm into the PDL

Answer 12

Patency

Question 13

When watch-winding, how many degrees each way?

Answer 13

30 degrees

Question 14

The canal is _____ when a #10 file goes slightly beyond the canal exit (0.5mm) = long = into the PDL

Answer 14

Patent

Question 15

The ______ will help us located the canal exit clinically

Answer 15

apex locator

Question 16

Patency is maintained by:

Answer 16

recapitulation

Question 17

Patency is maintained by recapitulation which is:

Answer 17

irrigated and resisting patency after wave one with the #10 file

Question 18

When trying to obtain patency, if there is TIGHT resistance to apical advancement, you probably have:

Answer 18

small canal

Question 19

When trying to obtain patency, if there is LOOSE resistance to apical advancement, you probably have:

Answer 19

canal curvature

Question 20

All shaping is done at:

Answer 20

WL

Question 21

What is the reference point for anteriors?

Answer 21

incisal edge

Question 22

What is the reference point for posteriors?

Answer 22

Cusp for which canal is named

Question 23

On the apex locator what denotes patency?

Answer 23

single red line

Question 24

How do you tell if two canals converge or are simply two canals in close proximity?

Answer 24

The 2 file technique

Question 25

What is being described below? 1. establish working length of "each canal" separately 2. attempt to place 2 files to WL in each canal at the same time 3. If both go to working length this means you have two canals 4. If one goes to WL and the other is short, reverse the placement sequence and if one is still short this means you have a converging class II canals

Answer 25

2 file technique (to determine if there are two canals in close proximity or if canals converge)

Question 26

To determine if there are two canals in close proximity or if canals converge: If both files go to working length:

Answer 26

2 canals

Question 27

To determine if there are two canals in close proximity or if canals converge: Only one canal goes to WL:

Answer 27

canals converge to single apical exit

Question 28

You should create a smooth glide path only after:

Answer 28

WL is confirms with #15 hand file

Question 29

List the purposes of creating a smooth glide path: (3)

Answer 29

1. smooth curves and make sure no canal obstructions 2. create space for rotary instruments 3. to relive stress on tip of rotary file (minimize fracture risk)

Question 30

The glide path is created using:

Answer 30

Hand files (pre-curved to match or slightly exceed the curvature of the canal); watch-winding entry & pull strokes

Question 31

What motion do we use when using waveone gold to shape the canals?

Answer 31

Light "pecking" motion

Question 32

When do we perfect the straight-line access to mid-root?

Answer 32

following second 1/3 shaping with wave one

Question 33

What do we use to perfect straight-line access to mid-root?

Answer 33

.25/.12 Vortex orfice opener

Question 34

What files are used for the final shaping and smoothing of the canal?

Answer 34

Vortex blue files

Question 35

Radiographs will generally show ____ & ____ curves

Answer 35

mesial & distal

Question 36

____ & ____ curves will usually NOT be seen on the radiograph

Answer 36

facial & lingual

Question 37

A bulls eye indicates:

Answer 37

root tip severely turns to facial or lingual

Question 38

What can happen when we place a straight hand file in a curved canal?

Answer 38

Ledges & blockages

Question 39

A ledge can be the first step to _____ or ____

Answer 39

blockage or transportation (outside wall)

Question 40

____ of apex occurs within the root. This may also be called:

Answer 40

tranportation; zip

Question 41

If a zip occurs through the apex to the exterior of the root, we have an:

Answer 41

apical strip perforation

Question 42

Occurs when files used are either too large or too aggressively used for a small and thin walled canal:

Answer 42

strip perforation

Question 43

Strip perforations commonly occur on the distal or mesial root of ____ and MF of _____ & _____

Answer 43

lower molars; upper molars; 2-canal premolars