SETTING UP THE TEETHSETTING UP THE TEETH

Aims of SettingAims of SettingPreservation of the Preservation of the alveolar bonealveolar boneEstheticsEstheticsMasticatory efficiencyMasticatory efficiencyRetention and Retention and stability during stability during functionfunctionHealth & comfort of Health & comfort of the TMJthe TMJ

Guidelines for Centric OcclusionGuidelines for Centric Occlusionthe upper teeth should the upper teeth should overlap the lower teethoverlap the lower teeththe long axis of each the long axis of each upper tooth should be upper tooth should be distal to the long axis of distal to the long axis of the corresponding the corresponding lower toothlower tootheach tooth except the each tooth except the lower central incisors lower central incisors and the upper last and the upper last molars should be molars should be opposed by two teethopposed by two teeth

Guides to Positioning of Anterior Teeth

Payne stated, “Set the teeth where they grew”Payne stated, “Set the teeth where they grew”Anteroposterior PositionAnteroposterior Position– Distance from papilla, relation to residual ridge, fullness Distance from papilla, relation to residual ridge, fullness

of the lips (lip support), phonetics F & Vof the lips (lip support), phonetics F & VSuperoinferior PositionSuperoinferior Position– Show of teeth, modiolus (lower canine & premolar)Show of teeth, modiolus (lower canine & premolar)Mediolateral PositionMediolateral Position– Midline, ala of the noseMidline, ala of the noseInclination or Slant Inclination or Slant – Labial plate & facial profileLabial plate & facial profile

Guides to Positioning of Guides to Positioning of Posterior TeethPosterior Teeth

Both upper & lower posterior teeth are centered over the Both upper & lower posterior teeth are centered over the crest of the ridge whenever possible to improve crest of the ridge whenever possible to improve balancebalance and and stabilitystability of the denture of the dentureAnterior limitAnterior limit (distal of canine)(distal of canine)

Posterior limitPosterior limit (maxillary tuberosity, retromolar pad)(maxillary tuberosity, retromolar pad)

Buccal limitBuccal limit (crest of the ridge)(crest of the ridge)

Lingual limitLingual limit (mylohyoid ridge)(mylohyoid ridge)

Occlusal limitOcclusal limit (corners of the mouth, ½ - 2/3 of retromolar (corners of the mouth, ½ - 2/3 of retromolar pad, equator of the tongue)pad, equator of the tongue)

Slant or Inclination of the occlusal planeSlant or Inclination of the occlusal plane (curve (curve upward posteriorly, lower have lingual tilt, upper have buccal tilt)upward posteriorly, lower have lingual tilt, upper have buccal tilt)

Anterior Teeth InclinationsAnterior Teeth Inclinations

Posterior Teeth InclinationsPosterior Teeth Inclinations

Features of a Class I RelationshipFeatures of a Class I Relationship

Overjet (2-4mm)Overjet (2-4mm)Overbite (1mm, excessive Overbite (1mm, excessive overbite avoided)overbite avoided)Canine Relation (mesial slope Canine Relation (mesial slope of upper opposes distal slope of upper opposes distal slope of lower)of lower)First Molar Relation (MB cusp First Molar Relation (MB cusp of upper opposes buccal of upper opposes buccal groove of lower)groove of lower)Functional & Non-functional Functional & Non-functional Cusps Relation (cusps to Cusps Relation (cusps to fossae relationship)fossae relationship)

Features of a Class II Features of a Class II RelationshipRelationship

Pronounced overjetPronounced overjetLower canine more posterior and lingualLower canine more posterior and lingualLower premolar maybe ground mesiodistally or Lower premolar maybe ground mesiodistally or removedremovedNonanatomic teeth or teeth with shallow inclines Nonanatomic teeth or teeth with shallow inclines are selected to reduce stresses on the lowerare selected to reduce stresses on the lowerBuccal cusps of premolars are flattened to Buccal cusps of premolars are flattened to stabilized centric occlusionstabilized centric occlusionMolars maintained cusps to fossae relation Molars maintained cusps to fossae relation

Features of a Class III Features of a Class III RelationshipRelationship

Overjet overbite eliminatedOverjet overbite eliminatedIncisors can be set edge to edgeIncisors can be set edge to edgeUpper anteriors set are far forward for lip support Upper anteriors set are far forward for lip support and esthetics; lowers as far lingual without and esthetics; lowers as far lingual without tongue interferencetongue interferenceUpper premolar maybe removed or add lower Upper premolar maybe removed or add lower teeth (premolar or molar)teeth (premolar or molar)Molars maybe set in crossbiteMolars maybe set in crossbiteBuccallingual inclines & transverse ridges of Buccallingual inclines & transverse ridges of posteriors are flattened posteriors are flattened

Cross-Over PointCross-Over Pointthe point at which the teeth the point at which the teeth change from one relationship to change from one relationship to anotheranothere.g. In a class 1 relationship e.g. In a class 1 relationship with a posterior cross bitewith a posterior cross bitethe crossover point could be at the crossover point could be at the 2nd premolarthe 2nd premolarteeth may be set in an end-on teeth may be set in an end-on or cusp to cusp relationor cusp to cusp relation

Trial Wax DentureTrial Wax Denture

WAXING WAXING and and

FESTOONINGFESTOONING

Role of the Polished SurfaceRole of the Polished SurfaceEsthetics Esthetics – – imitate the form of the tissues around the teethimitate the form of the tissues around the teethRetentionRetention – – form of denture base be shaped according the form of denture base be shaped according the muscles and tissues ( lips, cheeks, tongue)muscles and tissues ( lips, cheeks, tongue)Phonetics Phonetics – – contour comparable to that of the palatecontour comparable to that of the palateessential for patient comfort and hygiene of the essential for patient comfort and hygiene of the denturedenture

WaxingWaxingdefined as the defined as the contouring of the wax contouring of the wax base of a trial denture base of a trial denture into the desired forminto the desired formMethods of Adding Methods of Adding WaxWaxA. press on method A. press on method B. drip on method B. drip on method

FestooningFestooningthe procedure of the procedure of carving the denture carving the denture base to simulate the base to simulate the contour of the natural contour of the natural tissues which are tissues which are being replaced by the being replaced by the denturedenture

Procedures in Procedures in FestooningFestooning

1. Cervical cut1. Cervical cutcut wax back to the cut wax back to the cervical line on the cervical line on the artificial teeth, or a artificial teeth, or a little beyond to little beyond to simulate gingival simulate gingival recessionrecessionsharp instrument is sharp instrument is held at a 45 degrees held at a 45 degrees angle to the tooth angle to the tooth surfacesurface

2. Placement of triangular markings2. Placement of triangular markings

* guide to the length and position * guide to the length and position of the root Indicationsof the root Indications

* Maxillary denture* Maxillary denture Canine – longest Canine – longest Lateral incisors – shortestLateral incisors – shortest centrals incisors – in betweencentrals incisors – in between

* Mandibular denture* Mandibular denture Canine – longest Canine – longest Central incisors –shortestCentral incisors –shortest Lateral incisors – in betweenLateral incisors – in between

3. Root indications3. Root indications

wax is scraped out wax is scraped out of the triangular of the triangular markings, to which markings, to which the root indications the root indications will manifest will manifest

MAXILLARY BASE CONTOURMAXILLARY BASE CONTOURGingival MarginsGingival MarginsGingival BulgeGingival BulgeInterdental PapillaInterdental PapillaGingival GrooveGingival GroovePeripheral RollPeripheral RollRoot ProminencesRoot ProminencesCanine FossaCanine FossaBuccal FlangeBuccal FlangeRugaeRugaeStipplingStippling

Palatal SurfacePalatal SurfaceIt has a uniform thickness It has a uniform thickness of 2.5mmof 2.5mmExcess bulk can interfere Excess bulk can interfere with tongue function and with tongue function and speechspeechMidline fracture can occur Midline fracture can occur if the midline area is too if the midline area is too thinthinPalatal slope is Palatal slope is continuous with the continuous with the palatal surface of the palatal surface of the teethteeth

MANDIBULAR BASE MANDIBULAR BASE CONTOURCONTOUR

The gingival features are similar to that of the maxillaBuccal Flanges is Buccal Flanges is made slightly concavemade slightly concaveLingual Flange is Lingual Flange is made slightly concavemade slightly concave

Lingual FestooningLingual Festooning

It restores part of the It restores part of the lingual surface of the lingual surface of the tooth that is not tooth that is not supplied in the supplied in the artificial teethartificial teethIt reduces anterior It reduces anterior palatal bulkpalatal bulkIt improves phoneticsIt improves phoneticsIt gives this region a It gives this region a natural feelnatural feel

Errors in Waxing & FestooningErrors in Waxing & Festooningmake the interdental papilla nonexistent or too smallmake the interdental papilla nonexistent or too small – – provide space for food impaction and provide space for food impaction and makes denture difficult to polishmakes denture difficult to polishplace grooves on the denture base between each toothplace grooves on the denture base between each toothExcessive heatingExcessive heating- can cause movement of teeth & loss of carved detail- can cause movement of teeth & loss of carved detailOverwaxingOverwaxing- can cause excessive trimming of processed denture, - can cause excessive trimming of processed denture, causing warpagecausing warpageUnderwaxingUnderwaxing- can cause dimensional change during curing- can cause dimensional change during curing- leaves inadequate material for finishing & polishing- leaves inadequate material for finishing & polishing- make denture weak and prone to fracture- make denture weak and prone to fracture

TRIAL TRIAL FITTINGFITTINGTRIAL TRIAL

INSERTIONINSERTION

Significance of the Significance of the Trial DentureTrial Denture

Psychological benefitPsychological benefitEvaluation of retention, stability and supportEvaluation of retention, stability and supportEvaluation and verification of centric relation & Evaluation and verification of centric relation & occlusionocclusionEvaluation and verification of facial estheticsEvaluation and verification of facial estheticsEvaluation and verification of teeth arrangement Evaluation and verification of teeth arrangement and estheticsand estheticsEvaluation and verification of denture base Evaluation and verification of denture base contourcontourTo complete the posterior palatal sealTo complete the posterior palatal seal

Trial Fitting Trial Fitting ProceduresProcedures

1. Outside the 1. Outside the mouth - wax mouth - wax denture should denture should be correctly be correctly contoured and contoured and extended into the extended into the sulcisulci

2. Singly in the mouth 2. Singly in the mouth - there should be - there should be

correct extension of correct extension of the bases and stability the bases and stability should be satisfactoryshould be satisfactory

3. Together in the mouth 3. Together in the mouth - check the following:- check the following:

a. Vertical dimension a. Vertical dimension (check freeway space, (check freeway space, phonetics)phonetics)b. Occlusion (maximum b. Occlusion (maximum intercuspationintercuspationc. Esthetics (correct lip c. Esthetics (correct lip support, proper amount support, proper amount of show)of show)

4. Patient’s opinion 4. Patient’s opinion - the patient is asked to look at the - the patient is asked to look at the teeth in a hand mirror and asked teeth in a hand mirror and asked for commentsfor comments- any necessary alterations may be - any necessary alterations may be carried outcarried out- a further appointment for a retry - a further appointment for a retry may be requiredmay be required

5. Phonetics Test5. Phonetics Test

Bilabials (B,P,M) – difficulty indicates Bilabials (B,P,M) – difficulty indicates increase vertical dimesionincrease vertical dimesionLabiodentals (F,V) – difficulty indicates Labiodentals (F,V) – difficulty indicates incorrect incisors position & level of occlusal incorrect incisors position & level of occlusal planeplaneLinguopalatals (J,Ch,Sh) – difficulty indicates Linguopalatals (J,Ch,Sh) – difficulty indicates thickness of palatal surface & incorrect width thickness of palatal surface & incorrect width of dental archof dental archVelar Sound (K,G, NG) – difficulty indicates Velar Sound (K,G, NG) – difficulty indicates thick posterior palatal borderthick posterior palatal border

Common ErrorsCommon Errors

DENTURE PROCESSINGDENTURE PROCESSING

The procedure that involves replacing The procedure that involves replacing the trial base and the waxed portion the trial base and the waxed portion

with the final denture material.with the final denture material.

Denture Base MaterialsDenture Base Materials

Heat cured acrylic resinHeat cured acrylic resinAutopolymerizing resinAutopolymerizing resinLight cured resinLight cured resinPolystyrene and vinyl resinPolystyrene and vinyl resinType IV gold alloysType IV gold alloysBase metal alloysBase metal alloys

Methods of Packing Acrylic ResinMethods of Packing Acrylic Resin

Split-flask loadingSplit-flask loadingInjection loadingInjection loading

PROCEDURES IN PROCEDURES IN DENTURE PROCESSINGDENTURE PROCESSING

(SPLIT FLASK METHOD)(SPLIT FLASK METHOD)

1. Sealing the cast1. Sealing the cast

Once waxing and Once waxing and festooning is complete, festooning is complete, the denture is sealed to the denture is sealed to the cast at its border with the cast at its border with molten waxmolten waxPurposes:Purposes:– This prevents plaster from This prevents plaster from

getting under the denturegetting under the denture– Also, maintains the position Also, maintains the position

of the denture on the castof the denture on the cast

2. Separating the Cast2. Separating the Cast

Cast is separated from the plaster mounting on Cast is separated from the plaster mounting on the articulator by sharp taps of a mallet or a knife the articulator by sharp taps of a mallet or a knife placed at its junctionplaced at its junctionPurposePurpose– For laboratory For laboratory remountingremounting

3. Flasking or Investing3. Flasking or Investing

the process by which the trial denture is the process by which the trial denture is surrounded in stone or plaster in a metal surrounded in stone or plaster in a metal flaskflaskTechniques: 3 pour, 4 pour, 2 pourTechniques: 3 pour, 4 pour, 2 pourPurposePurpose– to create a mold which forms the acrylic into to create a mold which forms the acrylic into

the shape of the final denturethe shape of the final denture

4. Wax Elimination (Dewaxing)4. Wax Elimination (Dewaxing)

Secured flask placed in boiling water for 5 Secured flask placed in boiling water for 5 to 10 minutesto 10 minutesWax and temporary denture base are Wax and temporary denture base are discardeddiscardedMold is flash with clean boiling water Mold is flash with clean boiling water (detergent maybe added)(detergent maybe added)Purpose:Purpose:– to create a mold spaceto create a mold space

5. Trial Packing Of Acrylic Resin5. Trial Packing Of Acrylic ResinSeparating media applied to stone surfaces of the moldSeparating media applied to stone surfaces of the moldAcrylic resin is mixed and container covered to prevent Acrylic resin is mixed and container covered to prevent monomer evaporation until the dough stage, 3:1 by volume monomer evaporation until the dough stage, 3:1 by volume or 2:1 by weightor 2:1 by weightAcrylic dough is formed into a roll and adapted into the mold Acrylic dough is formed into a roll and adapted into the mold spacespacePlastic separating sheet place over the dough and the Plastic separating sheet place over the dough and the halves of the flask and close slowly with pressurehalves of the flask and close slowly with pressureFlask separated, plastic sheet removed & excess acrylic Flask separated, plastic sheet removed & excess acrylic (flash) trimmed off with a blunt instrument(flash) trimmed off with a blunt instrumentRepeat until no flash is formedRepeat until no flash is formedIn final closure, plastic sheet is removedIn final closure, plastic sheet is removedPurpose:Purpose:– Acrylic dough is formed and adapted to the mold spaceAcrylic dough is formed and adapted to the mold space

6. Bench Curing 6. Bench Curing

Secured flask with acrylic placed aside for Secured flask with acrylic placed aside for 30 minutes30 minutesPurposes Purposes – Permits equalization of pressure throughout Permits equalization of pressure throughout

the moldthe mold– For a more uniform dispersion of monomer For a more uniform dispersion of monomer

throughout the mass of doughthroughout the mass of dough– Produces a better bond with plastic teethProduces a better bond with plastic teeth

7. Curing7. CuringAcrylic resin is cured through the process call Acrylic resin is cured through the process call polymerizationpolymerizationPurpose: uncured acrylic converted to its final; Purpose: uncured acrylic converted to its final; usable formusable form2 methods 2 methods – Short curing cycleShort curing cycle

Flask kept in water at room temp & temp is raised to 74Flask kept in water at room temp & temp is raised to 74ooC C (165(165ooF) for 2 hours and boil for 1 hourF) for 2 hours and boil for 1 hour

– Long curing cycleLong curing cycleWater temp is maintained at 74Water temp is maintained at 74ooC for 8 hoursC for 8 hoursLess risk of porosityLess risk of porosityLess residual monomer contentLess residual monomer contentIndicated for thick acrylic applianceIndicated for thick acrylic appliance

8. Cooling8. Cooling

Flask is removed from the curing chamber and Flask is removed from the curing chamber and allowed to cool (bench cooling)allowed to cool (bench cooling)– Slow CoolingSlow Cooling

Flask is opened only after it has cooled sufficiently, some Flask is opened only after it has cooled sufficiently, some laboratories leave it cool overnight in the water in which it was laboratories leave it cool overnight in the water in which it was processedprocessed

– Faster CoolingFaster CoolingAllow flask to bench cool for 30 minutes then place it under Allow flask to bench cool for 30 minutes then place it under running tap water for 30 minutesrunning tap water for 30 minutes

Purpose: prevent distortionPurpose: prevent distortion

9. Deflasking9. Deflasking

The denture is retrieve from the flaskThe denture is retrieve from the flask2 halves of flask are separated by inserting a 2 halves of flask are separated by inserting a strong wedge between the halvesstrong wedge between the halvesThis permits the stone mold to be retrieved intactThis permits the stone mold to be retrieved intactThe 3 pour technique facilitates easy separation The 3 pour technique facilitates easy separation of the 3 layersof the 3 layersCare should be taken to prevent the separation Care should be taken to prevent the separation of the denture from the castof the denture from the cast

10. Remounting & Selective 10. Remounting & Selective GrindingGrinding

The casts are repositioned back on their The casts are repositioned back on their plaster mounts in the articulator using the plaster mounts in the articulator using the index grooves on the base of the cast as index grooves on the base of the cast as guideguideProcessing can cause errors in occlusion Processing can cause errors in occlusion causing the incisal pin failing to contact the causing the incisal pin failing to contact the incisal tableincisal tableSelective grinding is done until the pin Selective grinding is done until the pin touches the incisal tabletouches the incisal table

11. Finishing and Polishing11. Finishing and Polishing

FinishingFinishing– Excess flash is trimmed off usingmounted wheel, Excess flash is trimmed off usingmounted wheel,

bur or arbor bandbur or arbor band– Any plaster adhering to the denture is removedAny plaster adhering to the denture is removed

PolishingPolishing– Denture are finished to a high polish making the Denture are finished to a high polish making the

denture more hygienicdenture more hygienic– Wet rag wheel and pumice slurry are usedWet rag wheel and pumice slurry are used– Final gloss is obtained with high shine materials Final gloss is obtained with high shine materials

BEFORE AFTER

DENTURE INSERTIONDENTURE INSERTION

DENTURE DELIVERYDENTURE DELIVERY

Denture DeliveryDenture Delivery

However carefully dentures are made, However carefully dentures are made, minor modifications are frequently minor modifications are frequently necessary at this stagenecessary at this stage

Denture DeliveryDenture Delivery

ProceduresProceduresCheck the dentures before insertionCheck the dentures before insertionInsert the upper dentureInsert the upper dentureInsert the lower dentureInsert the lower dentureCheck both dentures together in the mouthCheck both dentures together in the mouthGive advise to the patientGive advise to the patient

Checks before Denture InsertionChecks before Denture Insertion

1. Fitting surface1. Fitting surface- look and feel for pimples of acrylic resin - look and feel for pimples of acrylic resin - remove if necessary- remove if necessary

2. Polished surface2. Polished surface- check for roughness- check for roughness

3. Periphery3. Periphery- should be rounded except in posterior border of the - should be rounded except in posterior border of the upper dentureupper denture

4. Occlusion4. Occlusion- place dentures together by hand in maximum - place dentures together by hand in maximum intercuspationintercuspation- occlusal surfaces contact each other evenly- occlusal surfaces contact each other evenly- this may reveal large error in occlusion- this may reveal large error in occlusion

Inserting the Upper DentureInserting the Upper DentureCheck the followingCheck the following1. Retention 1. Retention

- check sulcus extension or width, check post dam- check sulcus extension or width, check post dam2. Stability 2. Stability

- check for denture mobility, apply finger pressure - check for denture mobility, apply finger pressure to the alternate sides of the archto the alternate sides of the arch3. Undercuts 3. Undercuts

- may aid in retention without pain if mucosa is - may aid in retention without pain if mucosa is thick, if thin relieve to seat the denture without painthick, if thin relieve to seat the denture without pain4. Esthetics 4. Esthetics

- appearance should be satisfactory- appearance should be satisfactory

Inserting the Lower DentureInserting the Lower Denture1. Retention1. Retention

- hardly ever possible to obtain good retention with a - hardly ever possible to obtain good retention with a complete lower denturecomplete lower denture

2. Stability2. Stability- aided by the muscle balance where the lips, cheeks and - aided by the muscle balance where the lips, cheeks and tongue do not act to displace the denture during functiontongue do not act to displace the denture during function

3. Extension3. Extension- posterior border should cover at least one-third of the - posterior border should cover at least one-third of the retromolar padretromolar pad

4. Undercuts4. Undercuts- less likely on a lower denture- less likely on a lower denture

5. Esthetics5. Esthetics- appearance should be satisfactory- appearance should be satisfactory

Both Dentures Together In the MouthBoth Dentures Together In the Mouth

1. Occlusion1. Occlusion- centric relation should coincide with centric occlusion- centric relation should coincide with centric occlusion- good balance in the lateral and protrusive excursion- good balance in the lateral and protrusive excursion- occlusion may be recorded using articulating paper - occlusion may be recorded using articulating paper - there should be even distribution of marks around the - there should be even distribution of marks around the arch, if not grind the fossae until there is even contact arch, if not grind the fossae until there is even contact

2. Vertical Dimension2. Vertical Dimension- only the Buccal Upper Lower Lingual cusps (BULL rule) - only the Buccal Upper Lower Lingual cusps (BULL rule) should be adjusted to maintain the vertical dimension should be adjusted to maintain the vertical dimension except in cases of cross-biteexcept in cases of cross-bite- though sometimes grinding the forbidden cusps is - though sometimes grinding the forbidden cusps is unavoidable (premature contact in balancing lateral unavoidable (premature contact in balancing lateral excursion)excursion)

3. Esthetics3. Esthetics- appearance should be satisfactory- appearance should be satisfactory

Patient’s InstructionsPatient’s Instructions

Eating with new dentureEating with new denture (Cut food into (Cut food into small pieces, bite on the premolar area, chew small pieces, bite on the premolar area, chew bilaterally, avoid sticky food) bilaterally, avoid sticky food) Denture careDenture care (prevent fracture, drying, & (prevent fracture, drying, & cleaning using hot water)cleaning using hot water)Maintaining tissue healthMaintaining tissue health (remove denture, (remove denture, tissue massage)tissue massage)Denture hygieneDenture hygiene (manual or chemical (manual or chemical cleaning)cleaning)Post insertion check upPost insertion check up (1 (1stst 24 hour recall, 24 hour recall, periodic check up & recall)periodic check up & recall)