Transcript 5 Treatment of caries kinds, choice of method depending on a

Treatment of caries: kinds, choice
of method depending on a clinical
form. Remineralizing therapy.
Stages of surgical treatment.
Features of treatment of deep
caries. General and local
treatment of plural caries.
Medicinal facilities and physical
methods in complex therapy of
dental caries.
Therapeutic dentistry department
Lecturer: Yavors’ka-Skrabut I.M.
RATIONALE
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Incipient enamel caries is caused by
specific microorganisms

Streptoccus mutans plus sucrose
reduces the pH in the plaque to a
critical level of 5.0-5.5, which can
overcome the buffering capacity of
saliva and result in demineralization of
enamel
RATIONALE

Incipient enamel caries is caused by
specific microorganisms

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High bacterial counts are the result of
the patient’s diet, and be reduced by
altering the diet.
A high Strep. mutans count generally
indicates large and/or frequent
ingestion of sucrose.
RATIONALE

Incipient enamel caries is caused by
specific microorganisms

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A high lactobacillus count generally
indicates a high proportion of
carbohydrates in the patient’s diet.
A normal saliva flow rate (1-2 ml/minute)
and buffering capacity (5-7pH)
discourages demineralization and
encourages remineralization; a low flow
rate (0.7 ml/minute or less) and buffering
capacity (<4pH) will encourage
demineralization and caries activity
RATIONALE
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A diet diary can indicate dietary
intake, and dietary counseling may
result in an altered diet that will
decrease caries activity.
Lactobacillus counts are significantly
higher in patients with open caries
lesions; restoration of these lesions
will produce a dramatic drop in the
count.
RATIONALE
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Caries begins as a subsurface lesion
which can be remineralized as long as
the surface remains intact.
Supersaturated salivary calcium and
phosphates in the presence of fluoride
can slowly remineralize demineralized
enamel.
Remineralized enamel is more
resistant to subsequent
demineralization than original intact
enamel
RATIONALE
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The effect of oral hygiene/plaque
control on caries activity is
controversial. Oral hygiene is much
less important than diet, but
complete plaque removal daily will
reduce caries on exposed tooth
surface
RATIONALE

Various anti-microbial mouthwashes will
reduce certain cariogenic microorganisms,
but may also interfere with the normal oral
flora and allow overgrowth of undesirable
organisms. For example, Chlorohexadine
Gluconate mouthwashes may reduce Strep.
Mutans counts, but will not reach organisms
in deep lesions. Deep lesions should
therefore be eliminated with caries control
restorations before instituting anti-microbial
therapy.
RATIONALE
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Fluoride applied in various ways
(systemic, clinical and home)
decreases cariogenic organisms and
promotes remineralization.
RATIONALE
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Vigorous treatment to a testable
endpoint (the 4 lab tests of saliva at
recall) is preferable to vague,
ineffective treatment ad infinitum.
Patient are very discouraged when
they follow the dentist’s advice and
caries activity still continues.
RATIONALE

Not all patients require the same
treatment – some will be overtreated and some under-treated
unless proper diagnosis and
treatment is done. It is important to
determine which patients have the
signs, symptoms and history that
are indications of high caries
activity and need to be placed on a
Caries Risk Management Program.
Treatment planning for restorative dentistry
(high caries risk )
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The restorative treatment must be
coordinated with all the means
utilized in the Caries Risk Management
Program (diet, oral hygiene, fluoride,
antimicrobials, saliva stimulation,
etc.)
Treatment planning for restorative dentistry
( high caries risk )
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Early elimination of all dentinal
caries is very important in
eliminating the source of Strep.
Mutans. Caries control restorations
may be necessary to accomplish
this quickly.
Treatment planning for restorative dentistry
( high caries risk )
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Types of lesions and choice of
treatment:
Routine use should be made of
fluoride application to cavity
preparations and fluoride-releasing
liners, bases and restorative
materials.
Types of lesions and choice of treatment
( high caries risk )
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Smooth surface incipient caries;
Sticky pits and fissures
Sticky pits and fissures with
incipient caries
Small and moderate lesions
Deep lesions
Root caries
Types of lesions and choice of treatment
( high caries risk )
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Smooth surface incipient caries:
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Reminerlize with clinical topical fluoride
applications and home application of
fluoride by various means ; toothpaste,
rinses, brush-on gels, custom trayapplied gels, ect.
Sticky pits and fissures:
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Pit and fissure sealants
Types of lesions and choice of treatment
( high caries risk )

Sticky pits and fissures with
incipient caries
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Preventive resin/sealants (Remove
caries, place composite in the cavity
and cover all with sealant)
Definitive amalgam restorations
Small and moderate lesions
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Definitive amalgam, composite or glass
ionomer restorations
Types of lesions and choice of treatment
( high caries risk )
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Deep lesion:
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Caries control restorations with ZnOeugenol, glass ionomer or amalgam,
and the definitive resotrations after
caries activity has decreased
Root caries:
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Fluoride applications
Glass ionomer restoration
Treatment planning for restorative dentistry
( high caries risk )
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Routine use should be made of
fluoride application to cavity
preparations and fluoride releasing
liners, bases and restorative
materials
The indication for placing of patients
on a Caries Risk Management
Program
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A previous history of caries,
demonstrated by numerous
restoration, especially with
recurrent caries.
Numerous large carious lesion,
especially those with depth greater
than width.
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Unpigmented demineralized areas
on smooth surfaces, often on the
lingual third. Lesions on the lingual
surfaces indicate an even higher
risk.
Recent incidence of new lesions on
recall examinations.
Patients requiring extensive
reconstructive procedure
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Patients (especially the elderly) with
root caries.
Patients that report a history of a
physical condition, medical
treatment (especially radiation
therapy), medication and dietary
changes that would influence saliva
or oral flora
History of continued high quantity
intake of carbonated beverages
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Patients with active caries-lesions
that are unpigmented, of a soft
consistency, moist, sensitive to
Sweets, cold or excarvation, and
with depth greater than width.
DX
ACTIVE
INACTIVE
COLOR
LIGHT
DARK
CONSISTENCY MUSHY
FIRM
MOISTURE
WET
DRY
SYMPTOM
SENSITIVE
NONE
SHAPE
DEPTH>WIDTH
WIDTH>DEPTH
Caries control restoration
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The goal is elimination of the source
of cariogenic organisms by removal
of caries from all deep lesions and
placement of temporary
restorations early in the treatment.
This is very important in effecting
reversal of the active caries process.
Caries Control Restoration
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Cavity preparation is done quickly
without definitive cavity preparation.
Undermined enamel be left to aid in
retention of these treatment
restorations, especially if
restoratives are used that bond to
tooth structure.
Caries Control Restoration
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Pulpal response to the restorative
treatment can be observed and
endodontic treatment instituted if
necessary before planning definitive
restoration.
Caries Control Restoration
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The restoration protects the pulp
against further insult and promotes
healing of the lesion by
remineralization of affected dentin
and stimulation of reparative dentin.
Caries Control Restoration
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Patient comfort and mastication are
quickly improved by decreasing
sensitivity from open cavities, food
impaction, ect. Occlusal and
proximal stability is maintained.
Caries Control Restoration
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Restorative materials used for caries
control restoration.
 CaOH is bacteriocidal and stimulates
reparative dentin
 Reinforced Zinc Oxide-eugenol is
obtundant, reducing pain and
sensitivity; it is bacteriocidal to
organisms deep in the cavity, and it
seals margins well for several months,
preventing ingress of nutrients to the
organisms. Strength is fair.
Caries Control Restoration
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Restorative materials used for caries control
restoration.
 Glass ionomer-bonds to tooth structure for
improved retention, it release fluoride which
reduces organisms and promotes
remineralization, has good marginal seal,
fair strength, and is esthetically pleasing.
 Amalgam has excellent strength, maintains
occlusal and proximal relationships, fair
marginal seal, best for long term temporary
Caries Control Restoration
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Similar restorations can be used to
quickly restore deep lesions for
emergency patients when time is limited.
Caries control restorations should be left
in place until caries activity tests indicate
a significant decrease in caries activity.
Definitive restorations can then be placed
with a promise of much greater longevity.
Caries Control Restoration
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Indirect pulp capping is often done
in conjunction with caries control
restorations.
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Pulp must show radiographic and
clinical signs and symptoms of vitality.
All caries is removed at the periphery,
establishing a sound DEJ.
Caries Control Restoration
Caries Control Restoration
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Indirect pulp capping is often done in
conjunction with caries control restorations.
 All infected dentin is excavated with
large round burs and excavators, being
careful not to expose the pulp. Basic
fuchsin effectively identifies infected
dentin.
 A small amount of firm caries (affected
dentin) is left over sites of potential
exposure.
Caries Control Restoration

Indirect pulp capping is often done
in conjunction with caries control
restorations.
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Calcium hydroxide liner is placed in the
deepest areas. The high pH of the
CaOH will neutralize acid, kill bacteria
and stimulate formation of restorative
dentin.
The resin-forced ZOE, glass ionomer or
amalgam restoration is placed
Caries Control Restoration

Indirect pulp capping is often done
in conjunction with caries control
restorations.

After 6-8 weeks the entire restoration
is removed, any remaining caries is
removed and a definitive restoration is
planned.
Pit & Fissure Sealing
Techniques
Glass ionomer sealants
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Chemical bond to enamel.
Fluoride release.
New GIC material- Fuji 7 high fluoride release (6 x
more) than other restorative GICs.
has good flow properties and flow well into
pits/fissures.
moisture tolerant.
has a strong fused layer which is acid resistant &
continues to offer protection to occlusal surface
even when it appears “visually” lost due to wear.
Restorative GICs tend not to be suited as
fissure sealants as are thicker and do not
flow well into narrow/deep pits & fissures
Glass ionomer sealants
Partially erupted teeth, Seal or wait until
fully erupted?
For composite resin:
If seal whilst partially erupted:

Risk of sealant failure
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Risk of caries development
For Glass Ionomer Fissure sealant:
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can be placed in situations where tooth can be
partially erupted because of its ability to be
placed in conditions where moisture control can
not be optimally maintained.
Diagnosis of pit/fissure caries
Diagnosis of pit/fissure caries - can be
very difficult!
3 Possibilities:
1. No caries
2.
3.
Definite caries
Questionable caries
Is there caries or is this only
stain?
Management of Questionable pit/fissure
early caries
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Monitor tooth surface over period of time
in conjunction with other caries preventive
measures.
Mechanically open up fissures with a
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bur/air abrasion and check if carious
(invasive?)
Fissure seal with fissure sealant.
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Moisture control
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Rubber dam
 single or multiple isolation
Relative isolation with cotton roll
Fissure exploration
Bur tip should be as fine as possible.
L 10
L 20
Fissure exploration
Place bur in central fossa of occlusal fissure.
Upright bur so that it is in the long axis of the
tooth; however, bur can be leant towards the
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‘direction of travel’ movement, away from the tip.
Depth is determined by:
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depth of staining present
what is required to alter the
anatomy of the fissure so that
the sealant can flow to its full
depth (approx 0.5mm).
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Avoid cuspal inclines.
Note that the depth may therefore vary.
Demonstrates initial investigation to distal
part of occlusal fissure system
Initial investigation into complete fissure
system
Completed fissure investigation
1. Wash
(5 seconds)
2. Dry with mild air
(10 seconds)
Completed fissure investigation (cont.)
Visually check the prepared fissure system:
•
Any staining?
•
Is it clean?
(Note that the depth may vary.)
Fissure sealant materials

Select appropriate material to complete the
fissure sealant.
You can use:
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resin system
•
Glass Ionomer Cement (G.I.C) system,
•
Resin Modified Glass Ionomer Cement (RMGIC)
Application of etchant
Apply etchant to fissure system for 15 seconds.
Wash thoroughly for minimum 20 seconds to
remove etchant.
Dry thoroughly.
Note that natural tooth should have a
frosty appearance.
Applying sealant
Step 1
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Spread sealant evenly.
One can use applicator or micro-brush,
or sealant can be applied directly to
surface.
Avoid porosity (bubbles).
(DO NOT blow air to spread the sealant.)
Applying sealant
Step 2

Note that the occlusal fissure system is
completely covered with resin material but
does not extend up to the cusps.
Light cure resin material for 20
seconds.
Checking the sealant

Using explorer:
 ensure material is completely cured
 check margins
 ensure material is bonded to enamel.
Composite resin finishing point
Treatment of dental caries by:
AMALGAM.
Properties, indications, inserting,
carving, polishing.
AMALGAM
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Amalgam is the most widly used
permanent filling in dentistry. It is
prepared by mixing the alloy with
mercury.
The reaction between mercury and alloy
is termed an amalgamation reaction.
It results in the formation of a hard
restorative material of silvery – grey
appearance
Amalgam Use and Benefits
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Dental amalgam, in widespread use for over 150
years, is one of the oldest materials used in oral
health care.
Its use extends beyond that of most drugs, and
is predated in dentistry only by the use of gold.
Dental amalgam is the end result of mixing
approximately equal parts of elemental liquid
mercury (43 to 54%) and an alloy powder (57
to 46%)
composed of silver, tin, copper, and sometimes
smaller amounts of zinc, palladium, or indium.
Amalgam
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MERCURY (Hg) – is a liquid at room
temperature and it is able to form a workable
mass when mixed with the alloy.
The reaction between mercury and alloy is termed
an amalgamation reaction.
Dental amalgam has been used for many years
with a large measure of success.
It is the most widely used of all available filling
materials.
Composition
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The composition of the alloy powder particles
varies from one product to another.
Composition of CONVENTIONAL AMALGAM
ALLOY:
Metal:
Weight:
Silver (Ag) .......................... 65% min.
Tin (Sn)
..............................29% max.
Copper (Cu) ..............................6% max.
Zinc (Zn)
...............................2% max.
Mercury (Hg) ............................ 3% max.
Composition
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1. Silver - Increases strength, expansion
and reactivity. Decreases creep.
Corrosion products are AgCl and AgS.
2. Tin - Increases reactivity and
corrosion. Decreases strength and
hardness. Corrosion products are SnO,
SnCl, and SnS.
3. Copper - Increases strength,
expansion and hardness. Decreases
creep. Corrosion products are CuO and
CuS.
Composition
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4. Zinc - Increases plasticity, strength
and the Hg:alloy ratio. Decreases creep.
Causes secondary expansion. Corrosion
products are ZnCl and ZnO.
5. Mercury - Wets the alloy particles.
Decreases strength if in excess amounts.
Implicated in toxic and allergic reactions.
Effects on properties of an amalgam restoration
imparted by ingredients.
PROPERTY
INGREDIENT
Silver
Strength
Increases
Durability
Increases
Tin
Hardness
Copper
Increases
Expansion
Increases
Decreases
Increases
Flow
Decreases
Increases
Decreases
Color
Imparts
Increases
Decreases
Setting time
Workability
Cleanliness
Zinc
Decreases
Increases
Increases
Increases
Amalgam
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The role of zinc (Zn) :
is as a SCAVENGER during the production of the
alloy. The alloy is formed by melting all the
constituent metals together.
There are tendency for oxidation to occur.
OXIDATION of tin (Sn), copper (Cu) or silver
would seriously affect the properties of the alloy
and amalgam.
Zinc reacts rapidly and preferentially with the
available oxygen, forming a slag of zinc oxide
(ZnO) which is easily removed.
Many alloys contain no zinc. They are described
as ZINC- FREE ALLOYS.
Amalgam: properties
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1.
2.
3.
4.
5.
6.
DIMENSIONAL CHANGES
STRENGTH
PLASTIC DEFORMATION (CREEP)
CORROSION
THERMAL PROPERTIES
BIOLOGICAL PROPERTIES
1. DIMENSIONAL CHANGES
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A large contraction would result in a marginal
gap down which fluids could penetrate.
A large expansion would result in the protrusion
of the filling from the cavity.
Zinc reacts readily with water producing
hydrogen:
Zn + H2O –––––––––––– ZnO + H2
The liberation of hydrogen (H2) causes
a considerable expansion.
2. STRENGTH
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The strength of dental amalgam is developed
slowly. It may take up to 24 hours to reach
a reasonably high value and continues to increase
slightly for some time after that.
15 – 20 minutes after placing the filling , the AM
is relatively weak. It is necessary, to instruct
patients not to apply undue stress to their freshly
placed AM fillings.
There is good correlation between strength and
mercury content.
Optimum properties are produced for amalgams
containing 44-48% mercury.
3. PLASTIC DEFORMATION (CREEP)
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Amalgam undergoes a certain amount of plastic
deformation or creep when subjected to dynamic
intra-oral stresses.
The gamma 2 phase of AM is responsible for the
relatively high values of creep.
The copper- enriched amalgams, which contain
little or no gamma 2 in the set material, have
significantly lower creep values
Gamma 2 phase is responsible for high
creep.
4. CORROSION
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Corrosion is a matter which may significantly affect the structure
and machanical properties. The heterogeneous, multiphase
structure of AM makes it prone to corrosion.
The gamma 2 phase of a conventional AM is the most
electrochemically reactive and readily forms the anode in an
electrolytic cell.
The rate of corrosion is accelerated if the AM filling contacts
a gold restoration.
Smooth surfaces are less prone to concentration cell corrosion.
5. THERMAL PROPERTIES
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AM has a relatively high value of thermal
diffusivity
Dentine is replaced by a good thermal conductor.
The coefficient of thermal expansion value
for AM is about three times greater than that
for dentine.
This results in considerably more expansion and
contraction in the restoration than in the
surrounding tooth when a patient takes hot or
cold food or drink.
Thermal expansion may cause microleakage
around the fillings since is no adhesion between
AM and tooth substance.
Microleakage plays an important part in initiating
such lessions.
6. BIOLOGICAL PROPERTIES
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Certain mercury compounds are known to
have a harmfull effect on the central nervous
system.
Some studies have shown a higher concentration
of mercury in the blood and urine of patients with
AM fillings than those without.
Another potential problem concerns allergic
reactions, usually manifested as a contact
dermatitis.
Mercury or freshly mixed AM should never be
touched by hand.
Mercury is readily absorbed by the skin.
Usage and preparation of amalgam
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The dental specialist has the direct
responsibility for the correct
preparation and use of amalgam.
Incorrect use may produce a faulty
restoration that can cause or contribute to
the loss of a tooth.
Therefore, the dental specialist must use
extreme care in preparing a good mix
of amalgam that will provide the best
qualities obtainable from the alloy.
MANIPULATIVE VARIABLES
The manipulating of AM involves the
following sequence of events:
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1. Proportioning and dispensing
2. Trituration
3 Condensation
4.Carving
5. Polishing
1. PROPORTIONING AND DISPENSING
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Alloy/mercury ratios vary between
5:8 and 10:8.
Those mixes containing greater
quantities of mercury are „wetter“ and
are generally used with hand mixing.
Those mixes containing smaller
quantities of mercury are „drier“ and are
generally used with mechanical mixing.
Spherical particle alloys,for example , require less
mercury to produce a workable mix.
1. PROPORTIONING AND DISPENSING
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For optimum properties, the final
set amalgam should contain less
than 50% mercury.
The optimal final mercury content
ranges from an average of 45% for
lathe-cut materials to an average of
40% for spherical materials.
2. TRITURATION
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The mixing or trituration of AM may be
carried out by hand or in an
electrically powdered machine
which vibrates a capsule containing the
mercury and alloy.
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Trituration by hand is not extensively
practised in developed countries
nowadays. Mechanical mixing is far more
widely used - amalgamator.
Trituration times 5 - 20 seconds are
normal.
2. TRITURATION
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The advantages of mechanical trituration
are as follows:
1. A uniform and reproducible mix is produced.
2. A shorter trituration time can be used.
3. A greater alloy/mercury ratio can be used.
Amalgamator
3. CONDENSATION
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Material is condensed into the prepared cavity
using a flat-ended, steel hand instrument called
an amalgam condenser.
The technique chosen for condensation must
ensure the following.
1. Adequate adaptation of the material to all parts
of the cavity base and walls.
2. Good bonding between the incremental layers
of amalgam
3. Optimal mechanical properties in the set
amalgam by minimizing porosity and achieving
a final mercury content of 44-48%.
3. CONDENSATION
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There should be a minimal time delay
between trituration and condensation.
If condensation is commended too
late, the amalgam will have achieved
a certain degree of set and adaptation,
and final mechanical properties are all
affected.
There is a good correlation between
the quality of an AM restoration and
the energy expended by the operator
who condenses it.
It needs to use a high condensating
force.
Lower forces are required to condense
spherical particle amalgams than
lathe-cut materials.
Condensing instruments

Amalgam carriers
this purpose.
and condensers are used for
4. CARVING
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Soon after condensing the AM, the surface layer ,
which is rich in mercury, is carved away with
a sharp instrument.
If carving is delayed too long the material may
become too hard to carve and there is a danger of
chipping at the margins.
4. CARVING
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Amalgam carvers
5. POLISHING
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Polishing is carried out in order to achieve
a lustrous surface having a more acceptable
appearance and better corrosion resistance.
The fillings should not be polished untill the
material has achieved a certain level of
mechanical strength, otherwisw there is a danger
of fracture , particularly at the margins.
Many products require a delay of
24 hours between placing and
polishing.
5. POLISHING
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Polishing kits
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Polishers
Black
Dark purple
Green
Amalgam indications
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In primary and permanent dentition
In stress bearing areas of the mouth
Small to moderate - sized cavities in the
posterior teeth
As a foundation to crowns
When oral hygiene is bad
When moisture control is a problem
When cost is a concern
Amalgam contraindications
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When esthetics is important
When patient has a history of allergic
reactions to the alloy
When cost is not a concern
Amalgam fillings
Amalgam fillings