lecture notes on prosthetics dentistry

8/17/2019 Lecture Notes on Prosthetics Dentistry

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LECTURE NOTES ON PROSTHETICS DENTISTRY(PROSTHODONTICS)

Sumdili 11:52 AM Prosthetic Dentistry

History taking for construction of a partial or complete

denture Patient complain

1. Appearance: Aesthetics

2. Function: to restore function

Previous denture wearer

1. Pain

2. Retching

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2/45

. Pro!lems eating "ith prosthesis

Denture history

1. #e" denture "earer

2. $ld denture "earer

. Age of denture "hen "as %rst "orn

&. 'o" many sets of denture "orn

5. 'aterial of denture

General dental history

1. #um!er of Missing teeth in upper arch

2. Missing teeth in lo"er arch

. $ral hygiene condition

&. Al(eolar !one status

5. )pper and lo"er arches

*. Any areas of !one resroption

+. Periodontal pro!lems and gum recession

,. #um!er of %lled teeth

-. Any cro"ns present

1./ridges

11. $rthodontic therapy 0

12. ndodontically treated tooth

1. Splints

1&. Pre(ious treatment tried for present complaint

Medical history

Any medical condition

Aniety and depression status of patient

'istory of stro3e 0muscle disorders


3/45

Social history

1. Marital status

2. Mo!ility

. Access for treatment

&. Drin3ing

5. Smo3ing

*. 4o!

+. amination

Extraoral examination

1. M4 positioning "hile closing and opening of 6a"

2. Any clic3ing of M4

. Masseter hypertrophy

&. enderness in 6oint or muscle of mastioation

Facial counture

1. $ld photographs

2. 7oss of dental !ulge

. Perioral s3in "rin3ling

&. Angular cheilitis

5. 8ertical hight

*. 7ip seal 0 o(er closure 0 or anterior open!ite

ntra oral examination

1. mucosa

2. erostomia0

. candida mucosal ulceration

&. gingi(al hyperplasia

5. undercuts


4/45

Periodontal health

1. oral hygiene

2. periodontal status

. mo!ility and drifting of remaining teeth

!aries

1. num!er of carious teeth

2. and %lled teeth 0

. recurrent caries

"cclusion

1. s3eletal classi%cation 0

2. competent lips 0

. prognathism 0

&. o(ererypted teeth cro"ding or

5. spacing of teeth

Endodontic status of teeth

8ital and non (ital teeth

ndodontically traeated teeh

Support of edentulous area

1. 9uality of saddle area of al(eolar !one


5/45

2. Degree of !one resorption

. Presence of tori 0 tu!ercle

&. /ony or a!!y ridges or muscle attachment

Denture examination

1. present denture or

2. pre(ious denture eamination

. amine !oth interiorly and

&. etra oral emmination

#hen existing denture in place examine

1. ;s the free"ay space appropriate<

2. ;s the most retruded contact position registered correctly<

. Are the lips supported "ell

&. Are !oth the posterior and anterior occlusal plans in harmony

5. Are the upper and lo"er dentures retenti(e at rest<

*. Are the dentures sta!le in function<

+. ;s there any pain on occlusion<

,. Does the patient li3e the appearance of denture<

-. =an the patient articulate properly "ith the denture

#ith existing denture out of the mouth look for$

1. ;s the !ase etension0 anterior posterior0 lingual and !uccal appropriate

2. ;s the denture )nder etended in lingal pouch and retromolar pads and on

hard palate or


6/45

. ;s the denture o(eretended o(eretended to the eternal o!li>ue ridige

of the mandi!le

s the tooth position appropriate %

!ommon pro&lem includes$

1. ecessi(e lingual positioning of posterior mandi!ular teeth and0

2. ecessi(e la!ial positioning of anterior teeth

)nderetension ? 7o"er Dentures are fre>uently

underetended ;n lingual pouches and retro molar pads

)pper denture ? )nderetended0distally on the hard palate

$(eretension ? 7o"er Dentures are fre>uently

$(eretended to0he eternal o!li>ue ridge of

mandi!le

Has the denture &een altered since the insertion

1. Addition

2. Relining

. Repair

s there any sign of parafunction e'g'

1. cessi(e "earing of denture ? aged denture

2. @ear facets


7/45

. ongue thrust0

&. =lenching of 6a" 0

5. eating on one side only

(adiographic Examination

(adiographic examination of partial denture wearer$

can reveal 0

1. Periodontal !one le(el

2. proimal caries

. Apical pathology

&. Retained roots

5. )nerypted teeth

*. Ridge contour

+. /one height and "idth

,. Anatomical features such as the inferior al(eolar canal

-. Mental foramen 0 maillary sinus M4 anatomy

useful radiographs for prosthodontics are $

1. periapicals

2. panaromics

. occlusal

&. lateral cephalometrics and

5. tomograms

Some cases re)uire special tests and additional features of

prosthodontoc examination


8/45

*hese are$

1. study cast

2. sur(eying

. full occlusal assessment

&. diagnostic "a up

Study cast determine $

;nterarch and intraarch relationship

Re(eal o(ererypted and tilted teeth

'elps plan the design of saddle area

'elpful for construction of primary !ases or tray construction

)sed for "a pattern

'elpful for outlining the diBcult daddle area

Surveying

1. Sur(eying of cast is useful in areas of undercut and

2. determine potential path of insertion 0

. remo(al or displacement of partial denture

&. ;s helpful for design of denture

Full occlusal ad+ustment

1. For determination of lateral 6a" mo(ements

2. May !e re>uired for face !o" mounting of maillary cast and

. he use of semiad6usta!le articulator

&. Particularly useful for tooth "ear and craniomandi!ular disorders

Diagnostic wax up

May !e helpfulC for e(aluation of alternati(e design

=an help patient e(aluation of options


9/45

Partial Dentures design

1. May !e in acrylic or

2. =o!alt chrome denture

,lternative to denture

1. Fi appliance e.g. cro"n !rides or

2. ;mplant $r

. #ot "earing denture at all

Preprosthetic management

1. Any caries

2. ndodontic treatment

. Periodontal trement must !e controlled !efore any prsthodontic construction

-o prosthodontic treatment for cases

1. 7ess moti(ated

2. #o aesthetic pro!lem

. #o functional pro!lem

&. Sta!le occlusion or in harmony

!hanges following extraction of teeth

*here are . types of changes

1. Facial changes

2. ;ntraoral changes

. Psychological changes


10/45

Facial changes following extraction of tooth

1. 7oss of dental !ulge

2. 7oss of lip support

. @itches chin

&. 7ips folds in"ards

5. And loo3 thinner

ntraoral changes following extraction of teeth

1. 7oss of mandi!ulr height ? & mm after one year

2. -1 mm after 25 years

. 7oss of maillary height is ine >uarter of loss of mandi!ular height

&. Decreasded masticatory performance

5. Decreased propiocepti(e a!ility

*. Resorption of !uccal !one "idth

Psychological changes following tooth extraction

1. Some people %nd edentulousness diBcult to accept

2. $r gro"ing old or as a result of underline systemic disease

. $r lac3 of self moti(ation and lac3 of interest

!omplete dentures principles

"The artifcial teeth should replace the denture space( space

previously oocupied by natural teeth ) approximitelt the same

position number shape and size and place"

Features of complete dentures

1. Eood retention


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2. Eood support

. Eood muscle !alance

&. Eood occlusal !alance And

5. sta!ility

!omplete denture (etention

1. Retention is the resistance to displacement of a denture a"ay from the

ridge

2. Eood retention gi(es psychological comfort

. For good Retention close contact !et"een denture and tissue

(etention of lower denture is more di/cult to achieve &ecause of

the$

Mo!ility of mandi!le and oor of mouth than mailla

Support of complete denture

Support is resting of denture on the mucosa and al(eolar !one

E0ective support re)uires

• Denture co(er the maimum surface area "ithout mo(ing or

impinging on soft tissue

• Eood tissues are the tissue resistant to resorption capa!le of ta3ing

load during function

issues most capa!le of resisting (ertical displacement should ma3e contact

"ith !ases during function


12/45

Di0erent areas in complete dentures

1. Primary support area

2. Secondary support area

. Areas non contri!uting to support

&. Areas to !e relie(ed

Primary support area is$

Primary support area in upper denture is hard palate

Secondary support areas in complete dentures is$

al(eolar ridge crest

,reas non 1 contri&uting to support$

Denture !order

,reas to &e relieved in upper complete denture construction

1. Mid line suture and

2. incisi(e papilla

Primary support area in lower denture

1. !uccal shelf and

2. Pear shaped retro molar pad


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Secondary support area in lower denture$

7o"er al(eolar ridge crest and

Eenial tu!ercles

,reas non2 contri&uting to support$

7a!ial ridge incline

(elief area in lower denture$

1. 7ingual ridge incline and

2. mylohyoid ridge

. prominent genial tu!ercle

&. prominent mental tu!ercle

Muscle &alance

1. Muscle !alance is achie(ed "hen the forces of muscles of lips 0 tongue 0

chee3s do not dislodge the denture during functional mo(ements of the

mouth and

2. @hen the teeth are out of contact

. =onca(e shape of denture polished surface gi(es a (ertical seating force

"hen !uccinator contract

&. A thinner denture ange in the premolar region results in more free

mo(ement of the Modiolus the site of muscle %!er decussation from

!uccinator and or!icularis oris muscleG


14/45

Muscles &alance provided &y muscles

1. $r!icularis oris ? lips

2. /uccinator ? chee3

. ongue

&. Modiolous

5. Retromolar pad ? pterygomandi!ular raphae

"cclusal &alance

1. $cclusal !alance is achie(ed "hen the forces of one denture do not dislodge

the other denture during functional 6a" mo(ements "ith the teeth in contact

2. his can !e achie(ed !y a !alanced articulation

Sta&ility

1. ;s the a!ility of dentures to resist displacement !y functional stresses.

2. Sta!ility gi(es physiological comfort

Design features of complete denture

1. Maium etention of denture !ases

2. Peripheral seal

. Postdam

&. Fraena

5. Relief areas


15/45

*. Retruded contact position

+. /alanced articulation

,. Free"ay space

-. ooth position

1.Aesthetics

Denture faults

1. ;ncorrect peripheral etension

2. eeth set not in neutral Hone

. )n !alanced articulation

Polished surface is unsatisfactory

1. Patient factors

2. ;nade>uate sali(a

. Poor ridge forms

&. Decreased adapti(e s3ills

3urning mouth'

Sensiti(ity to acrylic monomer

Speech di/culties

1. DiBcult F0 8 sounds ? incisors are set too far palatally

2. DiBculty "ith S0 0 D sounds ? incorrect palatal contour Icorrect palatal

contour

. S !ecomes JthK incisors set too far palatally or palatal plate too thic3

#histling sound produced

Palate (ault too high !ehind incisors


16/45

!licking teeth

Due to increased occlusal (ertical dimension

(ecurrent fractures of denture'

1. =arelessness

2. #otching of denture

. Fla!!y ridges

&. $cclusal faults

5. Acrylic fatigue due to constant stressing

*. Fleing of denture

!andida and denture

1. )se antifungals

2. #ystatin suspension 10 units Lml or

. Amphotericin suspension 1mg Lml or 2 miconaHol gel

For !omplete denture Maximum extension of denture &ase &y

=o(ering the "hole of the a(aila!le space of denture !earing area

n maxillary upper &ase$

Posterior etension is 6ust anterior to the line of eure of the soft palate

n mandi&ular 4 lower 5 denture &ase$

1. Posteriorly etended to the retromolar pad and

2. lingually to 7ingual sulcus region


17/45

Peripheral seal

1. ;s the of contact !et"een the mo!ile mucosa and the denture surface and 0

2. is determined at the master impression stage

. Eood peripheral seal is good for the retention and sta!ility

Potsdam is$

1. A round smooth line at the 6unction of hard and soft palate

2. Aids in peripheral seal of maillary denture

Fraena$

1. 7a!ial frenum 0

2. !uccal frenum0

. lingual freum and

&. !uccal frenum

5. A techni>ue of impression ta3ing is adopted to o!tain fraenal relief

(elief areas$

1. Small tori

2. Prominent mylohyoid ridge

. prominent mental ner(e foramen $ften ha(e to !e relie(ed


18/45

(etruded contact position

1. =omplete denture should !e registered in the most retruded contact

position

2. his is the position of the mandi!ular condyles in the most retruded position

in the glenoid fossa

. As this is the most reproducia!le position

3alanced articulation

1. he complete denture should ha(e a !alanced articulation

2. @hich is the continuous contact position of upper and lo"er cusps

. all around dental arch during all closed grinding mo(ements of mandi!le

Freeway space

1. 2& mm of free space in (ertical dimension for construction of complete

denture

2. his is the distance !et"een the t"o arches in rest position

. his space is (aria!le in indi(idual mandi!ular mo(ements in speech

Position of 6pper anterior teeth

1. Are set la!ial to the residual ridge

2. hey are 1mm la!ial to the middle of the incisi(e papilla

. A!out 2 mm of teeth are sho"n "hen lips are apart and relaed

7ower anterior teeth

1. ;f there is little ridge resorption 0

2. teeth should !e placed marginally in front of the ridge crest

. ;n cases "here there is lots of ridge resorption


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&. teeth should !e placed to the !uccal sulcus

6pper posterior teeth set up

1. slightly !uccal to the residual ridge

2. and parallel to the alatragus line

7ower posterior teeth set up

eeth should !e set directly o(er the ridge

,esthetics

According to indi(idual needs of patient

@ithout loss of functional concepts

*ypes of impressions

1. Mucocompressi(e and

2. Mucostatic

Mucocompressive impression is$

1. an impression under load

2. so that the mucosa is reduced in (olume e>ually and e(enly condensed

Mucostatic impression is$

1. Made "ithout load application

2. so that mucosa is neither displaced nor compressed


20/45

for insertion of complete denture incorrect occlusal &alance is

checked &y $

1. using articulating paper

2. and modi%ed !y selecti(e grinding

f there is muscle &alance pro&lem $

grinding of denture periphery may !e re>uired

o(eretention should !e corrected

speech chec3ed

and patient allo"ed to comment on denture

!ommon denture pro&lems

1. ;nade>uate support

2. Pain on pressure on supporting areas

. Discomfort under denture

&. /urning sensation in denture !earing areas

5. @ith no redness or ulceration

nade)uate retention 7oose denture

1. At rest and in function

2. Denture can !e remo(ed "ithout any resistance

. Denture is remo(ed from mouth after %rmly seated in mouth

&. is treated !y impro(ing peripheral seal !y self cure acrylic

5. relining the denture may !e re>uired


21/45

Muscle &alance pro&lem

1. dentures !ecomes loose during function and drops

2. denture feel too large

. chee3 !iting

&. on tongue protrusion lo"er denture comes out

5. this is treated !y careful trimming of denture area encroaching on muscles .

"cclusal &alance pro&lem

1. patient "ears denture "ell !ut %nd diBcult to eat "ith it

2. there may !e pain on pressure or

. denture mo(es "hen teeth grind together

&. pro!lem can !e treated !y slecti(e grinding or

5. la!oratory remounting or

*. resetting of teeth

,ppearance pro&lem

1. shade of tooth "rong

2. shape of teeth "rong

. too much or too little tooth sho"s

&. lips loo3 odd

5. face loo3s asymmetrical 0 patient unhappy

*. pro!lem is treated !y resetting of teeth

+. is due to incorrect recording (ertical or horiHontal components of occlusion

Speech pro&lems

1. pro!lem "ith F and 8 sounds or hissing S sounds


22/45

2. may !e due to tooth position

. or (ertical dimension of occlusion

&. notoriously diBcult pro!lem to sol(e

(etching

1. Retching is a protecti(e ree

2. amination and impression ta3ing is diBcult

. here may !e psychiatric elements to retching

&. is treated !y progressi(e adaptation to denture

5. construction of !ase plates %rst

*. hypnotherapy or desensitiHation therapy

,crylic allergy

For pro(en acrylic allergy an alternati(e material may !e considered

,crylic alternatives are

1. 8ulcanite

2. #ylon

. Polycar!onate are useful alternati(e materials

&. porcelain teeth are alternati(e to acrylic teeth

Partial Dentures ,im

1. Partial denture should not damage the ad6acent teeth

2. $r restoration

. Partial denture is designed according to the periodontal health

&. Should restore function and aesthetic


23/45

Pro&lems arising as a result of non replacement of missing teeth $

1. DirNting and tilting of ad6acent teeth

2. $(ereryption of opposing teeth

. Decreased masticatory function

&. craniomandi!ular disorders

5. o(erloadoing of remaining teeth or mucosa

*. tooth "ear

+. poor oral hygiene

,. speech pro!lems

-. aesthetic pro!lems

-egative e0ects of partial dentures

1. increased pla>ue accumulation

2. dental caries

. gingi(itis

&. periodontitis

5. gingi(al stripping

*. o(erloading of a!utment teeth

*hese pro&lems can &e solved &y$

1. careful partial denture design

2. patient selection

. moti(ation

&. oral hygiene instructions

5. regular chec3ups

*. and achie(ed !efore partial denture construction


24/45

Partial denture Design

Systematic approach to partial denture design construction must !e follo"ed

for each case according to the Oennedy classi%cation

Kennedy classifcation o edentulous space

Class I = bilateral ree end saddle

Class II = unilateral ree end saddle

Class III = unilateral bounded saddle

Class I = anterior across the mid line

!addle classifcation(Craddoc#$s classifcation)

%& !addle is part o alveolus rom 'hich teeth are missin

& *ucosa borne + e&& bilateral ree end saddle

,& Tooth borne + e&& small bounded saddle

-& Tooth and mucosa borne

*ypes of connectors in maxilla

1. Anterior palatal !ar used for anterior saddle or for indirect retention in a

!ilateral free end saddle

2. Mid palatal !ar connect 2 posterior !ounded saddle

. Posterior palatal !ar Posterior !order on the (i!rating line used for free end

saddles


25/45


26/45

1. $cclusally approaching clasp

2. Eingi(ally approaching clasp

. ; !ar clasp

(ests provide tooth support common types include$

1. $cclusal rests

2. =ingulum rest

"cclusal rests 1 placed mesially or distallty on

1. occlusal surface of molars or premolars .

2. may re>uire tooth prepration 0

. must not interfere occlusion

!ingulum rests are placed on the

1. cingulum of incisors and canine

2. may re>uire tooth prepration

Prosthotics

1. During fa!rication of lo"er denture it "as slightly etended so "hat muscle

does it touch.

2. @hy is it that you cure slo" o(ernight than rapid cure

3. @hich ner(e supplies the posterior third of the tongue?

#hat is an immediate denture%


27/45

An immediate denture is a complete denture or partial denture inserted on

the same day0immediately follo"ing the remo(al of natural teeth.

#hat are the advantages of an immediate denture%

1. here are se(eral ad(antages of an immediate denture.

2. he most important factor is that the patient "ill ne(er need to appear in

pu!lic "ithout teeth.

. ;t is also easier to duplicate the shape0 color and arrangement of natural

teeth "hile some are still present in mouth.

&. @hen an immediate denture is inserted at the time of etraction0

5. ;t "ill act as a /andAid to protect the tissues and reduce !leeding.

*. An immediate denture "ill allo" esta!lishing speech patterns early. Qou "ill

not ha(e to learn to spea3 "ithout a denture in place and then later relearn

to spea3 "ith a ne" denture.

+. An immediate denture "ill also allo" to che" !etter than "ithout any teeth

and minimiHe facial distortion that may occur "hen teeth are remo(ed.

#hat are the disadvantages of an immediate denture%

1. he !iggest disad(antage is the increased cost.

2. Another disad(antage is that you cannot al"ays see ho" the denture "ill

loo3 !efore the teeth are etracted and the immediate denture is inserted.

. Also0 initially0 an immediate denture does not al"ays %t as accurately as a

con(entional denture0

&. @hich is made after the tissues ha(e healed for si to eight "ee3s follo"ing

etractions0 and "ithout "earing a denture.

#hy does an immediate denture cost more%


28/45

1. An immediate denture is initially more epensi(e than a con(entional

denture !ecause additional time is needed for construction.

2. A surgical stent a guide for recontouring tissues after etractionG is often

necessary and

. more follo"up (isits are needed for ad6ustments and re%tting.

, soft temporary reline material will &e utili8ed for re29tting

denture when it &ecomes loose during the healing process'

1. After the soft tissues ha(e healed and

2. shrin3age of the underlying !one has occurred

. a!out si months follo"ing etractions

*he immediate denture must &e 9nali8ed

1. !y a permanent reline or ne" denture.

2. At this time0 patient "ill !e charged for either a reline or a ne" denture0

depending on choice.

. discuss "ith the patient the pros and cons of a permanent reline (ersus

ma3ing a ne" denture0

, ma+or advantage to making a new denture is$

that the immediate denture can !e a spare denture if the ne" denture

!rea3s0 is misplaced0 or has to !e repaired or relined in our la!oratory.

, ma+or disadvantage to relined$ denture is


29/45

;f the immediate denture is relined0 it "ill usually need to !e left o(ernight

"hile it is permanently relined in the la!oratory.

s an immediate denture for everyone%

1. #ot e(eryone is a candidate for an immediate denture.

2. Some people may !e ad(ised against this treatment0

. due to general health conditions0 or

&. !ecause of speci%c oral pro!lems.

How long does it take to complete%

1. Four to %(e (isits may !e necessary for the fa!rication phase of an

immediate denture0

2. Plus any preliminary surgery.

. For patients re>uiring a complete immediate denture0 the !ac3 teeth are

often etracted si to eight "ee3s prior to the fa!rication phase.

&. his allo"s the etraction sites to heal and a !etter%tting immediate

complete denture to !e fa!ricated.

*he fa&rication phase consists of$

1. impressions0

2. !ite records0

. tooth selection and

&. tryin of the !ac3 teeth.

"n the day of delivery$

1. patient "ill !e seen in oral surgery

2. for etraction of the appropriate teeth0

. follo"ed immediately !y the insertion of the immediate denture.


30/45

Dentures reline helps

1. an old denture %t !etter

2. As "ith age gums and !one underneath the denture changes

. the !one in the mouth "as meant to support natural teeth and

&. "hen these teeth are lost0 the !one resor!s >uic3ly

5. denture acrylic 3eeps its shape and form "hile the gums and !one change

*. so that older denture can get loose and ru! the underlying gums tissues

resulting in ulceration

chairside dentures reline$

1. Erinds a"ay some of the acrylic that contacts the gums.

2. his ma3es room for ne" acrylic "ithout signi%cantly changing the plate.

. #e" acrylic is added to the old and

&. the ne" acrylic !ase is custom %tted to the shape of the gums and !one.

*he self cure acrylic used for relining

is not as hard and dura!le as the processed acrylic used to ma3e the heat

cure acrylic

advantage of chairside procedure is$

1. its >uic3 and

2. patients dont ha(e to "ait a day or t"o to get their plates !ac3.,lginate mpression Materials

1. =ontainer of po"der should !e sha3en !efore use to get an e(en distri!ution

of constituents.

2. Po"der and "ater should !e measured to manufactures instructions.

. @ater at room temperature should !e used0

• this gives a reasona&le working time of $a couple of minutes.


31/45

• Faster or slower setting times can &e achieved 0!y using "arm or

cold "ater respecti(ely.

• *he material nearer the tissues$ sets %rst .

(etention is needed to the impression tray and is provided &y

perforations in the tray andLor adhesi(es.

"nce removed from the mouth the impression should &e$

1. Rinsed "ith cold "ater to remo(e any sali(a or !lood.

2. ;t should then !e co(ered in a damp gauHeLnap3in to pre(ent syneresis

. not placed in "ater "hich "ould cause im!i!itionepansionG.

&. he impression should !e soa3ed in hypochlorite for * seconds and then

cast as soon as possi!le.

Properties of ,lginates

C./*I!T01

1. $n miing the po"der "ith "ater a sol is formed0

2. a chemical reaction ta3es place and

. a gel is formed.

*he powder contains

1. Alginate salt e.g. sodium alginateG

2. =alcium salt e.g. calcium sulphateG

. risodium phosphate

*he setting reaction is as follows:$n miing the po"der "ith the "ater

S"D6M ,7G-,*E S"D6M S67PH,*E

; ;

!,7!6M S67PH,*E !,7!6M ,7G-,*E


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*he chemical reaction occurs too )uickly

often during miing or loading of the impression tray.

t can &e slowed down &y0

1. adding trisodium phosphate to the po"der.

2. his reacts "ith the calcium sulphate

. to produce calcium phosphate0

&. pre(enting the calcium sulphate reacting "ith the sodium alginate to form a

gel.

*his second reaction occurs in preference to the 9rst reaction

1. until the trisodium phosphate is used up0

2. then the alginate "ill set as a gel.

here is a "ellde%ned "or3ing time during "hich there is no (iscosity

change.

2032/0TI/! o alinate

• Eood surface detail

• Reaction is faster at higher temperatures

• lastic enough to !e dra"n o(er the undercuts0 !ut tears o(er the deep

undercuts

• #ot dimensionally sta!le on storing due to e(aporation

• #on toic and non irritant• Setting time can depend on techni>ue

• Alginate po"der is unsta!le on storage in presence of moisture or in

"arm temperatures

4546T47/!


33/45

1. #on toic and non irritant

2. Eood surface detail

. ase of use and mi

&. =heap and good shelf life

5. Setting time can !e controlled "ith temperature of "ater used

5I!4546T47/!

1. Poor dimensional sta!ility

2. ;ncompati!ility "ith some dental stones

. Setting time (ery dependent on operator handling

&. Messy to "or3 "ith

Denture maintenance

ll29tting denture results in

1. Resorption of ridges

2. =andida infection

. denture irritation hyperplasia

&. ;nammatory papillary hyperplasia of palate

(e&asing is$

1. Replacement of all of denture !ase

2. @hen impro(ement in the %tting surface is re>uired

. 'eat cure acrylic is the material of choices

(elining is$

Replacement of %tting surface "ith a self cure acrylic


34/45

7a&oratory dentures relining is a similar procedure'

1. ;nstead of using self cure acrylic0

2.he old denture is used to ta3e a precise impression of the underlying tissues

"ith (ery accurate impression material.

*he old denture is sent to a dentures la& and new acrylic

1. is processed to the old denture in the same manner that the original

denture "as manufactured.

2. he result is a (ery nice "ell %tting old denture.

A dentures relining

1. can help ma3e "earing dentures much more comforta!le 0

2. !ut they should al"ays !e replaced e(ery %(e years

. to ad6ust to the natural changes of face and

&. the changes in the !one "ithin mouth.

mmediate denture de9nition$

denture pro(ided to the patient soon after etraction of a tooth


35/45

,dvantages of immediate denture for patient

1. immediate replacement of etracted tooth

2. no aesthetic loss0

Disadvantages of immediate denture

1. denture !ecomes loose "ith time

2. due to !one resorption and

. tissue regression0

&. cost of ne" denture due to repeat denture

!opy denture is

1. @hen old denture is used to ma3e ne" denture.

2. de%nition: patientKs old denture is used as a model to ma3e ne" denture.

ndications of copy denture=

1. "hen patient is satis%ed "ith the old denture 0 or

2. not "illing to pass through any of the steps of denture ma3ing

. e.g. impression ta3ing or trial

!ontraindications of copy denture


36/45

1. @hen denture is loose or

2. has a ma6or defect0 or

. there is change in the oral structures

&. e.g etraction of a tooth or !oone resorption

Disadvantages of copy denture

Any fault present in the old denture is li3ely to !e repeated.

Maxillary tu&erosity and tooth fracture management%

Allo" the fracture to heal !y pro(iding a supporti(e appliance e.g a denture

or splint

!entric "cclusion

1. the maimal intercuspation of the teeth.

2. he relationship of the mandi!le to the mailla

. "hen the teeth are in maimum occlusal contact0

&. irrespecti(e of the position or alignment of the condyledis3 assem!lies.

5. he occlusion of opposing teeth "hen the mandi!le is in centric relation.

!entric (elation ? retruded contact position

1. he position of the mandi!le

2. "hen the condyles are in an orthopedically sta!le position.

*his occurs when the condyles are in their most superoanterior

position$

1. Resting on the posterior slopes of the articular eminences "ith the dis3s

properly interposed.

2. he maillomandi!ular relationship


37/45

. in "hich the condyles articulate "ith the thinnest a(ascular portion of their

respecti(e dis3s

&. @ith the comple in the anteriorsuperior position against the slopes of the

articular eminences.

5. his position is independent of tooth contact.

*. syn. retruded contact position

!ompensating !urve

1. he anteroposterior cur(ature in the median planeG and the mediolateral

cur(ature in the frontal planeG

2. in the alignment of the occluding surfaces and incisal edges of arti%cial

teeth

. that are used to de(elop !alanced occlusion.

!ross23ite> reverse articulation

1. @hen the maillary teeth occlude "ith !uccal cusps contact the central

fossa of the mandi!ular teeth.

2. An occlusal relationship in "hich the mandi!ular teeth are located facial to

the opposing maillary teethC

. the maillary !uccal cusps are positioned in the central fossae of the

mandi!ular teeth.

syn. reverse articulation

!urve of Monson

archaic sees Compensating Curve

http://www.ada.org/prof/ed/testing/natboard/glossary.asp#compensatingcurve%23compensatingcurvehttp://www.ada.org/prof/ed/testing/natboard/glossary.asp#compensatingcurve%23compensatingcurve


38/45

Functional "cclusion

is the contacts of the maillary and mandi!ular teeth during mastication and

deglutition.

Most common Denture pro&lems

Most common denture pro&lem is$

1. Pain on insertion or

2. loose denture

!an &e due to $

1. Denture errors or

2. Patient factors

Patient fctors are $

1. patient should !e "arned in ad(ance the limitations of a denture

2. ecessi(e sali(ation

. speech pro!lems pain

&. !ruism

5. other paranormal ha!its 0 li3e clenchinh of teeth

!auses of pain$

1. Rough %tting surface

2. rrors in occlusion

. !ruism

&. Retained root

5. Sharp al(eolar ridge


39/45

*. Premature contact

+. cessi(e !one resorption mental foramen pressure or eposure in

localised area of pain

,. 7e(erage due to unsta!le denture

-. =lasp arm too high

!omplain of loose denture is more in$

7o"er denture,ltered !ast *echni)ue

1. ;n Free end saddles dentures 0

2. here is displacement of denture under occlusal pressure

. here is anteroposterior roc3ing around the a!utment tooth0 "hich acts as a

pi(ot.

&. his is as a result of the displacea!ility of the mucosa.

*he altered cast techni)ue is employed

1. to try and pre(ent this anteroposterior roc3ing around the a!utment tooth0

2. !y ta3ing an impression of the mucosa under controlled pressure.

. he metal frame"or3 is constructed on a cast produced !y a mucostatic

impression material0 usually alginate.

&. /aseplates are then constructed in selfcured acrylics on the frame"or3 in

the saddle areas0 these are close %tting.

5. ;mpression paste or a medium (iscosity silicone paste is then applied to the

%tting surface of the selfcured acrylic.

*. he denture is then inserted in place0 held in place !y the frame"or3 only0

+. no %nger pressure is applied as this "ould lead to o(er displacement of the

mucosa.

,. /order moulding is then carried out as the is impression material is setting.


40/45

1. ;n the la!oratory0 the free end saddle areas on the master cast are sectioned

oN.

2. he denture is then positioned on the model and the ne" saddle areas are

poured.

. he resulting model represents the free end saddle areas under conditions0

"hich mimic functional load.

&. Denture construction then continues as normal.

5. he distri!ution of loading of the free end saddles is impro(ed and denture is

more sta!le.

How long do leave the impression in the mouth &efore it?s fully

set%

1. Setting time in the mouth is !ased on use of room temperature "ater.

2. All materials "ill gel in 5 minutes ecept one.

. 7a(ender Acculoid re>uires + minutes to gel.

How do disinfect my hydrocolloid impressions%

'ydrocolloid impressions may !e disinfected !y immersion in one of the

follo"ing:

1. Sodium 'ypochlorite0

2. ;odophor0

. Acid Eluteraldehyde.

Sterili8ation Pouches

SteriliHation Pouches oNer not only the highest >uality dental pouch0 !ut also

features the patented ;nternalProcessing;ndicator. A(aila!le in 12 siHes


41/45

Fixed and (emova&le Prostheses

,ny 9xed or remova&le prosthesis which has &een in the patient?s

mouth 0

1. must !e rinsed under running "ater to remo(e ecess !lood and sali(a.

2. Do not splash "ater ecessi(elyC

. droplet spatter can carry microorganisms.

For !leaning Dentures Place the prosthesis in$

1. an ultrasonic cleaner

2. "ith Mid"est Stain and artar Remo(er

. for the manufacturerKs recommended time.

&. his is the precleaning step of the disinfection procedure.

Prior to ad+ustment or transport to the la&oratory$ disinfect the

prosthesis as follows:

1. Rinse "ith "ater and spray "ith a comple phenol disinfectant.

2. Place in a plastic !ag for 1 minutes0 and

. Rinse "ith "ater.

&. @rap prosthesis in plastic or place in a plastic !agG and send to the

la!oratory.

5. Do not add disinfectant to the !ag.!leaning Dentures

1. )se Mid"estKs Stain and artar Remo(er and follo" manufacturers

directions for proper dilution.

2. @ith glo(es and safety glasses on0 pour Stain and artar Remo(er solution

directly into !ag containing dentures.

. =lose !ag and place in a glass cylinder.&. Fill cylinder "ith "ater.

5. Place cylinder in ultrasonic cleaner and (i!rate for manufacturerKs

recommended time.

*. @earing clean glo(es0

+. remo(e dentures from !ag and thoroughly rinse "ith "ater.


42/45

,. Place dentures in denture cup containing mouth"ash.

-. Remo(e and discard glo(es and "ash hands.

1. Return denture cup to the student or faculty mem!er.Disinfecting mpressions= ,lginate or polyether:

1. Rinse "ith "ater and2. spray "ith a comple phenol disinfectant.. Place the impression in a plastic !ag for 1 minutes0&. rinse "ith "ater0 and pour.5. Pour alginate impressions immediatelyC@' pour polyether impressions immediately or "ithin 2& hours'

Polysul9de$ silicone$ and polyvinylsiloxane:

1. Rinse "ith "ater and

2. immerse in a comple phenol disinfectant for 1 minutes.

. Remo(e and rinse again "ith "ater.

Pour polysul9de and silicone impressions$"ithin 15* minutesC

Pour polyvinylsiloxane impressions 0 "ithin 15 minutes to se(en days.!leaningADisinfecting Prosthodontic tems

1. ;tems contaminated only !y handling or

2. that ha(e minimal contact "ith oral uids

. do not re>uire steriliHation for routine reuse0

&. !ut should !e cleaned and disinfected "ith an PAregistered disinfectant.

Such items include0

1. torches0

2. face !o"s not including the face!o" for3G0

. articulators0

&. rulers0

5. miing spatulas0

*. 3ni(es0

+. ru!!er !o"ls0

,. shade guides0 and

-. mold guides.


43/45

,ny items such as impression trays and face&ow forks that are

placed in the mouth$

Should !e heatsteriliHed.!ontaminated Stone !asts

!ontaminated stone casts transferred to or from a la&oratory area

or a clinic

1. should !e sprayed "ith a comple phenol disinfectant and

2. allo"ed to set for 1 minutes !efore rinsing thoroughly "ith "ater.

. A protecti(e mas3 must !e "orn "hen using a model trimmer."ther #ork2(elated tems

1. All other "or3related items articulators0 case pans0 etc.G

2. "hich are transferred from a clinic to a la!oratory area or (ice (ersa

. must !e disinfected.&. Mo(ing parts of the articulator should not !e disinfected since this may

impair function.

*he following items should &e cleaned and heat2sterili8ed or

chemically disinfected as indicated:

S*,-7ESS S*EE7 !("#-S indications

1. recommended on primary molars

2. Erossly carious molars

. tooth has recei(ed a pulpotomy

&. pro(ide more dura!le and relia!le restoration.

,void:Stic3y foods li3e caramel0 gum0 taNy

'ard candy

=he"ing on ice

Popcorn 3ernels or Told maids


44/45

*he crown of the tooth is protected

1. @here the cro"n meet the gum tissue is an area "here !acteria can li(e

and cause decay.2. ;t is important that parents super(ise the cleaning of this area.

. Ma3e sure child !rushes not only his teeth !ut "here their teeth meet the

gum tissue.

&. ;t is also important to oss0 especially in this area0 once a day.

5. /rush teeth and not ossing is lea(ing & our mouth loaded "ith acid

protecting !acteriaU

*. he cro"ned tooth "ill usually fall out normally "hen the permanent tooth

comes in.

3("BE- DE-*6(E$ 3(DGE$ "( P7,*E

1. Sa(e all the parts of !ro3en denture0 !ridge or partial denture

2. Repair or replace as soon as possi!le

. emporary !ridges0 plates and dentures until the permanent one is repairedor replaced

"(*H"D"-*! P("37EMS 23races

• ;f a "ire is causing an irritation0 co(er the end of the "ire "ith some

!ees "a or a piece of gauHe

• ;f a "ire !ecomes em!edded in the gum or chee3 D$ #$ remo(e it0

go to the dentist immediately

!("#- !"MES "FF

1. ry to snap it !ac3 in

2. Purchase a small tu!e of denture adhesi(e paste put a small amount in the

cro"n and place it !ac3 on your tooth


45/45

. ry Dent emp or empenol as a temporary adhesi(e

&. Do #$ use ordinary household glue

5. =all the dentist as soon as possi!le to recement it properly

uest that the dentures !e "orn 2& hours !efore there(ie" appointment0

*. in order that the cause of the discomfort may !e more readilydetected.

,n ,rticulator1. An articulator assists in the fa!rication of remo(a!le appliances denturesG0

2. is a mechanical de(ice used to casts of the maillary and mandi!ular teeth

are %ed and

. reproduces recorded positions of the mandi!le in relation to the mailla.

&. %ed prosthodontic restorations cro"ns0 !ridges0 inlays and onlaysGand

orthodontic appliances.Plane line articulator

1. he simplest type of articulator consisting of a simple hinge 6oint.

2. #o lateral or sliding mo(ements are possi!le "ith a plane line articulator.

. An articulator that allo"s that reproduces mo(ement of the mandi!le only in

a sagittal plane

lecture notes on prosthetics dentistry

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