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
If the band won’t go far enough apically to close the gingival margin in a deep box, use a
band that has an
“apron”
If the “apron” in the other interproximal space keeps the band from seating far enough,
use scissors and trim the unwanted “apron” away.
If the band needs to flare out more to restore the rounded convexity of the original tooth contact,
remove the band assembly and use a ball burnisher and egg burnisher with the band resting on a paper pad.
Take care not to trap the rubber dam material between the
Tofflemire band and the tooth at the gingival margin.
Take care not to trap the rubber dam material between the Tofflemire band and the tooth at the gingival margin.
If this happens, partially remove the band and retainer,
use your fingers to stretch the rubber dam septum and pull it gingivally, and then reseat the assembly.
Sometimes, gingival tissue will get caught between the matrix band and the gingival margin of the preparation:
If this happens,
move the matrix band slightly in an occlusal direction, place a Hollenback carver between the matrix band and the tissue, deflecting the tissue, and reseat the band:
To close the margin at the gingival of the box and prevent an overhang of amalgam,
place a wooden wedge with the cotton pliers. Place the wedge through the more open of the embrasures (almost always the lingual).
Installing the Tofflemire Band—Special Considerations When Wedging (7)
- 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.
- 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. - 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. - 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.
- Interproximal fluting (root concavity) at margin
- When no standard wedge form will close the gingival margin without distorWng the band, use a bur or sharp blade and reshape the wedge unWl it works.
Insert wedge at an angle through the
more open embrasure
Obtaining a Good Contact (5)
- Loosen the band a quarter turn after wedging
- Burnish the band against the proximal surface of the adjacent tooth.
- Scrape with an explorer along the tooth-metal interface at the gingival margin to remove any tissue or debris in this area. Flush and dry the preparation well.
- If the band is still not against the adjacent tooth, loosen the retainer more while the band is tightly wedged at the gingival. Burnish again against the adjacent tooth and recheck that the wedge is tight.
- Pack amalgam hard against the matrix band in the contact area.
ENSURING THAT YOUR (2) ARE PLACED PROPERLY WILL RESULT IN A MUCH BETTER RESTORATION AND FEWER ADJUSTMENTS
MATRIX AND WEDGE
The matrix band can contribute to proper or improper contours, but since it is relatively soft, it can be
pushed in appropriate directions while packing amalgam to develop proper contours & line angles.
Placing the Amalgam
- Burnish the matrix band against the adjacent tooth and reconfirm the Wghtness of the wedge:
- Loosen the inner nut 1⁄4 turn to assist in getting good contact. Mix the amalgam, dispense in the amalgam well, and pick up with the amalgam carrier.
- Unload only one carrier-full into a box at a time. Unload a carrier-full into the occlusal part of the prep., but condense the box first.
- Use the Hollenback condenser to pack FIRMLY into all internal line angles, in a stepwise fashion.
- Good condensation is very important
- Finish packing the occlusal part of the prep. until you have filled about 1 mm. beyond the margins.
- Try to complete the condensation in three to four minutes. The side of the Hollenback condenser or the large ball burnisher can be used to do a pre- carve burnishing of the amalgam. This helps eliminate voids.
- Use the explorer at a 45 ̊angle to begin to define the occlusal embrasure by trimming away the amalgam that runs up onto the matrix band.
- Let the inclines of the tooth guide the side of the hollenback carver while your knowledge of tooth anatomy guides the tip, forming grooves.
- THE MARGINAL RIDGE should be carved at the same height as the adjacent marginal ridge. It should have a straight secWon, perpendicular to the long axis of the tooth, with a triangular inclined plane descending from the ridge crest into the pit.
- Redefine the occlusal embrasure with the explorer one more time, and REMOVE THE WEDGE.
- Loosen the inner and outer nuts and REMOVE THE TOFFLEMIRE RETAINER FROM THE BAND. If the retainer was installed correctly, it will withdraw occlusally from the band.
- On a two-surface amalgam, REMOVE THE BAND first on the non-restored surface, then—next to the new amalgam– by sliding the band slightly horizontally, and then in an oblique, occlusal direction, drawing it out. The lateral component in this movement helps prevent marginal ridge fracture. Don’t draw straight vertically.
- Use the Hollenback carver to CARVE EXCESS AMALGAM OFF THE BUCCAL AND LINGUAL WALLS OF THE BOX. Drag the carver across these margins going gingivally, to avoid breaking off the corner of the marginal ridge. Carve embrasures to normal form.
- CARVE AWAY THE GINGIVAL MARGINAL EXCESS ON THE BOX. This can be done with three different instruments:
- REMOVE THE RUBBER DAM by snipping the septa between the teeth. Don’t try to pull this off past a freshly placed amalgam.
- MAKE SURE THE MARGINAL RIDGE IS EQUAL IN HEIGHT TO THAT OF THE ADJACENT TOOTH.
Occlusion is challenging to assess using our typodonts’ intercuspation. Compare to adjacent teeth anatomy instead. - ADJUST OCCLUSION. In a live patient, mark occlusion with articulating paper, closing in maximum intercuspation, and going into right and left lateral excursion as well.
- Eliminate inclined plane contacts first. Try to preserve stops for the opposing cusps that will put long axis forces on the teeth (marginal ridge crest, bottom of the fossa, for example).
- SMOOTH SURFACES AND BOTTOMS OF GROOVES gently with beavertail burnisher.
- ASSESS THE INTERPROXIMAL CONTACT with the floss (hold flat surface of floss vertically when passing it through). Also, dry the contact area, and look through from the facial or lingual to be sure the contact is closed.
- Use the Hollenback condenser to pack FIRMLY into all internal line angles, in a stepwise fashion. (3)
- In the box, pack firmly, at an angle, into the buccal-gingival and lingual-gingival line angles, and against all other margin areas especially. Use a stepwise, “press and wiggle” technique.
- Be especially aware of the corners of the box, where it is easy to get voids.
- Condense against the contact area on the band. Voids are often the result of placing too much amalgam in the box before condensing the first time.
Loosen the inner and outer nuts and REMOVE THE TOFFLEMIRE RETAINER FROM THE BAND. If the retainer was installed correctly, it will withdraw — from the band.
occlusally
On a two-surface amalgam, REMOVE THE BAND first on the non-restored surface, then—next to the new amalgam– by sliding the band slightly (3) direction, drawing it out. The lateral component in this movement helps prevent marginal ridge fracture. Don’t draw straight —.
horizontally, and then in an oblique, occlusal
vertically
Use the Hollenback carver to CARVE EXCESS AMALGAM OFF THE BUCCAL AND LINGUAL WALLS OF THE BOX. Drag the carver across these margins going —, to avoid breaking off the corner of the marginal ridge. Carve embrasures to normal form.
gingivally
CARVE AWAY THE GINGIVAL MARGINAL EXCESS ON THE BOX. This can be done with three different instruments: (2 methods)
Method 1: the Hollenback Carver Held Obliquely, and Drawn Laterally or Occlusally
Method 2: the Wiland Carver, or a 34-35 Jaquette Scaler, Drawn Laterally or Occlusally
Patients have a way of closing too hard and crushing amalgams. Avoid saying, “Close and move around with your jaw.” Say,
“Now, VERY GENTLY, close…..” They can put a little more force later, as you fine tune the adjustment.
The most effective instrument for adjusting occlusion on a partially set amalgam is the
discoid carver .
This will help develop a round bottomed cusp seat for long axis forces. You can redefine groove anatomy with the Hollenback or cleoid carver after final occlusal adjustment.
Don’t overburnish, trying to polish the amalgam with the burnisher. It only shines because you have brought excess mercury to the surface, which may
weaken the amalgam.
Wipe with wet cooon pellet, leaving a smooth, maoe finish.
A triangular inclined plane descends from the ridge crest into the pit, which is further apical than ridge crest. This deflects
food toward the occlusal table of the tooth.
INTERPROXIMAL VIEW: Marginal ridge has a straight area that is perpendicular to the long axis of the tooth, so a cusp striking there can put — — forces on the tooth root in maximum intercuspa\on.
long axis
The central groove crosses the marginal ridge, making ridge “V-shaped” when seen from interproximal. No area of the ridge is perpendicular to long axis of tooth, so cusp is “locked in” and
forces in M.I. are not down long axis of tooth.
Pit anatomy is indistinct, and bottom of pit is not further apical than the ridge crest. This may create —, or may deflect food toward the interproximal.
inclined- plane occlusal contact
Marginal Ridge is Carved
Higher than, or Lower than, Adjacent Ridge Crest. This
can cause
food impaction
Marginal Ridge is Carved
Higher than, or Lower than, Adjacent Ridge Crest. This
can cause food impaction.
It can also create occlusal contacts that would
deflect the mandible (or the tooth, eventually) in the M. I. position, creating occlusal problems or an open contact.
Try, if possible, to carve anatomy so that the occlusal stop in maximum intercuspation is in the
bottom of the fossa. This will put long axis forces on the teeth
If you carve grooves so deep that no stop is created in maximum intercuspation, the teeth may later — to re- achieve contact, but the forces may not be down the
erupt
long axis of the teeth if that happens
CLASS II COMPOSITE RESTORATION PLACEMENT (3)
- Foundations are the same as for amalgam restoration
- Additional steps to prepare tooth for bonding
- More challenging to establish good contact
Additional steps to prepare tooth for bonding
Etch (and rinse), Bond Agent placement (gentle dry, light cure), composite placed incrementally, light cure each increment
More challenging to establish good contact (3)
- Composite does not displace the matrix band like amalgam
- Shrinkage occurs as you light cure
- Different type of matrix may help counteract this issue
DO NOT USE CLEAR MATRIX BAND. why not? (4)
- Too much flash
- Poor contours
- Reservoir for moisture
- Overall terrible
— can also work for composite restora@ons
Tofflemire
Sec@onal matrix will likely result in improved (2)
contour and contact
The matrix band must be contacting the proximating tooth. (3)
◦ Place wedge appropriately (same as for amalgam)
◦ Press band against proximal tooth with instrument
(◦ Burnish well against adjacent tooth)
◦ Cure first increment to ensure good contact
(◦ Be careful not to lock your instrument in composite!)
Sectional Matrix (4)
Step 1: Use provided tweezers to place wedge or WedgeGuard PRIOR TO PREPARATION Step 2: ARer preparing tooth, remove shield porKon of WedgeGuard if applicable (use provided tweezers) Step 3: Place secKonal matrix band using provided tweezers Step 4: Place Ring on top of wedge. The wedge will fit between indentaKons on bo\om of ring.
ETCH
Complete (5)
◦ Place etch on enamel first, followed by dentin
◦ ETCH ENAMEL 20-30 SECONDS
◦ ETCH DENTIN 15-20 SECONDS
◦ Rinse and gently air dry
◦ Typically only done with total-etch and universal bond agents
ETCH
Selective (5)
◦ Etch enamel only
◦ 20-30 seconds
◦ Rinse and air dry
◦ Can only be done with certain bond agents
◦ Universal(what we use in clinic and lab) and Self-etch
types
Rinse and dry thoroughly. (2)
◦ Be sure to dry on both sides of the matrix band and around the proximaGng teeth. Check for the whiKsh etched enamel surface. Re-apply the etchant if there is not clear evidence of etched enamel.
◦ It may be appropriate to re-etch for 10 seconds if the enamel or denGn is contaminated with saliva then wash, dry apply bonding/primer agent, cure and conGnue.
Do not desiccate the dentin
This results in collapse of collagen layer (more on that later) and reduced bond strengths
Optional:
◦ Place a cotton pellet over the dentin to avoid desiccating it
Apply bond agent (2)
◦ Gently push bond agent into tooth
◦ Brush on THIN layer
Avoid leQng bonding agent – in your prep
pool
Gently blow air (3)
◦ Thins bond agent
◦ evaporates solvent
◦ usually acetone, ethanol, or water
Cure – seconds
◦ refer to your light’s guidelines
20
Oxygen Inhibited Layer
The sticky uncured layer left on the surface
◦ Oxygen in air interferes with polymerization on surface of composite
Oxygen Inhibited Layer facilitates
bonding to the next layer added
Finishing can
remove oxygen inhibited layer
◦ Can also gunk up your burs
Place composite incrementally (3)
Place the first layer of composite resin in the proximal box to a depth of about 1mm
◦ Some use flowable for first layer
◦ Can leave flowable uncured and place regular composite on top
Adapt well into the preparation and against the matrix band with a small condenser
Cure 20 seconds
Place composite incrementally (3)
Place the first layer of composite resin in the proximal box to a depth of about 1mm
◦ Some use flowable for first layer
◦ Can leave flowable uncured and place regular composite on top
Adapt well into the preparation and against the matrix band with a small condenser
Cure 20 seconds
first increment:
Most important increment at — wall
gingival
First Increment
May use — composite here
◦ “layering” technique
Make sure it is adequately cured
flowable
Add additional increments. The increments should not exceed – mm.
2
add additional increments. this method of placement minimizes stresses placed on the material and on the tooth due to
polymerization shrinkage
this may be a factor in postoperative sensitivity
build up in —, do not —
increments
bulk flow
Establishing interproximal contact
Press the matrix band firmly against the marginal ridge of the proximating tooth with the side of a metal condenser while curing the initial increments.
◦ This helps to obtain a good contact. Palodent Plus shapes this for you
Form the final anatomy using plastic instrument (2)
◦ Finish as well as possible BEFORE curing!
◦ Must work quickly
Form the outer incline of the marginal ridge (3)
◦ MARGINAL RIDGE SHOULD BE ROUNDED
◦ Not flat
◦ Flat shreds floss
Forming anatomy in composite is more like waxing lab than amalgam (2)
◦ Except your in a slight time crunch
◦ Overhead lights will cause composite to polymerize
Final Cure (3)
Remove the matrix
Cure the restoration from the buccal 20* sec
Cure the restoration from the lingual 20* sec
◦ Thiscurestheareasthatwerecoveredbytheopaquematrixband
New things to consider with composite (4)
Interproximal contacts
Voids
Light
Polymerization stress
Composite can sWck to an instrument and upon pulling back, a — is created
void
When injecWng the material, liring the syringe may cause tug back and a — is created
void
Consider using — composite in the box if you can’t place composite without creating a void
flowable
Be careful to avoid light shining directly on the resin while you work (2)
◦ Overhead light AND loupes light
◦ It can prematurely cure your resin.
When curing, make sure the orange protective light is blocking
your view of the cure
Finishing and Polishing Composite
These steps: (5)
◦ Removes the oxygen inhibited layer ◦ Establishes anatomy/final shape ◦ Ensures a smooth surface ◦ EXTREMELY IMPORTANT IN COMPOSITE ◦ Major difference between amalgam and composite
Work on shaping composite with plastic instrument
◦ Rather than —
bur
Finishing composite (3)
Plastic/composite instrument
Optrasculpt
Esthetic Trimming Carbides
Esthetic Trimming Carbides (4)
◦ Use to finish and refine surface PRIOR to polishing
◦ High speed handpiece
◦ NOT at full power
◦ Use light, brushlike, sweeping moWon with bur
Proximal walls (2)
- Can use discs to finish, if necessary
* Discs available in lab are very abrasive
Only after properly finishing composite restoration can
you polish!
• If left rough or scratchy, the polishing paste will stick in irregularities and
make appearance worse
We use points and discs that are impregnated with polishing paste (2)
• Used in latch-type head of electric handpiece on polishing speed
• Get them slightly wet and use them to polish your restorations to a high
luster
Checking occlusion and contact (4)
- Remove rubber dam
- Compare occlusion to adjacent tooth
- Check occlusion with articulating paper
- Assess contact with floss
Compare occlusion to adjacent tooth (1)
• marginal ridge height should be even
Check occlusion with articulating paper (2)
- Make sure there are no occlusal prematurities
* If there are, remove with finishing carbide
Polishing composite (2)
- Polishing of composite should be completed on the SAME DAY as it is placed
- Polishing must be completed after properly finishing composite
Proper finishing and polishing:
• INCREASES LONGEVITY OF RESTORATIONS (2)
- Improved marginal integrity
* Plaque resistant surface
Proper finishing and polishing:
• Improves esthetics (2)
- Improved contours
- Undetectable margins
- Healthier gingiva
