6. Class II Amalgam Preparation Flashcards Preview

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Flashcards in 6. Class II Amalgam Preparation Deck (23)
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1
Q

Class II Lesion

Found on the ____ surfaces of ____ teeth (sides of teeth)

____ surface cavity

Found mesially and distally usually just below the ____
(where the teeth touch each other)

A

proximal
posterior
smooth
contact points

2
Q
Classification by Surface
   \_\_\_\_ surface
   Take the name of
both surfaces    Examples
  Mesio-occlusal (MO)
  Disto-occlusal (DO)

Classification by Complexity
____
Prepared cavities
that involve ____ tooth surfaces

A

two
compound
two

3
Q

Begins with a broad decalcification of enamel
See a ____ of decay progressing through enamel towards dentin on an x-ray
At DEJ, decay spreads out then forms a ____ of decay towards the pulp
Cones of decay are ____ to ____ at DEJ

Once the lesion reaches dentin, it flares at the DEJ
Proximal surface is still intact
Only see lesion on an ____
Eventually the surface breaks down and explorer can penetrate
Then, the lesion progresses toward pulp

A
cone
cone
apex
base
x-ray
4
Q

Clinical appearance
May not have a clincal appearance, or
____ over the marginal ridge if the cavity has progressed and undermined the enamel

A

opacity

5
Q
Noncavitated:
   \_\_\_\_ intact
   \_\_\_\_ of proximal surface may
be present
Superficial radiolucency may be present
   Marginal ridge is not \_\_\_\_
■  Cavitated:
   Surface broken, detected
visually or possibly tactilely    Marginal ridge may be
discolored /shadow
   \_\_\_\_ area in dentin on
transillumination
   Radiolucency is present
beyond the \_\_\_\_
A
surface
opacity
discolored
opaque
DEJ
6
Q

Class II Preparation
Considerations:
An extension of Class I
Occlusal surface is normally included Convenience form
Extension for prevention
Lesion is removed by creating a box shaped preparation around the caries

Anatomic Considerations: Some areas are not included in the preparation:
Intact ____ on maxillary molars are not normally included in the preparation outline
This is avoided because the ____ of the crown is significantly greater when this ridge is left intact

A

oblique ridges

strength

7
Q

____ in the mandibular first premolars do not usually have a deep connecting fissure between the mesial and distal pits and not normally included in the preparation to avoid weakening the small lingual cusp

Some cases may be limited to a proximal
box preparation only – ____ PREP (usually for ____ preparations)

A

transverse
slot
composite

8
Q

B and G: ____ to occlusal table and ____ to long axis of the tooth)
P and A: ____ external surface and pulpal chamber and ____ to long axis of the tooth

A

parallel
perpendicular
parallel
perpendicular

9
Q

Class II Outline Forms
Man First Premolar

When preparing, tilt bur slightly ____ to establish correct pulpal wall direction
Pulpal wall will slope ____
Gingival wall is ____ to long axis of tooth

A

lingually
occlusally
perpendicular

10
Q

Class II Outline Forms
Max/Man Premolars
Finished outline form including the ____, lingual extension (mand ____) , proximal box and ____ curve

Man Molars
Finished outline form including the buccal and lingual extensions, proximal box reverse S curve
No ____

A

dovetail
2nd
reverse S
dovetail

11
Q

Class II Outline Forms
Max Molars
Due to oblique ridge
MO: Only mesial portion of occlusal surface is included
DO: Only distal portion of the tooth is involved

If oblique ridge is undermined, then ____

If distal caries and undermined oblique ridge, then ____ cavity will be prepared

If the oblique ridge is undermined, and the lingual groove has caries, then continue through ____ and ____

A

continue
MOD
ridge
groove

12
Q

Principles of cavity design and preparation
External Outline Form Part I - Occlusal As in Class I Outline:
All carious ____
All ____ enamel
All ____ enamel
Molar Occlusal Outline: Extend into the major developmental grooves ____mm

A

pits and fissures
decalcified
undermined
1

13
Q

External Outline Form - Occlusal
Try to keep isthmus width equal to or less than ____ the distance between the cuspal line angles

Occlusal Preparation
As in Class I Outline: Use 330 bur
____ mm into dentin (____ in the shallowest area)
Pulpal floor flat, smooth, and level

A

1/4

  1. 5
  2. 5
14
Q

Principles of cavity design and preparation

External Outline Form Part II - Proximal
Opening is extended buccolingually and gingivally with 330 bur. As the box area deepens beyond depth of 330 bur, switch to the 245 bur.
____ motion
Proximal portion will be wider buccolingually at the ____ level and narrower at occlusal portion (retention)

A wooden wedge can be placed gingival to contact area:
Slightly opens the interproximal space and aids in preventing damage to the adjacent teeth
Aids in preventing injury to soft tissues *Also can place a matix band interproximally

A

pendulum

gingival

15
Q

Proximal box placement and size is dictated by the ____

Clearance between the teeth is ____ mm, measured with the tip of the explorer along the entire buccal, lingual and gingival walls of the box

A

contact

0.5

16
Q

Principles of cavity design and preparation
Outline Form - Proximal
May use a fissure 245 or 55 bur
Clinically, go gingivally until you break contact
Want at least ____mm long axial wall occlusogingivally

A

1

17
Q

Principles of cavity design and preparation

External Outline Form Part III – S/Reverse S
Blend the occlusal outline and the proximal box outline
There is a very ____ angle at the junction
of the occlusal outline and proximal box
This is part of the outline but done to the outline to satisfy ____

Resistance Form – S/Reverse S
Want proper blending of box with occlusal part
Place a S-curve or reverse S where ever indicated
Besides blending Occlusal and Proximal outline forms, it allows “____” 90 degree angle of proximal walls

A

acute
resistance form
butt joint

18
Q

Principles of cavity design and preparation

What determines where the reverse curve will be? PROXIMAL ____
It is often easy to break contact ____(embrasure spaces are larger) and a butt joint will be achieved without a reverse S curve
Most often ____

A

contact
lingually
buccally

19
Q

Principles of cavity design and preparation
Internal Outline Form and Resistance Form

Pulpal wall

  • developed ____ to long axis of tooth
  • depth just into dentin
  • perfectly flat
  • where it joins axial wall, forms sharp axiopulpal line angle

Refinement
____ the axiopulpal line angle with ginigval margin trimmer
Plane gingival wall with gingival margin trimmer to remove unsupported enamel rods
Use a 169 or 170 bur to flare the occlusal wall bordering the marginal ridge by ____ degrees

A

perpendicular
round
3

20
Q

Principles of cavity design and preparation
Internal Outline Form and Resistance Form

Gingival Wall
____ to long axis of tooth
____ mm in width M-D for premolars
____ mm in width M-D for molars

The Axial wall
____ with long axis of the tooth – Vertical wall
At least ____ mm deep O/G and M/D
Curves ____, parallel with the proximal surface of the tooth
The finished axial wall is just inside the____ (M-D orientation)

A
perpendicular
1.0
1.5
parallel
1
faciolingually
DEJ
21
Q

Principles of cavity design and preparation
Internal Outline Form and Retention Form

Convergent walls
Prevents occlusal ____ of amalgam

Dovetail on premolars:
Occlusal portion is widened in the opposing fossa toward the facial to include the ____ of the triangular fossa
Slightly ____ than the isthmus
Prevents proximal ____ of amalgam

Extensions into grooves on molars – no ____ needed

A
dislodgement
fissures
wider
dislodgement
dovetail
22
Q

Principles of cavity design and preparation

Finishing margins
The cavity preparation is now refined with hand instruments
Facial and lingual walls form a 90 angle with the proximal surface of the tooth – ____ joint
Finish lateral proximal walls into smooth, flat surfaces with hatchets
Proximal facial and lingual walls are smoothed to blend with the facial and lingual walls of occlusal preparation

The Gingivocavosurface angle is planed to remove ____ enamel
The Axiopulpal line angle is smoothed
The Gingivocavosurface angle is ____ slightly to blend with facial
and lingual walls

A

butt
unsupported
rounded

23
Q

20 DO

Preparations Completed in the GRD I Laboratory

Isthmus and lingual
extension is measured with the large end of the 1P condenser (isthmus – slightly ____, extension - ____)
Axial wall is ____ mm deep O/G
Gingival wall is ____ mm in width mesiodistally, and measured with the small hatchet

Isthmus is measured with the large end of the 1P condenser
(slightly ____)
Extension in Buccal and Lingual grooves ____ mm measured with the large end of the 1P condenser (____)
Axial wall is ____ mm deep O/G
Gingival wall is ____ mm in width M-D, and measured with the large hatchet

A

loose
snug
1.5
1

loose
1
snug
1
1.5