Class II review Flashcards
CLASS II COMPOSITE RESTORATION
PLACEMENT
* Foundations are the same as for amalgam restoration
* Additional steps to prepare tooth for bonding
(4)
- Etch (and rinse), Bond Agent placement (gentle dry, light cure), composite placed
incrementally, light cure each increment
CLASS II COMPOSITE RESTORATION
PLACEMENT
* More challenging to establish good contact
- Composite does not displace the matrix band like amalgam
- Shrinkage occurs as you light cure
- Different type of matrix may help counteract this issue
ETCH- Complete vs. Selective
* 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- Complete vs. Selective
* 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
Wash and dry enamel thoroughly
* Rinse and dry thoroughly.
(2)
- Be sure to dry on both sides of the matrix band and around the proximating teeth. Check for the whitish 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 dentin is contaminated with saliva then wash, dry apply bonding/primer agent, cure and continue.
Do not desiccate the dentin
This results in …
* Optional:
collapse of collagen layer (more on that later) and reduced bond strengths
- Place a cotton pellet over the dentin to avoid desiccating it
Apply Bond Agent
- Always read directions!
- Apply bond agent
- Gently push bond agent into tooth
- Brush on THIN layer
- Avoid letting bonding agent pool in your prep
- Gently blow air
- Thins bond agent
- evaporates solvent
- usually acetone, ethanol, or water
- Cure 20 seconds
- refer to your light’s guidelines
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
(3)
- Most important increment at gingival wall
- May use flowable composite here
- “layering” technique
- Make sure it is adequately cured
Add additional increments. The increments should not exceed
2 mm.
This method of placement minimizes stresses placed on the material and on the tooth due to —.
This may be a factor in —
polymerization shrinkage
postoperative sensitivity
Establishing interproximal contact
(3)
- 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
* Finish as well as possible BEFORE curing!
* Must work quickly
- Form the outer incline of the marginal ridge
- MARGINAL RIDGE SHOULD BE ROUNDED
- Not flat
- Flat shreds floss
Forming anatomy in composite is more like waxing lab than amalgam
* 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
- This cures the areas that were covered by the opaque matrix band
ways voids are created
(2)
- Composite can stick to an instrument and upon pulling back, a void is
created - When injecting the material, lifting the syringe may cause tug back and
a void is created
Consider using — composite in the box if you can’t place
composite without creating a void
flowable
Finishing and Polishing Composite
* These steps:
(4)
- Removes the oxygen inhibited layer
- Establishes anatomy/final shape
- Ensures a smooth surface
- EXTREMELY IMPORTANT IN COMPOSITE
- Major difference between amalgam and composite
Finishing composite
instruments (3)
Plastic/composite instrument
Optrasculpt
* Esthetic Trimming Carbides
Esthetic Trimming Carbides
(3)
- Use to finish and refine surface PRIOR to polishing
- High speed handpiece
- NOT at full power
- Use light, brushlike, sweeping motion with bur
Finishing composite
Proximal walls
discs (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
* 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
- marginal ridge height should be even
- Check occlusion with articulating paper
- Make sure there are no occlusal prematurities
- If there are, remove with finishing carbide
- Assess contact with floss
Polishing composite
(2)
Polishing composite
* 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:
(2)
- INCREASES LONGEVITY OF RESTORATIONS
- Improved marginal integrity
- Plaque resistant surface
- Improves esthetics
- Improved contours
- Undetectable margins
- Healthier gingiva
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.
CONSIDERATIONS FOR DEEPER
LESIONS
(3)
- Liners, sealers, and bases under amalgam
Liners, sealers, bases NOT NECESSARY for every preparation
UMKC uses
ADMIXED alloy (Dispersalloy)
no sealer nor liner is necessary (2)
Preparations ideal, OR deeper than normal, BUT with 1.0-2.0mm dentin
between pulp and restorative material
Preparations deeper than normal with LESS THAN 1.0mm dentin
between the pulp and the restorative material= use
RMGI liner
* Resin Modified Glass Ionomer
* Thermal insulator
Preparations with LESS THAN 0.5mm of dentin between the pulp and
restorative material= use
thin layer of calcium hydroxide followed by
a later of RMGI
Preparations with a direct pulp exposure on vital pulp=
0.5mm thick
calcium hydroxide layer followed by layer of RMGI
The — is an
extremely sensitive part
of the tooth. This is
where enamel and dentin
meet.
dentino-enamel
junction (DEJ)
Hydrodynamic theory of pain
transmission
(3)
- (most accepted theory of pain transmission).
- Dentinal tubules are filled with odontoblastic processes and wrapped in afferent nerves and dentinal fluid.
- When enamel or cementum is removed during cavity preparation, the external seal of dentin is lost, which allows small fluid movements in the tubules. This movement causes distortions in the afferent nerve endings, hence, pain.
Hydrostatic pressure changes within the tubules caused by external stimuli (eg., Temperature change, high speed handpiece, air drying, osmotic changes from various chemicals, caries, etc.) can cause
pain to the pulp through fluid movement within the tubules.
Air-water spray should be used whenever cutting
with high-speed handpieces to avoid
heat build up
and the destruction of the odontoblastic processes in
the dentin (dead tracts).
Dentin should not be — by air blasts, as this
could cause aspiration of odontoblasts into tubules.
dehydrated
Dentin should not be — by air blasts, as this
could cause aspiration of odontoblasts into tubules.
dehydrated