Class II Restorations; Caries Removal Considerations; Special Prep designs Flashcards
Caries on the axial wall does not indicate
cutting the entire axial wall toward the pulp.
Only _____ ______ .
remove caries
don’t deepen the entire pulpal floor to the depth of the caries. Use a _____ bur or
spoon excavator to remove caries and accept
an irregular pulpal floor.
round
If recurrent caries extends gingivally in the box
area, it is permissible and preferable to have a “____ ____ _ _____” rather than deepening the
entire box gingivally unless caries requires it.
“box within a box”
Add a calcium hydroxide liner only to the \_\_\_\_\_\_\_ parts of the preparation, closest to the pulp. Keep the calcium hydroxide away from the margins.
deepest
Restoration Should be Supported by at
Least a Tripod of_____ Structure
Natural
CaOH bases are too_____ to
support the restoration.
soft
- Has enough rigidity to resist too much deformation by packing forces or wedging,but is slightly burnishable and displacable (in order to get good contact with the adjacent
tooth). Can’t be too stiff or thick. - Assists in establishing proper anatomical
contour. Again, can’t be too stiff or thick. - Must prevent excess amalgam from being
expressed at the gingival margin as much as
possible, so as not to get a gingival overhang
that will trap plaque and irritate the gingivae. - Must be convenient to install
- Must be easy to remove. It must allow
removal without breaking a partially set
amalgam.
Functions of a Good Matrix Band System
The most common matrix band system
The Universal (Tofflemire) Matrix—
Diagonal Slot Vice
Spindle—a Screw that is
Used to Hold the Ends
of the Matrix Band
Securely in the Slot Vise
Guide Channels
(Three Choices)
The Inner Nut—used
to adjust the size of
the matrix band loop
The Outer Nut—Tightens
Band and Positions it
Within the Slot Vise
Parts of the Tofflemire Retainer
Wider Opening in the Loop is Toward the____ of the Tooth
Occlusal
Slot in Slot Vice is Toward the_____ of the Tooth
Gingival
What is the most common positioning of the Tofflemire Band on tooth??
Retainer on the Buccal Side, Band
Emerges From One of the Side Guide
Channels .
Band Positioning:
The Band Emerges Through the Middle Channel, Straight out the End of the Retainer
Useful When There is Missing Buccal Structure, and Will Probably Be Used More in the Maxilla than in the Mandible because of the tongue
A band with an apron is used when ?
the band won’t go far
enough apically to close
the gingival margin in a
deep box
- Choose a wedge of the proper shape and size
- Do not allow the wedge to force the band into the
box, into areas that should be filled with amalgam.
3. If the preparation extends far gingivally, the band may want to “jump up” on to the ledge of the gingival floor. Use a Hollenback carver to support the band and allow it to seat far enough gingivally for wedging and a good seal.
4. In the event of gingival recession and a proximal box of moderate depth, double wedging can be done in a vertical, “stacked” fashion to close the gingival margin.
5. In the event of an especially wide interproximal space and a gingivally deep box, double wedging can be done horizontally from the facial and the lingual.
- Interproximal fluting (root concavity) at
margin - When no standard wedge form will close the
gingival margin without distorting the band,
use a bur or sharp blade and reshape the
wedge until it works. - In an especially large space, a custom wedge
can be carved from a piece of a tongue blade.
Special
Considerations When Wedging
