Prosthodonticsdd2011-2012.pdf

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Complete Dentures

The

shape and

amount

ofthe distobuccal

extension

of

a complete

mandibular

edentulous impression

is

determined

during

border rnolding by

the:

Ramus

of the mandible

Position

and action

ofthe

masseter

muscle

Lateral pterygoid

muscle

Tone

ofthe

buccinator muscle

Size

and location ofthe

buccal

frena

1

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border

molding

a

mandibular custom

tray that will be used for

a final dmture

impression:

.

The distobuccal extension

is determined by

the

position

and

action ofthe

masseter muscle.

.

The

distolingual

extension is limited by

the

action

ofthe

superior constrictor

muscle.

.

The buccal vestibule:

proper

extension

into this area

provides

the best

support

for the mandibu-

lar denture. This area

is refened to as the buccal shelf.

. Lingual frenum:

the proper borders

must

be established

with

movements

ofthe

tongue when

bor-

der molding.

The

genioglossus

muscle influencs

the lengdr ofthe flange during

normal movements

of the tongue.

.

The mentalis muscle

will

elevate the

mandibular

antrior labial arer unless

this border is estab-

lished

by accurate

border molding.

.

The retromol.r

pad:

marks the distal

termination ofedentulous ddge. This structure

needs to be cov-

ered for support and

retention.

.

The mylohyoid area: the flange in this ara

must accommodate the movemnt

ofthe mylohyoid

muscle in swallowing.

.

The retromylohyoid area: this area

is limited

posteriorly

by the action ofthe

palatoglossus

muscle

and

inferiorly

by

the lingual slip ofthe superior

constrictor muscle.

The

palatoglossus,

superior

pharlalgeal

constrictor, mylohyoid,

and

genioglossus

muscles

influential in molding

the lingual

border

ofthe mandibular impression

for an edentulous

patient.

The

most important consideration in checking

custom trays

for

accurate

border molding

is

and lack of displacement.

The

custom

tray for a

final

mandibular or

maxillary

complete denture

impression should have a

with stops to insule that th

tray

will

be seated

in

proper

relationship

to

the arch and that there

be

adequate

room for the impression

material. The space is created with

wax

covered

by aluminum

over the master cast

pdor to forming the tray.

primary

difference between border

molding with

a

ZOE impression matcrial and

border molding

modeling

plastic is that the

zoE

impression material must be

border

molded during one inser-

and within

the

setting

time of the mate al

-as

opposed

to two insertions with

modeling

com-


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To

increase the

capacity

of

underlying

struchrres

to

withstand

the

stress

due

to biting

force

and to improve appearance

To

provide

balanced occlusion and to increase tongue

space

To increase the capacity

of

the

underlying

structures

to

withstand the stress due to

biting force and

to

increase the effectiveness

ofthe

seal

To improve retention

and to

increase

tongue space

Copyrighr O

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I

month and 3 months

post

extraction

4

months and

7

months

post

extraction

5

months and

l0

months

post

extraction

I

year

and 2

years post

exhaction

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Key

point

-

undcrcxtcnsion ofthc

pcriphcral

bordcr ofa complctc

mandibular dcntrrrc dccrcascs tissuc-bear-

surfaccs, lhcrcby affccting dcnturc stability.

Merked ridge resorption will occur ifa mandibular complctc dcn-

base terminates

short

ofthc rctromolar

pad-

basal bote

(be

eath lhe

retromoldrpdd)

is rcsistant

lo

rcsorption. Covemge

ofthis

arca

will

also

some bordcr seal- An overload ofthe mucosa

will

occur iflhc bascs covcring

thc area are too smali in oul-

Mandibular denn[cs do not rely on suction from a

pcriphcral

scal for

retention

/ds

do marillary den-

but rather on dcnturc stabiljty in covcring

as

much

basal bonc

as

possiblc

$ithout i'rpinging on thc musclc

Thc active bordrmolding

perfonned

bythc lips, chccks,

and

tonguc determines the

peripheral

areas

mandibular arch, thus establishirg ma{imal basc bonc covcrage.

structurcs ofthc mrndibular

dcnturc:

Mandibular

lnterior

labial area: thc action of the mentalis musclc and the mucolabial

fold dctcrmincs thc

cx-

ofthe denture flangc

jn

lhis arca.

Mandibular labial frenum: lhis band offib.ous conncctive tissue hclDs attach thc orbicularis

oris musclc. Thc

ofthis

s(ructurc limits thc cxtcnsion ofthc dcnturc bordcr. thc thickncss oflhc

dcnturc basc, and aflects thc

olthc mandibular

tccth.

Buccal vestibule: is infiucnccd

by the buccinator musclc which has musclc fibcrs that run

in an

obliquc dircc-

and thcrcforc bave littlc displacing aclion- Propcr cxtcnsion into this arca

provides

the

best

support for thc

Tlis

arca

is

rcfcrred to

as

thc

buccrl shelf.

:|Iasscter

area:

thc

dcnturc

is limited in a latcral dircction by lbc action ofthc massctcr

musclc.

Retromolar

padi

marks

thc

distal

termination ofcdcntulous ridgc. This structurc nccds to bc covcrcd

fbr

sup-

and rctcntion. By doing lhis thc intcgrity ofbonc in lhis arca is maintaincd and

allows for support.

Lingurl frenum:

thc

proper

bordcrs

must

bc cstablished

with movemcnts ofthc longuc whcn

bordcr molding.

gcnioglossus

musclc

inlluenccs lhe length

ofthc

flangc during normal movcmcnts

ofthe

tongue.

Sublingual

gland

sreai maximum cxtcnsion dcsircd without ovcrcxtcnsion.

\ll

lohtoid

area: thc flangc in this

arca must

accommodatc

the

movcmcnt

ofthc

mylohyoid

musclc in

swallow-

Retromllohloid area:

this area is limitcd

posteriorlyby

thc action ofthc

palatoglossus musclc and inferiorly by

lingual

slip

ofthc superior constrictor musclc. Ifthcsc

musclcs

arc

impingcd upon, thc

paticnt

may

dcvclop a

throat. Notei This

is often ahc most diflicult are to manaqc.

of

the

healing ridge

progresses

rapidly for

four to

six

months

and does

become stable

in fonn until

l0

-12

months

post

extraction.

Due

to

this, immediate

become

progressively more

ill-fitting.

They

should be

relined

five

months and

months after delivery

in order

to compensate for contour changes.

Note:

This is a

gen-

each

case

needs

to

be

evaluated

monthly

and,

if

necessary,

relines

is indicated

on any denture

when the diagnostic

information

indicates that a re-

rvill

effectively

solve

the

patient's

chief complaint

-

when

the denture

base

is

the major defect

in the

prosthesis.

A reline

is

contraindicated

when there is

overclosure of

the

vertical dimension

-

a

large

decrease

in

veftical

In

this

case,

new dentures are

indicated

at the

proper

vertical

dimension.

When

a

patient

wears a complete

maxillary

denture against

the six

urandibular an-

teeth,

it

is very common

to

have

to

do a

reline every so often due

to the loss

of

in

the

anterior

maxillary

arch

-evidenced

by a flabby

maxillary

anterior


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3 hours

aiier delivery

12 hours

after delivery

24 hours

afier

delivery

48

hours after delivery

Coplrishr O 20ll-2012 - Denral Deck

Gagging

Cheek

biting

Reduced taste

Speech

aberrations

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is

done

for

the

purpose

of

correcting undetected enors. Tissue

trauna

attributed to

function

manifests as h)?eremia, inflammation, ulceration,

and

pain.

basic

sequence

ofthe clinical

procedure for

a

24 hour recall appointment

is:

l.

Remove the dentures

from the mouth.

2.

Thoroughly

examine

the mouth.

3. Ask the

patient about the areas

oftissue

trauma which have been

obseryed.

4.

Pemit the

patient to describe additional complaints.

After

collecting

all

ofthe

diagnostic information, the dentist

can determine the source

problem

and

the cure.

the

first few

days

following

the insertion

of

complete

dentures, the

should

expect some

difficulty

in masticating most foods and excessive saliva

-

is

due

to

reflex

parasympathetic

stimulation

ofthe

salivnry

glands. Over time this

subside and become normal.

Occlusal

disharmony can be

most accurately

corrected on

the

articulator

patient remounting

procedures.

Reduce

the

facial

surfaces

olmandibular

molars to

create

proper

horizontal overlap

teeth edge

to

edg

Reline at

corrected

VDO,

patient remount,

fabricate

new denture

vertical dimension

comers

of the

mouth

l. Lip

biting

may be due to reduced

muscle tone and/or

a large

anterior

hori-

zontal

overlap.

2. Tongue

biting

may be caused by

having

posterior teeth

too

far lingually.


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Facial

to the ridge

Lingual

to the ridge

Exactly over the ridge

lncisive

foramen

Palatal

mucosa

Hamular

notch

Posterior

palatal

seal

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A

patient

who wears a

complete

msxillary

denture complains of

a

burning

sensation in

the

palatal

area

of

his/her

mouth.

This

is

Indicativ

oftoo

much

pressure

bcing exerted

by the

denture

on

the:


8/172

teeth directly over

the

ridge

usually

causes

poor

esthetics

of

dentures.

is important to have accurate adaptation

ofthe

border seal and adequate

bulk

of

maxillary facial

flange

for

good

esthetics.

Vertical

dimension ofocclusion affects the

support as

well.

most

patients,

the labial surface

ofthe

central incisor should be approximately 8

mm

to the center

ofthe incisive

papilla.

The labioincisal

onethird ofthe maxillary

incisors should support

the lower

lip

when the teeth

are

in occlusion.

The long ares

of

the

maxillary

central incisors

should be

perpendicular

to

plane;

the long axes

of

the

maxillary

lateral incisors should

have an asyrn-

central

incisors

are

the most important teeth when esthetics is

Their

placement

controls the midline, speaking

line,

lip

support and

line

composition.

Note:

Placement

of

maxillary

anterior

teeth in complete den-

too far superiorly and anteriorly

might result in

difficulty

in

pronouncing "f'and

"v"

ofthe

common

errors

in the arrangement

ofteeth include:

.

Setting mandibular anterior teeth too

far forward

to

meet the

maxillary

teeth

.

Failure

to make canines the

tuming point

ofthe

arch

.

Setting

the mandibular first

premolars

buccal to the canines

.

Establishing the occlusal

plane

by

an

arbiirary line on the

face

.

Not

rotating anterior teeth enough

to give

an

adequately narrower effect

1. A burning

sensation in the

mandibular anterior area

is caused by

pressure

on

the mental foramen.

2. A

patient having

trouble swallowing

may have

insufficient

interocclusal

space

-decreased

freeway space

caused

by excessive

vertical dirrension

oloc-

clusion.

3. The best

dietary advice

for

an

elderly denture

patient

is to eat

foods rich

in

protein

and

vitamins

A,

C,

D,

and

B complex.

Leaming

to

chew satisfactorily

with new

dentures

requires at

least 6-8 weeks.

time is spent on establishing

new memory

patterns

for both

facial and

masticatory

ridges

can be

ruined by

the use of

denture

adhesives

and

home-reliners.

patients should be specifically

warned

about their uses.

These agents can

mod-

the

position

ofthe denture

on the ridge and result in change

ofboth

vertical and cen-

relations.


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The

trNtment

plan

for

a

patient

indicates

thst both

manilibular

and

maxi.llary

immediate

dentures are to

be

fabricated.

The

ideal wav to do

this

is:

Fabricate the

maxillary

immediate denture

first

Fabricate the

mandibular immediate

denture

first

Fabricate the

maxillary and

mandibular

imrnediate dentues

at the same time

8

Coplright O

201

I 201?, Denial

Decls

The

first

step in the

treatment

of

abuseat tissues

in

a

patient

with existing dentures is

to

abricate a new set ofdentures

eline

the dentures

ducate the

patient

xcise the

abused

tissues

I

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main

reason

for this

is

to avoid setting the

maxillary

teeth to the

likely

malpositions

the remaining mandibular teeth

master casts are altered in an immediate denture

procedure

(e.g.,

elim-

ofgt"oss

undercuts),

it

is advisable to construct a second denture

base that is trans-

(called

a surgicol

stent or template). This surgical stent is

placed over the

ridge after

are

exhacted.

Pressure

points

and undercuts are readily

visible

and

surgical ridge

can be

performed.

The

duplication

ofthe master cast used

for

the construction

ofthe

surgical

used at

the time

of

immediate denture insertion

is

best

rnade after wax

and after

the

cast

is

trimmed.

A major

advantage

with

immediate

dentures

is being

able

to

duplicate the

of

the

natural

teeth.

The

patient

should understand

both the cause

ofthe

tissue

deterioration

and

ifthe

process

is not arrested.

plan

for tissue

rcovry from abused tissues:

.

Educat the

patient

.

Remove the dentures:

at least for 24 hours or

until

the tissues

retum

to normal size,

shape, color, consistency, and

texture. Note:

Ifthe

constant

wear

ofunacceptable

den-

tures

is the cause

of

the tissue abuse, the most

efficient

preliminary

treatment

is re-

moval

ofthe

dentures.

However, business and social commitments

may not

permit

removal for extended

periods. In such

patients,

resilient tissue

conditioning materi-

als may be used to assist

in the tissue recovery

program.

.

Have the

patient

clean

the

dentures: with a

sofi

brush and

no abrasive agents.

They

should

be

instructed

to

soak

the dentures

for

at least 30 minutes

in

a

commercially

available denture disinfectant solution.

.

Ifpatient

has

a Candida

albicans

infection

(either

generalized or angular

cheilitis):

should be treated by

using nystatin oral rinses for

generalized infection and

nystatin

h|ith

tridmcinolone

acetonide)

cream

for

angular

cheilitis.

.

Resilient tissue conditioning

materials

may be needed to assist

in the tissue recov-

ery program.

procedures

recommended

as aids in the treatment ofabused

tissues

include

mas-

and warm saline

rinses.


11/172

The psychological

comfort

ofavoiding the loss

ofall teeth

The

continuous functional feedback for

the neuromuscular

system from

proprioceptors

in the

periodontal

membrane

The preservation

ofthe alveolar

ridge

The

improved

support and stability for the

denture

The

increased retention ofthe

denture

10

Coplaiglit O

201

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Linguoalveolar

sounds

or sibilants

(such

as s,

z,

sh, and ch)

Fricatives

or labiodental sounds

(such

as

f,

v, or

ph)

B,

P, and M sounds

Linguodental

sounds

(such

as this, that,

or

those)

'11

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overdenture

is a

denture whose base is constructed

to

cover

all

ofthe

existing resid-

selected

roots. Retained roots help to

prevent resorption

of

the alveolar

These roots also improve retention and

afford

the

patient

some

proprioceptive

of

"natufalness"

in

function

ofthe

dentures.

is

not

always necessary to cover

a root beneath an overdenture,

however,

ifa

root

is

the exposed surfaces are

highly

susceptible

to

decay,

The oral hygiene of

patient must

be

impeccable to

prevent the decay ofthese roots.

Retained roots

are

the most common

findings

when

taking

routine

panoramic

of

patients

who wear

complete dentures

(rol

necessarily

overdentures).

The

general

rule for

retained

root tips with

no

radiolucency

and the

corti-

margin

ofbone

intact is that they can

remain in

place;

however,

the

patient

should

informed oftheir

presence.

They

should

be

removed

if

the cortical

plate

is

perforated

PDL or

radiolucent area is

getting larger

sounds

in the complet denture

patlent:

.

Frictative or labiodental

sounds

(f,

v,

and

ph):

are formed between

the

maxillary inci-

sors contacting the

weVdry

lip

line of

the mandibular lip. Note:

These sounds

help

deter-

mine the

position

ofthe

incisal edges

ofthe

maxillary anterior

teeth.

.

Linguoalyeolar

sounds

or

sibilants

(s,

z,

sh,

ch,

and

j):

arc

made

with

the

tip

of

the

tongue and the most anterior

part

ofthe

palate

or

lingual surface

ofthe

teeth.

Note: These

sounds help determine

the vertical

length and overlap

ofthe

antedor

teeth.

Important: A

whistling sound with dentures

is

indicative ofhaving

a

posterior

dental

arch form that is

too

narrow

or

high.

.

Linguodental

sou nds

(this,

that, and

those,),'

the tip of

the tongue should

protrude

slightly

between the

maxillary

and mandibular anterior

teeth. Note: These sounds

help determine

the

labiolingual

position

ofthe

anterior teeth.

.

The b,

p, and m

solnds: are

made

by

contact of the lips.

Not:

Insuficient

lip

support

by the teeth or the

labial

flange can affect the

production

ofthese sounds.

The

two most

probable

causes

of

a

patient

complaining

that whenever

he/she tries to

"s" sound.

it sounds

like

"th"

are:

.

lncisor

teeth

are set

too far

palatally

.

Palate is made too

thick

To evaluate

vertical dimension,

have

the

patient pronounced the s sound; the in-

should

be I

to

1.5

mm. This is known as the closest

spaking space.

.

Ifthe

teeth are

positioned too far lingually, the "t" will

tend

to

sound

like

a

"d."

Ifthe

teeth

are

positioned

too

far labially, the

"d"

will sound

more like a

"t."

.

An increased occlusal

vertical dimension can

result in

clicking

ofteeth.


13/172

.

The

primrry

role ofanterior leeth

on a

denture

is:

To incise

food

Occlusion

Esthetics

Stability

of the denture

12

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201l-2012, Denral

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Fibrous tuberosities

Too

great

a

vertical

dimension

ofocclusion

A lack

ofposterior

occlusion

The

maxillary

denture teeth that were

used are too short

13

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lapping, rotation,

and

color

changes can bejudiciously used

to create

a

natural

Note:

Proper

lip

support

is

provided

by

the

facial

surfaces

of teeth

and

attached

gingiva.

the anterior

teeth either too far lingually or

facially to

satisfy esthetic

concems

not

be

done. When selecting teeth,

pre-extraction

records

are

very valuable.

and

mandibular anterior teeth should

not

contact

in centric relation.

outline

ofanterior

teeth should

harmonize with

the

form

ofthe

face:

. Convex profile faces should

have a

similarly

convex labial

surface

ofanterior

teeth

.

Broader contact

areas

ofteeth

look more natural on dentures

as they seem

more

com-

patible

with advanced age

when

a

patient speaks

with

dentures

(complete

or

partial wltich replaces the

may be caused by any

ofthe

following:

.

Vertical

overlap

is not enough

.

Horizontal

overlap

is

too

much

.

The

area

palatal

to the

incisors is improperly

contoured

(too

high

or too narroh,)

general,

functional

needs

overshadow

those ofesthetics

when selecting

pos-

teeth. Do

not set

mandibular molars over the ascending

area ofthc

mandible

occlusal

forces

in

the

area will

dislodse

the

mandibular

denture.

patient's

chiefcomplaint

will

be

looseness ofthe maxillary denture.

Thcy

will

also state thal they

no longer see their upper teeth on

the denture. These signs and symptoms

are caused by a lack of

occlusion.

A

patient

wearing a

maxillary

complete

denture and a mandibular

bilateral

distal-ex-

partial may show:

.

Decreased vertical dimension

ofocclusion

.

A prognathic facial appearance

\\ftcn

a complete

maxillary dcnture opposes natural

mandibular anterior tecth.

the marillary tn-

ridge

often

becomes very

flabby.

The best impression

technique for an edentulous

patient

with

loose,

h)?erplastic

tissue

in

maxillary anterior

region is to register the tissue in its

passive position.

.

1.

Denture support

refe$ to rcsistance to vertical seating forces.

2. Denture stability

is necessary to resist dislodgement of a dcnture

in the horizontal direc-

tion.

l. D"ntu."

."tertion

is the

ability ofthe

denture to

withstand dislodging

forces exerted in the

venical

plane. Surfaces of a denture that

play

a

part

jn

retention:

.

Intimate

contact

ofthe

denture

base

and

its

basal

seat

.

Teeth: no occlusal

prematurities

to break rctention

.

Dsign of the labial, buccal,

and lingual

polished

surfices: configuration

harmonious

with forces

generated

by thc

tongue

and

musculature

4. Factors that

influence

denture sudace:

.

Adherion: saliva to denture and to tissues

-primary

retentive force

.

cohesion

(the

attraction ofmolecules

lot

each other)

depends onr the area covc.cd and

the type of saliva

/i.e.

,

thick, ropy

-unfavorable;

thin, \,atery

-

better

retention)

.

Atmosphric

pressure: prcportionate

to area covercd and depends

on

pe pheral

seal

.

Mechanical: ridge size, shape, and inter-ridge distance


15/172

Adequate

coverage of tray borders

with the material

used for border

molding

Contours

ofthe

periphery

similar

to the final form

of

the denture

Stability and lack ofdisplacement

ofthe

tray in

the mouth

Uniformly

thick

borders

of

the

periphery

14

Cop)right O 201l-2012

-

Dental

Deks

Residual ridges

Palatal

rugae

Incisive

papilla

Maxillary

tuberosity

Buccal

vestibule

15

Cop)'righr O 20ll-2012, Dental

Decks


16/172

ease and accuracy

ofthe

border molding

depends

upon:

l.

An accurately

fitting

cuslom tray

2.

Control of bulk

and temperature

ofthe

modeling compound

3. A thoroughly dried

tray

fabricated on

the preliminary cast is

trimmed approximately

2 rnm short

the mucosal

reflection

and frenae.

This

is done

by first

checking

the

borders in the

and then trimmed

down. This

will

allow

a uniform thickness

of

2

mm

of

model-

compound

when borders

are

molded. Proper border

molding

results

in contours re-

the

final

form

ofthe

denture. However,

the

primary

indicator

ofthe accuracy

border molding

is the stability and

lack ofdisplacement

oftray

in the

mouth.

molding

is completed

in two

stages.

In

the lirst stage

the

molding

should ap-

the borders

but should

be

slightly overextended.

Excess compound

is trimmed

inside and outside

ofthe

tray. The remaining modeling compound

is

then refined by

the

process. The

final

form

ofthe

border molding

should

represent an accurate

ofthe

peripheral tissues. The modeling

compound should

have a

smooth,

al-

polished

appearance.

border

molding

is cornpleted,

some areas

ofthe

modeling compound

should be

re-

because

the tissues

are

extremely

displaceable and

have

probably been distorted

the border

molding

process. These areas

include

around

the

maxillary

labial

and

over the

retromolar

pad

areas.

Modeling compound

(plastic)

has a relatively low

thermal

conductivity.

The

primary

support

areas of

the maxillary complete denture

are thc residual

ridges

(the

and

palatine

bones),

In the

mandibular

arch, the

primary

support area

is the buccal shelf

because of its

and its

right anglc relationship

to the occlusal

plane.

Proper extension

into this area

ecessary-

to

more

widely distribute

the

load

ofmastication.

The residual ridges

iflarge

and

broad

also

be considered

as

lhe

primary

suppofl areas.

structures oflhe

maxillary denture:

.

ln

the

anterior

region: the labial

vestibule, which cxtcnds from

the right buccal

frenum to the

leil

laterally, from

the right and

lcft

buccal

vestibules extending in the

posterior

aspect on each

side to the right and

left hamular notches,

respectively.

.

The

posterior

limit: extends

to

junctions

of moveable and

immovable tissue.

This coincides

'$'ith

a

line drawn through

the hamular notches and approximately

2 mm

posterior

to the foveae

palatiJle

(vibrating

I ine).

.

The secondary

peripheral

seal arca for a mandibular complete

denture

is thc anterior lin-

gual

border

.

Ifyou

are

labricating

a

mandibular complete

denture for a

patient with a knife-edge

ridge,

you

need maximal extension

of the denturc to help distribute

the

forces

of

occlusion

over a

Iarger arca

The most important

factor for

providing

retention

for complctc dentures

is the

pe-

seal.


17/172

\-

An overertended distobuccal

corner of

a

mandibulrr

denture

will

push

agrinst which

muscle during function?

Zygomaticus

Orbicularis

oris

Temporalis

Masseter

'|6

Coplaighr

e

20ll'2012 - Dental

Decks

After border molding

the mandibuhr

custom

tray, it is important

to

check

for

dislodgement

in order to

detect areas

of:

Underextension

ofthe

tray

Overextension

ofthe

tray

Thickness

ofthe

tray

None

ofthe

above

CoDright O

201

I 2012, Denial

Decls


18/172

is

a

very

common

area ofoverextension and should be checked

very well when de-

the mandibular

denture.

buccinator

muscle lies under

the

denture

flange

in

this area but

the fibers run an-

in a horizontal

plane

and

their

action is weak; the

anterior

fibers

of

the

muscl

pass

outside

the buccinator at the distobuccal comer

ofthe mandibular

and

will

push against the

buccinator

during function causing

dislodgement.

When the

posterior

maxillary

buccal space is entirely

filled

with

the den-

the

coronoid

process

may

interfere with

the

denture

upon

opening

of

the

This will cause dislodgement

olthe

maxillary

denture.

L

The superficial

layer

ofthe

masseter muscle originates

from

the

zygomatic

process of the maxilla and

inserts at the angle and

lower

lateral side

of

the

ramus

of

the mandible.

2. The

pterygomandibular raphe

lies between the

buccinator and superior

constdctor

muscles.

for dislodgement

using

the following

techniques:

.

Pull

gently

upward

on the

patient's

cheek

.

Pull

the

lower

lip

gently forward in a horizontal direction

.

Have the

patient open

widely

.

Have the

patient move the

tongue

into

the

right

and

leit

buccal vestibules

.

Have the

patient

protrude

the tongue

to touch the lower lip.

Have the

patient move the

tip ofthe

tongue

from one corner

olthe

mouth to the other

indicates

overextnsion and the border

molding

process

should

be

refined

the offending area.

Common areas

ofoverextension

ofthe mandibular

impression are

labial

and

the truccal. This is suspected

when the impression

raises

as

the mouth is

most critical

area

in the

border-molding

procedure

for

a

maxillary

denture is the

fold

above the

maxillary tuberosity area.

This

area

is

extremely

important

retention.

Other

critical

areas are

the

labial

frena

in

the

midline

and the

the bicuspid

area. Overextension

in

these areas often

leads

to

decreased

reten-

and tissue

irritation.

Pressure areas

on the impression surface

ofdentures is checked

with

PlP.

Use dig-

pressure

only,

one denture at a

time. Special attention

should

be

given

to

the

hard

and the

mylohyoid

ridge

areas.


19/172

The

inclination ofeach condyle

Vertical

dimension ofocclusion

Centric

relation

Location

ofthe

hinge axis

point

Maintain the vertical dimension

of

occlusion

Maintain

bite

registration

Preserve

the

face-bow

transfer

All

ofthe above

t8

Copyright O2011,2012

-

Dental

Dcks

'|9

Coptrigir

@

201 1,201 2

,

Dnral Decks


20/172

face-bow is a caliper-like device used

to record the

patient's

maxilla

/ hinge axis rela-

(opening

and closing axis).It is also used

to transfer this relationship

to the ar-

the mounting

of

the

maxillary

cast. Ifthe face-bow

tratsfer

procedure

is

done, the arc

ofclosure on the articulator should duplicate

that exhibited by the

This

hinge-axis face-bow transfer enables

alteration in vertical

dirnension on

articulator

altering

vertical dimension

(either

through

restorations or

with dentures),

should be

mounted

on the hinge axis.

the maxilla,4ringe

axis relation is transfened

to

the

fully

adjustable

articulator, it

to obtain the

precise

tracing

of

the

paths

followed

by

the condyles.

A

is

an

instrument which carries out

this task

with

the help

of

two face-bows.

is attached to

the

maxilla

and the other to the

mandible using a clutch

that attaches

in their resDeclive

arches

dentures,

there are

two

methods

used to

preserve

the

face-bow

l.Taking a

plaster index

ofthe

occlusal surfaces

of a maxillary

denture

before

re-

moving

the denture

from the articulator and

cast

(see picture

below).

2. Placing

a

piece

of

10x

wax

on the occlusal surfaces

of the mandibular

teeth and

closing

the articulator

in

centric

relation.

Chill

the

wa.x,

drop

the incisal

guide

pin

to

touch the incisal

guide table

(do

not change).

The

plaster index method

is the

preferred

method due

to

possible

distortion

[tlaxillary

Oenture

Plastor

lndex

Cast


21/172

Faulty

tooth

position

Excess

vertical dimension

ofocclusion

Faulty palatal

contours

Faulty

occlusion

20

Cop}tiSh

O

201

I

-20 12

-

Dental Decks

The

newness

ofthe

denture

Defective

tissue registration

Premature

occlusal

contacts

lncornplete

polymerization of

the denture

base

21

Coplaighr

O

201

l-2012 -

Dentat

Deck


22/172

problcms

due to faulty

tooth

position

can

be

avoided by

placing

thc dcnturc

tccth as close as

possible

to thc

ofthc natural tccth.

Note: Thc most cffcctivc timc to lcst for

phonctics

is at thc timc oflhc

wax try-in

oithc

frlrr

rs

l/s d

f

thefourth appointmett).

Faulty

palatal

contours can bc co.rcctcd by

trial and crror Add

to

incrcasc contours

and rcducc

as

nccdcd to improvc articulation ofsounds.

Note: Paticnts

who have

becn eden-

many

years

oficn

havc more distorted spccch than thosc \r'ho havc bccn cdcntulous

lbra shorllimc. This

to

a

loss

oftonus

ofthc tonguc musculaturc.

the

first

appointment

after insertion ofcomplete

dentures, the

presence olgeneralized

on the crest

of

the mandibular

ridge

is

most

likely

due

to

improper

occlusion

occlusdl

contqcts).

To

identify

these, the best

method

in

the

mouth is to

use

wax that

is

slightly

warmed.

Insert the wax

bilaterally

and bave

the patient

into centric.

The

prematurities

will

show up

as

windows in

the

wax'

Once

centric

complete, be sure

to check eccentric

movements.

Acrylic

spicules, inaccurate

denture bases and trapped

food can

all cause

ul-

as

rvell. Ifan acrylic spicule

is found,

it

should be

reduced. Ifan

inaccurate denture

is suspected,

it

should be relined.

-

.

-

1. After

relining

dentures, ifa

patient constantly retums

for adjustments

due

to

sore

spots on the

ridge,

check

the

occlusion.

The relining

procedure may have

changed

the centric

relation contacts.

2. Errors in occlusion

may be checked

most accurately by

remounting the den-

tures on

the articulator using

remount

casts and new

interocclusal

records.

Remember: Casts

mounted

with

an interocclusal

record are

mounted more ac-

curately if

the

material used is selected according

to the accuracy

of

the casts

bing

articulated

(casts

produced

with

iteversihle

hydocolloid

are more accu-

rateb) mounted

with

wtu

records, and casts obtained

with elastomeric

materi'

sls

are more accurately

mounted

with

elsstomeric

registration

materials or

zinc

and

eugenol

paste).

maxillary

ccntral incisors

to

irnpcde $e ail stream

parsing

btwen

ilE tonge

aDd

pal-

ate.

Crcat rugae ifnecs3sry

An

sbcam

passcs

unimpcdcd

or

with inadequate impcdancc

bclwcen lhe dorsal surface

of

thc torgrc and lhc ani,crior

pal-

The

an strcam

passing

bctwccn

tle tongue and intc.iorpalalc is

cxccssivcly impcdcd. usually

by njgae or xcessiv

resin

Rcduco occlusal verlical

dimension u il

prcmolars

no louer con&ct during

Reduce

oc.iussl

vrlical

dineDsion unril

premolas

ro

longer contacl

during

Maxillary

&

Mandibular

ircisots or

p.emohrs

conta.t

during

sibilsnl

/r

s/,,

z

cr)

Eval a& Iip suppod and

overall apperance of anterior

terh as

dley

ar

positiood.

Reset

to a more

lingual

posr-

tion

as

need.d-

Incisal edge

of

maxillary

incisors lhould con-

racl thr wat/dfy

junciion

Just

lingual

to

it

during

producrion

olthe

"F'&

"V" sounds

Cliniciar

obs'ves

that incisal

dg6 of

naxillart incisors

co

act lhe lower

lip

I mm or

moE labial

to lhe

wet/dry

of lower lip when

"F

'

& "1f'lomds

are nade

Maxillary

teetl mal

be

sct loo

far labially


23/172

Frankfort's plane

Camper's

line

Fox

plane

Horizontal condylar inclination

22

Copright O 20l l-2012 - Dntal D4ks

Insufficient pressure

on the

flask

during

processing

Insumcient

material in the mold

A rapid elevation in temperature

to 212' F causing

vaporization

ofthe liquid

insufficient time for

processing

23

Coplrighr O20ll-2012

-

Dental Dcts


24/172

are

the resultant

product

after

adding base

plate

wax to

a

record

base

order to approximate the tooth

position

and arch form expected

in the completed den-

rims are used

to:

.

Determine and establish the vertical dimension

ofocclusion

.

Make maxillo-mandibular

jaw

records

.

Establish

and

locate the future

oosition ofthe

artificial teeth

l.

A

good

slarting

point for

determining

the vertical length

ofthe

maxillary

oc-

clusion

rim

is a

point

approximately

2

mm below

the

upper

lip

when

it

is re-

lared.

2. When recording

centric relation

for a removable

partial denture, the occlu-

sion

rirn should

be

attached to

the

completed

partial

denture framework

in-

stead ofa

record base as used

with

a complete

dentue.

3.

Ifat the tooth

try-in

appointment the teeth need to be adjusted

to correct the

centric occlusion,

the best way to do this is to take a new centric

relation

record

and remount.

resin used for

denture repairs should

be under 20-30

psi

air

pressure while being

to

help eliminate

porosities. These

porosities, ifpresent,

will usually occur

in

thickest

part

ofthe

denture. Self-cured

resins are

generally used

for repairs instead

resins because

the

risk

of distorting

the denture is

less.

l. When there

is

a

rapid elevation

in

temperature

causing

vaporization

ofthe liq-

uid,

the vapor

is

then trapped

as

gas

bubbles.

2. Porosities

will also occur

if

the

packing

and

processing

ofthe

powder

and

liquid

resin

is

too

pllstic

(stringl

or sandy/.

This

permits

the

liquid to vaporize

and,

at the same

time, does not

allow

sufficient

pressure during closure

of

the

flask.


25/172

Increased

post-insertion

care

Increased

post-insertion soreness

Not being able

to have an anterior

tooth try-in

to evaluate esthetics

Greater complexity

ofclinical

procedures

A higher cost

oftreatment

21

Cop).righr O

201

l-2012

-

Denlal

Decks

The face-bow

is a

caliper-like

device used

to

record

the

patient's

maxilla,/hinge axis

relationship

(opening

and closing

axis)

If

the transfer is

done

properly,

the arc

of

closure on the

articulator should duplicate

that exhibited

by

the

patient

The

face-bow transfer is a maxillo-mandibular

record

The

face-bow transfer

is

used

to

transfer the

maxilla/hinge

articulator during the mounting

ofthe maxillary

cast

axls

relationship to

the

25

Coplriglt C

201

l-2012 Dmtal Decks


26/172

of

immediate

dentures:

.Increased

post-insrtion

care, including relining or remaking the denturcs. Contour changes occur in

the healing residual ridge for 8-12 months.

.Incrersed

post-delivery

soreness.

The

combination of

post-extraction pain

and denture

related

trauma

often

produces greater

discomfoit during

the first few

days following insertion.

.

Greater complxity ofclinical

procedures.

Forexample, bordermolding and final

impressions

are more

difficult

when

natural teeth remain.

.

Higher total

cost of

treatment

Ther is an increased expense due to the need for relines and repeated

equi-

libration

of the occlusion.

of immediate dentures:

.

Continuously acceptable esthetics. Immediate

dentures

are

esthetically

advantageous in that the

palient

is never

without

either natural or

artificial

teeth.

Improved

speech

adrption.

Immediate

dentures rcquire only one

period

ofspeech adaptation,

whereas

onventional denture trcatment

requircs

two; one afierthe

teeth

are extracted and anothcr

after thc

dentures

re delivered.

Protection of the extraction sites frcm trauma, Denhrres

act as a

typ ofbandage over the clot filled sock-

ts.

Continuously acceptabl masticatory function. The

patient

retains some semblance ofchewing ability

uring the healing

process.

Prevention

oftongue enlirgement.

When naiural

teeth are lost and not

replaced, the tongue tends to ex-

into the available space.

help the

patient get

through the fiIst day ofwearing immediate dentures, instruct him to do

the

following:

.

Do not remove the dentures

.

Retum in 24 hours

.

Eal

soft

foods

ottooth rcmoval;

. First

stepi

extract

all posterior

teeth

except

a

ma-rillary first prcmolar

and its

opposing tooth. This

leaves

a

posrerior

"stop"

in

order

to maintain the vertical

dimension ofocclusion.

.

Second step: after the

posterior

rcsidual ridges exiibit accptable clinical healing,

the second

phase

of

rreament, that ofdenture

fabrication,

can begin.

The

anterior teeth will be extracted

at the

time ofdcnnrrc

lnsertlon.

This is false; it is a

record used to

orient

the

maxillary cast to the

hinge axis on the

T

=

Tragus ofear OC

=

of

the eyes

varieties

of

arbitrary face-t ows are available. All are

based on

an average lo-

ofthe

hinge axis

and

will

yield

an

enor

of2

mm or less in the majority

ofpatients.

rotational

centers are

generally located

over

measured

points

on

the face or

by

type

of

earpiece. One

average

measurement

(above

picture)

places the

rotational

13 rnm anterior

to

the distal edge

of

the

tragus of

the

ear' along

a

line from

the

center

ofthe

tragus to the

outer

canthus

of

the eye. The

condylar

styli

the

face-bow are

then

placed

directly over

the dots.

J

"",f

{.

;

"t

Outer canthus


27/172

Is placed

3

mm

posterior

to

the vibrating line

Is not necessary

when fabricating

a

complete denture

on a

patient

with a flat

palate

Is

not necessary

ifa

metal

base is used

Will

vary in

outline

and

depth according to the palatal

form

ofthe

patient

26

CopriShr

C

201

I

'l0l:

-

Dental Decks

Pterygomaxillary notch

Vibrating

line

Hamular

process

Fovea

palatinae

27

CopFighr O 201l-2012

-

Dnlal Deks


28/172

Posterior Palatal Seal

poslcrior

line

(A)

indicatcs th cnd of thc

posteriorly

across the

palate.

The

anterior

(B)

marks thc location

of the

posterior palatal

will b caRed

intothe cast and transfcrcd

bead onto

the denture.

The dcnture cnds on thc cast

at A. the bcad

(B),

locatcd 2

mm in front of the vibrating

line, is

extcndcd

latcrally

through thc ccntcr of

thc hamular notchcs-

Bolh

phoros

m Fprcduced

wnh

pmission,

fiom

zdb

GA,and

Bolender

CL..

Ptosthodontic

Tredhent

lot

Edertulow

Potients- Mosby,20,.J6.

posterior palatal

se|l

is completed before the final arangement ofthe

posterior

teeth because

this firal

a laboratory

procedure

and is done in the absence of the

patient.

The anterior

lilre that

indi_

the location ofthe

poste

or

palatal

sealis drawn on the cast in fiont

ofthe

line indicating

the

end ofthe

The

width ofthe

posteriorpalatal

sealitselfis

limited to a bead on the denture

that is

I

to 1.5 mm high

1.5

mm broad

rt its base. A

greater width

creates

an area oftissue

placement that

will

have a tendency

the denture downward

gradually

and

to

defeat

the

purpose

ofthe

posterior palatal

seal

ln other words,

posterior palatal

seal

should not be made too wide.

'-sh|ped

grcove

I

to

1.5

mm

deep

is

carved

into

the

cast at

the

location

ofthe

bead.

A

large, sharp

scmper

to carve

it,

passing

through the hrmuler

notches and across the

palate

ofthe

cast. The

$oove

will

form

on the denture that

prcvides

the

posterior palatal

seal.

The

bad

will be I to

1.5 mm high, 1.5 mm

at its base, and

sh|rp

tt

its apex. The depth ofthe

grooves

will

be

determined by

the thickness ofthe

tissue against which

it is

placed

and will establish $e height of

the

bead.

for Posterior

Palatal

Seal

.

The

posterior

outline

is

formed by

the

"ah"

line or

vibrating

line

and

passes

though

the two

pterygom xillary

(hamrlay'

notches and is close

to the

fovea

palatini.

.

The

anterior outline

is formed by

the

"trlow"

line and

is located at

the

distal extent

of

the

hard

palate.

Excessive depth

ofthe

posterior

palatal

seal

will

usually

result

in unseating

ofthe

The

posterior

palatal

seal will

vary in

outline and

depth

according

to

the

form

of the

patient.

the

Posterior

Palatal Seal:

.

Completes

the border seal

ofthe

maxillary denture

.

Prevents impaction of

food beneath the

tissue surface

of

the denture

.

Improves the

physiologic retention

of

the denture

.

Compensates

for shrinkage

of

the denture resin

during

processing


29/172

Deepening

ofnasolabial

groove

Loss

oflabiodental

angle

Retrognathic

appeaxance

Decrease

in horizontal labial

angle

Narrowing

of

lips

Increase in columella-philtral angle

2A

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At

the

porcelain-metal

interface

In the metal

29

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30/172

must bc emphasized

that

one

or more of these items are also

frcquently encountered

in

per-

with

intact dentitions

because the compromised

facial support of

the edentulous state is

the

cxclusive

cause

of thc morphological changes.

Patient's weight loss,

age, and hcavy

attrition

manifest orcfacial changes suggestive

ofcompromised, or absent,

dental support

the

overlying

tissues.

guides for

selecting

afiificial teeth from edentulous

patients include:

.

Photographs:

provide

general

information about width and

possibly

outline

fonn.

.

Diagnostic casts:

the form of the teeth can be

very well

judged

from

previous

diagnostic

casts

ofnatural

teeth

,

if

available

(check

with the

patient's prerious

dentist).

.

Intra-oral

radiographs:

the size and

form can be dtermined but

beware because

radi-

ogmphs

can

be distorted and

usually are larger images ofthe

tccth.

.

The teeth of

close

relatives: when no other

means

are

available

to

get

an idea about the

form,

size and shade

of teeth to be used

for thc denture of an edentulous

patient,

records of

son's or daughter's

teeth can

give

a clue.

lt may also help in the arangement

ofteeth as

well

.

Extracted teeth:

sometimes

patients

keep their cxtracted teeth, which

could be

an

excellent

source and aid to delineatc

the form

ofthe

teeth,

thus helping in the selection

process.

1. Degenerative

joint

disease is frequently scen

in denture

wearen but this may be

age related

rather than the state ofthe dentition.

2.

The

recording

of

centric relation

is considered as an essential

starting

point

in

the design ofthe

artificial denture.

3.

ln complete denture

prosthodontics the

position

ofthe

maximum

planned

in-

tercuspation of

teeth or centric occlusion,

is established

to

coincide

with the

pa-

tient's

centric

relation.

of

the

major

reasons

for

the acceptance

ofporcelain

fused to metal

restorations

is

greater

strength

and resistance

to

fracture. The combination

of

porcelain

and

metal,

is stronger

than

porcelain

alone.

Because true adhesion

occurs,

the bond

is

such that

failure or

fracture

will

occur

in the

porcelain

farther

than at the

interface.

points

conceming

the metal-ceramic

crown:

.

The necessary

thickness

ofthe

metal substructue

is

0.5

mm

.

The minimal

porcelain thickness is 1.0-1.5

mm

.

Based on

the

above

points,

the

tooth reduction

necessary

for the metal-ceramtc

crown

is

approximately

1.5-2.0

mm. The labial shoulder

width

is ideally

1.5 mm.

.

The most

frequent

cause

ofporosity

in the

porcelain is inadequate condensation

of

the

porcelain

.

The effectiveness

ofcondensing

porcelain powder to reduce shrinkage

is determined

by the shape

and size

ofthe

particle

Porcelain

is much stronger

under compressive

forces than

it is when sub-

to tensile

forces

by the opposing

teeth. Porcelain fracture

in all-ceratnic

restorations

avoided by

keeping the angles

ofthe

prparation rounded.


31/172

Porosity

Thickness

Surface

area

All

of

the above

30

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201

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Which of

the following are

indications tbr lixed

bridgework

or

important

considerations

to

think

about when

contemplating

the fabrication of lixed

bridgework for

a

patient?

A

limited

number ofedentulous

areas which would not otherwise be more satisfactorily

re-

with

a removable

partial

denture

The need to

prevent

the

over-eruption ofopposing teeth

and the

ddft

of teeth neighboring

edentulous space

The presence

of

suitable abutment teeth

-

favorable

crowr/root ratio, adequate alveolar

absence

ofapical

pathology,

etc.

Esthetics

Patient motivation, including time

availability

Clinical

and technical ability

ll

ofthe above

31

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32/172

used in dentistry to connect bridgework and in fabricating orthodontic ap-

Gold solders are

generally

used

for

fixed

bridgework

and silver solders for or-

appliances. It is important that the solder melt at least 150oF below the fusion

ofthe

metals

or alloys being solders

(for

obvious

reasons).

good

solderjoint

between

2

castings

requires

clean surfaces and

fre electrons pres-

surfaces.

used

dental

solders

include:

The

bonding

ofthe

solder

is

contingent upon

wetting ofthejoined

surfaces by the

and

not

upon

melting

ofthe

metal

components.

is the most important

prerequisite

ofsoldering,

since

the soldering

process

upon wetting

ofthe

surfaces to achieve bonding.

Fluxing

is the oxidative clean-

ofthe area to be soldered. Fluxes are used to dissolve surface

impurities

and

to pro-

the surface from oxidation

while heating. Note: Fluxing is

also

performed on molten

alloys during

the

casting

ofa

crown or

partial

denture

framework.

for

fi

xed bridgework:

.

Poor oral

hygiene

.

High

caries

rate

.

Multiple

spaces

in the

arch

or teeth

likely

to be lost in the near

future

.

Space

not

detrimental

to the maintenance

of

arch

stability

or dental health

.

Unacceptable occlusion

.

Bruxism

l.

If the

clinical

and technical

skills ofthe

dentist

do

not match

the

demands

ofthe

case,

fixed

bridgework

should not be undertaken because

a failed bridge

.

is

likely

to be more detrimental to dental

health than a

failed

removable

partial

dnture.

2.Unless specifrcally

contraindicated,

fixed

restorations are always

the treat-

ment

of

choice.

3.

Fixed bridgework can be used

in

conjunction

with removable

partials.

Ex-

ample: A

patient with

a

couple

ofmissing

anterior teeth and

no

posterior

teeth.

Treatment

could be

fixed

bridgework in

the

anterior

and a

partial

denture re-

placing posterior teeth.

4.

Although

somewhat controversial,

the literature recommends

that

you

should

not splint natural

teeth

and

implants

in

a

fixed

partial

denture.

Implants

have no

periodontal

ligament

and so do

not have the same capacity to ab-

sorb shocks

as do natural teeth

(they

have dffirent

mobilityb). When this

bridge

is

subject

to occlusal loading,

the

difference

has been shown to be

detrimental

to

the

natural

teeth as

well

as cause bone

loss around the im-

Dlants.


33/172

Periodontal

disease

Recunent

caries

Vertical

root fracture

The

need for an apicoectomy

32

Coplrigh

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201 l-2012 - Dental

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All

of

the

following

are

indications

for

porcelain

veneers

EXCEPT

one,

Whieh

one is the

-EXCEPZOfr?

Coverage

of

labial

surface defects

-hypoplasia

of

the enamel

of discolored teeth

-tetracycline

staining,

discoloration

following loss

of

vitality

The

severe

imbrication

ofteeth

Repair

of structural

damage

-

fractured

incisal

edges

Improvement

of

tooth contour

*peg-shaped

lateral incisors

Reduction

of

spacing in cases when orthodontics would

be

inappropriate

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34/172

The

main symptom

will almost always be

pain

when

biting.

The

radiograph

usu-

appears normal.

of

using

a

post

and

core as opposed

to

a

post

crown

when restoring en-

treated teeth:

.

The

marginal adaption

and

fit

ofthe

restoration

is

independent on

the

fit ofthe

post

.

The restoration can be

replaced at

some

time in the future, ifnecessary

without dis-

turbing the

post

and core

.

Ifthe

endodontically

treated tooth

is to serve as a bridge abutment,

it

is not neces-

sary to make the

root canal

preparation parallel

with

the line of

draw

ofother

prepara-

tions

-

it

can be treated as an

independent

abutment

post

and core, when used,

is made

separate

from the

final

restoration.

The crown is

over

the

core

just

as a

restoration

would

be

placed

over

a

done

in tooth structure.

with

little or

no

clinical

crown

that have roots

with

adequate

length, bulk, and

a

post

and core can be utilized.

For posterior teeth

with

less

extensive

de-

ofcoronal

tooth structure, or

for those

possessing

less favorable

root conhgura-

a

pin

retained amalgam

or

composite core can be used.

Other

contraindications

to

porcelain veneers include: traumatic

occlusal contacts, un-

insufficient tooth

structure, and

insumcient enamel.

for Insertion

of

Porcelain Veneers

.

The

veneer should

be

tried in

wet

with

either a drop

of

water or

glycerine to check

for fit. A reliable estimate

for

the

possible post-cementation appearance

with try-in

pastes

can also be

performed.

.

The

veneer

fit

surface

should be cleaned

to rernove any saliva contamination

or

try-

in composite

.

Ifthe

fit

surface

has not

previously

been

treated

with

silane and

protected

with

light-

cured unfilled resin, this should be done

at

this

stage

.

The

enamel surface

should be cleaned

with

pumice

and

water

.

While protecting adjacent teeth with

matrix

strips,

the enamel

is

acid-etched

with

di-

luted hydrofluoric

acid.

Note:

The etched surface

is washed and dried

and a layer

of

unfilled

bond

resin is applied and

thinned

with oil-free

air

.

An

appropriate

shade

oflight-cured

composite is applied

to the

fit

surface

ofthe

ve-

neer

which

is

"puddled"

into

place

on

the

tooth surface

.

Gross excess

of

composite

should be removed and light-curing

completed

.

Remaining excess composite

is removed

with finishing

diamond

burs, discs, strips,

etc., and

the margins

finely

polished

.

The patient should be seen

in

approximately

one week


35/172

One

Two

Thiee

Four

34

Cop,.righl O2011,2012

-

Denral Decks

Maxillary premolar

Mandibular

premolar

Mandibular molar

Maxillary molar

35

Coplright @

201

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12 - Dental Deck


36/172

One factor that

limits th length ofthe

pontic

span

is the abutmnt teeth's

ability to accept

the

ad-

occlusal

load while

providing

adequatc support to the cemented

fixed

partial

denturc.

Ant's law stales

the

root surface

arca ofthe abutment

tcelh supported by bone

must

equal

or surpass

the root surface area

teeth

being

replaced with

pontics.

edentulous spacc

involving four

adjacent teth otherthan four

incisors

is

usually

best

treated lvith a re-

partial

denlure.

[f

more than one edentulous

space exists in the same

arch, even

though each of

be

individually

rcstorcd with a bridge, it

may

be dcsirable

to restore

them with a

removabie

par-

denture. This

is

especially

true ifthe

spaccs

arc bilateral and each one

involves two or

more missing teeth

molars can

rarely be used as abutments,

sinc they fiequently display

incomplete eruption;

shon, fused

and a marked

mesial inclination in the absence

ofa second molar

Note: Diverging

multirooled, curvd,

broad labiolinglal

roots are prefened over fused, single, conical,

and

round circumferential

roots.

.

Splinling adjacent

abumlent

teeth in a fixed bridge

is

primarily

done to improve

the distrit ution ofthe

occlusal load,

.

In order to maintain

and

protect

the

health

ofthe

gingival

tissues and

prcvent

recession,

lhe correct con-

tour

of

the cro$n's

gingival one-third to one-fifth and

interproximal

areas

are

most impofiant

in the final

restoratioD,

.An

anterior fixed bridge

is contraindicated

when there is considerable

resorption

ofthe

rsidual bridge.

A removable

panial

denrure

would be indicated

in this

case.

.

Horizontal

loads

1ol

&,c"t

on natural or abutmcnt

teeth are most deslructive

to the

pcriodontium.

.

Abuimenls with hatfor

lss ofbone support

and loss

ofattachment

have

a

poor prognosis.

.

\\'hen

replacing the

maxillary or

mandibular canine,

the central and lateral

should be splinled

to

prcvent

lateral drifting

oflhe fixed bridge.

.

Aburment teeth must

align to a common

path

of insertion

(/o/

orvious

reasons

when lryng lo seat lhe

hrklge).

.

Short root-to-crown

r^lio

(less

lhan./:21

with conical roots should be

avoided as abutmenls.

.

\atural reeth exert

more force than an

RPD or complete denture when

opposing a fixed

bridge

.

Ideaff)--, rhe supportive

surface area

(peiodontium)

of lhe abutment

teeth should be equal

to but not

leis than ha ofthe

teeth to be replaced

design

preserves the

lingual

surface and

is indicated for restoring

mandibular

mo-

with

damaged buccal

surfaces and intact

lingual

surfaces.

It is also useful

on teeth

with

lingual

inclinations

where large quantities oftooth structure

would be

destroyed if

veneer crown were

to

be

used.

standard

thre-quarter

crown

is a

partial

veneer crown

in which

the buccal sur-

left uncovered.

It is the

most

commonly used

form

ofthe

partial veneer crowns.

patient

with

a

high

caris

index, short clinical

crowns, and

minimal

horizontal over-

would

not be a candidate

for

partial

veneer crowns.

The restoration ofchoice

would

a

full

metal-ceramic

crown,

Rtention and

resistance

forms

in

full

coverage

preparations

on short

molai:s can

enhanced by

placing

several

vertical

grooves

or boxes.


37/172

According

to the

ADA classification

for alloy systems used

for metal-ceramic

restorations.

noble

allovs:

Have

a noble metal content

of

2 600lo

Have


of

> 45%

Have a noble metal content

of

> 25o%

Have


of ) [

50%

36

Copyright

O

201l-2012 -

Dental Decks

Periodontal health

of

the

gingival

tissues is a

major

concern when

phnning

any

fixed

prosthodontic

treatment.

For

optimum

periodontal

health,

restoration linish

lines

should be:

\\'ithin

the sulcus

at

least 1.0 mm

and away

from

the free

gingival margin

without

encroaching on the

biologic width

Terminated at the free

gingival

margin

Supragingival whenever possible (at least

0.5

mm

from

the

free gingival ntargin)

to

allow

for hygienic cleansing

As far as

possible

subgingivally

into the attachment

apparatus

37

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38/172

classification for alloy systcms uscd for metal-ccrumic rcstontions

.

High

noble alloys

(old

tem

was

pre.ious

netal)t >

60o/n

noblc rr'ctal contcnt

(gold

> 40%)

.

Nobfe alloys

(o//

ter"r,

tr^r

senripreciout

metal):

> 2570 noblc mclal contcnt

(

o

gold

rcquircd)

.

Base metaf affoys

foll

term was nonptecious metal):

Documents

Prosthodonticsdd2011-2012.pdf