Indication to the Type of Restoration

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(1)

Indication to the

Indication to the

type of restoration

type of restoration

O.R.GaneshMurthi O.R.GaneshMurthi M.Sc.D Endo M.Sc.D Endo student student

(2)
(3)

The tooth as a house

The tooth as a house

(4)

In

In

troductio

troductio

n

n

Teeth that require endodontic treatment are Teeth that require endodontic treatment are

often severely broken down and can be vulnerable often severely broken down and can be vulnerable to fracture; they often require extensive (and

to fracture; they often require extensive (and expensive) restoration following root canal expensive) restoration following root canal treatment.

treatment.

 A high fracture rate has been found in root-filled  A high fracture rate has been found in root-filled

teeth that have mesial Occlusal distal (MOD) teeth that have mesial Occlusal distal (MOD) amalgam restoration

amalgam restorations, and s, and it is it is often good practiceoften good practice to place some form of cusp coverage restoration to to place some form of cusp coverage restoration to prevent destructive flexure during mastication.

(5)

F

(6)

E

E

n

n

dodo

dodo

n

n

tically treated teeth are

tically treated teeth are

usually weak 

usually weak 

 loss of tooth structureloss of tooth structure

(7)

There is good evidence from There is good evidence from scientific studies that the

scientific studies that the quality of coronal seal

quality of coronal seal

affects the prognosis of root affects the prognosis of root canal treatment. It takes a canal treatment. It takes a relatively short time for the relatively short time for the root-filled tooth

root-filled tooth to b

to becoecome reme reinfinfectecteded if it isif it is left exposed to the

left exposed to the oral cavity.

oral cavity.

S

(8)

treatme

treatme

n

n

t pla

t pla

nn

nn

i

i

ng

ng

 EExisting endodontically treated teeth need to bexisting endodontically treated teeth need to be

assessed care-fully for the following: assessed care-fully for the following:

 Good apical sealGood apical seal

 No sensitivity to pressureNo sensitivity to pressure

 No exudateNo exudate

 No fistulaNo fistula

 No apical sensitivityNo apical sensitivity

(9)

objectives of restoratio

objectives of restoratio

n

n

e

e

n

n

dodo

dodo

n

n

tically

tically

treated tooth

treated tooth

S S

tated as µ3R¶s

tated as µ3R¶s

  ReinforcementReinforcement   ReplacementReplacement   RetentionRetention

(10)

ei

ei

n

n

forceme

forceme

n

n

t

t

ei

ei

n

n

forceme

forceme

n

n

t

t

 Reinforcement of theReinforcement of the

remaining tooth remaining tooth

structure is achieved structure is achieved with dowel and coping with dowel and coping

  DOWDOWELEL ±± ppoosstt extending extending approximately 2/3 approximately 2/3rdrd

the length of the root the length of the root canal

canal

 A

(11)

eplaceme

eplaceme

eplaceme

eplaceme

n

n

n

n

t

t

t

t

Replacement of missing Replacement of missing tooth structure is

tooth structure is

achieved with the core achieved with the core COR

COREE ±± is is ththe ce cororononalal

extension of the dowel extension of the dowel that provide optimal that provide optimal retention for final

retention for final Restoration.

Restoration.

B

(12)

ete

ete

ete

ete

n

n

n

n

tio

tio

tio

tio

n

n

n

n

Is supplied by

Is supplied by

1.

1.

Dowel for core

Dowel for core

2.

(13)

Co

Co

n

n

sideratio

sideratio

n

n

s for a

s for a

n

n

terior teeth

terior teeth

 Anterior teeth do not always need complete  Anterior teeth do not always need complete

coverage, except when plastic restorative coverage, except when plastic restorative materials woul

materials would d have limited prognosis in viewhave limited prognosis in view of the extent of coronal destruction. Many

of the extent of coronal destruction. Many function with composite resin

function with composite resin restorationrestorations.s.

when the tooth is loaded, stresses are greatest when the tooth is loaded, stresses are greatest at the facial and lingual surfaces of the root

at the facial and lingual surfaces of the root and an internal post, being only minimally and an internal post, being only minimally stressed, does not help prevent fracture stressed, does not help prevent fracture

(14)

 protectio

 protectio

n

n

of

of

a

a

n

n

terior teeth?

terior teeth?

Coronal coverage does

Coronal coverage does

not

not

significantlysignificantly improve the success of Anterior RCT

(15)

a

a

.I

.I

t

t

ac

ac

t

t

a

a

r

r

i

i

a

a

l ri

l ri

.I

.I

t

t

ac

ac

t

t

c

c

i

i

l

l

(

(

a

a

ll

ll

access

access

en

en

i

i

ng

ng

)

)

c

c

.

.

I

I

n

n

t

t

ac

ac

t i

t i

nc

nc

i

i

sa

sa

l

l

edge

edge

d

d

.

.

-

-

sma

sma

l

l

l

l

r

r

i

i

ma

ma

l

l

l

l

es

es

i

i

ns

ns

/r 

/r 

es

es

t

t

a

a

ti

ti

ns

ns

M

M

i

i

n

n

imal coro

imal coro

n

n

al dama

al dama

g

g

e

e

Wh

Wha

at i

t is

s th

the

e fi

fina

nall r 

r es

estt r 

r a

ati

ti n

n f thi

f this

s ty

ty e

e f 

case

case ?

?

R

Res

estt r 

r e

e access

access

en

eniing

ng with

with a

a compos

composit

ite

e

(16)

si

si

gn

gn

ifica

ifica

n

n

t coro

t coro

n

n

al dama

al dama

g

g

e

e

undermined marginal ridges

undermined marginal ridges

loss of incisal edge

loss of incisal edge

coronal fracture/esthetically

coronal fracture/esthetically

unacceptable

unacceptable

What is the final restoration of this type of case ? What is the final restoration of this type of case ?

Post/core Post/core

-small circular canal

-small circular canal  acceptable to use prefabacceptable to use prefab post + resin(must have at least 2mm of

post + resin(must have at least 2mm of toothtooth

structure apical to resin core); however, cast post structure apical to resin core); however, cast post and core best treatment

and core best treatment -elliptical/flare

-elliptical/flared d canalcanal  custom cast post/corecustom cast post/core

F

(17)

do all

do all

CT teeth

CT teeth

n

n

eed ³protectio

eed ³protectio

?

?

do all

do all

CT teeth

CT teeth

n

n

eed ³protectio

eed ³protectio

?

?

A

Ann

teriors

teriors

Posteriors

Posteriors

Y

YESES

!!!!!!!!!! (unless not in

!!!!!!!!!! (unless not in

occlusion)

occlusion)

No, But may need post/core to r

No, But may need post/core to r

estore

estore

tooth

(18)

Co

Co

n

n

sideratio

sideratio

n

n

s for posterior teeth

s for posterior teeth

E

Endodonticallyndodontically

treated posterior  treated posterior  teeth are subject to teeth are subject to greater loading than greater loading than anterior teeth are

anterior teeth are because of their  because of their 

position closer to the position closer to the insertion of the

insertion of the

masticatory mus-cles masticatory mus-cles..

(19)

P

P

arts of prosthodo

arts of prosthodo

n

n

tic reco

tic reco

n

n

structio

structio

n

n

P

P

arts of prosthodo

arts of prosthodo

n

n

tic reco

tic reco

n

n

structio

structio

n

n

compared with chai

compared with chai

n

n

li

li

n

n

ks

ks

compared with chai

(20)

esi

esi

n

n

restoratio

restoratio

n

n

i

i

n

n

access ope

access ope

n

n

i

i

ng

ng

Indication

Indication

Intact anterior tooth with only an access Intact anterior tooth with only an access opening or very small class III restoration opening or very small class III restoration

Contraindications

Contraindications

Numerous or large restoration in

Numerous or large restoration in toothtooth resul

resulting ting in exin extentensive desive desturctsturctionion mostmost posterior teeth

(21)

esi

esi

n

n

restoratio

restoratio

n

n

i

i

n

n

access ope

access ope

n

n

i

i

ng

ng

 Advantages

 Advantages

  1 appointment1 appointment   CostCost 

 Preserve tooth structurePreserve tooth structure

 EEstheticssthetics

Disadvantages

Disadvantages

(22)

Amal

Amal

g

g

am core fou

am core fou

n

n

datio

datio

n

n

Amal

Amal

g

g

am core fou

am core fou

n

n

datio

datio

n

n

Indication

Indication

Posterior teeth that are to receive crowns Posterior teeth that are to receive crowns

cuspal coverage can be considered for strength cuspal coverage can be considered for strength as an option to crown

as an option to crown

Contraindication

Contraindication

Teeth in which a bulk of am

Teeth in which a bulk of amalgam cannot bealgam cannot be obtained

(23)

TY

TY

PESPES

TY

TY

PES OFPES OFOF POSOF POSPOSPOS

T

T

T

T

SSSS

M

M

EE

T

TA

A

LLLL

IIC

C

N

NO

ON

N--M

M

EE

T

TA

A

LLLL

IC

IC

 SS

tai

tai

n

n

less

less

SS

teel

teel

Tita

Tita

n

n

ium

ium

Tita

Tita

n

n

ium Alloy

ium Alloy

Gold-

Gold-

PP

lated

lated

 brass

 brass

Carbon

Carbon

FF

ibre

ibre

 

Ceramic

Ceramic

 

Glass-fibre

Glass-fibre

reinforced

reinforced

 

Composite

Composite

(24)

Custom cast post a

Custom cast post a

n

n

d core

d core

Custom cast post a

Custom cast post a

n

n

d core

d core

Advantages:

Advantages:

 Preservation of maximumPreservation of maximum

tooth structure tooth structure

 Provision of anti-rotationalProvision of anti-rotational

properties properties

 Core retentionCore retention

 LLess chances of verticaless chances of vertical

fractures during preparation fractures during preparation

 High strengthHigh strength

Di

Di

sadvantages:

sadvantages:

 LLess stiff thaness stiff than

wrought wrought

 Time consuming,Time consuming,

complex procedure complex procedure

Recommended Use: Recommended Use:

E

Elliptical calliptical cannalsals F

(25)

P

P

refab

refab

ricat

ricat

ed T

ed T

apered

apered

P

P

ost

ost

P

P

refab

refab

ricat

ricat

ed T

ed T

apered

apered

P

P

ost

ost

Advantages:

Advantages:

 Conserves toothConserves tooth

structure structure

 High strength andHigh strength and

stiffness stiffness

Di

Di

sadvantages:

sadvantages:

  LLow retentionow retention 

 LLongitudinal splittingongitudinal splitting

of remaining root of remaining root

Recommended Use: Recommended Use:

S

S

mall circular ca

mall circular ca

n

n

als or 

als or 

Very tapered ca

(26)

P

P

refabricated

refabricated

P

P

arallel

arallel

P

P

refabricated

refabricated

P

P

arallel -

arallel -

-

-

S

S

S

S

ided

ided

ided

ided

S

S

mooth

mooth

P

P

ost

ost

S

S

mooth

mooth

P

P

ost

ost

Advantages:

Advantages:

 EExcellent clinicalxcellent clinical

retention retention

 Minimal stressMinimal stress

production within root production within root

 EEase of placementase of placement

 SSuperior ratinguperior rating

Di

Di

sadvantages:

sadvantages:

 Precious materialPrecious material

post expensive post expensive

 Corrosion of Corrosion of 

stainless-steel stainless-steel

 LLess conservative of ess conservative of 

tooth structure tooth structure

(27)

P

P

refabricated Threaded

refabricated Threaded

P

P

osts

osts

P

P

refabricated Threaded

refabricated Threaded

P

P

osts

osts

Advantages:

Advantages:

 High retentionHigh retention

Di

Di

sadvantages:

sadvantages:

 SStresses generated intresses generated in

canal may lead to canal may lead to fracture

fracture

 Does not conserveDoes not conserve

coronal and radicular  coronal and radicular  tooth structure

tooth structure

Recommended Use: Recommended Use:

O

Onnllyy wwhheenn maximummaximum rete

(28)

F

F

iber 

iber 

ei

ei

n

n

forced

forced

P

P

ost

ost

F

F

iber 

iber 

ei

ei

n

n

forced

forced

P

P

ost

ost

Advantages:

Advantages:

  EEstheticsthetic

Di

Di

sadvantages:

sadvantages:

  LLow strengthow strength 

 High failure rateHigh failure rate

Recommended Use: Recommended Use:

S

S

hould

hould

n

n

ot be used where r

ot be used where remai

emai

n

n

ii

ng

ng

tooth structure is less tha

tooth structure is less tha

n

n

ideal or where

ideal or where

hi

(29)

Z

Z

irco

irco

n

n

ia Ceramic

ia Ceramic

P

P

ost

ost

Z

Z

irco

irco

n

n

ia Ceramic

ia Ceramic

P

P

ost

ost

Advantages:

Advantages:

 EEstheticssthetics

 High stiffnessHigh stiffness

 High modulus of High modulus of 

elasticity elasticity

Di

Di

sadvantages:

sadvantages:

  EExpensivexpensive 

 Uncertain clinicalUncertain clinical

performances performances

Recommended Use: Recommended Use:

H

(30)

Cast metal post a

Cast metal post a

n

n

d core

d core

Cast metal post a

Cast metal post a

n

n

d core

d core

Indication

Indication

Teeth in which minimal tooth structure remains Teeth in which minimal tooth structure remains a tooth that is to be used as an abutment for  a tooth that is to be used as an abutment for  fixed partial denture.

fixed partial denture.

Contraindications

Contraindications

Teeth requiring some types of very translucent Teeth requiring some types of very translucent all ceramic crowns

(31)

Cast metal post a

Cast metal post a

n

n

d core

d core

Cast metal post a

Cast metal post a

n

n

d core

d core

 Advantages

 Advantages

S

Strength post and core one unittrength post and core one unit

Relative easy to incorporate anti rotation feature Relative easy to incorporate anti rotation feature

Disadvantages

Disadvantages

Numerous

Numerous appointappointmentsments Cost

Cost

More tooth removal More tooth removal

(32)

Ceramic post a

Ceramic post a

n

n

d core

d core

Ceramic post a

Ceramic post a

n

n

d core

d core

Indication

Indication

Teeth requiring some type of very translucent Teeth requiring some type of very translucent all ceramic crowns

all ceramic crowns

Contraindication

Contraindication

Teeth for which a metal ceramic crown is Teeth for which a metal ceramic crown is planned

(33)

Ceramic post a

Ceramic post a

n

n

d core

d core

Ceramic post a

Ceramic post a

n

n

d core

d core

 Advantages

 Advantages

E Estheticssthetics

Disadvantages

Disadvantages

Numerous

Numerous appointappointmentment Cost

Cost

L

Long term data are limitedong term data are limited

Ceramic materials may have a tendency to Ceramic materials may have a tendency to fracture

(34)

Crow

Crow

n

n

placeme

placeme

n

n

t

t

Crow

Crow

n

n

placeme

placeme

n

n

t

t

Indication

Indication

E

Enhancement nhancement of of esthetic esthetic outcome outcome situation situation inin

which existing restoration combined with the which existing restoration combined with the endodo

endodontic access under ntic access under mine the structure if mine the structure if  crown

crown

Contraindication

Contraindication

 Anterior teeth that have only a conservative  Anterior teeth that have only a conservative

endodontic access opening endodontic access opening

(35)

Crow

Crow

n

n

placeme

placeme

n

n

t

t

Crow

Crow

n

n

placeme

placeme

n

n

t

t

 Advantages

 Advantages

Protection of reaming tooth structure by Protection of reaming tooth structure by encirclement

encirclement

Disadvantages

Disadvantages

Removal of more tooth structure Removal of more tooth structure cost

(36)

Crow

Crow

n

n

placeme

placeme

n

n

t

t

Crow

Crow

n

n

placeme

placeme

n

n

t

t

Indication

Indication

E

Enhancement onhancement of esthetics out cf esthetics out come situation inome situation in

which existing restorations combined with the which existing restorations combined with the endod

endodontic access ontic access undermine the structureundermine the structure integrity of the natural crown

integrity of the natural crown

Contraindications

Contraindications

 Anterior teeth that have only a conservative  Anterior teeth that have only a conservative

endodontic access opening endodontic access opening

(37)

metal

metal

metal-metal-

-ceramic crow

-ceramic crow

ceramic crow

ceramic crow

n

n

n

n

s

s

s

s

Metal-ceramic crowns are very strong and Metal-ceramic crowns are very strong and resist occlusal loads well. Minimal

resist occlusal loads well. Minimal preparat

preparation (0.5 mmion (0.5 mm) is required on the) is required on the pala

palatal antal and appd approxroximalimal surfasurfaces. ces. This maThis mayy be beneficial in a root-filled tooth with little be beneficial in a root-filled tooth with little remaining coronal tooth substance

(38)

metal

metal

metal-metal-

-composite crow

-composite crow

composite crow

composite crow

n

n

n

n

s

s

s

s

Metal-composite crowns are often used as Metal-composite crowns are often used as long-term provisional restorations. The

long-term provisional restorations. The comp

(39)

metal

metal

metal-metal-

-free crow

-free crow

free crow

free crow

n

n

n

n

s -

s -

s

s

-porcelai

-porcelai

 porcelai

 porcelai

n

n

n

n

jacket

jacket

jacket

jacket

crow

crow

n

n

crow

crow

n

n

Porcelain jacket crowns require a buccal tooth Porcelain jacket crowns require a buccal tooth reduction of between 0.8 and 1.3 mm, and can reduction of between 0.8 and 1.3 mm, and can therefore be more conservative on tooth

therefore be more conservative on tooth substance than a m

substance than a metal-ceramic crown.etal-ceramic crown. SStainedtained

dentine and metal posts affect the aesthetic dentine and metal posts affect the aesthetic appearance of a porcelain jacket crown.

appearance of a porcelain jacket crown.

E

Excessive occlusal loading may be a problemxcessive occlusal loading may be a problem

and can result in unpredictable fracture. and can result in unpredictable fracture.

(40)

M

M

M

M

esio

esio

esio-

esio-

-occlusal cavities

-occlusal cavities

occlusal cavities

occlusal cavities

Plastic Restorative Tech

Plastic Restorative Tech

nn

iques

iques

The best method of restoring a root-treated The best method of restoring a root-treated tooth with an existing proximal box depends tooth with an existing proximal box depends on the size and depth of the box and on the on the size and depth of the box and on the occlusal stresses that are applied during

occlusal stresses that are applied during

mastication. In a case with a shallow box and mastication. In a case with a shallow box and no evidence of occlusal loading, an amalgam no evidence of occlusal loading, an amalgam restoration could be used

(41)

co

co

n

n

servative cuspal covera

servative cuspal covera

g

g

e

e

co

co

n

n

servative cuspal covera

servative cuspal covera

g

g

e

e

restoratio

restoratio

n

n

s

s

restoratio

restoratio

n

n

s

s

 A bevelled margin of I m

 A bevelled margin of I mm depth is preparedm depth is prepared around the circumference of the tooth.

around the circumference of the tooth.

Base metal alloys can be bonded to the etched Base metal alloys can be bonded to the etched occlusal surface of the tooth using a silane

occlusal surface of the tooth using a silane bonding system.

bonding system. EExtra retention will be providedxtra retention will be provided

by the internal contours of the access by the internal contours of the access

cavity, the majority of which is packed with cavity, the majority of which is packed with IRM.

(42)

P

P

P

P

lastic restoratio

lastic restoratio

lastic restoratio

lastic restoratio

n

n

n

n

The cusps are reduced in height and the entire The cusps are reduced in height and the entire occlusal surface is rebuilt in am

occlusal surface is rebuilt in amalgam. Thealgam. The technique is technically demanding since the technique is technically demanding since the

correct occlusal contacts are difficult to achieve, correct occlusal contacts are difficult to achieve, and the material must be thick enough to

and the material must be thick enough to withstan

withstand occlusal d occlusal forces (2-3 mmforces (2-3 mm). Direct light). Direct light cured composite materials are not really

cured composite materials are not really suitablesuitable for use in this situation, and indirect composite for use in this situation, and indirect composite or porcelain restorations

(43)

C

C

Cast restoratio

Cast restoratio

ast restoratio

ast restoratio

n

n

n

n

s

s

s

s

If a metal-ceramic crown is

If a metal-ceramic crown is requiredrequired,,

significantly more tooth substance will need to significantly more tooth substance will need to be removed (at least 1-1.5 mm)

be removed (at least 1-1.5 mm). The clinician. The clinician needs to be sure that sufficient tooth substance needs to be sure that sufficient tooth substance will remain after preparation for retention of the will remain after preparation for retention of the restoration to avoid an unnecessarily weakened restoration to avoid an unnecessarily weakened tooth.

(44)

Core

Core

Core

Core

M

M

M

M

aterials

aterials

aterials -

aterials -

-

-

Amal

A

A

Amal

m

m

a

a

l

l

g

g

g

g

am

am

am

am

It is strong and easy to use. Added retention It is strong and easy to use. Added retention can be gained by packing the amalgam into can be gained by packing the amalgam into irregularities and undercuts in the pulp

irregularities and undercuts in the pulp

chamber and by using grooves, slots and pits chamber and by using grooves, slots and pits in the cavity walls.

in the cavity walls. SSelf-tapping dentine pinself-tapping dentine pins

are rarely needed, and they may impart are rarely needed, and they may impart unwanted stresses within the dentine. unwanted stresses within the dentine.

(45)

The

The

The Nayyar 

The Nayyar 

N

N

ay

ay

y

y

ar

ar

c

c

core

core

or

or

e

e

The Na

The Nayyyyarar core is a ucore is a usefuseful means ol means of restof restoringring a molar tooth after root treatment when there is a molar tooth after root treatment when there is sufficient remaining tooth substance to support sufficient remaining tooth substance to support the core. Amalgam is packed into the root

the core. Amalgam is packed into the root

canals to a depth of approximately 3 mm and canals to a depth of approximately 3 mm and into the pulp chamber to give mechanical

into the pulp chamber to give mechanical retention. An adhesive can be used to give retention. An adhesive can be used to give extra retention

(46)

Composite

Composite

Composite

Composite

Composite cores have the advantage that Composite cores have the advantage that they can be built up and prepared at the they can be built up and prepared at the same visit. Chemically activated m

same visit. Chemically activated materialsaterials such as Ti Core, have been shown to

such as Ti Core, have been shown to perform well.

perform well.

There is some concern in the literature There is some concern in the literature that there may be risk of m

that there may be risk of microleakageicroleakage between the composite core and dentine between the composite core and dentine

(47)

Cermets

Cermets

Cermets

Cermets

 Alth

 Althougough h cermetcermetss have have beebeenn recommen

recommendedded as core as core materimaterials tals they ahey arere not as durable as amalgam or composite. not as durable as amalgam or composite. Cermet

Cermetss are are easy easy to use to use and band bond tond too tooth substance. They should not be tooth substance. They should not be

used when strength is required, but they used when strength is required, but they could be used as a space filler

could be used as a space filler to reduceto reduce the amount of alloy required in a cast

the amount of alloy required in a cast restoration

(48)

Crow

Crow

n

n

s for 

s for 

P

P

osterior Teeth

osterior Teeth

Crow

Crow

n

n

s for 

s for 

P

P

osterior Teeth

osterior Teeth

C

C

ast Metal

ast Metal

CC

row

row

nn

s

s

High noble metal alloys are considered to be High noble metal alloys are considered to be best since they have the greatest resistance to best since they have the greatest resistance to corrosion and tarnishing and are easy to work corrosion and tarnishing and are easy to work with. Metal crowns are excellent in situations with. Metal crowns are excellent in situations where the patient is not concerned with

where the patient is not concerned with the appearance of metal.

the appearance of metal. SSignificantly lessignificantly less

reduction in the tooth is required reduction in the tooth is required

(49)

P

P

artial Cast

artial Cast

M

M

etal Crow

etal Crow

n

n

s

s

P

P

artial Cast

artial Cast

M

M

etal Crow

etal Crow

n

n

s

s

Partial cast metal crowns may be used when Partial cast metal crowns may be used when the buccal surface of the tooth is intact. They the buccal surface of the tooth is intact. They are more conservative of tooth tissue than are more conservative of tooth tissue than

complete crowns, but they are more demanding complete crowns, but they are more demanding technically both for clinician and in the

technically both for clinician and in the laboratory

(50)

F

F

ull Cast

ull Cast

M

M

etal Crow

etal Crow

n

n

s

s

F

F

ull Cast

ull Cast

M

M

etal Crow

etal Crow

n

n

s

s

The preparat

The preparation for a ion for a full cast metal crownfull cast metal crown is more conservative than for a m

is more conservative than for a metal ceramicetal ceramic crown (0.5-1.0 mm compared with

crown (0.5-1.0 mm compared with 1.0-2.0 mm).

(51)

M

M

etal

etal

M

M

etal-

etal-

-Ceramic Crow

-Ceramic Crow

Ceramic Crow

Ceramic Crow

n

n

n

n

s

s

s

s

Metal-cera

Metal-ceramic cmic crowns are generally usedrowns are generally used when a patient requires a more aesthetic when a patient requires a more aesthetic restoration. Porcelain can be used on the restoration. Porcelain can be used on the visible surfaces, such as the buccal and visible surfaces, such as the buccal and

occlusal surfaces of mandibular teeth. If the occlusal surfaces of mandibular teeth. If the clinical crown height is

clinical crown height is small, then retentionsmall, then retention grooves are cut in the core to provide added grooves are cut in the core to provide added retention

(52)

Ceramic Crow

Ceramic Crow

n

n

s

s

Ceramic Crow

Ceramic Crow

n

n

s

s

Occasionally it is reasonable to use a Occasionally it is reasonable to use a casta

castableble or higor high-streh-strengtngth ceramic crh ceramic crown oown onn a posterior tooth, if occlusal factors

a posterior tooth, if occlusal factors are notare not inhibitive. The amount of tooth reduction is inhibitive. The amount of tooth reduction is more than with a

more than with a metal-ceramic crownmetal-ceramic crown (occlusal reductio

(occlusal reduction of 2 n of 2 mm) and mmm) and mayay compromise retention

compromise retention, , especially in teethespecially in teeth with a short crown height

(53)

Temporary crow

Temporary crow

n

n

s

s

Temporary crow

Temporary crow

n

n

s

s

F F

or a

or a

nn

terior 

terior 

Polycarbonate and acrylic temporary crown Polycarbonate and acrylic temporary crown forms Custom-cast temporaries.

forms Custom-cast temporaries.

F

F

or posterior teeth

or posterior teeth

Metal shell crown forms Metal shell crown forms  Custom-c

 Custom-cast temporariesast temporaries 

 LLong-term temporaries, metal-acrylic andong-term temporaries, metal-acrylic and

metal-composite crowns metal-composite crowns

(54)

F

F

F

F

ull metal ve

ull metal ve

ull metal ve

ull metal ve

n

n

n

n

eer crow

eer crow

eer crow

eer crow

n

n

n

n

A

Add

va

va

nn

tages

tages

1.

1. SStrong, rigid and wear resistanttrong, rigid and wear resistant

2.

2. High resistance & High resistance & retentionretention

3.

3. FFairly conservative prepairly conservative prep

4.

4. Uncomplicated prepaUncomplicated preparation & ration & marginsmargins

5.

(55)

D

D

isadva

isadva

n

n

ta

ta

g

g

es

es

D

D

isadva

isadva

n

n

ta

ta

g

g

es

es

  EE

sthetics

sthetics

 ±

 ± SSome patieome patients dislike and will nts dislike and will stronglystrongly

object to the full metal cover  object to the full metal cover   ±

 ± May bMay be limite limited to ed to uppupper and loer and lower wer  molars and lower premolars

molars and lower premolars

Galvanic action

Galvanic action

 ±

(56)

 A

 A

 Advantage

 Advantage

dvantage

dvantage

s of

s of

s of

s of

composite

composite

composite

composite

fiber post

fiber post

fiber post

fiber post

 Can bonded to the tooth with resin cementCan bonded to the tooth with resin cement

 ModuluModulus of elasticity s of elasticity similar to dentinsimilar to dentin

 EEase of removal for ase of removal for retreatmentretreatment

 EExcellent estheticsxcellent esthetics

(57)

The

The

ole of 

ole of 

P

P

osts i

osts i

n

n

the

the

estoratio

estoratio

n

n

The

The

ole of 

ole of 

P

P

osts i

osts i

n

n

the

the

estoratio

estoratio

n

n

of 

of 

E

E

n

n

dodo

dodo

n

n

tica

tica

lly T

lly T

reate

reate

d T

d T

eet

eet

h

h

of 

of 

E

E

n

n

dodo

dodo

n

n

tica

tica

lly T

lly T

reate

reate

d T

d T

eet

eet

h

h

The primary purpose for a post is to retain a The primary purpose for a post is to retain a core that can be used to support the final

core that can be used to support the final restoration.

restoration.

Posts do not reinforce endodontically treated Posts do not reinforce endodontically treated teeth, and a post is not necessary when

teeth, and a post is not necessary when

substantial tooth structure is present after a substantial tooth structure is present after a tooth has been prepared.

(58)

I

I

I

I

 N

 N

 N

 N

DDDD

I

I

I

I

CA

CA

CA

CA

T

T

T

T

I

I

I

I

OOOO

 N

 N

 N

 N

SSSS

Post placement is indicated if 

Post placement is indicated if bothboth of theof the

following clinical conditions exist: following clinical conditions exist:

 The remaining coronal tooth structure isThe remaining coronal tooth structure is

inadequate for the retention of a inadequate for the retention of a restoration.

restoration.

 When there is sufficient root length toWhen there is sufficient root length to

accommodate the post while maintaining accommodate the post while maintaining an adequate apical seal.

(59)

I

I

deal tooth

deal tooth

prepar

prepar

atio

atio

n

n

for post

for post

I

I

deal tooth

deal tooth

prepar

prepar

atio

atio

n

n

for post

for post

 placeme

 placeme

n

n

t

t

 placeme

 placeme

n

n

t

t

(60)

F

F

errule

errule

E

E

ffect

ffect

F

F

errule

errule

E

E

ffect

ffect

The ferrule is the circumferential ring of  The ferrule is the circumferential ring of  sound tooth structure that is enveloped by sound tooth structure that is enveloped by the cervical portion of the crown

the cervical portion of the crown

restoration. A minimum sound dentine restoration. A minimum sound dentine height of 1.5-2 mm is required between height of 1.5-2 mm is required between the core and crown margins.

(61)

Figure

Updating...

References

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