Transcript Amalgam Composite

RSD 810/814 2016 Spring
Last Session- Wrapping Up
C. Rodriguez D.M.D.
Summit
Sturdevant's
Composite
Advantages:
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esthetics
conservative to tooth structure
less complex preparation
insulating; having low thermal conductivity
universal usage
good retention due to bonding, relatively low microleakage, minimal
interfacial staining, increased strength of remaining tooth
repairable
Composite
Disadvantages:
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may have gap formation due to polymerization shrinkage
more difficult, time-consuming, and costly to place
more technique-sensitive due to need for isolation and proper
technique in etch, prime, and bond
may exhibit greater occlusal wear
higher linear coefficient of thermal expansion resulting in potential
marginal percolation if bonding technique is poor
Composite
Clinical indications:
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Class I, II, III, IV, V, and VI restorations
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Foundations or core buildups
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sealants and PRR
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esthetic enhancement procedures:
partial veneers
full veneers
tooth contour modifications
diastema closures
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cements
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temporary restorations
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periodontal splinting
Composite
Clinical contraindications:
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inability to isolate
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patients with heavy occlusion, bruxism
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restoration must provide all of tooth’s occlusal contact
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extension of restoration onto root surface
Clinical indication comparison of the two most commonly used
restorative operative materials:
Amalgam
Composite
Heavy occlusion
Root surface
Unable to isolate
Easy to fill, hard to prep
Cheap
Minor occlusion
Esthetic area
Isolate able
Easy to prep, hard to fill
Solvent patient
The primary objective of operative dentistry is to repair the
damage from dental caries or trauma while preserving the vitality
of the pulp.
The pulp should not be subjected to unnecessary abuse from poor
or careless operative procedures.
Isolation to prevent contamination
The use of water-coolant is critical
In order to better understand restorative operative
procedures, let us recall the caries process and
discuss everyday treatment modalities.
Necrotic dentin is recognized clinically as a wet, mushy, easily removable
mass.
This material is structureless or granular in histologic appearance and
contains masses of bacteria.
Removal of this material uncovers deeper infected dentin (turbid dentin),
which appears dry and leathery.
Leathery dentin is easily removed by hand instruments and flakes off in
layers parallel to the DEJ.
What you can leave
Dentin responds to the stimulus of its
first caries demineralization episode by
deposition of crystalline material in the
lumen of the tubules and the
intertubular dentin of affected dentin in
front of the advancing infected dentin
portion of the lesion. It is softer than
normal dentin.
Even when the lesion is limited to enamel, the
pulp can be shown to respond with
inflammatory cells
What you cannot leave
Dentin that has more mineral content than normal dentin is termed
sclerotic dentin. Sclerotic dentin formation occurs ahead of the
demineralization front of a slowly advancing lesion and may be seen
under an old restoration . It is usually shiny and darker in color but feels
hard to the explorer tip.
When sclerotic dentin is encountered, it represents the ideal final
excavation depth because it is a natural barrier that blocks the
penetration of toxins and acids.
*By contrast, normal, freshly cut dentin lacks a shiny, reflective surface
and allows some penetration from a sharp explorer tip.
In addition to the assault suffered from bacterial caries invasion, the pulp may
be irritated during or after operative procedures by:
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heat generated by rotary instruments
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some ingredients of various materials
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thermal changes conducted through restorative materials
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forces transmitted through materials to dentin
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galvanic shock
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ingress of noxious products and bacteria through microleakage
Liners or bases are used to protect the pulp or to aid in pulpal recovery or both.
Cavity Sealers
Provide a protective coating on freshly cut tooth structure (i.e.
seals the dentinal tubules) and is measured in microns (µm)
In years past Copalite Varnish was used under amalgam.
Currently UKCD recommends the use of Gluma to seal tubules
when a shallow amalgam restoration is planned. It may also be
utilized for some desensitizing procedures.
Rationale for the use of a dentinal disinfectant/sealer like Gluma.
Fig 5-1a Bacteria will penetrate the marginal
gap and dentinal tubules from the saliva,
which may cause pulpal irritation, pulpal
necrosis, or recurrent caries.
Fig 5-1b If a restoration is not well sealed,
fluid flows out of the dentinal tubules and
into the space between the restorative
material and the tooth surface (arrows). A
stimulus such as heat or cold causes a change
in the flow rate, which is interpreted by
The thickness of sealers is measured in microns. mechanoreceptors as pain.
Amalgambond is the bonding method of
choice under amalgam when isolation is
possible.
It is not required.
It should not be used instead of
conventional resistance and retention
forms.
Liners normal thickness < .5 mm
• Initial electrical insulation
• Some thermal protection
• May provide fluoride release
• Can adhere to tooth structure
• May be antibacterial in promoting pulpal health
Liners:
• CaOH
• Auto-cure
• Light-cured
• Problems with Dycal:
• It degrades over time creating a “trampoline effect”
• Traditional CaOH liners may continue to dissolve over time (due to
microleakage or dentinal fluid present) and can lose as much as 10-30
% of their original volume
• Light-cured CaOH (i.e. VLC Dycal) has overcome some of these
weaknesses but is not as effective in releasing ingredients.
Liner or Base (how thick is it, is it over Dycal?)
Place a glass ionomer liner such as Vitrebond or Fuji Lining LC
over Dycal. Why?
• Compressive strength of Dycal is very poor, allows for
condensation of amalgam.
• Glass ionomer liner will seal the margins around the Dycal
allowing for acid etching under composite.
Base: Normal thickness > .5mm
• Glass Ionomers*
• Two types: conventional (GI) and light-cured (RMGI)
• Two outstanding characteristics of all glass ionomers
 Fluoride release
• Anti-cariogenicity
• Mechanism: initial low pH, chemical bonding and the
release of the metal cation fluoride
Adhesion to enamel and dentin
• Reduces microleakage (physical exclusion)
• Eliminates the need for dentin bonding agents
* May be used in thin layer as a liner
Sealers- microns
Liners- <0.5mm
Bases- >0.5mm
Appropriate use of sealers, liners, and bases under amalgam and composite
In an indirect pulp capping procedure, all
carious, demineralized dentin is removed
in the periphery of the preparation (DEJ),
but a small amount of demineralized
dentin is left immediately over the area
of the pulp(to within 1mm). If a pulp
exposure is suspected, a calcium
hydroxide (Dycal) lining material is placed
to cover the remaining demineralized
dentin.
A sealing liner (RMGI) and/or a sealing
restoration is then placed to seal out
bacteria and their by-products.
If no exposure is suspected, omit the
CaOH.
For a direct pulp capping procedure, a
calcium hydroxide lining material is
placed on the exposed pulpal tissue
and a small amount of surrounding
dentin. A sealing liner and/or a
sealing restoration is then placed to
seal out bacteria and their byproducts.
This procedure is not indicated for
carious exposures.
Clinical Scenarios
Excavation of existing occlusal amalgams reveals dentin that is
discolored and hard.
What would your next step be if you were restoring with
amalgam?
Composite?
Excavation of existing occlusal amalgams reveals dentin that is
discolored and hard. No more excavation needed
What would your next step be if you were restoring with
amalgam? Gluma, then amalgam
Composite? Etch, prime, bond, then incremental fill
This patient presents complaining of
cold sensitivity and biting stress
sensitivity on the right side of her
mouth.
Clinical exam reveals a broken
amalgam restoration on # 31.
Pulp testing is normal.
What would you do next?
This patient presents complaining of cold
sensitivity and biting stress sensitivity on
the right side of her mouth.
Clinical exam reveals a broken amalgam
restoration on # 31, leaking margins#30.
Pulp testing is normal for both.
What would you do next?
Excavate until all of the leathery dentin
has been removed, especially from around
the DEJ.
Assess proximity to the pulp. Fill #30.
Place RMGI, and amalgam or composite
or a temporary restoration#31.
Inform the patient of the need for more
definitive treatment on #31.
This patient presents with
continual pain of three days
duration in his upper right jaw.
Clinical visual exam reveals little,
however radiographic exam
reveals a large mesial lesion on
#3.
The patient states that he “just
wants the tooth removed”.
Pulp testing is positive for
irreversible pulpitis.
If you were to excavate you
might find “D”.
This MOD preparation appears to expose
slowly progressing caries evidenced by
the darkly stained but hard dentin.
What chief concern or clinical findings
would have likely preceded this
excavation?
Excessive abrasion has resulted
in the exposure of the pulp of
#6, deep lesion #7.
The patient presents with
symptoms consistent with
irreversible pulpitis.
Your clinical pulp testing results
in a diagnosis of irreversible
pulpitis #6, reversible pulpitis
#7.
What would your treatment
plan include?
Your patient had a periodic oral evaluation at her last appointment with you.
She has been treatment planned for an OL restoration on #18, and is ready for that
procedure today.
Judging from the radiograph you are prepared for a deep excavation and have CaOH, RMGI
and amalgam ready.
What’s wrong with this picture?
Carious tooth
asymptomatic
(no indication of pulpal pathology)
extraction
CaOH direct pulp cap
GI or RMGI,
Fill & observe?????
symptomatic
endodontics
Short duration
For amal.: RMGI if deep.
Gluma if shallow.
For comp.: etch, prime, bond,
RMGI if deep
N.V. Pulp testing
endodontics
CaOH pulp cap,
Temporary fill for 3 mo.
V. Pulp testing
Excavate and fill
Long duration
spontaneous
Excavate & N.V. Pulp testing
pulpotomy or ectomy
CaOH pulp cap,
RMGI, permanent fill
Do not crown
extraction
By C. Rodriguez D.M.D.
In the end there is rest…