Class II Restorations Flashcards
Caries on the axial wall does not indicate
cutting the entire axial wall toward the pulp. Only remove caries.
Caries on the pulpal floor may necessitate widening of the preparation to remove caries, but don’t
deepen the entire pulpal floor to the depth of the caries.
Use a round bur or spoon excavator to remove caries and accept an irregular pulpal floor.
If recurrent caries extends gingivally in the box area, it is permissible and preferable to have a
“box within a box” rather than deepening the entire box gingivally unless caries requires it.
Add a liner only to the
deepest parts of the preparation, closest to the pulp.
Keep the liner material away from the —.
margins
Liner materials: (2)
- Calcium hydroxide
* Resin Modified Glass Ionomer
• Calcium hydroxide (2)
- Brand names: Life, Dycal
* Use on deepest preps- pulp capping material
• Resin Modified Glass Ionomer (3)
- Brand name: Vitrebond
- Light cured
- Releases fluoride over time
Why not have the entire floor of the restoration covered by calcium hydroxide?
CaOH is too soft to support the restoration.
If the material is hard when set (such as glass ionomer) the entire pulpal floor can be covered material, but the material must rest on a
tripod of dentin.
A Class II amalgam preparation has an
open side on the interproximal
Class II prep requires something to complete the box so that an amalgam can be placed:
A matrix band of some type is required to address this problem
The Functions of a Good Matrix Band: (5)
- 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 and allow for removal without breaking a partially set amalgam.
Spindle—
a Screw that is Used to Hold the Ends of the Matrix Band Securely in the Slot Vise
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
skipped
Pedo. Band—
Box of Normal Depth Gingivally
skipped
Pedo. Band—
Box of Deep Depth Gingivally
skipped
Adult Band–
Box of Deep Depth Gingivally
skipped
Adult Band—
Box of Normal Depth Gingivally
Inserting Band into the Tofflemire Retainer (4)
- Turn the inner nut counterclockwise until slot vice is about 1⁄4 inch from the guide channels.
- Hold inner nut and turn the outer nut counterclockwise until the pointed end of the spindle is free of the slot in the slot vice.
- Double the band back on itself, forming a loop.
- Insert into the slot vice, and direct it through one of the three guide channels. Tighten spindle.
Wider Opening in the Loop is Toward the — of the Tooth
Occlusal
Slot in Slot Vice is Toward the — of the Tooth
Gingival
Installing the Tofflemire Band on the Tooth—Three Possibilities
Choice 1:
Retainer on the Buccal Side, Band Emerges From One of the Side Guide Channels . By Far, the Most Common.
Choice 2:
Retainer on the Lingual Side; Requires use of a Contra-Angle Retainer. Useful with missing Buccal Tooth Structure.
Choice 3:
The Band Emerges Through the Middle Channel, Straight out the End of the Retainer. The Retainer Is on the Lingual of the Tooth. This Is Useful When There is Missing Buccal Structure, and Will Probably Be Used More in the Maxilla than in the Mandible because of the tongue